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Sample records for activity retriever evar

  1. A vision architecture for the extravehicular activity retriever

    NASA Technical Reports Server (NTRS)

    Magee, Michael

    1992-01-01

    The Extravehicular Activity Retriever (EVAR) is a robotic device currently being developed by the Automation and Robotics Division at the NASA Johnson Space Center to support activities in the neighborhood of the Space Shuttle or Space Station Freedom. As the name implies, the Retriever's primary function will be to provide the capability to retrieve tools, equipment or other objects which have become detached from the spacecraft, but it will also be able to rescue a crew member who may have become inadvertently de-tethered. Later goals will include cooperative operations between a crew member and the Retriever such as fetching a tool that is required for servicing or maintenance operations. This report documents a preliminary design for a Vision System Planner (VSP) for the EVAR that is capable of achieving visual objectives provided to it by a high level task planner. Typical commands which the task planner might issue to the VSP relate to object recognition, object location determination, and obstacle detection. Upon receiving a command from the task planner, the VSP then plans a sequence of actions to achieve the specified objective using a model-based reasoning approach. This sequence may involve choosing an appropriate sensor, selecting an algorithm to process the data, reorienting the sensor, adjusting the effective resolution of the image using lens zooming capability, and/or requesting the task planner to reposition the EVAR to obtain a different view of the object. An initial version of the Vision System Planner which realizes the above capabilities using simulated images has been implemented and tested. The remaining sections describe the architecture and capabilities of the VSP and its relationship to the high level task planner. In addition, typical plans that are generated to achieve visual goals for various scenarios will be discussed. Specific topics to be addressed will include object search strategies, repositioning of the EVAR to improve the

  2. A vision system planner for increasing the autonomy of the Extravehicular Activity Helper/Retriever

    NASA Technical Reports Server (NTRS)

    Magee, Michael

    1993-01-01

    The Extravehicular Activity Retriever (EVAR) is a robotic device currently being developed by the Automation and Robotics Division at the NASA Johnson Space Center to support activities in the neighborhood of the Space Shuttle or Space Station Freedom. As the name implies, the Retriever's primary function will be to provide the capability to retrieve tools and equipment or other objects which have become detached from the spacecraft, but it will also be able to rescue a crew member who may have become inadvertently de-tethered. Later goals will include cooperative operations between a crew member and the Retriever such as fetching a tool that is required for servicing or maintenance operations. This paper documents a preliminary design for a Vision System Planner (VSP) for the EVAR that is capable of achieving visual objectives provided to it by a high level task planner. Typical commands which the task planner might issue to the VSP relate to object recognition, object location determination, and obstacle detection. Upon receiving a command from the task planner, the VSP then plans a sequence of actions to achieve the specified objective using a model-based reasoning approach. This sequence may involve choosing an appropriate sensor, selecting an algorithm to process the data, reorienting the sensor, adjusting the effective resolution of the image using lens zooming capability, and/or requesting the task planner to reposition the EVAR to obtain a different view of the object. An initial version of the Vision System Planner which realizes the above capabilities using simulated images has been implemented and tested. The remaining sections describe the architecture and capabilities of the VSP and its relationship to the high level task planner. In addition, typical plans that are generated to achieve visual goals for various scenarios are discussed. Specific topics to be addressed will include object search strategies, repositioning of the EVAR to improve the

  3. The astronaut and the banana peel: An EVA retriever scenario

    NASA Technical Reports Server (NTRS)

    Shapiro, Daniel G.

    1989-01-01

    To prepare for the problem of accidents in Space Station activities, the Extravehicular Activity Retriever (EVAR) robot is being constructed, whose purpose is to retrieve astronauts and tools that float free of the Space Station. Advanced Decision Systems is at the beginning of a project to develop research software capable of guiding EVAR through the retrieval process. This involves addressing problems in machine vision, dexterous manipulation, real time construction of programs via speech input, and reactive execution of plans despite the mishaps and unexpected conditions that arise in uncontrolled domains. The problem analysis phase of this work is presented. An EVAR scenario is used to elucidate major domain and technical problems. An overview of the technical approach to prototyping an EVAR system is also presented.

  4. Smart hands for the EVA retriever

    NASA Technical Reports Server (NTRS)

    Hess, Clifford W.; Li, Larry C.

    1990-01-01

    Dexterous, robotic hands are required for the extravehicular activity retriever (EVAR) system being developed by the NASA Johnson Space Center (JSC). These hands, as part of the EVAR system, must be able to grasp objects autonomously and securely which inadvertently separate from the Space Station. Development of the required hands was initiated in 1987. Outlined here are the hand development activities, including design considerations, progress to date, and future plans. Several types of dexterous hands that were evaluated, along with a proximity-sensing capability that was developed to initiate a reflexive, adaptive grasp, are described. The evaluations resulted in the design and fabrication of a 6-degree-of-freedom (DOF) hand that has two fingers and a thumb arranged in an anthropomorphic configuration. Finger joint force and position sensors are included in the design, as well as infrared proximity sensors which allow initiation of the grasp sequence when an object is detected within the grasp envelope.

  5. Effortful retrieval reduces hippocampal activity and impairs incidental encoding.

    PubMed

    Reas, Emilie T; Brewer, James B

    2013-05-01

    Functional imaging studies frequently report that the hippocampus is engaged by successful episodic memory retrieval. However, considering that concurrent encoding of the background environment occurs during retrieval and influences medial temporal lobe activity, it is plausible that hippocampal encoding functions are reduced with increased attentional engagement during effortful retrieval. Expanding upon evidence that retrieval efforts suppress activity in hippocampal regions implicated in encoding, this study examines the influence of retrieval effort on encoding performance and the interactive effects of encoding and retrieval on hippocampal and neocortical activity. Functional magnetic resonance imaging was conducted while subjects performed a word recognition task with incidental picture encoding. Both lower memory strength and increased search duration were associated with encoding failure and reduced hippocampal and default network activity. Activity in the anterior hippocampus tracked encoding, which was more strongly deactivated when incidental encoding was unsuccessful. These findings highlight potential contributions from background encoding processes to hippocampal activations during neuroimaging studies of episodic memory retrieval. PMID:23378272

  6. Activities of information retrieval in Daicel Corporation : The roles and efforts of information retrieval team

    NASA Astrophysics Data System (ADS)

    Yamazaki, Towako

    In order to stabilize and improve quality of information retrieval service, the information retrieval team of Daicel Corporation has given some efforts on standard operating procedures, interview sheet for information retrieval, structured format for search report, and search expressions for some technological fields of Daicel. These activities and efforts will also lead to skill sharing and skill tradition between searchers. In addition, skill improvements are needed not only for a searcher individually, but also for the information retrieval team totally when playing searcher's new roles.

  7. Dissociating retrieval success from incidental encoding activity during emotional memory retrieval, in the medial temporal lobe

    PubMed Central

    Shafer, Andrea T.; Dolcos, Florin

    2014-01-01

    The memory-enhancing effect of emotion has been linked to the engagement of emotion- and memory-related medial temporal lobe (MTL) regions (amygdala-AMY; hippocampus-HC; parahippocampus-PHC), during both encoding and retrieval. However, recognition tasks used to investigate the neural correlates of retrieval make it difficult to distinguish MTL engagement linked to retrieval success (RS) from that linked to incidental encoding success (ES) during retrieval. This issue has been investigated for retrieval of non-emotional memories, but not for emotional memory retrieval. To address this, we used event-related functional MRI in conjunction with an emotional distraction and two episodic memory tasks (one testing memory for distracter items and the other testing memory for new/lure items presented in the first memory task). This paradigm allowed for dissociation of MTL activity specifically linked to RS from that linked to both RS and incidental ES during retrieval. There were two novel findings regarding the neural correlates of emotional memory retrieval. First, greater emotional RS was identified bilaterally in AMY, HC, and PHC. However, AMY activity was most impacted when accounting for ES activity, as only RS activity in left AMY was dissociated from ES activity during retrieval, whereas portions of HC and PHC showing greater emotional RS were largely uninvolved in ES. Second, an earlier and more anteriorly spread response (left AMY and bilateral HC, PHC) was linked to greater emotional RS activity, whereas a later and more posteriorly localized response (right posterior PHC) was linked to greater neutral RS activity. These findings shed light on MTL mechanisms subserving the memory-enhancing effect of emotion at retrieval. PMID:24917798

  8. Active index for content-based medical image retrieval.

    PubMed

    Chang, S K

    1996-01-01

    This paper introduces the active index for content-based medical image retrieval. The dynamic nature of the active index is its most important characteristic. With an active index, we can effectively and efficiently handle smart images that respond to accessing, probing and other actions. The main applications of the active index are to prefetch image and multimedia data, and to facilitate similarity retrieval. The experimental active index system is described. PMID:8954230

  9. Can Surgeons Assess CT Suitability for Endovascular Repair (EVAR) in Ruptured Abdominal Aortic Aneurysm? Implications for a Ruptured EVAR Trial

    SciTech Connect

    Rayt, Harjeet Lambert, Kelly; Bown, Matthew; Fishwick, Guy; Morgan, Robert; McCarthy, Mark; London, Nick; Sayers, Robert

    2008-09-15

    The purpose of this study was to determine whether surgeons without formal radiological training are able to assess suitability of patients with ruptured abdominal aortic aneurysms (AAA) for EVAR. The CT scans of 20 patients with AAA were reviewed under timed conditions by six vascular surgeons. Twenty minutes was allocated per scan. They were asked to determine if each aneurysm would be treatable by EVAR in the emergency setting and, if so, to measure for device selection. The results were then compared with those of a vascular radiologist. Six surgeons agreed on the suitability of endovascular repair in 45% of cases (95% CI, 23.1-68.5%; 9/20 scans; {kappa} = 0.41 [p = 0.01]) and concurred with the radiologist in eight of these. Individually, agreement ranged from 13 to 16 of the 20 scans, 65-80% between surgeons. The kappa value for agreement between all the surgeons and the radiologist was 0.47 (p = 0.01, moderate agreement). For the individual surgeons, this ranged from 0.3 to 0.6 (p = 0.01). In conclusion, while overall agreement was moderate between the surgeons and the radiologist, it is clear that if surgeons are to assess patients for ruptured EVAR in the future, focused training of surgical trainees is required.

  10. Endovascular Aneurysm Repair and Sealing (EVARS): A Useful Adjunct in Treating Challenging Morphology.

    PubMed

    Harrison, Gareth J; Antoniou, George A; Torella, Francesco; McWilliams, Richard G; Fisher, Robert K

    2016-04-01

    An 81-year-old male with previous open abdominal aortic aneurysm repair presented with asymptomatic large pseudoaneurysms at both ends of an open surgical tube graft. Endovascular aneurysm sealing (EVAS) in combination with the iliac limbs of a standard endovascular aneurysm repair (EVAR) successfully excluded both pseudoaneurysms from circulation. We describe the combination of elements of EVAS and EVAR and have termed this endovascular aneurysm repair and sealing (EVARS). EVARS has the advantage of harnessing the benefits of endobag sealing in aortic necks unsuitable for standard EVAR whilst providing the security of accurate stent placement within short common iliac arteries. In conclusion, EVAS may be combined with standard endovascular iliac limbs and is a possible treatment option for pseudoaneurysm following open aneurysm repair. PMID:26493819

  11. Ultra-low profile Ovation device: is it the definitive solution for EVAR?

    PubMed

    de Donato, G; Setacci, F; Sirignano, P; Galzerano, G; Borrelli, M P; di Marzo, L; Setacci, C

    2014-02-01

    When Juan Parodi implanted an endograft in a human body for the first time on September 7, 1990 in Buenos Aires, Argentina, the delivery system of the handmade device was primitive, extremely rigid, and had a bulky profile of 27 French (F). Since then, stent-graft technology has evolved rapidly, limitations of earlier-generation devices have been overtaken, and endovascular aneurysm repair (EVAR) eligibility has increased enormously. Nevertheless (still) challenging aortoiliac anatomy such as short and complex proximal aortic neck seal zones and narrow access vessels are responsible for EVAR ineligibility in up to 50% of cases. The Ovation Prime abdominal stent-graft system (TriVascular, Inc., Santa Rosa, CA, USA) is a trimodular device designed with the aortic body delivered via a flexible, hydrophilic-coated, ultra-low profile catheter (14-F outer diameter - OD). The aortic body is provided with a suprarenal nitinol stent with anchors that provide active fixation, while a network of rings and channels that are inflated with a low-viscosity radiopaque polymer during stent-graft deployment, provides effective sealing. The previous EVAR technology aimed to both anchor and seal using stents combined with fabric, with neither optimized for their roles and each forced to compete for the same space within their delivery catheters, which inevitably led to larger profile of the delivery system. The technical revolution of the Ovation endograft includes the idea to truly uncouple the stages of stent-graft fixation and seal during the procedure. In the Ovation endograft platform, stent and fabric are not competing the same space within the delivery system and an ultra-low profile delivery can be achieved without compromise. With such a low-profile delivery catheter, approximately 90% of men and 70% of women with abdominal aortic aneurysm have access vessel diameters considered fit for endovascular repair. The aim of this review paper was to analyze the main properties of

  12. Brain activity underlying encoding and retrieval of source memory.

    PubMed

    Cansino, Selene; Maquet, Pierre; Dolan, Raymond J; Rugg, Michael D

    2002-10-01

    Neural activity elicited during the encoding and retrieval of source information was investigated with event-related functional magnetic resonance imaging (efMRI). During encoding, 17 subjects performed a natural/artificial judgement on pictures of common objects which were presented randomly in one of the four quadrants of the display. At retrieval, old pictures were mixed with new ones and subjects judged whether each picture was new or old and, if old, indicated in which quadrant it was presented at encoding. During encoding, study items that were later recognized and assigned a correct source judgement elicited greater activity than recognized items given incorrect judgements in a variety of regions, including right lateral occipital and left prefrontal cortex. At retrieval, regions showing greater activity for recognized items given correct versus incorrect source judgements included the right hippocampal formation and the left prefrontal cortex. These findings indicate a role for these regions in the encoding and retrieval of episodic information beyond that required for simple item recognition. PMID:12217968

  13. Muscular Activity in the Arm during Lexical Retrieval: Implications for Gesture-Speech Theories

    ERIC Educational Resources Information Center

    Morsella, Ezequiel; Krauss, Robert M.

    2005-01-01

    The origin and functions of the hand and arm gestures that accompany speech production are poorly understood. It has been proposed that gestures facilitate lexical retrieval, but little is known about when retrieval is accompanied by gestural activity and how this activity is related to the semantics of the word to be retrieved. Electromyographic…

  14. Binding among Select Episodic Elements Is Altered via Active Short-Term Retrieval

    ERIC Educational Resources Information Center

    Bridge, Donna J.; Voss, Joel L.

    2015-01-01

    Of the many elements that comprise an episode, are any disproportionately bound to the others? We tested whether active short-term retrieval selectively increases binding. Individual objects from multiobject displays were retrieved after brief delays. Memory was later tested for the other objects. Cueing with actively retrieved objects facilitated…

  15. Colorectal cancer associated with abdominal aortic aneurysm: results of EVAR followed by colectomy.

    PubMed

    Illuminati, Giulio; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

    2013-01-01

    The association of colorectal cancer and abdominal aortic aneurysm (AAA) is infrequent but poses special problems of priority of treatment under elective circumstances. The purpose of this study was to retrospectively evaluate the outcome of 16 consecutive patients undergoing endovascular aneurysm repair (EVAR) followed by colectomy. Operative mortality was nil. Operative morbidity included two transient rise of serum creatinine level and one extraperitoneal anastomotic leakage which evolved favourably with conservative treatment. EVAR allowed a very short delay of treatment of colorectal cancer after aneurysm repair, minimizing operative complications. PMID:23151840

  16. Type 2 Endoleaks Post-EVAR: Current Evidence for Rupture Risk, Intervention and Outcomes of Treatment

    SciTech Connect

    Chung, Raymond Morgan, Robert A.

    2015-06-15

    Type 2 endoleaks (EL2) are the most commonly encountered endoleaks following EVAR. Despite two decades of experience, there remains considerable variation in the management of EL2 with controversies ranging from if to treat, when to treat and how to treat. Here, we summarise the available evidence, describe the treatment techniques available and offer guidelines for management.

  17. Retrieving Binary Answers Using Whole-Brain Activity Pattern Classification

    PubMed Central

    Nawa, Norberto E.; Ando, Hiroshi

    2015-01-01

    Multivariate pattern analysis (MVPA) has been successfully employed to advance our understanding of where and how information regarding different mental states is represented in the human brain, bringing new insights into how these states come to fruition, and providing a promising complement to the mass-univariate approach. Here, we employed MVPA to classify whole-brain activity patterns occurring in single fMRI scans, in order to retrieve binary answers from experiment participants. Five healthy volunteers performed two types of mental task while in the MRI scanner: counting down numbers and recalling positive autobiographical events. Data from these runs were used to train individual machine learning based classifiers that predicted which mental task was being performed based on the voxel-based brain activity patterns. On a different day, the same volunteers reentered the scanner and listened to six statements (e.g., “the month you were born is an odd number”), and were told to countdown numbers if the statement was true (yes) or recall positive events otherwise (no). The previously trained classifiers were then used to assign labels (yes/no) to the scans collected during the 24-second response periods following each one of the statements. Mean classification accuracies at the single scan level were in the range of 73.6 to 80.8%, significantly above chance for all participants. When applying a majority vote on the scans within each response period, i.e., the most frequent label (yes/no) in the response period becomes the answer to the previous statement, 5.0 to 5.8 sentences, out of 6, were correctly classified in each one of the runs, on average. These results indicate that binary answers can be retrieved from whole-brain activity patterns, suggesting that MVPA provides an alternative way to establish basic communication with unresponsive patients when other techniques are not successful. PMID:26778992

  18. Assimilation of Passive and Active Microwave Soil Moisture Retrievals

    NASA Technical Reports Server (NTRS)

    Draper, C. S.; Reichle, R. H.; DeLannoy, G. J. M.; Liu, Q.

