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1.
Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy.  相似文献   
2.
BACKGROUND: Classification of patients with chronic whiplash associated disorders (WAD) into homogenous subgroups is an important objective in order to tailor interventions and to control for subgroup differences when evaluating treatment outcome. AIMS: The aims of this study were to investigate if it was possible to replicate and describe the three cluster solution and profiles found in other pain groups and describe cluster profiles based on self-reported Multidimensional Pain Inventory-scores for patients with WAD three months after the injury, describe characteristics of the clusters in relation to disability, self-efficacy and coping at the same point in time and to validate the cluster solution by comparing clusters in disability, self-efficacy and coping over time. METHODS: Ninety-one WAD-patients three months after the accident took part in the study. The measures used were the Multidimensional Pain Inventory-Swedish version (MPI-S), The Self-Efficacy Scale, The Coping Strategies Questionnaire and The Pain Disability Index. Cluster analysis was conducted for the total sample MPI-S subscale scores. RESULTS: The adaptive copers cluster represented 42% of the sample, dysfunctional 34% of the sample, and interpersonally distressed 24% of the sample. The external validation of cluster solution showed that there were several significant differences between clusters in self-efficacy, disability and coping measures. There was also a significant interaction effect (clusterxtime) in disability (PDI). Patients in dysfunctional cluster reported a decreased disability over time. CONCLUSIONS: These results support the presence of different subgroups among patients with whiplash associated disorders. This classification can be seen as a complement to a classification based on medical condition.  相似文献   
3.
This study applied zero-delay wave number spectral estimation as a means of quantifying the changes in activation and recovery sequences of propagating plane waves on the epicardial surface of in situ porcine hearts during regional hyperkalemia and ischemia. Unipolar electrograms (104) were recorded from the left ventricular surface of nine hearts using a plaque electrode array with 1 mm spatial sampling intervals. The objectives were (1) to define a set of parameters capable of quantifying the spatial and temporal changes in measured extracellular potentials associated with localized ischemia prior to the onset of conduction block; (2) to elevate regional levels of extracellular potassium ion concentration and quantify potential changes due to this known physiologic manipulation; and (3) to use quantitative parameters to make statistical comparisons in order to distinguish wave fronts during normal, ischemic and hyperkalemic conditions. Results showed that the parameters of wave number and average temporal frequency and the associated power, as determined from the wave number spectrum, provided statistically significant (p < 0.05) quantification of changes in wave front features during normal and ischemic or hyperkalemic conditions. The results were consistent with results obtained from conventional time–space domain methods like isochronal mapping and electrograms, with the advantage of a quantitative result enabling simple comparisons and trend analysis for large numbers of heart beats. © 1998 Biomedical Engineering Society. PAC98: 8759Wc, 8722Fy, 8780+s  相似文献   
4.
Sixteen obese patients, aged 19–31, and 27 normal weight individuals, aged 18–22, tasted and smelled fresh, unseasoned blended foods while blindfolded. Then they rated the foods on 51 semantic differential adjective scales which related to stimulation of the gustatory, olfactory, and trigeminal systems. The stimuli included fruits, vegetables, meat, fish, nuts, dairy products, grains, and a set of four standards: sucrose (sweet), NaCl (salty), lemon (sour), and coffee (bitter) in a thin cornstarch base. Proximity measures among stimuli for each subject were developed from the ratings on the adjective scales. Two multidimensional scaling (MDS) procedures, SINDSCAL (a variation of INDSCAL) and ALSCAL, were applied to the proximity measures yielding two-dimensional food maps which were very similar. Both MDS procedures provided weights for each subject on the two dimensions of the space common for all subjects. The weights indicated that the obese subjects found the first dimension, which was related to the hedonic and flavorous aspects of the stimuli, relatively more important than normal weight individuals. Also, obese subjects were significantly better at identifying the blended foods when compared to normal weight subjects.  相似文献   
5.
中文Frost多维度完美主义问卷的信效度检验   总被引:24,自引:1,他引:24  
目的:检验中文Frost多维度完美主义问卷(FMPS)信效度。方法:共有1280名大学本科生作为被试填写了FMPS问卷,其1000名被试的数据用于探索性因素分析,另外280名被试的数据用于验证性因素分析。部分被试被要求填写测量焦虑、抑郁、强迫等心理困扰的问卷,作为效标效度检验。结果:中文版Frost多维度完美主义问卷由五个维度组成。各维度的项目载荷在0.45—0.78之间。五个因素(担心错误、条理性、父母期望、个人标准和行动的疑虑)可以解释总方差的53.7%。各维度的内部一致性系数为0.64-0.81。重测信度为0.63-0.82。中文FMPS与焦虑、抑郁、强迫等心理困扰也有屉著的相关,其中“担心错误”和“行动的疑虑”与各种心理困扰的相关系数在0.30—0.70之间。结论:中文FMPS的维度结构与其英文原问卷相似,且具有令人满意的信效度。适合在中国文化环境下使用。  相似文献   
6.
