Spelling suggestions: "subject:"clay"" "subject:"clae""
21 |
TWO-TOED CLAW-CLIPPERDENHAM, ROBERT DAVID 14 July 2005 (has links)
No description available.
|
22 |
The Claw Machine Tivoliautomaten / TivoliautomatenACAR, DELAL, SVENSSON, KARIN January 2020 (has links)
Claw machines have been around for about a century spreading joy and entertainment to people of all ages. They are usually seen in amusement parks and malls. In this Bachelors Thesis, one version of a claw machine will be constructed. Different constructing solutions and motors will be discussed for an easy and optimal claw machine that meet all the requirements given in the project. This report is divided into four parts, consisting of introduction, theory, construction of the machine and results. The first part is an introduction where some background information and delimitations of the project are presented. The second part of the report deals with the theory behind various selectable motors for this project as well as solutions for the design itself. The third part of the dissertation gives a detailed overview of how this particular Claw Machine was designed. Selection of materials, motors and how everything is connected and how the various parts harmonize with each other are also presented in this part. In the fourth and final part, the results are presented and a discussion of future improvements is provided. / Tivoliautomater har snart funnits i ett århundrade och har under flera årtionden varit en stor nöjesattraktion för såväl gammal som ung. De är vanligt förekommande i nöjesparker och köpcentrum. I detta kandidatexamensarbete kommer en sådan tivoliautomat att konstrueras. Diskussioner kring olika motorer och konstruktionslösningar kommer att föras, för att slutligen uppnå en konstruktion som uppfyller de givna direktiven för projektet. Denna rapport är uppdelad i fyra delar, bestående av introduktion, teori, byggandet av maskinen och resultat. Första delen är en introduktion där grundläggande fakta samt avgränsningar för projektet presenteras. Andra delen av rapporten behandlar teorin bakom olika valbara motorer för detta projekt samt lösningar för själva konstruktionen. I avhandlingens tredje del ges en detaljerad genomgång av hur just denna tivoliautomat konstruerats. Val av material, motorer samt hur allt är sammankopplat och hur de olika delarna harmoniserar med varandra presenteras även i denna del. I den fjärde och sista delen presenteras resultatet och en diskussion kring framtida förbättringar tillhandahålls.
|
23 |
Functional Morphology of Pterosaur Fingers and ClawsCollet, Josse January 2024 (has links)
Among all vertebrates, pterosaurs were the first group to evolve powered flight. This adaptation allowed them to become a diverse group, filling various habitats. Some individual pterosaurs have been interpreted as inhabiting arboreal environments, with adaptations to match. However, a broader verdict on the arboreal capabilities of pterosaurs, or lack thereof, in general remains absent. Measurements were taken of the claws of pterosaurs, and compared to measurements taken from birds and bats. The results from these comparisons show that the claw morphology of pterosaurs largely overlaps with that of modern birds. This indicates that pterosaurs encompassed a wide range of locomotive behaviours, from ground-dwelling to climbing. The results from this study show that the claw morphology of extinct taxa can be compared to data from similar extant animals to estimate their locomotive behaviour and thus possibly predict the environment they inhabited.
