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81.
Fotis Liarokapis Louis Macan Gary Malone Genaro Rebolledo-Mendez Sara de Freitas 《The Visual computer》2009,25(12):1109-1120
This paper presents tangible augmented reality gaming environment that can be used to enhance entertainment using a multimodal
tracking interface. Players can interact using different combinations between a pinch glove, a Wiimote, a six-degrees-of-freedom
tracker, through tangible ways as well as through I/O controls. Two tabletop augmented reality games have been designed and
implemented including a racing game and a pile game. The goal of the augmented reality racing game is to start the car and
move around the track without colliding with either the wall or the objects that exist in the gaming arena. Initial evaluation
results showed that multimodal-based interaction games can be beneficial in gaming. Based on these results, an augmented reality
pile game was implemented with goal of completing a circuit of pipes (from a starting point to an end point on a grid). Initial
evaluation showed that tangible interaction is preferred to keyboard interaction and that tangible games are much more enjoyable. 相似文献
82.
Analysis of factors contributing to success in a program of micromanipulation-assisted fertilization
GJ Garrisi AJ Chin PM Dolan HM Nagler M Vasquez-Levin D Navot JW Gordon 《Canadian Metallurgical Quarterly》1993,59(2):366-374
OBJECTIVE: To determine factors important to clinical success in micromanipulation-assisted in vitro fertilization (IVF). DESIGN: Procedures invoked in two separate series of micromanipulation-assisted IVF cycles, one unsuccessful (series I) and the other successful (series II), were compared in an effort to identify changes that led to clinical success. SETTING: University-based IVF clinic. PATIENTS: In both IVF series involving micromanipulation, patients consisted of infertile couples who fit any of five categories of male-factor related infertility. The female patients underwent controlled hyperstimulation for oocyte retrieval and the oocytes were inseminated normally or were subjected either to partial zona dissection or subzonal sperm insertion to assist fertilization. Results in all groups were compared between the two patient series. RESULTS: In the successful series II, a noticeable improvement in fertilization rate and embryo quality was observed compared with series I. A significant increase in the percentage of patients reaching embryo transfer, the pregnancy rate per transfer, and the pregnancy rate per retrieval were noted in series II; a 25% ongoing pregnancy rate per retrieval was observed overall in this successful group, with "ongoing" defined as manifestation of at least a fetal sac on ultrasound with no detectable problems. Patients with a mixed transfer of embryos derived from manipulated and normally inseminated oocytes had a 75% rate of pregnancy per transfer in series II. Differences between the two series could not be attributed to patient selection or biases in selection of oocytes relegated to micromanipulation. However, oocyte handling, micromanipulation, and culture protocols differed significantly between the two series in that temperature and pH of oocytes was better controlled, and micromanipulation time was minimized in series II. CONCLUSION: Success in micromanipulation depends on maintenance of the oocyte in a stable and supportive environment throughout the micromanipulation procedure. It is also important to minimize trauma to the eggs by performing micromanipulation rapidly and with minimal distortion of the egg. Patients with a poor fertilization rate in standard IVF may experience a substantial increase in the likelihood of pregnancy when micromanipulation-assisted fertilization is performed on some eggs. 相似文献
83.
JC Langenbrunner PM Wortman WH Yeaton JJ Holloway 《Canadian Metallurgical Quarterly》1993,9(2):286-303
Carotid endarterectomy (CE) surgery for asymptomatic patients remains controversial despite hundreds of published studies and recent randomized trials. Safety and efficacy are assessed using a quantitative synthesis method derived from meta-analysis and a "critical multiplist" inference approach. In addition, multivariate analyses reveal that use of a surgical shunt could further improve CE outcomes. Methods are examined for both their "confirmatory" and "exploratory" value. 相似文献
84.
H Kopsa J Zazgornik P Schmidt H Pall SJ Pok PM Bayer P Balcke P Pils 《Canadian Metallurgical Quarterly》1977,107(27):942-947
Two cases with acute renal failure after prolonged hypothermia are presented. Both patients were found in come, became rapidly uremic and required hemodilaysis treatment. Although the laboratory findings were typical of severe muscle damage, e.g. elevated levels of serum creatinine phosphokinase, serum lactic dehydrogenase and serum aldolase activities, visible "crush-injuries" were not found. Acute renal failure was characterized by extreme catabolism and severe metabolic acidosis. After 4 and 10 hemodialyses respectively, the patients became polyuric and finally were discharges with normal renal and muscle function. Hypotension with diminished renal perfusion and nontraumatic rhabdomyolysis due to prolonged hypothermia are regarded as the dominant pathogenetic factors in the acute renal failure. 相似文献
85.
