991 resultados para safety stock placement
Resumo:
Current methods for large-scale wind collection are unviable in urban areas. In order to investigate the feasibility of generating power from winds in these environments, we sought to optimize placements of small vertical-axis wind turbines in areas of artificially-generated winds. We explored both vehicular transportation and architecture as sources of artificial wind, using a combination of anemometer arrays, global positioning system (GPS), and weather report data. We determined that transportation-generated winds were not significant enough for turbine implementation. In addition, safety and administrative concerns restricted the implementation of said wind turbines along roadways for transportation-generated wind collection. Wind measurements from our architecture collection were applied in models that can help predict other similar areas with artificial wind, as well as the optimal placement of a wind turbine in those areas.
Resumo:
Objective To prospectively evaluate and quantify the efficacy of cadaveric fascia lata (CFL) as an allograft material in pubovaginal sling placement to treat stress urinary incontinence (SUI).
Patients and methods Thirty-one women with SUI (25 type II and six type III; mean age 63 years, range 40-75) had a CFL pubovaginal sling placed transvaginally. The operative time, blood loss, surgical complications and mean hospital stay were all documented. Before and at 4 months and 1 year after surgery each patient completed a 3-day voiding diary and validated voiding questionnaires (functional inquiry into voiding habits, Urogenital Distress Inventory and Incontinence Impact Questionnaire, including visual analogue scales).
Results The mean (range) operative time was 71 (50-120) min, blood loss 78.7 (20-250) mL and hospital stay 1.2 (1-2) days; there were no surgical complications. Over the mean follow-up of 13.5 months, complete resolution of SUI was reported by 29 (93%) patients. Overactive bladder symptoms were present in 23 (74%) patients before surgery, 21 (68%) at 4 months and two (6%) at 1 year; 80% of patients with low (<15 cmH (2) O) voiding pressures before surgery required self-catheterization afterward, as did 36% at 4 months, but only one (3%) at 1 year. Twenty-four (77%) patients needed to adopt specific postures to facilitate voiding. After surgery there was a significant reduction in daytime frequency, leakage episodes and pad use (P <0.05). The severity of leak and storage symptoms was also significantly less (P <0.002), whilst the severity of obstructive symptoms remained unchanged. Mean subjective levels of improvement were 69% at 4 months and 85% at 1 year, with corresponding objective satisfaction levels of 61% and 69%, respectively. At 1 year, approximate to 80% of the patients said they would undergo the procedure again and/or recommend it to a friend.
Conclusion Placing a pubovaginal sling of CFL allograft is a highly effective, safe surgical approach for resolving SUI, with a short operative time and rapid recovery. Storage symptoms are significantly improved, and subjective improvement and satisfaction rates are high.
Resumo:
BACKGROUND AND PURPOSE: Accurate placement of an external ventricular drain (EVD) for the treatment of hydrocephalus is of paramount importance for its functionality and in order to minimize morbidity and complications. The aim of this study was to compare two different drain insertion assistance tools with the traditional free-hand anatomical landmark method, and to measure efficacy, safety and precision. METHODS: Ten cadaver heads were prepared by opening large bone windows centered on Kocher's points on both sides. Nineteen physicians, divided in two groups (trainees and board certified neurosurgeons) performed EVD insertions. The target for the ventricular drain tip was the ipsilateral foramen of Monro. Each participant inserted the external ventricular catheter in three different ways: 1) free-hand by anatomical landmarks, 2) neuronavigation-assisted (NN), and 3) XperCT-guided (XCT). The number of ventricular hits and dangerous trajectories; time to proceed; radiation exposure of patients and physicians; distance of the catheter tip to target and size of deviations projected in the orthogonal plans were measured and compared. RESULTS: Insertion using XCT increased the probability of ventricular puncture from 69.2 to 90.2 % (p = 0.02). Non-assisted placements were significantly less precise (catheter tip to target distance 14.3 ± 7.4 mm versus 9.6 ± 7.2 mm, p = 0.0003). The insertion time to proceed increased from 3.04 ± 2.06 min. to 7.3 ± 3.6 min. (p < 0.001). The X-ray exposure for XCT was 32.23 mSv, but could be reduced to 13.9 mSv if patients were initially imaged in the hybrid-operating suite. No supplementary radiation exposure is needed for NN if patients are imaged according to a navigation protocol initially. CONCLUSION: This ex vivo study demonstrates a significantly improved accuracy and safety using either NN or XCT-assisted methods. Therefore, efforts should be undertaken to implement these new technologies into daily clinical practice. However, the accuracy versus urgency of an EVD placement has to be balanced, as the image-guided insertion technique will implicate a longer preparation time due to a specific image acquisition and trajectory planning.