|
24 |
Grip, slip, petals, and pollinators : linking the biomechanics, behaviour and ecology of interactions between bees and plantsPattrick, Jonathan Gilson January 2018 (has links)
The ability to grip on petal surfaces is of crucial importance for the interactions between bees and flowers. In this thesis, I explore the biomechanics of attachment and morphological diversity of bee attachment devices, linking this to the behavioural ecology of bee interactions with flowers. Attachment devices come in two main kinds: claws or spines, and adhesive pads. Claw functioning is poorly described, particularly in terms of how their performance depends on body size, claw geometry, and surface roughness. Claw attachment performance was investigated using several insect species, each covering a large range of body masses. Weight-specific attachment forces decreased with body size, with claw sharpness seemingly playing a role. In bees there is considerable interspecific variation in tarsal claw morphology. This variation, and arolia presence/absence, was categorised for the large bee family Apidae. Cleft/bifid claws were shown to be present in the majority of the Apidae, often with differences between sexes and clades. Using Bombus terrestris, there was no evidence that cleft claws are important for pollen collection; however, I found that the inner tooth of cleft claws can act as a backup if the main tooth breaks. Although this may be one function of cleft claws, there are clearly other unresolved functions well worth further exploration. Investigations were undertaken to explore how petal surface roughness affects bee foraging behaviour. Lab-based foraging trials on B. terrestris visiting artificial flowers varying in slope, surface texture and sugar reward revealed a trade-off between the biomechanical difficulty of visiting and handling the ‘flowers’ and the quality of the reward offered. Flowers that were difficult to grip were often avoided even if they offered a higher reward. To further investigate reward preferences of bees, the effect of sucrose concentration on honey stomach offloading times was also explored. Although the majority of petals do have a rough surface, some have slippery petals. In the field, bumblebees avoided landing on slippery hollyhock petals in favour of the easy-to-grip staminal column. In contrast, honey bees, which are smaller and have larger adhesive pads, landed on both the staminal column and the petals. Slippery petals may be an adaptation to increase contact with plant reproductive structures. Grip is also important to allow the honey bee parasite Varroa destructor to climb on to their host. Attachment forces experiments found that V. destructor could support > 300 times their body mass on honey bees, giving them strong attachment even when bees attempt to remove them through grooming. A grooming-based device for treating V. destructor was tested in an apiary trial. The device was ineffective, providing valuable information for beekeepers considering using this product. In summary, this thesis improves our understanding of the biomechanics of attachment as well as identifying several important aspects of grip in bee-plant interactions.
|
25 |
Ultrassonografia Doppler do fluxo arterial digital associado à alteração do coxim digital dos bovinos / Doppler ultrasonography of digital blood flow associated with changes in bovine digital cushionGargano, Ronaldo Gomes 31 July 2015 (has links)
O objetivo do estudo foi avaliar, por meio da ultrassonografia bidimensional e da ultrassonografia Doppler, as inter-relações entre a alteração de espessura do coxim digital com os índices vasculares da artéria digital dorsal comum dos membros pélvicos dos bovinos. A avaliação ultrassonográfica Doppler é uma técnica não invasiva de avaliação de índices vasculares, assim como, indiretamente, do volume de sangue do leito vascular. Para isso, foram realizados exames ultrassonográficos da espessura do coxim digital e também avaliação ultrassonográfica Doppler da referida artéria de 13 vacas primíparas da raça Holandesa, em intervalos de 14 dias, durante 126 dias após o parto. Ao longo do experimento o coxim digital apresentou diminuição não significativa de espessura (p=0,1715) e apresentou forte correlação positiva com a média do escore de condição corporal (p=0,03, r=0,71). Ao longo do período avaliado, o fluxo de sangue aumentou significativamente (p<0,0001) e apresentou correlação negativa com os índices que denotam impedância ao deslocamento de sangue, isto é, índice de resistividade (p<0,0001, r=-0,34911) e pulsatilidade (p<0,0001, r=-0,5035). Além disso, realizou-se correlação entre a