Modulated Hebb-Oja learning rule--a method for principal subspace analysis.

PubMed

Jankovic, Marko V; Ogawa, Hidemitsu

2006-03-01

This paper presents analysis of the recently proposed modulated Hebb-Oja (MHO) method that performs linear mapping to a lower-dimensional subspace. Principal component subspace is the method that will be analyzed. Comparing to some other well-known methods for yielding principal component subspace (e.g., Oja's Subspace Learning Algorithm), the proposed method has one feature that could be seen as desirable from the biological point of view--synaptic efficacy learning rule does not need the explicit information about the value of the other efficacies to make individual efficacy modification. Also, the simplicity of the "neural circuits" that perform global computations and a fact that their number does not depend on the number of input and output neurons, could be seen as good features of the proposed method.

Simple modification of Oja rule limits L1-norm of weight vector and leads to sparse connectivity.

PubMed

Aparin, Vladimir

2012-03-01

This letter describes a simple modification of the Oja learning rule, which asymptotically constrains the L1-norm of an input weight vector instead of the L2-norm as in the original rule. This constraining is local as opposed to commonly used instant normalizations, which require the knowledge of all input weights of a neuron to update each one of them individually. The proposed rule converges to a weight vector that is sparser (has more zero weights) than the vector learned by the original Oja rule with or without the zero bound, which could explain the developmental synaptic pruning.

Detection of Metallothionein in Javanese Medaka (Oryzias javanicus), Using a scFv-Immobilized Protein Chip

PubMed Central

Lee, Euiyeon; Jeon, Hyunjin; Kang, Chungwon; Woo, Seonock; Yum, Seungshic; Kwon, Youngeun

2018-01-01

Environmental pollution by various industrial chemicals and biological agents poses serious risks to human health. Especially, marine contamination by potentially toxic elements (PTEs) has become a global concern in recent years. Many efforts have been undertaken to monitor the PTE contamination of the aquatic environment. However, there are few approaches available to assess the PTE exposure of aquatic organisms. In this research, we developed a strategy to evaluate the heavy metal exposure of marine organisms, by measuring the expression levels of metallothionein protein derived from Oryzias javanicus (OjaMT). OjaMT is a biomarker of heavy metal exposure because the expression level increases upon heavy metal exposure. The developed assay is based on a real-time, label-free surface plasmon resonance (SPR) measurement. Anti-OjaMT antibody and anti-OjaMT single-chain fragment of variable region (scFv) were used as detection probes. Two types of SPR sensor chips were fabricated, by immobilizing antibody or Cys3-tagged scFv (scFv-Cys3) in a controlled orientation and were tested for in situ label-free OjaMT detection. Compared to the antibody-presenting sensor chips, the scFv-presenting sensor chips showed improved performance, displaying enhanced sensitivity and enabling semi-quantitative detection. The portable SPR system combined with scFv-immobilized sensor chips is expected to provide an excellent point-of-care testing system that can monitor target biomarkers in real time. PMID:29614840

All Prime Contract Awards by State or Country, Place, and Contractor, FY83, Part 1 (Argentina-Goodyear, Arizona).

DTIC Science & Technology

1983-01-01

C Z 5 2 2 5110 000 69 HAND TOOLS EDGED NONPOWERED 7 9 3 5 L 06 1 B 4 1 0 100 WAESCHEREI KRAUSE GERMANY 088616 0000 GY I L OJA37 2913 DAJA37-82-00210 B...0 27 WOLFGANG PRAYON GERMANY 090010 0000 GY I D OJA37 0369 DAJA37-82-DO261 B C 2 5 3 2 V212 000 S MOTOR PASSENGER SERVICE 7 9 4 5 L 06 1 B J 1 J 34

Earth observations taken during STS-83 mission

NASA Image and Video Library

2016-08-24

STS083-749-084 (4-8 April 1997) --- Laguna Oja De Liebre, Baja, gray whale breeding ground Laguna Oja De Liebre, Baja (Scammons Lagoon) is located on the west coast in the plains of the central Baja. This lagoon and others like it along the Baja coast are used for breeding grounds for the gray whale. One group of gray whales inhabits the Sea of Okhotsk in summer, migrating south in winter then breed off southern Korea. The other summers in the Bering and Chukchi seas and travels south to winter breeding grounds along the coast of Baja California. The gray whale was hunted almost to extinction by 1925 but was placed under complete international protection and since the 1940s has increased in numbers. The white grids seen in the photo are commercial salt ponds.

