Diffusion-weighted imaging in transient global amnesia exposes the CA1 region of the hippocampus

International Nuclear Information System (INIS)

Lee, Ho Yun; Kim, Jae Hyoung; Weon, Young-Cheol; Youn, Sung Won; Kim, Sung Hyun; Lee, Jung Seok; Kim, Sang Yun

2007-01-01

Transient global amnesia (TGA) is characterized by a sudden onset of anterograde amnesia without alteration of consciousness or personal identity. Interestingly, recent studies have reported a high frequency of small high-signal abnormalities in the hippocampus with diffusion-weighted (DW) imaging, and ischemia has been proposed as an etiology of TGA. We hypothesized that TGA lesions occur preferentially in the CA1 region of the hippocampus, known to be susceptible to ischemia. Over a 30-month period 34 patients with TGA underwent MRI including DW imaging within 4 days of symptom onset. Patients with high-signal abnormalities in the hippocampus on the initial DW images underwent subsequent DW and T2-weighted imaging in the coronal plane to identify the precise lesion locations. Fourteen patients had small (1-3 mm) high-signal abnormalities in the hippocampus unilaterally on DW images. One of these patients had two lesions in one hippocampus and therefore in total 15 lesions were identified: four in the hippocampal head, and 11 in the body. Eleven lesions in ten patients with available coronal images were clearly demonstrated on both coronal DW and T2-weighted images and were localized to the lateral portion of the hippocampus, corresponding to the CA1 region. Lesions associated with TGA were localized exclusively to the lateral portion of the hippocampus corresponding to the CA1 region. This finding supports the ischemic etiology of TGA; however, the pathophysiological mechanism involved requires further study. (orig.)

Referencing handbook: OSCOLA

OpenAIRE

Williams, Helen

2016-01-01

University of Lincoln approved guide to OSCOLA referencing. Providing guidelines on how to reference UK, EU and International primary sources of law and secondary sources. The handbook provides examples and annotated diagrams to help you reference sources in the OSCOLA style.

A Picture is Worth 1,000 Words. The Use of Clinical Images in Electronic Medical Records.

Science.gov (United States)

Ai, Angela C; Maloney, Francine L; Hickman, Thu-Trang; Wilcox, Allison R; Ramelson, Harley; Wright, Adam

2017-07-12

To understand how clinicians utilize image uploading tools in a home grown electronic health records (EHR) system. A content analysis of patient notes containing non-radiological images from the EHR was conducted. Images from 4,000 random notes from July 1, 2009 - June 30, 2010 were reviewed and manually coded. Codes were assigned to four properties of the image: (1) image type, (2) role of image uploader (e.g. MD, NP, PA, RN), (3) practice type (e.g. internal medicine, dermatology, ophthalmology), and (4) image subject. 3,815 images from image-containing notes stored in the EHR were reviewed and manually coded. Of those images, 32.8% were clinical and 66.2% were non-clinical. The most common types of the clinical images were photographs (38.0%), diagrams (19.1%), and scanned documents (14.4%). MDs uploaded 67.9% of clinical images, followed by RNs with 10.2%, and genetic counselors with 6.8%. Dermatology (34.9%), ophthalmology (16.1%), and general surgery (10.8%) uploaded the most clinical images. The content of clinical images referencing body parts varied, with 49.8% of those images focusing on the head and neck region, 15.3% focusing on the thorax, and 13.8% focusing on the lower extremities. The diversity of image types, content, and uploaders within a home grown EHR system reflected the versatility and importance of the image uploading tool. Understanding how users utilize image uploading tools in a clinical setting highlights important considerations for designing better EHR tools and the importance of interoperability between EHR systems and other health technology.

Age Differences in Self-Referencing: Evidence for Common and Distinct Encoding Strategies

Science.gov (United States)

Gutchess, Angela H.; Sokal, Rebecca; Coleman, Jennifer A.; Gotthilf, Gina; Grewal, Lauren; Rosa, Nicole

2014-01-01

Although engagement of medial prefrontal cortex (MPFC) underlies self-referencing of information for younger and older adults, the region has not consistently been implicated across age groups for the encoding of self-referenced information. We sought to determine whether making judgments about others as well as the self influenced findings in the previous study. During an fMRI session, younger and older adults encoded adjectives using only a self-reference task. For items later remembered compared to those later forgotten, both age groups robustly recruited medial prefrontal cortex, indicating common neural regions support encoding across younger and older adults when participants make only self-reference judgments. Focal age differences emerged in regions related to emotional processing and cognitive control, though these differences are more limited than in tasks in which judgments also are made about others. We conclude that making judgments about another person differently affects the ways that younger and older adults make judgments about the self, with results of a follow-up behavioral study supporting this interpretation. PMID:25223905

Referencing handbook: Harvard

OpenAIRE

Elkin, Judith; Ortega, Marishona; Williams, Helen

2016-01-01

University of Lincoln approved guide to Harvard referencing. Providing guidelines on how to reference 75 sources of information. The second edition includes extended guidance on how to reference, all new examples, additional annotated diagrams and an index to help you locate sources.

Empowering Student Learning Through Rubric-Referenced Self-Assessment*

Science.gov (United States)

He, Xiaohua; Canty, Anne

2012-01-01

Purpose: The purpose of this study was to investigate the effect of rubric-referenced self-assessment on performance of anatomy assignments in a group of chiropractic students. Methods: Participants (N = 259) were first-quarter students who were divided into a treatment group (n = 130) and a comparison group (n = 129). The intervention for both groups involved the use of rubrics to complete the first draft of assignments. General feedback was given by the instructor, and then the students had the opportunity to amend the assignments before resubmission (second draft). The treatment group, however, was also asked to perform rubric-referenced self-assessment of their assignments during their second draft. Although the comparison group was also provided with the identical rubrics for the assignments, the students in this group did not perform rubric-referenced self-assessment. Results: The results revealed that the students in the treatment group who used a rubric-referenced self-assessment learning tool received statistically significant higher scores than the comparison group, who did not use this rubric-referenced self-assessment tool. Conclusion: This study suggests that practicing rubric-referenced self-assessment enhances student performance on assignments. However, educators continue to face the challenge of developing practical and useful rubric tools for student self-assessment PMID:22778527

Pediatric imaging in DICER1 syndrome

International Nuclear Information System (INIS)

Bueno, Marta Tijerin; Martinez-Rios, Claudia; Ahyad, Rayan A.; Greer, Mary-Louise C.; Puente Gregorio, Alejandro de la; Villani, Anita; Malkin, David; Druker, Harriet; Van Engelen, Kalene; Gallinger, Bailey; Aronoff, Laura; Grant, Ronald

2017-01-01

DICER1 syndrome, arising from a mutation in the DICER1 gene mapped to chromosome 14q32, is associated with an increased risk of a range of benign and malignant neoplasms. To determine the spectrum of abnormalities and imaging characteristics in patients with DICER1 syndrome at a tertiary pediatric hospital. This retrospective analysis evaluated imaging in patients ≤18 years with DICER1 germline variants between January 2004 and July 2016. An imaging database search including keywords pleuropulmonary blastoma, cystic nephroma, pineoblastoma, embryonal rhabdomyosarcoma, ovarian sex cord-stromal tumor, ovarian Sertoli-Leydig cell tumor and DICER1 syndrome, was cross-referenced against the institutional Cancer Genetics Program database, excluding patients with negative/unknown DICER1 gene testing. Sixteen patients were included (12 females; mean age at presentation: 4.2 years, range: 14 days to 17 years), with surveillance imaging encompassing the following modalities: chest X-ray and CT; abdominal, pelvic and neck US; and brain and whole-body MRI. Malignant lesions (68.8% of patients) included pleuropulmonary blastoma (5), pineoblastoma (3), ovarian Sertoli-Leydig cell tumor (1), embryonal rhabdomyosarcoma (1) and renal sarcoma (1); benign lesions (37.5% of patients) included thyroid cysts (2), thyroid nodules (2), cystic nephroma (2), renal cysts (1) and pineal cyst (1). A common lesional appearance observed across modalities and organs was defined as the ''cracked windshield'' sign. The spectrum of DICER1-related tumors and the young age at presentation suggest early surveillance of at-risk patients is critical, while minimizing exposure to ionizing radiation. (orig.)

Pediatric imaging in DICER1 syndrome

Energy Technology Data Exchange (ETDEWEB)

Bueno, Marta Tijerin; Martinez-Rios, Claudia; Ahyad, Rayan A.; Greer, Mary-Louise C. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, Ontario (Canada); University of Toronto, Department of Medical Imaging, Toronto, Ontario (Canada); Puente Gregorio, Alejandro de la [Hospital Son Espases, Radiotherapy Department, Palma de Mallorca (Spain); Villani, Anita; Malkin, David [University of Toronto, Department of Pediatrics, Toronto, Ontario (Canada); The Hospital for Sick Children, Division of Hematology/Oncology, Toronto, Ontario (Canada); The Hospital for Sick Children, Genetics and Genomic Biology Program, Toronto, Ontario (Canada); Druker, Harriet [The Hospital for Sick Children, Division of Hematology/Oncology, Toronto, Ontario (Canada); The Hospital for Sick Children, Department of Genetic Counselling, Toronto, Ontario (Canada); The Hospital for Sick Children, Department of Molecular Genetics, Toronto, Ontario (Canada); Van Engelen, Kalene [The Hospital for Sick Children, Genetics and Genomic Biology Program, Toronto, Ontario (Canada); Gallinger, Bailey [The Hospital for Sick Children, Genetics and Genomic Biology Program, Toronto, Ontario (Canada); The Hospital for Sick Children, Department of Genetic Counselling, Toronto, Ontario (Canada); The Hospital for Sick Children, Department of Molecular Genetics, Toronto, Ontario (Canada); Aronoff, Laura [The Hospital for Sick Children, Division of Hematology/Oncology, Toronto, Ontario (Canada); Grant, Ronald [University of Toronto, Department of Pediatrics, Toronto, Ontario (Canada); The Hospital for Sick Children, Division of Hematology/Oncology, Toronto, Ontario (Canada)

2017-09-15

DICER1 syndrome, arising from a mutation in the DICER1 gene mapped to chromosome 14q32, is associated with an increased risk of a range of benign and malignant neoplasms. To determine the spectrum of abnormalities and imaging characteristics in patients with DICER1 syndrome at a tertiary pediatric hospital. This retrospective analysis evaluated imaging in patients ≤18 years with DICER1 germline variants between January 2004 and July 2016. An imaging database search including keywords pleuropulmonary blastoma, cystic nephroma, pineoblastoma, embryonal rhabdomyosarcoma, ovarian sex cord-stromal tumor, ovarian Sertoli-Leydig cell tumor and DICER1 syndrome, was cross-referenced against the institutional Cancer Genetics Program database, excluding patients with negative/unknown DICER1 gene testing. Sixteen patients were included (12 females; mean age at presentation: 4.2 years, range: 14 days to 17 years), with surveillance imaging encompassing the following modalities: chest X-ray and CT; abdominal, pelvic and neck US; and brain and whole-body MRI. Malignant lesions (68.8% of patients) included pleuropulmonary blastoma (5), pineoblastoma (3), ovarian Sertoli-Leydig cell tumor (1), embryonal rhabdomyosarcoma (1) and renal sarcoma (1); benign lesions (37.5% of patients) included thyroid cysts (2), thyroid nodules (2), cystic nephroma (2), renal cysts (1) and pineal cyst (1). A common lesional appearance observed across modalities and organs was defined as the ''cracked windshield'' sign. The spectrum of DICER1-related tumors and the young age at presentation suggest early surveillance of at-risk patients is critical, while minimizing exposure to ionizing radiation. (orig.)

Collaborative Referencing between Individuals with Aphasia and Routine Communication Partners.

Science.gov (United States)

Hengst, Julie A.

2003-01-01

This study examined how four adults with aphasia collaborated with routine communication partners. Overall, these pairs completed the referencing task trials with accuracy and displayed referencing processes that conformed to the collaborative referencing model of communication. However, the pairs also used diverse verbal and nonverbal resources,…

Identification and two-photon imaging of oligodendrocyte in CA1 region of hippocampal slices

International Nuclear Information System (INIS)

Zhou Wei; Ge Wooping; Zeng Shaoqun; Duan Shumin; Luo Qingming

2007-01-01

Oligodendrocyte (OL) plays a critical role in myelination and axon maintenance in central nervous system. Recent studies show that OL can also express NMDA receptors in development and pathological situations in white matter. There is still lack of studies about OL properties and function in gray matter of brain. Here we reported that some glial cells in CA1 region of rat hippocampal slices (P15-23) had distinct electrophysiological characteristics from the other glia cells in this region, while they displayed uniform properties with OL from white matter in previous report; therefore, they were considered as OL in hippocampus. By loading dye in recording pipette and imaging with two-photon laser scanning microscopy, we acquired the high spatial resolution, three-dimension images of these special cells in live slices. The OL in hippocampus shows a complex process-bearing shape and the distribution of several processes is parallel to Schaffer fiber in CA1 region. When stimulating Schaffer fiber, OL displays a long duration depolarization mediated by inward rectifier potassium channel. This suggested that the OL in CA1 region could sense the neuronal activity and contribute to potassium clearance

Region segmentation along image sequence

International Nuclear Information System (INIS)

Monchal, L.; Aubry, P.

1995-01-01

A method to extract regions in sequence of images is proposed. Regions are not matched from one image to the following one. The result of a region segmentation is used as an initialization to segment the following and image to track the region along the sequence. The image sequence is exploited as a spatio-temporal event. (authors). 12 refs., 8 figs

Digital Hydrologic Networks Supporting Applications Related to Spatially Referenced Regression Modeling

Science.gov (United States)

Brakebill, J.W.; Wolock, D.M.; Terziotti, S.E.

2011-01-01

Digital hydrologic networks depicting surface-water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the movement of water and associated constituents throughout the landscape. Digital hydrologic networks have evolved from derivatives of mapping products to detailed, interconnected, spatially referenced networks of water pathways, drainage areas, and stream and watershed characteristics. These properties are important because they enhance the ability to spatially evaluate factors that affect the sources and transport of water-quality constituents at various scales. SPAtially Referenced Regressions On Watershed attributes (SPARROW), a process-based/statistical model, relies on a digital hydrologic network in order to establish relations between quantities of monitored contaminant flux, contaminant sources, and the associated physical characteristics affecting contaminant transport. Digital hydrologic networks modified from the River Reach File (RF1) and National Hydrography Dataset (NHD) geospatial datasets provided frameworks for SPARROW in six regions of the conterminous United States. In addition, characteristics of the modified RF1 were used to update estimates of mean-annual streamflow. This produced more current flow estimates for use in SPARROW modeling. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

MR imaging of hematopoietic regions in bone marrow of aplastic anemia. Diagnostic usefulness of opposed phase T1-weighted images

Energy Technology Data Exchange (ETDEWEB)

Amano, Yasuo; Tanabe, Yoshihiro; Amano, Maki; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

1996-01-01

The signal intensity of hematopoietic regions in the marrow of aplastic anemia were investigated on opposed phase T1-weighted images (op-T1WI) with a 0.5-Tesla MR unit. Hematopoietic regions were classified into two groups: low intensity hematopoietic areas (LH) isointense to normal marrow and high intensity hematopoietic regions (HH) with higher intensity than normal marrow on op-T1WI. The signal intensity of LH was significantly lower than that of HH on STIR. LH converted into HH with improvement of laboratory data after therapy, whereas HH decreased with impairment of data. HH were hyperintense to cerebrospinal fluid on op-T1WI. These results indicated that the signal intensity of hematopoietic regions on op-T1WI reflected the cellularity in these regions and that aplastic anemia included hypercellular regions relative to normal marrow. (author).

Social referencing and cat-human communication.

Science.gov (United States)

Merola, I; Lazzaroni, M; Marshall-Pescini, S; Prato-Previde, E

2015-05-01

Cats' (Felis catus) communicative behaviour towards humans was explored using a social referencing paradigm in the presence of a potentially frightening object. One group of cats observed their owner delivering a positive emotional message, whereas another group received a negative emotional message. The aim was to evaluate whether cats use the emotional information provided by their owners about a novel/unfamiliar object to guide their own behaviour towards it. We assessed the presence of social referencing, in terms of referential looking towards the owner (defined as looking to the owner immediately before or after looking at the object), the behavioural regulation based on the owner's emotional (positive vs negative) message (vocal and facial), and the observational conditioning following the owner's actions towards the object. Most cats (79 %) exhibited referential looking between the owner and the object, and also to some extent changed their behaviour in line with the emotional message given by the owner. Results are discussed in relation to social referencing in other species (dogs in particular) and cats' social organization and domestication history.

Functional requirements for a comprehensive transportation location referencing system

Science.gov (United States)

2000-06-01

Transportation agencies manage data that is referenced in one, two, three, and four dimensions. Location referencing system (LRS) data models vary across transportation agencies and often within organizations as well. This has resulted in failed atte...

Image registration via optimization over disjoint image regions

Science.gov (United States)

Pitts, Todd; Hathaway, Simon; Karelitz, David B.; Sandusky, John; Laine, Mark Richard

2018-02-06

Technologies pertaining to registering a target image with a base image are described. In a general embodiment, the base image is selected from a set of images, and the target image is an image in the set of images that is to be registered to the base image. A set of disjoint regions of the target image is selected, and a transform to be applied to the target image is computed based on the optimization of a metric over the selected set of disjoint regions. The transform is applied to the target image so as to register the target image with the base image.

Short-Cut Estimators of Criterion-Referenced Test Consistency.

Science.gov (United States)

Brown, James Dean

1990-01-01

Presents simplified methods for deriving estimates of the consistency of criterion-referenced, English-as-a-Second-Language tests, including (1) the threshold loss agreement approach using agreement or kappa coefficients, (2) the squared-error loss agreement approach using the phi(lambda) dependability approach, and (3) the domain score…

Watershed-based Image Segmentation with Region Merging and Edge Detection

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

The clustering technique is used to examine each pixel in the image which assigned to one of the clusters depending on the minimum distance to obtain primary classified image into different intensity regions. A watershed transformation technique is then employes. This includes: gradient of the classified image, dividing the image into markers, checking the Marker Image to see if it has zero points (watershed lines). The watershed lines are then deleted in the Marker Image created by watershed algorithm. A Region Adjacency Graph (RAG) and Region Adjacency Boundary (RAB) are created between two regions from Marker Image. Finally region merging is done according to region average intensity and two edge strengths (T1, T2). The approach of the authors is tested on remote sensing and brain MR medical images. The final segmentation result is one closed boundary per actual region in the image.

Rate of self-referencing int he journal Radiologia: An indicator of quality

International Nuclear Information System (INIS)

Miguel, A.; Marti-Bonmati, L.

2000-01-01

Self-referencing, defined as the number of times articles published in a scientific journal cite previous articles printed in the same journal, is an important indicator of quality. Our purpose was to analyze the rate of self-referencing in the journal Radiologia. All the articles published in Radiologia from 1994 to 1998 were analyzed to determine the index of references to Radiologia (IRR) and the index of articles that refer to Radiologia (IAR). these indices were also calculated for European Radiology (index of references to European Radiologia (IRER) and index or articles referring to European Radiology (IAER), a journal that is listed in the Index Medicus, for the year 1998. Between 1994 and 1998, the IRR ranged from 1.5% to 1,9%. In 1998, it was 1.8% while the IRER was only 0.9%, a difference that was statistically significant (p=0.02). In that same year, the IAR was also higher than the IAER (2.3% versus 1.6%). The rate of self-referencing in Radiologia is higher than that of European Radiology, a journal that is included in the Index Medicus and its Medline database. (Author) 13 refs

Dynamic MR imaging of the sellar region

International Nuclear Information System (INIS)

Takahashi, M.; Sakamoto, Y.; Korogi, Y.; Nishimura, R.; Yoshizumi, K.; Ushio, Y.

1990-01-01

This paper reports on sequential and differential enhancement of the normal and abnormal structures of the sellar regions were evaluated with dynamic MR imaging for the diagnosis of sellar and parasellar tumors. Dynamic MR imaging was performed on a 1.5-T superconductive unit, with rapid injection of Gd-DTPA (0.1 mmol/kg body weight) followed by serial spin-echo (TR 220/TE 15 msec) images of the sellar region for 3-5 minutes. The first structures visualized were the cavernous sinus, infundibulum, and posterior pituitary lobe within 30 seconds, followed by enhancement of the anterior pituitary lobe near the infundibulum in 50 seconds and the peripheral portion of the anterior pituitary lobe in 80 seconds

User Defined Geo-referenced Information

DEFF Research Database (Denmark)

Konstantas, Dimitri; Villalba, Alfredo; di Marzo Serugendo, Giovanna

2009-01-01

. In this paper we present two novel mobile and wireless collaborative services and concepts, the Hovering Information, a mobile, geo-referenced content information management system, and the QoS Information service, providing user observed end-to-end infrastructure geo-related QoS information....

Helping me, helping you: self-referencing and gender roles in donor advertising.

Science.gov (United States)

Hupfer, M E

2006-06-01

Donor advertising typically emphasizes altruism, but an appeal to individual self-interest may be more effective in heightening blood donation intentions among youthful nondonors. A total of 292 undergraduate business students at a Canadian university provided complete data in response to a between-subjects full-factorial advertising experiment with sex, self-referencing, and message strategy factors. Self-referencing, or mental processing that links information to the self-concept, was elicited at either a low or moderate level, whereas the message strategy was either agentic (donate blood because you may need it yourself) or communal (donate blood because someone close to you may need it). Dependent variables included identification with the ad, donation intentions, and a discrimination measure of recognition memory. A three-way interaction among sex, self-referencing level (low or moderate), and message (agentic or communal) was found. Two-way self-referencing by message graphs of donation intentions and ad identification showed a parallel structure for males in that their responses were generally more favorable when self-referencing was at a moderate level, regardless of the message type. Among women, however, crossover interactions between the level of self-referencing and the message type (agentic vs. communal) were observed, such that the message's effect differed with the level of self-referencing. For both men and women, the agentic message was more effective than communal ad copy when a moderate level of self-referencing was achieved. Collection agencies should consider appealing to young nondonors by suggesting that they give blood to make it available for themselves if required.

Academic Practice, APA Referencing Style:guidelines for staff and students

OpenAIRE

Nielsen, Sandro; Heine, Carmen

2017-01-01

Vejledning i at undgå plagiering ved at følge de normer, der gælder for good academic practice. Dette indebærer at man angiver kilder korrekt, og når det er nødvendigt, og at man har en korrekt udformet fortegnelse over referencer. Vejledningen indeholder konkrete eksempler på korrekt kildeangivelse og referencer i henhold til APA referencing system.Vejledning i at undgå plagiering ved at følge de normer, der gælder for good academic practice. Dette indebærer at man angiver kilder korrekt, og...

Referenciamento regional em saúde: estudo comparado de cinco casos no Estado de São Paulo, Brasil Management practices of regional referencing: a comparative study of five cases in the State of São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Sonia Isoyama Venancio

2011-09-01

Full Text Available OBJETIVO: avaliar práticas gestoras de referenciamento regional no Estado de São Paulo, identificando as principais dificuldades encontradas nos processos de pactuação com vistas à integralidade da atenção. Metodologia; foram selecionadas 5 Regiões (Campinas- CPN, Piracicaba-PRC, Mogi das Cruzes-MC, São José do Rio Preto-SJRP e São José dos Campos-SJC nas quais foram analisados: indicadores de 4 linhas de cuidado (Hipertensão Arterial-HA e Diabetes Mellitus-DM, Saúde Mental, Bucal e da Mulher; os instrumentos de referenciamento operantes e a percepção dos gestores regionais e municipais sobre este processo. RESULTADOS: o desempenho dos gestores no tocante ao alcance da universalidade e integralidade da atenção foi analisado através de 11 indicadores, resultando em um escore com variação de 0 a 5. A classificação das regiões foi: SJRP (4,55; CPN (2,91; SJC (2,27; PRC (2,27 e MC (1,91. A análise das entrevistas com gestores revelou que os mecanismos formais de referenciamento são insuficientes, bem como os instrumentos para o seu acompanhamento; nas regiões metropolitanas parece haver maior dificuldade para pactuação das referências; o fortalecimento dos espaços de negociação entre os gestores foi apontado como um fator facilitador do processo.OBJECTIVE: To evaluate management practices of regional referencing in the State of São Paulo, identifying the main difficulties in the process of agreement between health managers to achieve integrate health care. Methodology: 5 regions were selected (CPN-Campinas, Piracicaba-PRC, MC-Mogi das Cruzes, São José do Rio Preto-SJRP and Sao Jose dos Campos-SJC in which were analyzed: indicators of 4 lines of care (Hypertension-HA and Diabetes Mellitus-DM, Mental Health, Oral and Women, the working tools of referencing and perceptions of regional and municipal managers on the process. RESULTS: the performance of managers regarding the scope of the universality and

A better norm-referenced grading using the standard deviation criterion.

Science.gov (United States)

Chan, Wing-shing

2014-01-01

The commonly used norm-referenced grading assigns grades to rank-ordered students in fixed percentiles. It has the disadvantage of ignoring the actual distance of scores among students. A simple norm-referenced grading via standard deviation is suggested for routine educational grading. The number of standard deviation of a student's score from the class mean was used as the common yardstick to measure achievement level. Cumulative probability of a normal distribution was referenced to help decide the amount of students included within a grade. RESULTS of the foremost 12 students from a medical examination were used for illustrating this grading method. Grading by standard deviation seemed to produce better cutoffs in allocating an appropriate grade to students more according to their differential achievements and had less chance in creating arbitrary cutoffs in between two similarly scored students than grading by fixed percentile. Grading by standard deviation has more advantages and is more flexible than grading by fixed percentile for norm-referenced grading.

Benchmark referencing of neutron dosimetry measurements

International Nuclear Information System (INIS)

Eisenhauer, C.M.; Grundl, J.A.; Gilliam, D.M.; McGarry, E.D.; Spiegel, V.

1980-01-01

The concept of benchmark referencing involves interpretation of dosimetry measurements in applied neutron fields in terms of similar measurements in benchmark fields whose neutron spectra and intensity are well known. The main advantage of benchmark referencing is that it minimizes or eliminates many types of experimental uncertainties such as those associated with absolute detection efficiencies and cross sections. In this paper we consider the cavity external to the pressure vessel of a power reactor as an example of an applied field. The pressure vessel cavity is an accessible location for exploratory dosimetry measurements aimed at understanding embrittlement of pressure vessel steel. Comparisons with calculated predictions of neutron fluence and spectra in the cavity provide a valuable check of the computational methods used to estimate pressure vessel safety margins for pressure vessel lifetimes

R@P: developing and promoting the Referencing@Portsmouth service

OpenAIRE

Matthews, J.; Gwyer, Roisin; Jones, Linda; Worden, Anne

2009-01-01

The library at the University of Portsmouth (UoP) has for some years been providing advice on referencing across the institution, either at enquiry desks or through subject/faculty librarians.In addition, annually updated short guidesto Vancouver and Harvard (American Psychological Association variant) were produced by thelibrary, and distributed to new students in their thousands. This sufficed for a time but in thelast three or four years the number of referencing enquiries being fielded by...

AUTOMATED CLASSIFICATION AND SEGREGATION OF BRAIN MRI IMAGES INTO IMAGES CAPTURED WITH RESPECT TO VENTRICULAR REGION AND EYE-BALL REGION

Directory of Open Access Journals (Sweden)

C. Arunkumar

2014-05-01

Full Text Available Magnetic Resonance Imaging (MRI images of the brain are used for detection of various brain diseases including tumor. In such cases, classification of MRI images captured with respect to ventricular and eye ball regions helps in automated location and classification of such diseases. The methods employed in the paper can segregate the given MRI images of brain into images of brain captured with respect to ventricular region and images of brain captured with respect to eye ball region. First, the given MRI image of brain is segmented using Particle Swarm Optimization (PSO algorithm, which is an optimized algorithm for MRI image segmentation. The algorithm proposed in the paper is then applied on the segmented image. The algorithm detects whether the image consist of a ventricular region or an eye ball region and classifies it accordingly.

Unemployment estimation: Spatial point referenced methods and models

KAUST Repository

Pereira, Soraia

2017-06-26

Portuguese Labor force survey, from 4th quarter of 2014 onwards, started geo-referencing the sampling units, namely the dwellings in which the surveys are carried. This opens new possibilities in analysing and estimating unemployment and its spatial distribution across any region. The labor force survey choose, according to an preestablished sampling criteria, a certain number of dwellings across the nation and survey the number of unemployed in these dwellings. Based on this survey, the National Statistical Institute of Portugal presently uses direct estimation methods to estimate the national unemployment figures. Recently, there has been increased interest in estimating these figures in smaller areas. Direct estimation methods, due to reduced sampling sizes in small areas, tend to produce fairly large sampling variations therefore model based methods, which tend to

First light for GRAVITY: Phase referencing optical interferometry for the Very Large Telescope Interferometer

Science.gov (United States)

Gravity Collaboration; Abuter, R.; Accardo, M.; Amorim, A.; Anugu, N.; Ávila, G.; Azouaoui, N.; Benisty, M.; Berger, J. P.; Blind, N.; Bonnet, H.; Bourget, P.; Brandner, W.; Brast, R.; Buron, A.; Burtscher, L.; Cassaing, F.; Chapron, F.; Choquet, É.; Clénet, Y.; Collin, C.; Coudé Du Foresto, V.; de Wit, W.; de Zeeuw, P. T.; Deen, C.; Delplancke-Ströbele, F.; Dembet, R.; Derie, F.; Dexter, J.; Duvert, G.; Ebert, M.; Eckart, A.; Eisenhauer, F.; Esselborn, M.; Fédou, P.; Finger, G.; Garcia, P.; Garcia Dabo, C. E.; Garcia Lopez, R.; Gendron, E.; Genzel, R.; Gillessen, S.; Gonte, F.; Gordo, P.; Grould, M.; Grözinger, U.; Guieu, S.; Haguenauer, P.; Hans, O.; Haubois, X.; Haug, M.; Haussmann, F.; Henning, Th.; Hippler, S.; Horrobin, M.; Huber, A.; Hubert, Z.; Hubin, N.; Hummel, C. A.; Jakob, G.; Janssen, A.; Jochum, L.; Jocou, L.; Kaufer, A.; Kellner, S.; Kendrew, S.; Kern, L.; Kervella, P.; Kiekebusch, M.; Klein, R.; Kok, Y.; Kolb, J.; Kulas, M.; Lacour, S.; Lapeyrère, V.; Lazareff, B.; Le Bouquin, J.-B.; Lèna, P.; Lenzen, R.; Lévêque, S.; Lippa, M.; Magnard, Y.; Mehrgan, L.; Mellein, M.; Mérand, A.; Moreno-Ventas, J.; Moulin, T.; Müller, E.; Müller, F.; Neumann, U.; Oberti, S.; Ott, T.; Pallanca, L.; Panduro, J.; Pasquini, L.; Paumard, T.; Percheron, I.; Perraut, K.; Perrin, G.; Pflüger, A.; Pfuhl, O.; Phan Duc, T.; Plewa, P. M.; Popovic, D.; Rabien, S.; Ramírez, A.; Ramos, J.; Rau, C.; Riquelme, M.; Rohloff, R.-R.; Rousset, G.; Sanchez-Bermudez, J.; Scheithauer, S.; Schöller, M.; Schuhler, N.; Spyromilio, J.; Straubmeier, C.; Sturm, E.; Suarez, M.; Tristram, K. R. W.; Ventura, N.; Vincent, F.; Waisberg, I.; Wank, I.; Weber, J.; Wieprecht, E.; Wiest, M.; Wiezorrek, E.; Wittkowski, M.; Woillez, J.; Wolff, B.; Yazici, S.; Ziegler, D.; Zins, G.

2017-06-01

GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130 m diameter angular resolution and a collecting area of 200 m2. The instrument comprises fiber fed integrated optics beam combination, high resolution spectroscopy, built-in beam analysis and control, near-infrared wavefront sensing, phase-tracking, dual-beam operation, and laser metrology. GRAVITY opens up to optical/infrared interferometry the techniques of phase referenced imaging and narrow angle astrometry, in many aspects following the concepts of radio interferometry. This article gives an overview of GRAVITY and reports on the performance and the first astronomical observations during commissioning in 2015/16. We demonstrate phase-tracking on stars as faint as mK ≈ 10 mag, phase-referenced interferometry of objects fainter than mK ≈ 15 mag with a limiting magnitude of mK ≈ 17 mag, minute long coherent integrations, a visibility accuracy of better than 0.25%, and spectro-differential phase and closure phase accuracy better than 0.5°, corresponding to a differential astrometric precision of better than ten microarcseconds (μas). The dual-beam astrometry, measuring the phase difference of two objects with laser metrology, is still under commissioning. First observations show residuals as low as 50 μas when following objects over several months. We illustrate the instrument performance with the observations of archetypical objects for the different instrument modes. Examples include the Galactic center supermassive black hole and its fast orbiting star S2 for phase referenced dual-beam observations and infrared wavefront sensing, the high mass X-ray binary BP Cru and the active galactic nucleus of PDS 456 for a few μas spectro-differential astrometry, the T Tauri star S CrA for a spectro-differential visibility analysis, ξ Tel and 24 Cap for high accuracy visibility observations

Multi region based image retrieval system

Indian Academy of Sciences (India)

data mining, information theory, statistics and psychology. ∗ .... ground complication and independent of image size and orientation (Zhang 2007). ..... Figure 2. Significant regions: (a) the input image, (b) the primary significant region, (c) the ...

A study of prostate delineation referenced against a gold standard created from the visible human data

International Nuclear Information System (INIS)

Gao Zhanrong; Wilkins, David; Eapen, Libni; Morash, Christopher; Wassef, Youssef; Gerig, Lee

2007-01-01

Purpose: To measure inter- and intra-observer variation and systematic error in CT based prostate delineation, where individual delineations are referenced against a gold standard produced from photographic anatomical images from the Visible Human Project (VHP). Materials and methods: The CT and anatomical images of the VHP male form the basic data set for this study. The gold standard was established based on 1 mm thick anatomical photographic images. These were registered against the 3 mm thick CT images that were used for target delineation. A total of 120 organ delineations were performed by six radiation oncologists. Results: The physician delineated prostate volume was on average 30% larger than the 'true' prostate volume, but on average included only 84% of the gold standard volume. Our study found a systematic delineation error such that posterior portions of the prostate were always missed while anteriorly some normal tissue was always defined as target. Conclusions: Our data suggest that radiation oncologists are more concerned with the unintentional inclusion of rectal tissue than they are in missing prostate volume. In contrast, they are likely to overextend the anterior boundary of the prostate to encompass normal tissue such as the bladder

Constraint-Referenced Analytics of Algebra Learning

Science.gov (United States)

Sutherland, Scot M.; White, Tobin F.

2016-01-01

The development of the constraint-referenced analytics tool for monitoring algebra learning activities presented here came from the desire to firstly, take a more quantitative look at student responses in collaborative algebra activities, and secondly, to situate those activities in a more traditional introductory algebra setting focusing on…

From Pixels to Region: A Salient Region Detection Algorithm for Location-Quantification Image

Directory of Open Access Journals (Sweden)

Mengmeng Zhang

2014-01-01

Full Text Available Image saliency detection has become increasingly important with the development of intelligent identification and machine vision technology. This process is essential for many image processing algorithms such as image retrieval, image segmentation, image recognition, and adaptive image compression. We propose a salient region detection algorithm for full-resolution images. This algorithm analyzes the randomness and correlation of image pixels and pixel-to-region saliency computation mechanism. The algorithm first obtains points with more saliency probability by using the improved smallest univalue segment assimilating nucleus operator. It then reconstructs the entire saliency region detection by taking these points as reference and combining them with image spatial color distribution, as well as regional and global contrasts. The results for subjective and objective image saliency detection show that the proposed algorithm exhibits outstanding performance in terms of technology indices such as precision and recall rates.

Selecting Items for Criterion-Referenced Tests.

Science.gov (United States)

Mellenbergh, Gideon J.; van der Linden, Wim J.

1982-01-01

Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)

Does contingency in adults' responding influence 12-month-old infants' social referencing?

Science.gov (United States)

Stenberg, Gunilla

2017-11-01

In two experiments we examined the influence of contingent versus non-contingent responding on infant social referencing behavior. EXPERIMENT 1: Forty 12-month-old infants were exposed to an ambiguous toy in a social referencing situation. In one condition an unfamiliar adult who in a previous play situation had responded contingently to the infant's looks gave the infant positive information about the toy. In the other condition an unfamiliar adult who previously had not responded contingently delivered the positive information. EXPERIMENT 2: Forty-eight 12-month-old infants participated in Experiment 2. In this experiment it was examined whether the familiarity of the adult influences infants' reactions to contingency in responding. In one condition a parent who previously had responded contingently to the infant's looks provided positive information about the ambiguous toy, and in the other condition a parent who previously had not responded contingently provided the positive information. The infants looked more at the contingent experimenter in Experimenter 1, and also played more with the toy after receiving positive information from the contingent experimenter. No differences in looking at the parent and in playing with the toy were found in Experiment 2. The results indicate that contingency in responding, as well as the familiarity of the adult, influence infants' social referencing behavior. Copyright © 2017 Elsevier Inc. All rights reserved.

Classification of hematopoietic regions in out-of-phase T1-weighted images. A quantitative comparison study with T1-weighted and STIR images

International Nuclear Information System (INIS)

Amano, Yasuo; Amano, Maki; Kijima, Tetsuji; Kumazaki, Tatsuo

1995-01-01

The hematopoietic regions were classified into two groups on the basis of out-of-phase T 1 -weighted images (op-TlWI): regions with lower intensity than that of muscle (LH) and regions with intensity equal to or higher than that of muscle (HH). We quantitatively evaluated the differences in signal intensity between LH and HH in order to examine this classification. Forty-two hematopoietic areas in aplastic anemia were classified into two groups of 23 LH and 19 HH. The signal ratios of hematopoietic areas to muscle on TlWI and STIR were calculated, and the differences between LH and HH were statistically evaluated. The signal ratios of LH were significantly higher on TlWI and lower on STIR than those of HH (unpaired t-test, p<0.05). This result indicated that LH consisted of more hypocellular marrow than HH. Op-TlWI were useful in differentiating between LH and HH and defining the degree of hematopoiesis in aplastic anemia. (author)

Social referencing in dog-owner dyads?

Science.gov (United States)

Merola, I; Prato-Previde, E; Marshall-Pescini, S

2012-03-01

Social referencing is the seeking of information from another individual to form one's own understanding and guide action. In this study, adult dogs were tested in a social referencing paradigm involving their owner and a potentially scary object. Dogs received either a positive or negative message from the owner. The aim was to evaluate the presence of referential looking to the owner, behavioural regulation based on the owner's (vocal and facial) emotional message and observational conditioning following the owner's actions towards the object. Most dogs (83%) looked referentially to the owner after looking at the strange object, thus they appear to seek information about the environment from the human, but little differences were found between dogs in the positive and negative groups as regards behavioural regulation: possible explanations for this are discussed. Finally, a strong effect of observational conditioning was found with dogs in the positive group moving closer to the fan and dogs in the negative group moving away, both mirroring their owner's behaviour. Results are discussed in relation to studies on human-dog communication, attachment and social learning.

Generating region proposals for histopathological whole slide image retrieval.

Science.gov (United States)

Ma, Yibing; Jiang, Zhiguo; Zhang, Haopeng; Xie, Fengying; Zheng, Yushan; Shi, Huaqiang; Zhao, Yu; Shi, Jun

2018-06-01

Content-based image retrieval is an effective method for histopathological image analysis. However, given a database of huge whole slide images (WSIs), acquiring appropriate region-of-interests (ROIs) for training is significant and difficult. Moreover, histopathological images can only be annotated by pathologists, resulting in the lack of labeling information. Therefore, it is an important and challenging task to generate ROIs from WSI and retrieve image with few labels. This paper presents a novel unsupervised region proposing method for histopathological WSI based on Selective Search. Specifically, the WSI is over-segmented into regions which are hierarchically merged until the WSI becomes a single region. Nucleus-oriented similarity measures for region mergence and Nucleus-Cytoplasm color space for histopathological image are specially defined to generate accurate region proposals. Additionally, we propose a new semi-supervised hashing method for image retrieval. The semantic features of images are extracted with Latent Dirichlet Allocation and transformed into binary hashing codes with Supervised Hashing. The methods are tested on a large-scale multi-class database of breast histopathological WSIs. The results demonstrate that for one WSI, our region proposing method can generate 7.3 thousand contoured regions which fit well with 95.8% of the ROIs annotated by pathologists. The proposed hashing method can retrieve a query image among 136 thousand images in 0.29 s and reach precision of 91% with only 10% of images labeled. The unsupervised region proposing method can generate regions as predictions of lesions in histopathological WSI. The region proposals can also serve as the training samples to train machine-learning models for image retrieval. The proposed hashing method can achieve fast and precise image retrieval with small amount of labels. Furthermore, the proposed methods can be potentially applied in online computer-aided-diagnosis systems. Copyright

Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

Science.gov (United States)

Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

1979-01-01

The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

Improving image segmentation by learning region affinities

Energy Technology Data Exchange (ETDEWEB)

Prasad, Lakshman [Los Alamos National Laboratory; Yang, Xingwei [TEMPLE UNIV.; Latecki, Longin J [TEMPLE UNIV.

2010-11-03

We utilize the context information of other regions in hierarchical image segmentation to learn new regions affinities. It is well known that a single choice of quantization of an image space is highly unlikely to be a common optimal quantization level for all categories. Each level of quantization has its own benefits. Therefore, we utilize the hierarchical information among different quantizations as well as spatial proximity of their regions. The proposed affinity learning takes into account higher order relations among image regions, both local and long range relations, making it robust to instabilities and errors of the original, pairwise region affinities. Once the learnt affinities are obtained, we use a standard image segmentation algorithm to get the final segmentation. Moreover, the learnt affinities can be naturally unutilized in interactive segmentation. Experimental results on Berkeley Segmentation Dataset and MSRC Object Recognition Dataset are comparable and in some aspects better than the state-of-art methods.

Diagnostic Performance of Three Phase Bone Scan for Complex Regional Pain Syndrome Type 1 with Optimally Modified Image Criteria

Energy Technology Data Exchange (ETDEWEB)

Kwon, Hyun Woo; Paeng, Jin Chul; Nahm, Francins Sahngun; Kim, Seog Gyun; Zehra, Tanzeel; Oh, So Won; Lee, Hyo Sang; Kang, Keon Wook; Chung, June Key; Lee, Myung Chul; Lee, Dong Soo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

2011-12-15

Although the three phase bone scan (TBPS) is one of the widely used imaging studies for diagnosing complex regional pain syndrome type 1 (CRPS 1), there is some controversy regarding the TPBS image criteria for CRPS 1. In this study, we modified the image criteria using image pattern and quantitative analysis in the patients diagnosed using the most recent consensus clinical diagnostic criteria. The study included 140 patients with suspected CRPS 1 (CRPS 1, n=79; non CRPS, n=61; mean age 39{+-}15 years) who underwent TPBS. The clinical diagnostic criteria for CRPS 1 revised by the Budapest consensus group were used for confirmative diagnosis. Patients were classified according to flow/pool and delayed uptake (DU) image patterns, and the time interval between the initiating event and TPBS (TI{sup eventscan)}. Quantitative analysis for lesion to contralateral ratio (LCR) was performed. Modified TPBS image criteria were created and evaluated for optimal diagnostic performance. Both increased and decreased periarticular DU were significant image findings for CRPS 1 (CRPS 1 positive rate=73% in the increased DU group, 75% in the decreased DU group). The TI{sup eventscand}id not differ significantly between the different image pattern groups. Quantitative analysis revealed an LCR of 1.43 was the optimal cutoff value for CRPS 1 and diagnostic performance was significantly improved in the increased DU group (area under the curve=0.732). Given the modified image criteria, the sensitivity and specificity of TPBS for diagnosing CRPS 1 were 80% and 72%, respectively. Optimally modified TPBS image criteria for CRPS 1 were suggested using image pattern and quantitative analysis. With the criteria, TPBS is an effective imaging study for CRPS 1 even with the most recent consensus clinical diagnostic criteria.

Diagnostic Performance of Three Phase Bone Scan for Complex Regional Pain Syndrome Type 1 with Optimally Modified Image Criteria

International Nuclear Information System (INIS)

Kwon, Hyun Woo; Paeng, Jin Chul; Nahm, Francins Sahngun; Kim, Seog Gyun; Zehra, Tanzeel; Oh, So Won; Lee, Hyo Sang; Kang, Keon Wook; Chung, June Key; Lee, Myung Chul; Lee, Dong Soo

2011-01-01

Although the three phase bone scan (TBPS) is one of the widely used imaging studies for diagnosing complex regional pain syndrome type 1 (CRPS 1), there is some controversy regarding the TPBS image criteria for CRPS 1. In this study, we modified the image criteria using image pattern and quantitative analysis in the patients diagnosed using the most recent consensus clinical diagnostic criteria. The study included 140 patients with suspected CRPS 1 (CRPS 1, n=79; non CRPS, n=61; mean age 39±15 years) who underwent TPBS. The clinical diagnostic criteria for CRPS 1 revised by the Budapest consensus group were used for confirmative diagnosis. Patients were classified according to flow/pool and delayed uptake (DU) image patterns, and the time interval between the initiating event and TPBS (TI eventscan) . Quantitative analysis for lesion to contralateral ratio (LCR) was performed. Modified TPBS image criteria were created and evaluated for optimal diagnostic performance. Both increased and decreased periarticular DU were significant image findings for CRPS 1 (CRPS 1 positive rate=73% in the increased DU group, 75% in the decreased DU group). The TI eventscand id not differ significantly between the different image pattern groups. Quantitative analysis revealed an LCR of 1.43 was the optimal cutoff value for CRPS 1 and diagnostic performance was significantly improved in the increased DU group (area under the curve=0.732). Given the modified image criteria, the sensitivity and specificity of TPBS for diagnosing CRPS 1 were 80% and 72%, respectively. Optimally modified TPBS image criteria for CRPS 1 were suggested using image pattern and quantitative analysis. With the criteria, TPBS is an effective imaging study for CRPS 1 even with the most recent consensus clinical diagnostic criteria.

A GPS inspired Terrain Referenced Navigation algorithm

NARCIS (Netherlands)

Vaman, D.

2014-01-01

Terrain Referenced Navigation (TRN) refers to a form of localization in which measurements of distances to the terrain surface are matched with a digital elevation map allowing a vehicle to estimate its own position within the map. The main goal of this dissertation is to improve TRN performance

Diagnostic imaging of the equine tarsal region using radiography and ultrasonography. Part 1: the soft tissues.

Science.gov (United States)

Vanderperren, Katrien; Raes, Els; Hoegaerts, Michel; Saunders, Jimmy H

2009-02-01

The equine tarsus is the most commonly affected hindlimb region associated with lameness. Diagnostic imaging is routinely applied but because of its complexity, being composed of 10 multifaceted bones and different joints, multiple ligaments, tendons and bursae, imaging this region can be a challenge. This is the first part of a two-part review of the structures and disorders of the equine tarsus. It describes the principal disorders affecting the soft tissues of the tarsal region and addresses some of the technical aspects in taking radiographic, ultrasonographic and scintigraphic images of the different soft tissue lesions. Where applicable, comments on the diagnostic use of contrast radiography, arthroscopy and tenoscopy are made. In current clinical practice a combination of radiography and ultrasonography is still most frequently used to arrive at a diagnosis.

Characteristics of Criterion-Referenced Instruments: Implications for Materials Selection for the Learning Disabled.

Science.gov (United States)

Blasi, Joyce F.

Discussed are characteristics of criterion referenced reading tests for use with learning disabled (LD) children, and analyzed are the Basic Educational Skills Inventory (BESI), the Prescriptive Reading Inventory (PRI), and the Cooper-McGuire Diagnostic Work-Analysis Test (CooperMcGuire). Criterion referenced tests are defined; and problems in…

Three-dimentional imaging of dentomaxillofacial region using electron beam tomography

International Nuclear Information System (INIS)

Tanaka, Takemasa; Kanda, Shigenobu; Muranaka, Toru

1998-01-01

Authors reported their results of the 3-D imaging of dentomaxillofacial region mainly for jaw deformity with electron beam tomography (EBT). The EBT apparatus used was Imatron C-100 (Imatron Corp.), with which, using bremsstrahlung radiation generated from the electron beam, CT is possible with rapid scanning rate at <0.1 sec. Imaging was done with those conditions as tube voltage: 130 kV, current: 610 mA, scanning rate: 0.1 sec/slice whose thickness was 1.5 mm, feeding rate: 1.5 mm and number of slices: 40-170. Patients were 15 cases with jaw deformity. Data were processed for 3-D image by Scribe Imaging Workstation (Multi-dimensional Imaging Inc.) which giving surface rendering and further by Power Macintosh 8500 (Apple Computer Inc.) with VoxBlast 1.1.0 (VayTec Inc.) software which giving volume rendering or with Image 1.60 (NIH) which allowing multi-planar reconstruction and re-analog projection. These actual images were presented in the report. (K.H.)

Unemployment estimation: Spatial point referenced methods and models

KAUST Repository

Pereira, Soraia; Turkman, Kamil Feridun; Correia, Luis; Rue, Haavard

2017-01-01

Portuguese Labor force survey, from 4th quarter of 2014 onwards, started geo-referencing the sampling units, namely the dwellings in which the surveys are carried. This opens new possibilities in analysing and estimating unemployment and its spatial

Classification of hematopoietic regions in out-of-phase T{sub 1}-weighted images. A quantitative comparison study with T{sub 1}-weighted and STIR images

Energy Technology Data Exchange (ETDEWEB)

Amano, Yasuo; Amano, Maki; Kijima, Tetsuji; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

1995-07-01

The hematopoietic regions were classified into two groups on the basis of out-of-phase T{sub 1}-weighted images (op-TlWI): regions with lower intensity than that of muscle (LH) and regions with intensity equal to or higher than that of muscle (HH). We quantitatively evaluated the differences in signal intensity between LH and HH in order to examine this classification. Forty-two hematopoietic areas in aplastic anemia were classified into two groups of 23 LH and 19 HH. The signal ratios of hematopoietic areas to muscle on TlWI and STIR were calculated, and the differences between LH and HH were statistically evaluated. The signal ratios of LH were significantly higher on TlWI and lower on STIR than those of HH (unpaired t-test, p<0.05). This result indicated that LH consisted of more hypocellular marrow than HH. Op-TlWI were useful in differentiating between LH and HH and defining the degree of hematopoiesis in aplastic anemia. (author).

A framework of region-based dynamic image fusion

Institute of Scientific and Technical Information of China (English)

WANG Zhong-hua; QIN Zheng; LIU Yu

2007-01-01

A new framework of region-based dynamic image fusion is proposed. First, the technique of target detection is applied to dynamic images (image sequences) to segment images into different targets and background regions. Then different fusion rules are employed in different regions so that the target information is preserved as much as possible. In addition, steerable non-separable wavelet frame transform is used in the process of multi-resolution analysis, so the system achieves favorable characters of orientation and invariant shift. Compared with other image fusion methods, experimental results showed that the proposed method has better capabilities of target recognition and preserves clear background information.

Electronics. Criterion-Referenced Test (CRT) Item Bank.

Science.gov (United States)

Davis, Diane, Ed.