diferença diária do fluxo de sangue e a diferença da espessura do coxim digital para cada animal e constatou-se uma forte tendência à correlação entre as diferenças das variáveis (p=0,0515, r=-0,5729). Por meio dos resultados encontrados foi possível concluir que o escore de condição corporal teve forte correlação com a espessura do coxim digital, ao longo do estudo. Além disso, o fluxo de sangue, os índices referentes à velocidade de deslocamento das hemácias e o diâmetro da artéria aumentaram ao longo do trabalho. E, também, que a discreta diminuição do coxim digital não foi um fator que influenciou no aumento do fluxo de sangue e nos índices vasculares / The aim of this study was to evaluate, by bidimensional and pused Doppler ultrasound, the interrelationship between the changes of the thickness of digital cushion with vascular indices of the common dorsal digital artery of the hind limbs of cattle. Pused Doppler sonography is a non-invasive tool to assessment the vascular indices, as well as, the blood flow volume in vascular bed. So, were performed ultrasound exams of soft tissue thickness and also the Doppler ultrasonographic evaluation of that artery in thirteen first lactation Holstein cows and followed them up during 126 days in milk. Throughout the experiment the digital cushion showed a slight decrease without significance (p=0,1715), this also was strongly correlated with body condition score (p=0,03, r=0,71). The blood flow volume had significance increase (p<0,0001) and was negatively correlated with both impedance indices, resistance index (P<0,0001 r =-0,34911) and pulsatility index (p <0,0001 r =-0,5035). In addition, a correlation was performed with both daily differences of the blood flow and the thickness of the digital cushion for each animal and it was observed a strong tendency of correlation between the different variables (p=0,0515 r =-0,5729). Therefore, we can conclude that body condition score was strong correlated with the thickness of digital cushion, throughout the study. In addition, the blood flow volume, the velocity indices and the artery diameter increase throughout the days in milk. And, so, the slight decrease in the thickness of digital cushion was not a factor that influenced the increase of blood flow and vascular indices
|
26 |
Biometria dos dígitos de bovinos e bubalinos e possivel relação com enfermidades podais / Biometrics digts of cattle and buffaloes and possible relationship to foot diseasesCampos, Suyan Brethel dos Santos 21 December 2012 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2014-08-26T12:49:11Z
No. of bitstreams: 2
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
Dissertacao Suyan B dos Santos Campos.pdf: 1460159 bytes, checksum: 5641e208447c7af280dcfd31096abb45 (MD5) / Made available in DSpace on 2014-08-26T12:49:11Z (GMT). No. of bitstreams: 2
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
Dissertacao Suyan B dos Santos Campos.pdf: 1460159 bytes, checksum: 5641e208447c7af280dcfd31096abb45 (MD5)
Previous issue date: 2012-12-21 / The morphometric study of the digits of cattle and buffaloes can contribute to understanding the pathogenesis of foot diseases and may serve as a valuable tool in the selection of animals with the intention of reducing the harm caused by these bulky disease in cattle. Several breeds of cattle and buffaloes still need further studies to determine such measures. The aim of this study was to describe and compare the measurements of the digits of cattle in CurraleiroPantaneira and Nellore and Murrah buffaloes. After submission and approval by the Ethics Committee of the Universidade Federal de Goiás, Protocol No 189/11, were used 80 ends distal limb locomotion of healthy cattle and buffaloes. Members were obtained in Refrigerator under Federal Inspection, disjointed carpal-metacarpal joints and tarsal-metatarsal being used only the fore and hindlimbs rights. The morphometric measurements were obtained with the aid of a mechanical caliper graduated and angles of tweezers conferred through metal protractor. The main parameters evaluated in digital chest and pelvic limb of each animal was measured both using the digit digit as medial side were dorsal hoof angle (A), dorsal wall length (B), the bead height (H), clip height (D), the hull length (L), diagonal length of the hull (F), the digit lateral width (G), the digit width medial (M), length of the digit side (I) and medial digit length (J). For comparison of average results between races we used the Tukey test (p <0.05). Multivariate analysis for the graphical representations of canonical variables was used to express the similarity of the variables