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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.
1

Effects of Supplementing Ponies with Dietary Fat on Nutrient Digestibility and Blood Insulin, Glucose, and Fatty Acid Concentrations

Bova, Toree Lee 14 August 2015 (has links)
Fat supplementation is a common practice to increase caloric intake in the performance horse. The effects of fat on fiber digestibility is unknown. Understanding of digestibility in the equine digestive tract is limited by sampling technique. While cecal and ileal cannulations have previously been utilized to determine equine nutrient digestibility and gastrointestinal physiology, the current research has been limited to singular portions of the equine digestive tract. The objectives of this dissertation were to determine the effects of dietary fat supplementation on nutrient digestibility and blood insulin, glucose, and fatty acid concentrations using dual cannulated ponies. The first step to this objective was establishment of a dual cannulated pony herd for research. This study resulted in a post-operation survival rate of 63%. Five of the dual cannulated ponies were fed hay and pelleted alfalfa and supplemented with vegetable oil at 0, 5, 10, or 15 % of total diet. Ileal, cecal, fecal, and blood samples were taken with blood samples analyzed for glucose, insulin and fatty acids. There was a treatment by time effect (P < 0.1) for apparent ileal and cecal fat digestibility and apparent cecal digestibility of crude protein. Apparent total tract digestibility of NDF, ADF and fat was affected by time (P < 0.1). Adding fat increased (P < 0.1) apparent total tract digestibility of fat. At 0 h post feeding apparent total tract digestibility of protein was greatest (P < 0.1) compared to other time periods. Plasma concentration of insulin increased (P < 0.1) over time. Ponies consuming 0 % fat diet had increased C14:0 compared to 5, 10, and 15 % diet. Adding fat at 5, 10, and 15 % of the diet increased C18:2 n-6 when the ponies were fed 0 % fat. Further research using a dual cannulated equine research herd is needed to more completely understand digestibility of other components of the equine diet.
2

The Use of Steered Ileo-cecal Valve Cannulated Pigs to Evaluate the Effects of Adding Phytase or Beta-mannanase to the Diet on Amino Acid, Mineral and Energy Utilization

Radcliffe, John Scott 27 April 2000 (has links)
Forty-six barrows fitted with steered ileo-cecal valve cannulas were used in four experiments to evaluate the effects of supplementing swine diets with microbial phytase or beta-mannanase on the apparent ileal (AID) and/or apparent total tract digestibility (ATTD) of amino acids, N, Ca, P, DM and energy. In Exp. 1, the addition of phytase to low CP corn-soybean meal based diets increased the AID of Ca (P < .01), P (P < .001), and all amino acids (P < .10) measured except Leu, Ser, Pro, Met, His and Tyr. In Exp. 2, the addition of microbial phytase to corn-soybean meal, corn-soybean meal-wheat middlings, or corn-soybean meal-meat and bone meal based diets resulted in increased AID of Ca and P, but had no effect (P > .1) on amino acid digestibilities. Diet type affected all digestibility measurements, but did not affect the efficacy of supplemental phytase. In Exp. 3, the addition of microbial phytase to corn-wheat-soybean meal, corn-wheat-cannola, or sorghum-corn-soybean meal based diets led to an increased ( P <.05) AID of P, Asp, Thr, Ser, Ala, Tyr, Phe, Lys and Arg. In Exp. 4, the addition of beta-mannanase to corn-soybean meal based swine diets led to an increased AID of DM and ATTD of energy. In addition, the AID of all amino acids measured were increased numerically, with many of these values approaching significance. The results of these studies demonstrate that supplementing pig diets with phytase or beta-mannanase, results in an increased digestibility of certain dietary components due to the breakdown of anti-nutritive compounds in the diet. / Ph. D.
3

Experimental Investigations of Airflow in the Human Upper Airways During Natural and Assisted Breathing