    2012-01-01

    Root-zone soil moisture is an important control over the partition of land surface energy and moisture, and the assimilation of remotely sensed near-surface soil moisture has been shown to improve model profile soil moisture [1]. To date, efforts to assimilate remotely sensed near-surface soil moisture at large scales have focused on soil moisture derived from the passive microwave Advanced Microwave Scanning Radiometer (AMSR-E) and the active Advanced Scatterometer (ASCAT; together with its predecessor on the European Remote Sensing satellites (ERS. The assimilation of passive and active microwave soil moisture observations has not yet been directly compared, and so this study compares the impact of assimilating ASCAT and AMSR-E soil moisture data, both separately and together. Since the soil moisture retrieval skill from active and passive microwave data is thought to differ according to surface characteristics [2], the impact of each assimilation on the model soil moisture skill is assessed according to land cover type, by comparison to in situ soil moisture observations.

  19. Large, colorful, or noisy? Attribute- and modality-specific activations during retrieval of perceptual attribute knowledge.

    PubMed

    Kellenbach, M L; Brett, M; Patterson, K

    2001-09-01

    Position emission tomography was used to investigate whether retrieval of perceptual knowledge from long-term memory activates unique cortical regions associated with the modality and/or attribute type retrieved. Knowledge about the typical color, size, and sound of common objects and animals was probed, in response to written words naming the objects. Relative to a nonsemantic control task, all the attribute judgments activated similar left temporal and frontal regions. Visual (color, size) knowledge selectively activated the right posterior inferior temporal (PIT) cortex, whereas sound judgments elicited selective activation in the left posterior superior temporal gyrus and the adjacent parietal cortex. All of the attribute judgments activated a left PIT region, but color retrieval generated more activation in this area. Size judgments activated the right medial parietal cortex. These results indicate that the retrieval of perceptual semantic information activates not only a general semantic network, but also cortical areas specialized for the modality and attribute type of the knowledge retrieved. PMID:12467121

  20. Autobiographical Memory Retrieval and Hippocampal Activation as a Function of Repetition and the Passage of Time

    PubMed Central

    Nadel, Lynn; Campbell, Jenna; Ryan, Lee

    2007-01-01

    Multiple trace theory (MTT) predicts that hippocampal memory traces expand and strengthen as a function of repeated memory retrievals. We tested this hypothesis utilizing fMRI, comparing the effect of memory retrieval versus the mere passage of time on hippocampal activation. While undergoing fMRI scanning, participants retrieved remote autobiographical memories that had been previously retrieved either one month earlier, two days earlier, or multiple times during the preceding month. Behavioral analyses revealed that the number and consistency of memory details retrieved increased with multiple retrievals but not with the passage of time. While all three retrieval conditions activated a similar set of brain regions normally associated with autobiographical memory retrieval including medial temporal lobe structures, hippocampal activation did not change as a function of either multiple retrievals or the passage of time. However, activation in other brain regions, including the precuneus, lateral prefrontal cortex, parietal cortex, lateral temporal lobe, and perirhinal cortex increased after multiple retrievals, but was not influenced by the passage of time. These results have important implications for existing theories of long-term memory consolidation. PMID:18274617

  1. Percutaneous Retrieval of a Radiolucent Foreign Body from an EVAR Device by Combining Different Image Modalities

    SciTech Connect

    Barbiero, Giulio; Cognolato, Diego; Polverosi, Roberta; Guarise, Alessandro

    2009-07-15

    Percutaneous extraction techniques are an established method for removing endovascular foreign bodies. Generally, the foreign body to be removed is radiopaque (i.e., catheter and guidewire fragments, vena cava filters, embolization coils, endovascular stents). We propose an application of these techniques to remove a radiolucent foreign body (i.e., pigtail cover) by means of a combination of different imaging techniques (fluoroscopy, digital subtraction angiography, ultrasound, and computed axial tomography).

  2. Development of Active Control within Working Memory: Active Retrieval versus Monitoring in Children

    ERIC Educational Resources Information Center

    Blain-Brière, Bénédicte; Bouchard, Caroline; Bigras, Nathalie; Cadoret, Geneviève

    2014-01-01

    This study aimed to compare children's performance on two mnemonic functions that engage the lateral prefrontal cortex. Brain imaging studies in adults have shown that the mid-ventrolateral prefrontal cortex is specifically involved in active controlled retrieval, and the mid-dorsolateral prefrontal cortex is specifically involved in…

  3. Mapping Neuronal Activation and the Influence of Adrenergic Signaling during Contextual Memory Retrieval

    ERIC Educational Resources Information Center

    Zhang, Wei-Ping; Guzowski, John F.; Thomas, Steven A.

    2005-01-01

    We recently described a critical role for adrenergic signaling in the hippocampus during contextual and spatial memory retrieval. To determine which neurons are activated by contextual memory retrieval and its sequelae in the presence and absence of adrenergic signaling, transcriptional imaging for the immediate-early gene "Arc" was used in…

  4. Critical analysis of results after chimney EVAR raises cause for concern

    PubMed Central

    Scali, Salvatore T.; Feezor, Robert J.; Chang, Catherine K.; Waterman, Alyson L.; Berceli, Scott A.; Huber, Thomas S.; Beck, Adam W.

    2014-01-01

    Objective Chimney” techniques used to extend landing zones for endovascular aortic repair(chEVAR) have been increasingly reported; however, concerns about durability and patency remain. The purpose of this analysis was to examine mid-term outcomes of chEVAR. Methods All patients at the University of Florida treated with chEVAR were reviewed. Major adverse events(MAEs) were recorded and defined as any chimney stent thrombosis, type 1a endoleak in follow-up, reintervention, 30-day/in-hospital death and/or ≥ 25% decrease in estimated glomerular filtration rate after discharge. Primary end-points included chimney stent patency and freedom from MAE. Secondary end-points included complications and long-term survival. Results From 2008–2012, 41 patients[age ± standard deviation(SD); 73±8; male 66%(N=27)] were treated with a total of 76 chimney stents(renal, N=51; superior mesenteric artery, N=16 celiac artery, N=9) for a variety of indications: juxtarenal, 42%(N=17, 1 rupture); suprarenal, 17%(N=7), and thoracoabdominal aneurysm, 17%(N=7); aortic anastomotic pseudoaneurysm, 15%(N=6; 3 ruptures), type 1a endoleak after EVAR, 7%(N=3), and atheromatous disease, 2%(N=1). Two patients had a single target vessel abandoned due to cannulation failure and one had a type 1a endoleak at case completion(technical success = 93%). Intraoperative complications occurred in 7 patients(17%), including graft maldeployment with unplanned mesenteric chimney(N=2) and access vessel injury requiring repair(N=5). Major postoperative complications developed in 20%(N=8). 30-day and in-hospital mortality were 5%(N=2) and 7%(N=3), respectively. At median follow-up of 18.2(range 1.4–41.5) months, 28 of 33(85%) patients with available postoperative imaging experienced stabilization or reduction of AAA sac diameters. Nine(32%) patients developed endoleak at some point during follow-up [type 1a, 7%(N=3); type 2, 10%(N=4); indeterminate, 7%(N=3)], and one patient underwent open, surgical

  5. Hippocampal Activation during Episodic and Semantic Memory Retrieval: Comparing Category Production and Category Cued Recall

    PubMed Central

    Ryan, Lee; Cox, Christine; Hayes, Scott M.; Nadel, Lynn

    2008-01-01

    Whether or not the hippocampus participates in semantic memory retrieval has been the focus of much debate in the literature. However, few neuroimaging studies have directly compared hippocampal activation during semantic and episodic retrieval tasks that are well matched in all respects other than the source of the retrieved information. In Experiment 1, we compared hippocampal fMRI activation during a classic semantic memory task, category production, and an episodic version of the same task, category cued recall. Left hippocampal activation was observed in both episodic and semantic conditions, although other regions of the brain clearly distinguished the two tasks. Interestingly, participants reported using retrieval strategies during the semantic retrieval task that relied on autobiographical and spatial information; for example, visualizing themselves in their kitchen while producing items for the category kitchen utensils. In Experiment 2, we considered whether the use of these spatial and autobiographical retrieval strategies could have accounted for the hippocampal activation observed in Experiment 1. Categories were presented that elicited one of three retrieval strategy types, autobiographical and spatial, autobiographical and nonspatial, and neither autobiographical nor spatial. Once again, similar hippocampal activation was observed for all three category types, regardless of the inclusion of spatial or autobiographical content. We conclude that the distinction between semantic and episodic memory is more complex than classic memory models suggest. PMID:18420234

  6. Morphological State as a Predictor for Reintervention and Mortality After EVAR for AAA

    SciTech Connect

    Ohrlander, Tomas; Dencker, Magnus; Acosta, Stefan

    2012-10-15

    Purpose: This study was designed to assess aorto-iliac morphological characteristics in relation to reintervention and all-cause long-term mortality in patients undergoing standard EVAR for infrarenal AAA. Methods: Patients treated with EVAR (Zenith{sup Registered-Sign} Stentgrafts, Cook) between May 1998 and February 2006 were prospectively enrolled in a computerized database where comorbidities and preoperative aneurysm morphology were entered. Reinterventions and mortality were checked until December 1, 2010. Median follow-up time was 68 months. Results: A total of 304 patients were included, of which 86% were men. Median age was 74 years. The reintervention rate was 23.4% (71/304). A greater diameter of the common iliac artery (p = 0.037; hazard ratio (HR) 1.037 [1.002-1.073]) was an independent factor for an increased number of reinterventions. The 30-day mortality rate was 3.0% (9/304). Aneurysm-related deaths due to AAA occurred in 4.9% (15/304). Five patients died due to a concomitant ruptured thoracic aortic aneurysm. The mortality until end of follow-up was 54.3% (165/304). The proportion of deaths caused by vascular diseases was 61.6%. The severity of angulation of the iliac arteries (p = 0.014; HR 1.018 [95% confidence interval (CI) 1.004-1.033]) and anemia (p = 0.044; HR 2.79 [95% CI 1.029-7.556]) remained as independent factors associated with all-cause long-term mortality. The crude reintervention-free survival rate at 1, 3, and 5 years was 84.5%, 64.8%, and 51.6%, respectively. Conclusions: The initial aorto-iliac morphological state in patients scheduled for standard EVAR for AAA seems to be strongly related to the need for reinterventions and long-term mortality.

  7. Endovascular Aortic Aneurysm and Dissection Repair (EVAR) in Iran: Descriptive Midterm Follow-up Results

    PubMed Central

    Haji Zeinali, Ali Mohammad; Marzban, Mehrab; Zafarghandi, Mohammadreza; Shirzad, Mahmood; Shirani, Shapour; Mahmoodian, Roshanak; Sheikhvatan, Mehrdad; Lotfi-Tokaldany, Masoumeh

    2016-01-01

    Background: Endovascular repair of aorta in comparison to open surgery has a low early operative mortality rate, but its long-term results are uncertain. Objectives: The current study describes for the first time our initial four-year experience of elective endovascular aortic repair (EVAR) at Tehran heart center, the first and a major referral heart center in Iran, as a pioneer of EVAR in Iran. Patients and Methods: A total of 51 patients (46 men) who had the diagnosis of either an abdominal aortic aneurysm (AAA) (n = 36), thoracic aortic aneurysm (TAA) (n = 7), or thoracic aortic dissection (TAD) (n = 8) who had undergone EVAR by Medtronic stent grafts by our team between December 2006 and June 2009 were reviewed. Results: The rate of in-hospital aneurysm-related deaths in the group with AAA stood at 2.8% (one case), while there was no in-hospital mortality in the other groups. All patients were followed up for 13-18 months. The cumulative death rate in follow-up was nine cases from the total 51 cases (18%), out of which six cases were in the AAA group (four patients due to non-cardiac causes and two patients due to aneurysm-related causes), one case in the TAA group (following a severe hemoptysis), and two cases in the TAD group (following an expansion of dissection from re-entrance). The major event-free survival rate was 80.7% for endovascular repair of AAA, 85.7% for endovascular repair of TAA, and 65.6% for endovascular repair of TAD. Conclusion: The endovascular stent-graft repair of the abdominal and thoracic aortic aneurysm and aortic dissection had high technical success rates in tandem with low-rate early mortality and morbidity, short hospital stay, and acceptable mid-term free symptom survival among Iranian patients. PMID:27110330

  8. How Safe is Bilateral Internal Iliac Artery Embolization Prior to EVAR?

    SciTech Connect

    Bratby, M. J. Munneke, G. M.; Belli, A.-M.; Loosemore, T. M.; Loftus, I.; Thompson, M. M.; Morgan, R. A.

    2008-03-15

    Purpose. To assess the outcomes of patients after bilateral internal iliac artery (IIA) embolization prior to endovascular aneurysm repair (EVAR). Methods. Thirty-nine patients (age range 55-88 years, mean 72.5 years; 2 women) underwent IIA embolization/occlusion before EVAR. There were 28 patients with aorto-biiliac aneurysms and 6 with bilateral common iliac artery (CIA) aneurysms. Five patients with unilateral CIA aneurysms had previous surgical ligation of the contralateral IIA or inadvertent covering by the stent-graft of the contralateral IIA origin. Outcomes were assessed by clinical follow-up. Results. Severe ischemic complications were limited to spinal cord ischemia in 1 patient (3%) who developed paraparesis following EVAR. No other severe ischemic complications such as buttock necrosis, or bowel or bladder ischemia, occurred. Buttock and/or thigh claudication occurred in 12 patients (31%) and persisted beyond 1 year in 3 patients (9%). Sexual dysfunction occurred in 2 patients (5%). Patients who underwent simultaneous embolization had a 25% (3/12) ischemic complication rate versus 41% (11/27) in those with sequential embolization (p = 0.48). Embolization limited to the main trunk of the IIA resulted in a significantly reduced ischemic complication rate of 16% (3/19) versus 55% (11/20) of patients who had a more distal embolization of the IIA (p = 0.019, Fisher's exact test). Conclusion. Severe complications after bilateral IIA embolization are uncommon. Although buttock/thigh claudication occurs in around 30% of patients soon after the procedure, this resolves in the majority after 1 year. There is no obvious benefit for sequential versus simultaneous IIA embolization in our series. Occlusion of the proximal IIA trunk is associated with reduced complications compared with occlusion of the distal IIA.

  9. Overview of the Tank Focus Area HLW Tank Retrieval Activities (Remote Operations)

    SciTech Connect

    GIBBONS, P.W.

    2001-01-01

    Several U.S. Department of Energy (DOE) sites are currently retrieving or preparing to retrieve radioactive waste from underground storage tanks with technical assistance from the Tanks Focus Area. The Tanks Focus Area is a national program that provides information and technologies to safely and effectively remediate radioactive waste stored in DOE's underground tanks. Funding for the Tanks Focus Area is provided by the DOE Offices of Science and Technology, Environmental Restoration, and Waste Management. This paper provides an overview of recent remote waste retrieval activities as well as recent successes sponsored by the Tanks Focus Area.

  10. A Timely Intervention: Endoscopic Retrieval of a Swallowed Magnetized Activity Watch

    PubMed Central

    Radowsky, Jason S.; Lee, Joseph S.; Schlussel, Andrew T.

    2016-01-01

    The accidental ingestion of a foreign object often presents a difficult scenario for the clinician. This includes not only the decision to retrieve the material but also the appropriate technique to use. We present the case of a young asymptomatic girl who swallowed a magnetic activity watch, which was then successfully retrieved with an endoscopic snare. To our knowledge, this is the first documented case of salvaging an operational watch from the stomach using an endoscopic technique. PMID:26904319

  11. A Timely Intervention: Endoscopic Retrieval of a Swallowed Magnetized Activity Watch.

    PubMed

    Radowsky, Jason S; Lee, Joseph S; Schlussel, Andrew T

    2016-01-01

    The accidental ingestion of a foreign object often presents a difficult scenario for the clinician. This includes not only the decision to retrieve the material but also the appropriate technique to use. We present the case of a young asymptomatic girl who swallowed a magnetic activity watch, which was then successfully retrieved with an endoscopic snare. To our knowledge, this is the first documented case of salvaging an operational watch from the stomach using an endoscopic technique. PMID:26904319

  12. Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)

    SciTech Connect

    Lagana, Domenico Mangini, Monica Fontana, Federico; Nicotera, Paolo; Carrafiello, Gianpaolo; Fugazzola, Carlo

    2009-01-15

    The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed tomography (MDCT) showed a retroperitoneal hematoma; in both cases a type III endoleak was detected, in one case associated with a type II endoleak from the iliolumbar artery. The procedures were performed in the theater, in emergency. Type II endoleak was treated with transcatheter superselective glue injection; type III endoleaks were excluded by a stent-graft extension. The procedures were successful in both patients, with immediate hemodynamic stabilization. MDCT after the procedure showed complete exclusion of the aneurysms. In conclusion, endovascular treatment is a safe and feasible option for the treatment of ruptured AAAs previously treated by EVAR; this approach allows avoidance of surgical conversion, which is technical very challenging, with a high morbidity and mortality rate.

