301 results on '"R, OKA"'
Search Results
2. Deep-learning reconstruction to improve image quality of myocardial dynamic CT perfusion: comparison with hybrid iterative reconstruction
- Author
-
M. Takafuji, K. Kitagawa, S. Mizutani, R. Oka, R. Kisou, S. Sakaguchi, K. Ichikawa, D. Izumi, and H. Sakuma
- Subjects
Perfusion ,Deep Learning ,Image Processing, Computer-Assisted ,Humans ,Radiographic Image Interpretation, Computer-Assisted ,Radiology, Nuclear Medicine and imaging ,General Medicine ,Radiation Dosage ,Tomography, X-Ray Computed ,Algorithms - Published
- 2022
3. Arab American Adolescents’ Responses to Perceived Discrimination: A Phenomenological Study
- Author
-
Dorinda J. Carter Andrews, Danielle Balaghi, and Evelyn R. Oka
- Subjects
Psychiatry and Mental health ,Health (social science) ,Religious studies ,Arab americans ,Psychology ,Developmental psychology - Abstract
Racial discrimination is on the rise in the United States. Arab American Muslims is one group that has experienced an increase in perceived racial discrimination. Even less is known about Arab American Muslim Adolescents experiences of coping when faced with racial discrimination. This study aims to highlight the lived experiences of Arab American adolescents’ perceived racial discrimination as it relates to their coping experiences. There were 10 (female=5; male=5) Arab American youth ages 13-17 and identified as Muslim. Participants were recruited using purposive sampling. Using a phenomenological approach, data were collected using semi-structured individual interviews and online journals. Validity was assessed via member checks and triangulation of data using multiple participants and sources. The data were analyzed using interpretive phenomenological analysis, guided by Risk and Resilience theory and Critical Race Theory. Results highlighted three positive and three negative ways participants experienced coping to perceived racial discrimination. Implications of this study can aid psychologists in promoting positive responses to racial discrimination while also helping students recognize negative responses. Understanding the way an adolescent responds provides better insight into their psychological well-being.
- Published
- 2021
- Full Text
- View/download PDF
4. Experiences of discrimination among Black middle school adolescents: A qualitative study
- Author
-
Chimereodo Okoroji and Evelyn R. Oka
- Subjects
Schools ,Adolescent ,Critical race theory ,education ,Context (language use) ,PsycINFO ,Education ,Developmental psychology ,Developmental and Educational Psychology ,Humans ,Psychology ,Students ,Phenomenology (psychology) ,Qualitative Research ,Qualitative research - Abstract
Discrimination is a common experience among racially and ethnically minoritized (REM) youth and often results in negative health and psychological outcomes. However, few studies provide adolescents with opportunities to directly share their discriminatory experiences, especially within the school context. Using a critical race theory framework and phenomenological approach, the present study explored how Black middle school students experienced and responded to discrimination in school settings. Findings revealed that youth experienced both direct and vicarious discrimination at school from multiple sources. Additionally, their responses indicated developmental and adaptive challenges, as well as a nuanced understanding of discrimination in their daily lives. Implications regarding educators' roles in affirming and supporting Black students' experiences are discussed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
- Published
- 2021
5. Semi-Automatic Classification of Prostate Cancer from Multi-Parametric MR Imaging Using Novel Image Sequences and 3D Convolutional Neural Networks
- Author
-
B, Li, primary, R, Oka, additional, P, Xuan, additional, Y, Yoshimura, additional, and T, Nakaguchi, additional
- Published
- 2021
- Full Text
- View/download PDF
6. The relationship between polypharmacy and recovery of activities of daily living among convalescent stroke patients: A propensity score-matched analysis
- Author
-
Manabu Toyoshima, R. Oka, Eiji Kose, S. Okazoe, Hiroyuki Hayashi, and Y. Shiratsuchi
- Subjects
Polypharmacy ,Rehabilitation hospital ,medicine.medical_specialty ,Rehabilitation ,Activities of daily living ,business.industry ,medicine.medical_treatment ,Retrospective cohort study ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Propensity score matching ,medicine ,Physical therapy ,030212 general & internal medicine ,Geriatrics and Gerontology ,Medical prescription ,business ,Gerontology ,Stroke ,030217 neurology & neurosurgery - Abstract
Introduction Polypharmacy induces side effects or drug interaction for elderly patients. Whether polypharmacy negatively affects stroke rehabilitation of patients is unclear in Japan. The aim of this study was to assess the relationship between polypharmacy and recovery of daily activity among convalescent stroke patients. Methods In this retrospective cohort study, we screened 719 stroke patients who were admitted to and discharged from the Sagami Rehabilitation Hospital or the Tsurumaki Onsen Hospital between April 2012 and July 2014 in Kanagawa, Japan. Among 719 patients screened, 509 were excluded because of propensity score matching. The primary outcome was Functional Independence Measure-Motor (FIM-M) effectiveness, and participants were divided according to FIM-M effective scores into the following two groups: non-improvement (105 patients) or improvement of FIM-M effectiveness (105 patients). Results Risk factors associated with non-improvement of FIM-M effectiveness included epilepsy and number of drugs used upon admission. FIM-M effectiveness in the patients in whom five or more drugs were used upon admission was significantly lower than in those in whom one drug was used. Through this finding, we defined the use of five or more drugs as polypharmacy. Drugs with significant differences regarding polypharmacy included antihypertensive and antidiabetic drugs. Conclusions These findings suggested that polypharmacy negatively affects stroke rehabilitation outcomes. Thus, pharmacists should make attempts to respond to individual patient outcomes to optimize prescriptions, which may minimize the brunt of polypharmacy on patient outcomes.
- Published
- 2017
- Full Text
- View/download PDF
7. Comparison of Abnormal Prostate MRI and Histopathology of Prostatic Biopsy after Intravesical BCG Therapy for Non-Muscle Invasive Bladder Cancer
- Author
-
T, Mori, primary, N, Kamiya, additional, N, Hiruta, additional, S, Kato, additional, T, Somoto, additional, R, Oka, additional, T, Utsumi, additional, T, Endo, additional, M, Yano, additional, N, Kitamura, additional, T, Inaoka, additional, and H, Suzuki, additional
- Published
- 2020
- Full Text
- View/download PDF
8. Parent–Child Conflict, Acculturation Gap, Acculturative Stress, and Behavior Problems in Arab American Adolescents
- Author
-
Anisa N. Goforth, Andy V. Pham, and Evelyn R. Oka
- Subjects
Cultural Studies ,Mediation (statistics) ,Social Psychology ,Anthropology ,Cultural orientation ,Arab americans ,Parent/child conflict ,Psychology ,Social psychology ,Acculturation ,Developmental psychology - Abstract
The current study examined how acculturation gap, acculturative stress, parent–child conflict, and behavior problems are related in a sample of Arab American adolescents. Seventy-six parent–child dyads completed questionnaires assessing acculturation, parent–child conflict, and behavior problems. Parents and adolescents reported similar levels of acculturation on American mainstream orientation as well as on Arab heritage orientation. Regression analyses showed that the acculturation gap between parents and children in heritage cultural orientation significantly predicted adolescent behavior problems. Mediation analyses revealed that adolescent-reported parent–child conflict partially mediated the relation between acculturative stress and behavior problems. Parent-reported parent–child conflict partially mediated the relation between the acculturation gap and behavior problems. Current findings highlight the importance of examining adolescents’ and parents’ acculturation as well as the underpinnings of parent–child conflict in Arab American families.