Spence, Callum James Thomas January 2011 (has links)
Nasal high flow (NHF) cannulae are used to deliver heated and humidified air to patients at steady flows ranging from 5-50 l/min. Knowledge of the airflow characteristics within the nasal cavity with NHF and during natural breathing is essential to understand the treatment's efficacy. In this thesis, the distribution and velocity of the airflow in the human nasal cavity have been mapped during natural and NHF assisted breathing with planar- and stereo-PIV in both steady and oscillatory flow conditions. Anatomically accurate transparent silicone models of the human nasal cavity were constructed using CT scan data and rapid prototyping. Breathing flowrates and waveforms were measured in vivo and dimensionally scaled by Reynolds and Womersley number matching to reproduce physiological conditions in vitro. Velocities of 2.8 and 3.8 m/s occurred in the nasal valve during natural breathing at peak expiration and inspiration, respectively; however on expiration the maximum velocity of 4.2 m/s occurred in the nasopharynx. Velocity magnitudes differed appreciably between the left and right sides of the nasal cavity, which were asymmetric. NHF modifies nasal cavity flow patterns significantly, altering the proportion of inspiration and expiration through each passageway and producing jets with in vivo velocities up to 20.8 m/s for 40 l/min cannula flow. The main flow stream passed through the middle airway and along the septal wall during both natural inspiration and expiration, whereas NHF inspired and expired flows remained high through the nasal cavity. Strong recirculating features are created above and below the cannula jet. Results are presented that suggest the quasi-steady flow assumption is invalid in the nasal cavity during both natural and NHF assisted breathing. The importance of using a three-component measurement technique when investigating nasal flows has been highlighted. Cannula flow has been found to continuously flush the nasopharyngeal dead space, which may enhance carbon dioxide removal and increase oxygen fraction. Close agreement was found between numerical and experimental results performed in identical conditions and geometries.
4

Does Increasing Flow to a High Flow Nasal Cannula Affect Mean Airway Pressure in an In Vitro Model?

Murray, Robert Brent 10 December 2009 (has links)
DOES INCREASING FLOW TO A HIGH FLOW NASAL CANNULA AFFECT MEAN AIRWAY PRESSURE IN AN IN VITRO MODEL? Introduction: High-flow nasal cannulas (HFNC) have become popular with many institutions for administration of oxygen (O2). HFNCs are also being used in pediatric and neonatal populations for administration of continuous positive airway pressure (CPAP) as a treatment for respiratory distress. Adult patients are being treated with HFNCs in a effort to provide a high percentage of O2 and correct hypoxemia and other related conditions. The purpose of this study was to examine the effect of increasing flow via a HFNC to an in vitro model to examine the effect of flow on mean airway pressure (MPAW). Method: An in vitro model to simulate non-labored and labored spontaneous breathing was developed using a Michigan Instrument Laboratory Test and Training Lung (MIL TTL) driven by a Hamilton Galileo ventilator to produce a negatively based, inspired tidal volume. Flow was introduced to the MIL TTL via a 41 French double lumen endotracheal tube. Airway pressure measurements were observed via a pressure monitoring port placed between the MIL TTL and the endotracheal tube and connected to the auxiliary pressure monitoring port located on the front of the Galileo ventilator. A Vapotherm 2000i with adult transfer chamber and adult cannula, a Fisher Paykel Optiflow, and a generic HFNC consisting of a concha column and a Salter labs high-flow cannula were tested at 20, 30, and 40LPM flowrates. Data was recorded using two respiratory rates (12 and 24) and two peak flowrates (35 and 65LPM) to simulate non-labored and labored breathing. All other parameters were unchanged and the I:E ratio was consistent. Data Analysis: SPSS 16.0 for Windows was used to analyze all data for this study. Descriptive statistics, one-way analysis of variance (ANOVA), and post hoc Bonferroni was used for this study. A p value less than 0.05 were considered significant. Results: Average MPAW for all devices were increased at all three flowrates. MPAW was highest at 40LPM flow producing 3.1cmH2O averaged for all HFNCs and both respiratory patterns. The difference in MPAW produced by the three HFNCs were also significant with at p=0.000 at all flow rates. Post hoc Bonferroni adjusted probabilities further showed all device comparisons significant except for Vapotherm-Vapotherm Labored at 30 and 40 LPM flow rates and Vapotherm-Generic Labored at 20 LPM at p<0.05. These three comparisons were at p>0.05 and were statistically equal. The generic HFNC produced the highest MPAW (3.5cmH2O). Conclusion: Increased flow via a HFNC does increase MPAW. The Vapotherm, Optiflow, and generic HFNC did not produce the same level of MPAW in this study.
5

In Vitro Evaluation oF Aerosol Drug Delivery With And Without High Flow Nasal Cannula Using Pressurized Metered Dose Inhaler And Jet Nebulizer in Pediatrics