The present review has attempted to summarize the classic symptoms and signs of aortic valve stenosis, especially in an adult. It is emphasized that all the classic signs rarely are present and their absence may mislead an unwary clinician. The diagnostic help provided by noninvasive tests, including echocardiography and phonocardiography, has been emphasized. A need for cardiac catheterization and angiography in most patients prior to corrective surgery is stressed. The natural history of the disease without operative intervention is dim and a significant risk of sudden death exists. The current surgical approach with immediate and long-term results is summarized. Finally, attention has been drawn to the special clinical circumstances when the aortic valve stenosis provides a strinkingly different clinical picture. We cannot find a better way to end this review than by quoting a warning note given by Thomas Lewis in 1920: "It is the faint cry of an anguished and fast failing muscle, which, when it comes, all should strain to hear, for it is not long repeated. A few months, a few years at most, and the end comes." 相似文献
86.
The low-resolution (2 nm) subunit symmetry of cucurbitin, the crystalline seed storage globulin of cucurbits, has been determined by X-ray diffraction. The wet crystals belong to the cubic space group F23 and there are 4 molecules per unit cell. The molecules therefore possess point-group symmetry 23 and contain 12 structural units which at this resolution are indistinguishable. On drying, the crystal lattice dimension shrinks from 13.6 nm to 12.4 nm with no apparent change in symmetry. Diffraction patterns of small crystals spun into a pellet, and sections of dry and wet native seed indicate that in situ the protein is organised in microcrystals of the same unit cell and symmetry. Edestin, the crystalline storage globulin from cannabis, and a crystalline globulin from tobacco seed both have the same crystal lattice as cucurbitin and, very likely, the same subunit symmetry. 相似文献
87.
We propose a new class of channel allocation algorithms that are simple, robust and require no communication between interfering WLANs. We show they are provably correct and yet remarkably efficient under a wide range of network conditions and topologies. The algorithms are suited to implementation on standard equipment, requiring no special hardware support and making only light demands on computational resources. We demonstrate this by implementing algorithms on an experimental testbed using commodity hardware. We present detailed measurements of performance in a real office environment. This environment includes complex spatially-varying noise, channel-dependent interference between WLANs, time-varying channel quality and external interference sources. Despite these challenges the algorithm performs well. 相似文献
88.
Using the attainable region approach, feasible compositions and conversions for random copolymers are determined, along with altermatives for the related reactor configurations. This analysis attempts to find all of the possible compositions that can be produced by any system of reactros and mixing. The average copolymer compositions are bounded by the feed composition and the instantaneous copolymer composition produced at the initial conditions. Since the instantaneous copolymer composition can be found through the Mayo‐Lewis equation, that case and the feed composition mark the limiting feasible compositions. The results can also be used to determine the range of feed compositions for which a specific copolymer product composition is possible. If the addition of monomer at any point in the reactor system is possible, e.g., by side‐feeding, the analysis indicates that any desired copolymer composition can be obtained. 相似文献
89.
90.
Kelly RM Meyer JD Matsuura JE Shefter E Hart MJ Malone DJ Manning MC 《Drug development and industrial pharmacy》1999,25(1):15-20
For certain patients who experience intense vertigo arising from unilateral vestibular lesions, the primary therapy is a vestibular nerve section, an intracranial surgical procedure. One alternative to this treatment is therapeutic ablation of vestibular function on the unaffected side using an ototoxic agent. We prepared a biodegradable sustained-release gel delivery system using sodium hyaluronate that can be administered into the middle ear using only a local anesthetic. The gel contains gentamycin sulfate, the ototoxic agent of choice for treatment of unilateral vestibulopathy, and it exhibits diffusion-controlled release of the drug over a period of hours. The released gentamycin could then diffuse into the inner ear through the round membrane. This represents an important advance over previous formulations, which used only gentamycin sulfate solutions, in that it should allow more careful control of the dose, it should reduce loss of the drug from the middle ear site, and it should maintain intimate contact with the round membrane. By carefully controlling the dose, it should be possible to inhibit vestibular function while minimizing hearing loss. Herein we describe the in vitro release kinetics of gentamycin sulfate from sodium hyaluronate gels and find that the system obeys Fickian behavior. 相似文献