This document contains 519 criterion-referenced multiple choice and true or false test items for a course in electronics. The test item bank is designed to work with both the Vocational Instructional Management System (VIMS) and the Vocational Administrative Management System (VAMS) in Missouri. The items are grouped into 15 units covering the…

TH-A-18C-10: Dynamic Intensity Weighted Region of Interest Imaging

International Nuclear Information System (INIS)

Pearson, E; Pan, X; Pelizzari, C

2014-01-01

Purpose: For image guidance tasks full image quality is not required throughout the entire image. With dynamic filtration of the kV imaging beam the noise properties of the CT image can be locally controlled, providing a high quality image around the target volume with a lower quality surrounding region while providing substantial dose sparing to the patient as well as reduced scatter fluence on the detector. Methods: A dynamic collimation device with 3mm copper blades has been designed to mount in place of the bowtie filter on the On-Board Imager (Varian Medical Systems). The beam intensity is reduced by 95% behind the copper filters and the aperture is controlled dynamically to conformally illuminate a given ROI during a standard cone-beam CT scan. A data correction framework to account for the physical effects of the collimator prior to reconstruction was developed. Furthermore, to determine the dose savings and scatter reduction a monte carlo model was built in BEAMnrc with specifics from the Varian Monte Carlo Data Package. The MC model was validated with Gafchromic film. Results: The reconstructed image shows image quality comparable to a standard scan in the specified ROI, with higher noise and streaks in the outer region but still sufficient information for alignment to high contrast structures. The monte carlo modeling showed that the scatter-to-primary ratio was reduced from 1.26 for an unfiltered scan to 0.45 for an intensity weighted scan, suggesting that image quality may be improved in the inner ROI. Dose in the inner region was reduced 10–15% due to reduced scatter and by as much as 75% in the outer region. Conclusion: Dynamic intensity-weighted ROI imaging allows reduction of imaging dose to sensitive organs away from the target region while providing images that retain their utility for patient setup and procedure guidance. Funding was provided in part by Varian Medical Systems and NIH Grants 1RO1CA120540, T32EB002103, S10 RR021039 and P30 CA

Self-referenced memory, social cognition, and symptom presentation in autism.

Science.gov (United States)

Henderson, Heather A; Zahka, Nicole E; Kojkowski, Nicole M; Inge, Anne P; Schwartz, Caley B; Hileman, Camilla M; Coman, Drew C; Mundy, Peter C

2009-07-01

We examined performance on a self-referenced memory (SRM) task for higher-functioning children with autism (HFA) and a matched comparison group. SRM performance was examined in relation to symptom severity and social cognitive tests of mentalizing. Sixty-two children (31 HFA, 31 comparison; 8-16 years) completed a SRM task in which they read a list of words and decided whether the word described something about them, something about Harry Potter, or contained a certain number of letters. They then identified words that were familiar from a longer list. Dependent measures were memory performance (d') in each of the three encoding conditions as well as a self-memory bias score (d' self-d' other). Children completed The Strange Stories Task and The Children's Eyes Test as measures of social cognition. Parents completed the SCQ and ASSQ as measures of symptom severity. Children in the comparison sample showed the standard SRM effect in which they recognized significantly more self-referenced words relative to words in the other-referenced and letter conditions. In contrast, HFA children showed comparable rates of recognition for self- and other-referenced words. For all children, SRM performance improved with age and enhanced SRM performance was related to lower levels of social problems. These associations were not accounted for by performance on the mentalizing tasks. Children with HFA did not show the standard enhanced processing of self- vs. other-relevant information. Individual differences in the tendency to preferentially process self-relevant information may be associated with social cognitive processes that serve to modify the expression of social symptoms in children with autism.

Decision models for use with criterion-referenced tests

NARCIS (Netherlands)

van der Linden, Willem J.

1980-01-01

The problem of mastery decisions and optimizing cutoff scores on criterion-referenced tests is considered. This problem can be formalized as an (empirical) Bayes problem with decisions rules of a monotone shape. Next, the derivation of optimal cutoff scores for threshold, linear, and normal ogive

Estimation for sparse vegetation information in desertification region based on Tiangong-1 hyperspectral image.

Science.gov (United States)

Wu, Jun-Jun; Gao, Zhi-Hai; Li, Zeng-Yuan; Wang, Hong-Yan; Pang, Yong; Sun, Bin; Li, Chang-Long; Li, Xu-Zhi; Zhang, Jiu-Xing

2014-03-01

In order to estimate the sparse vegetation information accurately in desertification region, taking southeast of Sunite Right Banner, Inner Mongolia, as the test site and Tiangong-1 hyperspectral image as the main data, sparse vegetation coverage and biomass were retrieved based on normalized difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI), combined with the field investigation data. Then the advantages and disadvantages between them were compared. Firstly, the correlation between vegetation indexes and vegetation coverage under different bands combination was analyzed, as well as the biomass. Secondly, the best bands combination was determined when the maximum correlation coefficient turned up between vegetation indexes (VI) and vegetation parameters. It showed that the maximum correlation coefficient between vegetation parameters and NDVI could reach as high as 0.7, while that of SAVI could nearly reach 0.8. The center wavelength of red band in the best bands combination for NDVI was 630nm, and that of the near infrared (NIR) band was 910 nm. Whereas, when the center wavelength was 620 and 920 nm respectively, they were the best combination for SAVI. Finally, the linear regression models were established to retrieve vegetation coverage and biomass based on Tiangong-1 VIs. R2 of all models was more than 0.5, while that of the model based on SAVI was higher than that based on NDVI, especially, the R2 of vegetation coverage retrieve model based on SAVI was as high as 0.59. By intersection validation, the standard errors RMSE based on SAVI models were lower than that of the model based on NDVI. The results showed that the abundant spectral information of Tiangong-1 hyperspectral image can reflect the actual vegetaion condition effectively, and SAVI can estimate the sparse vegetation information more accurately than NDVI in desertification region.

Human body region enhancement method based on Kinect infrared imaging

Science.gov (United States)

Yang, Lei; Fan, Yubo; Song, Xiaowei; Cai, Wenjing

2016-10-01

To effectively improve the low contrast of human body region in the infrared images, a combing method of several enhancement methods is utilized to enhance the human body region. Firstly, for the infrared images acquired by Kinect, in order to improve the overall contrast of the infrared images, an Optimal Contrast-Tone Mapping (OCTM) method with multi-iterations is applied to balance the contrast of low-luminosity infrared images. Secondly, to enhance the human body region better, a Level Set algorithm is employed to improve the contour edges of human body region. Finally, to further improve the human body region in infrared images, Laplacian Pyramid decomposition is adopted to enhance the contour-improved human body region. Meanwhile, the background area without human body region is processed by bilateral filtering to improve the overall effect. With theoretical analysis and experimental verification, the results show that the proposed method could effectively enhance the human body region of such infrared images.

PLUME-FEATHER, Referencing and Finding Software for Research and Education

Science.gov (United States)

Bénassy, O.; Caron, C.; Ferret-Canape, C.; Cheylus, A.; Courcelle, E.; Dantec, C.; Dayre, P.; Dostes, T.; Durand, A.; Facq, A.; Gambini, G.; Geahchan, E.; Helft, C.; Hoffmann, D.; Ingarao, M.; Joly, P.; Kieffer, J.; Larré, J.-M.; Libes, M.; Morris, F.; Parmentier, H.; Pérochon, L.; Porte, O.; Romier, G.; Rousse, D.; Tournoy, R.; Valeins, H.

2014-06-01

PLUME-FEATHER is a non-profit project created to Promote economicaL, Useful and Maintained softwarEFor theHigher Education And THE Research communities. The site references software, mainly Free/Libre Open Source Software (FLOSS) from French universities and national research organisations, (CNRS, INRA...), laboratories or departments as well as other FLOSS software used and evaluated by users within these institutions. Each software is represented by a reference card, which describes origin, aim, installation, cost (if applicable) and user experience from the point of view of an academic user for academic users. Presently over 1000 programs are referenced on PLUME by more than 900 contributors. Although the server is maintained by a French institution, it is open to international contributions in the academic domain. All contained and validated contents are visible to anonymous public, whereas (presently more than 2000) registered users can contribute, starting with comments on single software reference cards up to help with the organisation and presentation of the referenced software products. The project has been presented to the HEP community in 2012 for the first time [1]. This is an update of the status and a call for (further) contributions.

PLUME-FEATHER, referencing and finding software for research and education

International Nuclear Information System (INIS)

Bénassy, O; Caron, C; Ferret-Canape, C; Cheylus, A; Courcelle, E; Dantec, C; Dayre, P; Dostes, T; Durand, A; Facq, A; Gambini, G; Morris, F; Geahchan, E; Helft, C; Hoffmann, D; Ingarao, M; Joly, P; Kieffer, J; Larré, J-M; Libes, M

2014-01-01

PLUME-FEATHER is a non-profit project created to Promote economicaL, Useful and Maintained softwarEFor theHigher Education And THE Research communities. The site references software, mainly Free/Libre Open Source Software (FLOSS) from French universities and national research organisations, (CNRS, INRA...), laboratories or departments as well as other FLOSS software used and evaluated by users within these institutions. Each software is represented by a reference card, which describes origin, aim, installation, cost (if applicable) and user experience from the point of view of an academic user for academic users. Presently over 1000 programs are referenced on PLUME by more than 900 contributors. Although the server is maintained by a French institution, it is open to international contributions in the academic domain. All contained and validated contents are visible to anonymous public, whereas (presently more than 2000) registered users can contribute, starting with comments on single software reference cards up to help with the organisation and presentation of the referenced software products. The project has been presented to the HEP community in 2012 for the first time [1]. This is an update of the status and a call for (further) contributions.

Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

Science.gov (United States)

Lions, Cynthia; Bucci, Maria Pia; Bonnet, Cédrick

2016-01-01

To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task), and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner.) We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions. Twelve healthy, young adults (17.3 to 34.1 years old) participated in this study. Postural performances were evaluated using the Multitest platform (Framiral®) and ocular recording was performed with Mobile T2 (e(ye)BRAIN®). In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene. Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions. As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1) the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2) the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

Directory of Open Access Journals (Sweden)

Cynthia Lions

Full Text Available To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task, and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner. We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions.Twelve healthy, young adults (17.3 to 34.1 years old participated in this study. Postural performances were evaluated using the Multitest platform (Framiral® and ocular recording was performed with Mobile T2 (e(yeBRAIN®. In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene.Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions.As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1 the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2 the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

Time series analysis of brain regional volume by MR image

International Nuclear Information System (INIS)

Tanaka, Mika; Tarusawa, Ayaka; Nihei, Mitsuyo; Fukami, Tadanori; Yuasa, Tetsuya; Wu, Jin; Ishiwata, Kiichi; Ishii, Kenji

2010-01-01

The present study proposed a methodology of time series analysis of volumes of frontal, parietal, temporal and occipital lobes and cerebellum because such volumetric reports along the process of individual's aging have been scarcely presented. Subjects analyzed were brain images of 2 healthy males and 18 females of av. age of 69.0 y, of which T1-weighted 3D SPGR (spoiled gradient recalled in the steady state) acquisitions with a GE SIGNA EXCITE HD 1.5T machine were conducted for 4 times in the time series of 42-50 months. The image size was 256 x 256 x (86-124) voxels with digitization level 16 bits. As the template for the regions, the standard gray matter atlas (icbn452 a tlas p robability g ray) and its labeled one (icbn.Labels), provided by UCLA Laboratory of Neuro Imaging, were used for individual's standardization. Segmentation, normalization and coregistration were performed with the MR imaging software SPM8 (Statistic Parametric Mapping 8). Volumes of regions were calculated as their voxel ratio to the whole brain voxel in percent. It was found that the regional volumes decreased with aging in all above lobes examined and cerebellum in average percent per year of -0.11, -0.07, -0.04, -0.02, and -0.03, respectively. The procedure for calculation of the regional volumes, which has been manually operated hitherto, can be automatically conducted for the individual brain using the standard atlases above. (T.T.)

Automatic Matching of Multi-Source Satellite Images: A Case Study on ZY-1-02C and ETM+

Directory of Open Access Journals (Sweden)

Bo Wang

2017-10-01

Full Text Available The ever-growing number of applications for satellites is being compromised by their poor direct positioning precision. Existing orthoimages, such as enhanced thematic mapper (ETM+ orthoimages, can provide georeferences or improve the geo-referencing accuracy of satellite images, such ZY-1-02C images that have unsatisfactory positioning precision, thus enhancing their processing efficiency and application. In this paper, a feasible image matching approach using multi-source satellite images is proposed on the basis of an experiment carried out with ZY-1-02C Level 1 images and ETM+ orthoimages. The proposed approach overcame differences in rotation angle, scale, and translation between images. The rotation and scale variances were evaluated on the basis of rational polynomial coefficients. The translation vectors were generated after blocking the overall phase correlation. Then, normalized cross-correlation and least-squares matching were applied for matching. Finally, the gross errors of the corresponding points were eliminated by local statistic vectors in a TIN structure. Experimental results showed a matching precision of less than two pixels (root-mean-square error, and comparison results indicated that the proposed method outperforms Scale-Invariant Feature Transform (SIFT, Speeded Up Robust Features (SURF, and Affine-Scale Invariant Feature Transform (A-SIFT in terms of reliability and efficiency.

Region-based multifocus image fusion for the precise acquisition of Pap smear images.

Science.gov (United States)

Tello-Mijares, Santiago; Bescós, Jesús

2018-05-01

A multifocus image fusion method to obtain a single focused image from a sequence of microscopic high-magnification Papanicolau source (Pap smear) images is presented. These images, captured each in a different position of the microscope lens, frequently show partially focused cells or parts of cells, which makes them unpractical for the direct application of image analysis techniques. The proposed method obtains a focused image with a high preservation of original pixels information while achieving a negligible visibility of the fusion artifacts. The method starts by identifying the best-focused image of the sequence; then, it performs a mean-shift segmentation over this image; the focus level of the segmented regions is evaluated in all the images of the sequence, and best-focused regions are merged in a single combined image; finally, this image is processed with an adaptive artifact removal process. The combination of a region-oriented approach, instead of block-based approaches, and a minimum modification of the value of focused pixels in the original images achieve a highly contrasted image with no visible artifacts, which makes this method especially convenient for the medical imaging domain. The proposed method is compared with several state-of-the-art alternatives over a representative dataset. The experimental results show that our proposal obtains the best and more stable quality indicators. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Ultrafast chirped optical waveform recorder using referenced heterodyning and a time microscope

Science.gov (United States)

Bennett, Corey Vincent [Livermore, CA

2011-11-22

A new technique for capturing both the amplitude and phase of an optical waveform is presented. This technique can capture signals with many THz of bandwidths in a single shot (e.g., temporal resolution of about 44 fs), or be operated repetitively at a high rate. That is, each temporal window (or frame) is captured single shot, in real time, but the process may be run repeatedly or single-shot. This invention expands upon previous work in temporal imaging by adding heterodyning, which can be self-referenced for improved precision and stability, to convert frequency chirp (the second derivative of phase with respect to time) into a time varying intensity modulation. By also including a variety of possible demultiplexing techniques, this process is scalable to recoding continuous signals.

Ultrafast chirped optical waveform recording using referenced heterodyning and a time microscope

Science.gov (United States)

Bennett, Corey Vincent

2010-06-15

A new technique for capturing both the amplitude and phase of an optical waveform is presented. This technique can capture signals with many THz of bandwidths in a single shot (e.g., temporal resolution of about 44 fs), or be operated repetitively at a high rate. That is, each temporal window (or frame) is captured single shot, in real time, but the process may be run repeatedly or single-shot. This invention expands upon previous work in temporal imaging by adding heterodyning, which can be self-referenced for improved precision and stability, to convert frequency chirp (the second derivative of phase with respect to time) into a time varying intensity modulation. By also including a variety of possible demultiplexing techniques, this process is scalable to recoding continuous signals.

Cusp/cleft region as observed by the Viking UV imager

International Nuclear Information System (INIS)

Garbe, G.P.; Murphree, J.S.; Cogger, L.L.; Woch, J.

1993-01-01

The authors report data taken by the Viking satellite at mid-altitudes (11,000-13,000 km) during northern hemispheric crossings of the cusp/cleft region. Particle signatures were used to divide the region into different categories. Data was looked at from the ultraviolet imager and particle diagnostics, when available. The authors discuss in detail two cases of crossing the cusp/cleft region, in order to look at the dynamics of a specific event, as opposed to other data analyses which have used large data sets to acquire good statistics, but which can thereby obscure dynamics of the actual events. Particle data were taken by the electron spectrometer ESP 1 and the ion spectrometer PISP 1/2. They looked at the spectral range 0.01 to 40 keV. The UV imager recorded 1 sec exposures of the auroral distribution once per minute. The data shows instantaneous observations of emissions, and does so for a narrow path swept by the satellite. Data indicate that the entire region is not a homogeneous region, but rather a very dynamic object. Conclusions include that the emissions observed are located at the footprint of the cleft region. The cusp region is located poleward of the region with continuous emission. The emission is observed to remain at a constant magnetic latitude during the period with IMF data, though B z swung 8nT during a 30 minute period

Pre-harvest assessment of perennial weeds in cereals based on images from unmanned aerial systems (UAS)

DEFF Research Database (Denmark)

Egilsson, Jon; Pedersen, Kim Steenstrup; Olsen, Søren Ingvor

2015-01-01

Unmanned aerial systems (UAS) are able to deliver images of agricultural fields of high spatial and temporal resolution. It is, however, not trivial to extract quantitative information about weed infestations from images. This study contributes to weed research by using state-of-the-art computer....... In order to provide ground truth prior to the modeling phase in Python, a subset of 600 images was annotated by experts with 16000 regions of weeds or crop. Following this, images were segmented into regions with weeds or crop by subdividing each image into 64 by 64 pixel patches and classifying each patch...... as either crop or weed. A collection of geo-referenced segmented images may subsequently be used to map weed occurrences in fields. To find a robust and fully automated assessment method both texture and color information was used to build a number of different competing weed-crop classifiers, including...

75 FR 50950 - Federal Speculative Position Limits for Referenced Energy Contracts and Associated Regulations

Science.gov (United States)

2010-08-18

..., section 4a(a) of the Act authorized the Commission to establish position limits for contracts traded on or... Position Limits for Referenced Energy Contracts and Associated Regulations AGENCY: Commodity Futures... and option contracts based on a limited set of exempt commodities,\\1\\ namely certain energy...

Efficient image duplicated region detection model using sequential block clustering

Czech Academy of Sciences Publication Activity Database

Sekeh, M. A.; Maarof, M. A.; Rohani, M. F.; Mahdian, Babak

2013-01-01

Roč. 10, č. 1 (2013), s. 73-84 ISSN 1742-2876 Institutional support: RVO:67985556 Keywords : Image forensic * Copy–paste forgery * Local block matching Subject RIV: IN - Informatics, Computer Science Impact factor: 0.986, year: 2013 http://library.utia.cas.cz/separaty/2013/ZOI/mahdian-efficient image duplicated region detection model using sequential block clustering.pdf

Energy Referencing in LANL HE-EOS Codes

Energy Technology Data Exchange (ETDEWEB)

Leiding, Jeffery Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Coe, Joshua Damon [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-10-19

Here, We briefly describe the choice of energy referencing in LANL's HE-EOS codes, HEOS and MAGPIE. Understanding this is essential to comparing energies produced by different EOS codes, as well as to the correct calculation of shock Hugoniots of HEs and other materials. In all equations after (3) throughout this report, all energies, enthalpies and volumes are assumed to be molar quantities.

Narrator Point of View and Persuasion in Health Narratives: The Role of Protagonist-Reader Similarity, Identification, and Self-Referencing.

Science.gov (United States)

Chen, Meng; Bell, Robert A; Taylor, Laramie D

2016-08-01

Narratives are often used in messages about health threats. We posited that a 1st-person point of view (POV) narrative would have a greater effect than a 3rd-person POV on the mediators identification and self-referencing-an effect moderated by protagonist-reader similarity. Higher levels of identification and self-referencing were expected to elevate susceptibility and severity perceptions, leading to persuasion. Participants ages ≤30 years were recruited from a crowdsource website and randomly assigned to read one version of a faux magazine article about caffeine overdose. Article versions were defined by a 2 (1st- or 3rd-person POV) × 2 (similar or dissimilar protagonist) design. To manipulate similarity, we had respondents read an article in which the protagonist was also young (24 years of age) and of the same sex or much older (54 years of age) and of the opposite sex. Participants then completed a questionnaire measuring study variables. Contrary to expectations, POV did not affect identification or self-referencing. However, similarity directly impacted identification, which in turn influenced severity perceptions. Self-referencing was not affected by the experimental manipulations but had a direct effect on susceptibility and also mediated the identification → susceptibility relationship. Susceptibility and severity perceptions were associated with greater levels of persuasion. Implications for message design are discussed.

Impact and characteristics of positive and fearful emotional messages during infant social referencing.

Science.gov (United States)

Kim, Geunyoung; Walden, Tedra A; Knieps, Linda J

2010-04-01

Studies of infant social referencing have indicated that infants might be more influenced by vocal information contained in emotional messages than by facial expression, especially during fearful message conditions. The present study investigated the characteristics of emotional channels that parents used during social referencing, and corresponding infants' behavioral changes. Results of Study 1 indicated that parents used more vocal information during positive message conditions. Unlike previous findings, infants' behavioral change was related to the frequency of vocal information during positive condition. For fearful messages, infants were more influenced by the number of multi-modal channels used and the frequency of visual information. Study 2 further showed that the intensity of vocal tone was related to infant regulation only during positive message conditions. The results imply that understanding of social context is important to make sense of parent-infant's emotional interaction. Copyright 2010 Elsevier Inc. All rights reserved.

MR imaging exploration of the pituitary region

International Nuclear Information System (INIS)

Braun, M.; Roland, J.; Moret, C.; Picard, L.

1992-01-01

MR Imaging has become the procedure of choice for the exploration of the pituitary region. MR contrast resolution is far better than the finest CT examination, especially concerning the microadenomas and the neurohypophysis. The present paper concerns, at first the major principles of magnetic resonance imaging, its application for the study of the pituitary region including the use of contrast agent (Gadolinium). Lastly, MR anatomy and physiological variations are presented

Functional photoacoustic imaging to observe regional brain activation induced by cocaine hydrochloride

Science.gov (United States)

Jo, Janggun; Yang, Xinmai

2011-09-01

Photoacoustic microscopy (PAM) was used to detect small animal brain activation in response to drug abuse. Cocaine hydrochloride in saline solution was injected into the blood stream of Sprague Dawley rats through tail veins. The rat brain functional change in response to the injection of drug was then monitored by the PAM technique. Images in the coronal view of the rat brain at the locations of 1.2 and 3.4 mm posterior to bregma were obtained. The resulted photoacoustic (PA) images showed the regional changes in the blood volume. Additionally, the regional changes in blood oxygenation were also presented. The results demonstrated that PA imaging is capable of monitoring regional hemodynamic changes induced by drug abuse.

Prediction errors to emotional expressions: the roles of the amygdala in social referencing.

Science.gov (United States)

Meffert, Harma; Brislin, Sarah J; White, Stuart F; Blair, James R

2015-04-01

Social referencing paradigms in humans and observational learning paradigms in animals suggest that emotional expressions are important for communicating valence. It has been proposed that these expressions initiate stimulus-reinforcement learning. Relatively little is known about the role of emotional expressions in reinforcement learning, particularly in the context of social referencing. In this study, we examined object valence learning in the context of a social referencing paradigm. Participants viewed objects and faces that turned toward the objects and displayed a fearful, happy or neutral reaction to them, while judging the gender of these faces. Notably, amygdala activation was larger when the expressions following an object were less expected. Moreover, when asked, participants were both more likely to want to approach, and showed stronger amygdala responses to, objects associated with happy relative to objects associated with fearful expressions. This suggests that the amygdala plays two roles in social referencing: (i) initiating learning regarding the valence of an object as a function of prediction errors to expressions displayed toward this object and (ii) orchestrating an emotional response to the object when value judgments are being made regarding this object. Published by Oxford University Press 2014. This work is written by US Government employees and is in the public domain in the US.

Development of an oxygen-sensitive degradable peptide probe for the imaging of hypoxia-inducible factor-1-active regions in tumors.

Science.gov (United States)

Ueda, Masashi; Ogawa, Kei; Miyano, Azusa; Ono, Masahiro; Kizaka-Kondoh, Shinae; Saji, Hideo

2013-12-01

We aimed to develop a radiolabeled peptide probe for the imaging of hypoxia-inducible factor-1 (HIF-1)-active tumors. We synthesized the peptide probes that contain or lack an essential sequence of the oxygen-dependent degradation of HIF-1α in proteasomes ((123/125)I-DKOP30 or (125)I-mDKOP, respectively). The degradation of probes was evaluated in vitro using cell lysates containing proteasomes. In vivo biodistribution study, planar imaging, autoradiography, and comparison between probe accumulation and HIF-1 transcriptional activity were also performed. The (125)I-DKOP30 underwent degradation in a proteasome-dependent manner, while (125)I-mDKOP was not degraded. Biodistribution analysis showed (125)I-DKOP30 accumulation in tumors. The tumors were clearly visualized by in vivo imaging, and intratumoral distribution of (125)I-DKOP30 coincided with the HIF-1α-positive hypoxic regions. Tumoral accumulation of (125)I-DKOP30 was significantly correlated with HIF-1-dependent luciferase bioluminescence, while that of (125)I-mDKOP was not. (123)I-DKOP30 is a useful peptide probe for the imaging of HIF-1-active tumors.

Astrometrically registered simultaneous observations of the 22 GHz H{sub 2}O and 43 GHz SiO masers toward R Leonis Minoris using KVN and source/frequency phase referencing

Energy Technology Data Exchange (ETDEWEB)

Dodson, Richard; Rioja, María J.; Jung, Tae-Hyun; Sohn, Bong-Won; Byun, Do-Young; Cho, Se-Hyung; Lee, Sang-Sung; Kim, Jongsoo; Kim, Kee-Tae; Oh, Chung-Sik; Han, Seog-Tae; Je, Do-Heung; Chung, Moon-Hee; Wi, Seog-Oh; Kang, Jiman; Lee, Jung-Won; Chung, Hyunsoo; Kim, Hyo-Ryoung; Kim, Hyun-Goo; Lee, Chang-Hoon, E-mail: rdodson@kasi.re.kr [Korea Astronomy and Space Science Institute, Daedeokdae-ro 776, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); and others

2014-11-01

Oxygen-rich asymptotic giant branch (AGB) stars can be intense emitters of SiO (v = 1 and 2, J = 1 → 0) and H{sub 2}O maser lines at 43 and 22 GHz, respectively. Very long baseline interferometry (VLBI) observations of the maser emission provide a unique tool to probe the innermost layers of the circumstellar envelopes in AGB stars. Nevertheless, the difficulties in achieving astrometrically aligned H{sub 2}O and v = 1 and v = 2 SiO maser maps have traditionally limited the physical constraints that can be placed on the SiO maser pumping mechanism. We present phase-referenced simultaneous spectral-line VLBI images for the SiO v = 1 and v = 2, J = 1 → 0, and H{sub 2}O maser emission around the AGB star R LMi, obtained from the Korean VLBI Network (KVN). The simultaneous multi-channel receivers of the KVN offer great possibilities for astrometry in the frequency domain. With this facility, we have produced images with bona fide absolute astrometric registration between high-frequency maser transitions of different species to provide the positions of the H{sub 2}O maser emission and the center of the SiO maser emission, hence reducing the uncertainty in the proper motions for R LMi by an order of magnitude over that from Hipparcos. This is the first successful demonstration of source frequency phase referencing for millimeter VLBI spectral-line observations and also where the ratio between the frequencies is not an integer.

A Brightness-Referenced Star Identification Algorithm for APS Star Trackers

Science.gov (United States)

Zhang, Peng; Zhao, Qile; Liu, Jingnan; Liu, Ning

2014-01-01

Star trackers are currently the most accurate spacecraft attitude sensors. As a result, they are widely used in remote sensing satellites. Since traditional charge-coupled device (CCD)-based star trackers have a limited sensitivity range and dynamic range, the matching process for a star tracker is typically not very sensitive to star brightness. For active pixel sensor (APS) star trackers, the intensity of an imaged star is valuable information that can be used in star identification process. In this paper an improved brightness referenced star identification algorithm is presented. This algorithm utilizes the k-vector search theory and adds imaged stars' intensities to narrow the search scope and therefore increase the efficiency of the matching process. Based on different imaging conditions (slew, bright bodies, etc.) the developed matching algorithm operates in one of two identification modes: a three-star mode, and a four-star mode. If the reference bright stars (the stars brighter than three magnitude) show up, the algorithm runs the three-star mode and efficiency is further improved. The proposed method was compared with other two distinctive methods the pyramid and geometric voting methods. All three methods were tested with simulation data and actual in orbit data from the APS star tracker of ZY-3. Using a catalog composed of 1500 stars, the results show that without false stars the efficiency of this new method is 4∼5 times that of the pyramid method and 35∼37 times that of the geometric method. PMID:25299950

Dogs' social referencing towards owners and strangers.

Science.gov (United States)

Merola, Isabella; Prato-Previde, Emanuela; Marshall-Pescini, Sarah

2012-01-01

Social referencing is a process whereby an individual uses the emotional information provided by an informant about a novel object/stimulus to guide his/her own future behaviour towards it. In this study adult dogs were tested in a social referencing paradigm involving a potentially scary object with either their owner or a stranger acting as the informant and delivering either a positive or negative emotional message. The aim was to evaluate the influence of the informant's identity on the dogs' referential looking behaviour and behavioural regulation when the message was delivered using only vocal and facial emotional expressions. Results show that most dogs looked referentially at the informant, regardless of his/her identity. Furthermore, when the owner acted as the informant dogs that received a positive emotional message changed their behaviour, looking at him/her more often and spending more time approaching the object and close to it; conversely, dogs that were given a negative message took longer to approach the object and to interact with it. Fewer differences in the dog's behaviour emerged when the informant was the stranger, suggesting that the dog-informant relationship may influence the dog's behavioural regulation. Results are discussed in relation to studies on human-dog communication, attachment, mood modification and joint attention.

Dogs' social referencing towards owners and strangers.

Directory of Open Access Journals (Sweden)

Isabella Merola

Full Text Available Social referencing is a process whereby an individual uses the emotional information provided by an informant about a novel object/stimulus to guide his/her own future behaviour towards it. In this study adult dogs were tested in a social referencing paradigm involving a potentially scary object with either their owner or a stranger acting as the informant and delivering either a positive or negative emotional message. The aim was to evaluate the influence of the informant's identity on the dogs' referential looking behaviour and behavioural regulation when the message was delivered using only vocal and facial emotional expressions. Results show that most dogs looked referentially at the informant, regardless of his/her identity. Furthermore, when the owner acted as the informant dogs that received a positive emotional message changed their behaviour, looking at him/her more often and spending more time approaching the object and close to it; conversely, dogs that were given a negative message took longer to approach the object and to interact with it. Fewer differences in the dog's behaviour emerged when the informant was the stranger, suggesting that the dog-informant relationship may influence the dog's behavioural regulation. Results are discussed in relation to studies on human-dog communication, attachment, mood modification and joint attention.

Empirical correlation between protein backbone {sup 15}N and {sup 13}C secondary chemical shifts and its application to nitrogen chemical shift re-referencing

Energy Technology Data Exchange (ETDEWEB)

Wang Liya [Cold Spring Harbor Laboratory (United States); Markley, John L. [University of Wisconsin, Biochemistry Department (United States)], E-mail: markley@nmrfam.wisc.edu

2009-06-15

The linear analysis of chemical shifts (LACS) has provided a robust method for identifying and correcting {sup 13}C chemical shift referencing problems in data from protein NMR spectroscopy. Unlike other approaches, LACS does not require prior knowledge of the three-dimensional structure or inference of the secondary structure of the protein. It also does not require extensive assignment of the NMR data. We report here a way of extending the LACS approach to {sup 15}N NMR data from proteins, so as to enable the detection and correction of inconsistencies in chemical shift referencing for this nucleus. The approach is based on our finding that the secondary {sup 15}N chemical shift of the backbone nitrogen atom of residue i is strongly correlated with the secondary chemical shift difference (experimental minus random coil) between the alpha and beta carbons of residue i - 1. Thus once alpha and beta {sup 13}C chemical shifts are available (their difference is referencing error-free), the {sup 15}N referencing can be validated, and an appropriate offset correction can be derived. This approach can be implemented prior to a structure determination and can be used to analyze potential referencing problems in database data not associated with three-dimensional structure. Application of the LACS algorithm to the current BMRB protein chemical shift database, revealed that nearly 35% of the BMRB entries have {delta}{sup 15}N values mis-referenced by over 0.7 ppm and over 25% of them have {delta}{sup 1}H{sup N} values mis-referenced by over 0.12 ppm. One implication of the findings reported here is that a backbone {sup 15}N chemical shift provides a better indicator of the conformation of the preceding residue than of the residue itself.

A Criterion-Referenced Approach to Student Ratings of Instruction

Science.gov (United States)

Meyer, J. Patrick; Doromal, Justin B.; Wei, Xiaoxin; Zhu, Shi

2017-01-01

We developed a criterion-referenced student rating of instruction (SRI) to facilitate formative assessment of teaching. It involves four dimensions of teaching quality that are grounded in current instructional design principles: Organization and structure, Assessment and feedback, Personal interactions, and Academic rigor. Using item response…

Polarization and infrared imaging of regions of star formation

International Nuclear Information System (INIS)

Moneti, A.

1985-01-01

Observational studies of two regions of star formation, the Taurus cloud and the BN-KL region of Orion, are presented. The magnetic field structure in the Taurus cloud was studied in order to investigate its possible role in the evolution of the cloud. It was found that the magnetic field is generally perpendicular to the elongated structures that make up the cloud, and it is deduced that the observed structure could be due to the effects of the magnetic field during the early stages of collapse. In addition, it was found that the magnetic field may have prevented the formation of massive stars by inhibiting the collapse of large cores, while not affecting the collapse of the small ones. Using a new near-infrared array camera, high resolution (1'') images of several young stars embedded in the cloud were obtained. Most of these sources have extended, spatially resolved circumstellar shells. High resolution images of the BN-KL region of Orion at four wavelengths between 1.65 and 4.7 μm were also obtained. At 1.65 μm a large trough is seen in the overall nebulosity; it is suggested that the observed trough is due to the doughnut of material around IRc2 as it obscures the background nebulosity

A guide to the Harvard referencing system.

Science.gov (United States)

Dwyer, M

This article explains how to reference an academic work using the Harvard system. Instructions comply with the relevant British standards, i.e. BS 5605:1990, BS 1629:1989 and BS 6371:1983. The importance of referencing in an approved manner is discussed and problem areas such as joint authors, corporate authorship and unpublished works are examined. The issue of second-hand references that are not addressed by the standards is also explained.

Modern referencing trends in philosophical research papers

OpenAIRE

Muñoz-Alonso López, Gemma

2006-01-01

El artículo propone unificar los criterios para citar y elaborar bibliografías en la investigación en filosofía y en ciencias humanas. Se analizan las ventajas y los inconvenientes del sistema tradicional y del sistema Harvard.The paper attempts to unify criteria for referencing documents and elaborating bibliographies in philosophy and human sciences research. The advantages and disadvantages of the Harvard system are confronted with more traditional methods.

Management of information for mission operations using automated keyword referencing

Science.gov (United States)

Davidson, Roger A.; Curran, Patrick S.

1993-01-01

Although millions of dollars have helped to improve the operability and technology of ground data systems for mission operations, almost all mission documentation remains bound in printed volumes. This form of documentation is difficult and timeconsuming to use, may be out-of-date, and is usually not cross-referenced with other related volumes of mission documentation. A more effective, automated method of mission information access is needed. A new method of information management for mission operations using automated keyword referencing is proposed. We expound on the justification for and the objectives of this concept. The results of a prototype tool for mission information access that uses a hypertextlike user interface and existing mission documentation are shared. Finally, the future directions and benefits of our proposed work are described.

Refining a region-of-interest within an available CT image

International Nuclear Information System (INIS)

Enjilela, Esmaeil; Hussein, Esam M.A.

2013-01-01

This paper describes a numerical method for refining the image of a region-of-interest (RoI) within an existing tomographic slice, provided that projection data are stored along with the image. Using the attributes of the image, projection values (ray-sums) are adjusted to compensate for the material outside the RoI. Advantage is taken of the high degree of overdetermination of common computed tomography systems to reconstruct an RoI image over smaller pixels. The smaller size of a region-of-interest enables the use of iterative methods for RoI image reconstruction, which are less prone to error propagation. Simulation results are shown for an anthropomorphic head phantom, demonstrating that the introduced approach enhances both the spatial resolution and material contrast of RoI images; without the need to acquire any additional measurements or to alter existing imaging setups and systems. - Highlights: ► A method for refining the image of a region-of-interest within an existing tomographic image. ► Refined spatial-resolution within the region-of-interest, due to high redundancy of CT data. ► Enhancement in image contrast by the use of iterative image reconstruction, made possible by the smaller problem size. ► No need for additional measurements, no alteration of existing imaging setups and systems

Dilemma of diagnosing thoracic sarcoidosis in tuberculosis endemic regions: An imaging-based approach. Part 1

Directory of Open Access Journals (Sweden)

Ashu S Bhalla

2017-01-01

Full Text Available Sarcoidosis is a multi-systemic disorder of unknown etiology, although commonly believed to be immune-mediated. Histologically, it is characterized by noncaseating granuloma which contrasts against the caseating granuloma seen in tuberculosis (TB, an infectious disease that closely mimics sarcoidosis, both clinically as well as radiologically. In TB-endemic regions, the overlapping clinico-radiological manifestations create significant diagnostic dilemma, especially since the management options are markedly different in the two entities. Part 1 of this review aims to summarize the clinical, laboratory, and imaging features of sarcoidosis, encompassing both typical and atypical manifestations, in an attempt to distinguish between the two disease entities.

MR imaging of pituitary region lesions with gadodiamide injection

International Nuclear Information System (INIS)

Hald, J.K.; Skalpe, I.O.; Bakke, S.J.; Nakstad, P.H.

1994-01-01

Twelve patients with known or suspected pituitary lesions underwent MR imaging with gadodiamide injection at a dose of 0.1 (n = 5) or 0.3 (n = 7) mM/kg. Six of the patients were also studied with 0.1 mM/kg gadopentetate dimeglumine. Consistent with previous reports gadodiamide injection was found to be a safe and effective contrast medium for MR imaging of the pituitary region. No additional diagnostic information was obtained using 0.3 mM/kg gadodiamide injection compared to 0.1 mM/kg gadopentetate dimeglumine in the same patients. The high dose (0.3 mM/kg) gadodiamide injection in 7 patients did not shorten the T2 value sufficiently to overwhelm the T1 shortening and leave pathologic lesions hypo-intense compared to precontrast studies. With the comparable relaxivities of gadodiamide injection and gadopentetate dimeglumine, similarities in results have to be expected when using these media for MR image enhancement. (orig.)

Repetitive Domain-Referenced Testing Using Computers: the TITA System.

Science.gov (United States)

Olympia, P. L., Jr.

The TITA (Totally Interactive Testing and Analysis) System algorithm for the repetitive construction of domain-referenced tests utilizes a compact data bank, is highly portable, is useful in any discipline, requires modest computer hardware, and does not present a security problem. Clusters of related keyphrases, statement phrases, and distractors…

The Concept of Performance Levels in Criterion-Referenced Assessment.

Science.gov (United States)

Hewitson, Mal

The concept of performance levels in criterion-referenced assessment is explored by applying the idea to different types of tests commonly used in schools, mastery tests (including diagnostic tests) and achievement tests. In mastery tests, a threshold performance standard must be established for each criterion. Attainment of this threshold…

Region-Based Color Image Indexing and Retrieval

DEFF Research Database (Denmark)

Kompatsiaris, Ioannis; Triantafyllou, Evangelia; Strintzis, Michael G.

2001-01-01

In this paper a region-based color image indexing and retrieval algorithm is presented. As a basis for the indexing, a novel K-Means segmentation algorithm is used, modified so as to take into account the coherence of the regions. A new color distance is also defined for this algorithm. Based on ....... Experimental results demonstrate the performance of the algorithm. The development of an intelligent image content-based search engine for the World Wide Web is also presented, as a direct application of the presented algorithm....

Performance Evaluation and Requirements Assessment for Gravity Gradient Referenced Navigation

Directory of Open Access Journals (Sweden)

Jisun Lee

2015-07-01

Full Text Available In this study, simulation tests for gravity gradient referenced navigation (GGRN are conducted to verify the effects of various factors such as database (DB and sensor errors, flight altitude, DB resolution, initial errors, and measurement update rates on the navigation performance. Based on the simulation results, requirements for GGRN are established for position determination with certain target accuracies. It is found that DB and sensor errors and flight altitude have strong effects on the navigation performance. In particular, a DB and sensor with accuracies of 0.1 E and 0.01 E, respectively, are required to determine the position more accurately than or at a level similar to the navigation performance of terrain referenced navigation (TRN. In most cases, the horizontal position error of GGRN is less than 100 m. However, the navigation performance of GGRN is similar to or worse than that of a pure inertial navigation system when the DB and sensor errors are 3 E or 5 E each and the flight altitude is 3000 m. Considering that the accuracy of currently available gradiometers is about 3 E or 5 E, GGRN does not show much advantage over TRN at present. However, GGRN is expected to exhibit much better performance in the near future when accurate DBs and gravity gradiometer are available.

Novel region of interest interrogation technique for diffusion tensor imaging analysis in the canine brain.

Science.gov (United States)

Li, Jonathan Y; Middleton, Dana M; Chen, Steven; White, Leonard; Ellinwood, N Matthew; Dickson, Patricia; Vite, Charles; Bradbury, Allison; Provenzale, James M

2017-08-01

Purpose We describe a novel technique for measuring diffusion tensor imaging metrics in the canine brain. We hypothesized that a standard method for region of interest placement could be developed that is highly reproducible, with less than 10% difference in measurements between raters. Methods Two sets of canine brains (three seven-week-old full-brains and two 17-week-old single hemispheres) were scanned ex-vivo on a 7T small-animal magnetic resonance imaging system. Strict region of interest placement criteria were developed and then used by two raters to independently measure diffusion tensor imaging metrics within four different white-matter regions within each specimen. Average values of fractional anisotropy, radial diffusivity, and the three eigenvalues (λ1, λ2, and λ3) within each region in each specimen overall and within each individual image slice were compared between raters by calculating the percentage difference between raters for each metric. Results The mean percentage difference between raters for all diffusion tensor imaging metrics when pooled by each region and specimen was 1.44% (range: 0.01-5.17%). The mean percentage difference between raters for all diffusion tensor imaging metrics when compared by individual image slice was 2.23% (range: 0.75-4.58%) per hemisphere. Conclusion Our results indicate that the technique described is highly reproducible, even when applied to canine specimens of differing age, morphology, and image resolution. We propose this technique for future studies of diffusion tensor imaging analysis in canine brains and for cross-sectional and longitudinal studies of canine brain models of human central nervous system disease.

UNDERCOVER EUV SOLAR JETS OBSERVED BY THE INTERFACE REGION IMAGING SPECTROGRAPH

Energy Technology Data Exchange (ETDEWEB)

Chen, N.-H. [Korea Astronomy and Space Science Institute, Daejeon (Korea, Republic of); Innes, D. E. [Max-Planck-Institut für Sonnensystemforschung, D-37077 Göttingen (Germany)

2016-12-10

It is well-known that extreme ultraviolet (EUV) emission emitted at the solar surface is absorbed by overlying cool plasma. Especially in active regions, dark lanes in EUV images suggest that much of the surface activity is obscured. Simultaneous observations from the Interface Region Imaging Spectrograph, consisting of UV spectra and slit-jaw images (SJI), give vital information with sub-arcsecond spatial resolution on the dynamics of jets not seen in EUV images. We studied a series of small jets from recently formed bipole pairs beside the trailing spot of active region 11991, which occurred on 2014 March 5 from 15:02:21 UT to 17:04:07 UT. Collimated outflows with bright roots were present in SJI 1400 Å (transition region) and 2796 Å (upper chromosphere) that were mostly not seen in Atmospheric Imaging Assembly (AIA) 304 Å (transition region) and AIA 171 Å (lower corona) images. The Si iv spectra show a strong blue wing enhancement, but no red wing, in the line profiles of the ejecta for all recurrent jets, indicating outward flows without twists. We see two types of Mg ii line profiles produced by the jets spires: reversed and non-reversed. Mg ii lines remain optically thick, but turn optically thin in the highly Doppler shifted wings. The energy flux contained in each recurrent jet is estimated using a velocity differential emission measure technique that measures the emitting power of the plasma as a function of the line-of-sight velocity. We found that all the recurrent jets release similar energy (10{sup 8} erg cm{sup −2} s{sup −1}) toward the corona and the downward component is less than 3%.

Finding regions of interest in pathological images: an attentional model approach

Science.gov (United States)

Gómez, Francisco; Villalón, Julio; Gutierrez, Ricardo; Romero, Eduardo

2009-02-01

This paper introduces an automated method for finding diagnostic regions-of-interest (RoIs) in histopathological images. This method is based on the cognitive process of visual selective attention that arises during a pathologist's image examination. Specifically, it emulates the first examination phase, which consists in a coarse search for tissue structures at a "low zoom" to separate the image into relevant regions.1 The pathologist's cognitive performance depends on inherent image visual cues - bottom-up information - and on acquired clinical medicine knowledge - top-down mechanisms -. Our pathologist's visual attention model integrates the latter two components. The selected bottom-up information includes local low level features such as intensity, color, orientation and texture information. Top-down information is related to the anatomical and pathological structures known by the expert. A coarse approximation to these structures is achieved by an oversegmentation algorithm, inspired by psychological grouping theories. The algorithm parameters are learned from an expert pathologist's segmentation. Top-down and bottom-up integration is achieved by calculating a unique index for each of the low level characteristics inside the region. Relevancy is estimated as a simple average of these indexes. Finally, a binary decision rule defines whether or not a region is interesting. The method was evaluated on a set of 49 images using a perceptually-weighted evaluation criterion, finding a quality gain of 3dB when comparing to a classical bottom-up model of attention.

X-ray CCD image sensor with a thick depletion region

International Nuclear Information System (INIS)

Saito, Hirobumi; Watabe, Hiroshi.

1984-01-01

To develop a solid-state image sensor for high energy X-ray above 1 -- 2 keV, basic studies have been made on the CCD (charge coupled device) with a thick depletion region. A method of super-imposing a high DC bias voltage on low voltage signal pulses was newly proposed. The characteristics of both SCCD and BCCD were investigated, and their ability as X-ray sensors was compared. It was found that a depletion region of 60 μm thick was able to be obtained with ordinary doping density of 10 20 /m 3 , and that even thicker over 1 mm depletion region was able to be obtained with doping density of about 10 18 /m 3 , and a high bias voltage above 1 kV was able to be applied. It is suggested that the CCD image sensors for 8 keV or 24 keV X-ray can be realized since the absorption length of these X-ray in Si is about 60 μm and 1 mm, respectively. As for the characteristics other than the depletion thickness, the BCCD is preferable to SCCD for the present purpose because of lower noise and dark current. As for the transfer method, the frame-transfer method is recommended. (Aoki, K.)

A filtering approach to edge preserving MAP estimation of images.

Science.gov (United States)

Humphrey, David; Taubman, David

2011-05-01

The authors present a computationally efficient technique for maximum a posteriori (MAP) estimation of images in the presence of both blur and noise. The image is divided into statistically independent regions. Each region is modelled with a WSS Gaussian prior. Classical Wiener filter theory is used to generate a set of convex sets in the solution space, with the solution to the MAP estimation problem lying at the intersection of these sets. The proposed algorithm uses an underlying segmentation of the image, and a means of determining the segmentation and refining it are described. The algorithm is suitable for a range of image restoration problems, as it provides a computationally efficient means to deal with the shortcomings of Wiener filtering without sacrificing the computational simplicity of the filtering approach. The algorithm is also of interest from a theoretical viewpoint as it provides a continuum of solutions between Wiener filtering and Inverse filtering depending upon the segmentation used. We do not attempt to show here that the proposed method is the best general approach to the image reconstruction problem. However, related work referenced herein shows excellent performance in the specific problem of demosaicing.

Determination of Exterior Orientation Parameters Through Direct Geo-Referencing in a Real-Time Aerial Monitoring System

Science.gov (United States)

Kim, H.; Lee, J.; Choi, K.; Lee, I.

2012-07-01

Rapid responses for emergency situations such as natural disasters or accidents often require geo-spatial information describing the on-going status of the affected area. Such geo-spatial information can be promptly acquired by a manned or unmanned aerial vehicle based multi-sensor system that can monitor the emergent situations in near real-time from the air using several kinds of sensors. Thus, we are in progress of developing such a real-time aerial monitoring system (RAMS) consisting of both aerial and ground segments. The aerial segment acquires the sensory data about the target areas by a low-altitude helicopter system equipped with sensors such as a digital camera and a GPS/IMU system and transmits them to the ground segment through a RF link in real-time. The ground segment, which is a deployable ground station installed on a truck, receives the sensory data and rapidly processes them to generate ortho-images, DEMs, etc. In order to generate geo-spatial information, in this system, exterior orientation parameters (EOP) of the acquired images are obtained through direct geo-referencing because it is difficult to acquire coordinates of ground points in disaster area. The main process, since the data acquisition stage until the measurement of EOP, is discussed as follows. First, at the time of data acquisition, image acquisition time synchronized by GPS time is recorded as part of image file name. Second, the acquired data are then transmitted to the ground segment in real-time. Third, by processing software for ground segment, positions/attitudes of acquired images are calculated through a linear interpolation using the GPS time of the received position/attitude data and images. Finally, the EOPs of images are obtained from position/attitude data by deriving the relationships between a camera coordinate system and a GPS/IMU coordinate system. In this study, we evaluated the accuracy of the EOP decided by direct geo-referencing in our system. To perform this

DETERMINATION OF EXTERIOR ORIENTATION PARAMETERS THROUGH DIRECT GEO-REFERENCING IN A REAL-TIME AERIAL MONITORING SYSTEM

Directory of Open Access Journals (Sweden)

H. Kim

2012-07-01

Full Text Available Rapid responses for emergency situations such as natural disasters or accidents often require geo-spatial information describing the on-going status of the affected area. Such geo-spatial information can be promptly acquired by a manned or unmanned aerial vehicle based multi-sensor system that can monitor the emergent situations in near real-time from the air using several kinds of sensors. Thus, we are in progress of developing such a real-time aerial monitoring system (RAMS consisting of both aerial and ground segments. The aerial segment acquires the sensory data about the target areas by a low-altitude helicopter system equipped with sensors such as a digital camera and a GPS/IMU system and transmits them to the ground segment through a RF link in real-time. The ground segment, which is a deployable ground station installed on a truck, receives the sensory data and rapidly processes them to generate ortho-images, DEMs, etc. In order to generate geo-spatial information, in this system, exterior orientation parameters (EOP of the acquired images are obtained through direct geo-referencing because it is difficult to acquire coordinates of ground points in disaster area. The main process, since the data acquisition stage until the measurement of EOP, is discussed as follows. First, at the time of data acquisition, image acquisition time synchronized by GPS time is recorded as part of image file name. Second, the acquired data are then transmitted to the ground segment in real-time. Third, by processing software for ground segment, positions/attitudes of acquired images are calculated through a linear interpolation using the GPS time of the received position/attitude data and images. Finally, the EOPs of images are obtained from position/attitude data by deriving the relationships between a camera coordinate system and a GPS/IMU coordinate system. In this study, we evaluated the accuracy of the EOP decided by direct geo-referencing in our system

Image patch analysis of sunspots and active regions

Directory of Open Access Journals (Sweden)

Moon Kevin R.

2016-01-01

Full Text Available Context. Separating active regions that are quiet from potentially eruptive ones is a key issue in Space Weather applications. Traditional classification schemes such as Mount Wilson and McIntosh have been effective in relating an active region large scale magnetic configuration to its ability to produce eruptive events. However, their qualitative nature prevents systematic studies of an active region’s evolution for example. Aims. We introduce a new clustering of active regions that is based on the local geometry observed in Line of Sight magnetogram and continuum images. Methods. We use a reduced-dimension representation of an active region that is obtained by factoring the corresponding data matrix comprised of local image patches. Two factorizations can be compared via the definition of appropriate metrics on the resulting factors. The distances obtained from these metrics are then used to cluster the active regions. Results. We find that these metrics result in natural clusterings of active regions. The clusterings are related to large scale descriptors of an active region such as its size, its local magnetic field distribution, and its complexity as measured by the Mount Wilson classification scheme. We also find that including data focused on the neutral line of an active region can result in an increased correspondence between our clustering results and other active region descriptors such as the Mount Wilson classifications and the R-value. Conclusions. Matrix factorization of image patches is a promising new way of characterizing active regions. We provide some recommendations for which metrics, matrix factorization techniques, and regions of interest to use to study active regions.

