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61.
MR Ujhelyi AP Winecoff M Schur T Frede MB Bottorff M Gabel ML Markel 《Canadian Metallurgical Quarterly》1996,110(3):784-790
BACKGROUND: Transplantation of lung allografts from the same donor into 2 recipients ("twinning") provides an opportunity to study recipient and donor factors that influence early allograft function. METHODS: Twenty-seven pairs of recipients were identified and evaluated using multivariate logistic regression analysis (p < 0.05). Four measures of early graft function were analyzed: alveolar-arterial gradient in the operating room, first alveolar-arterial gradient in the intensive care unit, alveolar-arterial gradient at 24 hours, and days of mechanical ventilation. RESULTS: Analysis of the pooled data without regard to pairing showed that alveolar-arterial gradient in the operating room was influenced by donor age, length of donor hospitalization, recipient mean pulmonary artery (PA) pressure at unclamping, and transplantation of a left lung. The alveolar-arterial gradient in the intensive care unit was correlated with donor age, donor cause of death, and mean PA pressure on arrival in that unit. Only mean PA pressure remained significant at 24 hours. Days of mechanical ventilation was determined by mean PA pressure on arrival in the intensive care unit, drop in mean PA pressure during operation, and diagnosis of the recipient. In the paired analysis, receiving a left lung, recipient diagnosis (pulmonary hypertension worse than others), and need of cardiopulmonary bypass were significantly associated with immediate graft dysfunction, although these influences did not persist beyond the immediate postoperative period. Donor arterial oxygen tension and time of ischemia were not significant predictors in any analysis. CONCLUSIONS: Immediate allograft function was associated with donor-related characteristics initially, but these lost importance over the ensuing 24 hours. Recipient PA pressure was an immediate and persisting influence. In the analysis of differences in function between the members of each pair, transplantation of the left lung, recipient diagnosis, and cardiopulmonary bypass were identified, but their influence did not persist beyond the first 6 hours. 相似文献
62.
T Watanabe DA Rivas R Smith WE Staas MB Chancellor 《Canadian Metallurgical Quarterly》1996,156(6):1926-1928
PURPOSE: We investigated the changes in sexuality and quality of life that evolve after lower urinary tract reconstruction in neurologically impaired women previously treated with an indwelling urethral catheter. MATERIALS AND METHODS: A total of 18 neurologically impaired women treated with an indwelling urethral catheter underwent bladder reconstruction. Pubovaginal sling urethral compression was required to restore perineal dryness in 13 patients and was the only operation required in conjunction with intermittent catheterization in 3. Eight patients underwent ileocystostomy, that is creation of a "bladder chimney," and 4 underwent augmentation cystoplasty with creation of a continent catheterizable stoma. In 3 patients ileocystoplasty alone with intermittent urethral catheterization was performed. All patients were followed 6 to 40 months (mean 18) after reconstructive surgery using a 9-part questionnaire to score numerically the effect of surgical reconstruction on sexuality and quality of life issues. RESULTS: On a scale of 0 (worst) to 5 (best) mean score for self-esteem improved from 1 preoperatively to 4 postoperatively, self-image from 1 to 4, sexual desire from 2 to 4 and ability to cope with disability from 1 to 4, respectively. In 4 of the 15 women who were sexually active preoperatively the frequency of sexual intercourse doubled from a mean of 3 to 6 times per month, respectively, and all 4 women reported improved sexual satisfaction. All 13 patients with pelvic pain and 5 with symptoms of autonomic dysreflexia noticed significant improvement if not complete resolution of the symptoms. CONCLUSIONS: Neurogenic lower urinary tract dysfunction treated with an indwelling urethral catheter is detrimental to sexuality and quality of life in neurologically impaired women. Urinary tract reconstruction restores not only quality of life but also sexuality by improving self-image, self-esteem and the ability to cope. Indwelling catheterization as a method of long-term urinary treatment should be avoided in women. 相似文献
63.
Y. Moser R. Forti S. Jiguet T. Lehnert M. A. M. Gijs 《Microfluidics and nanofluidics》2011,10(1):219-224
SU-8 photoresist is commonly used in the field of microfabrication as structural material or for molding of microfluidic devices.
One major limitation, however, is the difficulty to process partially freestanding SU-8 structures or monolithic closed cavities
and channels on-chip. We propose here a simple method for the fabrication of suspended structures, in particular of monolithic
SU-8 microchannels. The method is based on the processing of a SU-8 double-layer. Appropriate modification of the optical
properties of the upper layer allows for selective crosslinking in the layer sandwich. This process is suitable for versatile
layouts comprising open and hollow SU-8 structures on the same chip. 相似文献
64.
