A sociographic study of student groups

The present investigation is one of social groups and not of the individuals who make up the groups. The aim was to obtain information about a fairly large number of groups and to attempt to express differences between groups, in quantitative terms. The small, selective sample of students are of no interest as biohoms, or even as socii. The subject of the investigation is the groups which the students list. The students are of interest only as a background to the work - to make it clear that the sample of groups which has been collected is a very selective one. This was not the original intention. The investigation was originally intended to be a study of the nature of the social groups to which social science students belong, as related to their attitudes and personal relationships within the social science class. This was to have been divided into three sections: 1. The collection of information on the social groups. 2. The collection of information on the attitudes of the students and their personal relationships. 3. The correlation of the results. The questionnaire which was drawn up for section 1, was prepared with the second part of the investigation in mind. When, however, a preliminary analysis of the results of this questionnaire was made, it was seen that a great deal of information on the social groups had been collected. The suggestion was made by Professor Batson that it might be profitable to concentrate on the analysis of these results, rather than to proceed with the second part of the investigation

Road recognition using coarse-grained vehicular traces

With more and more vehicles equipped with GPS tracking devices, there is increasing interest in building and updating maps using vehicular GPS traces. Most existing approaches for building maps rely on position traces from highly accurate positioning devices, which are sampled at a high frequency, e.g., every second. Typically these traces are recorded by survey vehicles. Commodity GPS devices are much more widespread, but have lower accuracy. In addition, the sampling frequency is low (at around once per minute) in order to reduce communication cost. Building maps from coarse-grained vehicular GPS traces is challenging due to the inherent noise in commodity GPS devices and the shape complexity of urban roads. In this paper, we propose a novel algorithm for recognizing urban roads with coarsegrained GPS traces from probe vehicles moving in urban areas. The algorithm overcomes the challenges by pruning low quality GPS traces, clustering GPS traces by road segments, and applying shape-aware B-spline fitting. We have conducted empirical study with a real data set of GPS traces from 2,300 taxis in Shanghai, China. Evaluation results demonstrate that our algorithm provides wide coverage, a low rate of false positives, and high accuracy. When there are 2,000 taxis and the time window for trace collection is 1.5 hours, the coverage of arterial roads is 93% and the rate of false positives is 5%. The roads recognized by our algorithm are more accurate than the roads on OpenStreetMap, a popular map editing website using GPS traces and satellite imagery. © Copyright 2012 Hewlett-Packard Development Company, L.P

Expression of TDP-43 C-terminal Fragments in Vitro Recapitulates Pathological Features of TDP-43 Proteinopathies*S⃞

The disease protein in frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis (ALS) was identified recently as the TDP-43 (TAR DNA-binding protein 43), thereby providing a molecular link between these two disorders. In FTLD-U and ALS, TDP-43 is redistributed from its normal nuclear localization to form cytoplasmic insoluble aggregates. Moreover, pathological TDP-43 is abnormally ubiquitinated, hyperphosphorylated, and N-terminally cleaved to generate C-terminal fragments (CTFs). However, the specific cleavage site(s) and the biochemical properties as well as the functional consequences of pathological TDP-43 CTFs remained unknown. Here we have identified the specific cleavage site, Arg208, of a pathological TDP-43 CTF purified from FTLD-U brains and show that the expression of this and other TDP-43 CTFs in cultured cells recapitulates key features of TDP-43 proteinopathy. These include the formation of cytoplasmic aggregates that are ubiquitinated and abnormally phosphorylated at sites found in FTLD-U and ALS brain and spinal cord samples. Furthermore, we observed splicing abnormalities in a cell culture system expressing TDP-43 CTFs, and this is significant because the regulation of exon splicing is a known function of TDP-43. Thus, our results show that TDP-43 CTF expression recapitulates key biochemical features of pathological TDP-43 and support the hypothesis that the generation of TDP-43 CTFs is an important step in the pathogenesis of FTLD-U and ALS

Enrichment of C-Terminal Fragments in TAR DNA-Binding Protein-43 Cytoplasmic Inclusions in Brain but not in Spinal Cord of Frontotemporal Lobar Degeneration and Amyotrophic Lateral Sclerosis

TAR DNA-binding protein (TDP-43) has been recently described as a major pathological protein in both frontotemporal dementia with ubiquitin-positive inclusions (FTLD-U) and amyotrophic lateral sclerosis. However, little is known about the relative abundance and distribution of different pathological TDP-43 species, which include hyperphosphorylated, ubiquitinated, and N-terminally cleaved TDP-43. Here, we developed novel N-terminal (N-t) and C-terminal (C-t)-specific TDP-43 antibodies and performed biochemical and immunohistochemical studies to analyze cortical, hippocampal, and spinal cord tissue from frontotemporal dementia with ubiquitin-positive inclusions and amyotrophic lateral sclerosis cases. C-t-specific TDP-43 antibodies revealed similar abundance, morphology, and distribution of dystrophic neurites and neuronal cytoplasmic inclusions in cortex and hippocampus compared with previously described pan-TDP-43 antibodies. By contrast, N-t-specific TDP-43 antibodies only detected a small subset of these lesions. Biochemical studies confirmed the presence of C-t TDP-43 fragments but not extreme N-t fragments. Surprisingly, immunohistochemical analysis of inclusions in spinal cord motor neurons in both diseases showed that they are N-t and C-t positive. TDP-43 inclusions in Alzheimer’s disease brains also were examined, and similar enrichment in C-t TDP-43 fragments was observed in cortex and hippocampus. These results show that the composition of the inclusions in brain versus spinal cord tissues differ, with an increased representation of C-t TDP-43 fragments in cortical and hippocampal regions. Therefore, regionally different pathogenic processes may underlie the development of abnormal TDP-43 proteinopathies