Statistical analysis of gait patterns of persons with cerebral palsy

Patients at Boston's Children's Hospital diagnosed as having cerebral palsy were filmed walking. These films were digitized and translated into measurements associated with leg motion. In this paper we use the gait measurements of 128 such patients to illustrate that the kth nearest neighbour clustering procedure results in a gait typology for patients with cerebral palsy. The procedure identifies four subpopulations from the sample data; the membership of a patient within this typology is mostly determined by the patient's motor control. The developed typology differs from the present diagnostic system which classifies a cerebral palsy patient as either quadriplegic, diaplegic or hemiplegic.     

Clustering of autoimmune disease in parents of siblings from the Type 1 diabetes Warren repository.

AIMS: Autoimmune disorders co-exist in the same individuals and in families, implying a shared aetiology. The aim of this study was to compare the prevalence of the common autoimmune diseases in the parents of siblings from the Type 1 diabetes Warren repository with the general population. METHODS: Between 1989 and 1996, 505 British families with at least two siblings affected by Type 1 diabetes were recruited. Clinical information was collected regarding the presence of autoimmune disease in the parents and the prevalence of disease in the parents was compared with that expected in the general population. RESULTS: The prevalence of autoimmune disease in the parents was significantly higher in the repository compared with that expected in the general population [P-value = 1.98 x 10(-5) (female), P-value = 1.1 x 10(-8) (male)]. Type 1 diabetes was recorded in 63/1010 (6.2%) parents with a marked paternal preponderance (9.5 vs. 3%P = 0.002). Other autoimmune diseases affected 27% of parents with diabetes and 13.2% of parents without diabetes (P < 0.01). CONCLUSION: These data confirm the importance of family history as a significant risk factor for the development of Type 1 diabetes and support the hypothesis that the common autoimmune diseases share at least some aetiological mechanisms.     

基于实验均方误差F值的基因表达数据最佳聚类评判方法研究

目的 近年来产生了一些用于分析基因表达数据的聚类算法，却很少有关于评价聚类算法方法的研究。本研究的目的是尝试建立一个定量的评价基因表达数据聚类结果的方法。方法 本研究提供了一个系统的评价聚类结果的方法，利用我们提出的实验均方误差F值对几个常见的聚类算法进行比较。结果 利用F值对类质量的评价和利用已有的生物学知识对类进行分析的结果一致。结论 实验均方误差F值可以定量地评判用于基因表达数据的聚类算法。     

Short utterance recognition using a network with minimum training

A feedforward network is used to recognize short, digitized, isolated utterances. A high, multispeaker recognition rate is achieved with a small vocabulary with a single training utterance. This approach makes use of the pattern recognition property of the network architecture to classify different temporal patterns in the multidimensional feature space. The network recognizes the utterances without the need of segmentation, phoneme identification, or time alignment. We train the network with four words spoken by one single speaker. The network is then able to recognize 20 tokens spoken by 5 other speakers. We repeat the above training and testing procedure using a different speaker's utterances for training each time. The overall accuracy is 97.5%. We compare this approach to the traditional dynamic programming (DP) approach, and find that DP with slope constraints of 0 and 1 achieve 98.5% and 85% accuracies respectively. Finally we validate out statistics by training and testing the network of a four-word subset of the Texas Instruments (Tl) isolated word database. The accuracy with this vocabulary exceeds 96%. By doubling the size of the training set, the accuracy is raised to 98%. Using a suitable threshold, we are able to raise the accuracy of one network from 87% to 98.5%. Thresholding applied to all networks would then raise the overall accuracy to well over 99%.

This technique is especially promising because of the low overhead and computational requirements, which make it suitable for a low cost, portable, command recognition type of application.     

Unsupervised fuzzy clustering analysis supports behavioral cutoff criteria in an animal model of posttraumatic stress disorder.

BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies.     