A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

Science.gov (United States)

Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

2012-01-01

A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C1 continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung. PMID:23794749

A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

Energy Technology Data Exchange (ETDEWEB)

Yin, Youbing, E-mail: youbing-yin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Choi, Jiwoong, E-mail: jiwoong-choi@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A., E-mail: eric-hoffman@uiowa.edu [Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242 (United States); Tawhai, Merryn H., E-mail: m.tawhai@auckland.ac.nz [Auckland Bioengineering Institute, The University of Auckland, Auckland (New Zealand); Lin, Ching-Long, E-mail: ching-long-lin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States)

2013-07-01

A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

Diagnostic imaging of the equine fetlock region using radiography and ultrasonography. Part 1: Soft tissues.

Science.gov (United States)

Vanderperren, Katrien; Saunders, Jimmy H

2009-08-01

The equine fetlock is the joint most commonly associated with lameness. Although the fetlock is regarded as a simple joint, diagnosis of a fetlock disorder can be a challenge and various imaging modalities are routinely used to arrive at an accurate diagnosis. This review describes the principal disorders affecting the soft tissues of the fetlock region and addresses some of the technical aspects involved in taking radiographic and ultrasonographic images of the different soft tissue lesions. A combination of radiography and ultrasonography is still the most commonly used diagnostic approach in clinical practice.

Relationships between narrative language samples and norm-referenced test scores in language assessments of school-age children.

Science.gov (United States)

Danahy Ebert, Kerry; Scott, Cheryl M

2014-10-01

Both narrative language samples and norm-referenced language tests can be important components of language assessment for school-age children. The present study explored the relationship between these 2 tools within a group of children referred for language assessment. The study is a retrospective analysis of clinical records from 73 school-age children. Participants had completed an oral narrative language sample and at least one norm-referenced language test. Correlations between microstructural language sample measures and norm-referenced test scores were compared for younger (6- to 8-year-old) and older (9- to 12-year-old) children. Contingency tables were constructed to compare the 2 types of tools, at 2 different cutpoints, in terms of which children were identified as having a language disorder. Correlations between narrative language sample measures and norm-referenced tests were stronger for the younger group than the older group. Within the younger group, the level of language assessed by each measure contributed to associations among measures. Contingency analyses revealed moderate overlap in the children identified by each tool, with agreement affected by the cutpoint used. Narrative language samples may complement norm-referenced tests well, but age combined with narrative task can be expected to influence the nature of the relationship.

Age Differences in Neural Response to Stereotype Threat and Resiliency for Self-Referenced Information

Directory of Open Access Journals (Sweden)

Gabriel eColton

2013-09-01

Full Text Available To investigate the contribution of cortical midline regions to stereotype threat and resiliency, we compared age groups in an event-related functional MRI study. During scanning, seventeen younger and sixteen older adults judged whether words stereotypical of aging and control words described them. Judging stereotype words versus control words revealed higher activations in posterior midline regions associated with self-referencing, including the precuneus, for older adults compared to younger adults. While heightening salience of stereotypes can evoke a threat response, detrimentally affecting performance, invoking stereotypes can also lead to a phenomenon called resilience, where older adults use those stereotypes to create downward social comparisons to other older adults and elevate their own self-perception. In an exploration of brain regions underlying stereotype threat responses as well as resilience responses, we found significant activation in older adults for threat over resilient responses in posterior midline regions including the precuneus, associated with self-reflective thought, and parahippocampal gyrus, implicated in autobiographical memory. These findings have implications for understanding how aging stereotypes may affect the engagement of regions associated with contextual and social processing of self-relevant information, indicating ways in which stereotype threat can affect the engagement of neural resources with age.

Integrated GNSS attitude determination and positioning for direct geo-referencing

NARCIS (Netherlands)

Nadarajah, N.; Paffenholz, J.A.; Teunissen, P.J.G.

2014-01-01

Direct geo-referencing is an efficient methodology for the fast acquisition of 3D spatial data. It requires the fusion of spatial data acquisition sensors with navigation sensors, such as Global Navigation Satellite System (GNSS) receivers. In this contribution, we consider an integrated GNSS

iMAGE cloud: medical image processing as a service for regional healthcare in a hybrid cloud environment.

Science.gov (United States)

Liu, Li; Chen, Weiping; Nie, Min; Zhang, Fengjuan; Wang, Yu; He, Ailing; Wang, Xiaonan; Yan, Gen

2016-11-01

To handle the emergence of the regional healthcare ecosystem, physicians and surgeons in various departments and healthcare institutions must process medical images securely, conveniently, and efficiently, and must integrate them with electronic medical records (EMRs). In this manuscript, we propose a software as a service (SaaS) cloud called the iMAGE cloud. A three-layer hybrid cloud was created to provide medical image processing services in the smart city of Wuxi, China, in April 2015. In the first step, medical images and EMR data were received and integrated via the hybrid regional healthcare network. Then, traditional and advanced image processing functions were proposed and computed in a unified manner in the high-performance cloud units. Finally, the image processing results were delivered to regional users using the virtual desktop infrastructure (VDI) technology. Security infrastructure was also taken into consideration. Integrated information query and many advanced medical image processing functions-such as coronary extraction, pulmonary reconstruction, vascular extraction, intelligent detection of pulmonary nodules, image fusion, and 3D printing-were available to local physicians and surgeons in various departments and healthcare institutions. Implementation results indicate that the iMAGE cloud can provide convenient, efficient, compatible, and secure medical image processing services in regional healthcare networks. The iMAGE cloud has been proven to be valuable in applications in the regional healthcare system, and it could have a promising future in the healthcare system worldwide.

Regional Cerebral Disease Progression in Friedreich's Ataxia: A Longitudinal Diffusion Tensor Imaging Study.

Science.gov (United States)

Mascalchi, Mario; Toschi, Nicola; Giannelli, Marco; Ginestroni, Andrea; Della Nave, Riccardo; Tessa, Carlo; Piacentini, Silvia; Dotti, Maria Teresa; Aiello, Marco; Nicolai, Emanuele; Soricelli, Andrea; Salvi, Fabrizio; Diciotti, Stefano

2016-01-01

Imaging biomarkers of disease progression are desirable in inherited ataxias. MRI has demonstrated brain damage in Friedreich ataxia (FRDA) in form of regional atrophy of the medulla, peridentate cerebellar white matter (WM) and superior cerebellar peduncles (visible in T1-weighted images) and of change of microstructural characteristics of WM tracts of the brainstem, cerebellar peduncles, cerebellum, and supratentorial structures (visible through diffusion-weighted imaging). We explored the potential of brain MR morphometry and diffusion tensor imaging (DTI) to track the progression of neurodegeneration in FRDA. Eight patients (5F, 3M; age 13.4-41.2 years) and 8 healthy controls (2F, 6M; age 26.2-48.3 years) underwent 2 MRI examinations (mean 3.9 and 4.1 years apart, respectively) on the same 1.5T scanner. The protocol included 3D T1-weighted images and axial diffusion-weighted images (b-value 1,000 s/mm(2)) for calculating maps of fractional anisotropy, mean, axial and radial diffusivity, and mode of anisotropy. Tensor-based morphometry was used to investigate regional volume changes and tract-based spatial statistics was used to investigate microstructural changes in WM tracts. Longitudinal analyses showed no differences in regional volume changes but a significant difference in axial diffusivity changes in cerebral and corpus callosum WM of patients as compared to controls (mean longitudinal rate of change for axial diffusivity: -.02 × 10(-3) mm(2)/s/year in patients vs. .01 × 10(-3) mm(2)/s/year in controls). No correlation with number of triplets, disease duration, and worsening of the clinical deficit was observed. DTI can track brain microstructural changes in FRDA and can be considered a potential biomarker of disease progression. Copyright © 2015 by the American Society of Neuroimaging.

Retrospective chart review of a referenced EEG database in assisting medication selection for treatment of depression in patients with eating disorders

Directory of Open Access Journals (Sweden)

Greenblatt JM

2011-09-01

Full Text Available James M Greenblatt1, Craig Sussman1, Mariko Jameson1, Lee Yuan1, Daniel A Hoffman2, Dan V Iosifescu31Comprehensive Psychiatric Resources, Waltham, MA, USA; 2Neuro-Therapy Clinic Inc, Denver, CO, USA; 3Mood and Anxiety Disorders Program, Mount Sinai School of Medicine, New York, NY, USABackground: A retrospective chart review was undertaken in a private clinic to examine the clinical outcomes for patients with an eating disorder comorbid with depression or bipolar illness who underwent a referenced electroencephalographic (EEG database analysis to help guide medication selection.Method: We examined 33 charts for patients with the primary psychiatric diagnosis of an eating disorder and comorbid major depressive disorder or bipolar disorder who underwent a quantitative EEG database assessment to provide additional information for choices of medication. The current analysis includes data from 22 subjects who accepted treatments based on information from the referenced-EEG medication database. Hamilton Depression Rating Scale, Clinical Global Impression-Severity, Clinical Global Impression-Improvement, and hospitalization data were examined for these patients.Results: Patients whose EEG data was used for clinical treatment reported significant decreases in associated depressive symptoms (HDRS scores, overall severity of illness (Clinical Global Impression-Severity, and overall clinical global improvement (Clinical Global Impression-Improvement. This cohort also reported fewer inpatient, residential, and partial hospitalization program days following referenced-EEG compared with the two-year period prior to treatment.Conclusion: These findings are consistent with previously reported data for patients with eating disorders and suggest the need for future studies using EEG data correlated with those from other patients with similar quantitative EEG features.Keywords: eating disorders, anorexia, bulimia, depression, referenced-EEG, chart review

Proposed Standards for Variable Harmonization Documentation and Referencing: A Case Study Using QuickCharmStats 1.1

Science.gov (United States)

Winters, Kristi; Netscher, Sebastian

2016-01-01

Comparative statistical analyses often require data harmonization, yet the social sciences do not have clear operationalization frameworks that guide and homogenize variable coding decisions across disciplines. When faced with a need to harmonize variables researchers often look for guidance from various international studies that employ output harmonization, such as the Comparative Survey of Election Studies, which offer recoding structures for the same variable (e.g. marital status). More problematically there are no agreed documentation standards or journal requirements for reporting variable harmonization to facilitate a transparent replication process. We propose a conceptual and data-driven digital solution that creates harmonization documentation standards for publication and scholarly citation: QuickCharmStats 1.1. It is free and open-source software that allows for the organizing, documenting and publishing of data harmonization projects. QuickCharmStats starts at the conceptual level and its workflow ends with a variable recording syntax. It is therefore flexible enough to reflect a variety of theoretical justifications for variable harmonization. Using the socio-demographic variable ‘marital status’, we demonstrate how the CharmStats workflow collates metadata while being guided by the scientific standards of transparency and replication. It encourages researchers to publish their harmonization work by providing researchers who complete the peer review process a permanent identifier. Those who contribute original data harmonization work to their discipline can now be credited through citations. Finally, we propose peer-review standards for harmonization documentation, describe a route to online publishing, and provide a referencing format to cite harmonization projects. Although CharmStats products are designed for social scientists our adherence to the scientific method ensures our products can be used by researchers across the sciences. PMID

Student Assessment System. Domain Referenced Tests. Transportation/Automotive Mechanics. Volume II: Theory. Georgia Vocational Education Program Articulation.

Science.gov (United States)

Watkins, James F., Comp.

These written domain referenced tests (DRTs) for the area of transportation/automotive mechanics test cognitive abilities or knowledge of theory. Introductory materials describe domain referenced testing and test development. Each multiple choice test includes a domain statement, describing the behavior and content of the domain, and a test item…

CBCT images of anatomic landmarks in maxillofacial region

OpenAIRE

Mayil, Meltem; Keser, Gaye; Namdar Pekiner, Filiz

2014-01-01

Conventional radiographic techniques in dental radiology allows only 2D images of 3D structures of head and neck region. CBCT is a recent technology, is also named as dental volumetric tomography, which was developed as an alternative to conventional CT using cone beam-shaped X-ray to provide more rapid acquisition of a data set of entire maxillofacial region. CBCT has remarkable advantages such as shorter exposure time, reduced image distortion due to patient movements, dec...

DWT-SATS Based Detection of Image Region Cloning

OpenAIRE

Michael Zimba

2014-01-01

A duplicated image region may be subjected to a number of attacks such as noise addition, compression, reflection, rotation, and scaling with the intention of either merely mating it to its targeted neighborhood or preventing its detection. In this paper, we present an effective and robust method of detecting duplicated regions inclusive of those affected by the various attacks. In order to reduce the dimension of the image, the proposed algorithm firstly performs discrete wavelet transform, ...

Spatial analysis and mapping of malaria risk in Malawi using point-referenced prevalence of infection data

Directory of Open Access Journals (Sweden)

Kazembe Lawrence N

2006-09-01

Full Text Available Abstract Background Current malaria control initiatives aim at reducing malaria burden by half by the year 2010. Effective control requires evidence-based utilisation of resources. Characterizing spatial patterns of risk, through maps, is an important tool to guide control programmes. To this end an analysis was carried out to predict and map malaria risk in Malawi using empirical data with the aim of identifying areas where greatest effort should be focussed. Methods Point-referenced prevalence of infection data for children aged 1–10 years were collected from published and grey literature and geo-referenced. The model-based geostatistical methods were applied to analyze and predict malaria risk in areas where data were not observed. Topographical and climatic covariates were added in the model for risk assessment and improved prediction. A Bayesian approach was used for model fitting and prediction. Results Bivariate models showed a significant association of malaria risk with elevation, annual maximum temperature, rainfall and potential evapotranspiration (PET. However in the prediction model, the spatial distribution of malaria risk was associated with elevation, and marginally with maximum temperature and PET. The resulting map broadly agreed with expert opinion about the variation of risk in the country, and further showed marked variation even at local level. High risk areas were in the low-lying lake shore regions, while low risk was along the highlands in the country. Conclusion The map provided an initial description of the geographic variation of malaria risk in Malawi, and might help in the choice and design of interventions, which is crucial for reducing the burden of malaria in Malawi.

Lake Bathymetric DEM Shaded Relief Image

Data.gov (United States)

Minnesota Department of Natural Resources — Geo-referenced, shaded relief image of lake bathymetry classified at 5-foot depth intervals. This dataset has a cell resolution of 5 meters (occasionally 10m) as...

Comparison of bottom-track to global positioning system referenced discharges measured using an acoustic Doppler current profiler

Science.gov (United States)

Wagner, Chad R.; Mueller, David S.

2011-01-01

A negative bias in discharge measurements made with an acoustic Doppler current profiler (ADCP) can be caused by the movement of sediment on or near the streambed. The integration of a global positioning system (GPS) to track the movement of the ADCP can be used to avoid the systematic negative bias associated with a moving streambed. More than 500 discharge transects from 63 discharge measurements with GPS data were collected at sites throughout the US, Canada, and New Zealand with no moving bed to compare GPS and bottom-track-referenced discharges. Although the data indicated some statistical bias depending on site conditions and type of GPS data used, these biases were typically about 0.5% or less. An assessment of differential correction sources was limited by a lack of data collected in a range of different correction sources and different GPS receivers at the same sites. Despite this limitation, the data indicate that the use of Wide Area Augmentation System (WAAS) corrected positional data is acceptable for discharge measurements using GGA as the boat-velocity reference. The discharge data based on GPS-referenced boat velocities from the VTG data string, which does not require differential correction, were comparable to the discharges based on GPS-referenced boat velocities from the differentially-corrected GGA data string. Spatial variability of measure discharges referenced to GGA, VTG and bottom-tracking is higher near the channel banks. The spatial variability of VTG-referenced discharges is correlated with the spatial distribution of maximum Horizontal Dilution of Precision (HDOP) values and the spatial variability of GGA-referenced discharges is correlated with proximity to channel banks.

Regional Myocardial Blood Volume and Flow: First-Pass MR Imaging with Polylysine-Gd-DTPA

Science.gov (United States)

Wilke, Norbert; Kroll, Keith; Merkle, Hellmut; Wang, Ying; Ishibashi, Yukata; Xu, Ya; Zhang, Jiani; Jerosch-Herold, Michael; Mühler, Andreas; Stillman, Arthur E.; Bassingthwaighte, James B.; Bache, Robert; Ugurbil, Kamil

2010-01-01

The authors investigated the utility of an intravascular magnetic resonance (MR) contrast agent, poly-L-lysine-gadolinium diethylenetriaminepentaacetic acid (DTPA), for differentiating acutely ischemic from normally perfused myocardium with first-pass MR imaging. Hypoperfused regions, identified with microspheres, on the first-pass images displayed significantly decreased signal intensities compared with normally perfused myocardium (P < .0007). Estimates of regional myocardial blood content, obtained by measuring the ratio of areas under the signal intensity-versus-time curves in tissue regions and the left ventricular chamber, averaged 0.12 mL/g ± 0.04 (n = 35), compared with a value of 0.11 mL/g ± 0.05 measured with radiolabeled albumin in the same tissue regions. To obtain MR estimates of regional myocardial blood flow, in situ calibration curves were used to transform first-pass intensity-time curves into content-time curves for analysis with a multiple-pathway, axially distributed model. Flow estimates, obtained by automated parameter optimization, averaged 1.2 mL/min/g ± 0.5 [n = 29), compared with 1.3 mL/min/g ± 0.3 obtained with tracer microspheres in the same tissue specimens at the same time. The results represent a combination of T1-weighted first-pass imaging, intravascular relaxation agents, and a spatially distributed perfusion model to obtain absolute regional myocardial blood flow and volume. PMID:7766986

Map Coordinate Referencing and the use of GPS Datasets in Ghana ...

African Journals Online (AJOL)

Map Coordinate Referencing and the use of GPS Datasets in Ghana. ... Journal of Science and Technology (Ghana) ... systems used in Ghana (the Ghana war office system and also the Clarke1880 system) using the Bursa-Wolf model.

PC-based visualization of geographically referenced environmental data

International Nuclear Information System (INIS)

Galagan, C.; Howlett, E. Brown, A.J.

1992-01-01

Geographical information system (GIS) technology provides sophisticated data handling tools for use in oil spill response and contingency planning. ASAMAP is a software that employs a state-of-the-art graphical user interface to collect and display geographically referenced data on a personal computer. The program is easy to learn and simple to operate, facilitating data collection and visualization in an inexpensive decision support system suitable for oil spill response or any application requiring special data handling. The software can operate on a laptop computer for convenient use in the field and is mouse-driven, using buttons and screen icons to manipulate data interactively on color maps on the screen. During response to an oil spill, ASAMAP provides enhanced data capture and visualization, facilitating faster assimilation of information and a more efficient decision making process. 8 refs., 1 fig

Software for hyperspectral, joint photographic experts group (.JPG), portable network graphics (.PNG) and tagged image file format (.TIFF) segmentation

Science.gov (United States)

Bruno, L. S.; Rodrigo, B. P.; Lucio, A. de C. Jorge

2016-10-01

This paper presents a system developed by an application of a neural network Multilayer Perceptron for drone acquired agricultural image segmentation. This application allows a supervised user training the classes that will posteriorly be interpreted by neural network. These classes will be generated manually with pre-selected attributes in the application. After the attribute selection a segmentation process is made to allow the relevant information extraction for different types of images, RGB or Hyperspectral. The application allows extracting the geographical coordinates from the image metadata, geo referencing all pixels on the image. In spite of excessive memory consume on hyperspectral images regions of interest, is possible to perform segmentation, using bands chosen by user that can be combined in different ways to obtain different results.

Region-of-interest imaging in cone beam computerized tomography

International Nuclear Information System (INIS)

Tam, K.C.

1996-01-01

Imaging a sectional region within an object with a detector just big enough to cover the sectional region-of-interest is analyzed. We show that with some suitable choice of scanning configuration and with an innovative method of data combination, all the Radon data can be obtained accurately. The algorithm is mathematically exact, and requires no iterations and no additional measurements. The method can be applied to inspect portions of large industrial objects in industrial imaging, as well as to image portions of human bodies in medical diagnosis

TOTAL WOOD VOLUME ESTIMATION OF EUCALYPTUS SPECIES BY IMAGES OF LANDSAT SATELLITE

Directory of Open Access Journals (Sweden)

Elias Fernando Berra

2012-12-01

Full Text Available http://dx.doi.org/10.5902/198050987566Models relating spectral answers with biophysical parameters aim estimate variables, like wood volume, without the necessity of frequent field measurements. The objective was to develop models to estimate wood volume by Landsat 5 TM images, supported by regional forest inventory data. The image was geo-referenced and converted to spectral reflectance. After, the images-index NDVI (Normalized Difference Vegetation Index and SR (Simple Ratio was generated. The reflectance values of the bands (TM1, TM2, TM3 e TM4 and of the indices (NDVI and SR was related with the wood volume. The biggest correlation with volume was with the NDVI and SR indices. The variables selection was made by Stepwise method, which returned three regression models as significant to explain the variation in volume. Finally, the best fitted model was selected (volume = -830,95 + 46,05 (SR + 107,47 (TM2, which was applied on the Landsat image where the pixels had started to represent the estimated volume in m³/ha on the Eucalyptus sp. production units. This model, significant at 95% confidence level, explains 68% of the wood volume variation.

Regional variation in Medicare payments for medical imaging: radiologists versus nonradiologists.

Science.gov (United States)

Rosman, David A; Nsiah, Eugene; Hughes, Danny R; Duszak, Richard

2015-05-01

The purpose of this article was to study regional variation in Medicare Physician Fee Schedule (MPFS) payments for medical imaging to radiologists compared with nonradiologists. Using a 5% random sample of all Medicare enrollees, which covered approximately 2.5 million Part B beneficiaries in 2011, total professional-only, technical-only, and global MPFS spending was calculated on a state-by-state and United States Census Bureau regional basis for all Medicare Berenson-Eggers Type of Service-defined medical imaging services. Payments to radiologists versus nonradiologists were identified and variation was analyzed. Nationally, mean MPFS medical imaging spending per Medicare beneficiary was $207.17 ($95.71 [46.2%] to radiologists vs $111.46 [53.8%] to nonradiologists). Of professional-only (typically interpretation) payments, 20.6% went to nonradiologists. Of technical-only (typically owned equipment) payments, 84.9% went to nonradiologists. Of global (both professional and technical) payments, 70.1% went to nonradiologists. The percentage of MPFS medical imaging spending on nonradiologists ranged from 32% (Minnesota) to 69.5% (South Carolina). The percentage of MPFS payments for medical imaging to nonradiologists exceeded those to radiologists in 58.8% of states. The relative percentage of MPFS payments to nonradiologists was highest in the South (58.5%) and lowest in the Northeast (48.0%). Nationally, 53.8% of MPFS payments for medical imaging services are made to nonradiologists, who claim a majority of MPFS payments in most states dominated by noninterpretive payments. This majority spending on nonradiologists may have implications in bundled and capitated payment models for radiology services. Medical imaging payment policy initiatives must consider the roles of all provider groups and associated regional variation.

An age estimation method using brain local features for T1-weighted images.

Science.gov (United States)

Kondo, Chihiro; Ito, Koichi; Kai Wu; Sato, Kazunori; Taki, Yasuyuki; Fukuda, Hiroshi; Aoki, Takafumi

2015-08-01

Previous statistical analysis studies using large-scale brain magnetic resonance (MR) image databases have examined that brain tissues have age-related morphological changes. This fact indicates that one can estimate the age of a subject from his/her brain MR image by evaluating morphological changes with healthy aging. This paper proposes an age estimation method using local features extracted from T1-weighted MR images. The brain local features are defined by volumes of brain tissues parcellated into local regions defined by the automated anatomical labeling atlas. The proposed method selects optimal local regions to improve the performance of age estimation. We evaluate performance of the proposed method using 1,146 T1-weighted images from a Japanese MR image database. We also discuss the medical implication of selected optimal local regions.

Standardization of a geo-referenced fishing data set for the Indian Ocean bigeye tuna, Thunnus obesus (1952-2014)

Science.gov (United States)

Wibawa, Teja A.; Lehodey, Patrick; Senina, Inna

2017-02-01

Geo-referenced catch and fishing effort data of the bigeye tuna fisheries in the Indian Ocean over 1952-2014 were analyzed and standardized to facilitate population dynamics modeling studies. During this 62-year historical period of exploitation, many changes occurred both in the fishing techniques and the monitoring of activity. This study includes a series of processing steps used for standardization of spatial resolution, conversion and standardization of catch and effort units, raising of geo-referenced catch into nominal catch level, screening and correction of outliers, and detection of major catchability changes over long time series of fishing data, i.e., the Japanese longline fleet operating in the tropical Indian Ocean. A total of 30 fisheries were finally determined from longline, purse seine and other-gears data sets, from which 10 longline and 4 purse seine fisheries represented 96 % of the whole historical geo-referenced catch. Nevertheless, one-third of total nominal catch is still not included due to a total lack of geo-referenced information and would need to be processed separately, accordingly to the requirements of the study. The geo-referenced records of catch, fishing effort and associated length frequency samples of all fisheries are available at PANGAEA.864154" target="_blank">doi:10.1594/PANGAEA.864154.

Scalable Integrated Region-Based Image Retrieval Using IRM and Statistical Clustering.

Science.gov (United States)

Wang, James Z.; Du, Yanping

Statistical clustering is critical in designing scalable image retrieval systems. This paper presents a scalable algorithm for indexing and retrieving images based on region segmentation. The method uses statistical clustering on region features and IRM (Integrated Region Matching), a measure developed to evaluate overall similarity between images…

Region-Based Image Retrieval Using an Object Ontology and Relevance Feedback

Directory of Open Access Journals (Sweden)

Kompatsiaris Ioannis

2004-01-01

Full Text Available An image retrieval methodology suited for search in large collections of heterogeneous images is presented. The proposed approach employs a fully unsupervised segmentation algorithm to divide images into regions and endow the indexing and retrieval system with content-based functionalities. Low-level descriptors for the color, position, size, and shape of each region are subsequently extracted. These arithmetic descriptors are automatically associated with appropriate qualitative intermediate-level descriptors, which form a simple vocabulary termed object ontology. The object ontology is used to allow the qualitative definition of the high-level concepts the user queries for (semantic objects, each represented by a keyword and their relations in a human-centered fashion. When querying for a specific semantic object (or objects, the intermediate-level descriptor values associated with both the semantic object and all image regions in the collection are initially compared, resulting in the rejection of most image regions as irrelevant. Following that, a relevance feedback mechanism, based on support vector machines and using the low-level descriptors, is invoked to rank the remaining potentially relevant image regions and produce the final query results. Experimental results and comparisons demonstrate, in practice, the effectiveness of our approach.

Region Templates: Data Representation and Management for High-Throughput Image Analysis.

Science.gov (United States)

Teodoro, George; Pan, Tony; Kurc, Tahsin; Kong, Jun; Cooper, Lee; Klasky, Scott; Saltz, Joel

2014-12-01

We introduce a region template abstraction and framework for the efficient storage, management and processing of common data types in analysis of large datasets of high resolution images on clusters of hybrid computing nodes. The region template abstraction provides a generic container template for common data structures, such as points, arrays, regions, and object sets, within a spatial and temporal bounding box. It allows for different data management strategies and I/O implementations, while providing a homogeneous, unified interface to applications for data storage and retrieval. A region template application is represented as a hierarchical dataflow in which each computing stage may be represented as another dataflow of finer-grain tasks. The execution of the application is coordinated by a runtime system that implements optimizations for hybrid machines, including performance-aware scheduling for maximizing the utilization of computing devices and techniques to reduce the impact of data transfers between CPUs and GPUs. An experimental evaluation on a state-of-the-art hybrid cluster using a microscopy imaging application shows that the abstraction adds negligible overhead (about 3%) and achieves good scalability and high data transfer rates. Optimizations in a high speed disk based storage implementation of the abstraction to support asynchronous data transfers and computation result in an application performance gain of about 1.13×. Finally, a processing rate of 11,730 4K×4K tiles per minute was achieved for the microscopy imaging application on a cluster with 100 nodes (300 GPUs and 1,200 CPU cores). This computation rate enables studies with very large datasets.

Identifying regions of interest in medical images using self-organizing maps.

Science.gov (United States)

Teng, Wei-Guang; Chang, Ping-Lin

2012-10-01

Advances in data acquisition, processing and visualization techniques have had a tremendous impact on medical imaging in recent years. However, the interpretation of medical images is still almost always performed by radiologists. Developments in artificial intelligence and image processing have shown the increasingly great potential of computer-aided diagnosis (CAD). Nevertheless, it has remained challenging to develop a general approach to process various commonly used types of medical images (e.g., X-ray, MRI, and ultrasound images). To facilitate diagnosis, we recommend the use of image segmentation to discover regions of interest (ROI) using self-organizing maps (SOM). We devise a two-stage SOM approach that can be used to precisely identify the dominant colors of a medical image and then segment it into several small regions. In addition, by appropriately conducting the recursive merging steps to merge smaller regions into larger ones, radiologists can usually identify one or more ROIs within a medical image.

Two self-referencing methods for the measurement of beam spot position

Energy Technology Data Exchange (ETDEWEB)

Nyiri, Balazs J.; Smale, Jason R.; Gerig, Lee H. [Ottawa Hospital Cancer Centre, Ottawa K1H 8L6 (Canada) and Faculty of Medicine, University of Ottawa, Ottawa K1H 8M5 (Canada); Elekta Canada, Ottawa, Ontario K1Y 1Z3 (Canada); Ottawa Hospital Cancer Centre, Ottawa K1H 8L6 (Canada); Department of Physics, Carleton University, Ottawa K1S 5B6 (Canada) and Faculty of Medicine, University of Ottawa, Ottawa K1H 8M5 (Canada)

2012-12-15

Purpose: Two quantitative methods of measuring electron beam spot position with respect to the collimator axis of rotation (CAOR) are described. Methods: Method 1 uses a cylindrical ion chamber (IC) mounted on a jig corotational with the collimator making the relationship among the chamber, jaws, and CAOR fixed and independent of collimator angle. A jaw parallel to the IC axis is set to zero and the IC position adjusted so that the IC signal is approximately 50% of the open field value, providing a large dose gradient in the region of the IC. The cGy/MU value is measured as a function of collimator rotation, e.g., every 30 Degree-Sign . If the beam spot does not lie on the CAOR, the signal from the ion chamber will vary with collimator rotation. Based on a measured spatial sensitivity, the distance of the beam spot from the CAOR can be calculated from the IC signal variation with rotation. The 2nd method is image based. Two stainless steel rods, 3 mm in diameter, are mounted to a jig attached to the Linac collimator. The rods, offset from the CAOR, lay in different planes normal to the CAOR, one at 158 cm SSD and the other at 70 cm SSD. As the collimator rotates the rods move tangent along an envelope circle, the centers of which are on the CAOR in their respective planes. Three images, each at a different collimator rotation, containing the shadows of both rods, are acquired on the Linac EPID. At each angle the shadow of the rods on the EPID defines lines tangent to the projection of the envelope circles. From these the authors determine the projected centers of the two circles at different heights. From the distance of these two points using the two heights and the source to EPID distance, the authors calculate the distance of the beam spot from the CAOR. Measurements with all two techniques were performed on an Elekta Linac. Measurements were performed with the beam spot in nominal clinical position and in a deliberately offset position. Measurements were also

Near Real-Time Dissemination of Geo-Referenced Imagery by an Enterprise Server

National Research Council Canada - National Science Library

Brown, Alison; Gilbert, Chris; Holland, Heather; Lu, Yan

2006-01-01

.... The payload is connected through a data link to a ground-based server that can process the georegistered data in near-real-time using our GeoReferenced Information Manager (GRIM) Enterprise Server...

Segmenting high-frequency intracardiac ultrasound images of myocardium into infarcted, ischemic, and normal regions.

Science.gov (United States)

Hao, X; Bruce, C J; Pislaru, C; Greenleaf, J F

2001-12-01

Segmenting abnormal from normal myocardium using high-frequency intracardiac echocardiography (ICE) images presents new challenges for image processing. Gray-level intensity and texture features of ICE images of myocardium with the same structural/perfusion properties differ. This significant limitation conflicts with the fundamental assumption on which existing segmentation techniques are based. This paper describes a new seeded region growing method to overcome the limitations of the existing segmentation techniques. Three criteria are used for region growing control: 1) Each pixel is merged into the globally closest region in the multifeature space. 2) "Geographic similarity" is introduced to overcome the problem that myocardial tissue, despite having the same property (i.e., perfusion status), may be segmented into several different regions using existing segmentation methods. 3) "Equal opportunity competence" criterion is employed making results independent of processing order. This novel segmentation method is applied to in vivo intracardiac ultrasound images using pathology as the reference method for the ground truth. The corresponding results demonstrate that this method is reliable and effective.

Ten Issues in Criterion-Referenced Testing: A Response to Commonly Heard Criticisms.

Science.gov (United States)

Curlette, William L.; Stallings, William M.

1979-01-01

The 10 criticisms of criterion-referenced tests addressed in this paper are: the domains tested; pedagogical influence; difficulty of items; cumbersome reports; reliability; arbitrary criteria; local objectives; labeling; predictive validity; and repeated testing. (SJL)

PLUME–FEATHER, Referencing and Finding Software for Research and Education

International Nuclear Information System (INIS)

Hoffmann, Dirk; Romier, Geneviève

2012-01-01

PLUME-FEATHER is a non-profit project created to Promote economicaL, Useful and Maintained softwarE For the Higher Education And THE Research communities. The site references software, mainly Free/Libre Open Source Software (FLOSS) from French universities and national research organisations, (CNRS, INRA…), laboratories or departments as well as other FLOSS software used and evaluated by users within these institutions. Each software is represented by a reference card, which describes origin, aim, installation, cost (if applicable) and user experience from the point of view of an academic user for academic users. Presently over 1000 programs are referenced on PLUME. Although the server is maintained by a french institution, it is completely open to international contributions in the academic domainb. All contained and validated contents are visible to anonymous public, whereas registered users can contribute, starting with comments on single software reference cards up to help with the organisation and presentation of the referenced software products. This first presentation is call for (further) contributions from the HEP community.

NMR imaging of the head-neck region. Topography of function - clinical findings - imaging and spectroscopy

International Nuclear Information System (INIS)

Vogl, T.J.

1991-01-01

The book on nmr imaging in the head-neck region offers, on a total of 221 pages, 344 detailed representations with 141 figures and 44 tables. It provides information as to the relevant topography of function, presents clinical findings, explains imaging characteristics and also takes account of spectroscopic procedures. The multifarious methods of investigation are described and discussed in connection with the differential diagnoses. A score of suitable diagnostic measures is assigned to each region of examination. The method's value is assessed against that of other imaging techniques. (orig.) [de

[Examination of upper abdominal region in high spatial resolution diffusion-weighted imaging using 3-Tesla MRI].

Science.gov (United States)

Terada, Masaki; Matsushita, Hiroki; Oosugi, Masanori; Inoue, Kazuyasu; Yaegashi, Taku; Anma, Takeshi

2009-03-20

The advantage of the higher signal-to-noise ratio (SNR) of 3-Tesla magnetic resonance imaging (3-Tesla) has the possibility of contributing to the improvement of high spatial resolution without causing image deterioration. In this study, we compared SNR and the apparent diffusion coefficient (ADC) value with 3-Tesla as the condition in the diffusion-weighted image (DWI) parameter of the 1.5-Tesla magnetic resonance imaging (1.5-Tesla) and we examined the high spatial resolution images in the imaging method [respiratory-triggering (RT) method and breath free (BF) method] and artifact (motion and zebra) in the upper abdominal region of DWI at 3-Tesla. We have optimized scan parameters based on phantom and in vivo study. As a result, 3-Tesla was able to obtain about 1.5 times SNR in comparison with the 1.5-Tesla, ADC value had few differences. Moreover, the RT method was effective in correcting the influence of respiratory movement in comparison with the BF method, and image improvement by the effective acquisition of SNR and reduction of the artifact were provided. Thus, DWI of upper abdominal region was a useful sequence for the high spatial resolution in 3-Tesla.

Direct observation of the leakage current in epitaxial diamond Schottky barrier devices by conductive-probe atomic force microscopy and Raman imaging

OpenAIRE

Alvarez, Jose; Boutchich, M.; Kleider, J. P.; Teraji, T.; Koide, Y.

2014-01-01

The origin of the high leakage current measured in several vertical-type diamond Schottky devices is conjointly investigated by conducting probe atomic force microscopy (CP-AFM) and confocal micro-Raman/Photoluminescence (PL) imaging analysis. Local areas characterized by a strong decrease of the local resistance (5-6 orders of magnitude drop) with respect to their close surrounding have been identified in several different regions of the sample surface. The same local areas, also referenced ...

Cloud solution for histopathological image analysis using region of interest based compression.

Science.gov (United States)

Kanakatte, Aparna; Subramanya, Rakshith; Delampady, Ashik; Nayak, Rajarama; Purushothaman, Balamuralidhar; Gubbi, Jayavardhana

2017-07-01

Recent technological gains have led to the adoption of innovative cloud based solutions in medical imaging field. Once the medical image is acquired, it can be viewed, modified, annotated and shared on many devices. This advancement is mainly due to the introduction of Cloud computing in medical domain. Tissue pathology images are complex and are normally collected at different focal lengths using a microscope. The single whole slide image contains many multi resolution images stored in a pyramidal structure with the highest resolution image at the base and the smallest thumbnail image at the top of the pyramid. Highest resolution image will be used for tissue pathology diagnosis and analysis. Transferring and storing such huge images is a big challenge. Compression is a very useful and effective technique to reduce the size of these images. As pathology images are used for diagnosis, no information can be lost during compression (lossless compression). A novel method of extracting the tissue region and applying lossless compression on this region and lossy compression on the empty regions has been proposed in this paper. The resulting compression ratio along with lossless compression on tissue region is in acceptable range allowing efficient storage and transmission to and from the Cloud.

Renewable Resources: a national catalog of model projects. Volume 1. Northeast Solar Energy Center Region

Energy Technology Data Exchange (ETDEWEB)

None

1980-07-01

This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Northeast Solar Energy Center Region. (WHK).

Estimation of regional lung expansion via 3D image registration

Science.gov (United States)

Pan, Yan; Kumar, Dinesh; Hoffman, Eric A.; Christensen, Gary E.; McLennan, Geoffrey; Song, Joo Hyun; Ross, Alan; Simon, Brett A.; Reinhardt, Joseph M.

2005-04-01

A method is described to estimate regional lung expansion and related biomechanical parameters using multiple CT images of the lungs, acquired at different inflation levels. In this study, the lungs of two sheep were imaged utilizing a multi-detector row CT at different lung inflations in the prone and supine positions. Using the lung surfaces and the airway branch points for guidance, a 3D inverse consistent image registration procedure was used to match different lung volumes at each orientation. The registration was validated using a set of implanted metal markers. After registration, the Jacobian of the deformation field was computed to express regional expansion or contraction. The regional lung expansion at different pressures and different orientations are compared.

Paradox image: a noninvasive index of regional left-ventricular dyskinesis

International Nuclear Information System (INIS)

Holman, B.L.; Wynne, J.; Idoine, J.; Zielonka, J.; Neill, J.

1979-01-01

The paradox image, a functional image of regional dyskinesis derived from the equilibrium (gated) radionuclide ventriculogram, was constructed by subtracting the background-corrected end-diastolic frame from the background-corrected end-systolic frame. In 11 patients showing dyskinesis by contrast ventriculography, the percentage of left-ventricular picture elements containing paradox ranged from 3.6 to 55.6% (21.44% +- 4.45 s.e.m.). In 11 patients with normokinesis and in eight patients with hypookinesis by contrast ventriculography, the left-ventricular picture elements demonstrating paradox were less than 1.1% in all cases. In nine patients with akinesis, the percentage of left-ventricular picture elements containing paradox was 2.05% +- 0.96 s.e.m. and was less than 2% in seven patients. There was also an excellent agreement between the location of dyskinesis on the paradox image and that by contrast ventriculography. The paradox image is a sensitive indicator of left-ventricular dyskinesis and should be useful in the evaluation of patients with suspected left-ventricular asynergy

A High-Resolution Tile-Based Approach for Classifying Biological Regions in Whole-Slide Histopathological Images.

Science.gov (United States)

Hoffman, R A; Kothari, S; Phan, J H; Wang, M D

Computational analysis of histopathological whole slide images (WSIs) has emerged as a potential means for improving cancer diagnosis and prognosis. However, an open issue relating to the automated processing of WSIs is the identification of biological regions such as tumor, stroma, and necrotic tissue on the slide. We develop a method for classifying WSI portions (512x512-pixel tiles) into biological regions by (1) extracting a set of 461 image features from each WSI tile, (2) optimizing tile-level prediction models using nested cross-validation on a small (600 tile) manually annotated tile-level training set, and (3) validating the models against a much larger (1.7x10 6 tile) data set for which ground truth was available on the whole-slide level. We calculated the predicted prevalence of each tissue region and compared this prevalence to the ground truth prevalence for each image in an independent validation set. Results show significant correlation between the predicted (using automated system) and reported biological region prevalences with p < 0.001 for eight of nine cases considered.

Adaptions of ArcGIS' Linear Referencing System to the Coastal Environment

DEFF Research Database (Denmark)

Balstrøm, Thomas

2008-01-01

For many years it has been problematic to store information for the coastal environment in a GIS. However, a system named "Linear referencing System" based upon a dynamic segmentation principle implemented in ESRIs ArcGIS 9 software has now made it possible to store and analyze information...

Cranial magnetic resonance imaging

International Nuclear Information System (INIS)

Elster, A.D.

1988-01-01

Cranial Magnetic Resonance Imaging is comprehensive, well structured, and well written. The material is current and well referenced. The illustrations are good and complement the text well. The overall quality of publication is above average. The greatest attribute of the book is its readability. The author demonstrates ample skill in making complex subjects, such as MR physics and imaging of cerebral hemorrhage, easy to understand. The book closes with a detailed atlas on the anatomic appearance of the brain on MR images in the axial, coronal, and sagittal planes

SENTINEL-2 LEVEL 1 PRODUCTS AND IMAGE PROCESSING PERFORMANCES

Directory of Open Access Journals (Sweden)

S. J. Baillarin

2012-07-01

. The stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m and multi-temporal (better than 0.3 pixels cases. Then, the prototyped image processing techniques (both radiometric and geometric will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …. Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

SENTINEL-2 Level 1 Products and Image Processing Performances

Science.gov (United States)

Baillarin, S. J.; Meygret, A.; Dechoz, C.; Petrucci, B.; Lacherade, S.; Tremas, T.; Isola, C.; Martimort, P.; Spoto, F.

2012-07-01

stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m) and multi-temporal (better than 0.3 pixels) cases. Then, the prototyped image processing techniques (both radiometric and geometric) will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …). Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

The regulatory function of social referencing in preschoolers with Down syndrome or Williams syndrome

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Thurman Angela John

2013-02-01

Full Text Available Abstract Background An important developmental task is to learn to recognize another person as a source of information and to utilize this information as a method of learning about the surrounding world. This socially guided form of learning, referred to as social referencing, is critical for the development of children’s understanding of other people, themselves and their surrounding world. In the present project, the regulatory function of social referencing was examined in two genetic disorders that are characterized by differing patterns of socio-cognitive development: Down syndrome (DS and Williams syndrome (WS. Methods Participants were 20 children with DS and 20 children with WS aged 42 to 71 months, matched on chronological age and gender. Each child participated in four studies: one study in which we examined performance in a social referencing paradigm and three studies in which we considered performance on tasks designed to tap each of three component abilities (initiating eye contact, gaze following and emotional responsivity important for success in social referencing. Results The majority of children in both groups demonstrated positive behavioral responses regarding the stimulus in the Social Referencing task when the adult communicated a joyful message but did not regulate their own behavior in accordance with the adult’s expression of fear. Between-group differences were observed in both conditions, with most differences indicating more advanced socio-communicative competence for children with DS than for children with WS even though the overall intellectual abilities and receptive language abilities of the children with WS were significantly higher than were those of the children with DS. The results of follow-up studies indicated that children with DS were more likely to initiate eye contact (unsolicited and to follow another person’s gaze in triadic situations than were children with WS. Neither group regulated their

The evolutionary rates of HCV estimated with subtype 1a and 1b sequences over the ORF length and in different genomic regions.

Directory of Open Access Journals (Sweden)

Manqiong Yuan

Full Text Available Considerable progress has been made in the HCV evolutionary analysis, since the software BEAST was released. However, prior information, especially the prior evolutionary rate, which plays a critical role in BEAST analysis, is always difficult to ascertain due to various uncertainties. Providing a proper prior HCV evolutionary rate is thus of great importance.176 full-length sequences of HCV subtype 1a and 144 of 1b were assembled by taking into consideration the balance of the sampling dates and the even dispersion in phylogenetic trees. According to the HCV genomic organization and biological functions, each dataset was partitioned into nine genomic regions and two routinely amplified regions. A uniform prior rate was applied to the BEAST analysis for each region and also the entire ORF. All the obtained posterior rates for 1a are of a magnitude of 10(-3 substitutions/site/year and in a bell-shaped distribution. Significantly lower rates were estimated for 1b and some of the rate distribution curves resulted in a one-sided truncation, particularly under the exponential model. This indicates that some of the rates for subtype 1b are less accurate, so they were adjusted by including more sequences to improve the temporal structure.Among the various HCV subtypes and genomic regions, the evolutionary patterns are dissimilar. Therefore, an applied estimation of the HCV epidemic history requires the proper selection of the rate priors, which should match the actual dataset so that they can fit for the subtype, the genomic region and even the length. By referencing the findings here, future evolutionary analysis of the HCV subtype 1a and 1b datasets may become more accurate and hence prove useful for tracing their patterns.

A REGION-BASED MULTI-SCALE APPROACH FOR OBJECT-BASED IMAGE ANALYSIS

Directory of Open Access Journals (Sweden)

T. Kavzoglu

2016-06-01

Full Text Available Within the last two decades, object-based image analysis (OBIA considering objects (i.e. groups of pixels instead of pixels has gained popularity and attracted increasing interest. The most important stage of the OBIA is image segmentation that groups spectrally similar adjacent pixels considering not only the spectral features but also spatial and textural features. Although there are several parameters (scale, shape, compactness and band weights to be set by the analyst, scale parameter stands out the most important parameter in segmentation process. Estimating optimal scale parameter is crucially important to increase the classification accuracy that depends on image resolution, image object size and characteristics of the study area. In this study, two scale-selection strategies were implemented in the image segmentation process using pan-sharped Qickbird-2 image. The first strategy estimates optimal scale parameters for the eight sub-regions. For this purpose, the local variance/rate of change (LV-RoC graphs produced by the ESP-2 tool were analysed to determine fine, moderate and coarse scales for each region. In the second strategy, the image was segmented using the three candidate scale values (fine, moderate, coarse determined from the LV-RoC graph calculated for whole image. The nearest neighbour classifier was applied in all segmentation experiments and equal number of pixels was randomly selected to calculate accuracy metrics (overall accuracy and kappa coefficient. Comparison of region-based and image-based segmentation was carried out on the classified images and found that region-based multi-scale OBIA produced significantly more accurate results than image-based single-scale OBIA. The difference in classification accuracy reached to 10% in terms of overall accuracy.

Partial Fingerprint Image Enhancement using Region Division Technique and Morphological Transform

International Nuclear Information System (INIS)

Ahmad, A.; Arshad, I.; Raja, G.

2015-01-01

Fingerprints are the most renowned biometric trait for identification and verification. The quality of fingerprint image plays a vital role in feature extraction and matching. Existing algorithms work well for good quality fingerprint images and fail for partial fingerprint images as they are obtained from excessively dry fingers or affected by disease resulting in broken ridges. We propose an algorithm to enhance partial fingerprint images using morphological operatins with region division technique. The proposed method divides low quality image into six regions from top to bottom. Morphological operations choose an appropriate Structuring Element (SE) that joins broken ridges and thus enhance the image for further processing. The proposed method uses SE line with suitable angle theta and radius r in each region based on the orientation of the ridges. The algorithm is applied to 14 low quality fingerprint images from FVC-2002 database. Experimental results show that percentage accuracy has been improved using the proposed algorithm. The manual markup has been reduced and accuracy of 76.16% with Equal Error Rate (EER) of 3.16% is achieved. (author)

Surface regions of illusory images are detected with a slower processing speed than those of luminance-defined images.

Science.gov (United States)

Mihaylova, Milena; Manahilov, Velitchko

2010-11-24

Research has shown that the processing time for discriminating illusory contours is longer than for real contours. We know, however, little whether the visual processes, associated with detecting regions of illusory surfaces, are also slower as those responsible for detecting luminance-defined images. Using a speed-accuracy trade-off (SAT) procedure, we measured accuracy as a function of processing time for detecting illusory Kanizsa-type and luminance-defined squares embedded in 2D static luminance noise. The data revealed that the illusory images were detected at slower processing speed than the real images, while the points in time, when accuracy departed from chance, were not significantly different for both stimuli. The classification images for detecting illusory and real squares showed that observers employed similar detection strategies using surface regions of the real and illusory squares. The lack of significant differences between the x-intercepts of the SAT functions for illusory and luminance-modulated stimuli suggests that the detection of surface regions of both images could be based on activation of a single mechanism (the dorsal magnocellular visual pathway). The slower speed for detecting illusory images as compared to luminance-defined images could be attributed to slower processes of filling-in of regions of illusory images within the dorsal pathway.

Using GRAPPA to improve autocalibrated coil sensitivity estimation for the SENSE family of parallel imaging reconstruction algorithms.

Science.gov (United States)

Hoge, W Scott; Brooks, Dana H

2008-08-01

Two strategies are widely used in parallel MRI to reconstruct subsampled multicoil image data. SENSE and related methods employ explicit receiver coil spatial response estimates to reconstruct an image. In contrast, coil-by-coil methods such as GRAPPA leverage correlations among the acquired multicoil data to reconstruct missing k-space lines. In self-referenced scenarios, both methods employ Nyquist-rate low-frequency k-space data to identify the reconstruction parameters. Because GRAPPA does not require explicit coil sensitivities estimates, it needs considerably fewer autocalibration signals than SENSE. However, SENSE methods allow greater opportunity to control reconstruction quality though regularization and thus may outperform GRAPPA in some imaging scenarios. Here, we employ GRAPPA to improve self-referenced coil sensitivity estimation in SENSE and related methods using very few auto-calibration signals. This enables one to leverage each methods' inherent strength and produce high quality self-referenced SENSE reconstructions. (c) 2008 Wiley-Liss, Inc.

Validation of a Criterion Referenced Test for Young Handicapped Children: PIPER.

Science.gov (United States)

Strum, Irene; Shapiro, Madelaine

The purpose of this study was to validate the Prescriptive Instructional Program for Educational Readiness (PIPER) for utilization as a criterion referenced test (CRT) among learning disabled children. The program consisted of behavioral objectives and diagnostic and/or mastery tasks and activities for each objective in the area of gross motor…

Regional SAR Image Segmentation Based on Fuzzy Clustering with Gamma Mixture Model

Science.gov (United States)

Li, X. L.; Zhao, Q. H.; Li, Y.