between the groups in which they used the software R. The average weight obtained at the end of the experiment each group of cattle and buffaloes was analyzed to establish a possible correlation between the measures of the digits and the size of the animals used in the experiment. The results revealed that the major buffaloes present morphometric measurements for the variables B, C, D, E, F, G, H, I and J, only the variable A (dorsal hoof angle) that have lower angles to different breeds cattle studied. We conclude that there is evidence that morphometrics influence the occurrence of illnesses digital, but does not act as an isolated factor, requiring interaction with other structural factors, and environmental management for the manifestation of these diseases. / O estudo morfométrico dos dígitos de bovinos e bubalinos pode colaborar para o entendimento da etiopatogenia das enfermidades podais, podendo servir como valiosa ferramenta na seleção de animais, com o intuito de diminuir os prejuízos vultosos ocasionados por essas doenças na bovinocultura. Várias raças de bovinos e de bubalinos ainda necessitam de estudos para a determinação de tais medidas. O objetivo com este trabalho foi descrever e comparar as medidas obtidas dos dígitos de bovinos das raças Curraleira, Pantaneira e Nelore e de bubalinos da raça Murrah. Após a submissão e aprovação pelo Comitê de Ética em Pesquisa da Universidade Federal de Goiás, protocolo No 189/ 11, foram utilizadas 80 extremidades distais dos membros locomotores de bovinos e bubalinos saudáveis. Os membros foram obtidos em Frigorífico, sob Inspeção Federal, desarticulados nas junções carpo-metacárpica e tarso- metatársica, sendo utilizados apenas os membros torácicos e pélvicos direitos. As medidas morfométricas foram obtidas com auxilio de um paquímetro mecânico graduado e os ângulos das pinças conferidos por meio de transferidor metálico. Os principais parâmetros digitais avaliados no membro torácico e pélvico de cada animal empregando-se medidas, tanto do dígito medial, quanto do dígito lateral foram: ângulo dorsal do casco (A), comprimento da parede dorsal (B), altura do talão (C), altura da pinça (D), comprimento do casco (E), comprimento diagonal do casco (F), largura do dígito lateral (G), largura do dígito medial (H), comprimento do dígito lateral (I) e comprimento do dígito medial (J). Para a comparação de médias dos resultados obtidos entre as raças foi utilizado o teste de Tukey (p<0,05). A análise multivariada para as representações gráficas das variáveis canônicas foi empregada para expressar a similaridade das variáveis estudadas entre os grupos no qual se utilizou o software R. O peso médio obtido ao final do experimento de cada grupo de bovinos e bubalinos foi analisado para estabelecer uma possível correlação entre as medidas dos dígitos e o porte dos animais empregados no experimento. Os resultados revelaram que os bubalinos apresentam as maiores medidas morfométricas para as variáveis B, C, D, E, F, G, H, I e J, apenas na variável A (ângulo dorsal do casco) têmângulos inferiores às diferentes raças de bovinos estudadas. Conclui-se que existem indícios de que a morfometria digital influencia na ocorrência de enfermidades digitais, mas não age como fator isolado, necessitando da interação com outros fatores estruturais, ambientais e de manejo para a manifestação dessas doenças.
|
27 |
Beziehungen zwischen metabolischen Störungen im peripartalen Zeitraum und subklinischer Klauenrehe beim MilchrindBystron, Sonja 19 November 2012 (has links) (PDF)
Die subklinische Klauenrehe ist eine weltweit vorkommende, multifaktorielle und bei Rindern vor allem
nach der Abkalbung gehäuft auftretende Erkrankung. Als prädisponierender Faktor für weitere, z. T. sehr
schmerzhafte Klauenerkrankungen wie Sohlengeschwüre oder White-Line-Disease besitzt sie nicht nur eine
hohe tierschutzrelevante, sondern auch eine große wirtschaftliche Bedeutung. Die Ätiologie und Pathogenese
der Klauenrehe sind bis heute nicht hinreichend geklärt. In neuerer Zeit konzentrieren sich die Forschungen
auf den peripartalen Zeitraum und den damit verbundenen metabolischen und hormonellen Einflüssen auf
das Klauengewebe. In dieser Arbeit wird der Frage nachgegangen, inwieweit eine erhöhte Fettmobilisation
bei Kühen in der negativen Energiebilanz nach der Abkalbung sowie eine verstärkte Lipolyse bei antepartal
verfetteten Kühen zur Entstehung der subklinischen Klauenrehe beitragen. Gleichzeitig soll die Frage
beantwortet werden, welche Rolle die postpartale Insulinresistenz und die dadurch verminderte
Glucoseaufnahme ins periphere Gewebe bei der Ausbildung der subklinischen Klauenrehe spielen.