- Published
- 2015
- Full Text
- View/download PDF
9. Dual Biomarkers of Anaerobic Hydrocarbon Degradation in Historically Contaminated Groundwater
- Author
-
Diane. L. Saber, Xiangyang Zhu, Lily Y. Young, Amita. R. Oka, and Craig D. Phelps
- Subjects
Fresh Water ,Polymerase Chain Reaction ,law.invention ,chemistry.chemical_compound ,Denitrifying bacteria ,law ,RNA, Ribosomal, 16S ,Environmental Chemistry ,Anaerobiosis ,Water pollution ,Polymerase chain reaction ,Naphthalene ,biology ,Chemistry ,General Chemistry ,Biodegradation ,biology.organism_classification ,Hydrocarbons ,Biodegradation, Environmental ,Genes, Bacterial ,Environmental chemistry ,Benzylsuccinate synthase ,biology.protein ,Anaerobic exercise ,Biomarkers ,Water Pollutants, Chemical ,Bacteria ,Environmental Monitoring - Abstract
This study reports that ongoing in situ anaerobic hydrocarbon biodegradation at a manufactured gas plant impacted site is occurring, 9 years after the initial investigation. Groundwater samples from the site monitoring wells (MW) were analyzed for biomarkers by GC-MS, end-point PCR, and quantitative PCR (qPCR). Metabolic biomarkers included specific intermediates of anaerobic naphthalene and/or 2-methylnaphthalene degradation: 2-naphthoic acid (2-NA); 5,6,7,8-tetrahydro-2-NA (TH-2-NA); hexahydro-2-NA (HH-2-NA); and carboxylated-2-methylnaphthalene (MNA). The analogues of gene bssA, encoding alpha subunit of enzyme benzylsuccinate synthase, were used as a genetic biomarker. Results indicate 1-2 orders of magnitude higher abundance of total bacteria in the impacted wells than in the unimpacted wells. End-point PCR analysis of bssA gene, with degenerate primers, indicated the presence of hydrocarbon degrading bacteria within the plume. In qPCR analysis, using primers based on toluene-degrading denitrifying or sulfate-reducing/methanogenic bacteria, bssA genes were detected only in MW-24, located downstream from the source. Metabolic biomarkers were detected in multiple wells. The highest abundance of 2-NA (6.7 μg/L), TH-2-NA (2.6 μg/L), HH-2-NA, and MNA was also detected in MW-24. The distribution of two independent biomarkers indicates that the site is enriched for anaerobic hydrocarbon biodegradation and provides strong evidence in support of natural attenuation.
- Published
- 2011
- Full Text
- View/download PDF
10. The Culturally Relevant Assessment of Ebonics-Speaking Children
- Author
-
Sycarah Grant, Evelyn R. Oka, and Jean A. Baker
- Subjects
business.industry ,Knowledge level ,School psychology ,Face (sociological concept) ,Legislation ,Public relations ,Education ,Limited access ,Psychiatry and Mental health ,Pedagogy ,Developmental and Educational Psychology ,Lack of knowledge ,Professional association ,business ,Psychology ,Cultural competence ,Applied Psychology - Abstract
Professional organizations and federal legislation stipulate that assessments of all students must be fair and unbiased. Although these entities provide guidance, there continues to be a gap between guidelines and practice. This article examines the nature of culturally competent practice with Ebonics-speaking youth. Many school psychologists face challenges such as large caseloads, lack of knowledge about Ebonics, and limited access to culturally appropriate assessment materials. The present article fills this gap by providing practitioners with information on the history of Ebonics, implications for the students they assess, and practical ways to address these issues with limited resources.
- Published
- 2009
- Full Text
- View/download PDF
11. Multicultural Issues in Evidence-Based Interventions
- Author
-
Evelyn R. Oka and Colette L. Ingraham
- Subjects
Evidence-based practice ,Multicultural education ,education ,School psychology ,Applied psychology ,Professional development ,Psychological intervention ,Context (language use) ,Education ,Psychiatry and Mental health ,Cultural diversity ,Developmental and Educational Psychology ,Psychology ,human activities ,Applied Psychology ,Cultural pluralism - Abstract
SUMMARY School psychologists involved in the delivery of psychological and educational interventions face the challenge of identifying interventions that will work within their schools. The evidence-based intervention (EBI) approach has received attention as a promising way to identify effective interventions. The national Task Force on Evidence Based Interventions in School Psychology (sponsored by the American Psychological Association Division 16 and the Society for the Study of School Psychology, and endorsed by the National Association of School Psychologists) has developed coding criteria to review, evaluate, and identify efficacious interventions. This paper expands the work of the Multicultural and Diversity Committee of the EBI Task Force and offers direction for school psychologists in selecting and implementing interventions appropriate for their settings. We explore the meaning of EBIs in the context of a diverse world and discuss the cultural considerations that are necessary to responsibly a...
- Published
- 2006
- Full Text
- View/download PDF
12. Acculturation, Acculturative Stress, Religiosity and Psychological Adjustment among Muslim Arab American Adolescents
- Author
-
Anisa N. Goforth, Frederick T. L. Leong, Daniel J. Denis, and Evelyn R. Oka
- Subjects
Health (social science) ,media_common.quotation_subject ,Immigration ,Stressor ,Religious studies ,Arab americans ,Psychodynamics ,Acculturation ,Religiosity ,Psychiatry and Mental health ,Mainstream ,Psychology ,Competence (human resources) ,Social psychology ,media_common - Abstract
Whether born in the United States or being immigrants, Arab American youth may experience challenges related to maintaining their heritage culture’s traditions and values and the degree to which they participate in mainstream American tra4 Anisa Goforth, Evelyn Oka, Frederick Leong, and Daniel Denis ditions. The goals of this research study were to see how acculturation, acculturative stress, and religiosity were associated with psychological adjustment among Muslim Arab American adolescents. One hundred twentyeight Arab American adolescents (ages 11–21) completed measures of demographic characteristics, acculturation, acculturative stress, religiosity, and social desirability. Age, gender, religiosity, and length of time in the U.S. were found to significantly predict heritage cultural orientation but not mainstream cultural orientation. Moreover, acculturation and acculturative stress significantly predicted psychological problems but not overall competence. The implications of the study address how practitioners may consider religion, acculturation, and related stressors when working with Muslim Arab American adolescents.
