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61.
The goal of stress incontinence surgery is to prevent opening of the urethra during increases in intra-abdominal pressure. Greater refinements in the understanding of the pathophysiology of incontinence and experience with newer treatments have extended surgical thinking beyond the familiar paradigm "to place the urethra in a high retropubic position." When incontinence is associated with vaginal hypermobility, vaginal support may be sufficient to restore continence if the suburethral vaginal wall is sufficiently strong, an evaluation which must often be made by physical examination alone. However, when the vaginal wall is weak, the urethra will require an alternative form of support, usually a sling. If the urethra is intrinsically deficient, vaginal support may not be sufficient to prevent opening during increased intra-abdominal pressure, and coaptation by sling obstruction or periurethral bulking injection may be required. Most laparoscopic approaches to stress incontinence use Burch's method, which offers excellent urethral stability provided the suburethral vaginal wall is strong. Newer insights into the relation between vaginal mobility and urethral closure are discussed, as well as anatomic aspects of the Burch suspension relevant to laparoscopic repair. 相似文献
62.
Ammar Mohemmed Mark Johnston Mengjie Zhang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(9):1793-1805
This paper proposes a new approach to using particle swarm optimisation (PSO) within an AdaBoost framework for object detection.
Instead of using exhaustive search for finding good features to be used for constructing weak classifiers in AdaBoost, we
propose two methods based on PSO. The first uses PSO to evolve and select good features only, and the weak classifiers use
a simple decision stump. The second uses PSO for both selecting good features and evolving weak classifiers in parallel. These
two methods are examined and compared on two challenging object detection tasks in images: detection of individual pasta pieces
and detection of a face. The experimental results suggest that both approaches can successfully detect object positions and
that using PSO for selecting good individual features and evolving associated weak classifiers in AdaBoost is more effective
than for selecting features only. We also show that PSO can evolve and select meaningful features in the face detection task. 相似文献
63.
Performing and composing for interactive audiovisual system presents many challenges to the performer. Working with visual, sonic and gestural components requires new skills and new ways of thinking about performance. However, there are few studies that focus on performer experience with interactive systems. We present the work Blue Space for oboe and interactive audiovisual system, highlighting the evolving process of the collaborative development of the work. We consider how musical and technical demands interact in this process, and outline the challenges of performing with interactive systems. Using the development of Blue Space as a self-reflective case study, we examine the role of gestures in interactive audiovisual works and identify new modes of performance. 相似文献
64.
Hospital foodservice directors & dietitians are facing the greatest challenge of their careers -- to prepare, along with their institutions, for the most thoroughgoing reform of America's healthcare system ever proposed. Healthcare institutions across the country are seeking the means to offer enhanced patient services & gain competitive advantages by forming new alliances, new patient-centered care systems & cost-reduction programs. To aid in these efforts, their foodservices are developing comprehensive cross-training schemes, inter-departmental teams with other service groups & new ways to cut operating subsidies. Here's how five hospital foodservice departments are using cost controls, revenue building, quality management processes & enhanced efficiencies to help their institutions prepare for the changes ahead. 相似文献
65.
"Ondol" is a Korean unique heating system. It is a specific radiant floor heating system using combustion heat of briquette or timber in Korea. Such traditional "Ondol" is changed to radiant heating system with pipe-coil embedded in the floor or slab. This study has contributed to the understandings of the transient behaviours of Ondol-heated floor panels and enclosure exposed to this type of heating system. The result is that the water supply temperature had a large effect on the rate of increase in floor surface and room air temperature. But, in spite of a higher water supply temperature, the heat flow rate was not increased considerably. The shallow pipe embedding depths, of course, result in a low heat flow rate. 相似文献
66.
Magnetization measurements are reported for seven members of the series of compounds RE
x
Mo
6
Se
8
(x1; RE=La, Ce, Pr, Eu, Gd, Yb, and Lu). These measurements establish that Ce, Pr, and Gd ions are trivalent in these compounds, but that Eu and Yb are primarily divalent, in agreement with crystallographic data. Large deviations of the susceptibilities for CeMo
6
Se
8
, PrMo
6
Se
8
, and YbMo
6
Se
8
from Curie-Weiss behavior above 10 K are attributed predominantly to crystal field effects, and quantitative agreement between crystal field theory and the experimental data was obtained for CeMo
6
Se
8
above 25 K. Further, we find for Gd
1.2
Mo
6
Se
8
an unusually small spin exchange interaction between the Gd ions and conduction electrons, consistent with previous estimates of this quantity based on superconductivity data. For the Gd, Eu, and Ce compounds, the low-temperature data indicate very small Curie-Weiss temperatures of –1.7, –0.6, and +0.4 K, respectively. No evidence for magnetic ordering of the RE ions in any of the above compounds was observed, with the exception of CeMo
6
Se
8
, for which the magnetization data at 0.7–1.3 K suggest the onset of ferromagnetic order.Research sponsored by the Air Force Office of Scientific Research, Air Force Systems Command, USAF, under AFOSR Contract No. AFOSR/F-44620-72-C-0017. 相似文献
67.