Außerdem soll untersucht werden, inwiefern sich systemische Einflüsse auf die verstärkte Ausbildung der
Sohlenhämorrhagien nach der Abkalbung nachweisen lassen und ob diese anhand ausgewählter
Blutparameter vorhersehbar sind.
Für die Untersuchung wurden 30 primi- und 44 multipare Milchkühe aus drei Betrieben mit Laufstallhaltung
ausgewählt. Die Sohlenflächen aller acht Hauptklauen eines Tieres wurden nach funktionellem
Klauenschnitt 1 Woche und 8 Wochen p.p. fotografiert, in fünf Zonen eingeteilt und anhand Anzahl, Größe
und Schweregrad der sichtbaren Läsionen beurteilt. Zur weiteren Differenzierung wurden verschiedene
Klauenscores gebildet. 2 - 3 Wochen vor der Abkalbung sowie 1 Woche, 4 und 8 Wochen p.p. wurden
Blutproben entnommen und die Konzentrationen der Freien Fettsäuren (FFS), ß-Hydroxy-Butyrat (BHB),
Glucose, Insulin und Haptoglobin bestimmt. Die IGF-1-Konzentration wurde zur weiteren Einschätzung der
Energiebilanz bzw. Energieaufnahme und der Körperkondition gemessen. Die Insulinresistenz wurde anhand
basaler Insulin- und Glucose-Konzentrationen bestimmt. Des Weiteren wurde vor und nach der Abkalbungdie Rückenfettdicke sonographisch gemessen und die peripartale Fettmobilisierung über die
Rückenfettdickenänderung errechnet.
Nahezu alle untersuchten Tiere (96 %) zeigten für die subklinische Klauenrehe typische Veränderungen. Bei
über der Hälfte der Kühe waren 8 Wochen p.p. an allen vier Gliedmaßen Sohlenhämorrhagien vorhanden. Es
konnten signifikante Korrelationen der Klauenscoreparameter sowohl zwischen den einzelnen Zonen als
auch zwischen den Hinter- und Vordergliedmaßen gefunden werden. 8 Wochen p.p. war eine signifikante
Verschlechterung der Klauengesundheit im Gegensatz zur ersten Woche p.p. zu verzeichnen. Da diese
Hämorrhagien erst nach zwei Monaten an der Fußungsfläche sichtbar werden, sind die ursächlichen
Veränderungen in der Lederhaut zum Zeitpunkt der Abkalbung entstanden. Dabei waren die lateralen Klauen
der Hintergliedmaße an der Rusterholzstelle am stärksten betroffen. Ein Einfluss auf die Klauengesundheit
durch die Fütterung, die Bodenbeschaffenheit der Haltungssysteme, altersbedingt sowie durch peripartale
Erkrankungen konnte nicht gefunden werden.
Ungefähr zwei Drittel der untersuchten Kühe hatten nach der Abkalbung eine negative Energiebilanz. Sie
zeigten signifikant weniger Läsionen an den Sohlenflächen als Kühe mit positiver Energiebilanz. Eine
übermäßige Rückenfettmobilisierung führte in diesen Untersuchungen nicht zu einer Verschlechterung der
Klauengesundheit. Antepartal unterkonditionierte Tiere mit wenig Fettmobilisierung waren sogar stärker von
Klauenläsionen betroffen als normal- oder überkonditionierte Kühe. Bei Tieren mit einem peripartalen
Abfall der IGF-1-Konzentration waren signifikant mehr Veränderungen an der Sohlenfläche nachzuweisen.