2017-09-01

Most of stochastic based fuzzy clustering algorithms are pixel-based, which can not effectively overcome the inherent speckle noise in SAR images. In order to deal with the problem, a regional SAR image segmentation algorithm based on fuzzy clustering with Gamma mixture model is proposed in this paper. First, initialize some generating points randomly on the image, the image domain is divided into many sub-regions using Voronoi tessellation technique. Each sub-region is regarded as a homogeneous area in which the pixels share the same cluster label. Then, assume the probability of the pixel to be a Gamma mixture model with the parameters respecting to the cluster which the pixel belongs to. The negative logarithm of the probability represents the dissimilarity measure between the pixel and the cluster. The regional dissimilarity measure of one sub-region is defined as the sum of the measures of pixels in the region. Furthermore, the Markov Random Field (MRF) model is extended from pixels level to Voronoi sub-regions, and then the regional objective function is established under the framework of fuzzy clustering. The optimal segmentation results can be obtained by the solution of model parameters and generating points. Finally, the effectiveness of the proposed algorithm can be proved by the qualitative and quantitative analysis from the segmentation results of the simulated and real SAR images.

Magnetic resonance imaging in the cranio-cervical region

International Nuclear Information System (INIS)

Koschorek, F.; Jensen, H.P.; Terwey, B.

1987-01-01

Since the introduction of nuclear magnetic resonance imaging (NMR) in the neurosurgical and neurological diagnostic this new imaging modality has shown to be of high diagnostic value - especially in disease process of the cranio-vertebral junction. Other imaging moralities such as x-ray CT and myelography are of inferior quality as the images are degraded by bone artifacts and superposition of other structures. NMR can reveal many aspects of the cranio-vertebral region in a single examination without artifacts from surrounding structures. A further improvement of NMR is the introduction of para-magnetic agents, such as gadolinium-DTPA, as it increases the specifity by dynamic magnetic resonance imaging. The authors present a review of their clinical experience

A region-based segmentation method for ultrasound images in HIFU therapy

International Nuclear Information System (INIS)

Zhang, Dong; Liu, Yu; Yang, Yan; Xu, Menglong; Yan, Yu; Qin, Qianqing

2016-01-01

Purpose: Precisely and efficiently locating a tumor with less manual intervention in ultrasound-guided high-intensity focused ultrasound (HIFU) therapy is one of the keys to guaranteeing the therapeutic result and improving the efficiency of the treatment. The segmentation of ultrasound images has always been difficult due to the influences of speckle, acoustic shadows, and signal attenuation as well as the variety of tumor appearance. The quality of HIFU guidance images is even poorer than that of conventional diagnostic ultrasound images because the ultrasonic probe used for HIFU guidance usually obtains images without making contact with the patient’s body. Therefore, the segmentation becomes more difficult. To solve the segmentation problem of ultrasound guidance image in the treatment planning procedure for HIFU therapy, a novel region-based segmentation method for uterine fibroids in HIFU guidance images is proposed. Methods: Tumor partitioning in HIFU guidance image without manual intervention is achieved by a region-based split-and-merge framework. A new iterative multiple region growing algorithm is proposed to first split the image into homogenous regions (superpixels). The features extracted within these homogenous regions will be more stable than those extracted within the conventional neighborhood of a pixel. The split regions are then merged by a superpixel-based adaptive spectral clustering algorithm. To ensure the superpixels that belong to the same tumor can be clustered together in the merging process, a particular construction strategy for the similarity matrix is adopted for the spectral clustering, and the similarity matrix is constructed by taking advantage of a combination of specifically selected first-order and second-order texture features computed from the gray levels and the gray level co-occurrence matrixes, respectively. The tumor region is picked out automatically from the background regions by an algorithm according to a priori

A region-based segmentation method for ultrasound images in HIFU therapy

Energy Technology Data Exchange (ETDEWEB)

Zhang, Dong, E-mail: dongz@whu.edu.cn; Liu, Yu; Yang, Yan; Xu, Menglong; Yan, Yu [School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Qin, Qianqing [State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430072 (China)

2016-06-15

Purpose: Precisely and efficiently locating a tumor with less manual intervention in ultrasound-guided high-intensity focused ultrasound (HIFU) therapy is one of the keys to guaranteeing the therapeutic result and improving the efficiency of the treatment. The segmentation of ultrasound images has always been difficult due to the influences of speckle, acoustic shadows, and signal attenuation as well as the variety of tumor appearance. The quality of HIFU guidance images is even poorer than that of conventional diagnostic ultrasound images because the ultrasonic probe used for HIFU guidance usually obtains images without making contact with the patient’s body. Therefore, the segmentation becomes more difficult. To solve the segmentation problem of ultrasound guidance image in the treatment planning procedure for HIFU therapy, a novel region-based segmentation method for uterine fibroids in HIFU guidance images is proposed. Methods: Tumor partitioning in HIFU guidance image without manual intervention is achieved by a region-based split-and-merge framework. A new iterative multiple region growing algorithm is proposed to first split the image into homogenous regions (superpixels). The features extracted within these homogenous regions will be more stable than those extracted within the conventional neighborhood of a pixel. The split regions are then merged by a superpixel-based adaptive spectral clustering algorithm. To ensure the superpixels that belong to the same tumor can be clustered together in the merging process, a particular construction strategy for the similarity matrix is adopted for the spectral clustering, and the similarity matrix is constructed by taking advantage of a combination of specifically selected first-order and second-order texture features computed from the gray levels and the gray level co-occurrence matrixes, respectively. The tumor region is picked out automatically from the background regions by an algorithm according to a priori

Imaging regional metabolic changes in the ischemic rat heart in vivo using hyperpolarized(1-13C)Pyruvate

DEFF Research Database (Denmark)

Lauritzen, Mette Hauge; Magnusson, Peter; Laustsen, Christoffer

2017-01-01

in the in vivo rat heart in an open-chest model of ischemia reperfusion. Hyperpolarized MRI enables new possibilities for evaluating changes in cardiac metabolism noninvasively and in real time, which potentially could be used for research to evaluate new treatments and metabolic interventions for myocardial......We evaluated the use of hyperpolarized 13C magnetic resonance imaging (MRI) in an open-chest rat model of myocardial infarction to image regional changes in myocardial metabolism. In total, 10 rats were examined before and after 30 minutes of occlusion of the left anterior descending coronary...

Fiducial-based registration with a touchable region model.

Science.gov (United States)

Kim, Sungmin; Kazanzides, Peter

2017-02-01

Image-guided surgery requires registration between an image coordinate system and an intraoperative coordinate system that is typically referenced to a tracking device. In fiducial-based registration methods, this is achieved by localizing points (fiducials) in each coordinate system. Often, both localizations are performed manually, first by picking a fiducial point in the image and then by using a hand-held tracked pointer to physically touch the corresponding fiducial on the patient. These manual procedures introduce localization error that is user-dependent and can significantly decrease registration accuracy. Thus, there is a need for a registration method that is tolerant of imprecise fiducial localization in the preoperative and intraoperative phases. We propose the iterative closest touchable point (ICTP) registration framework, which uses model-based localization and a touchable region model. This method consists of three stages: (1) fiducial marker localization in image space, using a fiducial marker model, (2) initial registration with paired-point registration, and (3) fine registration based on the iterative closest point method. We perform phantom experiments with a fiducial marker design that is commonly used in neurosurgery. The results demonstrate that ICTP can provide accuracy improvements compared to the standard paired-point registration method that is widely used for surgical navigation and surgical robot systems, especially in cases where the surgeon introduces large localization errors. The results demonstrate that the proposed method can reduce the effect of the surgeon's localization performance on the accuracy of registration, thereby producing more consistent and less user-dependent registration outcomes.

Region-based Image Segmentation by Watershed Partition and DCT Energy Compaction

Directory of Open Access Journals (Sweden)

Chi-Man Pun

2012-02-01

Full Text Available An image segmentation approach by improved watershed partition and DCT energy compaction has been proposed in this paper. The proposed energy compaction, which expresses the local texture of an image area, is derived by exploiting the discrete cosine transform. The algorithm is a hybrid segmentation technique which is composed of three stages. First, the watershed transform is utilized by preprocessing techniques: edge detection and marker in order to partition the image in to several small disjoint patches, while the region size, mean and variance features are used to calculate region cost for combination. Then in the second merging stage the DCT transform is used for energy compaction which is a criterion for texture comparison and region merging. Finally the image can be segmented into several partitions. The experimental results show that the proposed approach achieved very good segmentation robustness and efficiency, when compared to other state of the art image segmentation algorithms and human segmentation results.

Spatial analysis of instream nitrogen loads and factors controlling nitrogen delivery to streams in the southeastern United States using spatially referenced regression on watershed attributes (SPARROW) and regional classification frameworks

Science.gov (United States)

Hoos, Anne B.; McMahon, Gerard

2009-01-01

Understanding how nitrogen transport across the landscape varies with landscape characteristics is important for developing sound nitrogen management policies. We used a spatially referenced regression analysis (SPARROW) to examine landscape characteristics influencing delivery of nitrogen from sources in a watershed to stream channels. Modelled landscape delivery ratio varies widely (by a factor of 4) among watersheds in the southeastern United States—higher in the western part (Tennessee, Alabama, and Mississippi) than in the eastern part, and the average value for the region is lower compared to other parts of the nation. When we model landscape delivery ratio as a continuous function of local-scale landscape characteristics, we estimate a spatial pattern that varies as a function of soil and climate characteristics but exhibits spatial structure in residuals (observed load minus predicted load). The spatial pattern of modelled landscape delivery ratio and the spatial pattern of residuals coincide spatially with Level III ecoregions and also with hydrologic landscape regions. Subsequent incorporation into the model of these frameworks as regional scale variables improves estimation of landscape delivery ratio, evidenced by reduced spatial bias in residuals, and suggests that cross-scale processes affect nitrogen attenuation on the landscape. The model-fitted coefficient values are logically consistent with the hypothesis that broad-scale classifications of hydrologic response help to explain differential rates of nitrogen attenuation, controlling for local-scale landscape characteristics. Negative model coefficients for hydrologic landscape regions where the primary flow path is shallow ground water suggest that a lower fraction of nitrogen mass will be delivered to streams; this relation is reversed for regions where the primary flow path is overland flow.

An observer study comparing spot imaging regions selected by radiologists and a computer for an automated stereo spot mammography technique

International Nuclear Information System (INIS)

Goodsitt, Mitchell M.; Chan, Heang-Ping; Lydick, Justin T.; Gandra, Chaitanya R.; Chen, Nelson G.; Helvie, Mark A.; Bailey, Janet E.; Roubidoux, Marilyn A.; Paramagul, Chintana; Blane, Caroline E.; Sahiner, Berkman; Petrick, Nicholas A.

2004-01-01

We are developing an automated stereo spot mammography technique for improved imaging of suspicious dense regions within digital mammograms. The technique entails the acquisition of a full-field digital mammogram, automated detection of a suspicious dense region within that mammogram by a computer aided detection (CAD) program, and acquisition of a stereo pair of images with automated collimation to the suspicious region. The latter stereo spot image is obtained within seconds of the original full-field mammogram, without releasing the compression paddle. The spot image is viewed on a stereo video display. A critical element of this technique is the automated detection of suspicious regions for spot imaging. We performed an observer study to compare the suspicious regions selected by radiologists with those selected by a CAD program developed at the University of Michigan. True regions of interest (TROIs) were separately determined by one of the radiologists who reviewed the original mammograms, biopsy images, and histology results. We compared the radiologist and computer-selected regions of interest (ROIs) to the TROIs. Both the radiologists and the computer were allowed to select up to 3 regions in each of 200 images (mixture of 100 CC and 100 MLO views). We computed overlap indices (the overlap index is defined as the ratio of the area of intersection to the area of interest) to quantify the agreement between the selected regions in each image. The averages of the largest overlap indices per image for the 5 radiologist-to-computer comparisons were directly related to the average number of regions per image traced by the radiologists (about 50% for 1 region/image, 84% for 2 regions/image and 96% for 3 regions/image). The average of the overlap indices with all of the TROIs was 73% for CAD and 76.8%+/-10.0% for the radiologists. This study indicates that the CAD determined ROIs could potentially be useful for a screening technique that includes stereo spot

Classifying Dementia Using Local Binary Patterns from Different Regions in Magnetic Resonance Images

Directory of Open Access Journals (Sweden)

Ketil Oppedal

2015-01-01

Full Text Available Dementia is an evolving challenge in society, and no disease-modifying treatment exists. Diagnosis can be demanding and MR imaging may aid as a noninvasive method to increase prediction accuracy. We explored the use of 2D local binary pattern (LBP extracted from FLAIR and T1 MR images of the brain combined with a Random Forest classifier in an attempt to discern patients with Alzheimer's disease (AD, Lewy body dementia (LBD, and normal controls (NC. Analysis was conducted in areas with white matter lesions (WML and all of white matter (WM. Results from 10-fold nested cross validation are reported as mean accuracy, precision, and recall with standard deviation in brackets. The best result we achieved was in the two-class problem NC versus AD + LBD with total accuracy of 0.98 (0.04. In the three-class problem AD versus LBD versus NC and the two-class problem AD versus LBD, we achieved 0.87 (0.08 and 0.74 (0.16, respectively. The performance using 3DT1 images was notably better than when using FLAIR images. The results from the WM region gave similar results as in the WML region. Our study demonstrates that LBP texture analysis in brain MR images can be successfully used for computer based dementia diagnosis.

The first X-ray imaging spectroscopy of quiescent solar active regions with NuSTAR

DEFF Research Database (Denmark)

Hannah, Iain G.; Grefenstette, Brian W.; Smith, David M.

2016-01-01

We present the first observations of quiescent active regions (ARs) using the Nuclear Spectroscopic Telescope Array (NuSTAR), a focusing hard X-ray telescope capable of studying faint solar emission from high-temperature and non-thermal sources. We analyze the first directly imaged and spectrally...... resolved X-rays above 2 keV from non-flaring ARs, observed near the west limb on 2014 November 1. The NuSTAR X-ray images match bright features seen in extreme ultraviolet and soft X-rays. The NuSTAR imaging spectroscopy is consistent with isothermal emission of temperatures 3.1-4.4 MK and emission...

The importance of theory of regional culture in city image shaping

Institute of Scientific and Technical Information of China (English)

吴婷

2015-01-01

In this paper:Regional culture in a certain region within the scope and the integration of the environment, as a regional brand, unique. The development of regional culture and heritage have important influence on city image.

Me, myself, and Ikea : Qualifying generic self-referencing effects in brand judgment

NARCIS (Netherlands)

Fennis, Bob M.; Wiebenga, Jacob H.

The present research extends previous work on the latent tendency to be attracted to objects, events and entities that are associated with the self by demonstrating when and how generic self-referencing brand names influence brand judgment. In five studies we hypothesize and find that using pronouns

Comparison of benzodiazepine receptor and regional cerebral blood flow imagings of epileptiform foci in hippocampal kindled rabbits

International Nuclear Information System (INIS)

Kurokawa, Kenzo

1993-01-01

To compare the benzodiazepine (Bz) receptor imaging and regional cerebral blood flow (rCBF) imaging in the detection of epileptic foci, the distribution pattern of the Bz receptor and rCBF in hippocampal kindled rabbits was examined by a double tracer autoradiography using ethyl 7-[ 125 I]-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1, 5-a][1,4] benzodiazepine-3-carboxylate ( 125 I-Ro 16-0154) and 99m Tc-hexamethyl-propyleneamine oxime ( 99m Tc-HMPAO). In visual and quantitative analyses, 125 I-Ro 16-0154 accumulation in brain slices extracted after the completion of the kindling was markedly and extensively decreased in the kindled CA1 region mimicking a primary epileptic focus. 125 I-Ro 16-0154 accumulation was moderately decreased in the ipsilateral temporal lobe, dentate gyrus, CA2, CA4, and bilateral CA3 regions, regarded as the propagated sites of seizure discharges. 99m Tc-HMPAO accumulation was found to be decreased in the ipsilateral CA1, frontal, temporal and dentate gyri. However, the decrease was much more slight and less extensive than that in 125 I-Ro 16-0154 accumulation. These results suggest that Bz receptor imaging is much more sensitive in the detection of epileptic foci than rCBF imaging, and therefore that Bz receptor imaging is useful in clinical epilepsy. (author)

Cool transition region loops observed by the Interface Region Imaging Spectrograph

Science.gov (United States)

Huang, Z.; Xia, L.; Li, B.; Madjarska, M. S.

2015-12-01

An important class of loops in the solar atmosphere, cool transition region loops, have received little attention mainly due to instrumental limitations. We analyze a cluster of these loops in the on-disk active region NOAA 11934 recorded in a Si IV 1402.8 Å spectral raster and 1400Å slit-jaw (SJ) images taken by the Interface Region Imaging Spectrograph. We divide these loops into three groups and study their dynamics, evolution and interaction.The first group comprises geometrically relatively stable loops, which are finely scaled with 382~626 km cross-sections. Siphon flows in these loops are suggested by the Doppler velocities gradually changing from -10 km/s (blue-shifts) in one end to 20 km/s (red-shifts) in the other. Nonthermal velocities from 15 to 25 km/s were determined. The obtained physical properties suggest that these loops are impulsively heated by magnetic reconnection occurring at the blue-shifted footpoints where magnetic cancellation with a rate of 1015 Mx/s is found. The released magnetic energy is redistributed by the siphon flows. The second group corresponds to two active footpoints rooted in mixed-magnetic-polarity regions. Magnetic reconnection in both footpoints is suggested by explosive-event line profiles with enhanced wings up to 200 km/s and magnetic cancellation with a rate of ~1015 Mx/s. In the third group, an interaction between two cool loop systems is observed. Mixed-magnetic polarities are seen in their conjunction area where explosive-event line profiles and magnetic cancellation with a rate of 3×1015 Mx/s are found. This is a clear indication that magnetic reconnection occurs between these two loop systems. Our observations suggest that the cool transition region loops are heated impulsively most likely by sequences of magnetic reconnection events.

Assessment of image display of contrast enhanced T1W images with fat suppression

International Nuclear Information System (INIS)

Miyazaki, Isao; Ishizaki, Keiko; Kobayashi, Kuninori; Katou, Masanobu

2006-01-01

The effects of imaging conditions and measures for their improvement were examined with regard to recognition of the effects of contrast on images when T 1 -weighted imaging with selective fat suppression was applied. Luminance at the target region was examined before and after contrast imaging using phantoms assuming pre- and post-imaging conditions. A clinical examination was performed on tumors revealed by breast examination, including those surrounded by mammary gland and by fat tissue. When fat suppression was used and imaging contrast was enhanced, the luminance level of fat tumors with the same structure as the prepared phantoms appeared to be high both before and after contrast imaging, and the effects of contrast were not distinguishable. This observation is attributable to the fact that the imaging conditions before and after contrast imaging were substantially different. To make a comparison between pre- and post-contrast images, it is considered necessary to perform imaging with fixed receiver gain and to apply the same imaging method for pre- and post-contrast images by adjusting post-contrast imaging conditions to those of pre-contrast imaging. (author)

Combining MOD10A1 and MYD10A1 Images For Snow Cover Area Monitoring

Science.gov (United States)

Tekeli, A. E.

2008-12-01

MOD10A1 and MYD10A1 daily snow cover maps at 500 m resolution are available from MODIS sensors on Terra and Aqua satellites. Aqua obtains the image of same region approximately three hours after Terra over Turkey region. MODIS is an optic sensor and cloud cover degrades the usability of derived snow cover maps. Moreover, spectral similarity between clouds and snow complicates their separability in visible imagery. Fortunately, dynamic behavior of clouds enables their discrimination from snow stationary on the surface. Combined use of MOD10A1 and MYD10A1 images mostly reduces the cloud cover present in one image alone and provides better representation of surface snow cover. Comparison of merged images with in situ data indicated higher hit ratios. The individual comparison of MOD10A1 and MYD10A1 images with ground data each yielded 31% hit ratio whereas, the merged images provided 38%. One-day shifts in comparisons increased hit ratios to 52 % and 46% whereas and two-day shifts gave 77 % and 79 % for MOD10A1 and MYD10A1 respectively. Merged maps yielded 54% and 83% for one and two day shifts. The improvement provided by the merging technique is found to be 7% for the present day, 7 % for one- day and 5% for two-day shifts for the whole season. Monthly decomposition resulted 25% improvement as the maximum. The snow cover product obtained by merging Terra and Aqua satellites provided higher hit ratios, as expected.

A NEW APPROACH TO FAST MOSAIC UAV IMAGES

Directory of Open Access Journals (Sweden)

Q. Liu

2012-09-01

Full Text Available Unmanned Aerial Vehicles (UAVs have been widely used to acquire high quality terrain images of the areas of interest, particularly when such a task could potentially risk human life or even impossible as the areas cannot be accessed easily by surveyors. Once the images have been obtained, traditional photogrammetric processing process can be used to establish a relative orientation model and then, absolute orientation model with the procedures of space resection and intersection. In many such applications, the geo- referenced images which are stitched together to represent the geospatial relationships for the feature objects are sufficient. A fast or near real-time processing approach for UAV images using GPS/INS data has being investigated for years. One beneficial application of such approach is the capability of quick production of geo-referenced images for various engineering or business activities, such as urban and road planning, the site selection of factories and bridges, etc. In this paper, we have proposed a new fast processing approach for the UAV images collected with an integrated GPS/INS/Vision system. The approach features that the corresponding points between images have been determined, and then coordinate transformation is carried out to implement image stitching. The accuracy of corresponding points normally affects the quality of stitched images, but the results of our experiments revealed that the image stitching errors were obvious even the accuracy of corresponding points was high. The stitching errors could be caused by the changes of surface elevation.

Digital image monitoring to optimise safe port operation

CSIR Research Space (South Africa)

Phelp, D

2008-11-01

Full Text Available This paper describes a low cost video system ‘Harbour Watch’, which can be used to support safe port operations, especially in developing countries. Preset digital images are geo-referenced and then archived for later analysis to improve...

Tracking Regional Tissue Volume and Function Change in Lung Using Image Registration

Directory of Open Access Journals (Sweden)

Kunlin Cao

2012-01-01

Full Text Available We have previously demonstrated the 24-hour redistribution and reabsorption of bronchoalveolar lavage (BAL fluid delivered to the lung during a bronchoscopic procedure in normal volunteers. In this work we utilize image-matching procedures to correlate fluid redistribution and reabsorption to changes in regional lung function. Lung CT datasets from six human subjects were used in this study. Each subject was scanned at four time points before and after BAL procedure. Image registration was performed to align images at different time points and different inflation levels. The resulting dense displacement fields were utilized to track tissue volume changes and reveal deformation patterns of local parenchymal tissue quantitatively. The registration accuracy was assessed by measuring landmark matching errors, which were on the order of 1 mm. The results show that quantitative-assessed fluid volume agreed well with bronchoscopist-reported unretrieved BAL volume in the whole lungs (squared linear correlation coefficient was 0.81. The average difference of lung tissue volume at baseline and after 24 hours was around 2%, which indicates that BAL fluid in the lungs was almost absorbed after 24 hours. Regional lung-function changes correlated with the presence of BAL fluid, and regional function returned to baseline as the fluid was reabsorbed.

Pathfinder: multiresolution region-based searching of pathology images using IRM.

OpenAIRE

Wang, J. Z.

2000-01-01

The fast growth of digitized pathology slides has created great challenges in research on image database retrieval. The prevalent retrieval technique involves human-supplied text annotations to describe slide contents. These pathology images typically have very high resolution, making it difficult to search based on image content. In this paper, we present Pathfinder, an efficient multiresolution region-based searching system for high-resolution pathology image libraries. The system uses wave...

PROTOPLANETARY DISKS IN THE ORION OMC1 REGION IMAGED WITH ALMA

Energy Technology Data Exchange (ETDEWEB)

Eisner, J. A.; Sheehan, P. D. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Bally, J. M. [Department of Astrophysical and Planetary Sciences, University of Colorado, UCB 389, Boulder, CO 80309 (United States); Ginsburg, A., E-mail: jeisner@email.arizona.edu [ESO Headquarters, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Munchen (Germany)

2016-07-20

We present ALMA observations of the Orion Nebula that cover the OMC1 outflow region. Our focus in this paper is on compact emission from protoplanetary disks. We mosaicked a field containing ∼600 near-IR-identified young stars, around which we can search for sub-millimeter emission tracing dusty disks. Approximately 100 sources are known proplyds identified with the Hubble Space Telescope . We detect continuum emission at 1 mm wavelengths toward ∼20% of the proplyd sample, and ∼8% of the larger sample of near-IR objects. The noise in our maps allows 4 σ detection of objects brighter than ∼1.5 mJy, corresponding to protoplanetary disk masses larger than 1.5 M {sub J} (using standard assumptions about dust opacities and gas-to-dust ratios). None of these disks are detected in contemporaneous CO(2-1) or C{sup 18}O(2-1) observations, suggesting that the gas-to-dust ratios may be substantially smaller than the canonical value of 100. Furthermore, since dust grains may already be sequestered in large bodies in Orion Nebula cluster (ONC) disks, the inferred masses of disk solids may be underestimated. Our results suggest that the distribution of disk masses in this region is compatible with the detection rate of massive planets around M dwarfs, which are the dominant stellar constituent in the ONC.

Interpreting the Right to an Education as a Norm Referenced Adequacy Standard

Science.gov (United States)

Pijanowski, John

2016-01-01

Our current conceptions of educational adequacy emerged out of an era dominated by equity-based school resource litigation. During that time of transitioning between successful litigation strategies, legal opinions provided clues as to how future courts might view a norm-referenced approach to establishing an adequacy standard--an approach that…

Development and Implementation of Domain Referenced Testing in Vocational Welding. Final Report.

Science.gov (United States)

Sterrett, Dan

A project was undertaken to develop and implement domain-referenced tests (DRTs) for welders' helpers. After analyzing the results of a state survey of welding job titles and related tasks and after consulting with postsecondary educators and industry personnel, researchers developed DRTs to measure various tasks typically performed by welders.…

Ministry of Health and regional health agency measures for medical imaging

International Nuclear Information System (INIS)

Podeur, Annie

2011-01-01

The issues in imaging are the appropriate use of equipment and optimising the organisation of imaging facilities, through a pooling of medical resources. The Ministry responsible for health has confirmed its desire to increase the number of MRI devices in order to better address patient needs in compliance with best practices, especially in dealing with strokes and cancers. The primary need is to reinforce radiation protection, essentially with regard to children. The steps taken are designed to speed up the replacement of irradiating techniques. According to the SROS-PRS (regional health care organisation scheme - regional health care project), the ARS (regional health agencies) are required to mobilize all resources in order to meet the national objectives for improving access to imaging and reducing disparities in access and efficiency. It is up to the ARS to define the territorial distribution of supply, with appropriate gradation of imaging facilities, in particular to ensure a permanent supply of care. (author)

Automated detection of regions of interest for tissue microarray experiments: an image texture analysis

International Nuclear Information System (INIS)

Karaçali, Bilge; Tözeren, Aydin

2007-01-01

Recent research with tissue microarrays led to a rapid progress toward quantifying the expressions of large sets of biomarkers in normal and diseased tissue. However, standard procedures for sampling tissue for molecular profiling have not yet been established. This study presents a high throughput analysis of texture heterogeneity on breast tissue images for the purpose of identifying regions of interest in the tissue for molecular profiling via tissue microarray technology. Image texture of breast histology slides was described in terms of three parameters: the percentage of area occupied in an image block by chromatin (B), percentage occupied by stroma-like regions (P), and a statistical heterogeneity index H commonly used in image analysis. Texture parameters were defined and computed for each of the thousands of image blocks in our dataset using both the gray scale and color segmentation. The image blocks were then classified into three categories using the texture feature parameters in a novel statistical learning algorithm. These categories are as follows: image blocks specific to normal breast tissue, blocks specific to cancerous tissue, and those image blocks that are non-specific to normal and disease states. Gray scale and color segmentation techniques led to identification of same regions in histology slides as cancer-specific. Moreover the image blocks identified as cancer-specific belonged to those cell crowded regions in whole section image slides that were marked by two pathologists as regions of interest for further histological studies. These results indicate the high efficiency of our automated method for identifying pathologic regions of interest on histology slides. Automation of critical region identification will help minimize the inter-rater variability among different raters (pathologists) as hundreds of tumors that are used to develop an array have typically been evaluated (graded) by different pathologists. The region of interest

Mid-infrared thermal imaging for an effective mapping of surface materials and sub-surface detachments in mural paintings: integration of thermography and thermal quasi-reflectography

Science.gov (United States)

Daffara, C.; Parisotto, S.; Mariotti, P. I.

2015-06-01

Cultural Heritage is discovering how precious is thermal analysis as a tool to improve the restoration, thanks to its ability to inspect hidden details. In this work a novel dual mode imaging approach, based on the integration of thermography and thermal quasi-reflectography (TQR) in the mid-IR is demonstrated for an effective mapping of surface materials and of sub-surface detachments in mural painting. The tool was validated through a unique application: the "Monocromo" by Leonardo da Vinci in Italy. The dual mode acquisition provided two spatially aligned dataset: the TQR image and the thermal sequence. Main steps of the workflow included: 1) TQR analysis to map surface features and 2) to estimate the emissivity; 3) projection of the TQR frame on reference orthophoto and TQR mosaicking; 4) thermography analysis to map detachments; 5) use TQR to solve spatial referencing and mosaicking for the thermal-processed frames. Referencing of thermal images in the visible is a difficult aspect of the thermography technique that the dual mode approach allows to solve in effective way. We finally obtained the TQR and the thermal maps spatially referenced to the mural painting, thus providing the restorer a valuable tool for the restoration of the detachments.

Wind Statistics Offshore based on Satellite Images

DEFF Research Database (Denmark)

Hasager, Charlotte Bay; Mouche, Alexis; Badger, Merete

2009-01-01

-based observations become available. At present preliminary results are obtained using the routine methods. The first step in the process is to retrieve raw SAR data, calibrate the images and use a priori wind direction as input to the geophysical model function. From this process the wind speed maps are produced....... The wind maps are geo-referenced. The second process is the analysis of a series of geo-referenced SAR-based wind maps. Previous research has shown that a relatively large number of images are needed for achieving certain accuracies on mean wind speed, Weibull A and k (scale and shape parameters......Ocean wind maps from satellites are routinely processed both at Risø DTU and CLS based on the European Space Agency Envisat ASAR data. At Risø the a priori wind direction is taken from the atmospheric model NOGAPS (Navel Operational Global Atmospheric Prediction System) provided by the U.S. Navy...

Cortical region of interest definition on SPECT brain images using X-ray CT registration

Energy Technology Data Exchange (ETDEWEB)

Tzourio, N.; Sutton, D. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot); Joliot, M. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot INSERM, Orsay (France)); Mazoyer, B.M. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot Antenne d' Information Medicale, C.H.U. Bichat, Paris (France)); Charlot, V. (Hopital Louis Mourier, Colombes (France). Service de Psychiatrie); Salamon, G. (CHU La Timone, Marseille (France). Service de Neuroradiologie)

1992-11-01

We present a method for brain single photon emission computed tomography (SPECT) analysis based on individual registration of anatomical (CT) and functional ([sup 133]Xe regional cerebral blood flow) images and on the definition of three-dimensional functional regions of interest. Registration of CT and SPECT is performed through adjustment of CT-defined cortex limits to the SPECT image. Regions are defined by sectioning a cortical ribbon on the CT images, copied over the SPECT images and pooled through slices to give 3D cortical regions of interest. The proposed method shows good intra- and interobserver reproducibility (regional intraclass correlation coefficient [approx equal]0.98), and good accuracy in terms of repositioning ([approx equal]3.5 mm) as compared to the SPECT image resolution (14 mm). The method should be particularly useful for analysing SPECT studies when variations in brain anatomy (normal or abnormal) must be accounted for. (orig.).

25 CFR 1000.276 - Does FTCA apply to a self-governance AFA if FTCA is not referenced in the AFA?

Science.gov (United States)

2010-04-01

...-governance AFA if FTCA is not referenced in the AFA? Yes, FTCA applies even if the AFA does not mention it. ... 25 Indians 2 2010-04-01 2010-04-01 false Does FTCA apply to a self-governance AFA if FTCA is not referenced in the AFA? 1000.276 Section 1000.276 Indians OFFICE OF THE ASSISTANT SECRETARY, INDIAN AFFAIRS...

Utility of an airframe referenced spatial auditory display for general aviation operations

Science.gov (United States)

Naqvi, M. Hassan; Wigdahl, Alan J.; Ranaudo, Richard J.

2009-05-01

The University of Tennessee Space Institute (UTSI) completed flight testing with an airframe-referenced localized audio cueing display. The purpose was to assess its affect on pilot performance, workload, and situational awareness in two scenarios simulating single-pilot general aviation operations under instrument meteorological conditions. Each scenario consisted of 12 test procedures conducted under simulated instrument meteorological conditions, half with the cue off, and half with the cue on. Simulated aircraft malfunctions were strategically inserted at critical times during each test procedure. Ten pilots participated in the study; half flew a moderate workload scenario consisting of point to point navigation and holding pattern operations and half flew a high workload scenario consisting of non precision approaches and missed approach procedures. Flight data consisted of aircraft and navigation state parameters, NASA Task Load Index (TLX) assessments, and post-flight questionnaires. With localized cues there was slightly better pilot technical performance, a reduction in workload, and a perceived improvement in situational awareness. Results indicate that an airframe-referenced auditory display has utility and pilot acceptance in general aviation operations.

Comparison of manual and semi-automated delineation of regions of interest for radioligand PET imaging analysis

International Nuclear Information System (INIS)

Chow, Tiffany W; Verhoeff, Nicolaas PLG; Takeshita, Shinichiro; Honjo, Kie; Pataky, Christina E; St Jacques, Peggy L; Kusano, Maggie L; Caldwell, Curtis B; Ramirez, Joel; Black, Sandra

2007-01-01

As imaging centers produce higher resolution research scans, the number of man-hours required to process regional data has become a major concern. Comparison of automated vs. manual methodology has not been reported for functional imaging. We explored validation of using automation to delineate regions of interest on positron emission tomography (PET) scans. The purpose of this study was to ascertain improvements in image processing time and reproducibility of a semi-automated brain region extraction (SABRE) method over manual delineation of regions of interest (ROIs). We compared 2 sets of partial volume corrected serotonin 1a receptor binding potentials (BPs) resulting from manual vs. semi-automated methods. BPs were obtained from subjects meeting consensus criteria for frontotemporal degeneration and from age- and gender-matched healthy controls. Two trained raters provided each set of data to conduct comparisons of inter-rater mean image processing time, rank order of BPs for 9 PET scans, intra- and inter-rater intraclass correlation coefficients (ICC), repeatability coefficients (RC), percentages of the average parameter value (RM%), and effect sizes of either method. SABRE saved approximately 3 hours of processing time per PET subject over manual delineation (p < .001). Quality of the SABRE BP results was preserved relative to the rank order of subjects by manual methods. Intra- and inter-rater ICC were high (>0.8) for both methods. RC and RM% were lower for the manual method across all ROIs, indicating less intra-rater variance across PET subjects' BPs. SABRE demonstrated significant time savings and no significant difference in reproducibility over manual methods, justifying the use of SABRE in serotonin 1a receptor radioligand PET imaging analysis. This implies that semi-automated ROI delineation is a valid methodology for future PET imaging analysis

Impact of region contouring variability on image-based focal therapy evaluation

Science.gov (United States)

Gibson, Eli; Donaldson, Ian A.; Shah, Taimur T.; Hu, Yipeng; Ahmed, Hashim U.; Barratt, Dean C.

2016-03-01

Motivation: Focal therapy is an emerging low-morbidity treatment option for low-intermediate risk prostate cancer; however, challenges remain in accurately delivering treatment to specified targets and determining treatment success. Registered multi-parametric magnetic resonance imaging (MPMRI) acquired before and after treatment can support focal therapy evaluation and optimization; however, contouring variability, when defining the prostate, the clinical target volume (CTV) and the ablation region in images, reduces the precision of quantitative image-based focal therapy evaluation metrics. To inform the interpretation and clarify the limitations of such metrics, we investigated inter-observer contouring variability and its impact on four metrics. Methods: Pre-therapy and 2-week-post-therapy standard-of-care MPMRI were acquired from 5 focal cryotherapy patients. Two clinicians independently contoured, on each slice, the prostate (pre- and post-treatment) and the dominant index lesion CTV (pre-treatment) in the T2-weighted MRI, and the ablated region (post-treatment) in the dynamic-contrast- enhanced MRI. For each combination of clinician contours, post-treatment images were registered to pre-treatment images using a 3D biomechanical-model-based registration of prostate surfaces, and four metrics were computed: the proportion of the target tissue region that was ablated and the target:ablated region volume ratio for each of two targets (the CTV and an expanded planning target volume). Variance components analysis was used to measure the contribution of each type of contour to the variance in the therapy evaluation metrics. Conclusions: 14-23% of evaluation metric variance was attributable to contouring variability (including 6-12% from ablation region contouring); reducing this variability could improve the precision of focal therapy evaluation metrics.

Light-leaking region segmentation of FOG fiber based on quality evaluation of infrared image

Science.gov (United States)

Liu, Haoting; Wang, Wei; Gao, Feng; Shan, Lianjie; Ma, Yuzhou; Ge, Wenqian

2014-07-01

To improve the assembly reliability of Fiber Optic Gyroscope (FOG), a light leakage detection system and method is developed. First, an agile movement control platform is designed to implement the pose control of FOG optical path component in 6 Degrees of Freedom (DOF). Second, an infrared camera is employed to capture the working state images of corresponding fibers in optical path component after the manual assembly of FOG; therefore the entire light transmission process of key sections in light-path can be recorded. Third, an image quality evaluation based region segmentation method is developed for the light leakage images. In contrast to the traditional methods, the image quality metrics, including the region contrast, the edge blur, and the image noise level, are firstly considered to distinguish the image characters of infrared image; then the robust segmentation algorithms, including graph cut and flood fill, are all developed for region segmentation according to the specific image quality. Finally, after the image segmentation of light leakage region, the typical light-leaking type, such as the point defect, the wedge defect, and the surface defect can be identified. By using the image quality based method, the applicability of our proposed system can be improved dramatically. Many experiment results have proved the validity and effectiveness of this method.

Using Norm-Referenced Tests to Determine Severity of Language Impairment in Children: Disconnect between U.S. Policy Makers and Test Developers

Science.gov (United States)

Spaulding, Tammie J.; Szulga, Margaret Swartwout; Figueroa, Cecilia

2012-01-01

Purpose: The purpose of this study was to identify various U.S. state education departments' criteria for determining the severity of language impairment in children, with particular focus on the use of norm-referenced tests. A secondary objective was to determine if norm-referenced tests of child language were developed for the purpose of…

Medical Image Fusion Algorithm Based on Nonlinear Approximation of Contourlet Transform and Regional Features

Directory of Open Access Journals (Sweden)

Hui Huang

2017-01-01

Full Text Available According to the pros and cons of contourlet transform and multimodality medical imaging, here we propose a novel image fusion algorithm that combines nonlinear approximation of contourlet transform with image regional features. The most important coefficient bands of the contourlet sparse matrix are retained by nonlinear approximation. Low-frequency and high-frequency regional features are also elaborated to fuse medical images. The results strongly suggested that the proposed algorithm could improve the visual effects of medical image fusion and image quality, image denoising, and enhancement.

Fluorescence-enhanced optical imaging in large tissue volumes using a gain-modulated ICCD camera

International Nuclear Information System (INIS)

Godavarty, Anuradha; Eppstein, Margaret J; Zhang, Chaoyang; Theru, Sangeeta; Thompson, Alan B; Gurfinkel, Michael; Sevick-Muraca, Eva M

2003-01-01

A novel image-intensified charge-coupled device (ICCD) imaging system has been developed to perform 3D fluorescence tomographic imaging in the frequency-domain using near-infrared contrast agents. The imager is unique since it (i) employs a large tissue-mimicking phantom, which is shaped and sized to resemble a female breast and part of the extended chest-wall region, and (ii) enables rapid data acquisition in the frequency-domain by using a gain-modulated ICCD camera. Diffusion model predictions are compared to experimental measurements using two different referencing schemes under two different experimental conditions of perfect and imperfect uptake of fluorescent agent into a target. From these experimental measurements, three-dimensional images of fluorescent absorption were reconstructed using a computationally efficient variant of the approximate extended Kalman filter algorithm. The current work represents the first time that 3D fluorescence-enhanced optical tomographic reconstructions have been achieved from experimental measurements of the time-dependent light propagation on a clinically relevant breast-shaped tissue phantom using a gain-modulated ICCD camera

Creating an image of a region – Euroregion Beskydy and Euroregion Cieszyn Silesia examples

Directory of Open Access Journals (Sweden)

Wróblewski Łukasz

2016-03-01

Full Text Available In the discussion of communication in management studies, more and more attention is being given to research on an image of a product as well as a brand of an institution. In times when the value of great corporations is mainly based on well promoted and maintained brands, any activity without care of reputation is unimaginable. This rule also applies to cities, communes or regions. Image is currently of strategic significance for these subjects. It can be stated that there is a type of relationship. When an image of a certain region is positive, achievement of complex goals is easier. Therefore, when the region fulfils its goals, it is easier to gain respect of current and potential citizens, tourists, and investors. Thus, a positive image is one of the greatest advantages that a region can have, as it is directly transferred into social and economic development. In the article, on the basis of the literature of the subject, the process of creating an image of a region is presented.According to the survey conducted among Polish and Czech respondents related to Euroregion Beskydy and Euroregion Cieszyn Silesia, by place of residence, workplace or place of education image of the regions appeared to be one of the most distinguishing of their features.

Characterization of cervigram image sharpness using multiple self-referenced measurements and random forest classifiers

Science.gov (United States)

Jaiswal, Mayoore; Horning, Matt; Hu, Liming; Ben-Or, Yau; Champlin, Cary; Wilson, Benjamin; Levitz, David

2018-02-01

Cervical cancer is the fourth most common cancer among women worldwide and is especially prevalent in low resource settings due to lack of screening and treatment options. Visual inspection with acetic acid (VIA) is a widespread and cost-effective screening method for cervical pre-cancer lesions, but accuracy depends on the experience level of the health worker. Digital cervicography, capturing images of the cervix, enables review by an off-site expert or potentially a machine learning algorithm. These reviews require images of sufficient quality. However, image quality varies greatly across users. A novel algorithm was developed to evaluate the sharpness of images captured with the MobileODT's digital cervicography device (EVA System), in order to, eventually provide feedback to the health worker. The key challenges are that the algorithm evaluates only a single image of each cervix, it needs to be robust to the variability in cervix images and fast enough to run in real time on a mobile device, and the machine learning model needs to be small enough to fit on a mobile device's memory, train on a small imbalanced dataset and run in real-time. In this paper, the focus scores of a preprocessed image and a Gaussian-blurred version of the image are calculated using established methods and used as features. A feature selection metric is proposed to select the top features which were then used in a random forest classifier to produce the final focus score. The resulting model, based on nine calculated focus scores, achieved significantly better accuracy than any single focus measure when tested on a holdout set of images. The area under the receiver operating characteristics curve was 0.9459.

MRI image characteristics of materials implanted at sellar region after transsphenoidal resection of pituitary tumours

International Nuclear Information System (INIS)

Bladowska, J.; Sasiadek, M.; Bednarek-Tupikowska, G.; Sokolska, V.; Badowski, R.; Moron, K.; Bonicki, W.

2010-01-01

Background: Post-surgical evaluation of the pituitary gland in MRI is difficult because of a change in anatomical conditions. It depends also on numerous other factors, including: size and expansion of the tumour before surgery, type of surgical access, quality and volume of implanted materials and time of its resorption. The purpose was to demonstrate the characteristics of the implanted materials on MRI performed after transsphenoidal resection of pituitary tumours and to identify imaging criteria helpful in differential diagnosis of masses within the sellar region. Material/Methods: One hundred and fifty-four patients after transsphenoidal resection of pituitary tumours were included in the study. In general, 469 MRI examinations were performed with a 1.5 T scanner. We obtained T1-weighted sagittal and coronal, enhanced and unenhanced images. In 102 cases, additional T2-weighted coronal, unenhanced images with 1.5 T unit were obtained as well. Results: The implanted materials appeared in 95 patient: fat in 86 and muscle with fascia in 3 patients. We could recognise implanted muscle and fascia in T2-weighted images, because of high signal intensity of the degenerating muscle and the line of low signal representing fascia. The implanted titanium mesh was found in 4 patients. Haemostatic materials were visible only in 2 patients in examinations performed at an early postoperative stage (1 month after the procedure). Conclusions: The knowledge of MRI characteristics of the materials implanted at the sellar region is very important in postoperative diagnosis of pituitary tumours and may help discriminate between tumorous and non-tumorous involvement of the sellar region. Some implanted materials, like fat, could be seen on MRI for as long as 10 years after the operation, others, like haemostatic materials, for only 1 month after surgery. T2-weighted imaging is a useful assessment method of the implanted muscle and fascia for a long time after surgery. (authors)

A statistically robust EEG re-referencing procedure to mitigate reference effect

OpenAIRE

Lepage, Kyle Q.; Kramer, Mark A.; Chu, Catherine J.

2014-01-01

Background: The electroencephalogram (EEG) remains the primary tool for diagnosis of abnormal brain activity in clinical neurology and for in vivo recordings of human neurophysiology in neuroscience research. In EEG data acquisition, voltage is measured at positions on the scalp with respect to a reference electrode. When this reference electrode responds to electrical activity or artifact all electrodes are affected. Successful analysis of EEG data often involves re-referencing procedures th...

An effective detection algorithm for region duplication forgery in digital images

Science.gov (United States)

Yavuz, Fatih; Bal, Abdullah; Cukur, Huseyin

2016-04-01

Powerful image editing tools are very common and easy to use these days. This situation may cause some forgeries by adding or removing some information on the digital images. In order to detect these types of forgeries such as region duplication, we present an effective algorithm based on fixed-size block computation and discrete wavelet transform (DWT). In this approach, the original image is divided into fixed-size blocks, and then wavelet transform is applied for dimension reduction. Each block is processed by Fourier Transform and represented by circle regions. Four features are extracted from each block. Finally, the feature vectors are lexicographically sorted, and duplicated image blocks are detected according to comparison metric results. The experimental results show that the proposed algorithm presents computational efficiency due to fixed-size circle block architecture.

A Psychometric Review of Norm-Referenced Tests Used to Assess Phonological Error Patterns

Science.gov (United States)

Kirk, Celia; Vigeland, Laura

2014-01-01

Purpose: The authors provide a review of the psychometric properties of 6 norm-referenced tests designed to measure children's phonological error patterns. Three aspects of the tests' psychometric adequacy were evaluated: the normative sample, reliability, and validity. Method: The specific criteria used for determining the psychometric…

Repeatability of regional myocardial blood flow calculation in 82Rb PET imaging

International Nuclear Information System (INIS)

Knešaurek, Karin; Machac, Josef; Zhang, Zhuangyu

2009-01-01

We evaluated the repeatability of the calculation of myocardial blood flow (MBF) at rest and pharmacological stress, and calculated the coronary flow reserve (CFR) utilizing 82 Rb PET imaging. The aim of the research was to prove high repeatability for global MBF and CFR values and good repeatability for regional MBF and CFR values. The results will have significant impact on cardiac PET imaging in terms of making it more affordable and increasing its use. 12 normal volunteers were imaged at rest and during pharmacological stress, with 2220 MBq of 82 Rb each. A GE Advance PET system was used to acquire dynamic 50-frame studies. MBF was calculated with a 2-compartmental model using a modified PMOD program (PMOD; University Hospital Zurich, Zurich, Switzerland). Two differential equations, describing a 2-compartmental model, were solved by numerical integration and using Levenberg-Marquardt's method for fitting data. The PMOD program defines 16 standard segments and calculates myocardial flow for each segment, as well as average septal, anterior, lateral, inferior and global flow. Repeatability was evaluated according to the method of Bland and Altman. Global rest and stress MBF, as well as global CFR, showed very good repeatability. No significant differences were found between the paired resting global MBF (0.63 ± 0.13 vs. 0.64 ± 0.13 mL/min/g; mean difference, -1.0% ± 2.6%) and the stress global MBF (1.37 ± 0.23 vs. 1.37 ± 0.24; mean difference, 0.1% ± 2.3%). Global CFR was highly reproducible (2.25 ± 0.56 vs. 2.22 ± 0.54, P = not statistically significant; mean difference, 1.3% ± 14.3%). Repeatability coefficients for global rest MBF were 0.033 (5.2%) and stress MBF 0.062 (4.5%) mL/min/g. Regional rest and stress MBF and CFR have shown good reproducibility. The average per sector repeatability coefficients for rest MBF were 0.056 (8.5%) and stress MBF 0.089 (6.3%) mL/min/g, and average repeatability coefficient for CFR was 0.25 (10.6%). The results

A Geo-referenced 3D model of the Juan de Fuca Slab and associated seismicity

Science.gov (United States)

Blair, J.L.; McCrory, P.A.; Oppenheimer, D.H.; Waldhauser, F.

2011-01-01

We present a Geographic Information System (GIS) of a new 3-dimensional (3D) model of the subducted Juan de Fuca Plate beneath western North America and associated seismicity of the Cascadia subduction system. The geo-referenced 3D model was constructed from weighted control points that integrate depth information from hypocenter locations and regional seismic velocity studies. We used the 3D model to differentiate earthquakes that occur above the Juan de Fuca Plate surface from earthquakes that occur below the plate surface. This GIS project of the Cascadia subduction system supersedes the one previously published by McCrory and others (2006). Our new slab model updates the model with new constraints. The most significant updates to the model include: (1) weighted control points to incorporate spatial uncertainty, (2) an additional gridded slab surface based on the Generic Mapping Tools (GMT) Surface program which constructs surfaces based on splines in tension (see expanded description below), (3) double-differenced hypocenter locations in northern California to better constrain slab location there, and (4) revised slab shape based on new hypocenter profiles that incorporate routine depth uncertainties as well as data from new seismic-reflection and seismic-refraction studies. We also provide a 3D fly-through animation of the model for use as a visualization tool.

Propagating wave in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph

Science.gov (United States)

Zhang, B.; Hou, Y. J.; Zhang, J.

2018-03-01

Aims: We aim to ascertain the physical parameters of a propagating wave over the solar disk detected by the Interface Region Imaging Spectrograph (IRIS). Methods: Using imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked bright spots to determine the parameters of a propagating transverse wave in active region (AR) loops triggered by activation of a filament. Deriving the Doppler velocity of Si IV line from spectral observations of IRIS, we have determined the rotating directions of active region loops which are relevant to the wave. Results: On 2015 December 19, a filament was located on the polarity inversion line of the NOAA AR 12470. The filament was activated and then caused a C1.1 two-ribbon flare. Between the flare ribbons, two rotation motions of a set of bright loops were observed to appear in turn with opposite directions. Following the end of the second rotation, a propagating wave and an associated transverse oscillation were detected in these bright loops. In 1400 Å channel, there was bright material flowing along the loops in a wave-like manner, with a period of 128 s and a mean amplitude of 880 km. For the transverse oscillation, we tracked a given loop and determine the transverse positions of the tracking loop in a limited longitudinal range. In both of 1400 Å and 171 Å channels, approximately four periods are distinguished during the transverse oscillation. The mean period of the oscillation is estimated as 143 s and the displacement amplitude as between 1370 km and 690 km. We interpret these oscillations as a propagating kink wave and obtain its speed of 1400 km s-1. Conclusions: Our observations reveal that a flare associated with filament activation could trigger a kink propagating wave in active region loops over the solar disk. Movies associated to Figs. 1-4 are available at http://https://www.aanda.org

Social referencing and child anxiety: the evolutionary based role of fathers' versus mothers' signals

NARCIS (Netherlands)

Möller, E.L.; Majdandžić, M.; Vriends, N.; Bögels, S.M.

