Abnormal Action Potentials Associated with the Shaker Complex Locus of Drosophila

Intracellular recordings of action potentials were made from the cervical giant axon in Shaker (Sh) mutants and normal Drosophila. The mutants showed abnormally long delays in repolarization. The defect is not due to abnormal Ca2+ channels, because it persists in the presence of Co2+, a Ca2+-channel blocker. On the other hand, the K+-channel blocker 4-aminopyridine causes a similar effect in normal animals, suggesting that the Sh mutant may have abnormal K+ conductance. Gene-dosage analysis of Sh shows that the defect is not due to underproduction of an otherwise normal molecule; it may be due to an abnormal molecule produced by the mutated gene. Gel electrophoresis failed to detect an abnormal protein, suggesting that, if Sh codes for a nervous system protein, it is rare. Genetic analysis of the Sh locus indicates three regions. Mutations or chromosome breaks in the two flanking regions cause Sh mutant physiology; the central region shows a "haplolethal effect"--i.e., heterozygous females are lethal

Agreement of retinal nerve fiber layer color codes between Stratus and Cirrus OCT according to glaucoma severity

PURPOSE: We assessed the agreement of retinal nerve fiber layer (RNFL) color codes between Stratus and Cirrus optical coherence tomography (OCT) according to the glaucoma severity. METHODS: We analyzed 184 eyes from 144 subjects with glaucoma and 40 normal subjects. Glaucoma was categorized into three subgroups according to mean deviation of visual field. The agreement of RNFL color code according to the glaucoma severity was assessed using Cohen's kappa value. Red or yellow color codes were defined as abnormal results, while green or white were defined as normal. Disagreement frequency of abnormal color code displayed by 2 OCTs was evaluated. RESULTS: The agreement of RNFL color code was fair to good in all subgroups (κ 0.288-0.887) except for the nasal quadrant, 1 to 4, and the 9 o'clock sectors. In all severity groups, the frequency of disagreement was less than 10% for average, temporal, and inferior sectors. However, Stratus OCT displayed abnormal results, while Cirrus showed normal results for nasal sectors with considerable disagreement proportion (severe 22.5%, moderate 13.2%, and early 13.6%). The disagreement tended to be pronounced in severe glaucoma. On the other hand, Cirrus OCT displayed abnormal results, while Stratus showed normal results for superior sectors (severe 10.0%, moderate 10.5%, and early 15.2%). The frequency was higher in early glaucoma. CONCLUSIONS: Considerable color code disagreements were observed in nasal and superior sectors, and the proportion was different according to the glaucoma severity. Color codes of two OCTs could not be considered interchangeable.ope

Neural plasticity and development in the first two years of life: Evidence from cognitive and socioemotional domains of research.

Three models that can be used to investigate the effects of different environmental events on brain development and organization are explored. The insult model argues against brain plasticity, and the environmental model regards the brain as infinitely plastic. Our work is guided by the transactional model, which views brain development and organization as an interaction between (a) genetically coded programs for the formation and connectivity of brain structures and (b) environmental modifiers of these codes. Data are reported from our cognitive and socioemotional research studies that support the notion of plasticity during the first 2 years of life. From our work with normal developmental processes, we draw parallels to abnormal development and speculate how the transactional model can be used to explain abnormal brain organization and development