  13. Influencing Factors for Abdominal Aortic Aneurysm Sac Shrinkage and Enlargement after EVAR: Clinical Reviews before Introduction of Preoperative Coil Embolization

    PubMed Central

    Hiraoka, Arudo; Totsugawa, Toshinori; Tamura, Kentaro; Ishida, Atsuhisa; Sakaguchi, Taichi; Yoshitaka, Hidenori

    2014-01-01

    Background: We previously reported effectiveness of coil embolization (CE) to aortic branched vessels before endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) because of significant shrinkage of aneurysmal sac. In this study, we investigated EVAR cases to clarify influential factors of aneurysmal shrinkage and enlargement. Methods: 148 consecutive cases before the introduction of CE were retrospectively reviewed based on the presence of PT2EL (persistent type 2 endoleak) and change in sac diameter after EVAR by multivariate analysis. Results: (A) PT2EL risk factors were patent inferior mesenteric artery (IMA) and thinner mural thrombus inside aneurysmal sac. (B) Sac enlargement risk factors were antiplatelet intake, PT2EL, and female gender. (C) Sac shrinkage predictive factors were the absences of thoracic aortic aneurysm, antiplatelet intake, PT2EL, and coronary artery disease. Conclusion: CE to IMA was considered to be effective because patent IMA and antiplatelet intake were significant risk factors for sac enlargement. So, more meticulous therapeutic strategy, including treatment priority (AAA first or CAD first) and choice of treatment (EVAR vs. AAA) based on anatomical features of AAA was required to improve late outcomes. PMID:25298830

  14. Brain region-specific activity patterns after recent or remote memory retrieval of auditory conditioned fear.

    PubMed

    Kwon, Jeong-Tae; Jhang, Jinho; Kim, Hyung-Su; Lee, Sujin; Han, Jin-Hee

    2012-01-01

    Memory is thought to be sparsely encoded throughout multiple brain regions forming unique memory trace. Although evidence has established that the amygdala is a key brain site for memory storage and retrieval of auditory conditioned fear memory, it remains elusive whether the auditory brain regions may be involved in fear memory storage or retrieval. To investigate this possibility, we systematically imaged the brain activity patterns in the lateral amygdala, MGm/PIN, and AuV/TeA using activity-dependent induction of immediate early gene zif268 after recent and remote memory retrieval of auditory conditioned fear. Consistent with the critical role of the amygdala in fear memory, the zif268 activity in the lateral amygdala was significantly increased after both recent and remote memory retrieval. Interesting, however, the density of zif268 (+) neurons in both MGm/PIN and AuV/TeA, particularly in layers IV and VI, was increased only after remote but not recent fear memory retrieval compared to control groups. Further analysis of zif268 signals in AuV/TeA revealed that conditioned tone induced stronger zif268 induction compared to familiar tone in each individual zif268 (+) neuron after recent memory retrieval. Taken together, our results support that the lateral amygdala is a key brain site for permanent fear memory storage and suggest that MGm/PIN and AuV/TeA might play a role for remote memory storage or retrieval of auditory conditioned fear, or, alternatively, that these auditory brain regions might have a different way of processing for familiar or conditioned tone information at recent and remote time phases. PMID:22993170

  15. Goal- and retrieval-dependent activity in the striatum during memory recognition.

    PubMed

    Clos, Mareike; Schwarze, Ulrike; Gluth, Sebastian; Bunzeck, Nico; Sommer, Tobias

    2015-06-01

    The striatum has been associated with successful memory retrieval but the precise functional link still remains unclear. One hypothesis is that striatal activity reflects an active evaluation process of the retrieval outcome dependent on the current behavioral goals rather than being a consequence of memory reactivation. We have recently shown that the striatum also correlates with confidence in memory recognition, which could reflect high subjective value ascribed to high certainty decisions. To examine whether striatal activity during memory recognition reflects subjective value indeed, we conducted an fMRI study using a recognition memory paradigm in which the participants rated not only the recognition confidence but also indicated the pleasantness associated with the previous memory retrieval. The results demonstrated a high positive correlation between confidence and pleasantness both on the behavioral and brain activation level particularly in the striatum. As almost all of variance in the striatal confidence signal could be explained by experienced pleasantness, this part of the striatal memory recognition response probably corresponds to greater subjective value of high confidence responses. While perceived oldness was also strongly correlated with striatal activity, this activation pattern was clearly distinct from that associated with confidence and pleasantness and thus could not be explained by higher subjective value to detect "old" items. Together, these results show that at least two independent processes contribute to striatal activation in recognition memory: a more flexible evaluation response dependent on context and goals captured by memory confidence and a potentially retrieval-related response captured by perceived oldness. PMID:25868676

  16. Soil Moisture Retrieval from Active/Passive Microwave Observation Synergy Using a Neural Network Approach

    NASA Astrophysics Data System (ADS)

    Kolassa, J.; Gentine, P.; Aires, F.; Prigent, C.

    2014-12-01

    In November 2014 NASA will launch the Soil Moisture Active/Passive (SMAP) mission carrying an L-band radiometer and radar sensor to observe surface soil moisture globally. This new type of instrument requires the development of innovative retrieval algorithms that are able to account for the different surface contributions to the satellite signal and at the same time can optimally exploit the synergy of active and passive microwave data. In this study, a neural network (NN) based retrieval algorithm has been developed using the example of active microwave observations from ASCAT and passive microwave observations from AMSR-E. In a first step, different preprocessing techniques, aiming to highlight the various contributions to the satellite signal, have been investigated. It was found that in particular for the passive microwave observations, the use of multiple frequencies and preprocessing steps could help the retrieval to disentangle the effects of soil moisture, vegetation and surface temperature. A spectral analysis investigated the temporal patterns in the satellite observations and thus assessed which soil moisture temporal variations could realistically be retrieved. The preprocessed data was then used in a NN based retrieval to estimate daily volumetric surface soil moisture at the global scale for the period 2002-2013. It could be shown that the synergy of data from the two sensors yielded a significant improvement of the retrieval performance demonstrating the benefit of multi-sensor approaches as proposed for SMAP. A comparison with a more traditional retrieval product merging approach furthermore showed that the NN technique is better able to exploit the complementarity of information provided by active and passive sensors. The soil moisture retrieval product was evaluated in the spatial, temporal and frequency domain against retrieved soil moisture from WACMOS and SMOS, modeled fields from ERA-interim/Land and in situ observations from the

  17. Active retrieval facilitates across-episode binding by modulating the content of memory

    PubMed Central

    Bridge, Donna J.; Voss, Joel L.

    2014-01-01

    The contents of memory can be updated when information from the current episode is bound with content retrieved from previous episodes. Little is known regarding factors that determine the memory content that is subject to this across-episode binding. We tested whether across-episode binding preferentially occurs for memory content that is currently “active” and identified relevant neural correlates. After studying objects at specific locations on scene backgrounds, subjects performed one of two retrieval tasks for the objects on different scene backgrounds. In an active condition, subjects recalled object locations, whereas subjects merely dragged objects to predetermined locations in a passive condition. Immediately following each object-location retrieval event, a novel face appeared on a blank screen. We hypothesized that the original episode content would be active in memory during face encoding in the active condition, but not in the passive condition (despite seeing the same content in both conditions). A ramification of the active condition would thus be preferential binding of original episode content to novel faces, with no such across-episode binding in the passive condition. Indeed, memory for faces was better when tested on the original background scenes in the active relative to passive condition, indicating that original episode content was bound with the active condition faces, whereas this occurred to a lesser extent for the passive condition faces. Likewise, early-onset negative ERP effects reflected binding of the face to the original episode content in the active but not the passive condition. In contrast, binding in the passive condition occurred only when faces were physically displayed on the original scenes during recognition testing, and a very similar early-onset negative ERP effect signaled binding in this condition. ERP correlates of binding were thus similar for across-episode and within-episode binding (and were distinct from other

  18. Information Retrieval by Constrained Spreading Activation in Semantic Networks.

    ERIC Educational Resources Information Center

    Cohen, Paul R.; Kjeldsen, Rick

    1987-01-01

    Describes GRANT, an expert system for finding sources of funding given research proposals. The architecture of GRANT and the implementation of constrained spreading activation (a modified search algorithm based on semantic memory) are described, and recall and precision rates are analyzed. (Author/LRW)

  19. Retrieval of Precipitation Profiles from Multiresolution, Multifrequency, Active and Passive Microwave Observations

    NASA Technical Reports Server (NTRS)

    Grecu, Mircea; Anagnostou, Emmanouil N.; Olson, William S.; Starr, David OC. (Technical Monitor)

    2002-01-01

    In this study, a technique for estimating vertical profiles of precipitation from multifrequency, multiresolution active and passive microwave observations is investigated using both simulated and airborne data. The technique is applicable to the Tropical Rainfall Measuring Mission (TRMM) satellite multi-frequency active and passive observations. These observations are characterized by various spatial and sampling resolutions. This makes the retrieval problem mathematically more difficult and ill-determined because the quality of information decreases with decreasing resolution. A model that, given reflectivity profiles and a small set of parameters (including the cloud water content, the intercept drop size distribution, and a variable describing the frozen hydrometeor properties), simulates high-resolution brightness temperatures is used. The high-resolution simulated brightness temperatures are convolved at the real sensor resolution. An optimal estimation procedure is used to minimize the differences between simulated and observed brightness temperatures. The retrieval technique is investigated using cloud model synthetic and airborne data from the Fourth Convection And Moisture Experiment. Simulated high-resolution brightness temperatures and reflectivities and airborne observation strong are convolved at the resolution of the TRMM instruments and retrievals are performed and analyzed relative to the reference data used in observations synthesis. An illustration of the possible use of the technique in satellite rainfall estimation is presented through an application to TRMM data. The study suggests improvements in combined active and passive retrievals even when the instruments resolutions are significantly different. Future work needs to better quantify the retrievals performance, especially in connection with satellite applications, and the uncertainty of the models used in retrieval.

  20. Reduced Specificity of Hippocampal and Posterior Ventrolateral Prefrontal Activity during Relational Retrieval in Normal Aging

    ERIC Educational Resources Information Center

    Giovanello, Kelly S.; Schacter, Daniel L.

    2012-01-01

    Neuroimaging studies of episodic memory in young adults demonstrate greater functional neural activity in ventrolateral pFC and hippocampus during retrieval of relational information as compared with item information. We tested the hypothesis that healthy older adults--individuals who exhibit behavioral declines in relational memory--would show…

  1. Prion Protein M129V Polymorphism Affects Retrieval-Related Brain Activity

    ERIC Educational Resources Information Center

    Buchmann, Andreas; Mondadori, Christian R. A.; Hanggi, Jurgen; Aerni, Amanda; Vrticka, Pascal; Luechinger, Roger; Boesiger, Peter; Hock, Christoph; Nitsch, Roger M.; de Quervain, Dominique J.-F.; Papassotiropoulos, Andreas; Henke, Katharina

    2008-01-01

    The prion protein Met129Val polymorphism has recently been related to human long-term memory with carriers of either the 129[superscript MM] or the 129[superscript MV] genotype recalling 17% more words than 129[superscript VV] carriers at 24 h following learning. Here, we sampled genotype differences in retrieval-related brain activity at 30 min…

  2. Reviewing or Retrieving: What Activity Best Promotes Long-Term Retention?

    ERIC Educational Resources Information Center

    Lindgren, Paul D.

    2012-01-01

    Research studies repeatedly emphasize the importance of vocabulary capabilities to a large variety of academic activities. This study compared a learning strategy that exclusively involved the visual review of vocabulary word-definition pairs to a strategy that, in addition, prompted participants to attempt free-recall retrieval of words to match…

  3. Hippocampal inactivation with TTX impairs long-term spatial memory retrieval and modifies brain metabolic activity.

    PubMed

    Conejo, Nélida María; Cimadevilla, José Manuel; González-Pardo, Héctor; Méndez-Couz, Marta; Arias, Jorge Luis

    2013-01-01

    Functional inactivation techniques enable studying the hippocampal involvement in each phase of spatial memory formation in the rat. In this study, we applied tetrodotoxin unilaterally or bilaterally into the dorsal hippocampus to evaluate the role of this brain structure in retrieval of memories acquired 28 days before in the Morris water maze. We combined hippocampal inactivation with the assessment of brain metabolism using cytochrome oxidase histochemistry. Several brain regions were considered, including the hippocampus and other related structures. Results showed that both unilateral and bilateral hippocampal inactivation impaired spatial memory retrieval. Hence, whereas subjects with bilateral hippocampal inactivation showed a circular swim pattern at the side walls of the pool, unilateral inactivation favoured swimming in the quadrants adjacent to the target one. Analysis of cytochrome oxidase activity disclosed regional differences according to the degree of hippocampal functional blockade. In comparison to control group, animals with bilateral inactivation showed increased CO activity in CA1 and CA3 areas of the hippocampus during retrieval, while the activity of the dentate gyrus substantially decreased. However, unilateral inactivated animals showed decreased CO activity in Ammon's horn and the dentate gyrus. This study demonstrated that retrieval recruits differentially the hippocampal subregions and the balance between them is altered with hippocampal functional lesions. PMID:23724089

  4. Hippocampal Inactivation with TTX Impairs Long-Term Spatial Memory Retrieval and Modifies Brain Metabolic Activity

    PubMed Central

    Conejo, Nélida María; Cimadevilla, José Manuel; González-Pardo, Héctor; Méndez-Couz, Marta; Arias, Jorge Luis

    2013-01-01

    Functional inactivation techniques enable studying the hippocampal involvement in each phase of spatial memory formation in the rat. In this study, we applied tetrodotoxin unilaterally or bilaterally into the dorsal hippocampus to evaluate the role of this brain structure in retrieval of memories acquired 28 days before in the Morris water maze. We combined hippocampal inactivation with the assessment of brain metabolism using cytochrome oxidase histochemistry. Several brain regions were considered, including the hippocampus and other related structures. Results showed that both unilateral and bilateral hippocampal inactivation impaired spatial memory retrieval. Hence, whereas subjects with bilateral hippocampal inactivation showed a circular swim pattern at the side walls of the pool, unilateral inactivation favoured swimming in the quadrants adjacent to the target one. Analysis of cytochrome oxidase activity disclosed regional differences according to the degree of hippocampal functional blockade. In comparison to control group, animals with bilateral inactivation showed increased CO activity in CA1 and CA3 areas of the hippocampus during retrieval, while the activity of the dentate gyrus substantially decreased. However, unilateral inactivated animals showed decreased CO activity in Ammon's horn and the dentate gyrus. This study demonstrated that retrieval recruits differentially the hippocampal subregions and the balance between them is altered with hippocampal functional lesions. PMID:23724089

  5. Evaluation of retrieval activities and equipment for removal of containers from the transuranic storage area retrieval enclosure

    SciTech Connect

    Bannister, R.; Rhoden, G.; Davies, G.B.

    1995-09-01

    Since 1970, the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory has accepted over 55,000 cubic meters of Transuranic contaminated hazardous waste for interim storage. The waste has been neatly stored in ``cell`` configurations on adjoining, above ground asphalt pads at the Transuranic Storage Area (TSA). A number of reports have been supplied for review and comment describing the methodology and equipment proposed for retrieval of drums and boxes from a storage facility at the INEL site. The contract for this review requires two main issues to be addressed. First, the adequacy of equipment and methodology for the retrieval of containers which have been breached, lost structural integrity, or are otherwise damaged, Second, to review the strategies and equipment for retrieval of intact waste containers. These issues are presented in the following report along with additional detail in the methodology to complete the description of the operations required for retrieval under most operational scenarios. The documentation reviewed is considered to be at an interim stage and is therefore expected to be subject to the development of the methodology from the existing level of detail with input from the facility operators. This review aims to anticipate some of this development by providing suggested detailed methods of retrieval and equipment for both normal and abnormal operations.

  6. Active and Passive Microwave Retrieval Algorithm for Hydrometeor Concentration Profiles: Application to the HAMP Instrument

    NASA Astrophysics Data System (ADS)

    Orlandi, E.; Mech, M.; Crewell, S.; Lammert, A.

    2012-12-01

    Clouds and precipitation play an important role in the atmospheric water cycle and radiation budget. Unfortunately, the understanding of the processes involved in cloud and precipitation formation and their description in global and regional models are still poor. To improve our understanding of these processes and to reduce model uncertainties, new observation and retrieval techniques are needed. The upcoming Global Precipitation Mission (GPM) provides a combination of a 36 GHz cloud radar and a suite of passive microwave instruments. In the retrieval development process for this and other upcoming missions, airborne platforms are a useful tool to test the algorithms exploiting the synergy of active and passive microwave instruments, and to validate satellite retrievals. In this respect HAMP (Microwave Package for HALO, the High Altitude Long Range aircraft), consisting of a 36 GHz Doppler cloud radar and a 26-channel radiometer, is an ideal test-bed. HAMP radiometers have frequencies along absorption lines (22, 60, 118 and 183 GHz) and in window regions, overlapping with those of AMSU A and B. HAMP will participate in early 2013 in the dedicated remote sensing HALO mission NARVAL (Next-generation Aircraft Remote-sensing for VALidation studies). During NARVAL, the HALO payload will include a water vapor lidar and drop sondes in addition to HAMP. The NARVAL campaign will thus be a excellent opportunity to test a newly developed retrieval algorithm, which exploits the synergy between passive and active microwave observations. In this work we present a Bayesian algorithm to retrieve precipitation rate, liquid and frozen hydrometeor concentration, as well as temperature and humidity profiles from the synergetic use of active and passive microwave nadir observations. Temperature and humidity are derived solely from passive radiometer measurements while the combined cloud radar and radiometer observations are used to retrieve hydrometeor concentration profiles. Lidar

  7. Diagnostic imaging methods applied in long-term surveillance after EVAR. Will computed tomography angiography be replaced by other methods?