Resumo:
Purpose: This study was conducted to comparatively evaluate, in a prospective and randomized manner, 2 techniques for providing double-gloving protection during arch bar placement for intermaxillary fixation. Materials and Methods: A total of 42 consecutive patients in whom application of an Erich bar was indicated for intermaxillary fixation were equally divided into 2 groups. In group 1, 2 sterile surgical gloves were used; in group 2, a nonsterile disposable inner glove was used under a sterile surgical glove. Wilcoxon, Mann-Whitney, Kruskal-Wallis, and binomial statistical tests were used to analyze the findings. Results: A total of 103 perforations were found in the outer gloves (47 in group 1 and 56 in group 2), along with 5 perforations in inner gloves in both groups (α = .01). No significant statistical difference was found between groups in terms of inner glove perforations (α = .05). The nondominant hand presented with 70.9% of the perforations, statistically significant to 1%. Conclusions: Both double-gloving techniques were found to provide effective clinician protection. The use of a nonsterile disposable glove under the surgical glove is possible for less-invasive procedures, offering the same safety as using 2 sterile surgical gloves while decreasing operational costs. This method does not eliminate the need to change gloves when a perforation is suspected or noted during the surgery, however. © 2007 American Association of Oral and Maxillofacial Surgeons.
Resumo:
Placing portal incisions during arthroscopic hip surgery presents challenges for surgeons in terms of anatomic accessibility and patient safety. Based on key anatomic landmarks and portal placement information from recent literature, suggested portal incisions were determined. Guidance in the placement of the three most common portal incision locations (anterior, anterolateral, and posterolateral) for arthroscopic surgery; in addition to visual feedback on tool trajectory to the hip joint is provided in real time by a computer aided system for hip arthroscopy. By simplifying the portal placement process, one of the most challenging aspects of arthroscopic hip surgery, an increased use of this minimally invasive technique could be possible. In addition to portal information, improvements to an existing computer aided system for arthroscopic hip surgery, including a new hip model and redesigned mechanical tracking linkage, were completed.
Resumo:
The use of drug-eluting stents (DES) in percutaneous coronary interventions (PCI) decreased the rate of restenosis and hence the need for repeat revascularization by 50-71%. DES have changed PCI. DES allow successful revascularization of anatomically challenging lesions, such as long, thin vessels, bifurcation lesions, and chronic total occlusions. A rare, but severe complication of coronary stenting is stent thrombosis, a partial or total thrombotic occlusion of the stent. The use of DES for increasingly more complex lesions, the prothrombotic effect of the antiproliferative substances, and a delayed endothelialization of DES all potentially prolong and increase the risk of stent thrombosis. Dual antiplatelet therapy for 1 year is therefore recommended after DES placement. There is currently no evidence for the efficacy and safety of routine dual antiplatelet therapy beyond 1 year. It is also recommended postponing elective surgery for 1 year and, if surgery cannot be deferred, considering continuation of acetylsalicylic acid during the perioperative period in high-risk patients with DES.
Resumo:
Stent placement has been applied in small case series as a rescue therapy in combination with different thrombolytic agents, percutaneous balloon angioplasty (PTA), and mechanical thromboembolectomy (MT) in acute stroke treatment. These studies report a considerable mortality and a high rate of intracranial hemorrhages when balloon-mounted stents were used. This study was performed to evaluate feasibility, efficacy, and safety of intracranial artery recanalization for acute ischemic stroke using a self-expandable stent.