- Published
- 2014
- Full Text
- View/download PDF
13. Pharmaceutical and Bacteriological Study on Povidone-Iodine Sugar Ointment
- Author
-
Tadashi Shiraishi, R. Oka, and Yoshito Nakagawa
- Subjects
Staphylococcus aureus ,Sucrose ,medicine.medical_specialty ,Time Factors ,medicine.drug_class ,Chemistry, Pharmaceutical ,Drug Storage ,education ,chemistry.chemical_element ,Dermatology ,medicine.disease_cause ,Iodine ,Drug Costs ,Ointments ,Excellent preparation ,Drug Stability ,Iodophors ,Antiseptic ,medicine ,Humans ,Sugar ,Povidone-Iodine ,health care economics and organizations ,Antibacterial agent ,Pressure Ulcer ,Bacteria ,Traditional medicine ,business.industry ,Temperature ,Hydrogen-Ion Concentration ,Methicillin-resistant Staphylococcus aureus ,eye diseases ,humanities ,Surgery ,chemistry ,Evaluation Studies as Topic ,Anti-Infective Agents, Local ,Methicillin Resistance ,business - Abstract
Povidone-iodine sugar ointment is an excellent preparation for the treatment of decubitus. It has been used as an intrahospital preparation made according to the formula each hospital decided on from experience. Although commercial products have also been developed and used, they are too expensive. The efficacy of a povidone-iodine sugar ointment formulation which can be prepared by a single method and which has the stability and antibacterial activity equal to commercially available products was evaluated. As the test drugs, one commercially available product (UP), and three preparations with different formulas (P-1, P-2 and P-3) were used. All of these test drugs were stored at 20 and 40 degrees C. Specimens were sampled immediately after storage and after 20, 60, 90, 120 and 150 days and examined pharmaceutically (measurement of pH value and determinations of available iodine and sucrose levels). For the determination of bacteriological effects, 5 standard strains of 5 genera and 5 strains of methicillin-resistant Staphylococcus aureus (MRSA) were used and the time required to kill the bacteria was determined. For UP and P-3, no changes were seen pharmaceutically after 150 days of storage at 20 and 40 degrees C. However, MRSA could not be killed within 30 min. P-1 and P-2 showed remarkable changes pharmaceutically after 60 days of storage at 40 degrees C and could not be used any more. It became possible to make a preparation of povidone-iodine sugar ointment which has a stability almost similar to that of UP. Moreover, such a preparation can be made at low cost. However, since the bactericidal activity against MRSA was not higher than those of other drugs, the future task is to improve the bactericidal activity.
- Published
- 1997
- Full Text
- View/download PDF
14. Contents, Vol. 195, Supplement 2, 1997
- Author
-
Y. Ihara, S. Oda, S. Ishigo, K. Sato, T. Miyai, I. Matsumoto, T. Kitamura, I.A. Adamietz, K. Oizumi, J. Kumazawa, G. Erdos, Y. Takahashi, H.-D. Boettcher, Y. Yoshimura, N. Hayakawa, R. Niedner, S. Kawahara, T. Kurosaki, A.E. van der Merwe, O. Morita, A. Yamada, Y. Nezu, W. Behrens-Baumann, T. Rikimaru, M. Kondo, K. Yamada, K. Yanagi, H. Kuroki, T. Kunisada, D. Michel, A. Simmons, R. Kawana, Y. Furuya, H. Takada, Erica L. Eason, M. Kanazawa, B. König, O. Nakagomi, K. Sugimoto, S. Chiba, O. Hara, D.G. MacLellan, A. Hoshioka, R. Rahn, V. Schaefer, S. Kawaguchi, M. Arita, K. Reimer, K. Takahashi, W. Fleischer, T. Matsumoto, N. Yoshihara, G.A. Zäch, P. Burkhard, Y. Yoshida, M. Ermini, M. Sakumoto, S. Kondo, A. Lanzendörfer, K. Shindo, Y. Nakagawa, H. Schreier, T. Arata, B. Lanker Klossner, M. Ito, N. Ishiwada, Y. Asano, T. Shiraishi, R. Namba, F. Yamazaki, M. Kamitani, K. Nobukuni, R. Oka, W. König, H.-R. Widmer, T. Yasuda, B. Brögmann, T. Toba, T. Hayabara, H. Hoekstra, J. Iriyama, H. Gümbel, H. Abe, and F. Frey
- Subjects
Dermatology - Published
- 1997
- Full Text
- View/download PDF
15. Factors Contributing to the Psychosocial Adjustment of Ugandan Preschool Children with HIV/AIDS
- Author
-
Bruno Giordani, Michael J. Boivin, Connie Page, Evelyn R. Oka, and Rachelle A. Busman
- Subjects
Coping (psychology) ,Pediatrics ,medicine.medical_specialty ,Home environment ,education ,Human immunodeficiency virus (HIV) ,medicine.disease ,medicine.disease_cause ,Acquired immunodeficiency syndrome (AIDS) ,medicine ,Anxiety ,medicine.symptom ,Psychology ,Psychosocial ,Socioeconomic status ,Clinical psychology - Abstract
This chapter examines the internalizing, externalizing, and total behavior problems of 119 preschool-age children with HIV/AIDS in Uganda. Variables are examined according to an ecological model of stress and coping consistent with the co-constructivist approach proposed by Li (Psychol Bull 129:171–194, 2003). Specifically, the context in which the child is living (e.g., health variables, demographic variables, home environment, and caregiver variables represented by who is caring for the child, caregiver anxiety and depression, and child outcomes (internalizing, externalizing, and total behavior concerns) are examined. A dynamic relationship between the context and child was discovered. Nearly 45 % of the children within the sample exhibited internalizing behavior concerns. The caregiving environment, as well as caregiver adjustment (anxiety and depression), was predictive of child internalizing behaviors. Furthermore, child characteristics and demographic variables (gender, medication status, and socioeconomic status) contributed to the adjustment of the caregiver. These findings demonstrate the dynamic and reciprocal relationship between young children with HIV/AIDS in Uganda and the context in which they live.
- Published
- 2013
- Full Text
- View/download PDF
16. Examining the Psychosocial Adjustment and School Performance of Ugandan Children with HIV/AIDS
- Author
-
Rachelle A. Busman, Evelyn R. Oka, Bruno Giordani, and Michael J. Boivin
- Subjects
medicine.medical_specialty ,Transmission (medicine) ,Human immunodeficiency virus (HIV) ,virus diseases ,medicine.disease ,medicine.disease_cause ,Mental health ,Virus ,School performance ,Acquired immunodeficiency syndrome (AIDS) ,Quality of life ,Environmental health ,medicine ,Psychology ,Psychiatry ,Psychosocial - Abstract
Every day, 1,100 children around the world are infected with human immunodeficiency virus (HIV), most as a result of mother-to-child transmission (MTCT) of the virus [United Nations Program on HIV/AIDS (UNAIDS) 2007]. In 2007 alone, an estimated 420,000 children worldwide were newly infected almost exclusively through MTCT (UNICEF 2008).
- Published
- 2013
- Full Text
- View/download PDF
17. Functional Proteomic Profiling of Phosphodiesterases Using SeraFILE Separations Platform
- Author
-
Matthew Kuruc, Ketan M. Gujarathi, Swapan Roy, and Amita. R. Oka
- Subjects
Article Subject ,Proteomic Profiling ,Drug discovery ,Phosphodiesterase ,Computational biology ,Biology ,Rat brain ,Bioinformatics ,Biochemistry ,Bovine brain ,Proteome ,Biomarker discovery ,Molecular Biology ,Research Article - Abstract
Functional proteomic profiling can help identify targets for disease diagnosis and therapy. Available methods are limited by the inability to profile many functional properties measured by enzymes kinetics. The functional proteomic profiling approach proposed here seeks to overcome such limitations. It begins with surface-based proteome separations of tissue/cell-line extracts, using SeraFILE, a proprietary protein separations platform. Enzyme kinetic properties of resulting subproteomes are then characterized, and the data integrated into proteomic profiles. As a model, SeraFILE-derived subproteomes of cyclic nucleotide-hydrolyzing phosphodiesterases (PDEs) from bovine brain homogenate (BBH) and rat brain homogenate (RBH) were characterized for cAMP hydrolysis activity in the presence (challenge condition) and absence of cGMP. Functional profiles of RBH and BBH were compiled from the enzyme activity response to the challenge condition in each of the respective subproteomes. Intersample analysis showed that comparable profiles differed in only a few data points, and that distinctive subproteomes can be generated from comparable tissue samples from different animals. These results demonstrate that the proposed methods provide a means to simplify intersample differences, and to localize proteins attributable to sample-specific responses. It can be potentially applied for disease and nondisease sample comparison in biomarker discovery and drug discovery profiling.