68.
Water Resource Models in the Mekong Basin: A Review 总被引:6,自引:1,他引:5
Development of the water resources of the Mekong Basin is the subject of intense debate both within the Mekong region and
internationally. Water resources modelling is playing an increasingly important role in the debate, with significant effort
in building integrated modelling platforms to describe the hydrological, ecological, social and economic impacts of water
resource development. In the hydrological domain, a comprehensive set of models has been effective in building understanding
of the system, and in identifying and describing the issues and trade-offs involved in basin-scale water planning. In the
ecological and social domains, quantitative modelling has not progressed very far; geo-spatial analysis and qualitative frameworks
remain the most commonly used tools. Economic models have been used to assess the costs and benefits of water resources development
and to describe the trade-offs between different sectors and users. These analyses are likely to play an important role in
the policy and planning debate, but are hampered by uncertainties in valuation of ecosystem services. Future efforts should
focus on optimising the use of existing model platforms for the Mekong, including structured comparison of multiple hydrological
models to quantify errors and identify an optimum set of modelling tools for different applications. A comprehensive research
effort is needed to incorporate groundwater into hydrological models for regional planning. Options for social impact assessment
should be reassessed before major investments are made in complex modelling platforms, and participatory social survey methods
evaluated as part of an integrated assessment framework. 相似文献
69.
D. C. Johnston 《Journal of Low Temperature Physics》1976,25(1-2):145-175
LiTi
2
O
4
is one end member of the homogeneity range of the spinel phase Li
1+x
Ti
2–x
O
4
(0x1/3) and is superconducting at temperatures up to 13.7 K. Various measurements were carried out in order to characterize the superconducting and normal state properties of LiTi
2
O
4
and of other compositions within the homogeneity range of the spinel phase. These measurements establish LiTi
2
O
4
as ad-band superconductor and show thatT
c
decreases to <1.5 K forx0.1. This disappearance of superconductivity with increasingx was found to be correlated with anomalous changes in the lattice parameter with composition, and, from electrical resistivity measurements, is tentatively attributed to the occurrence of a composition-induced metal-semiconductor transition atx0.1. The metallic character of LiTi
2
O
4
and the composition dependence of the observed electrical properties are shown to follow from crystallographic considerations.Research sponsored by the Air Force Office of Scientific Research, Air Force Systems Command, USAF, under AFOSR Contract Number AFOSR/F-44620-C-0017. 相似文献
70.
The mechanism(s) of insulin resistance in non-insulin-dependent diabetes mellitus remains ill defined. The current studies sought to determine whether non-insulin-dependent diabetes mellitus is associated with (a) a delay in the rate of onset of insulin action, (b) impaired hepatic and extrahepatic kinetic responses to insulin, and (c) an alteration in the contribution of gluconeogenesis to hepatic glucose release. To answer these questions, glucose disappearance, glucose release, and the rate of incorporation of 14CO2 into glucose were measured during 0.5 and 1.0 mU/kg-1 per min-1 insulin infusions while glucose was clamped at approximately 95 mg/dl in diabetic and nondiabetic subjects. The absolute rate of disappearance was lower (P < 0.05) and the rate of increase slower (P < 0.05) in diabetic than nondiabetic subjects during both insulin infusions. In contrast, the rate of suppression of glucose release in response to a change in insulin did not differ in the diabetic and nondiabetic subjects during either the low (slope 30-240 min:0.02 +/- 0.01 vs 0.02 +/- 0.01) or high (0.02 +/- 0.00 vs 0.02 +/- 0.00) insulin infusions. However, the hepatic response to insulin was not entirely normal in the diabetic subjects. Both glucose release and the proportion of systemic glucose being derived from 14CO2 (an index of gluconeogenesis) was inappropriately high for the prevailing insulin concentration in the diabetic subjects. Thus non-insulin-dependent diabetes mellitus slows the rate-limiting step in insulin action in muscle but not liver and alters the relative contribution of gluconeogenesis and glycogenolysis to hepatic glucose release. 相似文献