Resumo:
BACKGROUND: Whole-body hypothermia reduced the frequency of death or moderate/severe disabilities in neonates with hypoxic-ischemic encephalopathy in a randomized, controlled multicenter trial. OBJECTIVE: Our goal was to evaluate outcomes of safety and effectiveness of hypothermia in infants up to 18 to 22 months of age. DESIGN/METHODS: A priori outcomes were evaluated between hypothermia (n = 102) and control (n = 106) groups. RESULTS: Encephalopathy attributable to causes other than hypoxia-ischemia at birth was not noted. Inotropic support (hypothermia, 59% of infants; control, 56% of infants) was similar during the 72-hour study intervention period in both groups. Need for blood transfusions (hypothermia, 24%; control, 24%), platelet transfusions (hypothermia, 20%; control, 12%), and volume expanders (hypothermia, 54%; control, 49%) was similar in the 2 groups. Among infants with persistent pulmonary hypertension (hypothermia, 25%; control, 22%), nitric-oxide use (hypothermia, 68%; control, 57%) and placement on extracorporeal membrane oxygenation (hypothermia, 4%; control, 9%) was similar between the 2 groups. Non-central nervous system organ dysfunctions occurred with similar frequency in the hypothermia (74%) and control (73%) groups. Rehospitalization occurred among 27% of the infants in the hypothermia group and 42% of infants in the control group. At 18 months, the hypothermia group had 24 deaths, 19 severe disabilities, and 2 moderate disabilities, whereas the control group had 38 deaths, 25 severe disabilities, and 1 moderate disability. Growth parameters were similar between survivors. No adverse outcomes were noted among infants receiving hypothermia with transient reduction of temperature below a target of 33.5 degrees C at initiation of cooling. There was a trend in reduction of frequency of all outcomes in the hypothermia group compared with the control group in both moderate and severe encephalopathy categories. CONCLUSIONS: Although not powered to test these secondary outcomes, whole-body hypothermia in infants with encephalopathy was safe and was associated with a consistent trend for decreasing frequency of each of the components of disability.
Resumo:
El sector ferroviario ha experimentado en los últimos años un empuje espectacular acaparando las mayores inversiones en construcción de nuevas líneas de alta velocidad. Junto a esta inversión inicial no se debe perder de vista el coste de mantenimiento y gestión de las mismas y para ello es necesario avanzar en el conocimiento de los fenómenos de interacción de la vía y el material móvil. En los nuevos trazados ferroviarios, que hacen del ferrocarril un modo de transporte competitivo, se produce un notable aumento en la velocidad directamente relacionado con la disminución de los tiempos de viaje, provocando por ello elevados esfuerzos dinámicos, lo que exige una elevada calidad de vía para evitar el rápido deterioro de la infraestructura. Resulta primordial controlar y minimizar los costes de mantenimiento que vienen generados por las operaciones de conservación de los parámetros de calidad y seguridad de la vía férrea. Para reducir las cargas dinámicas que actúan sobre la vía deteriorando el estado de la misma, debido a este aumento progresivo de las velocidades, es necesario reducir la rigidez vertical de la vía, pero igualmente este aumento de velocidades hace necesarias elevadas resistecias del emparrillado de vía y mejoras en las plataformas, por lo que es necesario buscar este punto de equilibrio en la elasticidad de la vía y sus componentes. Se analizan las aceleraciones verticales medidas en caja de grasa, identificando la rigidez vertical de la vía a partir de las frecuencias de vibración vertical de las masas no suspendidas, correlacionándola con la infraestructura. Estas aceleraciones verticales se desprenden de dos campañas de medidas llevadas a cabo en la zona de estudio. En estas campañas se colocaron varios acelerómetros en caja de grasa obteniendo un registro de aceleraciones verticales a partir de las cuales se ha obteniendo la variación de la rigidez de vía de unas zonas a otras. Se analiza la rigidez de la vía correlacionándola con las distintas tipologías de vía y viendo la variación del valor de la rigidez a lo largo del trazado ferroviario. Estos cambios se manifiestan cuando se producen cambios en la infraestructura, de obras de tierra a obras de fábrica, ya sean viaductos o túneles. El objeto principal de este trabajo es profundizar en estos cambios de rigidez vertical que se producen, analizando su origen y las causas que los provocan, modelizando el comportamiento de los mismos, para desarrollar metodologías de análisis en cuanto al diseño de