- Published
- 2012
- Full Text
- View/download PDF
18. Nimonic compound exhaust valve spindles for diesel engines via hot isostatic pressing
- Author
-
Y. Izaki, T. Moriyama, R. Oka, K. Umeda, Y. Nishioka, and T. Tanaka
- Subjects
Austenite ,Materials science ,Mechanical Engineering ,Metallurgy ,Weldability ,Nimonic ,Condensed Matter Physics ,Corrosion ,Mechanics of Materials ,Hot isostatic pressing ,Stellite ,Powder metallurgy ,General Materials Science ,Composite material ,Combustion chamber - Abstract
Until the present time the materials used for exhaust valve spindles for diesel engines have comprised a main body of heat resistant austenite steel with a Stellite layer covering the seat area. Recently, to satisfy increasing demands for higher efficiency of engines, a forged Nimonic 80 exhaust valve spindle has been developed. This valve spindle has higher strength and hot corrosion resistance than conventional austenite steel valves. This paper introduces a compound type Nimonic 80A-austenite steel valve spindle produced via hot isostatic pressing. Nimonic 80A powder metal is consolidated and diffusion bonded to an austenite spindle body. The seat area and the total combustion chamber side of the spindle are clad using Nimonic 80A. The compound valve spindle produced via hot isostatic pressing has the same performance as a forged Nimonic 80A spindle and in addition it has improved repair weldability and hot corrosion resistance compared with the forged Nimonic 80A spindle valve. Because less of the expensive Nimonic 80A material is used, there is an added advantage in that the cost of the valve would be cheaper. Successful engine test results are also described
- Published
- 1994
- Full Text
- View/download PDF
19. Identification of critical members in a sulfidogenic benzene-degrading consortium by DNA stable isotope probing
- Author
-
Lee J. Kerkhof, Lily Y. Young, Adam C. Mumford, Lora McGuinness, Craig D. Phelps, and Amita. R. Oka
- Subjects
clone (Java method) ,DNA, Bacterial ,Stable-isotope probing ,Sulfides ,Applied Microbiology and Biotechnology ,DNA, Ribosomal ,chemistry.chemical_compound ,Isotopes ,RNA, Ribosomal, 16S ,Environmental Microbiology ,Benzene ,Phylogeny ,Ecology ,biology ,Bacteria ,Hybridization probe ,Sequence Analysis, DNA ,biology.organism_classification ,Molecular biology ,chemistry ,Biochemistry ,GenBank ,Biodegradation ,Restriction fragment length polymorphism ,DNA Probes ,DNA ,Polymorphism, Restriction Fragment Length ,Food Science ,Biotechnology - Abstract
Stable isotope probing (SIP) was used to identify the active members in a benzene-degrading sulfidogenic consortium. SIP-terminal restriction fragment length polymorphism analysis indicated that a 270-bp peak incorporated the majority of the 13 C label and is a sequence closely related to that of clone SB-21 (GenBank accession no. AF029045). This target may be an important biomarker for anaerobic benzene degradation in the field.
- Published
- 2008
20. Acoustic Echo Cancellation Algorithm Tolerable for Double Talk
- Author
-
Kensaku Fujii, R. Oka, N. Saitoh, and Mitsuji Muneyasu
- Subjects
Engineering ,business.industry ,Acoustics ,Echo (computing) ,Residual ,Double-talk ,Adaptive filter ,Computer Science::Sound ,Filter (video) ,Control system ,Kernel adaptive filter ,Hardware_ARITHMETICANDLOGICSTRUCTURES ,business ,Algorithm ,Root-raised-cosine filter - Abstract
This paper proposes a step size control method capable of steadily canceling acoustic echo resisting double talk. The method is characterized by applying a sub-adaptive filter to the control. The step size and the number of taps of the sub- adaptive filter are larger and fewer than those of the main adaptive filter used for canceling the acoustic echo, respectively. Accordingly, the sub-adaptive filter can reduce the residual echo more rapidly than the main adaptive filter. The proposed method applies the step size calculated using the residual echo to the main adaptive filter, and thereby, quickly and steadily reduces the acoustic echo. This paper finally verifies that the proposed method can provide almost the same convergence speed as that obtained by applying a fixed large step size to the main adaptive filter.
- Published
- 2008
- Full Text
- View/download PDF
21. Evaluation of myocardial perfusion using three-dimensional myocardial contrast echocardiography
- Author
-
A.N. DeMaria, K.D. May-Newman, C.L. Chen, R. Haslim, and R. Oka
- Subjects
Cardiac function curve ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Blood volume ,Blood flow ,Balloon ,medicine.anatomical_structure ,Ventricle ,Internal medicine ,medicine ,Cardiology ,Infusion pump ,3D ultrasound ,business ,Perfusion - Abstract
The distribution of coronary blood volume is of fundamental importance to cardiac function. Previous investigators have demonstrated that myocardial vascular volume varies with both perfusion pressure and contraction. The purpose of this study is to measure vascular volume in an isolated rabbit heart model under a variety of controlled mechanical conditions using 3-D MCE. Isolated rabbit hearts were perfused with a room temperature crystalloid solution in a Langendorff perfusion apparatus and a small balloon was placed inside the left ventricle and attached to a volume infusion pump. Digital images of the heart were acquired with a Volumetrics 3D ultrasound scanner at perfusion pressures of 0, 30, and 50 mmHg without and with a microbubble-based contrast agent. LV pressure was held at a constant level of 0 mmHg. Regional videointensity and LV area were measured from short axis images in six hearts. Background-subtracted videointensity increased linearly with normalized coronary blood flow (R/sup 2/=.99), demonstrating the ability of this method to noninvasively determine myocardial perfusion. Coronary vascular volume was estimated using a calibration technique and assuming the perfused myocardium may be modeled as a composite material, consisting of incompressible tissue and distensible vessels. Coronary volume was estimated to be 16-24% of the myocardium, comparable to values found in previous studies. Our method may be extended to noninvasively measuring regional coronary volume in patients, thereby providing an additional tool for physicians.
- Published
- 2005
- Full Text
- View/download PDF
22. Figure-based writer verification by matching between an arbitrary part of registered sequence and an input sequence extracted from on-line handwritten figures
- Author
-
H. Kameya, R. Oka, and S. Mori
- Subjects
Sequence ,Matching (graph theory) ,Handwriting recognition ,Intelligent character recognition ,business.industry ,Computer science ,Speech recognition ,Feature extraction ,Pattern recognition ,Artificial intelligence ,Line (text file) ,Spotting ,business - Abstract
This paper propose a method of writer verification basedon on-line features extracted from a process of drawing afigure, and evaluate its performance on handdrawn figuresby genuine writers and pretenders. In the proposed method,a person in registration writes only the reference figure,which is composed of as many parts as possible and theperson can be verified with a arbitrary part of the referencefigure. The verification is based on a spotting methodcalled CDP (Continuous Dynamic Programming). Fromsome requirements in authentication system, the proposedmethod is tested through some experiments using figures.The error rates in the experiment were different dependingon conditions such as kind of on-line features, minimumnumber of strokes comprised in acceptable test sequence asinput, figure for determination of threshold and the genuinewriter. The result of the experiment shows that the proposedmethod is effective.