Die IGF-1-Konzentration korrelierte dabei aber, im Gegensatz zu vielen Angaben in der Literatur,
hochsignifikant negativ mit der Energiebilanz und zeigte keinen Bezug zur RFD, so dass fraglich ist, ob
dieser Parameter alleine überhaupt geeignet wäre, eine Aussage über die Energiebilanz oder die Ausbildung
einer subklinischen Klauenrehe zu treffen. Bei insulinresistenten Kühen waren eine signifikante Erhöhung
der Klauenläsionen sowie ein signifikanter Abfall der IGF-1-Konzentration zu verzeichnen. Die Bestimmung
der Insulinresistenz anhand basaler Blutglucose- und Insulin-Konzentrationen bei Kühen nach der
Abkalbung erwies sich jedoch als äußerst fragwürdig. Signifikante Korrelationen zwischen den
Konzentrationen der einzelnen Blutparameter und den Klauenscoreparametern bestanden, bis auf die FFSKonzentration
2 - 3 Wochen a.p., ausschließlich 1 Woche p.p.. Allerdings blieben die Korrelationen
insgesamt relativ niedrig. Die IGF-1-Konzentration korrelierte am häufigsten sowie am engsten, Insulin und
Haptoglobin korrelierten zu keinem Zeitpunkt mit den Klauenscoreparametern.
Es kann davon ausgegangen werden, dass es sich bei den gefundenen Hämorrhagien an der Sohlenfläche um
die Ausbildung einer subklinischen Klauenrehe aufgrund systemischer Einflüsse im peripartalen Zeitraum
handelt. Eine negative Energiebilanz sowie die antepartale Verfettung der Milchkühe stellen nach den
vorliegenden Untersuchungen keinen Risikofaktor dar. In dieser Arbeit konnte nicht bestätigt werden, dass
Lipidmobilisation oder mangelnde Glucoseversorgung nach der Abkalbung eine Rolle bei der Entstehung
der subklinischen Klauenrehe spielen.
|
28 |
Soufre Atmosphérique et Changements Climatiques : une étude de modélisation pour les moyennes et hautes latitudes SudCastebrunet, Hélène 19 September 2007 (has links) (PDF)
Les moyennes et hautes latitudes Sud sont les seules régions du monde pour lesquelles le cycle naturel du soufre atmosphérique peut encore être observé sans perturbation anthropique majeure. Les aérosols soufrés sont reconnus pour leur effet radiatif et interagissent ainsi avec le climat. L'analyse des carottes de glace en Antarctique permet de connaître les variations des dépôts d'aérosols soufrés au cours des cycles glaciaire-interglaciaire, il est ainsi possible d'étudier le cycle du soufre à travers le temps. L'objectif de ce travail est de contribuer à une meilleure compréhension du cycle du soufre des régions Antarctique et sub-Antarctique, grâce à l'utilisation d'un Modèle de Circulation Générale Atmosphérique couplé à un module de chimie du soufre, le modèle LMD-ZT-Soufre (version 4). Ce travail de thèse présente tout d'abord le passage à une version récente du MCGA et une mise à jour du module de chimie. Dans un deuxième temps, le modèle a été mis en oeuvre pour simuler le climat glaciaire et le cycle du soufre au Dernier Maximum Glaciaire, il y a 20 000 ans environ. Une représentation originale de la couverture de glace de mer a été testée et son fort impact sur les émissions océaniques de sulfure de diméthyle, précurseur majoritaire des espèces soufrées aux hautes latitudes Sud, a été discuté. Les résultats du modèle suggèrent un faible impact des changements climatiques sur la production océanique de soufre pour ces régions. Ces résultats permettent d'améliorer notre connaissance des interactions soufre-climat et de dresser un bilan des incertitudes et des inconnues, tant d'un point de vue chimique que météorologique ou physique.
