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981.
BACKGROUND: Fifty-three patients treated at a level I trauma center with iliac vessel injury were studied to determine if body temperature and acid-base status in the operating room predicts outcome. METHODS: Records were reviewed for demographics, mechanism of injury, body temperature, acid-base status, operative management, and outcome. Statistical methods included Student's t test, odds ratio determination, and chi-square analysis to determine statistical significance. RESULTS: Fifty-three patients (47 male, 6 female) sustained 92 iliac vascular injuries (36 arterial, 56 venous). Mortality was 34%, with 72% of deaths due to shock within 24 hours. Physiologic parameters differed significantly between survivors and nonsurvivors. Odds ratio identified six conditions; the number present predicted outcome. CONCLUSIONS: (1) There are significant differences between initial and final operating room temperature and acid-base status in survivors versus nonsurvivors with iliac vessel injury. Conditions for odds ratio can be calculated and correlated with outcome. (2) A patient with two or more conditions should be considered for an abbreviated laparotomy to allow for reversal of "physiologic failure."  相似文献   
982.
Forty-two patients who had a Porous Coated Anatomic (PCA) "E" series, second-generation, cementless hip arthroplasty (Howmedica, Rutherford, NJ) were compared with 42 patients who had a first-generation PCA prosthesis. Patients were directly matched for age, sex, diagnosis, weight, Charnley functional status, and duration of follow-up. All of the operations were done by the same two surgeons, who used the same operative approach and the same postoperative rehabilitation plan. All of the patients were followed up for at least 5 years (range, 60 to 76 months). In the "E" series group, there were 41 of 42 (98%) good and excellent clinical results with a mean Harris hip score of 94 points (range, 46 to 100 points); the first-generation group had 34 of 42 (81%) good and excellent clinical results and a mean Harris score of 81 points (range, 42 to 100 points) (P = 0.001). There was one acetabular component revision in the "E" series group (2%), which can be compared with eight revisions (19%) in the first-generation group (P = 0.012). The incidence of femoral radiolucencies was 19% (eight hips) for the "E" series group compared with 50% (21 hips) in the first-generation group (P = 0.009). The radiolucencies in the "E" series group were small, nonprogressive, and confined typically to zone I. We believe that the improvements in design of the "E" series component may account for these differences.  相似文献   
983.
This paper reviews the OpenLogos rule-based machine translation system, and describes its model architecture as an incremental pipeline process. The paper also describes OpenLogos resources and their customization to specific application domains. One of the key aspects of rule-based machine translation systems intelligence is the symbology employed by these systems in representing natural language internally. The paper offers details about the OpenLogos semantico-syntactic abstract representation language known as SAL. The paper also shows how OpenLogos has addressed classic problems of rule-based machine translation, such as the cognitive complexity and ambiguity encountered in natural language processing, illustrating how SAL helps overcome them in ways distinct from other existing rule-based machine translation systems. The paper illustrates how the intelligence inherent in SAL contributes to translation quality, presenting examples of OpenLogos output of a kind that non-linguistic systems would likely have difficulty emulating. The paper shows the unique manner in which OpenLogos applies the rulebase to the input stream and the kind of results produced that are characteristic of the OpenLogos output. Finally, the paper deals with an important advantage of rule-based machine translation systems, namely, the customization and adaption to application-specific needs with respect to their special terminology and transfer requirements. OpenLogos offers users a set of comfortable customization tools that do not require special knowledge of the system internals. An overview of the possibilities that these tools provide will be presented.  相似文献   
984.
Dissolved oxygen (DO) concentration is a key indicator of the health and productivity of an aquatic ecosystem. This paper presents a new method for high‐resolution characterization of DO as a function of both space and time. The implementation of a new oxygen optode in an Iver2 autonomous underwater vehicle (AUV) is described, which enables the system to measure both absolute oxygen concentration and percentage saturation. Also described are details of AUV missions in Hopavågen Bay, Norway, which consisted of a series of repeated undulating lawnmower patterns that covered the bay. Through offline postprocessing of data, sensor characteristic models were developed, as well as a 3D lattice time series model. The model was constructed by estimating DO at each 3D lattice node location using a 1D Kalman filter that fused local measurements obtained with the AUV. By repeating model construction for several missions that spanned 24 h, estimates of DO as a function of space and time were calculated. Results demonstrated (1) the AUVs ability to repeatedly gather high‐spatial‐resolution data (2) significant spatial and temporal variation in DO in the water body investigated, and (3) that a 3D model of DO provides better estimates of total DO in a volume than extrapolating from only a single 2D plane. Given the importance of oxygen within an ecosystem, this new method of estimating the quantity of DO per volume has the potential to become a reliable test for the health of an underwater ecosystem. Also, it can be refined for detecting and monitoring a range of soluble gases and dispersed particles in aquatic environments, such as dissolved O2 and CO2 around production facilities such as fish farms, or dispersed hydrocarbons and other pollutants in fragile ecosystems. © 2012 Wiley Periodicals, Inc.  相似文献   
985.
We present a rationale for a selection of tools that assist developers of hard real-time applications to verify that programs conform to a Java real-time profile and that platform-specific resource constraints are satisfied. These tools are specialised instances of more generic static analysis and model checking frameworks. The concepts are illustrated by two case studies, and the strengths and the limitations of the tools are discussed.  相似文献   
986.