Global Realities: Celebrating Our Differences, Honoring Our Connections.

ERIC Educational Resources Information Center

Walz, Garry R., Ed.; Knowdell, Richard L., Ed.

This publication contains papers based on program presentations from the 2003 International Career Development Conference. Chapters include: (1) How to Turn Your Passion into a Profit (S. Abbott); (2) Harnessing the Power of Career Transition Groups (M. Adoradio and A. Oja); (3) All the Worlds a Stage Using Theatre in Career Counseling (P.…

Effects of Dose Frequency of Early Communication Intervention in Young Children with and without Down Syndrome

ERIC Educational Resources Information Center

Yoder, Paul; Woynaroski, Tiffany; Fey, Marc; Warren, Steven

2014-01-01

Children with intellectual disability were randomly assigned to receive Milieu Communication Teaching (MCT) at one 1-hr session per week (low dose frequency, LDF) or five 1-hr sessions per week (high dose frequency, HDF) over 9 months (Fey, Yoder, Warren, & Bredin-Oja, 2013. Non-Down syndrome (NDS) and Down syndrome (DS) subgroups were matched…

Surface Observation Climatic Summaries (SOCS) for March AFB, California

DTIC Science & Technology

1989-11-01

ANl , IL U’T4MMAkIZEU AS FOLLOWS: BY EIGAT 3 4OjA STANDARD) TIME PEK~ l . * LALII MONfl (AL, (LAP,-. !3NE) *BY MONTH (ALL TEARS AWL’ .lL - ~k 4-b;NfT...09 11 i .. 4t MS U 1 6034 2610 42 1095812-14. 75.3 13.679 10959 0 0 8227 4224 1409 10959 15-17’ 73.8 13.216 10957 0 0 7928 3897 96i 10957 18-20 ,,.8

M-X Environmental Technical Report. Socioeconomic Impact Estimates for New Mexico ROI Counties. Detailed Tables.

DTIC Science & Technology

1980-12-22

I - I l r 0(nMr P I I 0 i I ’. !s.IV 0 nI W I I I - I W I 4’ l PO a.4 C’) In I CV a M 1I 00 rAVV - V) oj~A" .0. i 1I I10...W %n D a ta E n te re d) R E ADI N S T R U C T I O N S REPORT DOCUMENTATION PAGE READ INSTRUCTIONS BEFORE COMPLETING FORM 1. REPORT NUMBER 12. GOVT...report relate to the following areas: (continued on reverse) DD , oANF 1473 EDITION OF I NOV 6S IS OBSOLETE

Earth observations taken from Space Shuttle Columbia during STS-93 mission

NASA Image and Video Library

1999-07-23

STS093-704-087 (23-27 July 1999) --- This low angle, early morning shot over Chile was photographed from the Earth-orbiting Space Shuttle Columbia during the STS-93 mission. In the words of one of the scientists studying the STS-93 Earth imagery, Laguna Verde, in the Atacama Province of Chile (near the Argentine border), lies like a turquoise jewel among the stark black and white snow covered volcanic peaks of the High Andes. The ambient elevation in this part of the Andes is 16,000 feet (4,877 meters) with the highest local peak, Nevada Ojas de Salado (just to the right of the lake), reaching to 23,240 feet. (7084 meters.)

Excitement and synchronization of small-world neuronal networks with short-term synaptic plasticity.

PubMed

Han, Fang; Wiercigroch, Marian; Fang, Jian-An; Wang, Zhijie

2011-10-01

Excitement and synchronization of electrically and chemically coupled Newman-Watts (NW) small-world neuronal networks with a short-term synaptic plasticity described by a modified Oja learning rule are investigated. For each type of neuronal network, the variation properties of synaptic weights are examined first. Then the effects of the learning rate, the coupling strength and the shortcut-adding probability on excitement and synchronization of the neuronal network are studied. It is shown that the synaptic learning suppresses the over-excitement, helps synchronization for the electrically coupled network but impairs synchronization for the chemically coupled one. Both the introduction of shortcuts and the increase of the coupling strength improve synchronization and they are helpful in increasing the excitement for the chemically coupled network, but have little effect on the excitement of the electrically coupled one.