REAKSI INVESTOR PASAR MODAL PADA PENGUMUMAN PENGHAPUSAN KODE BROKER

The policy of removing the broker codes of securities companies on the Indonesia Stock Exchange (IDX) has occurred for the first time in the Indonesian capital market. This policy was expected to prevent investors from buying shares by following transactional activities carried out by brokers, because using the broker code of a securities company, it is possible to know which securities company buys or sells a particular stock. The aim of this research is to  analyze the differences in trading volume, trading frequency, and abnormal returns before and  after the removal of broker codes so that the IDX can find out the effectiveness of the removal of the broker codes of securities companies and to find out whether investors have knowledge or not in making decisions to invest in stocks. The non-probabilistic purposive sampling technique was used and 738 companies listed on the IDX were used as the research sample. This study used an event study approach and data were analyzed using the Wilcoxon Signed Ranks Test. The results show that there were differences in trading volume, trading frequency, and abnormal returns before and after the removal of broker codes. Based on these findings, the removal of broker codes is an event that has information content and investors are expected to be able to conduct a deeper analysis when investing in the capital market. Keywords: trading volume; trading frequency; abnormal returns; broker code removal. Peristiwa kebijakan penghapusan kode broker perusahaan sekuritas pada Bursa Efek Indonesia (BEI) adalah pertama kali terjadi di pasar modal Indonesia. Kebijakan tersebut diharapkan dapat mencegah perilaku ikut-ikutan investor dalam membeli saham dari aktivitas transaksi yang dilakukan oleh broker karena melalui kode broker perusahaan sekuritas dapat diketahui broker dari perusahaan sekuritas mana yang banyak membeli atau menjual saham tertentu. Tujuan riset ini adalah untuk menganalisis perbedaan volume perdagangan, frekuensi perdagangan, dan return tidak normal (abnormal return) sebelum dan sesudah penghapusan kode broker, sehingga BEI dapat mengetahui seberapa efektif penghapusan kode broker perusahaan sekuritas tersebut dan untuk mengetahui investor memiliki pengetahuan atau tidak dalam pengambilan keputusan untuk berinvestasi saham selama ini. Teknik pengambilan sampel yang dipergunakan adalah non-probabilistic sampling dengan jenis purposive sampling, dengan 738 perusahaan yang tercatat di BEI yang akan dipergunakan sebagai sampel penelitian. Riset ini menggunakan pendekatan event study dan data dianalisis menggunakan Wilcoxon Signed Ranks Test. Hasil analisis data menunjukkan adanya perbedaan volume perdagangan, frekuensi perdagangan, dan abnormal return sebelum dan sesudah penghapusan kode broker. Berdasar pada hal tersebut penghapusan kode broker merupakan peristiwa yang memiliki kandungan informasi dan investor diharapkan dapat melakukan analisis lebih dalam pada saat hendak berinvestasi pada pasar modal. Kata kunci:  volume perdagangan; frekuensi perdagangan; abnormal return; penghapusan kode broker

A comprehensive study of sparse codes on abnormality detection

Sparse representation has been applied successfully in abnormal event detection, in which the baseline is to learn a dictionary accompanied by sparse codes. While much emphasis is put on discriminative dictionary construction, there are no comparative studies of sparse codes regarding abnormality detection. We comprehensively study two types of sparse codes solutions - greedy algorithms and convex L1-norm solutions - and their impact on abnormality detection performance. We also propose our framework of combining sparse codes with different detection methods. Our comparative experiments are carried out from various angles to better understand the applicability of sparse codes, including computation time, reconstruction error, sparsity, detection accuracy, and their performance combining various detection methods. Experiments show that combining OMP codes with maximum coordinate detection could achieve state-of-the-art performance on the UCSD dataset [14].Comment: 7 page

Hydroelectric power plant management relying on neural networks and expert system integration

The use of Neural Networks (NN) is a novel approach that can help in taking decisions when integrated in a more general system, in particular with expert systems. In this paper, an architecture for the management of hydroelectric power plants is introduced. This relies on monitoring a large number of signals, representing the technical parameters of the real plant. The general architecture is composed of an Expert System and two NN modules: Acoustic Prediction (NNAP) and Predictive Maintenance (NNPM). The NNAP is based on Kohonen Learning Vector Quantization (LVQ) Networks in order to distinguish the sounds emitted by electricity-generating machine groups. The NNPM uses an ART-MAP to identify different situations from the plant state variables, in order to prevent future malfunctions. In addition, a special process to generate a complete training set has been designed for the ART-MAP module. This process has been developed to deal with the absence of data about abnormal plant situations, and is based on neural nets trained with the backpropagation algorithm.Publicad