Alalwan, Mahmood A 31 July 2012 (has links)
Background: HFNC system is a novel device used with aerosol therapy and seems to be rapidly accepted. Although there are some studies conducted on HFNC and vibrating mesh nebulizer, the effect of HFNC on aerosol delivery using jet nebulizer or pressurized metered-dose inhaler (pMDI) has not been reported. In an effort to examine the effect of HFNC on aerosol deposition, this study was conducted to quantify aerosol drug delivery with or without a HFNC using either pMDI or jet nebulizer. Methodology: The SAINT model, attached to an absolute filter (Respirgard II, Vital Signs Colorado Inc., Englewood, CO, USA) for aerosol collection, was connected to a pediatric breathing simulator (Harvard Apparatus, Model 613, South Natick, MA, USA). To keep the filter and the SAINT model in upright position to collect aerosolized drug, an elbow adapter was connected between the absolute filter and the breathing simulator. An infant HFNC (Optiflow, Fisher & Paykel Healthcare LTD., Auckland, New Zealand) ran at 3 l/min O2 was attached to the nares of the SAINT model. Breathing parameters used in this study were Vt of 100 mL, RR of 30 breaths/min, and I:E ratio of 1: 1.4. Aerosol drug was administered using: 1) Misty-neb jet nebulizer (Allegiance Healthcare, McGaw Park, Illinois, USA) powered by air at 8 l/min using pediatric aerosol facemask (B&F Medical, Allied Healthcare Products, Saint Louis, MO, USA) to deliver albuterol sulfate (2.5 mg/3 mL NS), and 2) Four actuations of Ventolin HFA pMDI (90 μg/puff) (GlaxoSmithKline, Research Triangle Park, NC, USA) combined with VHC (AeroChamber plus with Flow-Vu, Monaghan Medical, Plattsburgh, NY, USA). Aerosol was administered to the model with and without the HFNC and another without (n=3). Drug was collected on an absolute filter, eluted and measured using spectrophotometry. Independent t tests were performed for data analysis. Statistical significance was determined with a p value of <0.05. Results: The mean inhaled mass percent was greatest for pMDI with (p = 0.0001) or without HFNC (p = 0.003). Removing HFNC from the nares before aerosol treatment trended to increase drug delivery with the jet nebulizer (p = 0.024), and increased drug delivery by 6 fold with pMDI (p = 0.003). Conclusions: Aerosol drug may be administered in pediatrics receiving HFNC therapy using either jet nebulizer or pMDI. However, using pMDI, either with or without HFNC, is the best option. When delivering medical aerosol by mask, whether by jet nebulizer or pMDI, removing HFNC led to an increase in inhaled mass percent. However, the benefit of increased aerosol delivery must be weighed against the risk of lung derecruitment when nasal prongs are removed.
6

Estudo sobre agulhas hipodérmicas: variação do esforço de penetração em um tecido artificial / Study on hypodermic needles: variation of the penetration effort in an artificial tissue

Cavassana, Sidnei [UNESP] 01 August 2017 (has links)
Submitted by SIDNEI CAVASSANA null (sidnei5333@gmail.com) on 2017-09-16T17:06:01Z No. of bitstreams: 1 Mestrado Sidnei versão Final.pdf: 4006618 bytes, checksum: 3e1f03fc6f46516ae312a5bc3c98f9bb (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-19T18:25:30Z (GMT) No. of bitstreams: 1 cavassana_s_me_ilha.pdf: 4006618 bytes, checksum: 3e1f03fc6f46516ae312a5bc3c98f9bb (MD5) / Made available in DSpace on 2017-09-19T18:25:30Z (GMT). No. of bitstreams: 1 cavassana_s_me_ilha.pdf: 4006618 bytes, checksum: 3e1f03fc6f46516ae312a5bc3c98f9bb (MD5) Previous issue date: 2017-08-01 / O medo da dor relacionada à injeção é um empecilho à terapia de injetáveis. As injeções hipodérmicas são motivos de grande ansiedade e de reduzida adesão à aplicação subcutânea de insulina para o controle glicêmico em diabéticos ou no tratamento da esclerose múltipla, aumentando o risco de complicações e mortalidade. Neste trabalho foi analisado como algumas das características da agulha podem influenciar a sensação de dor na injeção. Mediu-se o esforço de penetração de agulhas em um tecido artificial (modelo substituto da pele), para diferentes diâmetros de cânula, rugosidade, profundidade de penetração, lubrificação e ângulos do bisel da ponta perfurante. Este estudo visou encontrar alternativas para facilitar a aplicação e a autoaplicação de injeções hipodérmicas, aumentando a segurança e conforto, diminuindo a intensidade da dor percebida pelo paciente. Para isso, analisou-se no projetor de perfil e no MEV o bisel de agulhas usadas repetidas vezes para verificar a perda do perfil ou a formação de rebarbas que possam dificultar a penetração ou traumatizar o tecido durante o reuso de agulhas. Também foi analisado sob o ponto de vista mecânico, o que pode ser feito para prevenir que as agulhas usadas na aplicação subcutânea não atinjam inadvertidamente o músculo. O maior esforço de penetração observado nas agulhas com maior ângulo do bisel é responsável pela percepção de dor do paciente. / Fear of injection-related pain is a drawback to injectable therapy. Hypodermic injections are a cause for great anxiety and reduced adherence to the subcutaneous application of insulin for glycemic control in diabetics or in the treatment of multiple sclerosis, increasing the risk of complications and mortality. In this work, it was analyzed how some of the characteristics of the needle can influence the sensation of pain in the injection. The needle penetration effort was measured in an artificial tissue (substitute skin model) for different cannula diameters, roughness, depth of penetration, lubrication and angles of the perforating tip bevel. This study aimed to find alternatives to facilitate the application and self-application of hypodermic injections, increasing safety and comfort, reducing the pain intensity perceived by the patient. To do this, the bevel of needles used repeatedly was analyzed in the profile projector and SEM to verify the loss of the profile or the formation of burrs that could hamper the penetration or traumatize the tissue during the reuse of needles. It has also been mechanically analyzed, which can be done to prevent that the needles used in the subcutaneous application do not inadvertently reach the muscle. The greater penetration effort observed in the needles with greater angle of the bevel is responsible for the patient's perception of pain.
7