A new modulated Hebbian learning rule--biologically plausible method for local computation of a principal subspace.

PubMed

Jankovic, Marko; Ogawa, Hidemitsu

2003-08-01

This paper presents one possible implementation of a transformation that performs linear mapping to a lower-dimensional subspace. Principal component subspace will be the one that will be analyzed. Idea implemented in this paper represents generalization of the recently proposed infinity OH neural method for principal component extraction. The calculations in the newly proposed method are performed locally--a feature which is usually considered as desirable from the biological point of view. Comparing to some other wellknown methods, proposed synaptic efficacy learning rule requires less information about the value of the other efficacies to make single efficacy modification. Synaptic efficacies are modified by implementation of Modulated Hebb-type (MH) learning rule. Slightly modified MH algorithm named Modulated Hebb Oja (MHO) algorithm, will be also introduced. Structural similarity of the proposed network with part of the retinal circuit will be presented, too.

Holloman AFB, New Mexico. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F.

DTIC Science & Technology

1982-04-12

A RC ..... sl6 3i4 ~ N0 A.o 0 o2 *I A3 05 .7 0 to TRACE A 5S :S TRAC .29 .0.0 *2.. *,.j st16 &TRC T ACt la S4 :01 o Ŕ TRAC risAc *4 ?P.TAC *I .0 .02...2l 046 t.2 145 .14 TRACE TRACI T*A TRI 004....~ 60 A001. sOJa .. , 46 .31 .04 .01 6 at .0 .2 .10 47 1_ 1_ - -A .121 __ 48 1.2 .61 .0 TRAC 2.9 l.9 al...r - sea--vu 6s 23.6 *7.6 20 1 9 26 1.9 7 02__1 wo 10mS 0 .5 02U*1*7 9 w 91 "m,. om .4FVC%. LA ~im wm ul 19 292 Ze* ~ U -A- GLiCBAL CLIMATOLOGY

Noch ein "Geheimnis des Jazz": Saying "Oja" to Afro-German Studies.

ERIC Educational Resources Information Center

Divers, Greg

1995-01-01

Introduces classroom materials with which African American students who are studying German can identify. The article shows that contemporary German poetry and the work of African American poets in German translation offer many possibilities for exercises that speak directly to African American students at all levels. (25 references) (Author/CK)

Independet Component Analyses of Ground-based Exoplanetary Transits

NASA Astrophysics Data System (ADS)

Silva Martins-Filho, Walter; Griffith, Caitlin Ann; Pearson, Kyle; Waldmann, Ingo; Biddle, Lauren; Zellem, Robert Thomas; Alvarez-Candal, Alvaro

2016-10-01

Most observations of exoplanetary atmospheres are conducted when a "Hot Jupiter" exoplanet transits in front of its host star. These Jovian-sized planets have small orbital periods, on the order of days, and therefore a short transit time, making them more ameanable to observations. Measurements of Hot Jupiter transits must achieve a 10-4 level of accuracy in the flux to determine the spectral modulations of the exoplanetary atmosphere. In order to accomplish this level of precision, we need to extract systematic errors, and, for ground-based measurements, the effects of Earth's atmosphere, from the signal due to the exoplanet, which is several orders of magnitudes smaller. Currently, the effects of the terrestrial atmosphere and the some of the time-dependent systematic errors are treated by dividing the host star by a reference star at each wavelength and time step of the transit. More recently, Independent Component Analyses (ICA) have been used to remove systematic effects from the raw data of space-based observations (Waldmann 2014,2012; Morello et al.,2015,2016). ICA is a statistical method born from the ideas of the blind-source separation studies, which can be used to de-trend several independent source signals of a data set (Hyvarinen and Oja, 2000). One strength of this method is that it requires no additional prior knowledge of the system. Here, we present a study of the application of ICA to ground-based transit observations of extrasolar planets, which are affected by Earth's atmosphere. We analyze photometric data of two extrasolar planets, WASP-1b and GJ3470b, recorded by the 61" Kuiper Telescope at Stewart Observatory using the Harris B and U filters. The presentation will compare the light curve depths and their dispersions as derived from the ICA analysis to those derived by analyses that ratio of the host star to nearby reference stars.References: Waldmann, I.P. 2012 ApJ, 747, 12, Waldamann, I. P. 2014 ApJ, 780, 23; Morello G. 2015 ApJ, 806