    PubMed Central

    Stefaniak, Karolina; Gabriel, Marcin; Oszkinis, Grzegorz

    2016-01-01

    Endovascular implantation of a stent graft in the abdominal aorta (endovascular aneurysm repair – EVAR) is a widely accepted alternative to open surgery in treatment of abdominal aortic aneurysms. Although EVAR is connected with a significant reduction in the risk of peri- and post-operative complications, it does not eliminate them totally. Long-term surveillance of post-EVAR patients is aimed at early detection of and fast reaction to a group of complications called endovascular leaks. Currently, the gold standard in leak diagnostics is computed tomography angiography (CTA). The other methods are ultrasonography, magnetic resonance (MR) angiography, intra-aneurysm sac pressure measurement, X-ray, and digital subtraction angiography (DSA). Despite many analyses based on long-term research, emphasising the high value and competitiveness of less invasive tests such as US or X-ray compared to CTA, it is still difficult for them to win the trust and acceptance of clinicians. The persisting view is that computed tomography is the test that finally resolves any inaccuracies. Consequently, a patient with a number of concurrent diseases is subject to absurdly high radiation exposure and effects of a radiocontrast agent within a short time. It is therefore logical to acknowledge that the EVAR-related risk is catching up with the open surgery risk, while the endovascular procedure is much more costly. Nevertheless, the status of CTA as the gold standard ultimately seems to be unthreatened. This paper presents a description of the diagnostic imaging tests that make it possible to detect any vascular leaks and to develop strategies for therapeutic processes. PMID:26966443

  8. Memory retrieval of inhibitory avoidance requires histamine H1 receptor activation in the hippocampus.

    PubMed

    Fabbri, Roberta; Furini, Cristiane Regina Guerino; Passani, Maria Beatrice; Provensi, Gustavo; Baldi, Elisabetta; Bucherelli, Corrado; Izquierdo, Ivan; de Carvalho Myskiw, Jociane; Blandina, Patrizio

    2016-05-10

    Retrieval represents a dynamic process that may require neuromodulatory signaling. Here, we report that the integrity of the brain histaminergic system is necessary for retrieval of inhibitory avoidance (IA) memory, because rats depleted of histamine through lateral ventricle injections of α-fluoromethylhistidine (a-FMHis), a suicide inhibitor of histidine decarboxylase, displayed impaired IA memory when tested 2 d after training. a-FMHis was administered 24 h after training, when IA memory trace was already formed. Infusion of histamine in hippocampal CA1 of brain histamine-depleted rats (hence, amnesic) 10 min before the retention test restored IA memory but was ineffective when given in the basolateral amygdala (BLA) or the ventral medial prefrontal cortex (vmPFC). Intra-CA1 injections of selective H1 and H2 receptor agonists showed that histamine exerted its effect by activating the H1 receptor. Noteworthy, the H1 receptor antagonist pyrilamine disrupted IA memory retrieval in rats, thus strongly supporting an active involvement of endogenous histamine; 90 min after the retention test, c-Fos-positive neurons were significantly fewer in the CA1s of a-FMHis-treated rats that displayed amnesia compared with in the control group. We also found reduced levels of phosphorylated cAMP-responsive element binding protein (pCREB) in the CA1s of a-FMHis-treated animals compared with in controls. Increases in pCREB levels are associated with retrieval of associated memories. Targeting the histaminergic system may modify the retrieval of emotional memory; hence, histaminergic ligands might reduce dysfunctional aversive memories and improve the efficacy of exposure psychotherapies. PMID:27118833

  9. Aneurysm Sac Pressure Measurement with Minimally Invasive Implantable Pressure Sensors: An Alternative to Current Surveillance Regimes after EVAR?

    SciTech Connect

    Springer, Fabian Guenther, Rolf W.; Schmitz-Rode, Thomas

    2008-05-15

    Current protocols for surveillance after endovascular repair (EVAR) of abdominal aortic aneurysms are mostly based on costly and time-consuming imaging procedures and aim to detect adverse events such as graft migration, endoleaks or aneurysm sac enlargement. These imaging procedures are either associated with radiation exposure to the patients or may be harmful to the patient due to the use of iodine- or gadolinium-containing contrast agents. Furthermore the advantages of EVAR in the short term might be negated by the necessity for endograft surveillance over years. Thus, alternative modalities for follow-up are being investigated. One of these technologies provides pressure information directly from the aneurysm sac. This noninvasive, telemetric pressure sensing was tested in vitro as well as in first clinical trials and was able to identify successful aneurysm exclusion after EVAR. The telemetric pressure sensors showed a promising efficacy and accuracy in detecting type I and type III endoleaks and will help to clarify the clinical relevance of type II endoleaks. This article provides an overview of the in vitro sensors investigated as well as the first clinical trials and the sensors' potential to change the current endograft surveillance regimes.

  10. Cortical Regions Recruited for Complex Active-Learning Strategies and Action Planning Exhibit Rapid Reactivation during Memory Retrieval

    ERIC Educational Resources Information Center

    Voss, Joel L.; Galvan, Ashley; Gonsalves, Brian D.

    2011-01-01

    Memory retrieval can involve activity in the same sensory cortical regions involved in perception of the original event, and this neural "reactivation" has been suggested as an important mechanism of memory retrieval. However, it is still unclear if fragments of experience other than sensory information are retained and later reactivated during…

  11. UP2 400 High Activity Oxide Legacy Waste Retrieval Project Scope and Progress-13048

    SciTech Connect

    Chabeuf, Jean-Michel; Varet, Thierry

    2013-07-01

    The High Activity Oxide facility (HAO) reprocessed sheared and dissolved 4500 metric tons of light water reactor fuel the fuel of the emerging light water reactor spent fuel between 1976 and 1998. Over the period, approximately 2200 tons of process waste, composed primarily of sheared hulls, was produced and stored in a vast silo in the first place, and in canisters stored in pools in subsequent years. Upon shutdown of the facility, AREVA D and D Division in La Hague launched a thorough investigation and characterization of the silos and pools content, which then served as input data for the definition of a legacy waste retrieval and reconditioning program. Basic design was conducted between 2005 and 2007, and was followed by an optimization phase which lead to the definition of a final scenario and budget, 12% under the initial estimates. The scenario planned for the construction of a retrieval and reconditioning cell to be built on top of the storage silo. The retrieved waste would then be rinsed and sorted, so that hulls could subsequently be sent to La Hague high activity compacting facility, while resins and sludge would be cemented within the retrieval cell. Detailed design was conducted successfully from 2008 until 2011, while a thorough research and development program was conducted in order to qualify each stage of the retrieval and reconditioning process, and assist in the elaboration of the final waste package specification. This R and D program was defined and conducted as a response and mitigation of the major project risks identified during the basic design process. Procurement and site preparatory works were then launched in 2011. By the end of 2012, R and D is nearly completed, the retrieval and reconditioning process have been secured, the final waste package specification is being completed, the first equipment for the retrieval cell is being delivered on site, while preparation works are allowing to free up space above and around the silo, to

  12. A New Framework for Robust Retrieval and Fusion of Active/Passive Multi-Sensor Precipitation

    NASA Astrophysics Data System (ADS)

    Ebtehaj, M.; Foufoula-Georgiou, E.; Bras, R. L.

    2014-12-01

    This study introduces a new inversion approach for simultaneous retrieval and optimal fusion of multi-sensor passive/active precipitation spaceborne observations relevant to the Global Precipitation Measurement (GPM) constellation of satellites. This approach uses a modern Maximum a Posteriori (MAP) Bayesian estimator and variational principles to obtain a robust estimate of the rainfall profile from multiple sources of observationally- and physically-based a priori generated databases. The MAP estimator makes use of a constrained mixed and -norm regularization that warranties improved stability and reduced estimation error compared to the classic least-squares estimators, often used in the Bayesian rainfall retrieval techniques. We demonstrate the promise of our framework via detailed algorithmic implementation using the passive and active multi-sensor observations provided by the microwave imager (TMI) and precipitation radar (PR) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite. To this end, we simultaneously obtain an observationally-driven retrieval of the entire precipitation profile using the coincidental TMI-PR observations and then optimally combine it with a first guess derived from physically-consistent a priori collected database of the TMI-2A12 operational product. We elucidate the performance of our algorithm for a wide range of storm environments with a specific focus on extreme and light precipitation events over land and coastal areas for hydrologic applications. The results are also validated versus the ground based observations and the standard TRMM products in seasonal and annual timescales.

  13. Accessibility effects on implicit social cognition: the role of knowledge activation and retrieval experiences.

    PubMed

    Gawronski, Bertram; Bodenhausen, Galen V

    2005-11-01

    Performance on measures of implicit social cognition has been shown to vary as a function of the momentary accessibility of relevant information. The present research investigated the mechanisms underlying accessibility effects of self-generated information on implicit measures. Results from 3 experiments demonstrate that measures based on response compatibility processes (e.g., Implicit Association Test, affective priming with an evaluative decision task) are influenced by subjective feelings pertaining to the ease of retrieving relevant information from memory, whereas measures based on stimulus compatibility processes (e.g., semantic priming with a lexical-decision task) are influenced by direct knowledge activation in associative memory. These results indicate that the mediating mechanisms underlying context effects on implicit measures can differ as a function of the task even when these tasks show similar effects on a superficial level. Implications for research on implicit social cognition and the ease-of-retrieval effect are discussed. PMID:16351361

  14. Retrievals of Falling Snow from Satellite-borne Active and Passive Sensors

    NASA Astrophysics Data System (ADS)

    Jackson, Gail; Munchak, S. Joseph; Johnson, Benjamin

    2014-05-01

    Precipitation, including rain and snow, is a critical part of the Earth's energy and hydrology cycles. Precipitation impacts latent heating profiles locally while global circulation patterns distribute precipitation and energy from the equator to the poles. For the hydrological cycle, falling snow is a primary contributor in northern latitudes during the winter seasons. Falling snow is the source of snow pack accumulations that provide fresh water resources for many communities in the world. Furthermore, falling snow impacts society by causing transportation disruptions during severe snow events. In order to collect information on the complete global precipitation cycle, both liquid and frozen precipitation must be collected. The Global Precipitation Measurement (GPM) mission's Core satellite, scheduled for launch in February 2014, is well designed to detect and estimate falling snow. The GPM core carries a passive radiometer with frequencies (10-183 GHz) and an active radar with Ku- and Ka-band frequencies. Combined with the 65o inclination of the GPM Core satellite, these instruments allow for the GPM Core to sense and retrieve information about falling snow and light rain in regions of the earth where snow is common. The GPM Core's comprehensive active and passive channel set will also allow it to serve as a unifying reference for GPM constellation radiometer satellites. Since falling snow from space is the next precipitation measurement challenge from space, information is needed to guide retrieval algorithm development for these current and future missions. This information includes thresholds of detection for various sensor channel configurations, sensitivity to macroscale snow event system characteristics, and sensitivity to microscale snowflake particle characteristics. While the work in this area will continue for many years to come, our group has made substantial progress in this area by identifying minimum detectable melted rates of ~0.5 mm hr-1. Results

  15. Memory retrieval by activating engram cells in mouse models of early Alzheimer's disease.

    PubMed

    Roy, Dheeraj S; Arons, Autumn; Mitchell, Teryn I; Pignatelli, Michele; Ryan, Tomás J; Tonegawa, Susumu

    2016-03-24

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory decline and subsequent loss of broader cognitive functions. Memory decline in the early stages of AD is mostly limited to episodic memory, for which the hippocampus has a crucial role. However, it has been uncertain whether the observed amnesia in the early stages of AD is due to disrupted encoding and consolidation of episodic information, or an impairment in the retrieval of stored memory information. Here we show that in transgenic mouse models of early AD, direct optogenetic activation of hippocampal memory engram cells results in memory retrieval despite the fact that these mice are amnesic in long-term memory tests when natural recall cues are used, revealing a retrieval, rather than a storage impairment. Before amyloid plaque deposition, the amnesia in these mice is age-dependent, which correlates with a progressive reduction in spine density of hippocampal dentate gyrus engram cells. We show that optogenetic induction of long-term potentiation at perforant path synapses of dentate gyrus engram cells restores both spine density and long-term memory. We also demonstrate that an ablation of dentate gyrus engram cells containing restored spine density prevents the rescue of long-term memory. Thus, selective rescue of spine density in engram cells may lead to an effective strategy for treating memory loss in the early stages of AD. PMID:26982728

  16. Aquarius geophysical model function and combined active passive algorithm for ocean surface salinity and wind retrieval

    NASA Astrophysics Data System (ADS)

    Yueh, Simon; Tang, Wenqing; Fore, Alexander; Hayashi, Akiko; Song, Yuhe T.; Lagerloef, Gary

    2014-08-01

    This paper describes the updated Combined Active-Passive (CAP) retrieval algorithm for simultaneous retrieval of surface salinity and wind from Aquarius' brightness temperature and radar backscatter. Unlike the algorithm developed by Remote Sensing Systems (RSS), implemented in the Aquarius Data Processing System (ADPS) to produce Aquarius standard products, the Jet Propulsion Laboratory's CAP algorithm does not require monthly climatology SSS maps for the salinity retrieval. Furthermore, the ADPS-RSS algorithm fully uses the National Center for Environmental Predictions (NCEP) wind for data correction, while the CAP algorithm uses the NCEP wind only as a constraint. The major updates to the CAP algorithm include the galactic reflection correction, Faraday rotation, Antenna Pattern Correction, and geophysical model functions of wind or wave impacts. Recognizing the limitation of geometric optics scattering, we improve the modeling of the reflection of galactic radiation; the results are better salinity accuracy and significantly reduced ascending-descending bias. We assess the accuracy of CAP's salinity by comparison with ARGO monthly gridded salinity products provided by the Asia-Pacific Data-Research Center (APDRC) and Japan Agency for Marine-Earth Science and Technology (JAMSTEC). The RMS differences between Aquarius CAP and APDRC's or JAMSTEC's ARGO salinities are less than 0.2 psu for most parts of the ocean, except for the regions in the Intertropical Convergence Zone, near the outflow of major rivers and at high latitudes.

  17. Extinction and Retrieval + Extinction of Conditioned Fear Differentially Activate Medial Prefrontal Cortex and Amygdala in Rats.

    PubMed

    Lee, Hongjoo J; Haberman, Rebecca P; Roquet, Rheall F; Monfils, Marie-H

    2015-01-01

    Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a footshock) leads to associative learning such that the tone alone comes to elicit a conditioned response (e.g., freezing). We have previously shown that an extinction session that occurs within the reconsolidation window (termed retrieval + extinction) attenuates fear responding and prevents the return of fear in Pavlovian fear conditioning (Monfils et al., 2009). To date, the mechanisms that explain the different behavioral outcomes between standard extinction and retrieval + extinction remain poorly understood. Here we sought to examine the differential temporal engagement of specific neural systems by these two approaches using Arc catFISH (cellular compartment analysis of temporal activity using fluorescence in situ hybridization (FISH)). Our results demonstrate that extinction and retrieval + extinction lead to differential patterns of expression, suggesting that they engage different networks. These findings provide insight into the neural mechanisms that allow extinction during reconsolidation to prevent the return of fear in rodents. PMID:26834596

  18. Extinction and Retrieval + Extinction of Conditioned Fear Differentially Activate Medial Prefrontal Cortex and Amygdala in Rats

    PubMed Central

    Lee, Hongjoo J.; Haberman, Rebecca P.; Roquet, Rheall F.; Monfils, Marie-H.

    2016-01-01

    Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a footshock) leads to associative learning such that the tone alone comes to elicit a conditioned response (e.g., freezing). We have previously shown that an extinction session that occurs within the reconsolidation window (termed retrieval + extinction) attenuates fear responding and prevents the return of fear in Pavlovian fear conditioning (Monfils et al., 2009). To date, the mechanisms that explain the different behavioral outcomes between standard extinction and retrieval + extinction remain poorly understood. Here we sought to examine the differential temporal engagement of specific neural systems by these two approaches using Arc catFISH (cellular compartment analysis of temporal activity using fluorescence in situ hybridization (FISH)). Our results demonstrate that extinction and retrieval + extinction lead to differential patterns of expression, suggesting that they engage different networks. These findings provide insight into the neural mechanisms that allow extinction during reconsolidation to prevent the return of fear in rodents. PMID:26834596

  19. Current technology for the treatment of infection following abdominal aortic aneurysm (AAA) fixation by endovascular repair (EVAR).