- Published
- 2005
- Full Text
- View/download PDF
23. Phonemic recognition of each frame with vector field feature using continuous dynamic programming
- Author
-
R. Oka
- Subjects
Matching (graph theory) ,business.industry ,Computer science ,Speech recognition ,Feature vector ,Frame (networking) ,Feature extraction ,Computer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing) ,Pattern recognition ,Computer Science::Sound ,Feature (computer vision) ,Pattern recognition (psychology) ,Feature (machine learning) ,Artificial intelligence ,Pattern matching ,business - Abstract
The purpose of the paper is to propose an algorithm for pseudo-phonemic labelling of each frame feature in a continuous speech. The algorithm is consisting of the two key concepts; 1) Utilization of speech feature composed of spectrum and vector field feature of spectrum based on Vector Field Model of Speech for realizing a system which works speaker-independently, and 2) Application of a new algorithm for accumulating pseudo-phonemic evidence of each frame based on both Continuous Dynamic Programming (CDP) and Partial Matching Method.
- Published
- 2005
- Full Text
- View/download PDF
24. Continuous speech recognition on the bases of vector field model for segmentation and feature extraction, and continuous dynamic programming for pattern matching
- Author
-
R. Oka
- Subjects
business.industry ,Computer science ,Feature vector ,Speech recognition ,Feature extraction ,Pattern recognition ,Computer Science::Sound ,Pattern recognition (psychology) ,Feature (machine learning) ,Vector field ,Segmentation ,Transient (computer programming) ,Pattern matching ,Artificial intelligence ,business - Abstract
A new model called Vector Field Model is proposed for providing new algorithms of both segmentation and feature extraction in order to recognize phonemic units in continuous speech spoken by many speakers. The original vector field is obtained by differentiating a time-frequency pattern (the output of band-pass filters). In order to extract steady , increasing transient or decreasing transient feature of the point on the time-frequency pattern, three auxiliary vector fields are created by characterizing coherent orientations of vectors. The crowded vectors in an arbitary auxiliary vector field produce a pseudo-phonemic segment. Recognition of /VCV/ is carried out by applying so-called Continuous Dynamic Programming to a segment sequence pattern.
- Published
- 2005
- Full Text
- View/download PDF
25. Large decreases in insulin requirement occurred repeatedly in two pregnancies in a type 1 diabetic woman
- Author
-
T. Iura, R. Oka, and S. Miyamoto
- Subjects
Adult ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Third trimester ,Endocrinology ,Insulin resistance ,Pregnancy ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Hypoglycemic Agents ,Insulin ,Type 1 diabetes ,Dose-Response Relationship, Drug ,business.industry ,Insulin dosage ,General Medicine ,medicine.disease ,Pregnancy Complications ,Diabetes Mellitus, Type 1 ,Gestation ,Female ,business - Abstract
Whereas the increase in insulin requirement in late gestation is well described in diabetic pregnancy, a decrease in insulin dosage in the end of the third trimester has also been noted in clinical experience and the prevention of hypoglycaemia is important. Here we report a large decrease (over 50%) in the final few weeks of her two gestations in a woman with type 1 diabetes mellitus.
- Published
- 2004
26. Reactor vibration analysis in consideration of coupling between the magnetic field and vibration
- Author
-
Tetsuhiro Ishikawa, Y. Suzuki, H. Sugiyama, R. Oka, Y. Kawase, M. Tatsuno, and E. Baba
- Subjects
Vibration ,Coupling ,Electromagnetic field ,Engineering ,Magnetic core ,business.industry ,Acoustics ,Analytical technique ,Electronic engineering ,business ,Noise (radio) ,Electromagnetic pulse ,Magnetic field - Abstract
This paper describes how the cause of noise in a hybrid vehicle reactor was elucidated by the development of technology to analyze the coupling between the magnetic field and vibration in the high-frequency range (5 to 10 kHz) and how reactor noise was reduced as a result. To date, magnetic field and vibration analyses, for reactors have been done but mainly within conditions at the commercial frequency range (around 60 Hz). (Hagiwara, S, 1982), (Hori, Y, 1995), (Yanari, T, 1996). This paper describes how the reactor behavior in the high-frequency range (5 to 10 kHz) was clarified by constructing a suitable model and analyzing electromagnetic fields and vibration phenomena occurring in it. Experimental results were also used for the analyses. In addition, this analytical technique was used to elucidate the cause of noise and to develop a new form of reactor to reduce noise. As a result, noise was reduced by 10 dB or more.
- Published
- 2004
- Full Text
- View/download PDF
27. Automatic model construction for a user oriented task using speech utterances
- Author
-
R. Oka, T. Endo, and S. Sakurai
- Subjects
Knowledge representation and reasoning ,Computer science ,business.industry ,User modeling ,Speech recognition ,Intelligent decision support system ,Full text search ,Inference ,computer.software_genre ,Task (project management) ,User oriented ,Artificial intelligence ,business ,computer ,Natural language processing - Abstract
We propose a method to self-organize a user model for realizing a text search system. The method self-organizes a model from phoneme sequences and their texts using 6 basic rules. An inference method associated with the self-organized model searches texts corresponding to inputted phoneme sequences. Experiments using 50 voice waveforms of 10 speakers show that the self-organized model is useful to realize a text search system and is robust for noisy speech utterances.
- Published
- 2003
- Full Text
- View/download PDF
28. Spotting-based global positioning with nonmonotonic continuous DP for mobile robots using image sequences
- Author
-
S. Nozaki, Takuichi Nishimura, and R. Oka
- Subjects
Gesture recognition ,business.industry ,Robustness (computer science) ,Computer science ,Global Positioning System ,Robot ,Computer vision ,Mobile robot ,Artificial intelligence ,Kalman filter ,business ,Mobile robot navigation - Abstract
We develop a technique for robustly positioning and guiding mobile robots in the real world, such as offices and homes, by using topological maps consisting of image sequences capturing the environment. This technique uses reference interval-free continuous dynamic programming (DP) which allows positioning by spotting, but it restricts the direction of mobile robot navigation to the same one as the map creation. We propose to use the nonmonotonic continuous DP for gesture recognition, to allow the positioning of a robot within the same framework even when it navigates backwards or stops. We also propose the use of average values of local features in each section generated by horizontally dividing the omnidirectional view as rotation-invariant features to allow global positioning of a robot regardless of its direction. In addition, we demonstrate the usefulness of this technique through evaluation experiments using mobile robots.
- Published
- 2003
- Full Text
- View/download PDF
29. Recognition of gestures using morphological features of networks made of gesture motion images and word sequences
- Author
-
T. Mukai, R. Oka, H. Yabe, and Takuichi Nishimura
- Subjects
Computer science ,Gesture recognition ,business.industry ,Motion estimation ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Computer vision ,Artificial intelligence ,business ,Motion (physics) ,Word (computer architecture) ,Sentence ,Gesture - Abstract
We propose a method to recognize human gestures using both motion images and text. The method uses two kinds of network models obtained from two kinds of sequences in a style of self-organization. We can extract both so-called common and singular parts of a gesture by analyzing the topology of the network of gesture motion images. If the order of movements in a gesture motion image matches with that of words included in a corresponding sentence, then we can also extract both so-called common and singular parts of the network model of test. The proposed method for recognizing gestures uses morphological features between two networks made of gesture motion images and word sequences. We show the usefulness of the method through an experiment using a database composed of pairs of gesture motion images and text.