OPTIMIZING NASAL CANNULAS FOR INFANTS USING COMPUTATIONAL FLUID DYNAMICS

El-Achwah, Ahmad, Mr. 01 January 2019 (has links)
Aerosolized medications can potentially be delivered to the lungs of infants through a nasal cannula interface. However, nose-to-lung delivery technologies currently allow for ~1% of the loaded dose to reach an infant’s lungs. Conventional dry powder inhalers (DPI) are superior to other types of inhalers in many ways. However, passive DPIs that operate based on user inhalation and require large volumes of airflow are not applicable to infants. To overcome this challenge, positive pressure DPIs have been developed that enable aerosol delivery to infants. Unless an adequate nasal interface is used with these devices, a significant amount of drug will still be lost. Computational fluid dynamics (CFD) provide a method to assess the performance of a nasal cannula interface and optimize its performance. In this study, a CFD model was first experimentally validated using the low-Reynolds number k-ω turbulence model, then used to assess and optimize several conical diffuser cannula designs for infants. The performance of a cannula depends primarily on two requirements: the amount deposited particles and the cannula’s volume. It was found that 90 and 100 mm long simple diffusers achieved the necessary deposition and volume requirements when operated at 3 and 5 liters per minute, respectively. Additionally, including clean sheath co-flow air with the 70 mm long diffuser achieved the targeted performance requirements. Inclusion of recent advancements in the field with the recommended cannula designs is likely to improve pharmaceutical aerosol delivery to infants using the nose-to-lung approach.
8

Srovnání ošetřování cévních vstupů na JIP a standardním oddělení / Comparison of the Vascular Access Care in the Intensive Care Unit and Standart Departement

Vašková, Marcela January 2012 (has links)
Abstaract(thesis) In my thesis, I decided to take the issue of treatment of vascular input in surgical department and surgical intensive care units. This nursing problem can be found practically on every inpatient department and each nurse meets with vascular access dutiny her career. The work is divided into theoretical part and empirical part. The first theoretical part deals with the history of vascular input, a list of basic vascular entries and the educational process. Of the vascular inputs, the work focuses especially on central venous catheter and peripheral venous catheter. The second empirical part focuses on the evaluation of collected data and their statistical analysis. Before the research 4 hypotheses were provided. These hypothesis were confirmed by statistical evaluation of questionnaires. The questionnaires were filled in by sisters from the surgical department and intensive care units. At the end of the thesis is work evaluation. Keywords Vascular access, peripheral venous cannula, central venous cannula, nursing, dressing, asepsis, infections, nurse, patient
9

Acute and Chronic Effects of Artificial Rearing on Rat Genioglossus Muscle

Moore, Wayne Allen, Jr. 01 January 2005 (has links)
In most mammals, nutritive suckling is critical during the early neonatal period. The genioglossus (GG) muscle in rat plays an important role in protruding the tongue for efficient suckling. The purpose of this study was to examine the contractile properties and myosin heavy chain (MHC) phenotype of the GG following an early period of artificial rearing, which reduced nutritive suckling. Beginning at three days of age Sprague-Dawley rats were fed via implanted gastric cannula until postnatal day 14 (P14). At P14, artificially reared (AR) rat pups were either placed with a lactating dam until the end of the weaning period and allowed to mature until postnatal day 42 (P42), or anesthetized and prepared for physiological experimentation. GG contractile properties at P14 and P42 in AR and dam reared (DR) rats were obtained with a force transducer and digital recording system through stimulation of the medial branch of the hypoglossal nerve. Following physiological experimentation, muscle samples were removed and stored for MHC analysis. Comparisons were made between AR and DR groups at P14 and P42. At P14 maximum tetanic tension and fatigue index were lower in the AR group than the DR group and no differences were found in MHC distribution. By day 42, AR rats had a higher fatigue index that DR rats and DR rats had a higher percentage of MHCIIa than AR rats. The artificial rearing technique employed in this study was adequate to produce chronic changes in fatigue resistance and MHC distribution in GG muscle. GG muscle of premature human infants requiring early artificial feedings may develop similar changes in their contractile characteristics and MHC phenotype.
10