la infraestructura. Igualmente se analizan los elementos integrantes de la misma, ahondando en las características intrínsecas de la rigidez vertical global y la rigidez de cada uno de los elementos constituyentes de la sección tipo ferroviaria, en cada una de las secciones características del tramo en estudio. Se determina en este trabajo si se produce y en qué medida, variación longitudinal de la rigidez de vía en el tramo estudiado, en cada una de las secciones características de obra de tierra y obra de fábrica seleccionadas analizando las tendencias de estos cambios y su homogeneidad a lo largo del trazado. Se establece así una nueva metodología para la determinación de la rigidez vertical de la vía a partir de las mediciones de aceleraciones verticales en caja de grasa así como el desarrollo de una aplicación en el entorno de Labview para el análisis de los registros obtenidos. During the last years the railway sector has experienced a spectacular growth, focusing investments in the construction of new high-speed lines. Apart from the first investment the cost of maintaining and managing them has to be considered and this requires more knowledge of the process of interaction between track and rolling stock vehicles. In the new high-speed lines, that make of the railway a competitive mode of transport, there is a significant increase in speed directly related to the shorten in travel time, and that produces high dynamic forces. So, this requires a high quality of the track to avoid quickly deterioration of infrastructure. It is essential to control and minimize maintenance costs generated by maintenance operations to keep the quality and safety parameters of the railway track. Due to this gradual increase of speed, and to reduce the dynamic loads acting on the railway track causing its deterioration, it is necessary to reduce the vertical stiffness of the track, but on the other hand this speed increase requires high resistance of the railway track and improvements of the railway platform, so we must find the balance between the elasticity of the track and its components. Vertical accelerations in axle box are measured and analyzed, identifying the vertical stiffness of the railway track obtained from the vertical vibration frequency of the unsprung masses, correlating with the infrastructure. These vertical accelerations are the result of two measurement campaigns carried out in the study area with the placement of several accelerometers located in the axle box. From these vertical accelerations the variation of the vertical stiffness from one area to another is obtained. The track stiffness is analysed relating with the different types of infrastructure and the change in the value of the stiffness along the railway line. These changes are revealed when changes in infrastructure occurs, for instance; earthworks to bridges or tunnels. The main purpose of this paper is to examine these vertical stiffness changes, analysing its origins and causes, modelling their behaviour, developing analytical methodologies for the design of infrastructure. In this thesis it is also reviewed the different elements of the superstructure, paying special attention to the vertical stiffness of each one. In this study is determined, if it happens and to what extent, the longitudinal variation in the stiffness of track along the railway line studied in every selected section; earthwork, bridges and tunnels. They are also analyzed trends of these changes and homogeneity along the path. This establishes a new method for determining the vertical stiffness of the railway track from the vertical accelerations measured on axle box as well as an application developed in LabView to analyze the recordings obtained.
Resumo:
t. 1. L'explication des lois et règlements relatifs aux valeurs mobilières ...--t. 2. Des études sur les principales valeurs négociées à la Bourse de Paris ...
Resumo:
National Highway Traffic Safety Administration, Washington, D.C.
Resumo:
This paper investigates the effectiveness of virtual product placement as a marketing tool by examining the relationship between brand recall and recognition and virtual product placement. It also aims to address a gap in the existing academic literature by focusing on the impact of product placement on recall and recognition of new brands. The growing importance of product placement is discussed and a review of previous research on product placement and virtual product placement is provided. The research methodology used to study the recall and recognition effects of virtual product placement are described and key findings presented. Finally, implications are discussed and recommendations for future research provided.