Coping with information overload in email communication: Evaluation of a training intervention 总被引:2,自引:0,他引:2
The present paper introduces three facets of information overload in email communication: A large amount of incoming information, inefficient workflow, and deficient communication quality. In order to cope with these facets of information overload, a training intervention was developed and evaluated. Data were collected from 90 employees on several evaluation levels within a longitudinal evaluation design (one pretest double posttest design). The results reveal that the training contributed to an increase in knowledge and media competencies. We also found evidence for a transfer of training contents to the workplace. Finally, strain diminished on several dimensions. In particular, problems with media usage and work impairment decline significantly, an effect that was stronger for those participants who face a large amount of email at their workplaces. 相似文献
65.
Falk Hüffner Christian Komusiewicz Hannes Moser Rolf Niedermeier 《Theory of Computing Systems》2010,47(1):196-217
We initiate the first systematic study of the NP-hard Cluster Vertex Deletion (CVD) problem (unweighted and weighted) in terms of fixed-parameter algorithmics. In the unweighted case, one searches for a minimum
number of vertex deletions to transform a graph into a collection of disjoint cliques. The parameter is the number of vertex
deletions. We present efficient fixed-parameter algorithms for CVD applying the fairly new iterative compression technique.
Moreover, we study the variant of CVD where the maximum number of cliques to be generated is prespecified. Here, we exploit
connections to fixed-parameter algorithms for (weighted) Vertex Cover. 相似文献
66.
To contribute to the current effort toward the definition of a system-level design language, this article proposes a benchmark for system specification. The authors analyze the results of experiments using the benchmark with several languages 相似文献
67.
Wenbing Zhao Moser L.E. Melliar-Smith P.M. 《Parallel and Distributed Systems, IEEE Transactions on》2008,19(2):188-203
With the advent of the new generation of Internet-based technology, in particular, web services, the automation of business activities that are distributed across multiple enterprises becomes possible. Business activities are different from traditional transactions in that they are typically asynchronous, loosely coupled, and long running. Therefore, extended transaction protocols are needed to coordinate business activities that span multiple enterprises. Existing extended transaction protocols typically rely on compensating transactions to handle exceptional conditions. In this paper, we identify a number of issues with compensation-based extended transaction protocols and describe a reservation-based extended transaction protocol that addresses those issues. Moreover, we define a set of properties, analogous to the ACID properties of traditional transactions that are more appropriate for business activities that span multiple enterprises. In addition, we compare our reservation protocol with other extended transaction protocols for coordinating business activities and present performance analyses and results. 相似文献
68.
Real-time scheduling for energy harvesting sensor nodes 总被引:1,自引:1,他引:0
Energy harvesting has recently emerged as a feasible option to increase the operating time of sensor networks. If each node
of the network, however, is powered by a fluctuating energy source, common power management solutions have to be reconceived.
This holds in particular if real-time responsiveness of a given application has to be guaranteed. Task scheduling at the single
nodes should account for the properties of the energy source, capacity of the energy storage as well as deadlines of the single
tasks. We show that conventional scheduling algorithms (like e.g. EDF) are not suitable for this scenario. Based on this motivation,
we have constructed optimal scheduling algorithms that jointly handle constraints from both energy and time domain. Further
we present an admittance test that decides for arbitrary task sets, whether they can be scheduled without deadline violations.
To this end, we introduce the concept of energy variability characterization curves (EVCC) which nicely captures the dynamics
of various energy sources. Simulation results show that our algorithms allow significant reductions of the battery size compared
to Earliest Deadline First scheduling.
相似文献
Clemens MoserEmail: |
69.
Two bacteriophages were isolated from field collected samples representing two different mosquito breeding places. The phage AB-1 (isolated from Abheit village, Faiyoum Governorate "seepage water") and the phage GA-2 (isolated from El-Gabal El-Asfer Qualyobia Governorate "sewage drain water") were purified. Both bacteriophages were ultrastructurally described with respect to their morphology, dimensions, phases of bacterial attack and lysogeny. No major differences were observed between both isolated phages in relation to specificity, however; they were isolated from two different types of breeding places and two different geographic areas as well. This study may assume a wide host range of the isolated phages and reflect how bacterial insecticides used for mosquito larval control could be inhibited by such bacteriophage. 相似文献
70.
This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial selection of input files and graphic display of modeling output. Data for testing and running the model came from the U.S. Forest Service's Forest Inventory and Analysis (FIA) Database and were also collected in field surveys in north-central Indiana. ArcFVS 1.0 is designed using the ArcGIS software from the Environmental Systems Research Institute (ESRI) and the Visual Basic for Applications (VBA) programming environment to manipulate ESRI's ArcObjects. The resulting product offers custom functions as commands in a new menu or as tools on a new toolbar. They are used to: select spatially or by attribute the forest plots to be projected by FVS, create the FVS input files for the selected plots and display in a geospatial environment different types of FVS output (text output files, tables with variables of interest and visualization image files). Advantages of ArcFVS 1.0 include the new GIS capabilities, enhanced format translation functions and the standardized programming environment. 相似文献