2014-01-01

Children use signals from others to guide their behavior when confronted with potentially dangerous situations, so called social referencing. Due to evolutionary based different expertise of fathers and mothers, parents might be different social references for their children. The present study

Automated Segmentation of High-Resolution Photospheric Images of Active Regions

Science.gov (United States)

Yang, Meng; Tian, Yu; Rao, Changhui

2018-02-01

Due to the development of ground-based, large-aperture solar telescopes with adaptive optics (AO) resulting in increasing resolving ability, more accurate sunspot identifications and characterizations are required. In this article, we have developed a set of automated segmentation methods for high-resolution solar photospheric images. Firstly, a local-intensity-clustering level-set method is applied to roughly separate solar granulation and sunspots. Then reinitialization-free level-set evolution is adopted to adjust the boundaries of the photospheric patch; an adaptive intensity threshold is used to discriminate between umbra and penumbra; light bridges are selected according to their regional properties from candidates produced by morphological operations. The proposed method is applied to the solar high-resolution TiO 705.7-nm images taken by the 151-element AO system and Ground-Layer Adaptive Optics prototype system at the 1-m New Vacuum Solar Telescope of the Yunnan Observatory. Experimental results show that the method achieves satisfactory robustness and efficiency with low computational cost on high-resolution images. The method could also be applied to full-disk images, and the calculated sunspot areas correlate well with the data given by the National Oceanic and Atmospheric Administration (NOAA).

Central nervous system PET-CT imaging reveals regional impairments in pediatric patients with Wolfram syndrome.

Directory of Open Access Journals (Sweden)

Agnieszka Zmyslowska

Full Text Available Wolfram syndrome (WFS is inherited as an autosomal recessive disease with main clinical features of diabetes mellitus, optic atrophy, diabetes insipidus and deafness. However, various neurological defects may also be detected. The aim of this study was to evaluate aspects of brain structure and function using PET-CT (positron emission tomography and computed tomography and MRI (magnetic resonance imaging in pediatric patients with WFS. Regional changes in brain glucose metabolism were measured using standardized uptake values (SUVs based on images of (18F fluorodeoxyglucose (FDG uptake in 7 WFS patients aged 10.1-16.0 years (mean 12.9±2.4 and in 20 healthy children aged 3-17.9 years (mean 12.8±4.1. In all patients the diagnosis of WFS was confirmed by DNA sequencing of the WFS1 gene. Hierarchical clustering showed remarkable similarities of glucose uptake patterns among WFS patients and their differences from the control group. SUV data were subsequently standardized for age groups 13 years old to account for developmental differences. Reduced SUVs in WFS patients as compared to the control group for the bilateral brain regions such as occipital lobe (-1.24±1.20 vs. -0.13±1.05; p = 0.028 and cerebellum (-1.11±0.69 vs. -0.204±1.00; p = 0.036 were observed and the same tendency for cingulate (-1.13±1.05 vs. -0.15±1.12; p = 0.056, temporal lobe (-1.10±0.98 vs. -0.15±1.10; p = 0.057, parietal lobe (-1.06±1.20 vs. -0.08±1.08; p = 0.058, central region (-1.01±1.04 vs. -0.09±1.06; p = 0.060, basal ganglia (-1.05±0.74 vs. -0.20±1.07; p = 0.066 and mesial temporal lobe (-1.06±0.82 vs. -0.26±1.08; p = 0.087 was also noticed. After adjusting for multiple hypothesis testing, the differences in glucose uptake were non-significant. For the first time, regional differences in brain glucose metabolism among patients with WFS were shown using PET-CT imaging.

Summary: Update to ASTM guide E 1523 to charge control and charge referencing techniques in x-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Baer, D.R.

2005-01-01

An updated version of the American Society for Testing and Materials (ASTM) guide E 1523 to the methods to charge control and charge referencing techniques in x-ray photoelectron spectroscopy has been released by ASTM [Annual Book of ASTM Standards Surface Analysis (American Society for Testing and Materials, West Conshohocken, PA, 2004), Vol. 03.06]. The guide is meant to acquaint x-ray photoelectron spectroscopy (XPS) users with the various charge control and charge referencing techniques that are and have been used in the acquisition and interpretation of XPS data from surfaces of insulating specimens. The current guide has been expanded to include new references as well as recommendations for reporting information on charge control and charge referencing. The previous version of the document had been published in 1997 [D. R. Baer and K. D. Bomben, J. Vac. Sci. Technol. A 16, 754 (1998)

Romanization of Referencing Styles for Arts & Humanities Science Journals in Taiwan

Directory of Open Access Journals (Sweden)

Chang-Huei Lin

2016-12-01

Full Text Available Based on Big Three referecing styles guides, namely APA, Chicago (Turabian and MLA Style, this study discusses the citation formats in which have been applied and specified for scholarly references in non-English languages, especially in Chinese language scholarly writing. This study targets on those Taiwan journals, indexed by TSSCI, THCI Core, A&HCI, SSCI and Scopus, that use the Romanization of references in Chinese journal. By analyzing their notes for contributors and the real situation of application in the Chinese cited works. In respect of the aforementioned three major referencing styles and the rules made by journals themselves, the findings are as follows: the APA, Chicago, and MLA Styles should be revised according to the practical needs of citing non-English references; academic journal publishers need to specify and provide the guidelines and templates of romanizing references in respect of contributed articles; international citation index databases providers should stipulate and provide their description style for romanizing references, and the government and major academic institutes should put more efforts to assist local scholarly journals to cope with the reference romanization problems, even at promoting a kind of consistent Pinyin principle for referencing styles for Chinese journal publishing in Taiwan.

DactyLoc : A minimally geo-referenced WiFi+GSM-fingerprint-based localization method for positioning in urban spaces

DEFF Research Database (Denmark)

Cujia, Kristian; Wirz, Martin; Kjærgaard, Mikkel Baun

2012-01-01

Fingerprinting-based localization methods relying on WiFi and GSM information provide sufficient localization accuracy for many mobile phone applications. Most of the existing approaches require a training set consisting of geo-referenced fingerprints to build a reference database. We propose...... a collaborative, semi-supervised WiFi+GSM fingerprinting method where only a small fraction of all fingerprints needs to be geo-referenced. Our approach enables indexing of areas in the absence of GPS reception as often found in urban spaces and indoors without manual labeling of fingerprints. The method takes...

Ex-PRESS glaucoma filter: an MRI compatible metallic orbital foreign body imaged at 1.5 and 3 T

International Nuclear Information System (INIS)

Mabray, M.C.; Uzelac, A.; Talbott, J.F.; Lin, S.C.; Gean, A.D.

2015-01-01

Aim: To report on the MRI compatibility of the Ex-PRESS glaucoma filtration device, a tiny metallic implant placed into the anterior chamber of the eye that is much smaller than traditional glaucoma shunts, and to educate the radiology community regarding its appearance. Materials and methods: Seven patients with Ex-PRESS glaucoma filtration devices were identified that had undergone MRI at San Francisco General Hospital/University of California San Francisco Medical Center by searching and cross-referencing the radiology reporting system and the electronic medical record. MRI images were reviewed for artefact interfering with interpretation. Ophthalmology examinations were reviewed for evidence of complications. Results: Eighteen individual MRI examinations were performed during 12 unique MRI events on these 7 patients. 13/18 individual MRI examinations and 7/12 MRI events were performed at 3 T with the others performed at 1.5 T. Mean time from Ex-PRESS implantation to MRI was 17.5 months. Mean time from MRI to first ophthalmology examination was 1.1 months and from MRI to latest ophthalmology examination was 6.6 months. Susceptibility artefact did not interfere with image interpretation and no complications related to MRI were encountered. Conclusion: The Ex-PRESS glaucoma filtration device appears to be safe for MRI at 1.5 and 3 T and does not produce significant susceptibility artefact to affect diagnostic interpretation adversely. - Highlights: • The Ex-PRESS glaucoma filtration device is a tiny metallic orbital implant. • It can simulate a metallic orbital foreign body on imaging. • There is little information in the literature about it's MRI safety. • We report 18 MRIs performed on 7 patients including the first at 3 T. • Imaging appears to be safe at 1.5 and 3 T in patients with this device

Segmentation of Multi-Isotope Imaging Mass Spectrometry Data for Semi-Automatic Detection of Regions of Interest

Science.gov (United States)

Poczatek, J. Collin; Turck, Christoph W.; Lechene, Claude

2012-01-01

Multi-isotope imaging mass spectrometry (MIMS) associates secondary ion mass spectrometry (SIMS) with detection of several atomic masses, the use of stable isotopes as labels, and affiliated quantitative image-analysis software. By associating image and measure, MIMS allows one to obtain quantitative information about biological processes in sub-cellular domains. MIMS can be applied to a wide range of biomedical problems, in particular metabolism and cell fate [1], [2], [3]. In order to obtain morphologically pertinent data from MIMS images, we have to define regions of interest (ROIs). ROIs are drawn by hand, a tedious and time-consuming process. We have developed and successfully applied a support vector machine (SVM) for segmentation of MIMS images that allows fast, semi-automatic boundary detection of regions of interests. Using the SVM, high-quality ROIs (as compared to an expert's manual delineation) were obtained for 2 types of images derived from unrelated data sets. This automation simplifies, accelerates and improves the post-processing analysis of MIMS images. This approach has been integrated into “Open MIMS,” an ImageJ-plugin for comprehensive analysis of MIMS images that is available online at http://www.nrims.hms.harvard.edu/NRIMS_ImageJ.php. PMID:22347386

Penumbral imaging with multi-penumbral-apertures and its heuristic reconstruction for nuclear reaction region diagnostics

International Nuclear Information System (INIS)

Ueda, Tatsuki; Fujioka, Shinsuke; Nishimura, Hiroaki; Nozaki, Shinya; Chen Yenwei

2010-01-01

Imaging of nuclear reaction region is important to clarify heating mechanism in a fast-ignition plasma. The nuclear reaction region can be identified by hard x-ray and neutron images, which are emanated from the heated region. We proposed a novel penumbral imaging that is suitable for imaging quanta having strong penetrating power, such as hard x ray and neutron. Using multiple penumbral apertures arranged with M-sequence leads to two orders of magnitude higher detection efficiency than that with a single aperture. In addition, a heuristic method was introduced to a image reconstruction procedure for reducing artifacts caused by noise in a penumbral image. A proof-of-principle experiment indicates that the proposed imaging is superior to the conventional one.

Geo-referenced modelling of metal concentrations in river basins at the catchment scale

Science.gov (United States)

Hüffmeyer, N.; Berlekamp, J.; Klasmeier, J.

2009-04-01

1. Introduction The European Water Framework Directive demands the good ecological and chemical state of surface waters [1]. This implies the reduction of unwanted metal concentrations in surface waters. To define reasonable environmental target values and to develop promising mitigation strategies a detailed exposure assessment is required. This includes the identification of emission sources and the evaluation of their effect on local and regional surface water concentrations. Point source emissions via municipal or industrial wastewater that collect metal loads from a wide variety of applications and products are important anthropogenic pathways into receiving waters. Natural background and historical influences from ore-mining activities may be another important factor. Non-point emissions occur via surface runoff and erosion from drained land area. Besides deposition metals can be deposited by fertilizer application or the use of metal products such as wires or metal fences. Surface water concentrations vary according to the emission strength of sources located nearby and upstream of the considered location. A direct link between specific emission sources and pathways on the one hand and observed concentrations can hardly be established by monitoring alone. Geo-referenced models such as GREAT-ER (Geo-referenced Regional Exposure Assessment Tool for European Rivers) deliver spatially resolved concentrations in a whole river basin and allow for evaluating the causal relationship between specific emissions and resulting concentrations. This study summarizes the results of investigations for the metals zinc and copper in three German catchments. 2. The model GREAT-ER The geo-referenced model GREAT-ER has originally been developed to simulate and assess chemical burden of European river systems from multiple emission sources [2]. Emission loads from private households and rainwater runoff are individually estimated based on average consumption figures, runoff rates

Detection of protein-small molecule binding using a self-referencing external cavity laser biosensor.

Science.gov (United States)

Meng Zhang; Peh, Jessie; Hergenrother, Paul J; Cunningham, Brian T

2014-01-01

High throughput screening of protein-small molecule binding interactions using label-free optical biosensors is challenging, as the detected signals are often similar in magnitude to experimental noise. Here, we describe a novel self-referencing external cavity laser (ECL) biosensor approach that achieves high resolution and high sensitivity, while eliminating thermal noise with sub-picometer wavelength accuracy. Using the self-referencing ECL biosensor, we demonstrate detection of binding between small molecules and a variety of immobilized protein targets with binding affinities or inhibition constants in the sub-nanomolar to low micromolar range. The demonstrated ability to perform detection in the presence of several interfering compounds opens the potential for increasing the throughput of the approach. As an example application, we performed a "needle-in-the-haystack" screen for inhibitors against carbonic anhydrase isozyme II (CA II), in which known inhibitors are clearly differentiated from inactive molecules within a compound library.

A differential weak measurement system based on Sagnac interferometer for self-referencing biomolecule detection

Science.gov (United States)

Li, Dongmei; Guan, Tian; He, Yonghong; He, Qinghua; Zhang, Yilong; Wang, Xiangnan; Shen, Zhiyuan; Yang, Yuxuan; Qiao, Zhen; Ji, Yanhong

2017-12-01

A differential weak measurement system was presented, exhibiting the self-referencing function for biomolecule real time detection as a label-free optical biosensor. We built a Sagnac interferometer, which limited horizontal (H) and vertical (V) polarization to propagating along the common path but in opposite directions to realize weak measurements with two measuring channels installed in two corners of this Sagnac interferometer. By introducing two half wave plates into the system alternately with the two channels to convert between H and V polarization, we obtained a differential measurement for phase delay, which could quantitatively characterize the refractive index change corresponding to the concentration of samples in the channels. With this system, a real time monitor of molecule concentration in the dialysis process was accomplished, demonstrating the function of self-referencing, which is important for optical label-free molecule detection in a complex biological sample solution.

Cellular Phone Towers, Tower locations and attributes generated from FCC anntenna registration database. Tower data was cross referenced with county zoning special use permits., Published in 2008, 1:600 (1in=50ft) scale, Waupaca County Government.

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Cellular Phone Towers dataset current as of 2008. Tower locations and attributes generated from FCC anntenna registration database. Tower data was cross referenced...

HIGH-RESOLUTION IMAGING OF THE ATLBS REGIONS: THE RADIO SOURCE COUNTS

Energy Technology Data Exchange (ETDEWEB)

Thorat, K.; Subrahmanyan, R.; Saripalli, L.; Ekers, R. D., E-mail: kshitij@rri.res.in [Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560080 (India)

2013-01-01

The Australia Telescope Low-brightness Survey (ATLBS) regions have been mosaic imaged at a radio frequency of 1.4 GHz with 6'' angular resolution and 72 {mu}Jy beam{sup -1} rms noise. The images (centered at R.A. 00{sup h}35{sup m}00{sup s}, decl. -67 Degree-Sign 00'00'' and R.A. 00{sup h}59{sup m}17{sup s}, decl. -67 Degree-Sign 00'00'', J2000 epoch) cover 8.42 deg{sup 2} sky area and have no artifacts or imaging errors above the image thermal noise. Multi-resolution radio and optical r-band images (made using the 4 m CTIO Blanco telescope) were used to recognize multi-component sources and prepare a source list; the detection threshold was 0.38 mJy in a low-resolution radio image made with beam FWHM of 50''. Radio source counts in the flux density range 0.4-8.7 mJy are estimated, with corrections applied for noise bias, effective area correction, and resolution bias. The resolution bias is mitigated using low-resolution radio images, while effects of source confusion are removed by using high-resolution images for identifying blended sources. Below 1 mJy the ATLBS counts are systematically lower than the previous estimates. Showing no evidence for an upturn down to 0.4 mJy, they do not require any changes in the radio source population down to the limit of the survey. The work suggests that automated image analysis for counts may be dependent on the ability of the imaging to reproduce connecting emission with low surface brightness and on the ability of the algorithm to recognize sources, which may require that source finding algorithms effectively work with multi-resolution and multi-wavelength data. The work underscores the importance of using source lists-as opposed to component lists-and correcting for the noise bias in order to precisely estimate counts close to the image noise and determine the upturn at sub-mJy flux density.

MRS algorithm: a new method for searching myocardial region in SPECT myocardial perfusion images.

Science.gov (United States)

He, Yuan-Lie; Tian, Lian-Fang; Chen, Ping; Li, Bin; Mao, Zhong-Yuan

2005-10-01

First, the necessity of automatically segmenting myocardium from myocardial SPECT image is discussed in Section 1. To eliminate the influence of the background, the optimal threshold segmentation method modified for the MRS algorithm is explained in Section 2. Then, the image erosion structure is applied to identify the myocardium region and the liver region. The contour tracing method is introduced to extract the myocardial contour. To locate the centriod of the myocardium, the myocardial centriod searching method is developed. The protocol of the MRS algorithm is summarized in Section 6. The performance of the MRS algorithm is investigated and the conclusion is drawn in Section 7. Finally, the importance of the MRS algorithm and the improvement of the MRS algorithm are discussed.

Fibre optics wavemeters calibration using a self-referenced optical frequency comb

Energy Technology Data Exchange (ETDEWEB)

Galindo-Santos, J.; Velasco, A. V.; Corredera, P. [Instituto de Óptica IO-CSIC, C/Serrano 121, 28006 Madrid (Spain)

2015-01-15

Self-referenced optical frequency combs enable the measurement of optical frequencies with a very high accuracy, achieving uncertainties close to the atomic clock used as reference (<10{sup −13} s). In this paper, we present the technique for the measurement of laser frequencies for optical communications followed at IO-CSIC and its application to the calibration of two wavemeters in the 1.5 μm optical communication window. Calibration uncertainties down to 12 MHz and 59 MHz were obtained, respectively, for each of the devices. Furthermore, the long-term behaviour of the higher resolution wavemeter was studied during a 750 h period of sustained operation, exhibiting a dispersion in the measurements of 7.72 MHz. Temperature dependence of the device was analysed, enabling to further reduce dispersion down to a 2.15 MHz range, with no significant temporal deviations.

Ecological sensitivity of the Persian Gulf coastal region (Case study ...

African Journals Online (AJOL)

geo-referencing photo mosaic Land Sat Satellite images (2003) and IRS' (2004) were taken and basic maps of two influential areas were evaluated within the above mentioned limits which included the coastal village boundaries. The coastal line of the area being evaluated (set back line) was 673.62 kms comprising an ...

Comparison of pure and hybrid iterative reconstruction techniques with conventional filtered back projection: Image quality assessment in the cervicothoracic region

International Nuclear Information System (INIS)

Katsura, Masaki; Sato, Jiro; Akahane, Masaaki; Matsuda, Izuru; Ishida, Masanori; Yasaka, Koichiro; Kunimatsu, Akira; Ohtomo, Kuni

2013-01-01

Objectives: To evaluate the impact on image quality of three different image reconstruction techniques in the cervicothoracic region: model-based iterative reconstruction (MBIR), adaptive statistical iterative reconstruction (ASIR), and filtered back projection (FBP). Methods: Forty-four patients underwent unenhanced standard-of-care clinical computed tomography (CT) examinations which included the cervicothoracic region with a 64-row multidetector CT scanner. Images were reconstructed with FBP, 50% ASIR-FBP blending (ASIR50), and MBIR. Two radiologists assessed the cervicothoracic region in a blinded manner for streak artifacts, pixilated blotchy appearances, critical reproduction of visually sharp anatomical structures (thyroid gland, common carotid artery, and esophagus), and overall diagnostic acceptability. Objective image noise was measured in the internal jugular vein. Data were analyzed using the sign test and pair-wise Student's t-test. Results: MBIR images had significant lower quantitative image noise (8.88 ± 1.32) compared to ASIR images (18.63 ± 4.19, P 0.9 for ASIR vs. FBP for both readers). MBIR images were all diagnostically acceptable. Unique features of MBIR images included pixilated blotchy appearances, which did not adversely affect diagnostic acceptability. Conclusions: MBIR significantly improves image noise and streak artifacts of the cervicothoracic region over ASIR and FBP. MBIR is expected to enhance the value of CT examinations for areas where image noise and streak artifacts are problematic

Direct observation of the leakage current in epitaxial diamond Schottky barrier devices by conductive-probe atomic force microscopy and Raman imaging

Science.gov (United States)

Alvarez, J.; Boutchich, M.; Kleider, J. P.; Teraji, T.; Koide, Y.

2014-09-01

The origin of the high leakage current measured in several vertical-type diamond Schottky devices is conjointly investigated by conducting probe atomic force microscopy and confocal micro-Raman/photoluminescence imaging analysis. Local areas characterized by a strong decrease of the local resistance (5-6 orders of magnitude drop) with respect to their close surrounding have been identified in several different regions of the sample surface. The same local areas, also referenced as electrical hot-spots, reveal a slightly constrained diamond lattice and three dominant Raman bands in the low-wavenumber region (590, 914 and 1040 cm-1). These latter bands are usually assigned to the vibrational modes involving boron impurities and its possible complexes that can electrically act as traps for charge carriers. Local current-voltage measurements performed at the hot-spots point out a trap-filled-limited current as the main conduction mechanism favouring the leakage current in the Schottky devices.

Direct observation of the leakage current in epitaxial diamond Schottky barrier devices by conductive-probe atomic force microscopy and Raman imaging

International Nuclear Information System (INIS)

Alvarez, J; Boutchich, M; Kleider, J P; Teraji, T; Koide, Y

2014-01-01

The origin of the high leakage current measured in several vertical-type diamond Schottky devices is conjointly investigated by conducting probe atomic force microscopy and confocal micro-Raman/photoluminescence imaging analysis. Local areas characterized by a strong decrease of the local resistance (5–6 orders of magnitude drop) with respect to their close surrounding have been identified in several different regions of the sample surface. The same local areas, also referenced as electrical hot-spots, reveal a slightly constrained diamond lattice and three dominant Raman bands in the low-wavenumber region (590, 914 and 1040 cm −1 ). These latter bands are usually assigned to the vibrational modes involving boron impurities and its possible complexes that can electrically act as traps for charge carriers. Local current–voltage measurements performed at the hot-spots point out a trap-filled-limited current as the main conduction mechanism favouring the leakage current in the Schottky devices. (paper)

Thermography imaging during static and controlled thermoregulation in complex regional pain syndrome type 1: diagnostic value and involvement of the central sympathetic system

Directory of Open Access Journals (Sweden)

Westra Mirjam

2006-05-01

Full Text Available Abstract Background Complex Regional Pain Syndrome type 1 (CRPS1 is a clinical diagnosis based on criteria describing symptoms of the disease. The main aim of the present study was to compare the sensitivity and specificity of calculation methods used to assess thermographic images (infrared imaging obtained during temperature provocation. The secondary objective was to obtain information about the involvement of the sympathetic system in CRPS1. Methods We studied 12 patients in whom CRPS1 was diagnosed according to the criteria of Bruehl. High and low whole body cooling and warming induced and reduced sympathetic vasoconstrictor activity. The degree of vasoconstrictor activity in both hands was monitored using a videothermograph. The sensitivity and specificity of the calculation methods used to assess the thermographic images were calculated. Results The temperature difference between the hands in the CRPS patients increases significantly when the sympathetic system is provoked. At both the maximum and minimum vasoconstriction no significant differences were found in fingertip temperatures between both hands. Conclusion The majority of CRPS1 patients do not show maximal obtainable temperature differences between the involved and contralateral extremity at room temperature (static measurement. During cold and warm temperature challenges this temperature difference increases significantly. As a result a higher sensitivity and specificity could be achieved in the diagnosis of CRPS1. These findings suggest that the sympathetic efferent system is involved in CRPS1.

Fast regional readout CMOS Image Sensor for dynamic MLC tracking

Science.gov (United States)

Zin, H.; Harris, E.; Osmond, J.; Evans, P.

2014-03-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ~400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Fast regional readout CMOS image sensor for dynamic MLC tracking

International Nuclear Information System (INIS)

Zin, H; Harris, E; Osmond, J; Evans, P

2014-01-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ∼400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Spirometrically gated 133Xe ventilation imaging and phase analysis for assessment of regional lung function

International Nuclear Information System (INIS)

Inoue, Tomio

1984-01-01

The purpose of this study is to develop the technique of performing spirometrically gated 133 Xe ventilation imaging and to evaluate its clinical usefulness for the assessmentof regional ventilatory function in various lung diseases. Patients rebreathe d 133 Xe gas through the system with constant rates signaled by a metronom. The trigger signals from the patients were recorded in a minicomputer for 60 respiratory cycles simultaneously with posterior lung images. Functional images (phase analysis images) indicating phase and amplitude of regional ventilation were constructed by the first harmonic Fourier analysis. Materials included 13 normal volunteers and patients with COPD (24), lung cancer (5), pulmonary embolism (4) and others (20). In normal controls, phase analysis images before respiratory motion correction revealed gradual decrease in amplitude from base to apex with uniform phase distribution. The amplitude and phase distribution after respiratory motion correction became even more uniform. In patients with COPD, phase analysis images showed asymmetrical and irregular amplitude distribution with non-uniform phase distribution. The standard deviation (S.D.) of phase histogram correlated well with FEVsub(1.0)% (r=0.71, p<0.001) and down slope of flowvolume curve (r=0.55, p<0.001), and less prominently with %VC (r=0.42, p<0.01). Mean S.D. in patients with COPD (12.3+-6.5 degree, mean+-1 s.d.) was significantly larger than in normal controls (6.3+-1.5). Amplitude profile curve analysis revealed 83% sensitivity for the detection of abnormal spirometric respiratory function test. Data aquisition and processing of present method are rapid and easy to perform. The phase analysis of the gated ventilation images should prove useful in the clinical evaluation of patients with uneven ventilation such as COPD. (J.P.N.)

Comparison of pure and hybrid iterative reconstruction techniques with conventional filtered back projection: Image quality assessment in the cervicothoracic region

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Katsura, Masaki, E-mail: mkatsura-tky@umin.ac.jp [Department of Radiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 (Japan); Sato, Jiro; Akahane, Masaaki; Matsuda, Izuru; Ishida, Masanori; Yasaka, Koichiro; Kunimatsu, Akira; Ohtomo, Kuni [Department of Radiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 (Japan)

2013-02-15

Objectives: To evaluate the impact on image quality of three different image reconstruction techniques in the cervicothoracic region: model-based iterative reconstruction (MBIR), adaptive statistical iterative reconstruction (ASIR), and filtered back projection (FBP). Methods: Forty-four patients underwent unenhanced standard-of-care clinical computed tomography (CT) examinations which included the cervicothoracic region with a 64-row multidetector CT scanner. Images were reconstructed with FBP, 50% ASIR-FBP blending (ASIR50), and MBIR. Two radiologists assessed the cervicothoracic region in a blinded manner for streak artifacts, pixilated blotchy appearances, critical reproduction of visually sharp anatomical structures (thyroid gland, common carotid artery, and esophagus), and overall diagnostic acceptability. Objective image noise was measured in the internal jugular vein. Data were analyzed using the sign test and pair-wise Student's t-test. Results: MBIR images had significant lower quantitative image noise (8.88 ± 1.32) compared to ASIR images (18.63 ± 4.19, P < 0.01) and FBP images (26.52 ± 5.8, P < 0.01). Significant improvements in streak artifacts of the cervicothoracic region were observed with the use of MBIR (P < 0.001 each for MBIR vs. the other two image data sets for both readers), while no significant difference was observed between ASIR and FBP (P > 0.9 for ASIR vs. FBP for both readers). MBIR images were all diagnostically acceptable. Unique features of MBIR images included pixilated blotchy appearances, which did not adversely affect diagnostic acceptability. Conclusions: MBIR significantly improves image noise and streak artifacts of the cervicothoracic region over ASIR and FBP. MBIR is expected to enhance the value of CT examinations for areas where image noise and streak artifacts are problematic.

Prevalence of Soft Tissue Calcifications in CBCT Images of Mandibular Region.

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Khojastepour, Leila; Haghnegahdar, Abdolaziz; Sayar, Hamed

2017-06-01

Most of the soft tissue calcifications within the head and neck region might not be accompanied by clinical symptoms but may indicate some pathological conditions. The aim of this research was to determine the prevalence of soft tissue calcifications in cone beam computed tomography (CBCT) images of mandibular region. In this cross sectional study the CBCT images of 602 patients including 294 men and 308 women with mean age 41.38±15.18 years were evaluated regarding the presence, anatomical location; type (single or multiple) and size of soft tissue calcification in mandibular region. All CBCT images were acquired by NewTom VGi scanner. Odds ratio and chi-square tests were used for data analysis and p < 0.05 was considered to be statistically significant. 156 out of 602 patients had at least one soft tissue calcification in their mandibular region (25.9%. of studied population with mean age 51.7±18.03 years). Men showed significantly higher rate of soft tissue calcification than women (30.3% vs. 21.8%). Soft tissue calcification was predominantly seen at posterior region of the mandible (88%) and most of them were single (60.7%). The prevalence of soft tissue calcification increased with age. Most of the detected soft tissue calcifications were smaller than 3mm (90%). Soft tissue calcifications in mandibular area were a relatively common finding especially in posterior region and more likely to happen in men and in older age group.

Digital Sequences and a Time Reversal-Based Impact Region Imaging and Localization Method

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Qiu, Lei; Yuan, Shenfang; Mei, Hanfei; Qian, Weifeng

2013-01-01

To reduce time and cost of damage inspection, on-line impact monitoring of aircraft composite structures is needed. A digital monitor based on an array of piezoelectric transducers (PZTs) is developed to record the impact region of impacts on-line. It is small in size, lightweight and has low power consumption, but there are two problems with the impact alarm region localization method of the digital monitor at the current stage. The first one is that the accuracy rate of the impact alarm region localization is low, especially on complex composite structures. The second problem is that the area of impact alarm region is large when a large scale structure is monitored and the number of PZTs is limited which increases the time and cost of damage inspections. To solve the two problems, an impact alarm region imaging and localization method based on digital sequences and time reversal is proposed. In this method, the frequency band of impact response signals is estimated based on the digital sequences first. Then, characteristic signals of impact response signals are constructed by sinusoidal modulation signals. Finally, the phase synthesis time reversal impact imaging method is adopted to obtain the impact region image. Depending on the image, an error ellipse is generated to give out the final impact alarm region. A validation experiment is implemented on a complex composite wing box of a real aircraft. The validation results show that the accuracy rate of impact alarm region localization is approximately 100%. The area of impact alarm region can be reduced and the number of PZTs needed to cover the same impact monitoring region is reduced by more than a half. PMID:24084123

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer's Disease: Results from the DIAN Study Group.

Directory of Open Access Journals (Sweden)

Yi Su

Full Text Available Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer's Network (DIAN, an autosomal dominant Alzheimer's disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer's disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted.

Noninvasive referencing of intraocular tumors for external beam radiation therapy using optical coherence tomography: A proof of concept

International Nuclear Information System (INIS)

Rüegsegger, Michael B.; Steiner, Patrick; Kowal, Jens H.; Geiser, Dominik; Pica, Alessia; Aebersold, Daniel M.

2014-01-01

Purpose: External beam radiation therapy is currently considered the most common treatment modality for intraocular tumors. Localization of the tumor and efficient compensation of tumor misalignment with respect to the radiation beam are crucial. According to the state of the art procedure, localization of the target volume is indirectly performed by the invasive surgical implantation of radiopaque clips or is limited to positioning the head using stereoscopic radiographies. This work represents a proof-of-concept for direct and noninvasive tumor referencing based on anterior eye topography acquired using optical coherence tomography (OCT). Methods: A prototype of a head-mounted device has been developed for automatic monitoring of tumor position and orientation in the isocentric reference frame for LINAC based treatment of intraocular tumors. Noninvasive tumor referencing is performed with six degrees of freedom based on anterior eye topography acquired using OCT and registration of a statistical eye model. The proposed prototype was tested based on enucleated pig eyes and registration accuracy was measured by comparison of the resulting transformation with tilt and torsion angles manually induced using a custom-made test bench. Results: Validation based on 12 enucleated pig eyes revealed an overall average registration error of 0.26 ± 0.08° in 87 ± 0.7 ms for tilting and 0.52 ± 0.03° in 94 ± 1.4 ms for torsion. Furthermore, dependency of sampling density on mean registration error was quantitatively assessed. Conclusions: The tumor referencing method presented in combination with the statistical eye model introduced in the past has the potential to enable noninvasive treatment and may improve quality, efficacy, and flexibility of external beam radiotherapy of intraocular tumors

A Method for Automatic Extracting Intracranial Region in MR Brain Image

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Kurokawa, Keiji; Miura, Shin; Nishida, Makoto; Kageyama, Yoichi; Namura, Ikuro

It is well known that temporal lobe in MR brain image is in use for estimating the grade of Alzheimer-type dementia. It is difficult to use only region of temporal lobe for estimating the grade of Alzheimer-type dementia. From the standpoint for supporting the medical specialists, this paper proposes a data processing approach on the automatic extraction of the intracranial region from the MR brain image. The method is able to eliminate the cranium region with the laplacian histogram method and the brainstem with the feature points which are related to the observations given by a medical specialist. In order to examine the usefulness of the proposed approach, the percentage of the temporal lobe in the intracranial region was calculated. As a result, the percentage of temporal lobe in the intracranial region on the process of the grade was in agreement with the visual sense standards of temporal lobe atrophy given by the medical specialist. It became clear that intracranial region extracted by the proposed method was good for estimating the grade of Alzheimer-type dementia.

Evaluation of regional pulmonary ventilation by videodensitometry using a new X-ray image processor

International Nuclear Information System (INIS)

Fujii, Tadashige; Kanai, Hisakata; Handa, Kenjiro; Takizawa, Masaomi

1988-01-01

A new video image processing device has been produced in order to assess regional pulmonary ventilation. This device consists of a microcomputer, digital frame memory, digitizer, videomonitor, joystick and videotape recorder. The changing radiographic density of the lungs during deep respiration and forced expiration is recorded by the videotape recorder, which is connected to an image intensifier television system. This device allows the examining physician to place 6 rectangular windows of variable size over any portion of the video image using the joystick, and to measure the brightness level within these windows simultaneously. It is very characteristic that the video-densitometric curve and marks of the windows are superimposed on the frozen final frame of the sampled images. By this procedure, fair videodensigrams were obtained in various respiratory diseases, and reduction of ventilatory amplitude was shown in the hypoventilatory regions. The joint use of video-densitometry and perfusion lung scintigraphy provided helpful information concerning the regional ventilation/perfusion relationship. The videodensitometry of the lung the new X-ray image processor offers routine screening evaluation of regional pulmonary ventilation abnormalities over the entire video image of the lungs without more effort required of the patients. (author)

Study of regional cerebral blood flow SPECT imaging for sudden sensorineural deafness

International Nuclear Information System (INIS)

Xie Changhui; Kui Xixiao; Xiong Qibin; Wen Hui; Xie Jiabiao

1998-01-01

Purpose: To study the clinical value of regional cerebral blood flow (rCBF) SPECT imaging for sudden sensorineural deafness (SSD). Methods: 10 normal persons, 19 conductive deafness and 31 SSD patients were examined by rCBF SPECT imaging, and compared with X CT at the same time. All SSD patients were followed up for 6∼12 months with repeated rCBF SPECT imaging. Results: 1) The radioactivity of diseased and normal horizontal temporal gyrus ratio (T/NT) in SSD patients was the lowest among three groups (P < 0.01). 2) The sensitivity (80.6%) and accurate rate (88.3%) of rCBF SPECT imaging in SSD patients were much higher than those of CT (3.2% and 50%, P < 0.01). 3) There was a significant correlation between degree of deafness and T/NT in SSD patients. 4) Good prognosis of SSD patients with normal rCBF SPECT was found. 5) The rCBF SPECT had close concordance between rCBF SPECT imaging and clinical prognosis (84.6%). Conclusions: rCBF SPECT imaging was superior to X CT in diagnosis of SSD and played an important clinical role

New Pn and Sn tomographic images of the uppermost mantle beneath the Mediterranean region

Science.gov (United States)

Gil, A.; Díaz, J.; Gallart, J.

2012-04-01

We present here new images of the seismic velocity and anisotropy variations in the uppermost mantle beneath the Mediterranean region, compiled from inversion of Pn and Sn phases. The method of Hearn (1996) has been applied to Pn and Sn lectures from the catalogs of the International Seismological Center and the Spanish Instituto Geografico Nacional. A total of 1,172,293 Pn arrivals coming from 16,527 earthquakes recorded at 1,657 stations with epicentral distances between 220 km and 1400 km have been retained (331,567 arrivals from 15,487events at 961 stations for Sn). Our results, grossly consistent with available 3D tomography images, show significant features well correlated with surface geology. The Pn velocities are high (>8.2 km/s) beneath major sedimentary basins (western Alboran Sea, Valencia Trough, Adriatic Sea, Aquitaine, Guadalquivir, Rharb, Aquitaine and Po basins), and low (Islands, probably related to a thermal anomaly associated to the westward displacement of the Alboran block along the Emile Baudot escarpment 16 Ma ago. The Pn anisotropic image shows consistent orientations sub-parallel to major orogenic structures, such as Betics, Apennines, Calabrian Arc and Alps. The station delays beneath Betic and Rif ranges are strongly negative, suggesting the presence of crustal thickening all along the Gibraltar Arc. However, only the Betics have a very strong low-velocity anomaly and a pronounced anisotropy pattern. The Sn tomographic image correlates well with the Pn image, even if some relevant differences can be observed beneath particular regions.

Polarization images of the inner regions of Comet Halley

International Nuclear Information System (INIS)

Eaton, N.; Scarrott, S.M.; Warren-Smith, R.F.

1988-01-01

The present CCD polarimeter images of intensity and polarization within the near-nucleus regions of Comet Halley show the occurrence of dust jets on two days in January, 1986, which exhibit increased polarizations above the level of the surrounding coma. Three possible reasons for the enhanced polarization in the jets are considered, assuming that the polarization increase is due to dust grains: (1) the size distribution of the grains could be different from the surrounding coma; (2) the material of the grains could have a different refractive index; and (3) the ratio of dust to gas emission could be different in the jets. 13 references

Proton MR spectroscopic imaging of basal ganglia and thalamus in neurofibromatosis type 1: correlation with T2 hyperintensities

International Nuclear Information System (INIS)

Barbier, Charlotte; Barantin, Laurent; Chabernaud, Camille; Bertrand, Philippe; Sembely, Catherine; Sirinelli, Dominique; Castelnau, Pierre; Cottier, Jean-Philippe

2011-01-01

Neurofibromatosis type 1 (NF1) is frequently associated with hyperintense lesions on T2-weighted images called ''unidentified bright objects'' (UBO). To better characterize the functional significance of UBO, we investigate the basal ganglia and thalamus using spectroscopic imaging in children with NF1 and compare the results to anomalies observed on T2-weighted images. Magnetic resonance (MR) data of 25 children with NF1 were analyzed. On the basis of T2-weighted images analysis, two groups were identified: one with normal MR imaging (UBO- group; n = 10) and one with UBO (UBO+ group; n = 15). Within the UBO+ group, a subpopulation of patients (n = 5) only had lesions of the basal ganglia. We analyzed herein seven regions of interest (ROIs) for each side: caudate nucleus, capsulo-lenticular region, lateral and posterior thalamus, thalamus (lateral and posterior voxels combined), putamen, and striatum. For each ROI, a spectrum of the metabolites and their ratio was obtained. Patients with abnormalities on T2-weighted images had significantly lower NAA/Cr, NAA/Cho, and NAA/mI ratios in the lateral right thalamus compared with patients with normal T2. These abnormal spectroscopic findings were not observed in capsulo-lenticular regions that had UBO but in the thalamus region that was devoid of UBO. Multivoxel spectroscopic imaging using short-time echo showed spectroscopic abnormalities in the right thalamus of NF1 patients harboring UBO, which were mainly located in the basal ganglia. This finding could reflect the anatomical and functional interactions of these regions. (orig.)

P1-27: Localizing Regions Activated by Surface Gloss in Macaque Visual Cortex by fMRI

Directory of Open Access Journals (Sweden)

Gouki Okazawa

2012-10-01

Full Text Available Surface properties of objects such as gloss provide important information about the states or materials of objects in our visual experiences. Previous studies have shown that there are cortical regions responding to shapes, colors, faces etc. in the macaque visual cortex. However, we still lack the information about where the surface properties are processed in the macaque visual cortex. In this study, we examined whether there are regions activated by surface gloss, an important surface property, in the macaque visual cortex by using functional magnetic resonance imaging (fMRI. We trained two monkeys to fixate on a small spot on the screen in MRI scanner, while the images of glossy and matte objects were presented. As a control condition for low-level image features, such as spatial frequency or luminance contrast, we generated scrambled images by locally randomizing the luminance phases of images using wavelet filters. By contrasting the responses to glossy images to those to matte and scrambled images, we found the activation in wide regions along the ventral visual pathway including V1, V2, V3, V4, and the posterior part of the inferior temporal (IT cortex. In one monkey, we also found the activations in the central part of IT cortex. In another control experiment, we manipulated the image contrasts and found that the responses in these regions cannot be explained simply by the image contrasts. These results suggest that surface gloss is processed along the ventral pathway and, in the IT cortex there are distinct regions processing surface gloss.

Linear single-step image reconstruction in the presence of nonscattering regions

Science.gov (United States)

Dehghani, H.; Delpy, D. T.

2002-06-01

There is growing interest in the use of near-infrared spectroscopy for the noninvasive determination of the oxygenation level within biological tissue. Stemming from this application, there has been further research in using this technique for obtaining tomographic images of the neonatal head, with the view of determining the level of oxygenated and deoxygenated blood within the brain. Because of computational complexity, methods used for numerical modeling of photon transfer within tissue have usually been limited to the diffusion approximation of the Boltzmann transport equation. The diffusion approximation, however, is not valid in regions of low scatter, such as the cerebrospinal fluid. Methods have been proposed for dealing with nonscattering regions within diffusing materials through the use of a radiosity-diffusion model. Currently, this new model assumes prior knowledge of the void region; therefore it is instructive to examine the errors introduced in applying a simple diffusion-based reconstruction scheme in cases where a nonscattering region exists. We present reconstructed images, using linear algorithms, of models that contain a nonscattering region within a diffusing material. The forward data are calculated by using the radiosity-diffusion model, and the inverse problem is solved by using either the radiosity-diffusion model or the diffusion-only model. When using data from a model containing a clear layer and reconstructing with the correct model, one can reconstruct the anomaly, but the qualitative accuracy and the position of the reconstructed anomaly depend on the size and the position of the clear regions. If the inverse model has no information about the clear regions (i.e., it is a purely diffusing model), an anomaly can be reconstructed, but the resulting image has very poor qualitative accuracy and poor localization of the anomaly. The errors in quantitative and localization accuracies depend on the size and location of the clear regions.

Dynamic segmentation to estimate vine vigor from ground images

OpenAIRE

Sáiz Rubio, Verónica; Rovira Más, Francisco

2012-01-01

[EN] The geographic information required to implement precision viticulture applications in real fields has led to the extensive use of remote sensing and airborne imagery. While advantageous because they cover large areas and provide diverse radiometric data, they are unreachable to most of medium-size Spanish growers who cannot afford such image sourcing. This research develops a new methodology to generate globally-referenced vigor maps in vineyards from ground images taken wit...

Dynamic segmentation to estimate vine vigor from ground images

OpenAIRE

Sáiz-Rubio, V.; Rovira-Más, F.

2012-01-01

The geographic information required to implement precision viticulture applications in real fields has led to the extensive use of remote sensing and airborne imagery. While advantageous because they cover large areas and provide diverse radiometric data, they are unreachable to most of medium-size Spanish growers who cannot afford such image sourcing. This research develops a new methodology to generate globally-referenced vigor maps in vineyards from ground images taken with a camera mounte...

STUDY OF AUTOMATIC IMAGE RECTIFICATION AND REGISTRATION OF SCANNED HISTORICAL AERIAL PHOTOGRAPHS

Directory of Open Access Journals (Sweden)

H. R. Chen

2016-06-01

Full Text Available Historical aerial photographs directly provide good evidences of past times. The Research Center for Humanities and Social Sciences (RCHSS of Taiwan Academia Sinica has collected and scanned numerous historical maps and aerial images of Taiwan and China. Some maps or images have been geo-referenced manually, but most of historical aerial images have not been registered since there are no GPS or IMU data for orientation assisting in the past. In our research, we developed an automatic process of matching historical aerial images by SIFT (Scale Invariant Feature Transform for handling the great quantity of images by computer vision. SIFT is one of the most popular method of image feature extracting and matching. This algorithm extracts extreme values in scale space into invariant image features, which are robust to changing in rotation scale, noise, and illumination. We also use RANSAC (Random sample consensus to remove outliers, and obtain good conjugated points between photographs. Finally, we manually add control points for registration through least square adjustment based on collinear equation. In the future, we can use image feature points of more photographs to build control image database. Every new image will be treated as query image. If feature points of query image match the features in database, it means that the query image probably is overlapped with control images.With the updating of database, more and more query image can be matched and aligned automatically. Other research about multi-time period environmental changes can be investigated with those geo-referenced temporal spatial data.

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer’s Disease: Results from the DIAN Study Group

Science.gov (United States)

Su, Yi; Blazey, Tyler M.; Owen, Christopher J.; Christensen, Jon J.; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C.; Ances, Beau M.; Snyder, Abraham Z.; Cash, Lisa A.; Koeppe, Robert A.; Klunk, William E.; Galasko, Douglas; Brickman, Adam M.; McDade, Eric; Ringman, John M.; Thompson, Paul M.; Saykin, Andrew J.; Ghetti, Bernardino; Sperling, Reisa A.; Johnson, Keith A.; Salloway, Stephen P.; Schofield, Peter R.; Masters, Colin L.; Villemagne, Victor L.; Fox, Nick C.; Förster, Stefan; Chen, Kewei; Reiman, Eric M.; Xiong, Chengjie; Marcus, Daniel S.; Weiner, Michael W.; Morris, John C.; Bateman, Randall J.; Benzinger, Tammie L. S.

2016-01-01

Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer’s Network (DIAN), an autosomal dominant Alzheimer’s disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer’s disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted. PMID:27010959

Estimation of salient regions related to chronic gastritis using gastric X-ray images.

Science.gov (United States)

Togo, Ren; Ishihara, Kenta; Ogawa, Takahiro; Haseyama, Miki

2016-10-01

Since technical knowledge and a high degree of experience are necessary for diagnosis of chronic gastritis, computer-aided diagnosis (CAD) systems that analyze gastric X-ray images are desirable in the field of medicine. Therefore, a new method that estimates salient regions related to chronic gastritis/non-gastritis for supporting diagnosis is presented in this paper. In order to estimate salient regions related to chronic gastritis/non-gastritis, the proposed method monitors the distance between a target image feature and Support Vector Machine (SVM)-based hyperplane for its classification. Furthermore, our method realizes removal of the influence of regions outside the stomach by using positional relationships between the stomach and other organs. Consequently, since the proposed method successfully estimates salient regions of gastric X-ray images for which chronic gastritis and non-gastritis are unknown, visual support for inexperienced clinicians becomes feasible. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mapping Winter Wheat with Multi-Temporal SAR and Optical Images in an Urban Agricultural Region.

Science.gov (United States)

Zhou, Tao; Pan, Jianjun; Zhang, Peiyu; Wei, Shanbao; Han, Tao

2017-05-25

Winter wheat is the second largest food crop in China. It is important to obtain reliable winter wheat acreage to guarantee the food security for the most populous country in the world. This paper focuses on assessing the feasibility of in-season winter wheat mapping and investigating potential classification improvement by using SAR (Synthetic Aperture Radar) images, optical images, and the integration of both types of data in urban agricultural regions with complex planting structures in Southern China. Both SAR (Sentinel-1A) and optical (Landsat-8) data were acquired, and classification using different combinations of Sentinel-1A-derived information and optical images was performed using a support vector machine (SVM) and a random forest (RF) method. The interference coherence and texture images were obtained and used to assess the effect of adding them to the backscatter intensity images on the classification accuracy. The results showed that the use of four Sentinel-1A images acquired before the jointing period of winter wheat can provide satisfactory winter wheat classification accuracy, with an F1 measure of 87.89%. The combination of SAR and optical images for winter wheat mapping achieved the best F1 measure-up to 98.06%. The SVM was superior to RF in terms of the overall accuracy and the kappa coefficient, and was faster than RF, while the RF classifier was slightly better than SVM in terms of the F1 measure. In addition, the classification accuracy can be effectively improved by adding the texture and coherence images to the backscatter intensity data.

Space Radar Image of Manaus region of Brazil

Science.gov (United States)

1994-01-01

These L-band images of the Manaus region of Brazil were acquired by the Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space shuttle Endeavour. The left image was acquired on April 12, 1994, and the middle image was acquired on October 3, 1994. The area shown is approximately 8 kilometers by 40 kilometers (5 miles by 25 miles). The two large rivers in this image, the Rio Negro (top) and the Rio Solimoes (bottom), combine at Manaus (west of the image) to form the Amazon River. The image is centered at about 3 degrees south latitude and 61 degrees west longitude. North is toward the top left of the images. The differences in brightness between the images reflect changes in the scattering of the radar channel. In this case, the changes are indicative of flooding. A flooded forest has a higher backscatter at L-band (horizontally transmitted and received) than an unflooded river. The extent of the flooding is much greater in the April image than in the October image, and corresponds to the annual, 10-meter (33-foot) rise and fall of the Amazon River. A third image at right shows the change in the April and October images and was created by determining which areas had significant decreases in the intensity of radar returns. These areas, which appear blue on the third image at right, show the dramatic decrease in the extent of flooded forest, as the level of the Amazon River falls. The flooded forest is a vital habitat for fish and floating meadows are an important source of atmospheric methane. This demonstrates the capability of SIR-C/X-SAR to study important environmental changes that are impossible to see with optical sensors over regions such as the Amazon, where frequent cloud cover and dense forest canopies obscure monitoring of floods. Field studies by boat, on foot and in low-flying aircraft by the University of California at Santa Barbara, in collaboration with Brazil's Instituto Nacional de Pesguisas Estaciais, during

Diffusion tensor imaging tensor shape analysis for assessment of regional white matter differences.

Science.gov (United States)

Middleton, Dana M; Li, Jonathan Y; Lee, Hui J; Chen, Steven; Dickson, Patricia I; Ellinwood, N Matthew; White, Leonard E; Provenzale, James M

2017-08-01

Purpose The purpose of this study was to investigate a novel tensor shape plot analysis technique of diffusion tensor imaging data as a means to assess microstructural differences in brain tissue. We hypothesized that this technique could distinguish white matter regions with different microstructural compositions. Methods Three normal canines were euthanized at seven weeks old. Their brains were imaged using identical diffusion tensor imaging protocols on a 7T small-animal magnetic resonance imaging system. We examined two white matter regions, the internal capsule and the centrum semiovale, each subdivided into an anterior and posterior region. We placed 100 regions of interest in each of the four brain regions. Eigenvalues for each region of interest triangulated onto tensor shape plots as the weighted average of three shape metrics at the plot's vertices: CS, CL, and CP. Results The distribution of data on the plots for the internal capsule differed markedly from the centrum semiovale data, thus confirming our hypothesis. Furthermore, data for the internal capsule were distributed in a relatively tight cluster, possibly reflecting the compact and parallel nature of its fibers, while data for the centrum semiovale were more widely distributed, consistent with the less compact and often crossing pattern of its fibers. This indicates that the tensor shape plot technique can depict data in similar regions as being alike. Conclusion Tensor shape plots successfully depicted differences in tissue microstructure and reflected the microstructure of individual brain regions. This proof of principle study suggests that if our findings are reproduced in larger samples, including abnormal white matter states, the technique may be useful in assessment of white matter diseases.

Ex-PRESS glaucoma filter: an MRI compatible metallic orbital foreign body imaged at 1.5 and 3T.