- Published
- 2003
- Full Text
- View/download PDF
30. An active microphone method for speech recognition systems
- Author
-
M. Nakazawa, R. Oka, S. Nagaya, and T. Endo
- Subjects
Microphone ,Gesture recognition ,Computer science ,ComputerSystemsOrganization_MISCELLANEOUS ,Interface (computing) ,Speech recognition ,Noise-canceling microphone ,Loudspeaker ,Sensor fusion ,Speaker recognition ,Impulse response - Abstract
We propose a method to recognize human speech without the restriction that the speaker should be close to the microphone for the multiple modal interface. This method has the following features: 1) to control the microphone directivity for improvement of S/N ratio by using the speaker's position estimated by the result of gesture recognition, 2) to compose the impulse response of the transfer characteristic between speakers and microphones into reference data of the recognition system. We describe the active microphone method in detail, and show its effectivity through several experiments. Then, we discuss the results.
- Published
- 2002
- Full Text
- View/download PDF
31. Towards the integration of spontaneous speech and gesture based on spotting method
- Author
-
T. Nishimura and R. Oka
- Subjects
business.industry ,Computer science ,Speech recognition ,Feature vector ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Pattern recognition ,Image segmentation ,Spotting ,Edge detection ,Motion estimation ,Artificial intelligence ,Hidden Markov model ,business ,Gesture - Abstract
A spotting algorithm to recognize the meanings of human gestures from motion images is proposed. Feature vectors are extracted from temporal edge image. And input image sequences are matched with models by spotting algorithm. The spotting algorithm removes the need for temporal segmentation of gesture duration and introduces frame-wise recognition. In this paper, a new spotting method called nonmonotonic continuous DP is proposed for spotting gestures and their variations such as reverse, partial and stop motions. We showed the effectiveness of the new spotting method.
- Published
- 2002
- Full Text
- View/download PDF
32. The slot expression for topic spotting and topic summary in spontaneous speech
- Author
-
R. Oka and M. Nakazawa
- Subjects
Thesaurus (information retrieval) ,business.industry ,Computer science ,Speech recognition ,Feature extraction ,Spotting ,Broadcasting ,computer.software_genre ,Speech processing ,Expression (mathematics) ,Feature (machine learning) ,Artificial intelligence ,business ,computer ,Natural language processing ,Word (computer architecture) - Abstract
This paper proposes two new methods of how to carry out automatic topic spotting in continuous speech and how to describe its summary in the form of the slot expression. The topic spotting works independently of both speakers and topics. The method of topic spotting is based on a dialogue model to segment a topic using only a surface feature of continuous speech. The spotted speech are selected by the co-occurrence relations and are classified by the word thesaurus. We evaluated our methods using the speech of the broadcasting news and the spoken dialogue speech. The result shows that detection quality was over 80% on the broadcasting news.
- Published
- 2002
- Full Text
- View/download PDF
33. Continuous retrieval of video using segmentation-free query
- Author
-
R. Oka, N. Sekimoto, T. Nishimura, and H. Takahashi
- Subjects
Computer science ,Frame (networking) ,Feature extraction ,Image segmentation ,computer.software_genre ,Query expansion ,Histogram ,Queries per second ,Visual Word ,Data mining ,Document retrieval ,Cluster analysis ,Image retrieval ,computer - Abstract
A retrieval method, called running time interval clustering (Rutic), is proposed. The method detects time sequence intervals similar to the query time sequence in a vast database of time sequences such as video and audio data. Conventional methods, such as RIFCDP, handled queries of any interval lengths, but they require a relatively high computational burden and are not suitable for real-time retrieval from a large database. The Rutic method allows retrieval results to be output for each input frame of the time sequence queries, thus enabling retrieval from a database without segmentation. The computational burden of the Rutic method is so small that it enables the so-called real-time spotting retrieval. This report describes the algorithm of the Rutic method, and verifies its validity through comparison with other methods based on image search experiments.
- Published
- 2002
- Full Text
- View/download PDF
34. Recognition of human motion behaviors using multiple omni-directional vision sensors
- Author
-
Takushi Sogo, T. Nishimura, Hiroshi Ishiguro, and R. Oka
- Subjects
business.industry ,Computer science ,Feature vector ,3D single-object recognition ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Motion (physics) ,Feature (computer vision) ,Structure from motion ,Computer vision ,Artificial intelligence ,Image sensor ,business ,Feature detection (computer vision) - Abstract
In order to obtain flexibility of recognition system of human motion behaviors, omni-directional vision sensors are used for both tracking humans and getting multiple. views of different directions that allows human to move with natural behavior in large area. First, a vision-based aspect model is proposed which realize the recognition independent of the human-direction. It contains feature vector sequences that were taken from all direction around the human. Next, the authors' appearance-based feature extraction method is demonstrated to be useful for whole body motion recognition. A new technique, spatio-temporal continuous dynamic programming, allows a human to rotate even when he is doing a motion behavior.
- Published
- 2002
- Full Text
- View/download PDF
35. Overexpression of latent transforming growth factor-beta 1 (TGF-beta 1) binding protein 1 (LTBP-1) in association with TGF-beta 1 in ovarian carcinoma
- Author
-
T, Higashi, T, Sasagawa, M, Inoue, R, Oka, L, Shuangying, and K, Saijoh
- Subjects
Ovarian Neoplasms ,endocrine system diseases ,Reverse Transcriptase Polymerase Chain Reaction ,Overexpression ,Blotting, Western ,Intracellular Signaling Peptides and Proteins ,Gene Expression ,LTBP‐1 ,TGF‐β1 ,Adenocarcinoma, Mucinous ,Immunohistochemistry ,Article ,Cystadenocarcinoma, Serous ,Latent TGF-beta Binding Proteins ,Transforming Growth Factor beta ,Cystadenoma, Mucinous ,Humans ,Female ,RNA, Messenger ,Carrier Proteins ,Ovarian carcinoma - Abstract
Using the differential display method, latent transforming growth factor-beta 1 (TGF-beta 1) binding protein 1 (LTBP-1) mRNA was identified as one of the enriched mRNAs in ovarian carcinoma tissues after isolation of genes responsible for the development of ovarian cancer. Semi-quantitative reverse transcription (RT)-PCR analysis showed that expression of LTBP-1 and TGF-beta 1 mRNAs was much higher in both serous and mucinous adenocarcinomas than in their benign counterparts, including serous and mucinous cystadenomas and cystadenomas of low malignant potential (LMPs). Immunohistochemical analysis demonstrated that only proliferating benign adenoma cells were immunoreactive for both LTBP-1 and TGF-beta 1 proteins. In contrast, most serous and mucinous adenocarcinoma cells and their surrounding stroma were intensely immunoreactive for LTBP-1 and TGF-beta 1. LTBP-1 and TGF-beta 1 proteins, and their complex forms were identified in ovarian carcinoma cell lines and in their culture media by western blot analysis, suggesting these products were produced in ovarian carcinoma cells. RT-PCR analysis demonstrated that LTBP-1L, one of the LTBP-1 transcripts that has a strong activity in targeting the latent form of TGF-beta 1 to extracellular matrix (ECM), was predominantly expressed in ovarian carcinomas. Taken together, the results suggest that upregulation of LTBP-1 in ovarian carcinoma cells may have an important role in distributing TGF-beta1 in the stromal tissues surrounding carcinoma cells.