目的探讨多维分层反馈模式在医院内部质量评价中的应用效果。方法选择江苏省盐城市某三甲综合医院为样本医院,以职能部门、临床科室、医技科室共89个考核单元为研究对象,开展医院内部质量评价活动,应用多维分层理念建立质评反馈模式。结果应用多维分层反馈模式后,办公室、医务科、沟通办等职能部门月度质评现场管理成绩均有所提升(P<0.05);职能部门(台账资料)、临床医疗、医技科室及护理单元季度质评成绩均有所提高(P<0.05);危化品、不良事件、便携式血糖仪、知情同意及时间管理等专项质评追踪合格率均显著提高(P<0.001)。结论将质评机制引入医院并形成科学化、常态化管理,是对外部评审的重要补充。而多维分层反馈模式的建立,有效地促进了部门、科室间的相互协作,提升了职能部门的管理成效,提高了医院整体的质量管理效能。  相似文献   
7.
ObjectiveData on prognostic tools for indicating mechanical ventilation in older people with COVID-19 are still limited. The aim of this research was to evaluate if the Multidimensional Prognostic Index (MPI), based on the Comprehensive Geriatric Assessment (CGA), may help physicians in identifying older hospitalized patients affected by COVID-19 who might benefit from mechanical ventilation.DesignLongitudinal, multicenter study.Settings and Participants502 older people hospitalized for COVID-19 in 10 European hospitals.MethodsMPI was calculated using 8 different domains typical of the CGA. A propensity score, Cox's regression analysis was used for assessing the impact of mechanical ventilation on rehospitalization/mortality for 90 days' follow-up, stratified by MPI = 0.50. The accuracy of MPI in predicting negative outcomes (ie, rehospitalization/mortality) was assessed using the area under the curve (AUC), and the discrimination with several indexes like the Net Reclassification Improvement (NRI) and the Integrated Discrimination Improvement (IDI).ResultsAmong 502 older people hospitalized for COVID-19 (mean age: 80 years), 152 were treated with mechanical ventilation. In the propensity score analysis, during the 90-day follow-up period, there were 44 rehospitalizations and 95 deaths. Mechanical ventilation in patients with MPI values ≥ 0.50, indicating frailer participants, was associated with a higher risk of rehospitalization/mortality (hazard ratio 1.56, 95% CI 1.09-2.23), whereas in participants with MPI values < 0.50 this association was not significant. The accuracy of the model including age, sex, respiratory parameters, and MPI was good (AUC = 0.783) as confirmed by an NRI of 0.2756 (P < .001) and an IDI of 0.1858 (P < .001), suggesting a good discrimination of the model in predicting negative outcomes.Conclusions and ImplicationsMPI could be useful for better individualizing older people hospitalized by COVID-19 who could benefit from mechanical ventilation.  相似文献   
8.
Attachment Q-Sort (AQS) is a tool for quantifying observations about toddler/caregiver relationships. Previous studies have applied factor analysis to the full 90 AQS item set to explore the structure underlying them. Here we explore that structure by applying multidimensional scaling (MDS) to judgements of inter-item similarity. AQS items are arranged in the MDS solution along three easily interpretable axes: a model that is compatible with but more parsimonious than factor analysis solutions. This geometrical approach suggests ways to modify the AQS—primarily a research tool—to make it more practical for clinical applications. Sets of AQS data are represented and interpreted in the three-dimensional model as vectors. Summaries at a finer-grained level are obtained by finding points in the model where variability across datasets is greatest. We report re-analyses of archival (published) data, and also data collected with streamlined procedures more suitable in the field. Although not reported here, collection and analysis can both be performed online via a website. The general methodology is not restricted to the current application of toddler attachment.  相似文献   
9.
Purpose of the studyThe prevalence of frailty is expected to increase worldwide in parallel with demographic ageing. Despite this, little is known about the prevalence in different populations particularly community-based samples. This cross-sectional study evaluates the prevalence of frailty in a community-dwelling older adult population and describes a methodology to plan community-based interventions.MethodologyA random sample of 1331 older adults, resident in the Lazio-Region of Italy, were screened by trained public health nurses (PHNs) by administering a validated questionnaire (the Functional Geriatric Evaluation questionnaire). Prevalence of frailty was calculated using the Final Synthetic Score derived from the questionnaire’s Final Score. Variables associated with frailty were selected through univariate and multivariate statistical analysis.ResultsPrevalence of frail (FS  10,≤50) and very frail (FS < 10) individuals was 13.9% and 7.6% respectively. Variables associated with frailty were age (older than 85 years), disability, living alone or the presence of a paid carer, lower education and neurological disorders like stroke, dementia, Parkinson disease and other neuropsychiatric diseases; Anaemia or cancer were also associated with a higher prevalence of frailty.DiscussionThe study provide a comprehensive picture of the prevalence of frailty and factors associated to this condition in community-dwelling older adults. On the basis of the study results, a plan of community-based services could address the needs of care of the elderly population. A trained team of PHNs may be the most appropriate personnel to carry out multidimensional frailty assessment in this setting.  相似文献   
10.
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