Science.gov (United States)

Mabray, M C; Uzelac, A; Talbott, J F; Lin, S C; Gean, A D

2015-05-01

To report on the MRI compatibility of the Ex-PRESS glaucoma filtration device, a tiny metallic implant placed into the anterior chamber of the eye that is much smaller than traditional glaucoma shunts, and to educate the radiology community regarding its appearance. Seven patients with Ex-PRESS glaucoma filtration devices were identified that had undergone MRI at San Francisco General Hospital/University of California San Francisco Medical Center by searching and cross-referencing the radiology reporting system and the electronic medical record. MRI images were reviewed for artefact interfering with interpretation. Ophthalmology examinations were reviewed for evidence of complications. Eighteen individual MRI examinations were performed during 12 unique MRI events on these 7 patients. 13/18 individual MRI examinations and 7/12 MRI events were performed at 3 T with the others performed at 1.5 T. Mean time from Ex-PRESS implantation to MRI was 17.5 months. Mean time from MRI to first ophthalmology examination was 1.1 months and from MRI to latest ophthalmology examination was 6.6 months. Susceptibility artefact did not interfere with image interpretation and no complications related to MRI were encountered. The Ex-PRESS glaucoma filtration device appears to be safe for MRI at 1.5 and 3 T and does not produce significant susceptibility artefact to affect diagnostic interpretation adversely. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Assessment of regional lung functional impairment with co-registered respiratory-gated ventilation/perfusion SPET-CT images: initial experiences

International Nuclear Information System (INIS)

Suga, Kazuyoshi; Yasuhiko, Kawakami; Zaki, Mohammed; Yamashita, Tomio; Seto, Aska; Matsumoto, Tsuneo; Matsunaga, Naofumi

2004-01-01

In this study, respiratory-gated ventilation and perfusion single-photon emission tomography (SPET) were used to define regional functional impairment and to obtain reliable co-registration with computed tomography (CT) images in various lung diseases. Using a triple-headed SPET unit and a physiological synchroniser, gated perfusion SPET was performed in a total of 78 patients with different pulmonary diseases, including metastatic nodules (n=15); in 34 of these patients, it was performed in combination with gated technetium-99m Technegas SPET. Projection data were acquired using 60 stops over 120 for each detector. Gated end-inspiration and ungated images were reconstructed from 1/8 data centered at peak inspiration for each regular respiratory cycle and full respiratory cycle data, respectively. Gated images were registered with tidal inspiration CT images using automated three-dimensional (3D) registration software. Registration mismatch was assessed by measuring 3D distance of the centroid of the nine selected round perfusion-defective nodules. Gated SPET images were completed within 29 min, and increased the number of visible ventilation and perfusion defects by 9.7% and 17.2%, respectively, as compared with ungated images; furthermore, lesion-to-normal lung contrast was significantly higher on gated SPET images. In the nine round perfusion-defective nodules, gated images yielded a significantly better SPET-CT match compared with ungated images (4.9±3.1 mm vs 19.0±9.1 mm, P<0.001). The co-registered SPET-CT images allowed accurate perception of the location and extent of each ventilation/perfusion defect on the underlying CT anatomy, and characterised the pathophysiology of the various diseases. By reducing respiratory motion effects and enhancing perfusion/ventilation defect clarity, gated SPET can provide reliable co-registered images with CT images to accurately characterise regional functional impairment in various lung diseases. (orig.)

Relationships between Classroom Schedule Types and Performance on the Algebra I Criterion-Referenced Test

Science.gov (United States)

Murray, Gregory V.; Moyer-Packenham, Patricia S.

2014-01-01

One option for length of individual mathematics class periods is the schedule type selected for Algebra I classes. This study examined the relationship between student achievement, as indicated by Algebra I Criterion-Referenced Test scores, and the schedule type for Algebra I classes. Data obtained from the Utah State Office of Education included…

Spirometrically gated /sup 133/Xe ventilation imaging and phase analysis for assessment of regional lung function

Energy Technology Data Exchange (ETDEWEB)

Inoue, Tomio (Kanto Teishin Hospital, Tokyo (Japan))

1984-10-01

The purpose of this study is to develop the technique of performing spirometrically gated /sup 133/Xe ventilation imaging and to evaluate its clinical usefulness for the assessment of regional ventilatory function in various lung diseases. Patients rebreathed /sup 133/Xe gas through the system with constant rates signaled by a metronome. The trigger signals from the patients were recorded in a minicomputer for 60 respiratory cycles simultaneously with posterior lung images. Functional images (phase analysis images) indicating phase and amplitude of regional ventilation were constructed by the first harmonic Fourier analysis. Materials included 13 normal volunteers and patients with COPD (24), lung cancer (5), pulmonary embolism (4) and others (20). In normal controls, phase analysis images before respiratory motion correction revealed gradual decrease in amplitude from base to apex with uniform phase distribution. The amplitude and phase distribution after respiratory motion correction became even more uniform. In patients with COPD, phase analysis images showed asymmetrical and irregular amplitude distribution with non-uniform phase distribution. The standard deviation (S.D.) of phase histogram correlated well with FEVsub(1.0)% (r=0.71, p < 0.001) and down slope of flow-volume curve (r=0.55, p < 0.001), and less prominently with %VC (r=0.42, p < 0.01). Mean S.D. in patients with COPD (12.3 +- 6.5 degree, mean+-1 s.d.) was significantly larger than in normal controls (6.3 +- 1.5). Amplitude profile curve analysis revealed 83% sensitivity for the detection of abnormal spirometric respiratory function test. Data aquisition and processing of present method are rapid and easy to perform. The phase analysis of the gated ventilation images should prove useful in the clinical evaluation of patients with uneven ventilation such as COPD.

Comparison of MR imaging after administration of dysprosium-based magnetic-susceptibility contrast media with diffusion-weighted MR imaging in evaluation of regional cerebral ischemia

International Nuclear Information System (INIS)

Moseley, M.E.; Kucharczyk, J.; Kurhanewicz, J.; Mintorovitch, J.; Cohen, Y.; Rocklage, S.; Quay, S.C.; Norman, D.

1989-01-01

This paper reports on a study to establish whether a nonionic T2-shortening contrast agent, Dy-DTPA-bis(methylamide) (Dy-DTPA-BMA), would facilitate early detection of stroke-induced cerebral perfusion deficits. The sensitivity of susceptibility-enhanced MR imaging was compared with that of diffusion-weighted MR imaging in the same cats subjected to unilateral occlusion of the middle cerebral artery (MCA). A 2-T unit, equipped with self-shielded gradient coils (± 20 G/cm, 15-cm bore size), was used in conjunction with an 8.5-cm inner diameter low-pass bird cage proton imaging coil. Diffusion-weighted images displayed increased signal intensity in the ischemic MCA territory less than 1 hour after occlusion, whereas T2-weighted MR images without contrast enhancement usually failed to depict injury for 2--3 hours after toke. With contrast administration (0.5 mmoles/kg of Dy-DTPA-BMA), however, T2-weighted images revealed perfusion deficits (hyperintensity) within 1 hour after MCA occlusion, and these corresponded to the anatomic regions of ischemic injury shown on diffusion-weighted MR images

Clinical stage T1c prostate cancer: evaluation with endorectal MR imaging and MR spectroscopic imaging.

Science.gov (United States)

Zhang, Jingbo; Hricak, Hedvig; Shukla-Dave, Amita; Akin, Oguz; Ishill, Nicole M; Carlino, Lauren J; Reuter, Victor E; Eastham, James A

2009-11-01

To assess the diagnostic accuracy of endorectal magnetic resonance (MR) imaging and MR spectroscopic imaging for prediction of the pathologic stage of prostate cancer and the presence of clinically nonimportant disease in patients with clinical stage T1c prostate cancer. The institutional review board approved-and waived the informed patient consent requirement for-this HIPAA-compliant study involving 158 patients (median age, 58 years; age range, 40-76 years) who had clinical stage T1c prostate cancer, had not been treated preoperatively, and underwent combined 1.5-T endorectal MR imaging-MR spectroscopic imaging between January 2003 and March 2004 before undergoing radical prostatectomy. On the MR images and combined endorectal MR-MR spectroscopic images, two radiologists retrospectively and independently rated the likelihood of cancer in 12 prostate regions and the likelihoods of extracapsular extension (ECE), seminal vesicle invasion (SVI), and adjacent organ invasion by using a five-point scale, and they determined the probability of clinically nonimportant prostate cancer by using a four-point scale. Whole-mount step-section pathology maps were used for imaging-pathologic analysis correlation. Receiver operating characteristic curves were constructed and areas under the curves (AUCs) were estimated nonparametrically for assessment of reader accuracy. At surgical-pathologic analysis, one (0.6%) patient had no cancer; 124 (78%) patients, organ-confined (stage pT2) disease; 29 (18%) patients, ECE (stage pT3a); two (1%) patients, SVI (stage pT3b); and two (1%) patients, bladder neck invasion (stage pT4). Forty-six (29%) patients had a total tumor volume of less than 0.5 cm(3). With combined MR imaging-MR spectroscopic imaging, the two readers achieved 80% accuracy in disease staging and AUCs of 0.62 and 0.71 for the prediction of clinically nonimportant cancer. Clinical stage T1c prostate cancers are heterogeneous in pathologic stage and volume. MR imaging may

A self-referencing biosensor for real-time monitoring of physiological ATP transport in plant systems.

Science.gov (United States)

Vanegas, Diana C; Clark, Greg; Cannon, Ashley E; Roux, Stanley; Chaturvedi, Prachee; McLamore, Eric S

2015-12-15

The objective of this study was to develop a self-referencing electrochemical biosensor for the direct measurement of ATP flux into the extracellular matrix by living cells/organisms. The working mechanism of the developed biosensor is based on the activity of glycerol kinase and glycerol-3-phosphate oxidase. A stratified bi-enzyme nanocomposite was created using a protein-templated silica sol gel encapsulation technique on top of graphene-modified platinum electrodes. The biosensor exhibited excellent electrochemical performance with a sensitivity of 2.4±1.8 nA/µM, a response time of 20±13 s and a lower detection limit of 1.3±0.7 nM. The self-referencing biosensor was used to measure exogenous ATP efflux by (i) germinating Ceratopteris spores and (ii) growing Zea mays L. roots. This manuscript demonstrates the first development of a non-invasive ATP micro-biosensor for the direct measurement of eATP transport in living tissues. Before this work, assays of eATP have not been able to record the temporally transient movement of ATP at physiological levels (nM and sub-nM). The method demonstrated here accurately measured [eATP] flux in the immediate vicinity of plant cells. Although these proof of concept experiments focus on plant tissues, the technique developed herein is applicable to any living tissue, where nanomolar concentrations of ATP play a critical role in signaling and development. This tool will be invaluable for conducting hypothesis-driven life science research aimed at understanding the role of ATP in the extracellular environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Automatic segmentation of MRI head images by 3-D region growing method which utilizes edge information

International Nuclear Information System (INIS)

Jiang, Hao; Suzuki, Hidetomo; Toriwaki, Jun-ichiro

1991-01-01

This paper presents a 3-D segmentation method that automatically extracts soft tissue from multi-sliced MRI head images. MRI produces a sequence of two-dimensional (2-D) images which contains three-dimensional (3-D) information of organs. To utilize such information we need effective algorithms to treat 3-D digital images and to extract organs and tissues of interest. We developed a method to extract the brain from MRI images which uses a region growing procedure and integrates information of uniformity of gray levels and information of the presence of edge segments in the local area around the pixel of interest. First we generate a kernel region which is a part of brain tissue by simple thresholding. Then we grow the region by means of a region growing algorithm under the control of 3-D edge existence to obtain the region of the brain. Our method is rather simple because it uses basic 3-D image processing techniques like spatial difference. It is robust for variation of gray levels inside a tissue since it also refers to the edge information in the process of region growing. Therefore, the method is flexible enough to be applicable to the segmentation of other images including soft tissues which have complicated shapes and fluctuation in gray levels. (author)

Regional quantitative analysis of cortical surface maps of FDG PET images

CERN Document Server

Protas, H D; Hayashi, K M; Chin Lung, Yu; Bergsneider, M; Sung Cheng, Huang

2006-01-01

Cortical surface maps are advantageous for visualizing the 3D profile of cortical gray matter development and atrophy, and for integrating structural and functional images. In addition, cortical surface maps for PET data, when analyzed in conjunction with structural MRI data allow us to investigate, and correct for, partial volume effects. Here we compared quantitative regional PET values based on a 3D cortical surface modeling approach with values obtained directly from the 3D FDG PET images in various atlas-defined regions of interest (ROIs; temporal, parietal, frontal, and occipital lobes). FDG PET and 3D MR (SPGR) images were obtained and aligned to ICBM space for 15 normal subjects. Each image was further elastically warped in 2D parameter space of the cortical surface, to align major cortical sulci. For each point within a 15 mm distance of the cortex, the value of the PET intensity was averaged to give a cortical surface map of FDG uptake. The average PET values on the cortical surface map were calcula...

Lateral and medial ventral occipitotemporal regions interact during the recognition of images revealed from noise

Directory of Open Access Journals (Sweden)

Barbara eNordhjem

2016-01-01

Full Text Available Several studies suggest different functional roles for the medial and the lateral ventral sections in object recognition. Texture and surface information is processed in medial regions, while shape information is processed in lateral sections. This begs the question whether and how these functionally specialized sections interact with each other and with early visual cortex to facilitate object recognition. In the current research, we set out to answer this question. In an fMRI study, thirteen subjects viewed and recognized images of objects and animals that were gradually revealed from noise while their brains were being scanned. We applied dynamic causal modeling (DCM – a method to characterize network interactions – to determine the modulatory effect of object recognition on a network comprising the primary visual cortex (V1, the lingual gyrus (LG in medial ventral cortex and the lateral occipital cortex (LO. We found that object recognition modulated the bilateral connectivity between LG and LO. Moreover, the feed-forward connectivity from V1 to LG and LO was modulated, while there was no evidence for feedback from these regions to V1 during object recognition. In particular, the interaction between medial and lateral areas supports a framework in which visual recognition of objects is achieved by networked regions that integrate information on image statistics, scene content and shape – rather than by a single categorically specialized region – within the ventral visual cortex.

Next Generation Parallelization Systems for Processing and Control of PDS Image Node Assets

Science.gov (United States)

Verma, R.

2017-06-01

We present next-generation parallelization tools to help Planetary Data System (PDS) Imaging Node (IMG) better monitor, process, and control changes to nearly 650 million file assets and over a dozen machines on which they are referenced or stored.

Development of a system for transferring images via a network: supporting a regional liaison.

Science.gov (United States)

Mihara, Naoki; Manabe, Shiro; Takeda, Toshihiro; Shinichirou, Kitamura; Junichi, Murakami; Kouji, Kiso; Matsumura, Yasushi

2013-01-01

We developed a system that transfers images via network and started using them in our hospital's PACS (Picture Archiving and Communication Systems) in 2006. We are pleased to report that the system has been re-developed and has been running so that there will be a regional liaison in the future. It has become possible to automatically transfer images simply by selecting the destination hospital that is registered in advance at the relay server. The gateway of this system can send images to a multi-center, relay management server, which receives the images and resends them. This system has the potential to be useful for image exchange, and to serve as a regional medical liaison.

Automated Region of Interest Retrieval of Metallographic Images for Quality Classification in Industry

Directory of Open Access Journals (Sweden)

Petr Kotas

2012-01-01

Full Text Available The aim of the research is development and testing of new methods to classify the quality of metallographic samples of steels with high added value (for example grades X70 according API. In this paper, we address the development of methods to classify the quality of slab samples images with the main emphasis on the quality of the image center called as segregation area. For this reason, we introduce an alternative method for automated retrieval of region of interest. In the first step, the metallographic image is segmented using both spectral method and thresholding. Then, the extracted macrostructure of the metallographic image is automatically analyzed by statistical methods. Finally, automatically extracted region of interests are compared with results of human experts.  Practical experience with retrieval of non-homogeneous noised digital images in industrial environment is discussed as well.

Imaging regional variation of cellular proliferation in gliomas using 3'-deoxy-3'-[18F]fluorothymidine positron-emission tomography: an image-guided biopsy study

International Nuclear Information System (INIS)

Price, S.J.; Fryer, T.D.; Cleij, M.C.; Dean, A.F.; Joseph, J.; Salvador, R.; Wang, D.D.; Hutchinson, P.J.; Clark, J.C.; Burnet, N.G.; Pickard, J.D.; Aigbirhio, F.I.

2009-01-01

Aim: To compare regional variations in uptake of 3'-deoxy-3'- [ 18 F]-fluorothymidine (FLT) images using positron-emission tomography (PET) with measures of cellular proliferation from biopsy specimens obtained by image-guided brain biopsies. Materials and methods: Fourteen patients with a supratentorial glioma that required an image-guided brain biopsy were imaged preoperatively with dynamic PET after the administration of FLT. Maps of FLT irreversible uptake rate (K i ) and standardized uptake value (SUV) were calculated. These maps were co-registered to a gadolinium-enhanced T1-weighted spoiled gradient echo (SPGR) sequence that was used for biopsy guidance, and the mean and maximum K i and SUV determined for each biopsy site. These values were correlated with the MIB-1 labelling index (a tissue marker of proliferation) from these biopsy sites. Results: A total of 57 biopsy sites were studied. Although all measures correlated with MIB-1 labelling index, K i max provided the best correlation (Pearson coefficient, r = 0.68; p i mean (±SD) was significantly higher than in normal tissue (3.3 ± 1.7 x 10 -3 ml plasma /min/ml tissue versus 1.2 ± 0.7 x 10 -3 ml plasma /min/ml tissue ; p = 0.001). High-grade gliomas showed heterogeneous uptake with a mean K i of 7.7 ± 4 x 10 -3 ml plasma /min/ml tissue . A threshold K i mean of 1.8 x 10 -3 differentiates between normal tissue and tumour (sensitivity 84%, specificity 88%); however, the latter threshold underestimated the extent of tumour in half the cases. SUV closely agreed with K i measurements. Conclusion: FLT PET is a useful marker of cellular proliferation that correlates with regional variation in cellular proliferation; however, it is unable to identify the margin of gliomas

Adaptive polarization image fusion based on regional energy dynamic weighted average

Institute of Scientific and Technical Information of China (English)

ZHAO Yong-qiang; PAN Quan; ZHANG Hong-cai

2005-01-01

According to the principle of polarization imaging and the relation between Stokes parameters and the degree of linear polarization, there are much redundant and complementary information in polarized images. Since man-made objects and natural objects can be easily distinguished in images of degree of linear polarization and images of Stokes parameters contain rich detailed information of the scene, the clutters in the images can be removed efficiently while the detailed information can be maintained by combining these images. An algorithm of adaptive polarization image fusion based on regional energy dynamic weighted average is proposed in this paper to combine these images. Through an experiment and simulations,most clutters are removed by this algorithm. The fusion method is used for different light conditions in simulation, and the influence of lighting conditions on the fusion results is analyzed.

The study of brain dopamine transporter 99Tcm-TRODAT-1 SPECT imaging

International Nuclear Information System (INIS)

Yang Jian; Su Min; Liu Xiuqian; Liang Weijuan; Zhao Bin; Xu Zhien

2006-01-01

Objective: To investigate the distribution character of 99 Tc m -2β-[N, N'-bis (2-mercaptoethyl) ethylenediamino] methyl, 3β-(4-chlorophenyl) tropane (TRODAT-1) in basal ganglia and the diagnostic value of SPECT imaging in Parkinson' s disease (PD). Methods: 99 Tc m -TRODAT-l SPECT imaging was performed in 30 PD patients and 16 age-matched healthy volunteers. Two semiquantitative analysis methods were used: (1)Striatum(ST)/cerebellum (CB) uptake ratio (ST/CB) was calculated by regions of interest (ROIs) in three transverse and sagittal slice. (2) ROIs were drawn manually on six subregions of both basal ganglia and also CB and occipital region(OC) as reference, and the corresponding uptake ratio of ROI/(OC + CB/2) was calculated. Results: The ST/CB in transverse and sagittal slice for the left and right were 1.55 ± 0.15, 1.58 ± 0.14 and 1.62 ± 0.17, 1.69 ± 0.16 respectively in healthy volunteers. The ST/CB and ROI/(OC + CB/2) in the basal ganglia of PD patients were significantly less than those of healthy volunteers (P 99 Tc m -TRODAT-1 SPECT imaging is an effective method in diagnosis of PD. (authors)

Influence of Electrotactile Tongue Feedback on Controlling Upright Stance during Rotational and/or Translational Sway-referencing with Galvanic Vestibular Stimulation

Science.gov (United States)

Wood, Scott J.; Tyler, Mitchell E.; Bach-y-Rita, Paul; MacDougall, Hamish G.; Moore, Steven T.; Stallings, Valerie L.; Paloski, William H.; Black, F. Owen

2007-01-01

Integration of multi-sensory inputs to detect tilts relative to gravity is critical for sensorimotor control of upright orientation. Displaying body orientation using electrotactile feedback to the tongue has been developed by Bach-y-Rita and colleagues as a sensory aid to maintain upright stance with impaired vestibular feedback. MacDougall et al. (2006) recently demonstrated that unpredictably varying Galvanic vestibular stimulation (GVS) significantly increased anterior-posterior (AP) sway during rotational sway referencing with eyes closed. The purpose of this study was to assess the influence of electrotactile feedback on postural control performance with pseudorandom binaural bipolar GVS. Postural equilibrium was measured with a computerized hydraulic platform in 10 healthy adults (6M, 4F, 24-65 y). Tactile feedback (TF) of pitch and roll body orientation was derived from a two-axis linear accelerometer mounted on a torso belt and displayed on a 144-point electrotactile array held against the anterior dorsal tongue (BrainPort, Wicab, Inc., Middleton, WI). Subjects were trained to use TF by voluntarily swaying to draw figures on their tongue, both with and without GVS. Subjects were required to keep the intraoral display in their mouths on all trials, including those that did not provide TF. Subjects performed 24 randomized trials (20 s duration with eyes closed) including four support surface conditions (fixed, rotational sway-referenced, translating the support surface proportional to AP sway, and combined rotational-translational sway-referencing), each repeated twice with and without GVS, and with combined GVS and TF. Postural performance was assessed using deviations from upright (peak-to-peak and RMS sway) and convergence toward stability limits (time and distance to base of support boundaries). Postural stability was impaired with GVS in all platform conditions, with larger decrements in performance during trials with rotation sway-referencing

Automated extraction of metastatic liver cancer regions from abdominal contrast CT images

International Nuclear Information System (INIS)

Yamakawa, Junki; Matsubara, Hiroaki; Kimura, Shouta; Hasegawa, Junichi; Shinozaki, Kenji; Nawano, Shigeru

2010-01-01

In this paper, automated extraction of metastatic liver cancer regions from abdominal contrast X-ray CT images is investigated. Because even in Japan, cases of metastatic liver cancers are increased due to recent Europeanization and/or Americanization of Japanese eating habits, development of a system for computer aided diagnosis of them is strongly expected. Our automated extraction procedure consists of following four steps; liver region extraction, density transformation for enhancement of cancer regions, segmentation for obtaining candidate cancer regions, and reduction of false positives by shape feature. Parameter values used in each step of the procedure are decided based on density and shape features of typical metastatic liver cancers. In experiments using practical 20 cases of metastatic liver tumors, it is shown that 56% of true cancers can be detected successfully from CT images by the proposed procedure. (author)

A model-referenced procedure to support adversarial decision processes

International Nuclear Information System (INIS)

Bunn, D.W.; Vlahos, K.

1992-01-01

In public enquiries concerning major facilities, such as the construction of a new electric power plant, it is observed that a useable decision model should be made commonly available alongside the open provision of data and assumptions. The protagonist, eg the electric utility, generally makes use of a complex, proprietary model for detailed evaluation of options. A simple emulator of this, based upon a regression analysis of numerous scenarios, and validated by further simulations is shown to be feasible and potentially attractive. It would be in the interests of the utility to make such a model-referenced decision support method generally available. The approach is considered in relation to the recent Hinkley Point C public enquiry for a new nuclear power plant in the UK. (Author)

A Local Region of Interest Imaging Method for Electrical Impedance Tomography with Internal Electrodes

Directory of Open Access Journals (Sweden)

Hyeuknam Kwon

2013-01-01

Full Text Available Electrical Impedance Tomography (EIT is a very attractive functional imaging method despite the low sensitivity and resolution. The use of internal electrodes with the conventional reconstruction algorithms was not enough to enhance image resolution and accuracy in the region of interest (ROI. We propose a local ROI imaging method with internal electrodes developed from careful analysis of the sensitivity matrix that is designed to reduce the sensitivity of the voxels outside the local region and optimize the sensitivity of the voxel inside the local region. We perform numerical simulations and physical measurements to demonstrate the localized EIT imaging method. In preliminary results with multiple objects we show the benefits of using an internal electrode and the improved resolution due to the local ROI image reconstruction method. The sensitivity is further increased by allowing the surface electrodes to be unevenly spaced with a higher density of surface electrodes near the ROI. Also, we analyse how much the image quality is improved using several performance parameters for comparison. While these have not yet been studied in depth, it convincingly shows an improvement in local sensitivity in images obtained with an internal electrode in comparison to a standard reconstruction method.

Imaging and detection of early stage dental caries with an all-optical photoacoustic microscope

Science.gov (United States)

Hughes, D. A.; Sampathkumar, A.; Longbottom, C.; Kirk, K. J.

2015-01-01

Tooth decay, at its earliest stages, manifests itself as small, white, subsurface lesions in the enamel. Current methods for detection in the dental clinic are visual and tactile investigations, and bite-wing X-ray radiographs. These techniques suffer from poor sensitivity and specificity at the earliest (and reversible) stages of the disease due to the small size (tooth decay. Ex-vivo tooth samples exhibiting white spot lesions were scanned and were found to generate a larger (one order of magnitude) photoacoustic (PA) signal in the lesion regions compared to healthy enamel. The high contrast in the PA images potentially allows lesions to be imaged and measured at a much earlier stage than current clinical techniques allow. PA images were cross referenced with histology photographs to validate our experimental results. Our PA system provides a noncontact method for early detection of white-spot lesions with a high detection bandwidth that offers advantages over previously demonstrated ultrasound methods. The technique provides the sensing depth of an ultrasound system, but with the spatial resolution of an optical system.

A Novel Segmentation Approach Combining Region- and Edge-Based Information for Ultrasound Images

Directory of Open Access Journals (Sweden)

Yaozhong Luo

2017-01-01

Full Text Available Ultrasound imaging has become one of the most popular medical imaging modalities with numerous diagnostic applications. However, ultrasound (US image segmentation, which is the essential process for further analysis, is a challenging task due to the poor image quality. In this paper, we propose a new segmentation scheme to combine both region- and edge-based information into the robust graph-based (RGB segmentation method. The only interaction required is to select two diagonal points to determine a region of interest (ROI on the original image. The ROI image is smoothed by a bilateral filter and then contrast-enhanced by histogram equalization. Then, the enhanced image is filtered by pyramid mean shift to improve homogeneity. With the optimization of particle swarm optimization (PSO algorithm, the RGB segmentation method is performed to segment the filtered image. The segmentation results of our method have been compared with the corresponding results obtained by three existing approaches, and four metrics have been used to measure the segmentation performance. The experimental results show that the method achieves the best overall performance and gets the lowest ARE (10.77%, the second highest TPVF (85.34%, and the second lowest FPVF (4.48%.

Automatic detection of the hippocampal region associated with Alzheimer's disease from microscopic images of mice brain

Science.gov (United States)

Albaidhani, Tahseen; Hawkes, Cheryl; Jassim, Sabah; Al-Assam, Hisham

2016-05-01

The hippocampus is the region of the brain that is primarily associated with memory and spatial navigation. It is one of the first brain regions to be damaged when a person suffers from Alzheimer's disease. Recent research in this field has focussed on the assessment of damage to different blood vessels within the hippocampal region from a high throughput brain microscopic images. The ultimate aim of our research is the creation of an automatic system to count and classify different blood vessels such as capillaries, veins, and arteries in the hippocampus region. This work should provide biologists with efficient and accurate tools in their investigation of the causes of Alzheimer's disease. Locating the boundary of the Region of Interest in the hippocampus from microscopic images of mice brain is the first essential stage towards developing such a system. This task benefits from the variation in colour channels and texture between the two sides of the hippocampus and the boundary region. Accordingly, the developed initial step of our research to locating the hippocampus edge uses a colour-based segmentation of the brain image followed by Hough transforms on the colour channel that isolate the hippocampus region. The output is then used to split the brain image into two sides of the detected section of the boundary: the inside region and the outside region. Experimental results on a sufficiently number of microscopic images demonstrate the effectiveness of the developed solution.

Redefining the Practice of Peer Review Through Intelligent Automation Part 1: Creation of a Standardized Methodology and Referenceable Database.

Science.gov (United States)

Reiner, Bruce I

2017-10-01

Conventional peer review practice is compromised by a number of well-documented biases, which in turn limit standard of care analysis, which is fundamental to determination of medical malpractice. In addition to these intrinsic biases, other existing deficiencies exist in current peer review including the lack of standardization, objectivity, retrospective practice, and automation. An alternative model to address these deficiencies would be one which is completely blinded to the peer reviewer, requires independent reporting from both parties, utilizes automated data mining techniques for neutral and objective report analysis, and provides data reconciliation for resolution of finding-specific report differences. If properly implemented, this peer review model could result in creation of a standardized referenceable peer review database which could further assist in customizable education, technology refinement, and implementation of real-time context and user-specific decision support.

Receiver function images of the central Chugoku region in the Japanese islands using Hi-net data

Science.gov (United States)

Ramesh, D. S.; Wakatsu, H. K.; Watada, S.; Yuan, X.

2005-04-01

Crustal configuration of the central Chugoku region with disposition of the Philippine Sea Plate (PHS) in this area are investigated through the receiver function approach using short-period Hi-net data. Images of the upper mantle discontinuities are also obtained. Restituted short-period receiver functions bring out discernible variations in average composition of the crust and its thickness in the study region. The Vp/ Vs values in the study area are generally high, reaching values in excess of 1.85 at a few places. The central part of the study region showing the highest Vp/ Vs values is coincidentally a subregion of least seismicity, possibly bestowed with special subsurface structure. Migrated receiver function images, both Ps and Pps images, unambiguously trace the NW subducting PHS taking a steeper plunge in the northwest part of the Chugoku region reaching depths of 70 km from its low dip disposition in the southeast. An excellent correlation of the subducting PHS with the hypocenters is also seen. We demonstrate that short-period data after restitution and application of appropriate low pass filters can indeed detect presence of the global 410-km and 660-km discontinuities and map their disposition reasonably well. Our migrated receiver functions image the deflections in the 410-km and 660-km discontinuities in an anti-correlated fashion on expected lines of Clapeyron slope predictions induced by subduction of the Pacific plate (PAC) beneath Japanese islands, though PAC itself is feebly traced but shows good correlation with slab seismicity.

First analysis of solar structures in 1.21 mm full-disc ALMA image of the Sun

Science.gov (United States)

Brajša, R.; Sudar, D.; Benz, A. O.; Skokić, I.; Bárta, M.; Pontieu, B. De; Kim, S.; Kobelski, A.; Kuhar, M.; Shimojo, M.; Wedemeyer, S.; White, S.; Yagoubov, P.; Yan, Y.

2018-05-01

Context. Various solar features can be seen in emission or absorption on maps of the Sun in the millimetre and submillimetre wavelength range. The recently installed Atacama Large Millimetre/submillimetre Array (ALMA) is capable of observing the Sun in that wavelength range with an unprecedented spatial, temporal and spectral resolution. To interpret solar observations with ALMA, the first important step is to compare solar ALMA maps with simultaneous images of the Sun recorded in other spectral ranges. Aims: The first aim of the present work is to identify different structures in the solar atmosphere seen in the optical, infrared, and EUV parts of the spectrum (quiet Sun, active regions, prominences on the disc, magnetic inversion lines, coronal holes and coronal bright points) in a full-disc solar ALMA image. The second aim is to measure the intensities (brightness temperatures) of those structures and to compare them with the corresponding quiet Sun level. Methods: A full-disc solar image at 1.21 mm obtained on December 18, 2015, during a CSV-EOC campaign with ALMA is calibrated and compared with full-disc solar images from the same day in Hα line, in He I 1083 nm line core, and with various SDO images (AIA at 170 nm, 30.4 nm, 21.1 nm, 19.3 nm, and 17.1 nm and HMI magnetogram). The brightness temperatures of various structures are determined by averaging over corresponding regions of interest in the calibrated ALMA image. Results: Positions of the quiet Sun, active regions, prominences on the disc, magnetic inversion lines, coronal holes and coronal bright points are identified in the ALMA image. At the wavelength of 1.21 mm, active regions appear as bright areas (but sunspots are dark), while prominences on the disc and coronal holes are not discernible from the quiet Sun background, despite having slightly less intensity than surrounding quiet Sun regions. Magnetic inversion lines appear as large, elongated dark structures and coronal bright points correspond

Moment-ration imaging of seismic regions for earthquake prediction

Science.gov (United States)

Lomnitz, Cinna

1993-10-01

An algorithm for predicting large earthquakes is proposed. The reciprocal ratio (mri) of the residual seismic moment to the total moment release in a region is used for imaging seismic moment precursors. Peaks in mri predict recent major earthquakes, including the 1985 Michoacan, 1985 central Chile, and 1992 Eureka, California earthquakes.

Image and Substance Failures in Regional Organisations: Causes, Consequences, Learning and Change?

Directory of Open Access Journals (Sweden)

Meng Hsuan Chou

2016-08-01

Full Text Available States often pool their sovereignty, capacity and resources to provide regionally specific public goods, such as security or trade rules, and regional organisations play important roles in international relations as institutions that attempt to secure peace and contribute to achieving other similar global policy goals. We observe failures occurring in these arrangements and activities in two areas: substance and image. To analytically account for this, we distinguish four modes of substance and image change and link these to specific types of failure and (lack of learning. To empirically ground and test our assumptions, we examine instances of image failure in ASEAN (political/security policy and substantive policy failure in EU labour migration policy. In so doing, this article contributes to several different fields of study and concepts that have hitherto rarely engaged with one another: analyses of policy failure from public policy, and regional integration concerns from area studies and international relations. We conclude with suggestions for ways forward to further analyse and understand failures at the international and supranational levels.

Adaptive optics imaging of healthy and abnormal regions of retinal nerve fiber bundles of patients with glaucoma.

Science.gov (United States)

Chen, Monica F; Chui, Toco Y P; Alhadeff, Paula; Rosen, Richard B; Ritch, Robert; Dubra, Alfredo; Hood, Donald C

2015-01-08

To better understand the nature of glaucomatous damage of the macula, especially the structural changes seen between relatively healthy and clearly abnormal (AB) retinal regions, using an adaptive optics scanning light ophthalmoscope (AO-SLO). Adaptive optics SLO images and optical coherence tomography (OCT) vertical line scans were obtained on one eye of seven glaucoma patients, with relatively deep local arcuate defects on the 10-2 visual field test in one (six eyes) or both hemifields (one eye). Based on the OCT images, the retinal nerve fiber (RNF) layer was divided into two regions: (1) within normal limits (WNL), relative RNF layer thickness within mean control values ±2 SD; and (2) AB, relative thickness less than -2 SD value. As seen on AO-SLO, the pattern of AB RNF bundles near the border of the WNL and AB regions differed across eyes. There were normal-appearing bundles in the WNL region of all eyes and AB-appearing bundles near the border with the AB region. This region with AB bundles ranged in extent from a few bundles to the entire AB region in the case of one eye. All other eyes had a large AB region without bundles. However, in two of these eyes, a few bundles were seen within this region of otherwise missing bundles. The AO-SLO images revealed details of glaucomatous damage that are difficult, if not impossible, to see with current OCT technology. Adaptive optics SLO may prove useful in following progression in clinical trials, or in disease management, if AO-SLO becomes widely available and easy to use. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

Nanoparticle-based luminescent probes for intracellular sensing and imaging of pH.

Science.gov (United States)

Schäferling, Michael

2016-05-01

Fluorescence imaging microscopy is an essential tool in biomedical research. Meanwhile, various fluorescent probes are available for the staining of cells, cell membranes, and organelles. Though, to monitor intracellular processes and dysfunctions, probes that respond to ubiquitous chemical parameters determining the cellular function such as pH, pO2 , and Ca(2+) are required. This review is focused on the progress in the design, fabrication, and application of photoluminescent nanoprobes for sensing and imaging of pH in living cells. The advantages of using nanoprobes carrying fluorescent pH indicators compared to single molecule probes are discussed as well as their limitations due to the mostly lysosomal uptake by cells. Particular attention is paid to ratiometric dual wavelength nanosensors that enable intrinsic referenced measurements. Referencing and proper calibration procedures are basic prerequisites to carry out reliable quantitative pH determinations in complex samples such as living cells. A variety of examples will be presented that highlight the diverseness of nanocarrier materials (polymers, micelles, silica, quantum dots, carbon dots, gold, photon upconversion nanocrystals, or bacteriophages), fluorescent pH indicators for the weak acidic range, and referenced sensing mechanisms, that have been applied intracellularly up to now. WIREs Nanomed Nanobiotechnol 2016, 8:378-413. doi: 10.1002/wnan.1366 For further resources related to this article, please visit the WIREs website. © 2015 Wiley Periodicals, Inc.

T1ρ-weighted Dynamic Glucose-enhanced MR Imaging in the Human Brain.

Science.gov (United States)

Paech, Daniel; Schuenke, Patrick; Koehler, Christina; Windschuh, Johannes; Mundiyanapurath, Sibu; Bickelhaupt, Sebastian; Bonekamp, David; Bäumer, Philipp; Bachert, Peter; Ladd, Mark E; Bendszus, Martin; Wick, Wolfgang; Unterberg, Andreas; Schlemmer, Heinz-Peter; Zaiss, Moritz; Radbruch, Alexander

2017-12-01

Purpose To evaluate the ability to detect intracerebral regions of increased glucose concentration at T1ρ-weighted dynamic glucose-enhanced (DGE) magnetic resonance (MR) imaging at 7.0 T. Materials and Methods This prospective study was approved by the institutional review board. Nine patients with newly diagnosed glioblastoma and four healthy volunteers were included in this study from October 2015 to July 2016. Adiabatically prepared chemical exchange-sensitive spin-lock imaging was performed with a 7.0-T whole-body unit with a temporal resolution of approximately 7 seconds, yielding the time-resolved DGE contrast. T1ρ-weighted DGE MR imaging was performed with injection of 100 mL of 20% d-glucose via the cubital vein. Glucose enhancement, given by the relative signal intensity change at T1ρ-weighted MR imaging (DGEρ), was quantitatively investigated in brain gray matter versus white matter of healthy volunteers and in tumor tissue versus normal-appearing white matter of patients with glioblastoma. The median signal intensities of the assessed brain regions were compared by using the Wilcoxon rank-sum test. Results In healthy volunteers, the median signal intensity in basal ganglia gray matter (DGEρ = 4.59%) was significantly increased compared with that in white matter tissue (DGEρ = 0.65%) (P = .028). In patients, the median signal intensity in the glucose-enhanced tumor region as displayed on T1ρ-weighted DGE images (DGEρ = 2.02%) was significantly higher than that in contralateral normal-appearing white matter (DGEρ = 0.08%) (P brain glucose physiology and pathophysiologically increased glucose uptake and may have the potential to provide information about glucose metabolism in tumor tissue. © RSNA, 2017 Online supplemental material is available for this article.

Lesions inflammatory activity quantification in multiple sclerosis using ["1"1C]-(R)-PK11195 PET brain images

International Nuclear Information System (INIS)

Schuck, Phelipi N.; Narciso, Lucas D.L.; Dartora, Caroline M.; Silva, Ana M. Marques da

2016-01-01

The criteria for multiple sclerosis (MS) diagnosis include the presence of lesions in brain regions called black holes (BH), characterized by low signal on magnetic resonance imaging T1-weighted. Studies suggest that lesions in MS, if there is an inflammatory process, can be detected in PET imaging with ["1"1C]- (R)-PK11195. The aim of this study is to investigate the uptake of ["1"1C]-(R)-PK11195 in BH in PET images, searching for inflammation activity in lesions and neighborhoods. Semiquantitative methods of SUV and uptake normalization were applied to PET images, in different time intervals, acquired from 8 MS patients and 5 healthy controls. Higher uptake was identified in BH and its edges, when compared with health controls white matter, when the SUV method is applied (p < 0,01, 40 to 60 min). When uptake normalization method is applied, smaller uptake in black holes and its your edges is observed, when compared with white matter apparently healthy (p < 0,01, 0 to 60 min). (author)

Imaging and measurement of T1 value by NMR of low magnetic field

International Nuclear Information System (INIS)

Asai, Hideaki; Izawa, Akira; Furuse, Kazuhiro; Saoi, Katsuyoshi; Nagai, Masahiko.

1983-01-01

FONAR QED-80α having two operating mode: the anatomy mode to obtain an image of proton densities and the chemistry mode to measure T 1 value at a region of intenst, was used clinically. The strength of static magnetic field is 0.041T. 32 cases, 18 healthy volunteers and 14 patients were studied. In proton density imaging, high proton density organs such as skin were imaged bright, and low proton density organs such as bones and flowing blood were imaged dark. The merits of NMR imaging are no artifacts caused by bones and air. However, NMR image is required long time for measurement and the image of NMR is unsharp than that of X-ray CT. Concerning with T 1 value, cerebral and cerebellar gray matter had longer T 1 's than that of white matter. Pathological lesions, such as tumor and/or infarct, had also longer T 1 values than these of normal tissue. The value of T 1 was thought to be applicable clinically except for some problems, such as measuring T 1 value of large extent. No side effects were found during and after examinations. (author)

New far infrared images of bright, nearby, star-forming regions

Science.gov (United States)

Harper, D. AL, Jr.; Cole, David M.; Dowell, C. Darren; Lees, Joanna F.; Lowenstein, Robert F.

1995-01-01

Broadband imaging in the far infrared is a vital tool for understanding how young stars form, evolve, and interact with their environment. As the sensitivity and size of detector arrays has increased, a richer and more detailed picture has emerged of the nearest and brightest regions of active star formation. We present data on M 17, M 42, and S 106 taken recently on the Kuiper Airborne Observatory with the Yerkes Observatory 60-channel far infrared camera, which has pixel sizes of 17 in. at 60 microns, 27 in. at 100 microns, and 45 in. at 160 and 200 microns. In addition to providing a clearer view of the complex central cores of the regions, the images reveal new details of the structure and heating of ionization fronts and photodissociation zones where radiation form luminous stars interacts with adjacent molecular clouds.

The Desired Image of the Future Economy of the Industrial Region: Development Trends and Evaluation Methodology

Directory of Open Access Journals (Sweden)

Olga Aleksandrovna Romanova

2017-09-01

Full Text Available In the article, the authors emphasize that industrial regions play an important role in the increasing of technological independence of Russia. We show that the decline in the share of processing industries in the gross regional product can not be treated as a negative de-industrialization of the economy. The article proves that the increase in the speed of changements, instability of socio-economic systems, the diverse risks predetermine the need to develop new methodological approaches to predictive research. The studies aimed at developing a technology for the design of the desired image of the future and the methodology for its evaluation are of high importance. For the initial stage of the research, the authors propose the methodological approach for assessing the desired image of the future of metallurgy as one of the most important industry of the region. We propose the term of «technological image of the regional metallurgy». We show that repositioning the image of the regional metallurgical complex is quite a long process. This have determined the need to define the stages of repositioning. The proposed methodology of the evaluation of desired future includes the methodological provisions to quantify the characteristics of goals achieved at the respective stages of the repositioning of the metallurgy. The methodological approach to the design of the desired image of the future implies the following stages: the identification of the priority areas of the technological development of regional metallurgy on the basis of bibliometric and patent analysis; the evaluation of dynamics of the development of the structure of metal products domestic consumption based on comparative analysis and relevant analytical methods as well as its forecasting; the design of the factor model, allowing to identify the parameters quantifying the technological image of the regional metallurgy based on the principal components method,; systematization of

Regional left ventricular contractile dynamics in hypertrophic cardiomyopathy estimated by magnetic resonance imaging

International Nuclear Information System (INIS)

Sato, Tetsuya

1994-01-01

To assess the regional myocardial function in hypertrophic cardiomyopathy (HCM), I examined the systolic wall thickening (%WT) and percent change of segmental wall area (%AR) using cine magnetic resonance imaging in 23 normal volunteers (G1) and 40 patients (G2) with HCM. Short axis images of the left ventricle were recorded at the base and the apex, and were divided into 5 segments, and %WT and %AR were measured for each segment. There were no significant differences in %WT and %AR among the segments in G1, while %WT of the posterior septum, posterior and lateral segments in the apex were higher than the corresponding segments of the base. Wall segments of G2 were classified into 3 groups according to the end-diastolic wall thickness: G2a, ≤12 mm; G2b, 12 15. At each slice level, %WT and %AR were highest in G2a and lowest in G2c. These findings suggest that myocardial shortening in normal subjects is higher in the apex than in the base, and, in HCM, regional myocardial function decreases in association with an advance of hypertrophy, with a possible compensatory increased wall function of normal segments. (author)

Cerebral activation during motor imagery in complex regional pain syndrome type 1 with dystonia

NARCIS (Netherlands)

Gieteling, Esther W.; van Rijn, Monique A.; de Jong, Bauke M.; Hoogduin, Johannes M.; Renken, Remco; van Hilten, Jacobus J.; Leenders, Klaus L.

The pathogenesis of dystonia in Complex Regional Pain Syndrome type 1 (CRPS-1) is unclear. In primary dystonia, functional magnetic resonance imaging (fMRI) has revealed changes in cerebral networks during execution of movement. The aim of this study was to determine cerebral network function in

A morphological study of the mandibular molar region using reconstructed helical computed tomographic images

International Nuclear Information System (INIS)

Tsuno, Hiroaki; Noguchi, Makoto; Noguchi, Akira; Yoshida, Keiko; Tachinami, Yasuharu

2010-01-01

This study investigated the morphological variance in the mandibular molar region using reconstructed helical computed tomographic (CT) images. In addition, we discuss the necessity of CT scanning as part of the preoperative assessment process for dental implantation, by comparing the results with the findings of panoramic radiography. Sixty patients examined using CT as part of the preoperative assessment for dental implantation were analyzed. Reconstructed CT images were used to evaluate the bone quality and cross-sectional bone morphology of the mandibular molar region. The mandibular cortical index (MCI) and X-ray density ratio of this region were assessed using panoramic radiography in order to analyze the correlation between the findings of the CT images and panoramic radiography. CT images showed that there was a decrease in bone quality in cases with high MCI. Cross-sectional CT images revealed that the undercuts on the lingual side in the highly radiolucent areas in the basal portion were more frequent than those in the alveolar portion. This study showed that three-dimensional reconstructed CT images can help to detect variances in mandibular morphology that might be missed by panoramic radiography. In conclusion, it is suggested that CT should be included as an important examination tool before dental implantation. (author)

Cell nuclei segmentation in fluorescence microscopy images using inter- and intra-region discriminative information.

Science.gov (United States)

Song, Yang; Cai, Weidong; Feng, David Dagan; Chen, Mei

2013-01-01

Automated segmentation of cell nuclei in microscopic images is critical to high throughput analysis of the ever increasing amount of data. Although cell nuclei are generally visually distinguishable for human, automated segmentation faces challenges when there is significant intensity inhomogeneity among cell nuclei or in the background. In this paper, we propose an effective method for automated cell nucleus segmentation using a three-step approach. It first obtains an initial segmentation by extracting salient regions in the image, then reduces false positives using inter-region feature discrimination, and finally refines the boundary of the cell nuclei using intra-region contrast information. This method has been evaluated on two publicly available datasets of fluorescence microscopic images with 4009 cells, and has achieved superior performance compared to popular state of the art methods using established metrics.

CT perfusion imaging on the disturbance of regional cerebral microcirculation in a pre-infarction period: an experimental study

International Nuclear Information System (INIS)

Gao Peiyi; Liang Chenyang; Lin Yan; Yuan Fang; Hu Ling

2003-01-01

Objective: To investigate the CT perfusion imaging and the pathological features on the disturbance of regional cerebral microcirculation in a pre-infarction period, and to evaluate the relationship between the astrocytes and regional cerebral microcirculation. Methods: Dynamic CT perfusion imaging of the models with regional cerebral hypoperfusion and astrocytic swelling in rats was performed to assess the presence or absence of the disturbance of regional cerebral microcirculation. Then, the histopathologic examination was made for both models, respectively. The ratios of side-to-side were measured at hypoperfusion areas in the models of regional cerebral ischemia. Results: Regional hypoperfusion was revealed by regional cerebral blood flow (rCBF) and mean transit time (MTT) maps in the group of hypoperfusion for 6 hours. Regional cerebral blood volume (rCBV) and time-to-peak (TTP) maps were normal in that group. The ratios of rCBF, rCBV, MTT and TTP were 0.39-0.55, 0.92-1.00, 1.20-1.50 and 1.00-1.00 respectively. Astrocytic swelling pressing the capillary wall was obvious and subtle neuronal reversible degeneration was occasionally found. TTC stain was normal. In the tACPD group of astrocytic swelling, the abnormal hemodynamic regions on rCBF and MTT maps were found. The rCBV maps of 3 rats in the tACPD group showed the area of reduced rCBV. In 2 rats of tACPD group, the areas of delayed TTP were also found. The ratios of rCBF, rCBV, MTT and TTP were 0.25-0.44, 0.70-1.01, 1.20-2.00 and 1.02-1.45 respectively. TTC stain was negative. Electron microscope study revealed remarkable swelling of astrocytes, especially endfoot processes of astrocytes around capillaries. The abnormal hemodynamic region on rCBF and MTT maps matched with abnormal extent on histopathologic examination. The rCBV and TTP maps appeared normal. Conclusion: The astrocytes can react in a way faster than the neurons in the pre-infarction period, viz. astrocytic swelling. The swelling of

Investigation of four-dimensional computed tomography-based pulmonary ventilation imaging in patients with emphysematous lung regions

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Tokihiro; Loo, Billy W Jr; Keall, Paul J [Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Dr, Stanford, CA 94305-5847 (United States); Kabus, Sven; Lorenz, Cristian; Von Berg, Jens; Blaffert, Thomas [Department of Digital Imaging, Philips Research Europe, Roentgenstrasse 24-26, D-22335 Hamburg (Germany); Klinder, Tobias, E-mail: Tokihiro@stanford.edu [Clinical Informatics, Interventional, and Translational Solutions, Philips Research North America, Briarcliff Manor, NY 10510 (United States)

2011-04-07

A pulmonary ventilation imaging technique based on four-dimensional (4D) computed tomography (CT) has advantages over existing techniques. However, physiologically accurate 4D-CT ventilation imaging has not been achieved in patients. The purpose of this study was to evaluate 4D-CT ventilation imaging by correlating ventilation with emphysema. Emphysematous lung regions are less ventilated and can be used as surrogates for low ventilation. We tested the hypothesis: 4D-CT ventilation in emphysematous lung regions is significantly lower than in non-emphysematous regions. Four-dimensional CT ventilation images were created for 12 patients with emphysematous lung regions as observed on CT, using a total of four combinations of two deformable image registration (DIR) algorithms: surface-based (DIR{sup sur}) and volumetric (DIR{sup vol}), and two metrics: Hounsfield unit (HU) change (V{sub HU}) and Jacobian determinant of deformation (V{sub Jac}), yielding four ventilation image sets per patient. Emphysematous lung regions were detected by density masking. We tested our hypothesis using the one-tailed t-test. Visually, different DIR algorithms and metrics yielded spatially variant 4D-CT ventilation images. The mean ventilation values in emphysematous lung regions were consistently lower than in non-emphysematous regions for all the combinations of DIR algorithms and metrics. V{sub HU} resulted in statistically significant differences for both DIR{sup sur} (0.14 {+-} 0.14 versus 0.29 {+-} 0.16, p = 0.01) and DIR{sup vol} (0.13 {+-} 0.13 versus 0.27 {+-} 0.15, p < 0.01). However, V{sub Jac} resulted in non-significant differences for both DIR{sup sur} (0.15 {+-} 0.07 versus 0.17 {+-} 0.08, p = 0.20) and DIR{sup vol} (0.17 {+-} 0.08 versus 0.19 {+-} 0.09, p = 0.30). This study demonstrated the strong correlation between the HU-based 4D-CT ventilation and emphysema, which indicates the potential for HU-based 4D-CT ventilation imaging to achieve high physiologic accuracy. A

Nucleus and cytoplasm segmentation in microscopic images using K-means clustering and region growing.