- Published
- 2001
36. Central serotonergic mechanisms on head twitch response induced by benzodiazepine receptor agonists
- Author
-
Takeshi Tadano, Osamu Nakagawasai, M. Hozumi, M. Mizugaki, Yuichiro Arai, T. Hishinuma, K. Tan-no, R. Oka, N. Satoh, Hiroyasu Kinemuchi, Kensuke Kisara, Hajime Yasuhara, and Fukie Niijima
- Subjects
Male ,medicine.medical_specialty ,Triazolam ,medicine.drug_class ,medicine.medical_treatment ,Intraperitoneal injection ,Pharmacology ,Serotonergic ,Piperazines ,Head-twitch response ,Mice ,Internal medicine ,Fluoxetine ,medicine ,Animals ,Hypnotics and Sedatives ,Dihydroxytryptamines ,GABA-A Receptor Agonists ,Receptor ,Zopiclone ,Benzodiazepine ,8-Hydroxy-2-(di-n-propylamino)tetralin ,Behavior, Animal ,business.industry ,General Medicine ,Receptors, GABA-A ,Estazolam ,Serotonin Receptor Agonists ,Endocrinology ,Anti-Anxiety Agents ,Receptors, Serotonin ,Ketanserin ,Serotonin Antagonists ,business ,Azabicyclo Compounds ,Selective Serotonin Reuptake Inhibitors ,medicine.drug - Abstract
Intraperitoneal injection of benzodiazepine receptor agonists (estazolam, zopiclone, triazolam: 0.03–0.24 mmol/kg) induces the head twitch response (HTR). The present study was undertaken to examine the possible participation of the serotonergic system in the mechanism of head twitches induced by benzodiazepine receptor agonists (BZ-RAs). The HTR induced by BZ-RAs was suppressed by pretreatment with ketanserine (1 mg/kg, i.p.), a selective 5-HT2 receptor antagonist. Pretreatment with fluoxetine (10 mg/kg, i.p.), a 5-HT reuptake inhibitor, and 8-hydroxy-2-(di-n-propylamino)tetralin, a 5-HT1A receptor agonist, also suppressed the HTR induced by BZ-RAs. These results suggest that the HTR induced by BZ-RAs may be the result of an activation of postsynaptic 5-HT2 receptors, probably due to direct action.
- Published
- 2001
37. [A case of progressive dystonia with serum anti-neuronal antibodies against to the basal forebrain cholinergic neurons]
- Author
-
H, Tanaka, H, Araki, T, Tazaki, R, Oka, K, Tsukasa, and J, Oki
- Subjects
Male ,Neurons ,Dystonia ,Prosencephalon ,Adolescent ,Humans ,Acetylcholine ,Autoantibodies - Published
- 1999
38. Making Connections Efficiently: A Comparison of Two Approaches Used by College Students to Construct Networks
- Author
-
Christina De Simone, Selma Tischer, and Evelyn R. Oka
- Subjects
Modalities ,Recall ,Control (management) ,Developmental and Educational Psychology ,Level of detail (writing) ,Cognition ,Psychology ,Construct (philosophy) ,Education ,Test (assessment) ,Cognitive psychology ,Task (project management) - Abstract
This study compared the effects of two approaches to networking. Two intact classes of college students participated in this study. The major focus of this study was to examine the extent to which the mental construction of networks was sufficient for recall to occur. Two intact classes of students participated in this study. Experimental participants were taught to construct their own networks both on paper and mentally while control participants were not. Recall of ideas was assessed at the pretest and at the posttest using a free-written recall task and a multiple-choice test. The results showed that networking mentally is as effective for recalling ideas and more time-efficient than networking on paper. Moreover, participants used different networking modalities depending on the passage to be read and the level of detail they are attempting to recall. The results are promising as they provide college students with a powerful tool that encourages cognitive processing without unnecessarily depleting their time resources. However, the results of this study also reveal that some initial experience with the strategy is necessary. Copyright 1999 Academic Press.
- Published
- 1999
39. Comparative Evaluation of Metallic Screws in the Repair of Tibial Eminence Avulsion Fractures
- Author
-
A. Lowry, D. Duncan, A. Mahar, R. Oka, H. Chambers, and B. Gillingham
- Subjects
General Medicine ,General Biochemistry, Genetics and Molecular Biology - Published
- 2005
- Full Text
- View/download PDF
40. Effect of time-spatial size of motion image for localization by using the spotting method
- Author
-
S. Nagaya, H. Kojima, T. Nishimura, R. Oka, S. Nozaki, A. Held, and Y. Ito
- Subjects
Dynamic programming ,Robustness (computer science) ,business.industry ,Frame (networking) ,Robot ,Mobile robot ,Computer vision ,Motion planning ,Image segmentation ,Artificial intelligence ,Autonomous robot ,business ,Mathematics - Abstract
We have been developing a localization method for an autonomous robot without using any prior knowledge or assumptions about the environment. The method is general and robust and can be used in real world robot tasks. With a map description based on a reduced image sequence, we detect a frame sequence in the map which matches an input frame sequence, by means of reference interval-free continuous dynamic programming (RIFCDP). The method can cope with changes in the robot's speed because RIFCDP can spot arbitrary frame sequences by nonlinear matching. In this paper, we show a real-time localization system, and we illustrate the effectiveness of our method in the real world by some evaluation experiments.
- Published
- 1996
- Full Text
- View/download PDF
41. [Transposition of the great arteries]
- Author
-
R, Oka and H, Yamashita
- Subjects
Diagnosis, Differential ,Transposition of Great Vessels ,Humans - Published
- 1996
42. Influence of Mechanical Vibration and Losses Under AC Operating in Bi-2223 Tapes With Ionic Liquid Impregnation
- Author
-
K. Nishimura, R. Oka, T. Takagi, and K. Nakamura
- Subjects
Materials science ,High-temperature superconductivity ,Liquid nitrogen ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Magnetic field ,law.invention ,Vibration ,chemistry.chemical_compound ,Nuclear magnetic resonance ,chemistry ,Electromagnetic coil ,law ,Grease ,Ionic liquid ,Electrical and Electronic Engineering ,Composite material ,Superconducting Coils - Abstract
Mechanical loss in superconducting coils is one of the important parameters for the stability of high temperature superconducting coils (HTS coil). We prepared three kinds of impregnations (no impregnation, ionic liquid grease), measured the AC loss of the Bi-2223 tape under DC magnetic field in liquid nitrogen and quantitatively estimated the relation between the impregnation and losses. As a result, the loss can be reduced about 40% by using ionic liquid compared with no impregnation. We consider that the tape impregnated with ionic liquid is effective to reduce the AC loss. The results become fundamental data to reduce the AC loss of conduction-cooled HTS coils.
- Published
- 2012
- Full Text
- View/download PDF
43. [Anorectal malformations]
- Author
-
R, Oka
- Subjects
Male ,Rectum ,Anal Canal ,Humans ,Female ,Child - Published
- 1994
44. [Congenital coronary arterial fistula drained to the coronary sinus--a case report]
- Author
-
H, Yamamoto, K, Goh, N, Akasaka, T, Sasajima, Y, Kubo, and R, Oka
- Subjects
Coronary Vessel Anomalies ,Arteriovenous Fistula ,Humans ,Infant ,Female - Abstract
We report a very rare case of an infant with coronary arterial fistula in whom the communication between a dilated right coronary artery and the coronary sinus was found. The patient was 1-year-old. She had pulmonary congestion and cardiomegaly due to the left-to-right shunt through the fistula, and underwent ligations of the fistula. Ligations of the fistula was indicated because the patient was too small to undergo a fistula resection and coronary arterial bypass grafting. Although the patient had a successful post-operative course, we are paying attention to the aneurysmal change of the dilated right coronary artery proximal to the site of ligations.