    PubMed

    Capoccia, L; Mestres, G; Riambau, V

    2014-06-01

    In recent years, in parallel with the increase of endovascular aortic repair (EVAR) procedures performances, a rise of late open surgical removal of EVAR implants has been observed, due to non-endovascularly correctable graft complications. Among them endograft infection is a rare but devastating occurrence, accounting for an incidence ranging from 0.2% to 0.7% in major series, and almost 1% of all causes of endograft explantations. However, a real estimation of the incidence of the problem respect to the number of EVAR implantations is difficult to obtain. Time to infection is usually defined as the period between EVAR and presentation of symptoms that leads to the infection diagnosis. It can be extremely variable, depending on bacterial virulence and host conditions. The diagnosis of an endograft infection is usually based on a combination of clinical symptoms, imaging studies and microbial cultures whenever possible. If computed tomography (CT) scan is employed in almost 100% of infection diagnosis, a combination of fluorodeoxyglucose-positron emission tomography (FDG-PET) and CT scan is nowadays used with increasing frequency in order to rise the likelihood of detecting a graft infection, since even cultures of blood or samples collected from the infected field can sometimes be negative. Complete graft excision seems the best approach whenever a surgical reconstruction could be attempted. In situ reconstruction can be performed by the interposition of an autologous vein, a cryopreserved allograft or a rifampin-soaked Dacron graft. The so-called conventional treatment contemplates the re-establishment of vascularization through extranatomical routes, thus preserving the new graft material from possible contamination by the surgical field just cleaned. When severe comorbid conditions did not allow graft excision, a conservative treatment should be taken into account. It is mainly based on broad-spectrum or culture-specific antibiotic therapy combined, whenever

  20. Retrievals of Falling Snow from Satellite-borne Active and Passive Sensors

    NASA Astrophysics Data System (ADS)

    Skofronick-Jackson, Gail; Munchak, S. Joseph; Johnson, Benjamin

    2013-04-01

    Precipitation, including rain and snow, is a critical part of the Earth's energy and hydrology cycles. Precipitation impacts latent heating profiles locally while global circulation patterns distribute precipitation and energy from the equator to the poles. For the hydrological cycle, falling snow is a primary contributor in northern latitudes during the winter seasons. Falling snow is the source of snow pack accumulations that provide fresh water resources for many communities in the world. Furthermore, falling snow impacts society by causing transportation disruptions during severe snow events. In order to collect information on the complete global precipitation cycle, both liquid and frozen precipitation must be collected. The Global Precipitation Measurement (GPM) mission's Core satellite, scheduled for launch in 2014, is well designed to detect and estimate falling snow. The GPM core carries a passive radiometer with frequencies (10-183 GHz) and an active radar with Ku- and Ka-band frequencies. Combined with the 65 degree inclination of the GPM Core satellite, these instruments allow for the GPM Core to sense and retrieve information about falling snow and light rain in regions of the earth where snow is common. The GPM Core's comprehensive active and passive channel set will also allow it to serve as a unifying reference for GPM constellation radiometer satellites. Since falling snow from space is the next precipitation measurement challenge from space, information is needed to guide retrieval algorithm development for these current and future missions. This information includes thresholds of detection for various sensor channel configurations, sensitivity to macroscale snow event system characteristics, and sensitivity to microscale snowflake particle characteristics. While the work in this area will continue for many years to come, our group has made substantial progress in this area by identifying minimum detectable melted rates of ~0.5 mm/hr. Results will

  1. Functional brain activation during retrieval of visceral pain-conditioned passive avoidance in the rat.

    PubMed

    Wang, Zhuo; Bradesi, Sylvie; Charles, Jonathan R; Pang, Raina D; Maarek, Jean-Michel I; Mayer, Emeran A; Holschneider, Daniel P

    2011-12-01

    This study assessed functional brain activation in rats during expectation of visceral pain. Male rats were trained in step-down passive avoidance (PA) for 2 days. Upon stepping down from a platform, conditioned animals received noxious colorectal distension delivered through a colorectal balloon, whereas the balloon in control rats remained uninflated. On day 3, PA behavior was assessed while [(14)C]-iodoantipyrine was infused intravenously, followed by immediate euthanasia. Regional cerebral blood flow-related tissue radioactivity (rCBF) was analyzed by statistical parametric mapping using 3-dimensional brains reconstructed from autoradiographic brain slice images. Associated with retrieved PA behavior, conditioned rats compared with control subjects showed increases in rCBF in sensory (anterior insula, somatosensory cortex), limbic/paralimbic regions (anterior cingulate, prelimbic cortex, amygdala), all regions previously reported to show activation during acute visceral pain. Increases in rCBF were also noted in the dorsal hippocampus, nucleus accumbens, and caudate putamen, regions associated with retrieval of PA. Organization of the underlying brain network was further delineated by functional connectivity analysis. This revealed in conditioned rats a strongly and positively connected corticostriatal cluster (cingulate, prelimbic cortex, caudate putamen). The amygdala and cerebellar hemispheres formed another positively connected cluster, which was negatively connected with the corticostriatal cluster, suggesting corticolimbic modulation. Prelimbic cortex, nucleus accumbens, and anterior insula emerged in conditioned animals as hubs. Our results show that during retrieval of PA, brain areas implicated in PA expression as well as those implicated in acute visceral pain processing were recruited, in line with findings from human brain imaging studies on pain expectation. PMID:21944154

  2. Retrieval of Precipitation Profiles from Multiresolution, Multifrequency Active and Passive Microwave Observations.

    NASA Astrophysics Data System (ADS)

    Grecu, Mircea; Olson, William S.; Anagnostou, Emmanouil N.

    2004-04-01

    In this study, a technique for estimating vertical profiles of precipitation from multifrequency, multiresolution active and passive microwave observations is investigated. The technique is applicable to the Tropical Rainfall Measuring Mission (TRMM) observations, and it is based on models that simulate high-resolution brightness temperatures as functions of observed reflectivity profiles and a parameter related to the raindrop size distribution. The modeled high-resolution brightness temperatures are used to determine normalized brightness temperature polarizations at the microwave radiometer resolution. An optimal estimation procedure is employed to minimize the differences between the simulated and observed normalized polarizations by adjusting the drop size distribution parameter. The impact of other unknowns that are not independent variables in the optimal estimation, but affect the retrievals, is minimized through statistical parameterizations derived from cloud model simulations. The retrieval technique is investigated using TRMM observations collected during the Kwajalein Experiment (KWAJEX). These observations cover an area extending from 5° to 12°N latitude and from 166° to 172°E longitude from July to September 1999 and are coincident with various ground-based observations, facilitating a detailed analysis of the retrieved precipitation. Using the method developed in this study, precipitation estimates consistent with both the passive and active TRMM observations are obtained. Various parameters characterizing these estimates, that is, the rain rate, precipitation water content, drop size distribution intercept, and the mass- weighted mean drop diameter, are in good qualitative agreement with independent experimental and theoretical estimates. Combined rain estimates are, in general, higher than the official TRMM precipitation radar (PR)-only estimates for the area and the period considered in the study. Ground-based precipitation estimates, derived

  3. The role of phonological activation in the visual semantic retrieval of Chinese characters.

    PubMed

    Guo, Taomei; Peng, Danling; Liu, Ying

    2005-12-01

    The Stroop paradigm was used to examine the role of phonological activation in semantic access and its development in reading Chinese characters. Subjects (age 7-23 years) of different reading ability were asked to name the display color of Chinese characters. The characters were displayed in four different colors: red, yellow, blue and green. There were five types of relationships between a character and its display color: semantically congruent, phonologically congruent, semantically incongruent, phonologically incongruent and neutral. In addition to the classical Stroop effects, interference and facilitation effects from the homophones of color characters were also observed. The younger children and those with lower reading ability exhibited stronger Stroop effects. These findings suggest that phonological codes are activated automatically in Chinese character recognition. Furthermore, there is more phonological activation in the semantic retrieval of children in lower grades and those with lower reading ability. PMID:15992794

  4. The Influence of Prior Knowledge on the Retrieval-Directed Function of Note Taking in Prior Knowledge Activation

    ERIC Educational Resources Information Center

    Wetzels, Sandra A. J.; Kester, Liesbeth; van Merrienboer, Jeroen J. G.; Broers, Nick J.

    2011-01-01

    Background: Prior knowledge activation facilitates learning. Note taking during prior knowledge activation (i.e., note taking directed at retrieving information from memory) might facilitate the activation process by enabling learners to build an external representation of their prior knowledge. However, taking notes might be less effective in…

  5. Increased Neural Activation during Picture Encoding and Retrieval in 60-Year-Olds Compared to 20-Year-Olds

    ERIC Educational Resources Information Center

    Burgmans, S.; van Boxtel, M. P. J.; Vuurman, E. F. P. M.; Evers, E. A. T.; Jolles, J.

    2010-01-01

    Brain aging has been associated with both reduced and increased neural activity during task execution. The purpose of the present study was to investigate whether increased neural activation during memory encoding and retrieval is already present at the age of 60 as well as to obtain more insight into the mechanism behind increased activity.…

  6. Differential involvement of glutamatergic and catecholaminergic activity within the amygdala during taste aversion retrieval on memory expression and updating.

    PubMed

    Daniel, Osorio-Gómez; Kioko, Guzmán-Ramos; Federico, Bermúdez-Rattoni

    2016-07-01

    During memory retrieval, consolidated memories are expressed and destabilized in order to maintain or update information through a memory reconsolidation process. Despite the key role of the amygdala during memory acquistion and consolidation, the participation of neurotransmitter signals in memory retrieval is poorly understood. Hence, we used conditioned taste aversion and in vivo microdialysis to evaluate changes in glutamate, norepinephrine and dopamine concentrations within the amygdala during memory retrieval. We observed that exposure to an aversive-conditioned stimulus induced an augmentation in glutamate, norepinephrine and dopamine levels within the amygdala, while exposure to a familiar and safe stimulus did not induce changes in these neurotransmitters levels. Also, we evaluated the amygdalar blockade of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), N-methyl-d-aspartate (NMDA), β-adrenergic and dopamine D1 receptors in memory retrieval and updating. Results showed that during retrieval, behavioural expression was impaired by intra-amygdalar blockade of AMPA and β-adrenergic receptors, whereas NMDA, D1 and β-adrenergic receptors blockade hindered memory updating. In summary, during conditioned taste aversion retrieval there was an increase in the extracellular levels of glutamate, norepinephrine and dopamine within the amygdala, and their receptors activity were differentially involved in the behavioural expression and memory updating during retrieval. PMID:27018173

  7. Aquarius Wind and SSS Retrieved Using the Combined Active-Passive Algorithm under All Weather Conditions

    NASA Astrophysics Data System (ADS)

    Yueh, S. H.; Tang, W.; Fore, A.; Freedman, A. P.; Neumann, G.; Hayashi, A.; Lagerloef, G. S.

    2012-12-01

    The Aquarius/SACD satellite was launched on June 10, 2011, and the Aquarius instrument has been operational since August 25, 2012. Aquarius is a combined passive/active L-band microwave instrument developed to map the salinity field at the surface of the ocean from space. The primary science objective of the Aquarius mission is to monitor the seasonal and interannual variation of the large scale features of the sea surface salinity (SSS) field in the open ocean with a spatial resolution of 150 km and a retrieval accuracy of 0.2 psu globally on a monthly basis. The measurement principle is based on the response of the L-band (1.413 GHz) sea surface brightness temperatures to sea surface salinity. To achieve the required 0.2 psu accuracy, the impact of sea surface roughness (e.g. wind-generated ripples and waves), along with several additional factors impacting the observed brightness temperature, must be corrected to better than a few tenths of a degree Kelvin. To this end, Aquarius includes a scatterometer to help correct for this surface roughness effect. In this paper we describe the characteristics and error estimates of the ocean surface wind vector and SSS retrieved using the Combined Active-Passive (CAP) algorithm, which does not use the NCEP wind for correcting Aquarius' brightness temperatures. Error estimates using the triple collocation analyses of SSM/I, NCEP and Aquarius-CAP winds indicate that the retrieved Aquarius wind speed accuracy is excellent with a random error of about 0.75 m s-1 for rain-free conditions. For rainy conditions when there were no SSM/I wind retrievals, we used the WindSAT-AW or ASCAT winds together with NCEP and CAP winds for triple collocation analysis. It is shown that Aquarius CAP wind speed is the most accurate under rainy conditions with RMS error below 2 m/s at 10 mm/h rain rate. In comparison with the NCEP wind direction, the Aquarius wind direction retrievals also appear accurate for above 10 m s-1. We further examine the

  8. Retrieval of Sea Surface Salinity and Wind from The NASA Soil Moisture Active Passive Mission Data

    NASA Astrophysics Data System (ADS)

    Yueh, S. H.; Fore, A.; Tang, W.; Hayashi, A.

    2015-12-01

    NASA's Soil Moisture Active Passive (SMAP) mission, the first Earth Science Decadal Survey mission, was launched January 31, 2015 to provide high-resolution, frequent-revisit global mapping of soil moisture. SMAP has two instruments, a polarimetric radiometer and a multi-polarization synthetic aperture radar. Both instruments operate at L-band frequencies (~ 1GHz) and share a single 6-m rotating mesh antenna, producing a fixed incidence angle conical scan at 40⁰ across a 1000-km swath and a 2-3 day global revisit. The SMAP SSS and ocean surface wind retrieval algorithm developed at the Jet Propulsion Laboratory leverages the QuikSCAT and Aquarius algorithms to account for the two-look geometry (fore and aft looks from the conical scan) and dual-polarization observations for simultaneous retrieval of SSS and wind speed. The retrieval algorithm has been applied to more than three months of SMAP radiometer data. Comparison with the European Center for Medium-Range Weather Forecasting (ECMWF) wind speed suggests that the SMAP wind speed reaches an accuracy of about 0.7 ms-1. The preliminary assessment of the SMAP SSS products gridded at 50 km spatial resolution and weekly intervals is promising. The spatial patterns of the SSS agree well with climatological distributions, but exhibit several unique spatial and temporal features. The temporal evolutions of freshwater plumes from several major rivers, such as the Amazon, Niger, Congo, Ganges, and Mississippi, are all consistent with the timing of rainy and dry seasons, indicated in the SMAP's soil moisture products. Rigorous accuracy assessment will be performed by comparison with in situ SSS data from buoys and ARGO floats. The SMAP evaluation products will be released to the public prior to November 2015.

  9. Standard and fenestrated endograft sizing in EVAR planning: Description and validation of a semi-automated 3D software.

    PubMed

    Macía, Iván; de Blas, Mariano; Legarreta, Jon Haitz; Kabongo, Luis; Hernández, Óscar; Egaña, José María; Emparanza, José Ignacio; García-Familiar, Ainhoa; Graña, Manuel

    2016-06-01

    An abdominal aortic aneurysm (AAA) is a pathological dilation of the abdominal aorta that may lead to a rupture with fatal consequences. Endovascular aneurysm repair (EVAR) is a minimally invasive surgical procedure consisting of the deployment and fixation of a stent-graft that isolates the damaged vessel wall from blood circulation. The technique requires adequate endovascular device sizing, which may be performed by vascular analysis and quantification on Computerized Tomography Angiography (CTA) scans. This paper presents a novel 3D CTA image-based software for AAA inspection and EVAR sizing, eVida Vascular, which allows fast and accurate 3D endograft sizing for standard and fenestrated endografts. We provide a description of the system and its innovations, including the underlying vascular image analysis and visualization technology, functional modules and user interaction. Furthermore, an experimental validation of the tool is described, assessing the degree of agreement with a commercial, clinically validated software, when comparing measurements obtained for standard endograft sizing in a group of 14 patients. PMID:25747803

  10. The retrieval of self-defining memories is associated with the activation of specific working selves.

    PubMed

    Çili, Soljana; Stopa, Lusia

    2015-01-01

    This article presents two studies that investigated the impact of the retrieval of self-defining memories on individuals' sense of self. Participants recalled positive and/or negative self-defining memories, rated memory characteristics and completed measures focusing on different self-aspects. Study 1 found that participants reported higher state self-esteem after recalling a positive memory than after recalling a negative one. They also reported lower negative self-consistency and higher state self-concept clarity and positive self-consistency, but this result became non-significant after controlling for state self-esteem. Study 2 found that participants reported higher state self-esteem, a marginally higher proportion of recreation/exploration, goals and a marginally lower proportion of achievement goals after recalling a positive memory than after recalling a negative one. They also reported a higher proportion of self-cognitions referring to emotional states after recalling memories from which they had not abstracted meaning than after recalling memories from which they had done this. These findings suggest that the retrieval of vivid, emotional and highly self-relevant memories may be accompanied by the activation of specific self-representations or working selves. They also suggest that the experience of memory-related intrusive images may temporarily influence individuals' sense of self. The implications of these findings for clinical practice are discussed. PMID:24528183

  11. Multi-Standard Metadata Retrieval Framework at the Physical Oceanography Distributed Active Archive Center

    NASA Astrophysics Data System (ADS)

    Chung, N. T.; Huang, T.; Armstrong, E. M.; Gangl, M. E.

    2012-12-01

    With the vast amount of Earth Science data available, providing the user community with high quality metadata to facilitate information retrieval and exchange is integral to scientific research. The Physical Oceanography Distributed Active Archive Center (PO.DAAC) archives and distributes data products along with metadata pertinent to the physical state of the ocean. As one of the Earth Science data center for NASA, PO.DAAC is expected to work with multiple metadata standards. Since there is no single metadata standard that meets everyone's needs, a web-based framework has been designed and integrated as part of PO.DAAC's scalable Core Data System to enable users to quickly retrieve metadata in the format that they need. Currently, the framework supports the Open Search specification for data discovery, ISO 19115-2, Global Change Master Directory (GCMD) and Federal Geographic Data Committee (FGDC) metadata standards, with new metadata standards still being added. In this talk we will present the architecture behind the framework that makes it possible to support various metadata standards as well as the challenges we encountered.