Science.gov (United States)

Sarrafzadeh, Omid; Dehnavi, Alireza Mehri

2015-01-01

Segmentation of leukocytes acts as the foundation for all automated image-based hematological disease recognition systems. Most of the time, hematologists are interested in evaluation of white blood cells only. Digital image processing techniques can help them in their analysis and diagnosis. The main objective of this paper is to detect leukocytes from a blood smear microscopic image and segment them into their two dominant elements, nucleus and cytoplasm. The segmentation is conducted using two stages of applying K-means clustering. First, the nuclei are segmented using K-means clustering. Then, a proposed method based on region growing is applied to separate the connected nuclei. Next, the nuclei are subtracted from the original image. Finally, the cytoplasm is segmented using the second stage of K-means clustering. The results indicate that the proposed method is able to extract the nucleus and cytoplasm regions accurately and works well even though there is no significant contrast between the components in the image. In this paper, a method based on K-means clustering and region growing is proposed in order to detect leukocytes from a blood smear microscopic image and segment its components, the nucleus and the cytoplasm. As region growing step of the algorithm relies on the information of edges, it will not able to separate the connected nuclei more accurately in poor edges and it requires at least a weak edge to exist between the nuclei. The nucleus and cytoplasm segments of a leukocyte can be used for feature extraction and classification which leads to automated leukemia detection.

A Means for the Scintigraphic Imaging of Regional Brain Dynamics. Regional Cerebral Blood Flow and Regional Cerebral Blood Volume

Energy Technology Data Exchange (ETDEWEB)

Potchen, E. J.; Bentley, R.; Gerth, W.; Hill, R. L.; Davis, D. O. [Washington University School Of Medicine, St. Louis, MO (United States)

1969-05-15

The use of freely diffusable inert radioactive gas as a washout indicator to measure regional cerebral blood flow has become a standardized kinetic procedure in many laboratories. Recent investigations with this technique have led us to conclude that we can reliably distinguish regional flow with perfusion against regional flow without perfusion from the early portion of the curve. Based on a detailed study of the early curve kinetics in patients with and without cerebral vascular disease we have defined the sampling duration necessary for application of the Anger gamma camera imaging process to regional changes in cerebral radioactivity. Using a standard camera and a small computer, a procedure has been developed and based upon entire field to determine the time of maximum height followed by analysis of the data in a matrix. This will permit a contour plot presentation of calculated regional cerebral blood flow in millilitres per 100 grams perfused brain per minute. In addition, we propose to augment this data by the display of regional non-perfusion blood flow versus regional cerebral flow with perfusion. Preliminary investigation on sampling duration, and Compton scattering were prerequisite to clinical scintigraphy of regional cerebral blood flow. In addition, the method of interface for the conventional Anger gamma camera to digital computers used in this procedure are discussed. Applications to further assess regional cerebral dynamics by scintigraphy are presented. (author)

Near-infrared imaging polarimetry of bipolar nebulae: Pt. 1

International Nuclear Information System (INIS)

Minchin, N.R.; Hough, J.H.; McCall, A.; Burton, M.G.; McCaughrean, M.J.; Aspin, C.; Bailey, J.A.; Axon, D.J.; Sato, Shuji

1991-01-01

New high-spatial-resolution polarization images of the BN-KL region of OMC-1 from 1.25-3.6 μm are presented. At the longer wavelengths these show a centro-symmetric polarization vector pattern, centred mainly on IRc2, and high degrees of polarization across the nebula, confirming that the diffuse nebulosity is dominated by the scattering of radiation, mainly from IRc2. Degrees of polarization, position angles and magnitudes are given for the observable IRc sources. These are discussed. (author)

Determining the source region of auroral emissions in the prenoon oval using coordinated Polar BEAR UV-imaging and DMSP particle measurements

International Nuclear Information System (INIS)

Newell, P.T.; Meng, C.I.; Huffman, R.E.

1992-01-01

The Polar Beacon Experiment and Auroral Research (Polar BEAR) satellite included the capability for imaging the dayside auroral oval in full sunlight at several wavelengths. The authors compare particle observations from the DMSP F7 satellite during dayside auroral oval crossings with approximately simultaneous Polar BEAR 1,356-angstrom images to determine the magnetospheric source region of the dayside auroral oval. The source region is determined from the Defense Meteorological Satellite Program (DMSP) particle data, according to recent work concerning the classification and identification of precipitation source regions. The close DMSP/Polar BEAR coincidences all occur when the former satellite is located between 0945 and 1,000 MLT. The authors found instances of auroral arcs mapping to each of several different regions, including the boundary plasma sheet, the low-latitude boundary layer, and the plasma mantle. However, the results indicate that about half the time the most prominent auroral arcs are located at the interfaces between distinct plasma regions, at least at the local time studied here

Regional alternative transportation evaluation report - region 1

Science.gov (United States)

2011-01-21

The U.S. Fish and Wildlife Service (FWS) and the U.S. Department of Transportation (DOT) Volpe Center (Volpe Center) conducted a regional alternative transportation evaluation (RATE) in Region 1, which is comprised of Oregon, Idaho, Washington, and H...

Mapping pathological changes in brain structure by combining T1- and T2-weighted MR imaging data

International Nuclear Information System (INIS)

Ganzetti, Marco; Mantini, Dante; Wenderoth, Nicole

2015-01-01

A workflow based on the ratio between standardized T1-weighted (T1-w) and T2-weighted (T2-w) MR images has been proposed as a new tool to study brain structure. This approach was previously used to map structural properties in the healthy brain. Here, we evaluate whether the T1-w/T2-w approach can support the assessment of structural impairments in the diseased brain. We use schizophrenia data to demonstrate the potential clinical utility of the technique. We analyzed T1-w and T2-w images of 36 schizophrenic patients and 35 age-matched controls. These were collected for the Function Biomedical Informatics Research Network (fBIRN) collaborative project, which had an IRB approval and followed the HIPAA guidelines. We computed T1-w/T2-w images for each individual and compared intensities in schizophrenic and control groups on a voxel-wise basis, as well as in regions of interest (ROIs). Our results revealed that the T1-w/T2-w image permits to discriminate brain regions showing group-level differences between patients and controls with greater accuracy than conventional T1-w and T2-w images. Both the ROIs and the voxel-wise analysis showed globally reduced gray and white matter values in patients compared to controls. Significantly reduced values were found in regions such as insula, primary auditory cortex, hippocampus, inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus. Our findings were consistent with previous meta-analyses in schizophrenia corroborating the hypothesis of a potential ''disconnection'' syndrome in conjunction with structural alterations in local gray matter regions. Overall, our study suggested that the T1-w/T2-w technique permits to reliably map structural differences between the brains of patients and healthy individuals. (orig.)

Mapping pathological changes in brain structure by combining T1- and T2-weighted MR imaging data

Energy Technology Data Exchange (ETDEWEB)

Ganzetti, Marco; Mantini, Dante [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); University of Oxford, Department of Experimental Psychology, Oxford (United Kingdom); Wenderoth, Nicole [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); KU Leuven, Laboratory of Movement Control and Neuroplasticity, Faculty of Kinesiology and Rehabilitation Sciences, Leuven (Belgium)

2015-09-15

A workflow based on the ratio between standardized T1-weighted (T1-w) and T2-weighted (T2-w) MR images has been proposed as a new tool to study brain structure. This approach was previously used to map structural properties in the healthy brain. Here, we evaluate whether the T1-w/T2-w approach can support the assessment of structural impairments in the diseased brain. We use schizophrenia data to demonstrate the potential clinical utility of the technique. We analyzed T1-w and T2-w images of 36 schizophrenic patients and 35 age-matched controls. These were collected for the Function Biomedical Informatics Research Network (fBIRN) collaborative project, which had an IRB approval and followed the HIPAA guidelines. We computed T1-w/T2-w images for each individual and compared intensities in schizophrenic and control groups on a voxel-wise basis, as well as in regions of interest (ROIs). Our results revealed that the T1-w/T2-w image permits to discriminate brain regions showing group-level differences between patients and controls with greater accuracy than conventional T1-w and T2-w images. Both the ROIs and the voxel-wise analysis showed globally reduced gray and white matter values in patients compared to controls. Significantly reduced values were found in regions such as insula, primary auditory cortex, hippocampus, inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus. Our findings were consistent with previous meta-analyses in schizophrenia corroborating the hypothesis of a potential ''disconnection'' syndrome in conjunction with structural alterations in local gray matter regions. Overall, our study suggested that the T1-w/T2-w technique permits to reliably map structural differences between the brains of patients and healthy individuals. (orig.)

Parental social anxiety disorder prospectively predicts toddlers' fear/avoidance in a social referencing paradigm

OpenAIRE

Aktar, E.; Majdandžić, M.; De, Vente W.; Bögels, S.M.

2014-01-01

Background: Anxiety runs in families. Observational learning of anxious behavior from parents with anxiety disorders plays an important role in the intergenerational transmission of anxiety. We investigated the link between parental anxiety (parental lifetime anxiety disorders and expressed parental anxiety) and toddler fear/avoidance during social referencing (SR) situations. Method: Toddlers (N = 117) participated with both parents (with lifetime social anxiety disorder, other nonsocial anx...

Nonresearch Industry Payments to Radiologists: Characteristics and Associations With Regional Medical Imaging Utilization.

Science.gov (United States)

Kokabi, Nima; Junn, Jacqueline C; Xing, Minzhi; Hemingway, Jennifer; Hughes, Danny R; Duszak, Richard

2017-03-01

To evaluate characteristics of nonresearch industry payments to radiologists and associations with regional diagnostic imaging utilization. Using 2014 CMS Open Payment data, all disclosed nonresearch-related industry payments to radiologists were identified. Health Resources and Services Administration Area Health Resources Files were used to identify actual and population-weighted numbers of radiologists by state. Utilizing the 5% random beneficiary sample CMS Research Identifiable Files from 2014, average Medicare imaging spending per beneficiary in each state was calculated. Average frequency and dollar amounts of nonresearch nonroyalty payments to radiologists were calculated at the state level. Using the Pearson correlation coefficient, the relationship between frequency and amounts of nonresearch payments to radiologists versus per-beneficiary Medicare imaging spending was evaluated at the state level. Overall, 2,008 radiologists (1,670 diagnostic, 338 interventional) received nonresearch nonroyalty payments from industry, representing 5.2% of all 38,857 radiologists nationwide. A total of 4,975 individual transfers translated to 2.5 ± 1.3 discrete payments per receiving radiologist with a mean of $432 ± $1,976 (median $26; range $1-$34,050). Food and beverage expenses constituted the vast majority of disclosed transfers (4,111; 83%), followed by travel and lodging (444; 9%), consulting fees (279; 6%), and educational expenses (51; 1%). Considerable geographic variation in payments was observed, ranging from 0% of radiologists in Vermont to 12.9% in the District of Columbia. No correlation was identified between average per-beneficiary Medicare imaging spending and the proportion of nonresearch-funded radiologists in each state (r = 0.06). Similarly, no correlation was identified between average per-beneficiary Medicare imaging spending and the average nonresearch transfer amount to radiologists in each state (r = -0.08). In 2014, only a small minority of

Selection, calibration and mosaicing of AMIE images to build a Moon Atlas as seen by SMART-1

Science.gov (United States)

Almeida, M.; Fonseca, J. M.; Grieger, B.; Costa, M.; Mora, A.

2014-04-01

In mid 2010 the European Space Agency opened the SMART-1 data to general public. The free access to these data opened new possibilities for its exploitation and use. In this dataset, there are data from the three instruments carried on-board: an ultracompact electronic camera to survey the lunar terrain in visible and near-infrared light (AMIE), an infrared spectrometer to analyze the Moon's minerals (SIR) and an X-ray spectrometer to identify key chemical elements in the lunar surface (D-CIXS). This work is focused on the AMIE captured images, that are used to produce a complete high-resolution atlas of the Moon. During the SMART-1 mission from 2004 to 2006, the onboard AMIE camera collected 31947 start-of-the-art (at the time) resolution and coverage images from lunar surface. However, a considerable number of images were contaminated with noise or suffered from transmission errors, being unusable for any purposes. Also, during the Earth escape phase the radiation damaged significantly the AMIE sensor invalidating the laboratorial flat field correction algorithm. This malfunction was compensated by a new calibration procedure based on in-flight images and theoretical models that will be presented on this paper. After flat field compensated, all images were also calibrated to compensate the sensor color filters at 750, 915 and 960 nm, designed for multi-spectral analysis, although now we use them as full-frame gray scale images. The resulting 1024x1024 images were geographically referenced using the in-board data and mosaiced considering illumination angle and image quality, in order to produce 88 lunar surface maps with lower resolution on the North Lunar pole (spacecraft apolune altitude of 3000Km) and higher resolution on the South Lunar pole (perilune altitude of 27Km). The final maps achieved a coverture of approximately 96% of the Lunar surface. For the latitudes higher than 60ºN and lower than 75ºS polar projection was used with a resolution of 300m

Magnetic resonance imaging. 1

International Nuclear Information System (INIS)

Wall, E.E. van der; Roos, A.A. de; Doornbos, J.; Dijkman, P.R.M. van; Matheijssen, N.A.A.; Laarse, A. van der; Krauss, X.H.; Blokland, J.A.k.; Manger Cats, V.; Voorthuisen, A.E. van; Bruschke, A.V.G.

1991-01-01

The cardiovascular applications of MRI in coronary artery disease have considerably increased in recent years. Although many applications overlap those of other more cost-effective techniques, such as echocardiography, radionuclide angiography, and CT, MRI offers unique features not shared by the conventional techniques. Technical advantages are the excellent spatial resolution, the characterization of myocardial tissue, and the potential for three-dimensional imaging. This allows the accurate assessment of left ventricular mass and volume, the differentiation of infarcted tissue from normal myocardial tissue, and the determination of systolic wall thickening and regional wall motion abnormalities. Also inducible myocardial ischemia using pharmacological stress (dipyramidole or dobutamine) may be assessed by magnetic resonance imaging. Future technical developments include real-time imaging and noninvasive visualization of the coronary arteries. These advantages will have a major impact on the application of MRI in coronary artery disease, potentially unsurpassed by other techniques and certainly justifying the expenses. Consequently, the clinical use of MRI for the detection of coronary artery disease largely depends on the progress of technical developments. (author). 134 refs.; 10 figs.; 2 tabs

A study on evaluating validity of SNR calculation using a conventional two region method in MR images applied a multichannel coil and parallel imaging technique

Energy Technology Data Exchange (ETDEWEB)

Choi, Kwan Woo; Son, Soon Yong [Dept. of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Min, Jung Whan [Dept. of Radiological Technology, Shingu University, Sungnam (Korea, Republic of); Kwon, Kyung Tae [Dept. of Radiological Technology, Dongnam Health University, Suwon (Korea, Republic of); Yoo, Beong Gyu; Lee, Jong Seok [Dept. of Radiotechnology, Wonkwang Health Science University, Iksan (Korea, Republic of)

2015-12-15

The purpose of this study was to investigate the problems of a signal to noise ratio measurement using a two region measurement method that is conventionally used when using a multi-channel coil and a parallel imaging technique. As a research method, after calculating the standard SNR using a single channel head coil of which coil satisfies three preconditions when using a two region measurement method, we made comparisons and evaluations after calculating an SNR by using a two region measurement method of which method is problematic because it is used without considering the methods recommended by reputable organizations and the preconditions at the time of using a multi-channel coil and a parallel imaging technique. We found that a two region measurement method using a multi-channel coil and a parallel imaging technique shows the highest relative standard deviation, and thus shows a low degree of precision. In addition, we found out that the difference of SNR according to ROI location was very high, and thus a spatial noise distribution was not uniform. Also, 95% confidence interval through Blend-Altman plot is the widest, and thus the conformity degree with a two region measurement method using the standard single channel head coil is low. By directly comparing an AAPM method, which serves as a standard of a performance evaluation test of a magnetic resonance imaging device under the same image acquisition conditions, an NEMA method which can accurately determine the noise level in a signal region and the methods recommended by manufacturers of a magnetic resonance imaging device, there is a significance in that we quantitatively verified the inaccurate problems of a signal to noise ratio using a two region measurement method when using a multi-channel coil and a parallel imaging technique of which method does not satisfy the preconditions that researchers could overlook.

Agreement Coefficients as Indices of Dependability for Domain-Referenced Tests. ACT Technical Bulletin No. 28.

Science.gov (United States)

Kane, Michael T.; Brennan, Robert L.

A large number of seemingly diverse coefficients have been proposed as indices of dependability, or reliability, for domain-referenced and/or mastery tests. In this paper, it is shown that most of these indices are special cases of two generalized indices of agreement: one that is corrected for chance, and one that is not. The special cases of…

Amperometric Self-Referencing Ceramic Based Microelectrode Arrays for D-Serine Detection.

Science.gov (United States)

Campos-Beltrán, Diana; Konradsson-Geuken, Åsa; Quintero, Jorge E; Marshall, Lisa

2018-03-06

D-serine is the major D-amino acid in the mammalian central nervous system. As the dominant co-agonist of the endogenous synaptic NMDA receptor, D-serine plays a role in synaptic plasticity, learning, and memory. Alterations in D-serine are linked to neuropsychiatric disorders including schizophrenia. Thus, it is of increasing interest to monitor the concentration of D-serine in vivo as a relevant player in dynamic neuron-glia network activity. Here we present a procedure for amperometric detection of D-serine with self-referencing ceramic-based microelectrode arrays (MEAs) coated with D-amino acid oxidase from the yeast Rhodotorula gracilis (RgDAAO). We demonstrate in vitro D-serine recordings with a mean sensitivity of 8.61 ± 0.83 pA/µM to D-serine, a limit of detection (LOD) of 0.17 ± 0.01 µM, and a selectivity ratio of 80:1 or greater for D-serine over ascorbic acid (mean ± SEM; n = 12) that can be used for freely moving studies.

Land cover in the Guayas Basin using SAR images from low resolution ASAR Global mode to high resolution Sentinel-1 images

Science.gov (United States)

Bourrel, Luc; Brodu, Nicolas; Frappart, Frédéric

2016-04-01

Remotely sensed images allow a frequent monitoring of land cover variations at regional and global scale. Recently launched Sentinel-1 satellite offers a global cover of land areas at an unprecedented spatial (20 m) and temporal (6 days at the Equator). We propose here to compare the performances of commonly used supervised classification techniques (i.e., k-nearest neighbors, linear and Gaussian support vector machines, naive Bayes, linear and quadratic discriminant analyzes, adaptative boosting, loggit regression, ridge regression with one-vs-one voting, random forest, extremely randomized trees) for land cover applications in the Guayas Basin, the largest river basin of the Pacific coast of Ecuator (area ~32,000 km²). The reason of this choice is the importance of this region in Ecuatorian economy as its watershed represents 13% of the total area of Ecuador where 40% of the Ecuadorian population lives. It also corresponds to the most productive region of Ecuador for agriculture and aquaculture. Fifty percents of the country shrimp farming production comes from this watershed, and represents with agriculture the largest source of revenue of the country. Similar comparisons are also performed using ENVISAT ASAR images acquired in global mode (1 km of spatial resolution). Accuracy of the results will be achieved using land cover map derived from multi-spectral images.

High-Performance Region-of-Interest Image Error Concealment with Hiding Technique

Directory of Open Access Journals (Sweden)

Shih-Chang Hsia

2010-01-01

Full Text Available Recently region-of-interest (ROI based image coding is a popular topic. Since ROI area contains much more important information for an image, it must be prevented from error decoding while suffering from channel lost or unexpected attack. This paper presents an efficient error concealment method to recover ROI information with a hiding technique. Based on the progressive transformation, the low-frequency components of ROI are encoded to disperse its information into the high-frequency bank of original image. The capability of protection is carried out with extracting the ROI coefficients from the damaged image without increasing extra information. Simulation results show that the proposed method can efficiently reconstruct the ROI image when ROI bit-stream occurs errors, and the measurement of PSNR result outperforms the conventional error concealment techniques by 2 to 5 dB.

REGION OF NON-INTEREST BASED DIGITAL IMAGE WATERMARKING USING NEURAL NETWORKS

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Bibi Isac

2011-11-01

Full Text Available Copyrights protection of digital data become inevitable in current world. Digital watermarks have been recently proposed as secured scheme for copyright protection, authentication, source tracking, and broadcast monitoring of video, audio, text data and digital images. In this paper a method to embed a watermark in region of non-interest (RONI and a method for adaptive calculation of strength factor using neural network are proposed. The embedding and extraction processes are carried out in the transform domain by using Discrete Wavelet Transform (DWT. Finally, the algorithm robustness is tested against noise addition attacks and geometric distortion attacks. The results authenticate that the proposed watermarking algorithm does not degrade the quality of cover image as the watermark is inserted only in region of non-interest and is resistive to attacks.

Application of SVM on satellite images to detect hotspots in Jharia coal field region of India

Energy Technology Data Exchange (ETDEWEB)

Gautam, R.S.; Singh, D.; Mittal, A.; Sajin, P. [Indian Institute for Technology, Roorkee (India)

2008-07-01

The present paper deals with the application of Support Vector Machine (SVM) and image analysis techniques on NOAA/AVHRR satellite image to detect hotspots on the Jharia coal field region of India. One of the major advantages of using these satellite data is that the data are free with very good temporal resolution; while, one drawback is that these have low spatial resolution (i.e., approximately 1.1 km at nadir). Therefore, it is important to do research by applying some efficient optimization techniques along with the image analysis techniques to rectify these drawbacks and use satellite images for efficient hotspot detection and monitoring. For this purpose, SVM and multi-threshold techniques are explored for hotspot detection. The multi-threshold algorithm is developed to remove the cloud coverage from the land coverage. This algorithm also highlights the hotspots or fire spots in the suspected regions. SVM has the advantage over multi-thresholding technique that it can learn patterns from the examples and therefore is used to optimize the performance by removing the false points which are highlighted in the threshold technique. Both approaches can be used separately or in combination depending on the size of the image. The RBF (Radial Basis Function) kernel is used in training of three sets of inputs: brightness temperature of channel 3, Normalized Difference Vegetation Index (NDVI) and Global Environment Monitoring Index (GEMI), respectively. This makes a classified image in the output that highlights the hotspot and non-hotspot pixels. The performance of the SVM is also compared with the performance obtained from the neural networks and SVM appears to detect hotspots more accurately (greater than 91% classification accuracy) with lesser false alarm rate. The results obtained are found to be in good agreement with the ground based observations of the hotspots.

Sally Ride EarthKAM - Automated Image Geo-Referencing Using Google Earth Web Plug-In

Science.gov (United States)

Andres, Paul M.; Lazar, Dennis K.; Thames, Robert Q.

2013-01-01

Sally Ride EarthKAM is an educational program funded by NASA that aims to provide the public the ability to picture Earth from the perspective of the International Space Station (ISS). A computer-controlled camera is mounted on the ISS in a nadir-pointing window; however, timing limitations in the system cause inaccurate positional metadata. Manually correcting images within an orbit allows the positional metadata to be improved using mathematical regressions. The manual correction process is time-consuming and thus, unfeasible for a large number of images. The standard Google Earth program allows for the importing of KML (keyhole markup language) files that previously were created. These KML file-based overlays could then be manually manipulated as image overlays, saved, and then uploaded to the project server where they are parsed and the metadata in the database is updated. The new interface eliminates the need to save, download, open, re-save, and upload the KML files. Everything is processed on the Web, and all manipulations go directly into the database. Administrators also have the control to discard any single correction that was made and validate a correction. This program streamlines a process that previously required several critical steps and was probably too complex for the average user to complete successfully. The new process is theoretically simple enough for members of the public to make use of and contribute to the success of the Sally Ride EarthKAM project. Using the Google Earth Web plug-in, EarthKAM images, and associated metadata, this software allows users to interactively manipulate an EarthKAM image overlay, and update and improve the associated metadata. The Web interface uses the Google Earth JavaScript API along with PHP-PostgreSQL to present the user the same interface capabilities without leaving the Web. The simpler graphical user interface will allow the public to participate directly and meaningfully with EarthKAM. The use of

Painful ankle region in rheumatoid arthritis. Analysis of soft-tissue changes with ultrasonography and MR imaging

Energy Technology Data Exchange (ETDEWEB)

Lehtinen, A. [Dept. of Radiology, Univ. Central Hospital, Helsinki (Finland); Paimela, L. [Dept of Rheumatology, Helsinki City Hospital (Finland); Kreula, J. [Dept. of Radiology, Univ. Central Hospital, Helsinki (Finland); Leirisalo-Repo, M. [Dept of Medicine, Univ. Central Hospital, Helsinki (Finland); Taavitsainen, M. [Dept. of Radiology, Univ. Central Hospital, Helsinki (Finland)

1996-07-01

Purpose: To establish the diagnostic usefulness of ultrasonography (US) and MR imaging in patients with rheumatoid arthritis (RA) suffering from prolonged pain in the ankle region, where plain radiography did not demonstrate any changes. Material and Methods: Seventeen patients were studied with 0.1 T MR imaging and with high-frequency US. Talocrural and subtalar joints (including talonavicular joints), and medial, lateral, and extensor tendons and their synovial sheaths were examined b MR and US. Results: Abnormal findings were found by MR imaging and US in altogether 76% of the patients, by MR alone in 53%, and by US alone in 59%. In 41% of the patients, lesions were demonstrated only by one method. Talocurural and subtalar joints were the most often affected sites (41% each), followed by the peroneus tendon (23%). In the joints, the abnormal findings were interpreted as synovitis; in the tendon areas, mostly as tenosynovitis. MR and US were highly significantly concordant (p<0.0001), but correlation with clinical features was poor. Conclusion: In patients with pain in the ankle region, US and MR imaging can contribute to the diagnosis and localization of the abnormality when the plain radiography is normal Easily available and inexpensive US can be recommended as the first imaging method after plain radiography. Some divergence seems to exist between US and MR, and in complicated cases both methods are recommended. (orig.).

Painful ankle region in rheumatoid arthritis. Analysis of soft-tissue changes with ultrasonography and MR imaging

International Nuclear Information System (INIS)

Lehtinen, A.; Paimela, L.; Kreula, J.; Leirisalo-Repo, M.; Taavitsainen, M.

1996-01-01

Purpose: To establish the diagnostic usefulness of ultrasonography (US) and MR imaging in patients with rheumatoid arthritis (RA) suffering from prolonged pain in the ankle region, where plain radiography did not demonstrate any changes. Material and Methods: Seventeen patients were studied with 0.1 T MR imaging and with high-frequency US. Talocrural and subtalar joints (including talonavicular joints), and medial, lateral, and extensor tendons and their synovial sheaths were examined b MR and US. Results: Abnormal findings were found by MR imaging and US in altogether 76% of the patients, by MR alone in 53%, and by US alone in 59%. In 41% of the patients, lesions were demonstrated only by one method. Talocurural and subtalar joints were the most often affected sites (41% each), followed by the peroneus tendon (23%). In the joints, the abnormal findings were interpreted as synovitis; in the tendon areas, mostly as tenosynovitis. MR and US were highly significantly concordant (p<0.0001), but correlation with clinical features was poor. Conclusion: In patients with pain in the ankle region, US and MR imaging can contribute to the diagnosis and localization of the abnormality when the plain radiography is normal Easily available and inexpensive US can be recommended as the first imaging method after plain radiography. Some divergence seems to exist between US and MR, and in complicated cases both methods are recommended. (orig.)

New Region-Scalable Discriminant and Fitting Energy Functional for Driving Geometric Active Contours in Medical Image Segmentation

Directory of Open Access Journals (Sweden)

Xuchu Wang

2014-01-01

that uses region-scalable discriminant and fitting energy functional for handling the intensity inhomogeneity and weak boundary problems in medical image segmentation. The region-scalable discriminant and fitting energy functional is defined to capture the image intensity characteristics in local and global regions for driving the evolution of active contour. The discriminant term in the model aims at separating background and foreground in scalable regions while the fitting term tends to fit the intensity in these regions. This model is then transformed into a variational level set formulation with a level set regularization term for accurate computation. The new model utilizes intensity information in the local and global regions as much as possible; so it not only handles better intensity inhomogeneity, but also allows more robustness to noise and more flexible initialization in comparison to the original global region and regional-scalable based models. Experimental results for synthetic and real medical image segmentation show the advantages of the proposed method in terms of accuracy and robustness.

Fully automated rodent brain MR image processing pipeline on a Midas server: from acquired images to region-based statistics.

Science.gov (United States)

Budin, Francois; Hoogstoel, Marion; Reynolds, Patrick; Grauer, Michael; O'Leary-Moore, Shonagh K; Oguz, Ipek

2013-01-01

Magnetic resonance imaging (MRI) of rodent brains enables study of the development and the integrity of the brain under certain conditions (alcohol, drugs etc.). However, these images are difficult to analyze for biomedical researchers with limited image processing experience. In this paper we present an image processing pipeline running on a Midas server, a web-based data storage system. It is composed of the following steps: rigid registration, skull-stripping, average computation, average parcellation, parcellation propagation to individual subjects, and computation of region-based statistics on each image. The pipeline is easy to configure and requires very little image processing knowledge. We present results obtained by processing a data set using this pipeline and demonstrate how this pipeline can be used to find differences between populations.

High intensity region segmentation in MR imaging of multiple sclerosis

International Nuclear Information System (INIS)

Rodrigo, F; Filipuzzi, M; Graffigna, J P; Isoardi, R; Noceti, M

2013-01-01

Numerous pathologies are often manifest in Magnetic Resonance Imaging (MRI) as hyperintense or bright regions as compared to normal tissue. It is of particular interest to develop an algorithm to detect, identify and define those Regions of Interest (ROI) when analyzing MRI studies, particularly for lesions of Multiple Sclerosis (MS). The objective of this study is to analyze those parameters which optimize segmentation of the areas of interest. To establish which areas should be considered as hyperintense regions, we developed a database (DB), with studies of patients diagnosed with MS. This disease causes axonal demyelination and it is expressed as bright regions in PD, T2 and FLAIR MRI sequences. Thus, with more than 4300 hyperintense regions validated by an expert physician, an algorithm was developed to detect such spots, approximating the results the expert obtained. Alongside these hyperintense lesion regions, it also detected bone regions with high intensity levels, similar to the intensity of the lesions, but with other features that allow a good differentiation.The algorithm will then detect ROIs with similar intensity levels and performs classification through data mining techniques

Proton nuclear magnetic resonance imaging of regionally ischemic canine hearts: effects of paramagnetic proton signal enhancement

International Nuclear Information System (INIS)

Brady, T.J.; Goldman, M.R.; Pykett, I.L.; Buonanno, F.S.; Kistler, J.P.; Newhouse, J.H.; Burt, C.T.; Hinshaw, W.S.; Pohost, G.M.

1982-01-01

In a study to evaluate the potential of proton nuclear magnetic resonance (NMR) imaging with and without manganese contrast enhancement for detecting acute myocardial infarction, 12 dogs underwent 90-minute occlusion of the left circumflex coronary artery. Transverse-section NMR images of the excised, nonbeating heart were obtained at 1-cm intervals using the steady-state-free-precession (SSFP) technique. All NMR images revealed detailed structure of the heart. The three hearts without manganese showed no difference in intensity between the normal and the ischemic posterior regions, whereas those with manganese demonstrated a clearly demarcated zone of reduced signal intensity consistent with the ischemic zone. It is concluded that high-resolution tomograms of the excised canine myocardium can be obtained using proton NMR imaging. With the SSFP imaging technique, proton signal enhancement with manganese infusion is necessary to differentiate between ischemic and nonischemic myocardium after 90 minutes of coronary occlusion

Classification of semiurban landscapes from very high-resolution satellite images using a regionalized multiscale segmentation approach

Science.gov (United States)

Kavzoglu, Taskin; Erdemir, Merve Yildiz; Tonbul, Hasan

2017-07-01

In object-based image analysis, obtaining representative image objects is an important prerequisite for a successful image classification. The major threat is the issue of scale selection due to the complex spatial structure of landscapes portrayed as an image. This study proposes a two-stage approach to conduct regionalized multiscale segmentation. In the first stage, an initial high-level segmentation is applied through a "broadscale," and a set of image objects characterizing natural borders of the landscape features are extracted. Contiguous objects are then merged to create regions by considering their normalized difference vegetation index resemblance. In the second stage, optimal scale values are estimated for the extracted regions, and multiresolution segmentation is applied with these settings. Two satellite images with different spatial and spectral resolutions were utilized to test the effectiveness of the proposed approach and its transferability to different geographical sites. Results were compared to those of image-based single-scale segmentation and it was found that the proposed approach outperformed the single-scale segmentations. Using the proposed methodology, significant improvement in terms of segmentation quality and classification accuracy (up to 5%) was achieved. In addition, the highest classification accuracies were produced using fine-scale values.

Magnetic resonance imaging and three-dimensional ultrasound of carotid atherosclerosis: mapping regional differences.

Science.gov (United States)

Krasinski, Adam; Chiu, Bernard; Fenster, Aaron; Parraga, Grace

2009-04-01

To evaluate differences in carotid atherosclerosis measured using magnetic resonance imaging (MRI) and three-dimensional ultrasound (3DUS). Ten subject volunteers underwent carotid 3DUS and MRI (multislice black blood fast spin echo, T1-weighted contrast, double inversion recovery, 0.5 mm in-plane resolution, 2 mm slice, 3.0 T) within 1 hour. 3DUS and MR images were manually segmented by two observers providing vessel wall and lumen contours for quantification of vessel wall volume (VWV) and generation of carotid thickness maps. MRI VWV (1040 +/- 210 mm(3)) and 3DUS VWV (540 +/- 110 mm(3)) were significantly different (P Power Doppler US confirmed that heterogeneity in the common carotid artery in all patients resulted from apparent flow disturbances, not atherosclerotic plaque. MRI and 3DUS VWV were significantly different and carotid maps showed homogeneous thickness differences and heterogeneity in specific regions of interest identified as MR flow artifacts in the common carotid artery.

Comparison of 99mTc-MIBI Myocardial Uptake at Rest with Reinjection and 24-hour after Reinjection Images of 201T1

International Nuclear Information System (INIS)

Bom, Hee Seung; Kim, Ji Yeul; Park, Joo Hyung; Ahn, Young Keun; Jeong, Myung Ho; Cho, Jeong Gwan; Park, Jong Choon; Kang, Jung Chaee

1992-01-01

Clinical role of 99m Tc-MIBI myocardial scintigraphy in the diagnosis of coronary artery disease (CAD) is now well accepted, however, the role of it in the identification of viable myocardium in patients with chronic CAD has not yet been clarified. To determine the usefulness of rest-injected 99m Tc-MIBI scan as a marker of myocardial viability, the regional uptake of this agent at rest was compared with that of '2 01 T1 on reinjection and 24 hours after reinjection images. Subject patients were 13 chronic CAD patients who showed irreversible perfusion defect(s) on standard pharmacologic (dipyridamole) stress-redistribution images. Immediately after the redistribution images were obtained, 37 MBq thallium was injected at rest, and images were reacquired at 10 minutes and 24 hours after reinjection. After then 740 MBq 99m Tc-MIBI was injected, and 1 hour later rest MIBI myocardial imaging was performed. Five sets of images (stress, redistribution, reinjection, delayed images of thallium, and rest image of MIBI) were then analyzed qualitatively and quantitatively. Left ventricle was arbitrarily divided into 9 segments (apex, basal and apical portions of anterior, septal, inferior, and lateral walls). Seven patients and 30 regions showed a fixed perfusion defect on the stress-redistribution images. Among 30 regions, 15 showed positive uptakes and 6 showed negative uptakes on both 201 T1 reinjection/delayed images and 99m Tc-MIBI rest images. Five regions showed only thallium uptake and were regarded as viable clinically. Of four regions which showed only 99m Tc-MIBI uptake, two were regarded as viable, while the other two were regarded as a nonviable scar tissue clinically. In conclusion, 201 T1 reinjection technique was more reliable in the identification of viable myocardium. However, the role of 99m Tc-MIBI in identification of viable myocardium was still remained to be clarified because 2 of 9 regions showed only 99m Tc-MIBI uptake and were regarded as viable

Page Layout Analysis of the Document Image Based on the Region Classification in a Decision Hierarchical Structure

Directory of Open Access Journals (Sweden)

Hossein Pourghassem

2010-10-01

Full Text Available The conversion of document image to its electronic version is a very important problem in the saving, searching and retrieval application in the official automation system. For this purpose, analysis of the document image is necessary. In this paper, a hierarchical classification structure based on a two-stage segmentation algorithm is proposed. In this structure, image is segmented using the proposed two-stage segmentation algorithm. Then, the type of the image regions such as document and non-document image is determined using multiple classifiers in the hierarchical classification structure. The proposed segmentation algorithm uses two algorithms based on wavelet transform and thresholding. Texture features such as correlation, homogeneity and entropy that extracted from co-occurrenc matrix and also two new features based on wavelet transform are used to classifiy and lable the regions of the image. The hierarchical classifier is consisted of two Multilayer Perceptron (MLP classifiers and a Support Vector Machine (SVM classifier. The proposed algorithm is evaluated on a database consisting of document and non-document images that provides from Internet. The experimental results show the efficiency of the proposed approach in the region segmentation and classification. The proposed algorithm provides accuracy rate of 97.5% on classification of the regions.

Cine MR imaging assessment of regional left ventricular systolic wall thickening in patients with remote myocardial infarction

International Nuclear Information System (INIS)

Pfugfelder, P.; White, R.D.; Sechtem, U.; Gould, R.G.; Higgins, C.B.

1986-01-01

Cine MR imaging, a new rapid imaging technique, was used to acquire transverse images of the heart at a rate of 16-30 frames per cardiac cycle. Left ventricular wall thickness was measured at end diastole and end systole in six regions in the midventricular section of 13 healthy subjects and seven patients with previously documented myocardial infarction. Mean percent systolic wall thickening (%SWT) was 51% +- 26% in healthy subjects. In patients, %SWT was -8% +- 22% in the infarct zone and 42% +- 22% in the normal myocardium. In addition to the qualitative information derived from the cinematic display, determination of regional %SWT by cine-MR imaging may be useful for quantifying regional left ventricular dysfunction

High spatiotemporal resolution measurement of regional lung air volumes from 2D phase contrast x-ray images.

Science.gov (United States)

Leong, Andrew F T; Fouras, Andreas; Islam, M Sirajul; Wallace, Megan J; Hooper, Stuart B; Kitchen, Marcus J

2013-04-01

Described herein is a new technique for measuring regional lung air volumes from two-dimensional propagation-based phase contrast x-ray (PBI) images at very high spatial and temporal resolution. Phase contrast dramatically increases lung visibility and the outlined volumetric reconstruction technique quantifies dynamic changes in respiratory function. These methods can be used for assessing pulmonary disease and injury and for optimizing mechanical ventilation techniques for preterm infants using animal models. The volumetric reconstruction combines the algorithms of temporal subtraction and single image phase retrieval (SIPR) to isolate the image of the lungs from the thoracic cage in order to measure regional lung air volumes. The SIPR algorithm was used to recover the change in projected thickness of the lungs on a pixel-by-pixel basis (pixel dimensions ≈ 16.2 μm). The technique has been validated using numerical simulation and compared results of measuring regional lung air volumes with and without the use of temporal subtraction for removing the thoracic cage. To test this approach, a series of PBI images of newborn rabbit pups mechanically ventilated at different frequencies was employed. Regional lung air volumes measured from PBI images of newborn rabbit pups showed on average an improvement of at least 20% in 16% of pixels within the lungs in comparison to that measured without the use of temporal subtraction. The majority of pixels that showed an improvement was found to be in regions occupied by bone. Applying the volumetric technique to sequences of PBI images of newborn rabbit pups, it is shown that lung aeration at birth can be highly heterogeneous. This paper presents an image segmentation technique based on temporal subtraction that has successfully been used to isolate the lungs from PBI chest images, allowing the change in lung air volume to be measured over regions as small as the pixel size. Using this technique, it is possible to measure

Automatic detection of regions of interest in mammographic images

Science.gov (United States)

Cheng, Erkang; Ling, Haibin; Bakic, Predrag R.; Maidment, Andrew D. A.; Megalooikonomou, Vasileios

2011-03-01

This work is a part of our ongoing study aimed at comparing the topology of anatomical branching structures with the underlying image texture. Detection of regions of interest (ROIs) in clinical breast images serves as the first step in development of an automated system for image analysis and breast cancer diagnosis. In this paper, we have investigated machine learning approaches for the task of identifying ROIs with visible breast ductal trees in a given galactographic image. Specifically, we have developed boosting based framework using the AdaBoost algorithm in combination with Haar wavelet features for the ROI detection. Twenty-eight clinical galactograms with expert annotated ROIs were used for training. Positive samples were generated by resampling near the annotated ROIs, and negative samples were generated randomly by image decomposition. Each detected ROI candidate was given a confidences core. Candidate ROIs with spatial overlap were merged and their confidence scores combined. We have compared three strategies for elimination of false positives. The strategies differed in their approach to combining confidence scores by summation, averaging, or selecting the maximum score.. The strategies were compared based upon the spatial overlap with annotated ROIs. Using a 4-fold cross-validation with the annotated clinical galactographic images, the summation strategy showed the best performance with 75% detection rate. When combining the top two candidates, the selection of maximum score showed the best performance with 96% detection rate.

Improved phase sensitivity in spectral domain phase microscopy using line-field illumination and self phase-referencing

Science.gov (United States)

Yaqoob, Zahid; Choi, Wonshik; Oh, Seungeun; Lue, Niyom; Park, Yongkeun; Fang-Yen, Christopher; Dasari, Ramachandra R.; Badizadegan, Kamran; Feld, Michael S.

2010-01-01

We report a quantitative phase microscope based on spectral domain optical coherence tomography and line-field illumination. The line illumination allows self phase-referencing method to reject common-mode phase noise. The quantitative phase microscope also features a separate reference arm, permitting the use of high numerical aperture (NA > 1) microscope objectives for high resolution phase measurement at multiple points along the line of illumination. We demonstrate that the path-length sensitivity of the instrument can be as good as 41 pm/Hz, which makes it suitable for nanometer scale study of cell motility. We present the detection of natural motions of cell surface and two-dimensional surface profiling of a HeLa cell. PMID:19550464

Salient region detection by fusing bottom-up and top-down features extracted from a single image.

Science.gov (United States)

Tian, Huawei; Fang, Yuming; Zhao, Yao; Lin, Weisi; Ni, Rongrong; Zhu, Zhenfeng

2014-10-01

Recently, some global contrast-based salient region detection models have been proposed based on only the low-level feature of color. It is necessary to consider both color and orientation features to overcome their limitations, and thus improve the performance of salient region detection for images with low-contrast in color and high-contrast in orientation. In addition, the existing fusion methods for different feature maps, like the simple averaging method and the selective method, are not effective sufficiently. To overcome these limitations of existing salient region detection models, we propose a novel salient region model based on the bottom-up and top-down mechanisms: the color contrast and orientation contrast are adopted to calculate the bottom-up feature maps, while the top-down cue of depth-from-focus from the same single image is used to guide the generation of final salient regions, since depth-from-focus reflects the photographer's preference and knowledge of the task. A more general and effective fusion method is designed to combine the bottom-up feature maps. According to the degree-of-scattering and eccentricities of feature maps, the proposed fusion method can assign adaptive weights to different feature maps to reflect the confidence level of each feature map. The depth-from-focus of the image as a significant top-down feature for visual attention in the image is used to guide the salient regions during the fusion process; with its aid, the proposed fusion method can filter out the background and highlight salient regions for the image. Experimental results show that the proposed model outperforms the state-of-the-art models on three public available data sets.

Patient dose with quality image under diagnostic reference levels

International Nuclear Information System (INIS)

Akula, Suresh Kumar; Singh, Gurvinder; Chougule, Arun

2016-01-01

Need to set Diagnostic Reference Level (DRL) for locations for all diagnostic procedures in local as compared to National. The review of DRL's should compare local with national or referenced averages and a note made of any significant variances to these averages and the justification for it. To survey and asses radiation doses to patient and reduce the redundancy in patient imaging to maintain DRLs

Spatial Distribution Analysis of Soil Properties in Varzaneh Region of Isfahan Using Image Processing Techniques

Directory of Open Access Journals (Sweden)

F. Mahmoodi

2016-02-01

annual evaporation rate is 3265 mm. In this study, image processing techniquess including band combinations, Principal Component Analysis (PC1, PC2 and PC3, and classification were applied to a TM image to map different soil properties. In order to prepare the satellite image, geometric correction was performed. A 1:25,000 map (UTM 39 was used as a base to georegister the Landsat image. 40 Ground Control Points (GCPs were selected throughout the map and image. Road intersections or other man-made features were appropriate targets for this purpose. The raw image was transformed to the georectified image using a first order polynomial, and then resampled using the nearest neighbour method to preserve radiometry. The final Root Mean Square (RMS error for the selected points was 0.3 pixels. To establish relationships between image and field data, stratified random sampling techniques were used to collect 53 soil samples at the GPS (Global Positioning System points. The continuous map of soil properties was achieved using simple and multiple linear regression models by averaging 9 image pixels around sampling sites. Different image spectral indices were used as independent variables and the dependent variables were field- based data. Results and Discussion: The results of multiple regression analysis showed that the strongest relationships was between sandy soil and TM bands 1, 2, 3, 4, and 5, explaining up to 83% of variation in this component. The weakest relationship was found between CaCo3 and 3, 5, and 7 TM bands. In some cases, the multiple regressions was not an appropriate predicting model of soil properties, therefore, the TM and PC bands that had the highest relationship with field data (confidence level, 99% based on simple regression were classified by the maximum likelihood algorithm. According to error matrix, the overall accuracy of classified maps was between 85 and 93% for chlorine (Cl and silt componets, repectively. Conclusions: The results indicated that

Platforms for hyperspectral imaging, in-situ optical and acoustical imaging in urbanized regions

Science.gov (United States)

Bostater, Charles R.; Oney, Taylor

2016-10-01

Hyperspectral measurements of the water surface of urban coastal waters are presented. Oblique bidirectional reflectance factor imagery was acquired made in a turbid coastal sub estuary of the Indian River Lagoon, Florida and along coastal surf zone waters of the nearby Atlantic Ocean. Imagery was also collected using a pushbroom hyperspectral imager mounted on a fixed platform with a calibrated circular mechatronic rotation stage. Oblique imagery of the shoreline and subsurface features clearly shows subsurface bottom features and rip current features within the surf zone water column. In-situ hyperspectral optical signatures were acquired from a vessel as a function of depth to determine the attenuation spectrum in Palm Bay. A unique stationary platform methodology to acquire subsurface acoustic images showing the presence of moving bottom boundary nephelometric layers passing through the acoustic fan beam. The acoustic fan beam imagery indicated the presence of oscillatory subsurface waves in the urbanized coastal estuary. Hyperspectral imaging using the fixed platform techniques are being used to collect hyperspectral bidirectional reflectance factor (BRF) measurements from locations at buildings and bridges in order to provide new opportunities to advance our scientific understanding of aquatic environments in urbanized regions.

Our teacher likes you, so I like you: A social network approach to social referencing.

Science.gov (United States)

Hendrickx, Marloes M H G; Mainhard, Tim; Boor-Klip, Henrike J; Brekelmans, Mieke

2017-08-01

A teacher is a social referent for peer liking and disliking when students adjust their evaluations of a peer based on their perceptions of teacher liking and disliking for this peer. The present study investigated social referencing as an intra-individual process that occurs over time, using stochastic actor-oriented modeling with RSiena. The co-evolution of peer-perceived teacher liking and disliking networks with peer liking and disliking networks was analyzed in 52 fifth-grade classes in the Netherlands, with 1370 students (M age =10.60). Results showed that when a student viewed the teacher to like a peer, this student would also like this peer. Regarding disliking, there was a stronger effect in the opposite direction, indicating that students' disliking a peer increased the likelihood that they would view the peer as disliked by the teacher as well. In sum, partial evidence for social referencing as an intra-individual process was found. For teachers this implies that the cues they provide regarding their liking of a student, and not necessarily their disliking, may affect individual peers' liking of this student. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Image-converter diagnostics of laser and laser plasma in pico-femtosecond region

International Nuclear Information System (INIS)

Schelev, M.Ya.

1979-01-01

In the present communication we would like to outline some new trends in development of pico-femtosecond image-converter diagnostics for laser and laser plasma research on the basis of the recent works done in P.N.Lebedev Physical Institute. The discussion of the following subjects will be included: new generation of picosecond image-converter tubes (ICT), pulsed control circuitry, late prototype of picosecond image-converter cameras (ICC), test installation consisting of Nd: glass and YAG lasers for production the ultra-short pulses and sinusoidally modulated radiation, methods and techniques for image tube and camera dynamic measurements in IR, visible and X-ray spectral regions. Also discussed are the image processing technique for pictures taken with picosecond ICC in order to correct the geometrical distortions, enhance pictures quality and evaluate parameters of the input signals through their recorded images. (author)

MR imaging exploration of the pituitary region. Exploration IRM de l'axe hypothalamo-hypophysaire

Energy Technology Data Exchange (ETDEWEB)

Braun, M.; Roland, J. (Faculte de Medecine, 54 - Nancy (France)); Moret, C.; Picard, L. (Hopital Saint-Julien, 54 - Nancy (France))

1992-01-01

MR Imaging has become the procedure of choice for the exploration of the pituitary region. MR contrast resolution is far better than the finest CT examination, especially concerning the microadenomas and the neurohypophysis. The present paper concerns, at first the major principles of magnetic resonance imaging, its application for the study of the pituitary region including the use of contrast agent (Gadolinium). Lastly, MR anatomy and physiological variations are presented.

Imaging and detection of early stage dental caries with an all-optical photoacoustic microscope

International Nuclear Information System (INIS)

Hughes, D A; Kirk, K J; Sampathkumar, A; Longbottom, C

2015-01-01

Tooth decay, at its earliest stages, manifests itself as small, white, subsurface lesions in the enamel. Current methods for detection in the dental clinic are visual and tactile investigations, and bite-wing X-ray radiographs. These techniques suffer from poor sensitivity and specificity at the earliest (and reversible) stages of the disease due to the small size (<100μm) of the lesion. A fine-resolution (600 nm) ultra-broadband (200 MHz) all-optical photoacoustic microscopy system was is used to image the early signs of tooth decay. Ex-vivo tooth samples exhibiting white spot lesions were scanned and were found to generate a larger (one order of magnitude) photoacoustic (PA) signal in the lesion regions compared to healthy enamel. The high contrast in the PA images potentially allows lesions to be imaged and measured at a much earlier stage than current clinical techniques allow. PA images were cross referenced with histology photographs to validate our experimental results. Our PA system provides a noncontact method for early detection of white-spot lesions with a high detection bandwidth that offers advantages over previously demonstrated ultrasound methods. The technique provides the sensing depth of an ultrasound system, but with the spatial resolution of an optical system

10 CFR 170.21 - Schedule of fees for production and utilization facilities, review of standard referenced design...

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Schedule of fees for production and utilization facilities, review of standard referenced design approvals, special projects, inspections and import and export... AMENDED Schedule of Fees § 170.21 Schedule of fees for production and utilization facilities, review of...

A new analysis of archival images of comet 29P/Schwassmann-Wachmann 1 to constrain the rotation state of and active regions on its nucleus

Science.gov (United States)

Schambeau, C.; Fernández, Y.; Samarasinha, N.; Mueller, B.; Woodney, L.; Lisse, C.; Kelley, M.; Meech, K.