A critical review of concept of aging in Ayurveda

PubMed Central

Devi, Durgawati; Srivastava, Rajeev; Dwivedi, B. K.

2010-01-01

Ayurveda has a holistic approach toward all the miseries of man and aging is one of these. It is classified as one of the natural and Yapya (palliative) diseases. It is the process of becoming old and decaying. As age advances, several changes take place in the body, in the external appearance, in the condition of Dosha, Dhatu, Mala, Agni, Oja, and so on, as well as in the mental and cognitive functions. Elderly people are susceptible to several chronic diseases also. The problems of the elderly are becoming a matter of great concern as increased life expectancy due to better medical services and improved technology is resulting in an increasing population of the aged. By the year 2020, the World will have more than one billion people aged 60 and over, and more than two-thirds of them will be living in the developing countries. A major concern related to the rapid increase in the population of the aged is that there will be an increase in the prevalence of chronic diseases and disabilities, both being conditions that tend to accompany the aging process. This burden is increasing day by day. In the Ayurvedic texts, a comprehensive description has been given of aging. The aim of this conceptual article is to compile and re-evaluate the various principles related to different aspects of aging. PMID:22048551

Algorithms for accelerated convergence of adaptive PCA.

PubMed

Chatterjee, C; Kang, Z; Roychowdhury, V P

2000-01-01

We derive and discuss new adaptive algorithms for principal component analysis (PCA) that are shown to converge faster than the traditional PCA algorithms due to Oja, Sanger, and Xu. It is well known that traditional PCA algorithms that are derived by using gradient descent on an objective function are slow to converge. Furthermore, the convergence of these algorithms depends on appropriate choices of the gain sequences. Since online applications demand faster convergence and an automatic selection of gains, we present new adaptive algorithms to solve these problems. We first present an unconstrained objective function, which can be minimized to obtain the principal components. We derive adaptive algorithms from this objective function by using: 1) gradient descent; 2) steepest descent; 3) conjugate direction; and 4) Newton-Raphson methods. Although gradient descent produces Xu's LMSER algorithm, the steepest descent, conjugate direction, and Newton-Raphson methods produce new adaptive algorithms for PCA. We also provide a discussion on the landscape of the objective function, and present a global convergence proof of the adaptive gradient descent PCA algorithm using stochastic approximation theory. Extensive experiments with stationary and nonstationary multidimensional Gaussian sequences show faster convergence of the new algorithms over the traditional gradient descent methods.We also compare the steepest descent adaptive algorithm with state-of-the-art methods on stationary and nonstationary sequences.

Conceptual analysis of diabetic retinopathy in Ayurveda.

PubMed

Sahoo, Prasanta Kumar; Fiaz, Shamsa

Inclusion of Prameha among the eight major disorders in Charaka Samhita shows the importance of the disease given by ancient seers. The risk of development of blindness in diabetics increases by 20-25 times as compared to the normal population. High prevalence rate of Diabetic Retinopathy (34.6%), proliferative diabetic retinopathy (7%), diabetic macular edema (6.8%), and Vision threatening Diabetic retinopathy (10.2%) in diabetics was great concerns which led to search and analyze the disease process on the basis of modern pathogenesis and different Timirvyadhi mentioned in Ayurvedic authoritative texts. Thus the present study endeavors to discuss the similarities and differences among the various components of Prameha/Madhumehajanya Timir with Diabetic retinopathy and its stages. To establish a probable etiopathogenesis of the disease from Ayurveda prospective, all the important literature of both modern medicine and Ayurveda along with online sources were searched and analyzed. All the three dosha along with Raktadosha and Saptadhatu with four internal Dristipatals of eye are affected in Madhumehajanya timir in different stages of the disease. Avarana and Dhatu kshaya too have important role in development of diabetic retinopathy due to prolonged and uncontrolled hyperglycemia. Agnimandya related Ama formation has a role in pathology of diabetic retinopathy which is quite similar to oxidative theory of diabetic retinopathy explained in modern pathology. Urdhwaga raktapitta, Ojas kshaya, Raktavritta vata, and Pranavritta vyana are other causes in development of diabetic retinopathy. Copyright © 2017 Transdisciplinary University, Bangalore and World Ayurveda Foundation. Published by Elsevier B.V. All rights reserved.