  12. Relatedness-dependent rapid development of brain activity in anterior temporal cortex during pair-association retrieval.

    PubMed

    Jimura, Koji; Hirose, Satoshi; Wada, Hiroyuki; Yoshizawa, Yasunori; Imai, Yoshio; Akahane, Masaaki; Machida, Toru; Shirouzu, Ichiro; Koike, Yasuharu; Konishi, Seiki

    2016-08-01

    Functional MRI studies have revealed that the brain activity in the anterior temporal cortex during memory retrieval increases over months after memory encoding. Behavioral evidence has demonstrated that long-term memory can sometimes be consolidated more rapidly in one or two days. In the present functional MRI study, we manipulated the relatedness between paired faces to be retrieved in a pair-association task. The brain activity in the anterior temporal cortex during retrieval of paired associates increased rapidly in one day, as shown in previous studies. We found that the speed of the brain activity development was dependent on the level of semantic relatedness of paired faces. The results suggest that the semantic relatedness enhances the speed of formation of memory representation in the anterior temporal cortex. PMID:27233220

  13. Landscape freeze/thaw retrievals from soil moisture active passive (SMAP) L-band radar measurements

    NASA Astrophysics Data System (ADS)

    Colliander, A.; Derksen, C.

    2015-12-01

    The NASA Soil Moisture Active Passive (SMAP) mission produces a daily landscape freeze/thaw product (L3_FT_A) which provides categorical (frozen, thawed, or [inverse] transitional) classification of the surface state (for land areas north of 45°N) derived from ascending and descending orbits of SMAP high-resolution L-band radar measurements. The FT retrievals are output to 3 km resolution polar and global grids with temporal revisit of 2 days or better north of ~55°N and 3 days or better north of 45°N. The algorithm classifies the land surface freeze/thaw state based on the time series of L-band radar backscatter compared to frozen and thawed reference states. This presentation will describe pre-launch L3_FT_A algorithm implementation and evaluation using NASA/SAC-D Aquarius L-band radar data, and provide an update on the current status of the SMAP L3_FT_A product. In advance of SMAP measurements, the L3_FT_A algorithm was configured and evaluated using Aquarius measurements. While the temporal (weekly) and spatial (~100 km) resolution is much coarser than SMAP, Aquarius provides L-band radar measurements at an incidence angle (normalized to 40 degrees) which is close to SMAP. Evaluation of FT retrievals derived using both Aquarius freeze/thaw references and backscatter time series as inputs identified good agreement during the fall freeze-up period with FT flag agreement (Aquarius versus in situ) exceeding the 80% SMAP mission requirement when summarized on a monthly basis. Disagreement was greater during the spring thaw transition due in part to uncertainty in characterizing the surface state from in situ measurements and backscatter sensitivity to the onset of snow melt, independent of the soil temperature beneath the snowpack. Initial challenges for SMAP derived FT retrievals include the scale difference between the Aquarius references (~100 km) and the SMAP measurements (3 km) which is particularly problematic in areas of complex topography and/or mixed

  14. Connectionist Interaction Information Retrieval.

    ERIC Educational Resources Information Center

    Dominich, Sandor

    2003-01-01

    Discussion of connectionist views for adaptive clustering in information retrieval focuses on a connectionist clustering technique and activation spreading-based information retrieval model using the interaction information retrieval method. Presents theoretical as well as simulation results as regards computational complexity and includes…

  15. Brain activation during associative short-term memory maintenance is not predictive for subsequent retrieval

    PubMed Central

    Bergmann, Heiko C.; Daselaar, Sander M.; Beul, Sarah F.; Rijpkema, Mark; Fernández, Guillén; Kessels, Roy P. C.

    2015-01-01

    Performance on working memory (WM) tasks may partially be supported by long-term memory (LTM) processing. Hence, brain activation recently being implicated in WM may actually have been driven by (incidental) LTM formation. We examined which brain regions actually support successful WM processing, rather than being confounded by LTM processes, during the maintenance and probe phase of a WM task. We administered a four-pair (faces and houses) associative delayed-match-to-sample (WM) task using event-related functional MRI (fMRI) and a subsequent associative recognition LTM task, using the same stimuli. This enabled us to analyze subsequent memory effects for both the WM and the LTM test by contrasting correctly recognized pairs with incorrect pairs for either task. Critically, with respect to the subsequent WM effect, we computed this analysis exclusively for trials that were forgotten in the subsequent LTM recognition task. Hence, brain activity associated with successful WM processing was less likely to be confounded by incidental LTM formation. The subsequent LTM effect, in contrast, was analyzed exclusively for pairs that previously had been correctly recognized in the WM task, disclosing brain regions involved in successful LTM formation after successful WM processing. Results for the subsequent WM effect showed no significantly activated brain areas for WM maintenance, possibly due to an insensitivity of fMRI to mechanisms underlying active WM maintenance. In contrast, a correct decision at WM probe was linked to activation in the “retrieval success network” (anterior and posterior midline brain structures). The subsequent LTM analyses revealed greater activation in left dorsolateral prefrontal cortex and posterior parietal cortex in the early phase of the maintenance stage. No supra-threshold activation was found during the WM probe. Together, we obtained clearer insights in which brain regions support successful WM and LTM without the potential confound

  16. Brain activity during source memory retrieval in young, middle-aged and old adults.

    PubMed

    Cansino, Selene; Trejo-Morales, Patricia; Estrada-Manilla, Cinthya; Pasaye-Alcaraz, Erick Humberto; Aguilar-Castañeda, Erika; Salgado-Lujambio, Perla; Sosa-Ortiz, Ana Luisa

    2015-08-27

    We investigated neurofunctional changes associated with source memory decline across the adult life span using functional magnetic resonance imaging (fMRI). Young, middle-aged and old adults carried out a natural/artificial judgment of images of common objects that were randomly presented in one of the quadrants of the screen. At retrieval, the images were displayed at the center of the screen and the participants judged whether each image was new or old and, if old, they indicated in which quadrant of the screen the image had originally been presented. Comparing the items associated with correct versus incorrect source judgments revealed that no regions showed greater activity in young adults than in middle-aged adults; however, in young and middle-aged adults the activity in the left hippocampus and left anterior temporal cortex was of greater magnitude than in the older adults. Several regions also exhibited greater activity in young adults than in old adults. These results suggest that in middle age the recollection neural network, assessable by fMRI, is still preserved. PMID:26054305

  17. Basolateral amygdala activity during the retrieval of associative learning under anesthesia.

    PubMed

    Fenton, G E; Spicer, C H; Halliday, D M; Mason, R; Stevenson, C W

    2013-03-13

    Associative learning can occur under anesthesia and its neural correlates have begun to be elucidated. During discrimination learning under anesthesia in rats, lateral amygdala excitability increases in response to a conditioned stimulus (CS+) previously paired with electrical stimulation of the paw but not to another stimulus presented alone (CS-). Similarly, medial prefrontal cortex activity increases selectively during CS+ presentation after discrimination learning but this occurs only in neurons receiving input from the basolateral amygdala (BLA), the main source of amygdaloid projections to this region. However, BLA activity during discrimination learning under anesthesia has not been investigated. Here we used in vivo electrophysiology to examine BLA activity before and after associative learning and during later memory retrieval in anesthetized rats. We examined extracellular unit and local field potential (LFP) activity using an auditory discrimination learning paradigm. Rats were repeatedly presented with two distinct sounds, one of which was paired with electrical stimulation of the paw. One hour later, the paired sound (CS+) was presented alone along with the sound not paired with electrical stimulation (CS-). We found increased unit firing late (1 h) but not early (5 min) after learning. LFP power was increased both early and late after learning. In control experiments we also found increased unit and LFP activity late after electrical stimulation alone. After discrimination learning, unit firing increased in response to CS+, but not CS-, presentation. LFP power also showed a modest increase during CS+, compared to CS-, presentation. These findings suggest that discrimination learning under anesthesia can occur at the neural level in BLA. The potential relevance of these results is discussed in relation to previous studies examining neural activity during fear learning and memory processing in conscious animals. PMID:23295986

  18. Application of active spaceborne remote sensing for understanding biases between passive cloud water path retrievals

    NASA Astrophysics Data System (ADS)

    Lebsock, Matthew; Su, Hui

    2014-07-01

    Bias between the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) version 2 and the Moderate Resolution Imaging Spectroradiometer (MODIS) collection 5.1 cloud liquid water path (Wc) products are explored with the aid of coincident active observations from the CloudSat radar and the CALIPSO lidar. In terms of detection, the active observations provide precise separation of cloudy from clear sky and precipitating from nonprecipitating clouds. In addition, they offer a unique quantification of precipitation water path (Wp) in warm clouds. They also provide an independent quantification of Wc that is based on an accurate surface reference technique, which is an independent arbiter between the two passive approaches. The results herein establish the potential for CloudSat and CALIPSO to provide an independent assessment of bias between the conventional passive remote sensing methods from reflected solar and emitted microwave radiation. After applying a common data filter to the observations to account for sampling biases, AMSR-E is biased high relative to MODIS in the global mean by 26.4 gm-2. The RMS difference in the regional patterns is 32.4 gm-2, which highlights a large geographical dependence in the bias which is related to the tropical transitions from stratocumulus to cumulus cloud regimes. The contributions of four potential sources for this bias are investigated by exploiting the active observations: (1) bias in MODIS related to solar zenith angle dependence accounts for -2.3 gm-2, (2) bias in MODIS due to undersampling of cloud edges accounts for 4.2 gm-2, (3) a wind speed and water vapor-dependent "clear-sky biase" in the AMSR-E retrieval accounts for 6.3 gm-2, and (4) evidence suggests that much of the remaining 18 gm-2 bias is related to the assumed partitioning of the observed emission signal between cloud and precipitation water in the AMSR-E retrieval. This is most evident through the correlations between the regional mean patterns of Wp and the Wc

  19. Cortical Activation Patterns during Long-Term Memory Retrieval of Visually or Haptically Encoded Objects and Locations

    ERIC Educational Resources Information Center

    Stock, Oliver; Roder, Brigitte; Burke, Michael; Bien, Siegfried; Rosler, Frank

    2009-01-01

    The present study used functional magnetic resonance imaging to delineate cortical networks that are activated when objects or spatial locations encoded either visually (visual encoding group, n = 10) or haptically (haptic encoding group, n = 10) had to be retrieved from long-term memory. Participants learned associations between auditorily…

  20. Contralateral Cortical Organisation of Information in Visual Short-Term Memory: Evidence from Lateralized Brain Activity during Retrieval

    ERIC Educational Resources Information Center

    Fortier-Gauthier, Ulysse; Moffat, Nicolas; Dell'Acqua, Robert; McDonald, John J.; Jolicoeur, Pierre

    2012-01-01

    We studied brain activity during retention and retrieval phases of two visual short-term memory (VSTM) experiments. Experiment 1 used a balanced memory array, with one color stimulus in each hemifield, followed by a retention interval and a central probe, at the fixation point that designated the target stimulus in memory about which to make a…

  1. The Episodic Engram Transformed: Time Reduces Retrieval-Related Brain Activity but Correlates It with Memory Accuracy

    ERIC Educational Resources Information Center

    Furman, Orit; Mendelsohn, Avi; Dudai, Yadin

    2012-01-01

    We took snapshots of human brain activity with fMRI during retrieval of realistic episodic memory over several months. Three groups of participants were scanned during a memory test either hours, weeks, or months after viewing a documentary movie. High recognition accuracy after hours decreased after weeks and remained at similar levels after…

  2. Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities

    SciTech Connect

    JULYK, L.J.

    1999-09-22

    This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

  3. Maladaptive Plasticity in Aphasia: Brain Activation Maps Underlying Verb Retrieval Errors.

    PubMed

    Spielmann, Kerstin; Durand, Edith; Marcotte, Karine; Ansaldo, Ana Inés

    2016-01-01

    Anomia, or impaired word retrieval, is the most widespread symptom of aphasia, an acquired language impairment secondary to brain damage. In the last decades, functional neuroimaging techniques have enabled studying the neural basis underlying anomia and its recovery. The present study aimed to explore maladaptive plasticity in persistent verb anomia, in three male participants with chronic nonfluent aphasia. Brain activation maps associated with semantic verb paraphasia occurring within an oral picture-naming task were identified with an event-related fMRI paradigm. These maps were compared with those obtained in our previous study examining adaptive plasticity (i.e., successful verb naming) in the same participants. The results show that activation patterns related to semantic verb paraphasia and successful verb naming comprise a number of common areas, contributing to both maladaptive and adaptive neuroplasticity mechanisms. This finding suggests that the segregation of brain areas provides only a partial view of the neural basis of verb anomia and successful verb naming. Therefore, it indicates the importance of network approaches which may better capture the complexity of maladaptive and adaptive neuroplasticity mechanisms in anomia recovery. PMID:27429808

  4. Maladaptive Plasticity in Aphasia: Brain Activation Maps Underlying Verb Retrieval Errors

    PubMed Central

    Durand, Edith; Marcotte, Karine; Ansaldo, Ana Inés

    2016-01-01

    Anomia, or impaired word retrieval, is the most widespread symptom of aphasia, an acquired language impairment secondary to brain damage. In the last decades, functional neuroimaging techniques have enabled studying the neural basis underlying anomia and its recovery. The present study aimed to explore maladaptive plasticity in persistent verb anomia, in three male participants with chronic nonfluent aphasia. Brain activation maps associated with semantic verb paraphasia occurring within an oral picture-naming task were identified with an event-related fMRI paradigm. These maps were compared with those obtained in our previous study examining adaptive plasticity (i.e., successful verb naming) in the same participants. The results show that activation patterns related to semantic verb paraphasia and successful verb naming comprise a number of common areas, contributing to both maladaptive and adaptive neuroplasticity mechanisms. This finding suggests that the segregation of brain areas provides only a partial view of the neural basis of verb anomia and successful verb naming. Therefore, it indicates the importance of network approaches which may better capture the complexity of maladaptive and adaptive neuroplasticity mechanisms in anomia recovery. PMID:27429808

  5. Chronic enhancement of CREB activity in the hippocampus interferes with the retrieval of spatial information

    PubMed Central

    Viosca, Jose; Malleret, Gaël; Bourtchouladze, Rusiko; Benito, Eva; Vronskava, Svetlana; Kandel, Eric R.; Barco, Angel

    2009-01-01

    The activation of cAMP-responsive element-binding protein (CREB)-dependent gene expression is thought to be critical for the formation of different types of long-term memory. To explore the consequences of chronic enhancement of CREB function on spatial memory in mammals, we examined spatial navigation in bitransgenic mice that express in a regulated and restricted manner a constitutively active form of CREB, VP16-CREB, in forebrain neurons. We found that chronic enhancement of CREB activity delayed the acquisition of an allocentric strategy to solve the hidden platform task. The ability to turn on and off transgene expression allowed us to dissect the role of CREB in dissociable memory processes. In mice in which transgene expression was turned on during memory acquisition, turning off the transgene re-established the access to the memory trace, whereas in mice in which transgene expression was turned off during acquisition, turning on the transgene impaired memory expression in a reversible manner, indicating that CREB enhancement specifically interfered with the retrieval of spatial information. The defects on spatial navigation in mice with chronic enhancement of CREB function were not corrected by conditions that increased further CREB-dependent activation of hippocampal memory systems, such as housing in an enriched environment. These results along with previous findings in CREB-deficient mutants indicate that the relationship of CREB-mediated plasticity to spatial memory is an inverted-U function, and that optimal learning in the water maze requires accurate regulation of this pathway. PMID:19237642

  6. Encoding and Retrieving Faces and Places: Distinguishing Process- and Stimulus-Specific Differences in Brain Activity

    PubMed Central

    Prince, Steven E.; Dennis, Nancy A.; Cabeza, Roberto

    2009-01-01

    Among the most fundamental issues in cognitive neuroscience is how the brain may be organized into process-specific and stimulus-specific regions. In the episodic memory domain, most functional neuroimaging studies have focused on the former dimension, typically investigating the neural correlates of various memory processes. Thus, there is little information about what role stimulus-specific brain regions play in successful memory processes. To address this issue, the present event-related fMRI study used a factorial design to focus on the role of stimulus-specific brain regions, such as the fusiform face area (FFA) and parahippocampal place area (PPA) in successful encoding and retrieval processes. Searching within regions sensitive to faces or places, we identified areas similarly involved in encoding and retrieval, as well as areas differentially involved in encoding or retrieval. Finally, we isolated regions associated with successful memory, regardless of stimulus and process type. There were three main findings. Within face sensitive regions, anterior medial PFC and right FFA displayed equivalent encoding and retrieval success processes whereas left FFA was associated with successful encoding rather than retrieval. Within place sensitive regions, left PPA displayed equivalent encoding and retrieval success processes whereas right PPA was associated with successful encoding rather than retrieval. Finally, medial temporal and prefrontal regions were associated with general memory success, regardless of stimulus or process type. Taken together, our results clarify the contribution of different brain regions to stimulus- and process-specific episodic memory mechanisms. PMID:19524092

  7. How does a child solve 7 + 8? Decoding brain activity patterns associated with counting and retrieval strategies.

    PubMed

    Cho, Soohyun; Ryali, Srikanth; Geary, David C; Menon, Vinod

    2011-09-01

    Cognitive development and learning are characterized by diminished reliance on effortful procedures and increased use of memory-based problem solving. Here we identify the neural correlates of this strategy shift in 7-9-year-old children at an important developmental period for arithmetic skill acquisition. Univariate and multivariate approaches were used to contrast brain responses between two groups of children who relied primarily on either retrieval or procedural counting strategies. Children who used retrieval strategies showed greater responses in the left ventrolateral prefrontal cortex; notably, this was the only brain region which showed univariate differences in signal intensity between the two groups. In contrast, multivariate analysis revealed distinct multivoxel activity patterns in bilateral hippocampus, posterior parietal cortex and left ventrolateral prefrontal cortex regions between the two groups. These results demonstrate that retrieval and counting strategies during early learning are characterized by distinct patterns of activity in a distributed network of brain regions involved in arithmetic problem solving and controlled retrieval of arithmetic facts. Our findings suggest that the reorganization and refinement of neural activity patterns in multiple brain regions plays a dominant role in the transition to memory-based arithmetic problem solving. Our findings further demonstrate how multivariate approaches can provide novel insights into fine-scale developmental changes in the brain. More generally, our study illustrates how brain imaging and developmental research can be integrated to investigate fundamental aspects of neurocognitive development. PMID:21884315

  8. New Combined L-band Active/Passive Soil Moisture Retrieval Algorithm Optimized for Argentine Plains

    NASA Astrophysics Data System (ADS)

    Bruscantini, C. A.; Grings, F. M.; Salvia, M.; Ferrazzoli, P.; Karszenbaum, H.