|
29 |
Ultrassonografia Doppler do fluxo arterial digital associado à alteração do coxim digital dos bovinos / Doppler ultrasonography of digital blood flow associated with changes in bovine digital cushionRonaldo Gomes Gargano 31 July 2015 (has links)
O objetivo do estudo foi avaliar, por meio da ultrassonografia bidimensional e da ultrassonografia Doppler, as inter-relações entre a alteração de espessura do coxim digital com os índices vasculares da artéria digital dorsal comum dos membros pélvicos dos bovinos. A avaliação ultrassonográfica Doppler é uma técnica não invasiva de avaliação de índices vasculares, assim como, indiretamente, do volume de sangue do leito vascular. Para isso, foram realizados exames ultrassonográficos da espessura do coxim digital e também avaliação ultrassonográfica Doppler da referida artéria de 13 vacas primíparas da raça Holandesa, em intervalos de 14 dias, durante 126 dias após o parto. Ao longo do experimento o coxim digital apresentou diminuição não significativa de espessura (p=0,1715) e apresentou forte correlação positiva com a média do escore de condição corporal (p=0,03, r=0,71). Ao longo do período avaliado, o fluxo de sangue aumentou significativamente (p<0,0001) e apresentou correlação negativa com os índices que denotam impedância ao deslocamento de sangue, isto é, índice de resistividade (p<0,0001, r=-0,34911) e pulsatilidade (p<0,0001, r=-0,5035). Além disso, realizou-se correlação entre a diferença diária do fluxo de sangue e a diferença da espessura do coxim digital para cada animal e constatou-se uma forte tendência à correlação entre as diferenças das variáveis (p=0,0515, r=-0,5729). Por meio dos resultados encontrados foi possível concluir que o escore de condição corporal teve forte correlação com a espessura do coxim digital, ao longo do estudo. Além disso, o fluxo de sangue, os índices referentes à velocidade de deslocamento das hemácias e o diâmetro da artéria aumentaram ao longo do trabalho. E, também, que a discreta diminuição do coxim digital não foi um fator que influenciou no aumento do fluxo de sangue e nos índices vasculares / The aim of this study was to evaluate, by bidimensional and pused Doppler ultrasound, the interrelationship between the changes of the thickness of digital cushion with vascular indices of the common dorsal digital artery of the hind limbs of cattle. Pused Doppler sonography is a non-invasive tool to assessment the vascular indices, as well as, the blood flow volume in vascular bed. So, were performed ultrasound exams of soft tissue thickness and also the Doppler ultrasonographic evaluation of that artery in thirteen first lactation Holstein cows and followed them up during 126 days in milk. Throughout the experiment the digital cushion showed a slight decrease without significance (p=0,1715), this also was strongly correlated with body condition score (p=0,03, r=0,71). The blood flow volume had significance increase (p<0,0001) and was negatively correlated with both impedance indices, resistance index (P<0,0001 r =-0,34911) and pulsatility index (p <0,0001 r =-0,5035). In addition, a correlation was performed with both daily differences of the blood flow and the thickness of the digital cushion for each animal and it was observed a strong tendency of correlation between the different variables (p=0,0515 r =-0,5729). Therefore, we can conclude that body condition score was strong correlated with the thickness of digital cushion, throughout the study. In addition, the blood flow volume, the velocity indices and the artery diameter increase throughout the days in milk. And, so, the slight decrease in the thickness of digital cushion was not a factor that influenced the increase of blood flow and vascular indices
|
30 |
Operation Eagle Claw : Hur faktorerna Enkelhet, Säkerhet och Förövning förklarar operationens misslyckandeNathanson, Sante January 2017 (has links)
On the 24th of April 1980, the US military conducted Operation Eagle Claw that aimed to free 53 American citizens held hostage by an Iranian student terror organisation in the US embassy in Teheran, Iran. This study uses the factors of simplicity, security and rehearsal to investigate why this rescue mission resulted in failure. These three factors derives from the principles of Simplicity, Security and Repetition from McRaven´s theory of relative superiority, and the criteria of Feasible Objectives, Flexibility of Mind and Tactical Competence from Gray´s theory on when special operations succeed. Based on a qualitative single case study, the results suggest that the factors of simplicity and rehearsal were absent during the planning and preparation of the operation, but that the factor of security was, however, present in excess. In the end, this dynamic generated a complex plan that was not properly rehearsed, which resulted in mission failure. The study contributes to existing research on Operation Eagle Claw, and gives further understanding to the area of special operations and its relevance to the Swedish Armed Forces.
|
Page generated in 0.0523 seconds