Independent Component Analysis applied to Ground-based observations

NASA Astrophysics Data System (ADS)

Martins-Filho, Walter; Griffith, Caitlin; Pearson, Kyle; Waldmann, Ingo; Alvarez-Candal, Alvaro; Zellem, Robert Thomas

2018-01-01

Transit measurements of Jovian-sized exoplanetary atmospheres allow one to study the composition of exoplanets, largely independent of the planet’s temperature profile. However, measurements of hot-Jupiter transits must archive a level of accuracy in the flux to determine the spectral modulation of the exoplanetary atmosphere. To accomplish this level of precision, we need to extract systematic errors, and, for ground-based measurements, the effects of Earth’s atmosphere, from signal due to the exoplanet, which is several orders of magnitude smaller. The effects of the terrestrial atmosphere and some of the time-dependent systematic errors of ground-based transit measurements are treated mainly by dividing the host star by a reference star at each wavelength and time step of the transit. Recently, Independent Component Analysis (ICA) have been used to remove systematics effects from the raw data of space-based observations (Waldmann, 2014, 2012; Morello et al., 2016, 2015). ICA is a statistical method born from the ideas of the blind-source separations studies, which can be used to de-trend several independent source signals of a data set (Hyvarinen and Oja, 2000). This technique requires no additional prior knowledge of the data set. In addition, this technique has the advantage of requiring no reference star. Here we apply the ICA to ground-based photometry of the exoplanet XO-2b recorded by the 61” Kuiper Telescope and compare the results of the ICA to those of a previous analysis from Zellem et al. (2015), which does not use ICA. We also simulate the effects of various conditions (concerning the systematic errors, noise and the stability of object on the detector) to determine the conditions under which an ICA can be used with high precision to extract the light curve of exoplanetary photometry measurements

Action spectra of photosystems II and I and quantum yield of photosynthesis in leaves in State 1.

PubMed

Laisk, Agu; Oja, Vello; Eichelmann, Hillar; Dall'Osto, Luca

2014-02-01

The spectral global quantum yield (YII, electrons/photons absorbed) of photosystem II (PSII) was measured in sunflower leaves in State 1 using monochromatic light. The global quantum yield of PSI (YI) was measured using low-intensity monochromatic light flashes and the associated transmittance change at 810nm. The 810-nm signal change was calibrated based on the number of electrons generated by PSII during the flash (4·O2 evolution) which arrived at the PSI donor side after a delay of 2ms. The intrinsic quantum yield of PSI (yI, electrons per photon absorbed by PSI) was measured at 712nm, where photon absorption by PSII was small. The results were used to resolve the individual spectra of the excitation partitioning coefficients between PSI (aI) and PSII (aII) in leaves. For comparison, pigment-protein complexes for PSII and PSI were isolated, separated by sucrose density ultracentrifugation, and their optical density was measured. A good correlation was obtained for the spectral excitation partitioning coefficients measured by these different methods. The intrinsic yield of PSI was high (yI=0.88), but it absorbed only about 1/3 of quanta; consequently, about 2/3 of quanta were absorbed by PSII, but processed with the low intrinsic yield yII=0.63. In PSII, the quantum yield of charge separation was 0.89 as detected by variable fluorescence Fv/Fm, but 29% of separated charges recombined (Laisk A, Eichelmann H and Oja V, Photosynth. Res. 113, 145-155). At wavelengths less than 580nm about 30% of excitation is absorbed by pigments poorly connected to either photosystem, most likely carotenoids bound in pigment-protein complexes. Copyright © 2013 Elsevier B.V. All rights reserved.