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31.
Shawn L. Nissen Richard W. Harris Lara-Jill Jennings Dennis L. Eggett Holly Buck 《International journal of audiology》2013,52(7):379-390
The purpose of this study was to develop, digitally record, evaluate, and psychometrically equate a set of Mandarin bisyllabic word lists for use in measurement of speech discrimination. Familiar bisyllabic words were digitally recorded by male and female talkers of Standard Mandarin. Percentage of correct word recognition was measured for each word at ten intensity levels (?5 to 40 dB HL) in 5 dB increments using 20 normally hearing subjects. Using logistic regression, 200 words with the steepest logistic regression slopes were included in four psychometrically equivalent word lists of 50 words each, and eight half-lists of 25 words each. To increase auditory homogeneity of the lists, the intensity of words in each list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists. Digital recordings of the psychometrically equivalent word recognition lists are available on compact disc. 相似文献
32.
The matching of groups is a traditional way to control for confounding variables in developmental disabilities research. The equivalency of means across groups is routinely checked for these variables, but not the homogeneity of their variances or the shapes of their distributions. In the present paper, it is argued that group matching can go seriously wrong unless it directly confronts the distributional concerns by the use of well-known statistical indices and very simple graphical displays of the distributions. The question of the equivalency of item response profiles is also addressed since two participants or two groups of participants can obtain the same overall score on the matching variable by passing different items. In this case, the matching cannot be considered satisfactory because of poor concordance between the molar (overall score) and molecular (item scores) levels of matching. Angoff's Delta plot method, a statistical approach for detecting differential item functioning across small groups is described. It is promising as a simple way to prove whole test/individual item correspondence and, in addition, a useful tool for making post hoc statistical analyses at the item level on the dependent variables. 相似文献
33.
The goal of the two-sample test (a.k.a. the homogeneity test) is, given two sets of samples, to judge whether the probability distributions behind the samples are the same or not. In this paper, we propose a novel non-parametric method of two-sample test based on a least-squares density ratio estimator. Through various experiments, we show that the proposed method overall produces smaller type-II error (i.e., the probability of judging the two distributions to be the same when they are actually different) than a state-of-the-art method, with slightly larger type-I error (i.e., the probability of judging the two distributions to be different when they are actually the same). 相似文献
34.
Zhang Z Liu Y Jiang T Zhou B An N Dai H Wang P Niu Y Wang L Zhang X 《NeuroImage》2012,59(2):1429-1440
Alzheimer's disease (AD), the most prevalent cause of dementia in the elderly, is characterized by progressive cognitive and intellectual deficits. Most patients with mild cognitive impairment (MCI) are thought to be in a very early stage of AD. Resting-state functional magnetic resonance imaging reflects spontaneous brain activities and/or the endogenous/background neurophysiological process of the human brain. Regional Homogeneity (ReHo) can provide a fast method for mapping regional activity across the whole brain. Little has been previously published about where or how spontaneous activity differs between MCI and AD, although many previous fMRI studies have shown that the activity pattern is altered in MCI/AD. In the present study, we first used the ReHo method to explore differences in regional spontaneous activities throughout the whole brain between normal controls (NC) and people with MCI and with AD. A one-way ANOVA was performed to determine the regions in which the ReHo differs between the three groups, and then a post hoc analysis was performed to evaluate differences in the pattern among the three groups. Finally a correlation analysis was done between the ReHo index of these regions and clinical variables in order to evaluate the relationship between ReHo and cognitive measures in the AD and MCI groups. An exploratory classification analysis also demonstrated that ReHo measures were able to correctly separate subjects in 71.4% of the cases. Altered brain spontaneous activations were found in the medial prefrontal cortex, the bilateral posterior cingulate gyrus/precuneus and the left inferior parietal lobule (IPL) in both MCI and AD. In MCI, the ReHo index in the left IPL was higher than that of the NC, which could indicate the presence of a compensatory mechanism in MCI. More obviously, the correlation analysis indicated that the lower the memory and other cognitive abilities, the lower the ReHo in patients with MCI and AD. Combining our findings with the results in earlier studies, we propose that the spontaneous activity pattern in the resting state could potentially be used as a clinical marker for MCI/AD. 相似文献
35.
目的 构建国内专科护士同质化培训管理方案,探讨应用效果,以提升专科护士的培训质量。方法 2020年1月—2021年12月,采用方便抽样法,选取中华护理学会2021年专科护士培训班学员作为试验组,2020年专科护士培训班学员作为对照组,两组学员涉及31个省(区、市)的3 300所医院。试验组采取同质化培训管理方案,对照组采取常规培训管理方案,比较两组的培训效果及学员满意度。结果 试验组培训人数为6 012名,对照组为4 619名。试验组理论考核成绩为(84.14±5.12)分,对照组为(79.66±8.36)分,两组比较,差异具有统计学意义(t=-32.133,P<0.001);试验组操作考核成绩为(94.24±3.58)分,对照组为(90.70±5.21)分,两组比较,差异具有统计学意义(t=-39.637,P<0.001)。试验组理论培训满意度调查问卷和临床实践满意度调查问卷总分为(75.00±1.38)和(72.53±0.92)分,均高于对照组(P<0.001)。结论 实施同质化管理能够有效提高专科护士培训质量,提升学员满意度。严格落实同质化管理策略,对推动全国... 相似文献
36.