    2015-12-01

    The ability of L-band passive microwave satellite observations to provide soil moisture (mv) measurements is well known. Despite its high sensitivity to near-surface mv, radiometric technology suffers from having a relatively low spatial resolution. Conversely active microwave observations, although their finer resolution, are difficult to be interpreted for mv content due to the confounding effects of vegetation and roughness. There have been and there are strong motivations for the realization of satellite missions that carry passive and active microwave instruments on board. This has also led to important contributions in algorithm development. In this line of work, NASA-CONAE SAC-D/Aquarius mission had on board an L band radiometer and scatterometer. This was followed by the launch of NASA SMAP mission (Soil Moisture Active Passive), as well as several airborne campaigns that provide active and passive measurements. Within this frame, a new combined active/passive mv retrieval algorithm is proposed by deriving an analytical expression of brightness temperature and radar backscattering relation using explicit semi-empirical models. Simple models (i.e. that can be easily inverted and have relatively low amount of ancillary parameters) were selected: ω-τ model (Jackson et al., 1982, Water Resources Research) and radar-only model (Narvekar et al., 2015, IEEE Transactions on Geoscience and Remote Sensing). A major challenge involves coupling the active and passive models to be consistent with observations. Coupling equations can be derived using theoretical active/passive high-order radiative transfer models, such as 3D Numerical Method of Maxwell equations (Zhou et al., 2004, IEEE Transactions on Geoscience and Remote Sensing) and Tor Vergata (Ferrazzoli et al., 1995,Remote Sensing of Environment) models. In this context, different coupling equations can be optimized for different land covers using theoretical forward models with specific parametrization for each

  9. Soil Moisture Retrieval Through Changing Corn Using Active/Passive Microwave Remote Sensing

    NASA Technical Reports Server (NTRS)

    ONeill, P. E.; Joseph, A.; DeLannoy, G.; Lang, R.; Utku, C.; Kim, E.; Houser, P.; Gish, T.

    2003-01-01

    An extensive field experiment was conducted from May-early October, 2002 at the heavily instrumented USDA-ARS (U.S. Dept. of Agriculture-Agricultural Research Service) OPE3 (Optimizing Production Inputs for Economic and Environmental Enhancement) test site in Beltsville, MD to acquire data needed to address active/passive microwave algorithm, modeling, and ground validation issues for accurate soil moisture retrieval. During the experiment, a tower-mounted 1.4 GHz radiometer (Lrad) and a truck-mounted dual-frequency (1.6 and 4.75 GHz) radar system were deployed on the northern edge of the site. The soil in this portion of the field is a sandy loam (silt 23.5%, sand 60.3%, clay 16.1%) with a measured bulk density of 1.253 g/cu cm. Vegetation cover in the experiment consisted of a corn crop which was measured from just after planting on April 17, 2002 through senescence and harvesting on October 2. Although drought conditions prevailed during the summer, the corn yield was near average, with peak biomass reached in late July.

  10. Active imaging with the aids of polarization retrieve in turbid media system

    NASA Astrophysics Data System (ADS)

    Tao, Qiangqiang; Sun, Yongxuan; Shen, Fei; Xu, Qiang; Gao, Jun; Guo, Zhongyi

    2016-01-01

    We propose a novel active imaging based on the polarization retrieve (PR) method in turbid media system. In our simulations, the Monte Carlo (MC) algorithm has been used to investigate the scattering process between the incident photons and the scattering particles, and the visually concordant object but with different polarization characteristics in different regions, has been selected as the original target that is placed in the turbid media. Under linearly and circularly polarized illuminations, the simulation results demonstrate that the corresponding polarization properties can provide additional information for the imaging, and the contrast of the polarization image can also be enhanced greatly compared to the simplex intensity image in the turbid media. Besides, the polarization image adjusted by the PR method can further enhance the visibility and contrast. In addition, by PR imaging method, with the increasing particles' size in Mie's scale, the visibility can be enhanced, because of the increased forward scattering effect. In general, in the same circumstance, the circular polarization images can offer a better contrast and visibility than that of linear ones. The results indicate that the PR imaging method is more applicable to the scattering media system with relatively larger particles such as aerosols, heavy fog, cumulus, and seawater, as well as to biological tissues and blood media.

  11. Reinstatement of Individual Past Events Revealed by the Similarity of Distributed Activation Patterns during Encoding and Retrieval

    PubMed Central

    Wing, Erik A.; Ritchey, Maureen; Cabeza, Roberto

    2015-01-01

    Neurobiological memory models assume memory traces are stored in neocortex, with pointers in the hippocampus, and are then reactivated during retrieval, yielding the experience of remembering. Whereas most prior neuroimaging studies on reactivation have focused on the reactivation of sets or categories of items, the current study sought to identify cortical patterns pertaining to memory for individual scenes. During encoding, participants viewed pictures of scenes paired with matching labels (e.g., “barn,” “tunnel”), and, during retrieval, they recalled the scenes in response to the labels and rated the quality of their visual memories. Using representational similarity analyses, we interrogated the similarity between activation patterns during encoding and retrieval both at the item level (individual scenes) and the set level (all scenes). The study yielded four main findings. First, in occipitotemporal cortex, memory success increased with encoding-retrieval similarity (ERS) at the item level but not at the set level, indicating the reactivation of individual scenes. Second, in ventrolateral pFC, memory increased with ERS for both item and set levels, indicating the recapitulation of memory processes that benefit encoding and retrieval of all scenes. Third, in retrosplenial/posterior cingulate cortex, ERS was sensitive to individual scene information irrespective of memory success, suggesting automatic activation of scene contexts. Finally, consistent with neurobiological models, hippocampal activity during encoding predicted the subsequent reactivation of individual items. These findings show the promise of studying memory with greater specificity by isolating individual mnemonic representations and determining their relationship to factors like the detail with which past events are remembered. PMID:25313659

  12. Inactivation Or Inhibition Of Neuronal Activity In The Medial Prefrontal Cortex Largely Reduces Pup Retrieval And Grouping in Maternal Rats

    PubMed Central

    Febo, Marcelo; Felix-Ortiz, Ada C.; Johnson, Tehya R.

    2010-01-01

    Previous research suggests that the maternal medial prefrontal cortex (mPFC) may play a role in maternal care and that cocaine sensitization before pregnancy can affect neuronal activity within this region. The present work was carried out to test whether the mPFC does actually play a role in the expression of maternal behaviors in the rats and to understand what specific behaviors this cortical area may modulate. In the first experiment, tetrodotoxin (TTX) was used to chemically inactivate the mPFC during tests for maternal behavior latencies. Lactating rats were tested on postpartum day 7–9. The results of this first experiment indicate that there is a large effect of TTX-induced inactivation on retrieval behavior latencies. TTX nearly abolished the expression of maternal retrieval of pups without significantly impairing locomotor activity. In the second experiment, GABA-mediated inhibition was used to test maternal behavior latencies and durations of maternal and other behaviors in postpartum dams. In agreement with experiment 1, it was observed that dams capable of retrieving are rendered incapable by inhibition in the mPFC. GABA-mediated inhibition in the mPFC largely reduced retrieval without altering other indices of maternal care and non-specific behavior such as ambulation time, self-grooming, and inactivity. Moreover, in both experiments dams were able to establish contact with pups within seconds. The overall results indicate that the mPFC may play an active role in modulating maternal care, particularly retrieval behavior. External factors that affect the function of the frontal cortical site may result in significant impairments in maternal goal-directed behavior as reported in our earlier work. PMID:20156425

  13. Impact of changed positive and negative task-related brain activity on word-retrieval in aging

    PubMed Central

    Meinzer, M.; Seeds, L.; Flaisch, T.; Harnish, S.; Cohen, M.L.; McGregor, K.; Conway, T.; Benjamin, M.; Crosson, B.

    2010-01-01

    Previous functional imaging studies that compared activity patterns in older and younger adults during non-linguistic tasks found evidence for two phenomena: older participants usually show more pronounced task-related positive activity in the brain hemisphere that is not dominant for the task and less pronounced negative task-related activity in temporo-parietal and midline brain regions. The combined effects of these phenomena and the impact on word-retrieval, however, have not yet been assessed. We used functional magnetic resonance imaging to explore task-related positive (active task > baseline) and negative activity (baseline > active task) during semantic and phonemic verbal fluency tasks. Increased right-frontal positive activity during the semantic task and reduced negative activity in the right hemisphere during both tasks was associated with reduced performance in older subjects. No substantial relationship between changes in positive and negative activity was observed in the older participants, pointing towards two partially independent but potentially co-occurring processes. Underlying causes of the observed functional network inefficiency during word-retrieval in older adults need to be determined in the future. PMID:20696496

  14. Estimation of canopy attenuation for active/passive microwave soil moisture retrieval algorithms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper discusses the importance of the proper characterization of scattering and attenuation in trees needed for accurate retrieval of soil moisture in the presence of trees. Emphasis is placed on determining an accurate estimation of the propagation properties of a vegetation canopy using the c...

  15. An Activation-Based Model of Sentence Processing as Skilled Memory Retrieval

    ERIC Educational Resources Information Center

    Lewis, Richard L.; Vasishth, Shravan

    2005-01-01

    We present a detailed process theory of the moment-by-moment working-memory retrievals and associated control structure that subserve sentence comprehension. The theory is derived from the application of independently motivated principles of memory and cognitive skill to the specialized task of sentence parsing. The resulting theory construes…

  16. Brain Region-Specific Activity Patterns after Recent or Remote Memory Retrieval of Auditory Conditioned Fear

    ERIC Educational Resources Information Center

    Kwon, Jeong-Tae; Jhang, Jinho; Kim, Hyung-Su; Lee, Sujin; Han, Jin-Hee

    2012-01-01

    Memory is thought to be sparsely encoded throughout multiple brain regions forming unique memory trace. Although evidence has established that the amygdala is a key brain site for memory storage and retrieval of auditory conditioned fear memory, it remains elusive whether the auditory brain regions may be involved in fear memory storage or…

  17. Integrated Active Fire Retrievals and Biomass Burning Emissions Using Complementary Near-Coincident Ground, Airborne and Spaceborne Sensor Data

    NASA Technical Reports Server (NTRS)

    Schroeder, Wilfrid; Ellicott, Evan; Ichoku, Charles; Ellison, Luke; Dickinson, Matthew B.; Ottmar, Roger D.; Clements, Craig; Hall, Dianne; Ambrosia, Vincent; Kremens, Robert

    2013-01-01

    Ground, airborne and spaceborne data were collected for a 450 ha prescribed fire implemented on 18 October 2011 at the Henry W. Coe State Park in California. The integration of various data elements allowed near coincident active fire retrievals to be estimated. The Autonomous Modular Sensor-Wildfire (AMS) airborne multispectral imaging system was used as a bridge between ground and spaceborne data sets providing high quality reference information to support satellite fire retrieval error analyses and fire emissions estimates. We found excellent agreement between peak fire radiant heat flux data (less than 1% error) derived from near-coincident ground radiometers and AMS. Both MODIS and GOES imager active fire products were negatively influenced by the presence of thick smoke, which was misclassified as cloud by their algorithms, leading to the omission of fire pixels beneath the smoke, and resulting in the underestimation of their retrieved fire radiative power (FRP) values for the burn plot, compared to the reference airborne data. Agreement between airborne and spaceborne FRP data improved significantly after correction for omission errors and atmospheric attenuation, resulting in as low as 5 difference between AquaMODIS and AMS. Use of in situ fuel and fire energy estimates in combination with a collection of AMS, MODIS, and GOES FRP retrievals provided a fuel consumption factor of 0.261 kg per MJ, total energy release of 14.5 x 10(exp 6) MJ, and total fuel consumption of 3.8 x 10(exp 6) kg. Fire emissions were calculated using two separate techniques, resulting in as low as 15 difference for various species

  18. Analysis of soil moisture retrieval from airborne passive/active L-band sensor measurements in SMAPVEX 2012

    NASA Astrophysics Data System (ADS)

    Chen, Liang; Song, Hongting; Tan, Lei; Li, Yinan; Li, Hao

    2014-11-01

    Soil moisture is a key component in the hydrologic cycle and climate system. It is an important input parameter for many hydrologic and meteorological models. NASA'S upcoming Soil Moisture Active Passive (SMAP) mission, to be launched in October 2014, will address this need by utilizing passive and active microwave measurements at L-band, which will penetrate moderately dense canopies. In preparation for the SMAP mission, the Soil Moisture Validation Experiment 2012 (SMAPVEX12) was conducted from 6 June to 17 July 2012 in the Carment-Elm Creek area in Manitoba, Canada. Over a period of six weeks diverse land cover types ranging from agriculture over pasture and grassland to forested sites were re-visited several times a week. The Passive/Active L-band Sensor (PALS) provides radiometer products, vertically and horizontally polarized brightness temperatures, and radar products. Over the past two decades, successful estimation of soil moisture has been accomplished using passive and active L-band data. However, remaining uncertainties related to surface roughness and the absorption, scattering, and emission by vegetation must be resolved before soil moisture retrieval algorithms can be applied with known and acceptable accuracy using satellite observations. This work focuses on analyzing the Passive/Active L-band Sensor observations of sites covered during SMAPVEX12, investigating the observed data, parameterizing vegetation covered surface model, modeling inversion algorithm and analyzing observed soil moisture changes over the time period of six weeks. The data and analysis results from this study are aimed at increasing the accuracy and range of validity of SMAP soil moisture retrievals via enhancing the accuracy for soil moisture retrieval.

  19. Application of artificial neural networks for the soil moisture retrieval from active and passive microwave spaceborne sensors

    NASA Astrophysics Data System (ADS)

    Santi, Emanuele; Paloscia, Simonetta; Pettinato, Simone; Fontanelli, Giacomo

    2016-06-01

    Among the algorithms used for the retrieval of SMC from microwave sensors (both active, such as Synthetic Aperture Radar-SAR, and passive, radiometers), the artificial neural networks (ANN) represent the best compromise between accuracy and computation speed. ANN based algorithms have been developed at IFAC, and adapted to several radar and radiometric satellite sensors, in order to generate SMC products at a resolution varying from hundreds of meters to tens of kilometers according to the spatial scale of each sensor. These algorithms, which are based on the ANN techniques for inverting theoretical and semi-empirical models, have been adapted to the C- to Ka- band acquisitions from spaceborne radiometers (AMSR-E/AMSR2), SAR (Envisat/ASAR, Cosmo-SkyMed) and real aperture radar (MetOP ASCAT). Large datasets of co-located satellite acquisitions and direct SMC measurements on several test sites worldwide have been used along with simulations derived from forward electromagnetic models for setting up, training and validating these algorithms. An overall quality assessment of the obtained results in terms of accuracy and computational cost was carried out, and the main advantages and limitations for an operational use of these algorithms were evaluated. This technique allowed the retrieval of SMC from both active and passive satellite systems, with accuracy values of about 0.05 m3/m3 of SMC or better, thus making these applications compliant with the usual accuracy requirements for SMC products from space.