Modelo de cânula vaginal na endoscopia transluminal por orifícios naturais (NOTES) pelo acesso transvaginal com extração ovariana (NOSE) em éguas hígidas / Cannula in natural orifice transluminal endoscopic surgery (NOTES) and using transvaginal access for ovary extration (NOSE) in healthy mares

Merini, Luciana Paula January 2017 (has links)
A técnica cirúrgica endoscópica transluminal por orifícios naturais (NOTES) tem por definição envolver a introdução de um endoscópio no interior da cavidade abdominal através de uma perfuração intencional de uma víscera (p.ex. estômago, reto, vagina) e realizar uma exploração e/ou operação intra-abdominal. A incisão cirúrgica realizada pela técnica de NOTES tem a vantagem de ser utilizada para a retirada da cavidade abdominal de espécimes (NOSE) reseccionadas através de uma laparoscopia padrão ou por NOTES. O presente estudo teve por objetivo verificar a viabilidade da cânula vaginal em realizar o acesso transvaginal para a cavidade abdominal através da técnica de NOTES transvaginal em éguas hígidas posicionadas em estação e avaliar o acesso vaginal como canal de extração de espécimes (NOSE) em éguas submetidas à ovariectomia laparoscópica via flanco. Foram utilizadas 6 éguas hígidas para ambos os procedimentos cirúrgicos. Os animais foram submetidos a jejum alimentar pré-cirúrgico de 24 à 30 horas. Para a sedação utilizou-se cloridrato de detomidina e cloridrato de lidocaína para execução da epidural baixa. A incisão vaginal foi realizada dorsal à cérvix na posição horária de 12 horas utilizando uma cânula vaginal de ponta romba rosqueada e realizada sob visualização indireta através do endoscópio flexível inserido dentro da cânula. A remoção dos ovários via vaginal ocorreu em quatro das seis éguas utilizadas no experimento. Das quatro éguas, três tiveram a necessidade do aumento manual da colpotomia para apreensão manual dos ovários intracavitária e sua remoção. Em dois animais os ovários tiveram de ser seccionados e removidos através do flanco pelo aumento da incisão do canal de trabalho laparoscópico. A execução cirúrgica do acesso à cavidade abdominal via transvaginal e a técnica de extração de espécimes por NOSE submetidas à ovariectomia laparoscópica via flanco é possível de ser realizada em éguas hígidas. / The technique of Natural Orifice Transluminal Endoscopic Surgery (NOTES), by definition, concerns the introduction of an endoscope in the abdominal cavity through an intentional perforation of a viscera (for ex., stomach, recto, vagina) and performs an intra-abdominal exploration and/or operation. The surgical incision performed through the NOTES technique has the benefit of being used to remove resected specimens (NOSE) from the abdominal cavity through a standard laparoscopy or through NOTES. The present study had the purpose to check the practicality of the vaginal cannula in performing transvaginal access to the abdominal cavity through the NOTES technique in standing healthy mares and assess the vaginal access as an canal extraction of specimens (NOSE) in mares subjected to laparoscopic ovariectomy. Six healthy mares were used for both surgical procedures. The food was withheld between 24 to 30 hours before surgery. They were sedated with detomidine hydrochloride and to perform the low epidural, lidocaine hydrochloride was used. The vaginal incision was performed dorsally to the cervix at 12 o’clock position using threaded round tip vaginal cannula and performed under indirect viewing through a flexible endoscope inserted in the cannula. The ovaries were removed through the vagina in four of the six mares used in the experiment. From the four mares, three were required to manually increase the colpotomy for manual intracavitary seizure of the ovaries and their removal. In two of the animals, the ovaries had to be cut and removed through the flank, increasing the incision of the laparoscopic working channel. The procedure to create the access to the abdominal cavity through the vagina to perform the NOTES technique and the specimen extraction technique through NOSE subjected to laparoscopic ovariectomy in healthy mares did not demonstrate high difficulties in its execution nor post-surgical complications, confirming the practicality of the two techniques in the equine species.

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