目的 对比Monaco系统4种通量平滑度(Fluence-smoothing,FS)等级在直肠癌术后调强适形放射治疗技术(Intensity-Modulated Radiation Therapy,IMRT)中的剂量学差异,为临床选择FS参数提供参考。方法 选取2020年入院的15例直肠癌术后病例,在相同优化条件下,分别设置FS为Off、Low、Medium 和High进行计划设计,采用SPSS 20.0软件对数据进行统计分析;比较4种FS下靶区及危及器官(Organs at risk,OARs)的剂量参数、子野数(Segments)、机器跳数(Monitor units,MUs)、剂量计算时间(Estimated total delivery time,ETDT)及γ通过率。结果 4种FS下,靶区及OARs的剂量参数均满足临床需求,且不同FS等级下剂量分布差异无统计学意义;由FS-Off至FS-High,Segments、MUs及ETDT分别平均减少了15.2%、11.8%、6.7%,γ通过率提高了1.6%。结论 4种FS下IMRT计划均能满足临床要求,综合考虑计划质量和执行效率,建议采用FS-High用于直肠癌术后调强适形放射治疗。 相似文献
37.
PurposeTo assess the planned dose, in vivo dosimetry, acute skin toxicity, pain, and distress using Thermoplastic Elastomer (TPE) bolus for postmastectomy radiotherapy (PMRT).Material and methodsThirty-two PMRT patients with TPE bolus (17 patients for 25 fractions, 15 patients for the first 20 fractions) were selected for the study. The acute skin toxicity, pain, and psychological distress were assessed from the first treatment week to the fourth week after the end of treatment. At the first treatment, the MOSFET was used in vivo dosimetry measurement.ResultsIn vivo dosimetry with the bolus, the dose deviation ranged from −6.22% to −1.56% for 5 points. The presence of grade 1 and 2 skin toxicity reached its peak (70.0% and 13.3%) in the sixth week. Two patients (6.6%) with 25 fractions bolus experienced moist desquamation in the fifth and seventh week, with pain score 2 and 3, and interruptions of 3 and 5 days, respectively. The incidence of pain score 1, 2, and 3 peaked in the fifth (33.3%), fourth (33.3%), and seventh (10.0%) week. No patients experienced grade 3 skin toxicity and severe pain. One patient had significant anxiety, and two patients had significant depression.ConclusionThe TPE bolus can accurately fit skin and improve the surface dose to more than 90%. Twenty fractions with TPE bolus had similar skin toxicity and pain to those without bolus and did not increase patients' distress and clinical workload, compared with the literature's data, which is an alternative to the 3D printing bolus for PMRT. 相似文献
38.
39.
【目的】 从不同维度探讨我国学术期刊同质化问题,为着力解决该问题提供改进路径与应对策略。 【方法】 借鉴扎根理论方法思想,使用Nvivo 12定性数据分析软件,围绕学术期刊同质化的表征与本质、危害与原因、内外部路径与策略等关键问题,对来自中国知网的59篇有效文献进行内容分析。 【结果】 目前学术期刊同质化问题研究比较浅散,主要采取思辨、解释和案例分析等方法,缺乏深入的探索性、实证性和评价性研究。 【结论】 深刻认识和着力解决学术期刊同质化问题,需要对学术期刊同质化的影响因素、形成机理、评价指标、测评方法以及品牌化经营策略等内容进行深入探讨。 相似文献
40.
目的 分析广西4地带绦虫分离株COX1序列, 了解亚洲绦虫在广西的分布。方法 对鹿寨、 融水、 田东、 三江等 4县现症病人进行驱虫, 收集绦虫成虫。绦虫成虫经反复洗涤后, 各取孕节一节, 研碎后提取基因组DNA; 同时设计特异性引物, PCR扩增各分离株COX1片段, 对扩增产物进行T?A克隆测序; 应用相关软件分析序列的同源性、 遗传距离, 同时构建系统发生树。同时, 从GenBank检索亚洲绦虫、 猪带绦虫和牛带绦虫COX1基因序列, 并与4地分离株基因序列进行比较。结果 广西4地5个带绦虫分离株的COX1碱基序列长度均为444 bp。鹿寨株与亚洲绦虫之间基因差异为5个位点(1.11%), 同源性为98.87%, 遗传距离为0.011, 其在邻接法和简约法构建的系统发生树中位于同一分枝。融水A株与猪带绦虫同源性达100%, B株与牛带绦虫和亚洲绦虫的同源性分别达98.20%和96.17%; 田东和三江分离株与猪带绦虫的同源性分别为99.55%和96.40%, 遗传距离分别为0.005和0.037; 鹿寨株与牛带绦虫的同源性达96.40%。结论 广西鹿寨县存在亚洲绦虫流行, 融水县存在牛带绦虫和猪带绦虫混合流行。 相似文献