2014-07-01

Introduction: 29P/Schwassmann-Wachmann 1 (SW1) is a unique comet (and Centaur) with an almost circular orbit just outside the orbit of Jupiter. This orbit results in SW1 receiving a nearly constant insolation, thus giving a simpler environment in which to study thermal properties and behaviors of this comet's nucleus. Such knowledge is crucial for improving our understanding of coma morphology, nuclear thermal evolution, and nuclear structure. To this end, our overarching goal is to develop a thermophysical model of SW1's nucleus that makes use of realistic physical and structural properties as inputs. This model will help to explain the highly variable gas- and dust-production rates of this comet; SW1 is well known for its frequent but stochastic outbursts of mass loss [1,2,3]. Here we will report new constraints on the effective radius, beaming parameter, spin state, and location of active regions on the nucleus of SW1. Results: The analysis completed so far consists of a re-analysis of Spitzer Space Telescope thermal-IR images of SW1 from UT 2003 November 21 and 24, when SW1 was observed outside of outburst. The images are from Spitzer's IRAC 5.8-μm and 8.0-μm bands and MIPS 24.0-μm and 70-μm bands. This analysis is similar to that of Stansberry et al. [4, 5], but with data products generated from the latest Spitzer pipeline. Also, analysis of the 5.8-μm image had not been reported before. Coma removal techniques (e.g., Fernández et al. [6]) were applied to each image letting us measure the nuclear point-source contribution to each image. The measured flux densities for each band were fit with a Near Earth Asteroid Thermal Model (NEATM, [7]) and resulted in values for the effective radius of SW1's nucleus, constraints on the thermal inertia, and an IR beaming-parameter value. Current efforts have shifted to constraining the spin properties of SW1's nucleus and surface areas of activity through use of an existing Monte Carlo model [8, 9] to reproduce

Cardiac MRI: evaluation of phonocardiogram-gated cine imaging for the assessment of global und regional left ventricular function in clinical routine

International Nuclear Information System (INIS)

Nassenstein, Kai; Schlosser, Thomas; Orzada, Stephan; Haering, Lars; Czylwik, Andreas; Zenge, Michael; Mueller, Edgar; Eberle, Holger; Bruder, Oliver; Ladd, Mark E.; Maderwald, Stefan

2012-01-01

To validate a phonocardiogram (PCG)-gated cine imaging approach for the assessment of left ventricular (LV) function. In this prospective study, cine MR imaging of the LV was performed twice in 79 patients by using retrospectively PCG- and retrospectively ECG-gated cine SSFP sequences at 1.5 T. End-diastolic volumes (EDV), end-systolic volumes (ESV), stroke volumes (SV), ejection fraction (EF), muscle mass (MM), as well as regional wall motion were assessed. Subgroup analyses were performed for patients with valvular defects and for patients with dysrhythmia. PCG-gated imaging was feasible in 75 (95%) patients, ECG-gating in all patients. Excellent correlations were observed for all volumetric parameters (r > 0.98 for all variables analysed). No significant differences were observed for EDV (-0.24 ± 3.14 mL, P = 0.5133), ESV (-0.04 ± 2.36 mL, P = 0.8951), SV (-0.20 ± 3.41 mL, P = 0.6083), EF (-0.16 ± 1.98%, P = 0.4910), or MM (0.31 ± 4.2 g, P = 0.7067) for the entire study cohort, nor for either of the subgroups. PCG- and ECG-gated cine imaging revealed similar results for regional wall motion analyses (115 vs. 119 segments with wall motion abnormalities, P = 0.3652). The present study demonstrates that PCG-gated cine imaging enables accurate assessment of global and regional LV function in the vast majority of patients in clinical routine. (orig.)

Imaging a Time-variant Earthquake Focal Region along an Interplate Boundary

Science.gov (United States)

Tsuruga, K.; Kasahara, J.; Hasada, Y.; Fujii, N.

2010-12-01

We show a preliminary result of a trial for detecting a time-variant earthquake focal region along an interplate boundary by means of a new imaging method through a numerical simulation. Remarkable seismic reflections from the interplate boundaries of a subducting oceanic plate have been observed in Japan Trench (Mochizuki et al, 2005) and in Nankai Trough (Iidaka et al., 2003). Those strong seismic reflection existing in the current aseismic zones suggest the existence of fluid along the subduction boundary, and it is considered that they closely relate to a future huge earthquake. Seismic ACROSS has a potential to monitor some changes of transfer function along the propagating ray paths, by using an accurately-controlled transmission and receiving of the steady continuous signals repeatedly (Kumazawa et al., 2000). If the physical state in a focal region along the interplate would be changed enough in the time and space, for instance, by increasing or decreasing of fluid flow, we could detect some differences of the amplitude and/or travel-time of the particular reflection phases from the time-variant target region. In this study, we first investigated the seismic characteristics of seismograms and their differences before and after the change of a target region through a numerical simulation. Then, as one of the trials, we attempted to make an image of such time-variant target region by applying a finite-difference back-propagation technique in the time and space to the differences of waveforms (after Kasahara et al., 2010). We here used a 2-D seismic velocity model in the central Japan (Tsuruga et al., 2005), assuming a time-variant target region with a 200-m thickness along a subducting Philippine Sea plate at 30 km in depth. Seismograms were calculated at a 500-m interval for 260 km long by using FDM software (Larsen, 2000), in the case that P- and S-wave velocities (Vp amd Vs) in the target region decreased about 30 % before to after the change (e.g., Vp=3

Measurement of brain oxygenation changes using dynamic T1-weighted imaging

DEFF Research Database (Denmark)

Haddock, Bryan; Larsson, Henrik B W; Hansen, Adam E

2013-01-01

Magnetic resonance imaging (MRI) has proven useful in evaluating oxygenation in several types of tissue and blood. This study evaluates brain tissue oxygenation changes between normoxia and hyperoxia in healthy subjects using dynamic T1 and T2*-weighted imaging sequences. The change in FiO2 induced...... by hyperoxia caused a significant decrease in T1. A model to determine changes in tissue oxygen tension from the T1-weighted MRI signal is presented based on previous findings that T1 is sensitive to oxygen tension whereas T2* is sensitive to blood saturation. The two sequences produce results with different...... regional and temporal dynamics. These differences combined with results from simulations of the T1 signal intensities, indicate an increase in extravascular oxygen tension during hyperoxia. This study concludes that T1 and T2* responses to FiO2 serve as independent biomarkers of oxygen physiology...

Attenuation correction with region growing method used in the positron emission mammography imaging system

Science.gov (United States)

Gu, Xiao-Yue; Li, Lin; Yin, Peng-Fei; Yun, Ming-Kai; Chai, Pei; Huang, Xian-Chao; Sun, Xiao-Li; Wei, Long

2015-10-01

The Positron Emission Mammography imaging system (PEMi) provides a novel nuclear diagnosis method dedicated for breast imaging. With a better resolution than whole body PET, PEMi can detect millimeter-sized breast tumors. To address the requirement of semi-quantitative analysis with a radiotracer concentration map of the breast, a new attenuation correction method based on a three-dimensional seeded region growing image segmentation (3DSRG-AC) method has been developed. The method gives a 3D connected region as the segmentation result instead of image slices. The continuity property of the segmentation result makes this new method free of activity variation of breast tissues. The threshold value chosen is the key process for the segmentation method. The first valley in the grey level histogram of the reconstruction image is set as the lower threshold, which works well in clinical application. Results show that attenuation correction for PEMi improves the image quality and the quantitative accuracy of radioactivity distribution determination. Attenuation correction also improves the probability of detecting small and early breast tumors. Supported by Knowledge Innovation Project of The Chinese Academy of Sciences (KJCX2-EW-N06)

Active Contour Driven by Local Region Statistics and Maximum A Posteriori Probability for Medical Image Segmentation

Directory of Open Access Journals (Sweden)

Xiaoliang Jiang

2014-01-01

Full Text Available This paper presents a novel active contour model in a variational level set formulation for simultaneous segmentation and bias field estimation of medical images. An energy function is formulated based on improved Kullback-Leibler distance (KLD with likelihood ratio. According to the additive model of images with intensity inhomogeneity, we characterize the statistics of image intensities belonging to each different object in local regions as Gaussian distributions with different means and variances. Then, we use the Gaussian distribution with bias field as a local region descriptor in level set formulation for segmentation and bias field correction of the images with inhomogeneous intensities. Therefore, image segmentation and bias field estimation are simultaneously achieved by minimizing the level set formulation. Experimental results demonstrate desirable performance of the proposed method for different medical images with weak boundaries and noise.

Topoclimatic modeling for minimum temperature prediction at a regional scale in the Central Valley of Chile

International Nuclear Information System (INIS)

Santibáñez, F.; Morales, L.; Fuente, J. de la; Cellier, P.; Huete, A.

1997-01-01

Spring frost may strongly affect fruit production in the Central Valley of Chile. Minimum temperatures are spatially variable owing to topography and soil conditions. A methodology for forecasting minimum temperature at a regional scale in the Central Valley of Chile, integrating spatial variability of temperature under radiative frost conditions, has been developed. It uses simultaneously a model for forecasting minimum temperatures at a reference station using air temperature and humidity measured at 6 pm, and topoclimatic models, based on satellite infra-red imagery (NOAA/AVHRR) and a digital elevation model, to extend the prediction at a regional scale. The methodological developments were integrated in a geographic information system for geo referencing of a meteorological station with satellite imagery and modeled output. This approach proved to be a useful tool for short range (12 h) minimum temperature prediction by generating thermal images over the Central Valley of Chile. It may also be used as a tool for frost risk assessment, in order to adapt production to local climatological conditions. (author)

Utility of reconstructed image from 3-D MRI in the region of oral cavity

International Nuclear Information System (INIS)

Murakami, Shumei; Kakimoto, Naoya; Nakatani, Atsutoshi; Furuya, Shigeo; Furukawa, Shouhei; Fuchihata, Hajime

1998-01-01

The 3-D MRI with short TR was performed in the region of oral cavity, jaw and face, and utility of the reconstructed image was examined. Subjects were 8 healthy volunteers and 12 patients. The 3-D MRI was performed using SPGR with the following parameters; TR: 8 or 9 msec, TE: 2 or 3 msec, and FA: 20-30 degrees. Imaging direction was vertical to body axis. The matrix number was 256 x 192, slice thickness was 1 mm, slice interval was 0 and slice number was 128. The obtained image was reconstructed using software Reformat''. Detectability of temporomandibular joint disc was not enough in 8 of 20 cases. Detectability of mandibular canal was clear in 18 of 20 cases. In panorama MRI, soft tissue such as submandibular gland was detected. But, in hard tissue such as teeth or maxilla, there was a more little information in panorama MRI than in panorama X-ray photography. (K.H.)

A comparison of interest point and region detectors on structured, range and texture images

DEFF Research Database (Denmark)

Kazmi, Wajahat; Andersen, Hans Jørgen

2015-01-01

)) and corner based detectors (such as Hessian and Harris with both Affine/Laplace variants, SURF with determinant of Hessian based corners and SIFT with difference of Gaussians) acquired more than 90% mean average precision, whereas on range images, homogeneous region detector did not work well. TLR offered...... and textured images. It is also shown that in a bi-channel approach, combining surface and edge regions (MSER and TLR) boosts the overall performance. Among the descriptors, SIFT and SURF generally offer higher performance but low dimensional descriptors such as Steerable Filters follow closely....

Mobile TDR for geo-referenced measurement of soil water content and electrical conductivity

DEFF Research Database (Denmark)

Thomsen, Anton; Schelde, Kirsten; Drøscher, Per

2007-01-01

The development of site-specific crop management is constrained by the availability of sensors for monitoring important soil and crop related conditions. A mobile time-domain reflectometry (TDR) unit for geo-referenced soil measurements has been developed and used for detailed mapping of soil wat...... analysis of the soil water measurements, recommendations are made with respect to sampling strategies. Depending on the variability of a given area, between 15 and 30 ha can be mapped with respect to soil moisture and electrical conductivity with sufficient detail within 8 h...

Local region power spectrum-based unfocused ship detection method in synthetic aperture radar images

Science.gov (United States)

Wei, Xiangfei; Wang, Xiaoqing; Chong, Jinsong

2018-01-01

Ships on synthetic aperture radar (SAR) images will be severely defocused and their energy will disperse into numerous resolution cells under long SAR integration time. Therefore, the image intensity of ships is weak and sometimes even overwhelmed by sea clutter on SAR image. Consequently, it is hard to detect the ships from SAR intensity images. A ship detection method based on local region power spectrum of SAR complex image is proposed. Although the energies of the ships are dispersed on SAR intensity images, their spectral energies are rather concentrated or will cause the power spectra of local areas of SAR images to deviate from that of sea surface background. Therefore, the key idea of the proposed method is to detect ships via the power spectra distortion of local areas of SAR images. The local region power spectrum of a moving target on SAR image is analyzed and the way to obtain the detection threshold through the probability density function (pdf) of the power spectrum is illustrated. Numerical P- and L-band airborne SAR ocean data are utilized and the detection results are also illustrated. Results show that the proposed method can well detect the unfocused ships, with a detection rate of 93.6% and a false-alarm rate of 8.6%. Moreover, by comparing with some other algorithms, it indicates that the proposed method performs better under long SAR integration time. Finally, the applicability of the proposed method and the way of parameters selection are also discussed.

Microvax-based data management and reduction system for the regional planetary image facilities

Science.gov (United States)

Arvidson, R.; Guinness, E.; Slavney, S.; Weiss, B.

1987-01-01

Presented is a progress report for the Regional Planetary Image Facilities (RPIF) prototype image data management and reduction system being jointly implemented by Washington University and the USGS, Flagstaff. The system will consist of a MicroVAX with a high capacity (approx 300 megabyte) disk drive, a compact disk player, an image display buffer, a videodisk player, USGS image processing software, and SYSTEM 1032 - a commercial relational database management package. The USGS, Flagstaff, will transfer their image processing software including radiometric and geometric calibration routines, to the MicroVAX environment. Washington University will have primary responsibility for developing the database management aspects of the system and for integrating the various aspects into a working system.

A NEW REGION-BASED PDE FOR PERCEPTUAL IMAGE RESTORATION

OpenAIRE

Magnier , Baptiste; Montesinos , Philippe; Diep , Daniel

2012-01-01

International audience; In this paper, we present a new image regularization method using a rotating smoothing filter. The novelty of this approach resides in the mixing of ideas coming both from pixel classification which determines roughly if a pixel belongs to a homogenous region or an edge and an anisotropic perceptual edge detector which computes two precise diffusion directions. These directions are used by an anisotropic diffusion scheme. This anisotropic diffusion is accurately contro...

Combined preclinical magnetic particle imaging and magnetic resonance imaging. Initial results in mice

International Nuclear Information System (INIS)

Kaul, M.G.; Mummert, T.; Jung, C.; Raabe, N.; Ittrich, H.; Adam, G.; Heinen, U.; Reitmeier, A.

2015-01-01

Magnetic particle imaging (MPI) is a new radiologic imaging modality. For the first time, a commercial preclinical scanner is installed. The goal of this study was to establish a workflow between MPI and magnetic resonance imaging (MRI) scanners for a complete in vivo examination of a mouse and to generate the first co-registered in vivo MR-MP images. The in vivo examination of five mice were performed on a preclinical MPI scanner and a 7 Tesla preclinical MRI system. MRI measurements were used for anatomical referencing and validation of the injection of superparamagnetic iron oxide (SPIO) particles during a dynamic MPI scan. We extracted MPI data of the injection phase and co-registered it with MRI data. A workflow process for a combined in vivo MRI and MPI examination was established. A successful injection of ferucarbotran was proven in MPI and MRI. MR-MPI co-registration allocated the SPIOs in the inferior vena cava and the heart during and shortly after the injection. The acquisition of preclinical MPI and MRI data is feasible and allows the combined analysis of MR-MPI information.

Combined preclinical magnetic particle imaging and magnetic resonance imaging. Initial results in mice

Energy Technology Data Exchange (ETDEWEB)

Kaul, M.G.; Mummert, T.; Jung, C.; Raabe, N.; Ittrich, H.; Adam, G. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Diagnostic and Interventional Radiology; Weber, O. [Philips Medical Systems DMC GmbH, Hamburg (Germany); Heinen, U. [Bruker BioSpin MRI GmbH, Ettlingen (Germany); Reitmeier, A. [Medical Center Hamburg-Eppendorf, Hamburg (Germany). Animal Facility; Knopp, T. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Diagnostic and Interventional Radiology; Hamburg University of Technology, Hamburg (Germany)

2015-05-15

Magnetic particle imaging (MPI) is a new radiologic imaging modality. For the first time, a commercial preclinical scanner is installed. The goal of this study was to establish a workflow between MPI and magnetic resonance imaging (MRI) scanners for a complete in vivo examination of a mouse and to generate the first co-registered in vivo MR-MP images. The in vivo examination of five mice were performed on a preclinical MPI scanner and a 7 Tesla preclinical MRI system. MRI measurements were used for anatomical referencing and validation of the injection of superparamagnetic iron oxide (SPIO) particles during a dynamic MPI scan. We extracted MPI data of the injection phase and co-registered it with MRI data. A workflow process for a combined in vivo MRI and MPI examination was established. A successful injection of ferucarbotran was proven in MPI and MRI. MR-MPI co-registration allocated the SPIOs in the inferior vena cava and the heart during and shortly after the injection. The acquisition of preclinical MPI and MRI data is feasible and allows the combined analysis of MR-MPI information.

Reflex sympathetic dystrophy/complex regional pain syndrome, type 1

Directory of Open Access Journals (Sweden)

S.H. Botha

2004-06-01

Full Text Available Complex regional pain syndrome (CPRS, type 1 is a pain disorder that develops unpredictably and can follow a minor injury. A 12-year-old boy presented with severe pain in the feet and could not walk or stand weight bearing. Normal X-rays showed osteopenic changes and radiolucent lines, which appeared to be stress fractures. Three-phase bone scintigraphy showed no uptake in the left lower leg on the blood pool phase or on the immediate or delayed images. This indicated typical CPRS type 1 in children. The uptake in the right foot was increased and the stress fracture and other illness could not be differentiated. Computed tomography was done to exclude stress fractures. Only osteopenic changes in both calcaneus bones were found and there was no evidence of cortical stress fractures. Magnetic resonance images revealed oedema in the calcaneus and talus bones of both feet. The patient received epidural narcotic infusion with sympathetic blockage for 1 week combined with extensive physiotherapy. The blood pool phase of the bone scan became normal within 2 weeks, and increased uptake in both feet was noticed. The patient was followed up with MRI every 3 months and the bone marrow oedema disappeared after 6 months.

The Cost of Being Accountable: An Objective-Referenced Program Cost Model for Educational Management--A Maryland Perspective.

Science.gov (United States)

Holowenzak, Stephen P.; Stagmer, Robert A.

This publication describes in detail an objective-referenced program cost model for educational management that was developed by the Maryland State Department of Education. Primary purpose of the publication is to aid educational decision-makers in developing and refining their own method of cost-pricing educational programs for use in state and…

Description of a developmental criterion-referenced assessment for promoting competence in internal medicine residents.

Science.gov (United States)

Varney, Andrew; Todd, Christine; Hingle, Susan; Clark, Michael

2009-09-01

End-of- rotation global evaluations can be subjective, produce inflated grades, lack interrater reliability, and offer information that lacks value. This article outlines the generation of a unique developmental criterion-referenced assessment that applies adult learning theory and the learner, manager, teacher model, and represents an innovative application to the American Board of Internal Medicine (ABIM) 9-point scale. We describe the process used by Southern Illinois University School of Medicine to develop rotation-specific, criterion-based evaluation anchors that evolved into an effective faculty development exercise. The intervention gave faculty a clearer understanding of the 6 Accreditation Council for Graduate Medical Education competencies, each rotation's educational goals, and how rotation design affects meaningful work-based assessment. We also describe easily attainable successes in evaluation design and pitfalls that other institutions may be able to avoid. Shifting the evaluation emphasis on the residents' development of competence has made the expectations of rotation faculty more transparent, has facilitated conversations between program director and residents, and has improved the specificity of the tool for feedback. Our findings showed the new approach reduced grade inflation compared with the ABIM end-of-rotation global evaluation form. We offer the new developmental criterion-referenced assessment as a unique application of the competences to the ABIM 9-point scale as a transferable model for improving the validity and reliability of resident evaluations across graduate medical education programs.

H-1 MR spectroscopic imaging detects prolonged elevation of lactate and increased Ch/NAA ratio in patients with focal cerebral ischemia

International Nuclear Information System (INIS)

van Rijen, P.C.; Tulleken, C.A.F.; den Hollander, J.A.; Luyten, P.R.

1989-01-01

H-1 MR spectroscopy of patients with a recent stroke (range, 78 hours to 18 days after stroke) showed an increased Ch/NAA ratio in a large ischemic region of the brain, while lactate was increased in the center of the infarct. A spectroscopic image taken 8 months after the stroke did not show any increased lactate; however, the Ch/NAA ratio image still showed increased intensity even in regions that looked normal on the MR images. H-1 MR spectra measured during clinical recovery (range 10-48 days) still showed elevated lactate compared with control regions, although lactate was lower than in the acute phase. This suggests on ongoing anaerobic glycolysis in the metabolically compromised penumbra

Time course of NMR images and T1 values associated with hypertensive intracerebral hematoma

International Nuclear Information System (INIS)

Inao, Suguru; Furuse, Masahiro; Saso, Katsuyoshi; Yoshida, Kazuo; Motegi, Yoshimasa; Kaneoke, Yoshiki; Kamata, Noriko; Izawa, Akira

1986-01-01

The present study describes time courses in tissue T 1 values, as well as in NMR imagings, associated with hypertensive intracerebral hematoma (ICH). Non-operative 21 cases of ICH were examined by FONAR QED 80-α NMR system, which possessed dual modes of image display and focal T 1 measurement (static magnetic field : 433 gauss). As the first step of examination SSFP images are displayed and then, at the regions of interest, absolute values of T 1 are measured by field focusing technique. The extent of ICH was revealed as high density zone in NMR imaging, occasionally represented much wider extent of high density area than the finding on X-ray CT. Prolonged T 1 values were obtained from such high density zone. This widespread high density area was regarded to reflect the spread of perifocal brain edema. T 1 value of the hematoma itself was rather shortened in its initial phase within 2 weeks, thereafter followed by prolongation in the time lapse. This seemed to reflect the alterations in the properties of hematoma such as clot formation in earlier phase and resolution in later phase. On the contrary, T 1 in the brain tissue surrounded to hematoma was apparently prolonged in the early phase within 2 weeks, representing the maximal values of 312 msec arround 2 to 4 weeks after the onset, and then gradually normalized in the period over 1 month. This alteration in tissue T 1 likely represents the processes of edema formation and its regression in perifocal zone. T 1 values measured in perifocal region might be available for the evaluation of edema state in association with cerebrovascular accident. (author)

Handbook of mathematical methods in imaging

CERN Document Server

2015-01-01

The Handbook of Mathematical Methods in Imaging provides a comprehensive treatment of the mathematical techniques used in imaging science. The material is grouped into two central themes, namely, Inverse Problems (Algorithmic Reconstruction) and Signal and Image Processing. Each section within the themes covers applications (modeling), mathematics, numerical methods (using a case example) and open questions. Written by experts in the area, the presentation is mathematically rigorous. This expanded and revised second edition contains updates to existing chapters and 16 additional entries on important mathematical methods such as graph cuts, morphology, discrete geometry, PDEs, conformal methods, to name a few. The entries are cross-referenced for easy navigation through connected topics. Available in both print and electronic forms, the handbook is enhanced by more than 200 illustrations and an extended bibliography. It will benefit students, scientists and researchers in applied mathematics. Engineers and com...

A local region of interest image reconstruction via filtered backprojection for fan-beam differential phase-contrast computed tomography

International Nuclear Information System (INIS)

Qi Zhihua; Chen Guanghong

2007-01-01

Recently, x-ray differential phase contrast computed tomography (DPC-CT) has been experimentally implemented using a conventional source combined with several gratings. Images were reconstructed using a parallel-beam reconstruction formula. However, parallel-beam reconstruction formulae are not directly applicable for a large image object where the parallel-beam approximation fails. In this note, we present a new image reconstruction formula for fan-beam DPC-CT. There are two major features in this algorithm: (1) it enables the reconstruction of a local region of interest (ROI) using data acquired from an angular interval shorter than 180 0 + fan angle and (2) it still preserves the filtered backprojection structure. Numerical simulations have been conducted to validate the image reconstruction algorithm. (note)

Photoacoustic microscopy of complex regional pain syndrome type I (CRPS-1) after stellate ganglion blocks in vivo

Science.gov (United States)

Zhou, Yong; Yi, Xiaobin; Xing, Wenxin; Hu, Song; Maslov, Konstantin I.; Wang, Lihong V.

2015-03-01

We used photoacoustic microscopy (PAM) to assist diagnoses and monitor the progress and treatment outcome of complex regional pain syndrome type 1 (CRPS-1). Blood vasculature and oxygen saturation (sO2) were imaged by PAM in eight adult patients with CRPS-1. Patients' hands and cuticles were imaged both before and after stellate ganglion block (SGB) for comparison. For all patients, both the vascular structure and sO2 could be assessed by PAM. In addition, more vessels and stronger signals were observed after SGB.

Flexing and downsizing the femoral component is not detrimental to patellofemoral biomechanics in posterior-referencing cruciate-retaining total knee arthroplasty.

Science.gov (United States)

Marra, Marco A; Strzelczak, Marta; Heesterbeek, Petra J C; van de Groes, Sebastiaan A W; Janssen, Dennis; Koopman, Bart F J M; Verdonschot, Nico; Wymenga, Ate B

2018-03-20

When downsizing the femoral component to prevent mediolateral overhang, notching of the anterior femoral cortex may occur, which could be solved by flexing the femoral component. In this study, we investigated the effect of flexion of the femoral component on patellar tendon moment arm, patellofemoral forces and kinematics in posterior-referencing CR-TKA. Our hypothesis was that flexion of the femoral component increases the patellar tendon moment arm, reduces the patellofemoral forces and provides stable kinematics. A validated musculoskeletal model of CR-TKA was used. The flexion of the femoral component was increased in four steps (0°, 3°, 6°, 9°) using posterior referencing, and different alignments were analysed in combination with three implant sizes (3, 4, 5). A chair-rising trial was analysed using the model, while simultaneously estimating quadriceps muscle force, patellofemoral contact force, tibiofemoral and patellofemoral kinematics. Compared to the reference case (size 4 and 0° flexion), for every 3° of increase in flexion of the femoral component the patellar tendon moment arm increased by 1% at knee extension. The peak quadriceps muscle force and patellofemoral contact force decreased by 2%, the patella shifted 0.8 mm more anteriorly and the remaining kinematics remained stable, with knee flexion. With the smaller size, the patellar tendon moment arm decreased by 6%, the quadriceps muscle force and patellofemoral contact force increased by 8 and 12%, and the patellar shifted 5 mm more posteriorly. Opposite trends were found with the bigger size. Flexing the femoral component with posterior referencing reduced the patellofemoral contact forces during a simulated chair-rising trial with a patient-specific musculoskeletal model of CR-TKA. There seems to be little risk when flexing and downsizing the femoral component, compared to when using a bigger size and neutral alignment. These findings provide relevant information to surgeons who wish to

Roentgen signs in diagnostic imaging. Vol. 4/1: The chest. Pt. 1

International Nuclear Information System (INIS)

Meschan, I.; Farrer-Meschan, R.M.

1991-01-01

This first part of two of the volume on biomedical radiography of the thorax primarily deals with the roentgenography of the body regions and organs mentioned in the title augmentation. Chapters: Introduction. Patient positioning, projections, pathological findings, terminology. Chaper 1, Upper respiratory tract and lungs. Chapter 2, Radiography of the diaphragm, pleura, the osseous thorax, and the upper respiratory tract (excluding the larynx). Chapter 3, Mammography. Chapter 4, Laryngography. Chapter 5, Radiographic signs of pathological changes in the lungs - a survey. Chapter 6, Radiographic signs of respiratory illness in newborns, infants and children. Chapter 7, Unsharp, homogenous shadows in the lung parenchyma. Chapter 8, Roentgendiagnosis of round foci in the lung. Chapter 9, Linear and reticular lung shadows. Chapter 10, Diffuse and focal changes of the lung parenchyma with enhanced radiolucency. Non-roentgenographic imaging methods, such as CT, NMR imaging or nuclear medicine, are discussed only occasionally. (orig./MG) With 1590 figs., 61 tabs [de

Expanding the spectrum of human ganglionic eminence region anomalies on fetal magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Righini, Andrea; Parazzini, Cecilia; Izzo, Giana [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); Cesaretti, Claudia [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); Ospedale Maggiore Policlinico, Medical Genetics Unit, Fondazione I.R.C.C.S. Ca' Granda, Milan (Italy); Conte, Giorgio [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); University of Milan, Department of Health Sciences, Milan (Italy); Frassoni, Carolina; Inverardi, Francesca [Fondazione I.R.C.C.S. Istituto Neurologico ' ' C. Besta' ' , Clinical Epileptology and Experimental Neurophysiology Unit, Milan (Italy); Bulfamante, Gaetano; Avagliano, Laura [San Paolo Hospital, Division of Human Pathology, Milan (Italy); Rustico, Mariangela [Children' s Hospital ' ' V. Buzzi' ' , Department of Obstetrics and Gynaecology, Prenatal Diagnosis, Milan (Italy)

2016-03-15

Ganglionic eminence (GE) is a transient fetal brain structure that harvests a significant amount of precursors of cortical GABA-ergic interneurons. Prenatal magnetic resonance (MR) imaging features of GE anomalies (i.e., cavitations) have already been reported associated with severe micro-lissencephaly. The purpose of this report was to illustrate the MR imaging features of GE anomalies in conditions other than severe micro-lissencephalies. Among all the fetuses submitted to prenatal MR imaging at our center from 2005 to 2014, we collected eight cases with GE anomalies and only limited associated brain anomalies. The median gestational age at the time of MR imaging was 21 weeks ranging from 19 to 29 weeks. Two senior pediatric neuroradiologists categorized the anomalies of the GE region in two groups: group one showing cavitation in the GE region and group two showing enlarged GE region. For each fetal case, associated cranial anomalies were also reported. Five out of the eight cases were included in group one and three in group two. Besides the GE region abnormality, all eight cases had additional intracranial anomalies, such as mild partial callosal agenesis, vermian hypoplasia and rotation, cerebellar hypoplasia, ventriculomegaly, enlarged subarachnoid spaces, molar tooth malformation. Ultrasound generally detected most of the associated intracranial anomalies, prompting the MR investigation; on the contrary in none of the cases, GE anomalies had been detected by ultrasound. Our observation expands the spectrum of human GE anomalies, demonstrating that these may take place also without associated severe micro-lissencephalies. (orig.)

Expanding the spectrum of human ganglionic eminence region anomalies on fetal magnetic resonance imaging

International Nuclear Information System (INIS)

Righini, Andrea; Parazzini, Cecilia; Izzo, Giana; Cesaretti, Claudia; Conte, Giorgio; Frassoni, Carolina; Inverardi, Francesca; Bulfamante, Gaetano; Avagliano, Laura; Rustico, Mariangela

2016-01-01

Ganglionic eminence (GE) is a transient fetal brain structure that harvests a significant amount of precursors of cortical GABA-ergic interneurons. Prenatal magnetic resonance (MR) imaging features of GE anomalies (i.e., cavitations) have already been reported associated with severe micro-lissencephaly. The purpose of this report was to illustrate the MR imaging features of GE anomalies in conditions other than severe micro-lissencephalies. Among all the fetuses submitted to prenatal MR imaging at our center from 2005 to 2014, we collected eight cases with GE anomalies and only limited associated brain anomalies. The median gestational age at the time of MR imaging was 21 weeks ranging from 19 to 29 weeks. Two senior pediatric neuroradiologists categorized the anomalies of the GE region in two groups: group one showing cavitation in the GE region and group two showing enlarged GE region. For each fetal case, associated cranial anomalies were also reported. Five out of the eight cases were included in group one and three in group two. Besides the GE region abnormality, all eight cases had additional intracranial anomalies, such as mild partial callosal agenesis, vermian hypoplasia and rotation, cerebellar hypoplasia, ventriculomegaly, enlarged subarachnoid spaces, molar tooth malformation. Ultrasound generally detected most of the associated intracranial anomalies, prompting the MR investigation; on the contrary in none of the cases, GE anomalies had been detected by ultrasound. Our observation expands the spectrum of human GE anomalies, demonstrating that these may take place also without associated severe micro-lissencephalies. (orig.)

Social Referencing Gaze Behavior during a Videogame Task: Eye Tracking Evidence from Children with and without ASD

Science.gov (United States)

Finke, Erinn H.; Wilkinson, Krista M.; Hickerson, Benjamin D.

2017-01-01

The purpose of this study was to understand the social referencing behaviors of children with and without autism spectrum disorder (ASD) while visually attending to a videogame stimulus depicting both the face of the videogame player and the videogame play action. Videogames appear to offer a uniquely well-suited environment for the emergence of…

Broadband X-ray Imaging in the Near-Field Region of an Airblast Atomizer

Science.gov (United States)

Li, Danyu; Bothell, Julie; Morgan, Timothy; Heindel, Theodore

2017-11-01

The atomization process has a close connection to the efficiency of many spray applications. Examples include improved fuel atomization increasing the combustion efficiency of aircraft engines, or controlled droplet size and spray angle enhancing the quality and speed of the painting process. Therefore, it is vital to understand the physics of the atomization process, but the near-field region is typically optically dense and difficult to probe with laser-based or intrusive measurement techniques. In this project, broadband X-ray radiography and X-ray computed tomography (CT) imaging were performed in the near-field region of a canonical coaxial airblast atomizer. The X-ray absorption rate was enhanced by adding 20% by weight of Potassium Iodide to the liquid phase to increase image contrast. The radiographs provided an estimate of the liquid effective mean path length and spray angle at the nozzle exit for different flow conditions. The reconstructed CT images provided a 3D map of the time-average liquid spray distribution. X-ray imaging was used to quantify the changes in the near-field spray characteristics for various coaxial airblast atomizer flow conditions. Office of Naval Research.

Constraining reconnection region conditions using imaging and spectroscopic analysis of a coronal jet

Science.gov (United States)

Brannon, Sean; Kankelborg, Charles

2017-08-01

Coronal jets typically appear as thin, collimated structures in EUV and X-ray wavelengths, and are understood to be initiated by magnetic reconnection in the lower corona or upper chromosphere. Plasma that is heated and accelerated upward into coronal jets may therefore carry indirect information on conditions in the reconnection region and current sheet located at the jet base. On 2017 October 14, the Interface Region Imaging Spectrograph (IRIS) and Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA) observed a series of jet eruptions originating from NOAA AR 12599. The jet structure has a length-to-width ratio that exceeds 50, and remains remarkably straight throughout its evolution. Several times during the observation bright blobs of plasma are seen to erupt upward, ascending and subsequently descending along the structure. These blobs are cotemporal with footpoint and arcade brightenings, which we believe indicates multiple episodes of reconnection at the structure base. Through imaging and spectroscopic analysis of jet and footpoint plasma we determine a number of properties, including the line-of-sight inclination, the temperature and density structure, and lift-off velocities and accelerations of jet eruptions. We use these properties to constrain the geometry of the jet structure and conditions in reconnection region.

Myocardial imaging with 99mTc-Tetrofosmin: Influence of post-stress acquisition time, regional radiotracer uptake, and wall motion abnormalities on the clinical result.

Science.gov (United States)

Giorgetti, Assuero; Kusch, Annette; Casagranda, Mirta; Tagliavia, Irene D'Aragona; Marzullo, Paolo

2010-04-01

We previously demonstrated that early (15', T1) post-stress myocardial imaging with Tetrofosmin could be more accurate than standard acquisitions (45', T2) in identifying coronary artery disease. To clarify this phenomenon, 120 subjects (age 61 +/- 10 years) with both T1 and T2 scans were divided into Group 1 (53/120 pts) with more ischemia at T1 vs T2 imaging (T1-T2SDS > or = 3); Group 2 (67/120 pts) with similar results (T1-T2SDS statistic and semiquantitative wall motion/thickening values were obtained. Analysis of T1 and T2 post-stress myocardial counts demonstrated a significant Tetrofosmin wash-out rate that was higher in Group 1 control nonischemic regions (15 +/- 8% vs 13.6 +/- 9.6%, P stress wall thickening (T1-T2) was lower in Group 1 ischemic regions (-4.5 +/- 9.15% vs -1.90 +/- 7.0%, P stress acquisition time because of ischemic-induced regional wall thickening abnormalities and the existence of a differential radiotracer myocardial wash-out.

Atlas-based analysis of cardiac shape and function: correction of regional shape bias due to imaging protocol for population studies.

Science.gov (United States)

Medrano-Gracia, Pau; Cowan, Brett R; Bluemke, David A; Finn, J Paul; Kadish, Alan H; Lee, Daniel C; Lima, Joao A C; Suinesiaputra, Avan; Young, Alistair A

2013-09-13

Cardiovascular imaging studies generate a wealth of data which is typically used only for individual study endpoints. By pooling data from multiple sources, quantitative comparisons can be made of regional wall motion abnormalities between different cohorts, enabling reuse of valuable data. Atlas-based analysis provides precise quantification of shape and motion differences between disease groups and normal subjects. However, subtle shape differences may arise due to differences in imaging protocol between studies. A mathematical model describing regional wall motion and shape was used to establish a coordinate system registered to the cardiac anatomy. The atlas was applied to data contributed to the Cardiac Atlas Project from two independent studies which used different imaging protocols: steady state free precession (SSFP) and gradient recalled echo (GRE) cardiovascular magnetic resonance (CMR). Shape bias due to imaging protocol was corrected using an atlas-based transformation which was generated from a set of 46 volunteers who were imaged with both protocols. Shape bias between GRE and SSFP was regionally variable, and was effectively removed using the atlas-based transformation. Global mass and volume bias was also corrected by this method. Regional shape differences between cohorts were more statistically significant after removing regional artifacts due to imaging protocol bias. Bias arising from imaging protocol can be both global and regional in nature, and is effectively corrected using an atlas-based transformation, enabling direct comparison of regional wall motion abnormalities between cohorts acquired in separate studies.

Imagining School Autonomy in High-Performing Education Systems: East Asia as a Source of Policy Referencing in England

Science.gov (United States)

You, Yun; Morris, Paul

2016-01-01

Education reform is increasingly based on emulating the features of "world-class" systems that top international attainment surveys and, in England specifically, East Asia is referenced as the "inspiration" for their education reforms. However, the extent to which the features identified by the UK Government accord with the…

Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

Science.gov (United States)

Huang, Meiyan; Yang, Wei; Wu, Yao; Jiang, Jun; Gao, Yang; Chen, Yang; Feng, Qianjin; Chen, Wufan; Lu, Zhentai

2014-01-01

This study aims to develop content-based image retrieval (CBIR) system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR) images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW) model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML) is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor). Using the BoVW model with partition learning, the mean average precision (mAP) of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

Directory of Open Access Journals (Sweden)

Meiyan Huang

Full Text Available This study aims to develop content-based image retrieval (CBIR system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor. Using the BoVW model with partition learning, the mean average precision (mAP of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

Brain atlas for functional imaging. Clinical and research applications

International Nuclear Information System (INIS)

Nowinski, W.L.; Thirunavuukarasuu, A.; Kennedy, D.N

2001-01-01

This CD-ROM: Allows anatomical and functional images to be loaded and registered. Enables interactive placement of the Talairach landmarks in 3D Space. Provides automatic data-to-atlas warping based on the Talairaich proportional gridsystem transformation. Real-time interactive warping for fine tuning is also available. Allows the user to place marks on the activation loci in the warped functional images, display these marks with the atlas, and edit them in three planes. Mark placement is assisted by image thresholding. Provides simultaneous display of the atlas, anatomical image and functional image within one interactively blended image. Atlas-data blending and anatomical-functional image blending are controlled independently. Labels the data by means of the atlas. The atlas can be flipped left/right so that Brodmann's areas and gyri can be labeled on both hemispheres. Provides additional functions such as friendly navigation, cross-referenced display, readout of the Talairach coordinates and intensities, load coordinates, save, on-line help. (orig.)

Brain atlas for functional imaging. Clinical and research applications

Energy Technology Data Exchange (ETDEWEB)

Nowinski, W.L.; Thirunavuukarasuu, A.; Kennedy, D.N

2001-07-01

This CD-ROM: Allows anatomical and functional images to be loaded and registered. Enables interactive placement of the Talairach landmarks in 3D Space. Provides automatic data-to-atlas warping based on the Talairaich proportional gridsystem transformation. Real-time interactive warping for fine tuning is also available. Allows the user to place marks on the activation loci in the warped functional images, display these marks with the atlas, and edit them in three planes. Mark placement is assisted by image thresholding. Provides simultaneous display of the atlas, anatomical image and functional image within one interactively blended image. Atlas-data blending and anatomical-functional image blending are controlled independently. Labels the data by means of the atlas. The atlas can be flipped left/right so that Brodmann's areas and gyri can be labeled on both hemispheres. Provides additional functions such as friendly navigation, cross-referenced display, readout of the Talairach coordinates and intensities, load coordinates, save, on-line help. (orig.)

A Novel Histogram Region Merging Based Multithreshold Segmentation Algorithm for MR Brain Images

Directory of Open Access Journals (Sweden)

Siyan Liu

2017-01-01

Full Text Available Multithreshold segmentation algorithm is time-consuming, and the time complexity will increase exponentially with the increase of thresholds. In order to reduce the time complexity, a novel multithreshold segmentation algorithm is proposed in this paper. First, all gray levels are used as thresholds, so the histogram of the original image is divided into 256 small regions, and each region corresponds to one gray level. Then, two adjacent regions are merged in each iteration by a new designed scheme, and a threshold is removed each time. To improve the accuracy of the merger operation, variance and probability are used as energy. No matter how many the thresholds are, the time complexity of the algorithm is stable at O(L. Finally, the experiment is conducted on many MR brain images to verify the performance of the proposed algorithm. Experiment results show that our method can reduce the running time effectively and obtain segmentation results with high accuracy.

Passive Forensics for Region Duplication Image Forgery Based on Harris Feature Points and Local Binary Patterns

Directory of Open Access Journals (Sweden)

Jie Zhao

2013-01-01

Full Text Available Nowadays the demand for identifying the authenticity of an image is much increased since advanced image editing software packages are widely used. Region duplication forgery is one of the most common and immediate tampering attacks which are frequently used. Several methods to expose this forgery have been developed to detect and locate the tampered region, while most methods do fail when the duplicated region undergoes rotation or flipping before being pasted. In this paper, an efficient method based on Harris feature points and local binary patterns is proposed. First, the image is filtered with a pixelwise adaptive Wiener method, and then dense Harris feature points are employed in order to obtain a sufficient number of feature points with approximately uniform distribution. Feature vectors for a circle patch around each feature point are extracted using local binary pattern operators, and the similar Harris points are matched based on their representation feature vectors using the BBF algorithm. Finally, RANSAC algorithm is employed to eliminate the possible erroneous matches. Experiment results demonstrate that the proposed method can effectively detect region duplication forgery, even when an image was distorted by rotation, flipping, blurring, AWGN, JPEG compression, and their mixed operations, especially resistant to the forgery with the flat area of little visual structures.

Increased native T1-values at the interventricular insertion regions in precapillary pulmonary hypertension.

Science.gov (United States)

Spruijt, Onno A; Vissers, Loek; Bogaard, Harm-Jan; Hofman, Mark B M; Vonk-Noordegraaf, Anton; Marcus, J Tim

2016-03-01

Cardiac magnetic resonance imaging of the pressure overloaded right ventricle (RV) of precapillary pulmonary hypertension (PH) patients, exhibits late gadolinium enhancement at the interventricular insertion regions, a phenomenon which has been linked to focal fibrosis. Native T1-mapping is an alternative technique to characterize myocardium and has the advantage of not requiring the use of contrast agents. The aim of this study was to characterize the myocardium of idiopathic pulmonary arterial hypertension (IPAH), systemic scleroderma related PH (PAH-Ssc) and chronic thromboembolic PH (CTEPH) patients using native T1-mapping and to see whether native T1-values were related to disease severity. Furthermore, we compared native T1-values between the different precapillary PH categories. Native T1-mapping was performed in 46 IPAH, 14 PAH-SSc and 10 CTEPH patients and 10 control subjects. Native T1-values were assessed using regions of interest at the RV and LV free wall, interventricular septum and interventricular insertion regions. In PH patients, native T1-values of the interventricular insertion regions were significantly higher than the native T1-values of the RV free wall, LV free wall and interventricular septum. Native T1-values at the insertion regions were significantly related to disease severity. Native T1-values were not different between IPAH, PAH-Ssc and CTEPH patients. Native T1-values of the interventricular insertion regions are significantly increased in precapillary PH and are related to disease severity. Native T1-mapping can be developed as an alternative technique for the characterization of the interventricular insertion regions and has the advantage of not requiring the use of contrast agents.

A Brief "DSM-IV"-Referenced Teacher Rating Scale for Monitoring Behavioral Improvement in ADHD and Co-Occurring Symptoms

Science.gov (United States)

Sprafkin, Joyce; Mattison, Richard E.; Gadow, Kenneth D.; Schneider, Jayne; Lavigne, John V.

2011-01-01

Objective: To examine the psychometric properties of the 30-item teacher's version of the Child and Adolescent Symptom Inventory Progress Monitor (CASI-PM-T), a "DSM-IV"-referenced rating scale for monitoring change in ADHD and co-occurring symptoms in youths receiving behavioral or pharmacological interventions. Method: Three separate studies…

Webcam network and image database for studies of phenological changes of vegetation and snow cover in Finland, image time series from 2014 to 2016

Science.gov (United States)

Peltoniemi, Mikko; Aurela, Mika; Böttcher, Kristin; Kolari, Pasi; Loehr, John; Karhu, Jouni; Linkosalmi, Maiju; Melih Tanis, Cemal; Tuovinen, Juha-Pekka; Nadir Arslan, Ali

2018-01-01

In recent years, monitoring of the status of ecosystems using low-cost web (IP) or time lapse cameras has received wide interest. With broad spatial coverage and high temporal resolution, networked cameras can provide information about snow cover and vegetation status, serve as ground truths to Earth observations and be useful for gap-filling of cloudy areas in Earth observation time series. Networked cameras can also play an important role in supplementing laborious phenological field surveys and citizen science projects, which also suffer from observer-dependent observation bias. We established a network of digital surveillance cameras for automated monitoring of phenological activity of vegetation and snow cover in the boreal ecosystems of Finland. Cameras were mounted at 14 sites, each site having 1-3 cameras. Here, we document the network, basic camera information and access to images in the permanent data repository (http://www.zenodo.org/communities/phenology_camera/). Individual DOI-referenced image time series consist of half-hourly images collected between 2014 and 2016 (https://doi.org/10.5281/zenodo.1066862). Additionally, we present an example of a colour index time series derived from images from two contrasting sites.

Webcam network and image database for studies of phenological changes of vegetation and snow cover in Finland, image time series from 2014 to 2016

Directory of Open Access Journals (Sweden)

M. Peltoniemi

2018-01-01

Full Text Available In recent years, monitoring of the status of ecosystems using low-cost web (IP or time lapse cameras has received wide interest. With broad spatial coverage and high temporal resolution, networked cameras can provide information about snow cover and vegetation status, serve as ground truths to Earth observations and be useful for gap-filling of cloudy areas in Earth observation time series. Networked cameras can also play an important role in supplementing laborious phenological field surveys and citizen science projects, which also suffer from observer-dependent observation bias. We established a network of digital surveillance cameras for automated monitoring of phenological activity of vegetation and snow cover in the boreal ecosystems of Finland. Cameras were mounted at 14 sites, each site having 1–3 cameras. Here, we document the network, basic camera information and access to images in the permanent data repository (http://www.zenodo.org/communities/phenology_camera/. Individual DOI-referenced image time series consist of half-hourly images collected between 2014 and 2016 (https://doi.org/10.5281/zenodo.1066862. Additionally, we present an example of a colour index time series derived from images from two contrasting sites.

Rapid detection of hypoxia-inducible factor-1-active tumours: pretargeted imaging with a protein degrading in a mechanism similar to hypoxia-inducible factor-1{alpha}

Energy Technology Data Exchange (ETDEWEB)

Ueda, Masashi [Kyoto University, Radioisotopes Research Laboratory, Kyoto University Hospital, Faculty of Medicine, Kyoto (Japan); Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kudo, Takashi; Konishi, Hiroaki; Miyano, Azusa; Ono, Masahiro; Saji, Hideo [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kuge, Yuji [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan); Mukai, Takahiro [Kyushu University, Department of Biomolecular Recognition Chemistry, Graduate School of Pharmaceutical Sciences, Fukuoka (Japan); Tanaka, Shotaro; Kizaka-Kondoh, Shinae; Hiraoka, Masahiro [Kyoto University, Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto (Japan)

2010-08-15

Hypoxia-inducible factor-1 (HIF-1) plays an important role in malignant tumour progression. For the imaging of HIF-1-active tumours, we previously developed a protein, POS, which is effectively delivered to and selectively stabilized in HIF-1-active cells, and a radioiodinated biotin derivative, (3-{sup 123}I-iodobenzoyl)norbiotinamide ({sup 123}I-IBB), which can bind to the streptavidin moiety of POS. In this study, we aimed to investigate the feasibility of the pretargeting method using POS and {sup 123}I-IBB for rapid imaging of HIF-1-active tumours. Tumour-implanted mice were pretargeted with POS. After 24 h, {sup 125}I-IBB was administered and subsequently, the biodistribution of radioactivity was investigated at several time points. In vivo planar imaging, comparison between {sup 125}I-IBB accumulation and HIF-1 transcriptional activity, and autoradiography were performed at 6 h after the administration of {sup 125}I-IBB. The same sections that were used in autoradiographic analysis were subjected to HIF-1{alpha} immunohistochemistry. {sup 125}I-IBB accumulation was observed in tumours of mice pretargeted with POS (1.6%ID/g at 6 h). This result is comparable to the data derived from {sup 125}I-IBB-conjugated POS-treated mice (1.4%ID/g at 24 h). In vivo planar imaging provided clear tumour images. The tumoral accumulation of {sup 125}I-IBB significantly correlated with HIF-1-dependent luciferase bioluminescence (R=0.84, p<0.01). The intratumoral distribution of {sup 125}I-IBB was heterogeneous and was significantly correlated with HIF-1{alpha}-positive regions (R=0.58, p<0.0001). POS pretargeting with {sup 123}I-IBB is a useful technique in the rapid imaging and detection of HIF-1-active regions in tumours. (orig.)

Automatic delineation of brain regions on MRI and PET images from the pig.

Science.gov (United States)

Villadsen, Jonas; Hansen, Hanne D; Jørgensen, Louise M; Keller, Sune H; Andersen, Flemming L; Petersen, Ida N; Knudsen, Gitte M; Svarer, Claus

2018-01-15

The increasing use of the pig as a research model in neuroimaging requires standardized processing tools. For example, extraction of regional dynamic time series from brain PET images requires parcellation procedures that benefit from being automated. Manual inter-modality spatial normalization to a MRI atlas is operator-dependent, time-consuming, and can be inaccurate with lack of cortical radiotracer binding or skull uptake. A parcellated PET template that allows for automatic spatial normalization to PET images of any radiotracer. MRI and [ 11 C]Cimbi-36 PET scans obtained in sixteen pigs made the basis for the atlas. The high resolution MRI scans allowed for creation of an accurately averaged MRI template. By aligning the within-subject PET scans to their MRI counterparts, an averaged PET template was created in the same space. We developed an automatic procedure for spatial normalization of the averaged PET template to new PET images and hereby facilitated transfer of the atlas regional parcellation. Evaluation of the automatic spatial normalization procedure found the median voxel displacement to be 0.22±0.08mm using the MRI template with individual MRI images and 0.92±0.26mm using the PET template with individual [ 11 C]Cimbi-36 PET images. We tested the automatic procedure by assessing eleven PET radiotracers with different kinetics and spatial distributions by using perfusion-weighted images of early PET time frames. We here present an automatic procedure for accurate and reproducible spatial normalization and parcellation of pig PET images of any radiotracer with reasonable blood-brain barrier penetration. Copyright © 2017 Elsevier B.V. All rights reserved.

Problems forming innovative-technological image of russian regions