Chemical vapor deposition (CVD) and metal-organic chemical vapor deposition (MOCVD) have been employed to develop alumina thin films in order to protect thermocouples from catalytic overheating in flames and to minimize the intrusion presented to the combustion process. Alumina films obtained with a CVD process using AlCl(3) as the precursor are dense, not contaminated, and crystallize in the corundum structure, while MOCVD using Al(acetyl acetone)(3) allows the growth of corundum alumina with improved growth rates. These films, however, present a porous columnar structure and show some carbon contamination. Therefore, coated thermocouples using AlCl(3)-CVD were judged more suitable for flame temperature measurements and were tested in different fuels over a typical range of stoichiometries. Coated thermocouples exhibit satisfactory measurement reproducibility, no temporal drifts, and do not suffer from catalytic effects. Furthermore, their increased radiative heat loss (observed by infrared spectroscopy) allows temperature measurements over a wider range when compared to uncoated thermocouples. A flame with a well-known temperature profile established with laser-based techniques was used to determine the radiative heat loss correction to account for the difference between the apparent temperature measured by the coated thermocouple and the true flame temperature. The validity of the correction term was confirmed with temperature profile measurements for several flames previously studied in different laboratories with laser-based techniques.  相似文献   
987.
The article proposes an optimal design approach to minimize the mass of load carrying structures with discrete design variables. The design variables are chosen from catalogues, and several variables are assigned to each part of the structure. This allows for more design freedom than only choosing parts from a catalogue. The problems are modelled as mixed 0–1 nonlinear problems with nonconvex continuous relaxations. An algorithm based on outer approximation is proposed to find optimized designs. The capabilities of the approach are demonstrated by optimal design of a space frame (jacket) structure for offshore wind turbines, with requirements on natural frequencies, strength, and fatigue lifetime.  相似文献   
988.
Online communities can be an attractive source of ideas for product and process innovations. However, innovative user‐contributed ideas may be few. From a perspective of harnessing “big data” for inbound open innovation, the detection of good ideas in online communities is a problem of detecting rare events. Recent advances in text analytics and machine learning have made it possible to screen vast amounts of online information and automatically detect user‐contributed ideas. However, it is still uncertain whether the ideas identified by such systems will also be regarded as sufficiently novel, feasible and valuable by firms who might decide to develop them further. A validation study is reported in which 200 posts from an online home brewing community were extracted by an automatic idea detection system. Two professionals from a brewing company evaluated the posts in terms of idea content, idea novelty, idea feasibility and idea value. The results suggest that the automatic idea detection system is sufficiently valid to be deployed for the harvesting and initial screening of ideas, and that the profile of the identified ideas (in terms of novelty, feasibility and value) follows the same pattern identified in studies of user ideation in general.  相似文献   
989.
Glutamine amidotransferase (GAT) subunits or domains catalyzean important partial reaction in many complex biosynthetic reactions.The structure of one member of the F-type GATs is known, butthe structure of the unrelated G-type is still unknown. Becausemany protein sequences are available for anthranilate synthasecomponent II (product of the trpG gene), we have predicted itsaverage secondary structure by a joint prediction method [Niermannand Kirschner (1991a) Protein Engng, 4, 359–370]. Thepredicted eight ß-strands and seven -helices followan 8-fold cyclic repetition of a ß-strand-loop--helix-loopmodule with helix 7 missing. This pattern of secondary structuresuggests that the G-type GAT domain has an 8-fold ß-barreltopology, as found first in triose phosphate isomerase (TIM-barrel).This model is supported by the location of known catalyticallyessential residues in loops between (ß-strands and-helices. Evidence from published sequencing and mutationalstudies on selected members of the GAT superfamily (carbamoylphosphate, imidazoleglycerol phosphate, GMP and CTP synthases)support both the secondary structure prediction and the TIM-barreltopology.  相似文献   
990.
Marker allele-disease association and linkage between a disease locus and a marker locus are two different phenomena. Linkage without evidence of association and association without evidence of linkage are possible observations. Linkage analysis uses marker loci and the phenomenon of recombination to look for disease-related loci which are presumably major contributors to disease expression ("necessary" loci). However, the phenomenon of association is more complex. One explanation for the existence of an association is that there is a "necessary" locus in linkage disequilibrium with a marker locus. Another explanation is that the marker locus itself (or a closely linked locus in linkage disequilibrium with the marker) is a "susceptibility" locus, which increases the probability of contracting the disease but is not necessary for disease expression. Although there are other possible explanations for the existence of an association, these two can lead to different results when family data from a disease showing association are analyzed for linkage between the associated marker and the disease. If the linkage disequilibrium hypothesis is correct, there will be evidence for linkage. If the susceptibility locus hypothesis is correct, there may be strong evidence against linkage. In this work, we explore a method that could indicate whether an association is due to a susceptibility locus or a necessary locus. We show that, by dividing families based on the presence or absence of the associated marker allele in a randomly chosen affected sib, calculating lod scores, and then calculating a heterogeneity statistic, we could distinguish whether linkage data came from a susceptibility locus or a necessary locus.  相似文献   
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