- Published
- 1994
45. ['Extended aortic arch anastomosis' in Shone's anomaly--a case report]
- Author
-
H, Yamamoto, K, Goh, N, Akasaka, N, Azuma, Y, Kubo, and R, Oka
- Subjects
Anastomosis, Surgical ,Infant, Newborn ,Humans ,Mitral Valve ,Aorta, Thoracic ,Female ,Aortic Stenosis, Subvalvular ,Aortic Coarctation - Abstract
We report a case of a newborn with Shone's anomaly in whom the parachute mitral valve, mild subaortic stenosis, hypoplastic aortic arch, and severe coarctation of the aorta were found. The patient was 10 days old, who had symptoms of low output syndrome due to the progressive obstruction of patent ductus arteriosus, underwent "extended aortic arch anastomosis" to repair the hypoplastic aortic arch and severe coarctation of the aorta. This surgical procedure, resulting in a successful post-operative course of the patient, might be effective in such anomalies.
- Published
- 1994
46. Spotting Recognition of Human Gestures from Motion Images
- Author
-
S. Seki, R. Oka, and K. Takahashi
- Subjects
Computer science ,business.industry ,Computer vision ,Artificial intelligence ,Spotting ,business ,Motion (physics) ,Gesture - Published
- 1994
- Full Text
- View/download PDF
47. [Variance of signal-averaged electrocardiographic parameters with age in normal children]
- Author
-
A, Tsuchida and R, Oka
- Subjects
Electrocardiography ,Adolescent ,Child, Preschool ,Age Factors ,Infant, Newborn ,Humans ,Infant ,Signal Processing, Computer-Assisted ,Child - Abstract
The high-frequency components of the surface QRS was analyzed quantitatively in 87 normal infants and children. The subjects were categorized in 4 groups by age; Group A: one day (n = 27), Group B: 1-5 years (n = 20), Group C: 6-10 years (n = 20), Group D: 11-15 years (n = 20), and the results were compared among the 4 groups. Signal-averaging and high-pass, bidirectional and digital filtering were used for analysis. The total duration of the QRS, the duration of the low-amplitude signals (40 microV) in the terminal portion of the QRS (U 40), the amplitude of the signals in the QRS (RMS; QRS) and the amplitude of the last 40 msec of the QRS (RMS 40) were measured at high-pass filter frequency settings of 25, 40, 60 and 100 Hz. Statistical analysis was performed with the unpaired t-test. Differences were considered significant if p0.05. The results were as follows: 1. At all filters, the durations of the QRS and U 40 were longer in the order of Groups ABCD, and the amplitude of the RMS; QRS and RM 40 were greater in the order of Groups DCBA. 2. There were significant differences in the QRS between the groups at all filters. 3. There were significant differences in U 40 between the groups except between Groups B and C at 25-Hz filter, but at 40-, 60-, 100-Hz filters, there were no significant differences among Groups B, C and D.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
48. 362 EFFECT OF INTERNAL AND EXTERNAL ROTATION ON STRAIN IN THE ROTATOR CUFF: Table
- Author
-
R. Pedowitz, R. Oka, A. Lowry, and A. Mahar
- Subjects
musculoskeletal diseases ,Materials science ,Shoulders ,Soft tissue ,Strain (injury) ,General Medicine ,Anatomy ,musculoskeletal system ,medicine.disease ,General Biochemistry, Genetics and Molecular Biology ,Tendon ,medicine.anatomical_structure ,Tearing ,Cuff ,medicine ,Rotator cuff ,Strain gauge - Abstract
Purpose Recurrence of tearing following rotator cuff repairs are thought to result from varying strain within the cuff as the shoulder is moved through different anatomical positions. The purpose of this study was to measure strains in the anterior, midline, and posterior aspects of the rotator cuff tendon under dynamic loading with internal and external rotation. Methods Two fresh bovine shoulders (16-week old) were dissected, leaving the infraspinatus tendon intact. Shoulders were mounted to a servohydraulic materials testing machine modified to allow internal and external rotation of the humeral head. Three soft tissue strain gages were attached to the tendon at the anterior, middle, and posterior positions. After preconditioning, the tendon underwent cycling loading between 10-100N of tension for 200 cycles. Strain gage data (mm) was recorded at 5Hz for the duration of the test. Testing was repeated at 15 and 30 degrees of both internal and external rotation. (Table) Conclusion Assessing the repair sensitivity to its location on the tendon, and hence the loading profile of the tendon, is important in evaluating repair and subsequent treatment. The strain magnitudes seen in the data show dramatically greater strains in the posterior aspect of the tendon when the shoulder is rotated. The directions of strain are partially explained by an artifact of the clamping mechanism utilized. Further investigation is necessary to refine these techniques and further elucidate the relationship between local strain and shoulder position.
- Published
- 2005
- Full Text
- View/download PDF
49. 214 COMPARATIVE EVALUATION OF METALLIC SCREWS IN THE REPAIR OF TIBIAL EMINENCE AVULSION FRACTURES: Table
- Author
-
A. Lowry, B. Gillingham, A. Mahar, H. Chambers, D. Duncan, and R. Oka
- Subjects
musculoskeletal diseases ,Orthodontics ,medicine.medical_specialty ,Universal testing machine ,business.industry ,Anterior cruciate ligament ,Stiffness ,General Medicine ,equipment and supplies ,musculoskeletal system ,General Biochemistry, Genetics and Molecular Biology ,Surgery ,Avulsion ,Fixation (surgical) ,surgical procedures, operative ,medicine.anatomical_structure ,Ultimate tensile strength ,medicine ,Osteotome ,Tibia ,medicine.symptom ,business - Abstract
Purpose Pediatric tibial eminence avulsion fractures occur when immature subchondral bone structurally yields before the anterior cruciate ligament (ACL). Repairs with screw fixation may provide the greatest stability to fracture fragments. The purpose of this study was to evaluate the performance of metal screws for fixation of pediatric tibial eminence avulsion fractures compared to bioabsorbable (polymer) screws. Methods Data for bioabsorbable screws were compiled from a previous phase of the study.* For comparison, six 16-week old bovine knees were dissected, leaving the ACL intact. Tibial eminence avulsion fractures were created using a curved osteotome. These fractures were repaired by a surgeon using metal screws. The repaired knees were then mounted to a servohydraulic materials testing machine at 30 degrees of flexion. After preconditioning, cyclic tensile loads simulating anterior tibial translation were applied to the tibia (5-150N, 1Hz, 200 cycles) then tested to failure. Displacement (mm) and force (N) were recorded for the duration of testing. Gross mechanical stiffness was determined by taking the rate of deformation over the initial loading. Statistics were compared using a one-way ANOVA. (Table) Conclusion Polymer screws have been shown to be difficult to place and prone to breakage. This was reflected in the variable performance of the polymer screws. The primary disadvantage of metal screw fixation is that pediatric patients require implant removal to prevent early physeal arrest. Based upon the data of this study, the metal screws showed less deformation during cyclic testing and more consistent mechanical behavior. Both fixation methods may withstand a maximum force greater than a pediatric ACL would experience during rehabilitation. However, the low initial deformation suggests that the metal screw would better maintain repair integrity.
- Published
- 2005
- Full Text
- View/download PDF
50. Effect of Internal and External Rotation on Strain in the Rotator Cuff
- Author
-
A. Lowry, R. Oka, A. Mahar, and R. Pedowitz
- Subjects
General Medicine ,General Biochemistry, Genetics and Molecular Biology - Published
- 2005
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.