Distribution of the largest neuron in mouse caudate-putamen nucleus: Its position in large-cell — Medium-cell clusters

Summary The position of the largest striatal neuron within territories delimited by medium-sized clustered neurons was charted in Nissl-stained sections through the mouse caudate-putamen nucleus. Medium-sized neuron somata occur in close proximity to this large cell at some point in the anteroposterior, mediolateral or dorsoventral extent of its soma. The size of the network of medium-sized neurons associated with the large cell may vary from two to 15 neurons. Even when this network is extensive, the large neuron is never completely surrounded. Most often, this cell also borders a fascicle of internal capsule fibers, and the entire cellular island may be aligned either parallel to or perpendicular to the orientation of these fibers. These findings suggest the hypothesis that cellular territories in the caudate-putamen nucleus have a very specific orientation in three dimensional space.     

Clustering of allergenic pollen on the basis of skin responses of atopic patients by matrix analysis

The responses of 148 atopic patients to some 43 different extracts of allergenic pollen were tested by prick tests. The measure of dissimilarity was introduced and calculated for all pairs of allergens. The investigated allergens were clustered into groups, according to their unbiased greatest similarity, by a matrix-structuring method. Results indicate that subgroups of allergens can be distinguished even within groups of closely related pollen allergens that were believed to be fully cross-reactive. A few cases are demonstrated for various varieties of olives, pecans, date palms, and turf grasses and for some wild chenopods and amaranths. The usefulness of the suggested solution for allergy research and for clinical practice is discussed.     

2008—2018年济南市饮用水健康风险时空特征研究

目的 为掌握济南市饮用水水质卫生状况,识别可能存在健康风险的有害物质,为今后安全供水提供技术依据。方法 收集济南市2008—2018年生活饮用水监测数据,利用美国环保署风险评估四步法,分析健康风险时间、空间分布情况。结果 氟化物、硝酸盐氮少量水样非致癌风险超过1.0,农村水样风险高于城市。砷、铅检出较少,但检出限高于风险限,可能存在未分辨风险。三氯甲烷城市水样每年有12.5%或25%的比例致癌风险超过10-6,农村水样只在2017年有5%超过10-6。结论 济南市2008—2018年饮用水健康风险整体较低。但砷检出限较高,目前检测技术难以定量分辨砷致癌风险。需开展持续监测和定期评估,及时发现潜在问题。需要增加农村自来水饮用宣传,消除地方性饮水型高氟。     

Aggregation of childhood leukemia in geographic areas of Greece)

A total of 872 children aged up to 14 years, who were diagnosed withleukemia in Greece during the decade 1980-89, were allocated by place ofresidence to the 601 administrative districts of the country. Evaluation ofspatial clustering was done using the Potthoff-Whittinghill method, whichvalidly assesses heterogeneity of leukemia risk among districts with variableexpected numbers of cases. There was highly significant evidence for spatialclustering occurring particularly among children living in urban and, to alesser extent, semi-urban areas. The evidence was stronger for childrenyounger than 10 years old, applied also to children in different five-yearage groups, and persisted when cases of acute lymphoblastic leukemia wereanalyzed separately. These findings provide support to the hypothesis thatlocalized environmental exposures could contribute to the etiology ofchildhood leukemia, but they cannot distinguish between exposures of physicalor chemical nature, nor can they exclude socially conditioned patterns ofexposure to infectious agents.     

Geographic Clustering Patterns in Mortality from Biliary Tract Cancer in Japan

We calculated the standardized mortality ratios (SMRs) of biliary tract cancer (BTC) in Japan from 1981 to 1990 and statistically analyzed the results according to 333 Secondary Areas of Medical Care, as well as sex and subsite [gallbladder cancer (GBC) and extrahepatic bile duct cancer (BDC)], in order to examine geographic clustering patterns of BTC. In GBC in both sexes, the Secondary Areas of Medical Care with high SMRs were clustered in the eastern part of Japan. In BDC in both sexes, the Areas with high SMRs were clustered between the northern and eastern parts of Japan. In comparison with GBC, this clustering favored the northern part of Japan. In males, the clustering pattern in mortality from BTC was mainly due to the occurrence of BDC. In females, the clustering pattern in mortality from BTC reflected that of GBC. The clustering of BTC, especially GBC, seems to be related to the distribution of plains, basins, and rivers.