  20. Default network activation during episodic and semantic memory retrieval: A selective meta-analytic comparison.

    PubMed

    Kim, Hongkeun

    2016-01-01

    It remains unclear whether and to what extent the default network subregions involved in episodic memory (EM) and semantic memory (SM) processes overlap or are separated from one another. This study addresses this issue through a controlled meta-analysis of functional neuroimaging studies involving healthy participants. Various EM and SM task paradigms differ widely in the extent of default network involvement. Therefore, the issue at hand cannot be properly addressed without some control for this factor. In this regard, this study employs a two-stage analysis: a preliminary meta-analysis to select EM and SM task paradigms that recruit relatively extensive default network regions and a main analysis to compare the selected task paradigms. Based on a within-EM comparison, the default network contributed more to recollection/familiarity effects than to old/new effects, and based on a within-SM comparison, it contributed more to word/pseudoword effects than to semantic/phonological effects. According to a direct comparison of recollection/familiarity and word/pseudoword effects, each involving a range of default network regions, there were more overlaps than separations in default network subregions involved in these two effects. More specifically, overlaps included the bilateral posterior cingulate/retrosplenial cortex, left inferior parietal lobule, and left anteromedial prefrontal regions, whereas separations included only the hippocampal formation and the parahippocampal cortex region, which was unique to recollection/familiarity effects. These results indicate that EM and SM retrieval processes involving strong memory signals recruit extensive and largely overlapping default network regions and differ mainly in distinct contributions of hippocampus and parahippocampal regions to EM retrieval. PMID:26562053

  1. Global Weather States and Their Properties from Passive and Active Satellite Cloud Retrievals

    NASA Technical Reports Server (NTRS)

    Tselioudis, George; Rossow, William; Zhang, Yuanchong; Konsta, Dimitra

    2013-01-01

    In this study, the authors apply a clustering algorithm to International Satellite Cloud Climatology Project (ISCCP) cloud optical thickness-cloud top pressure histograms in order to derive weather states (WSs) for the global domain. The cloud property distribution within each WS is examined and the geographical variability of each WS is mapped. Once the global WSs are derived, a combination of CloudSat and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) vertical cloud structure retrievals is used to derive the vertical distribution of the cloud field within each WS. Finally, the dynamic environment and the radiative signature of the WSs are derived and their variability is examined. The cluster analysis produces a comprehensive description of global atmospheric conditions through the derivation of 11 WSs, each representing a distinct cloud structure characterized by the horizontal distribution of cloud optical depth and cloud top pressure. Matching those distinct WSs with cloud vertical profiles derived from CloudSat and CALIPSO retrievals shows that the ISCCP WSs exhibit unique distributions of vertical layering that correspond well to the horizontal structure of cloud properties. Matching the derived WSs with vertical velocity measurements shows a normal progression in dynamic regime when moving from the most convective to the least convective WS. Time trend analysis of the WSs shows a sharp increase of the fair-weather WS in the 1990s and a flattening of that increase in the 2000s. The fact that the fair-weather WS is the one with the lowest cloud radiative cooling capability implies that this behavior has contributed excess radiative warming to the global radiative budget during the 1990s.

  2. The Effect of Retrieval Focus and Emotional Valence on the Inferior Frontal Cortex Activity during Autobiographical Recollection

    PubMed Central

    Denkova, Ekaterina; Dolcos, Sanda; Dolcos, Florin

    2013-01-01

    Although available evidence points to a role of the inferior frontal cortex (IFC) in both emotion processing and autobiographical memory (AM) recollection, it is unclear what the role of this region is in emotional AM recollection. The present study investigated whether IFC activity can be influenced by manipulations of the retrieval focus (emotional vs. non-emotional) and whether this influence is similar for AMs with positive and negative emotional valence. Participants were asked to focus either on emotional (Emotion condition) or on non-emotional contextual (Context condition) details during the elaboration of positive and negative AMs, while fMRI data were collected. The study yielded two main findings: (1) Focusing on Emotion compared to Context during AM recollection was associated with increased activity in bilateral IFC, for positive AMs, whereas negative AMs produced similarly high IFC activity during Emotion and Context conditions; (2) There was a hemispheric dissociation in the IFC linked to the experiencing of emotion and the focus of AM recollection, such that the left IFC activity correlated positively with the subjective re-experience of emotion during the Emotion condition, whereas the right IFC activity correlated negatively with the subjective re-experience of emotion during the Context condition, for both positive and negative AMs. Overall, the present findings suggest that IFC’s involvement during the recollection of emotional AMs is susceptible to manipulations of the retrieval focus only in the case of positive AMs, and that this region plays a role in both the enhancement and inhibition of emotional experience during AM recollection. PMID:24379766

  3. Same Modulation but Different Starting Points: Performance Modulates Age Differences in Inferior Frontal Cortex Activity during Word-Retrieval

    PubMed Central

    Meinzer, Marcus; Flaisch, Tobias; Seeds, Lauren; Harnish, Stacy; Antonenko, Daria; Witte, Veronica; Lindenberg, Robert; Crosson, Bruce

    2012-01-01

    The neural basis of word-retrieval deficits in normal aging has rarely been assessed and the few previous functional imaging studies found enhanced activity in right prefrontal areas in healthy older compared to younger adults. However, more pronounced right prefrontal recruitment has primarily been observed during challenging task conditions. Moreover, increased task difficulty may result in enhanced activity in the ventral inferior frontal gyrus (vIFG) bilaterally in younger participants as well. Thus, the question arises whether increased activity in older participants represents an age-related phenomenon or reflects task difficulty effects. In the present study, we manipulated task difficulty during overt semantic and phonemic word-generation and used functional magnetic resonance imaging to assess activity patterns in the vIFG in healthy younger and older adults (N = 16/group; mean age: 24 vs. 69 years). Both groups produced fewer correct responses during the more difficult task conditions. Overall, older participants produced fewer correct responses and showed more pronounced task-related activity in the right vIFG. However, increased activity during the more difficult conditions was found in both groups. Absolute degree of activity was correlated with performance across groups, tasks and difficulty levels. Activity modulation (difficult vs. easy conditions) was correlated with the respective drop in performance across groups and tasks. In conclusion, vIFG activity levels and modulation of activity were mediated by performance accuracy in a similar way in both groups. Group differences in the right vIFG activity were explained by performance accuracy which needs to be considered in future functional imaging studies of healthy and pathological aging. PMID:22438970

  4. Same modulation but different starting points: performance modulates age differences in inferior frontal cortex activity during word-retrieval.

    PubMed

    Meinzer, Marcus; Flaisch, Tobias; Seeds, Lauren; Harnish, Stacy; Antonenko, Daria; Witte, Veronica; Lindenberg, Robert; Crosson, Bruce

    2012-01-01

    The neural basis of word-retrieval deficits in normal aging has rarely been assessed and the few previous functional imaging studies found enhanced activity in right prefrontal areas in healthy older compared to younger adults. However, more pronounced right prefrontal recruitment has primarily been observed during challenging task conditions. Moreover, increased task difficulty may result in enhanced activity in the ventral inferior frontal gyrus (vIFG) bilaterally in younger participants as well. Thus, the question arises whether increased activity in older participants represents an age-related phenomenon or reflects task difficulty effects. In the present study, we manipulated task difficulty during overt semantic and phonemic word-generation and used functional magnetic resonance imaging to assess activity patterns in the vIFG in healthy younger and older adults (N = 16/group; mean age: 24 vs. 69 years). Both groups produced fewer correct responses during the more difficult task conditions. Overall, older participants produced fewer correct responses and showed more pronounced task-related activity in the right vIFG. However, increased activity during the more difficult conditions was found in both groups. Absolute degree of activity was correlated with performance across groups, tasks and difficulty levels. Activity modulation (difficult vs. easy conditions) was correlated with the respective drop in performance across groups and tasks. In conclusion, vIFG activity levels and modulation of activity were mediated by performance accuracy in a similar way in both groups. Group differences in the right vIFG activity were explained by performance accuracy which needs to be considered in future functional imaging studies of healthy and pathological aging. PMID:22438970

  5. Brain-derived neurotrophic factor val66met polymorphism and hippocampal activation during episodic encoding and retrieval tasks.

    PubMed

    Dennis, Nancy A; Cabeza, Roberto; Need, Anna C; Waters-Metenier, Sheena; Goldstein, David B; LaBar, Kevin S

    2011-09-01

    Brain-derived neurotrophic factor (BDNF) is a neurotrophin which has been shown to regulate cell survival and proliferation, as well as synaptic growth and hippocampal long-term potentiation. A naturally occurring single nucleotide polymorphism in the human BDNF gene (val66met) has been associated with altered intercellular trafficking and regulated secretion of BDNF in met compared to val carriers. Additionally, previous studies have found a relationship between the BDNF val66met genotype and functional activity in the hippocampus during episodic and working memory tasks in healthy young adults. Specifically, studies have found that met carriers exhibit both poorer performance and reduced neural activity within the medial temporal lobe (MTL) when performing episodic memory tasks. However, these studies have not been well replicated and have not considered the role of behavioral differences in the interpretation of neural differences. The current study sought to control for cognitive performance in investigating the role of the BDNF val66met genotype on neural activity associated with episodic memory. Across item and relational memory tests, met carriers exhibited increased MTL activation during both encoding and retrieval stages, compared to noncarriers. The results suggest that met carriers are able to recruit MTL activity to support successful memory processes, and reductions in cognitive performance observed in prior studies are not a ubiquitous effect associated with variants of the BDNF val66met genotype. PMID:20865733

  6. A real-time framework for fast data retrieval in an image database of volcano activity scenarios

    NASA Astrophysics Data System (ADS)

    Aliotta, Marco Antonio; Cannata, Andrea; Cassisi, Carmelo; Ciancitto, Francesco; Montalto, Placido; Prestifilippo, Michele

    2015-04-01

    Explosive Activity at Stromboli Volcano (Aeolian Islands) is continuously monitored by INGV-OE in order to analyze its eruptive dynamics and specific scenarios. In particular, the images acquired from thermal cameras represent a big collection of data. In order to extract useful information from thermal image sequences, we need an efficient way to explore and retrieve information from a huge amount of data. In this work, a novel framework capable of fast data retrieval, using the "metric space" concept, is shown. In the light of it, we implemented an indexing algorithm related to similarity laws. The focal point is finding objects of a set that are "close" in relation to a given query, according to a similarity criterion. In order to perform this task, we performed morphological image processing techniques to each video frame, in order to map the shape area of each explosion into a closed curve, representing the explosion contour itself. In order to constitute a metric space, we chose a certain number of features obtained from parameters related to this closed curve and used them as objects of this metric space where similarity can be evaluated, using an appropriate "metric" function to calculate the distances. Unfortunately, this approach has to deal with an intrinsic issue involving the complexity and the number of distance functions to be calculated on a large amount of data. To overcome this drawback, we used a novel abstract data structure called "K-Pole Tree", having the property of minimizing the number of distances to be calculated among objects. Our method allows for fast retrieval of similar objects using an euclidean distance function among the features of the metric space. Thus, we can cluster explosions related to different kinds of volcanic activity, using "pivot" items. For example, given a known image sequence related to a particular type of explosion, it is possible to quickly and easily find all the image sequences that contain only similar

  7. Analysis of coherent activity between retrosplenial cortex, hippocampus, thalamus, and anterior cingulate cortex during retrieval of recent and remote context fear memory.

    PubMed

    Corcoran, Kevin A; Frick, Brendan J; Radulovic, Jelena; Kay, Leslie M

    2016-01-01

    Memory for contextual fear conditioning relies upon the retrosplenial cortex (RSC) regardless of how long ago conditioning occurred, whereas areas connected to the RSC, such as the dorsal hippocampus (DH) and anterior cingulate cortex (ACC) appear to play time-limited roles. To better understand whether these brain regions functionally interact during memory processing and how the passage of time affects these interactions, we simultaneously recorded local field potentials (LFPs) from these three regions as well as anterior dorsal thalamus (ADT), which provides one of the strongest inputs to RSC, and measured coherence of oscillatory activity within the theta (4-12Hz) and gamma (30-80Hz) frequency bands. We identified changes of theta coherence related to encoding, retrieval, and extinction of context fear, whereas changes in gamma coherence were restricted to fear extinction. Specifically, exposure to a novel context and retrieval of recently acquired fear conditioning memory were associated with increased theta coherence between RSC and all three other structures. In contrast, RSC-DH and RSC-ADT theta coherence were decreased in mice that successfully retrieved, relative to mice that failed to retrieve, remote memory. Greater RSC-ADT theta and gamma coherence were observed during recent, compared to remote, extinction of freezing responses. Thus, the degree of coherence between RSC and connected brain areas may predict and contribute to context memory retrieval and retrieval-related phenomena such as fear extinction. Importantly, although theta coherence in this circuit increases during memory encoding and retrieval of recent memory, failure to decrease RSC-DH theta coherence might be linked to retrieval deficit in the long term, and possibly contribute to aberrant memory processing characteristic of neuropsychiatric disorders. PMID:26691782

  8. Prefrontal cortex activation during story encoding/retrieval: a multi-channel functional near-infrared spectroscopy study

    PubMed Central

    Basso Moro, Sara; Cutini, Simone; Ursini, Maria Laura; Ferrari, Marco; Quaresima, Valentina

    2013-01-01

    Encoding, storage and retrieval constitute three fundamental stages in information processing and memory. They allow for the creation of new memory traces, the maintenance and the consolidation of these traces over time, and the access and recover of the stored information from short or long-term memory. Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures concentration changes of oxygenated-hemoglobin (O2Hb) and deoxygenated-hemoglobin (HHb) in cortical microcirculation blood vessels by means of the characteristic absorption spectra of hemoglobin in the near-infrared range. In the present study, we monitored, using a 16-channel fNIRS system, the hemodynamic response during the encoding and retrieval processes (EP and RP, respectively) over the prefrontal cortex (PFC) of 13 healthy subjects (27.2 ± 2.6 years) while were performing the “Logical Memory Test” (LMT) of the Wechsler Memory Scale. A LMT-related PFC activation was expected; specifically, it was hypothesized a neural dissociation between EP and RP. The results showed a heterogeneous O2Hb/HHb response over the mapped area during the EP and the RP, with a O2Hb progressive and prominent increment in ventrolateral PFC (VLPFC) since the beginning of the EP. During the RP a broader activation, including the VLPFC, the dorsolateral PFC and the frontopolar cortex, was observed. This could be explained by the different contributions of the PFC regions in the EP and the RP. Considering the fNIRS applicability for the hemodynamic monitoring during the LMT performance, this study has demonstrated that fNIRS could be utilized as a valuable clinical diagnostic tool, and that it has the potential to be adopted in patients with cognitive disorders or slight working memory deficits. PMID:24427131

  9. Prefrontal cortex activation during story encoding/retrieval: a multi-channel functional near-infrared spectroscopy study.

    PubMed

    Basso Moro, Sara; Cutini, Simone; Ursini, Maria Laura; Ferrari, Marco; Quaresima, Valentina

    2013-01-01

    Encoding, storage and retrieval constitute three fundamental stages in information processing and memory. They allow for the creation of new memory traces, the maintenance and the consolidation of these traces over time, and the access and recover of the stored information from short or long-term memory. Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures concentration changes of oxygenated-hemoglobin (O2Hb) and deoxygenated-hemoglobin (HHb) in cortical microcirculation blood vessels by means of the characteristic absorption spectra of hemoglobin in the near-infrared range. In the present study, we monitored, using a 16-channel fNIRS system, the hemodynamic response during the encoding and retrieval processes (EP and RP, respectively) over the prefrontal cortex (PFC) of 13 healthy subjects (27.2 ± 2.6 years) while were performing the "Logical Memory Test" (LMT) of the Wechsler Memory Scale. A LMT-related PFC activation was expected; specifically, it was hypothesized a neural dissociation between EP and RP. The results showed a heterogeneous O2Hb/HHb response over the mapped area during the EP and the RP, with a O2Hb progressive and prominent increment in ventrolateral PFC (VLPFC) since the beginning of the EP. During the RP a broader activation, including the VLPFC, the dorsolateral PFC and the frontopolar cortex, was observed. This could be explained by the different contributions of the PFC regions in the EP and the RP. Considering the fNIRS applicability for the hemodynamic monitoring during the LMT performance, this study has demonstrated that fNIRS could be utilized as a valuable clinical diagnostic tool, and that it has the potential to be adopted in patients with cognitive disorders or slight working memory deficits. PMID:24427131

  10. Retrieval options study

    SciTech Connect

    Not Available

    1980-03-01

    This Retrieval Options Study is part of the systems analysis activities of the Office of Nuclear Waste Isolation to develop the scientific and technological bases for radioactive waste repositories in various geologic media. The study considers two waste forms, high level waste and spent fuel, and defines various classes of waste retrieval and recovery. A methodology and data base are developed which allow the relative evaluation of retrieval and recovery costs and the following technical criteria: safety; technical feasibility; ease of retrieval; probable intact retrieval time; safeguards; monitoring; criticality; and licensability. A total of 505 repository options are defined and the cost and technical criteria evaluated utilizing a combination of facts and engineering judgments. The repositories evaluated are selected combinations of the following parameters: Geologic Media (salt, granite, basalt, shale); Retrieval Time after Emplacement (5 and 25 years); Emplacement Design (nominal hole, large hole, carbon steel canister, corrosion resistant canister, backfill in hole, nominal sleeves, thick wall sleeves); Emplacement Configuration (single vertical, multiple vertical, single horizontal, multiple horizontal, vaults; Thermal Considerations; (normal design, reduced density, once-through ventilation, recirculated ventilation); Room Backfill; (none, run-of-mine, early, 5 year delay, 25 year delay, decommissioned); and Rate of Retrieval; (same as emplacement, variably slower depending on repository/canister condition).

  11. Using Airborne High Spectral Resolution Lidar Data to Evaluate Combined Active Plus Passive Retrievals of Aerosol Extinction Profiles

    NASA Technical Reports Server (NTRS)

    Burton, S. P.; Ferrare, R. A.; Kittaka, C.; Hostetler, C. A.; Hair, J. W.; Obland, M. D.; Rogers, R. R.; Cook, A. L.; Haper, D. B.

    2008-01-01

    Aerosol extinction profiles are derived from backscatter data by constraining the retrieval with column aerosol optical thickness (AOT), for example from coincident MODIS observations and without reliance on a priori assumptions about aerosol type or optical properties. The backscatter data were acquired with the NASA Langley High Spectral Resolution Lidar (HSRL). The HSRL also simultaneously measures extinction independently, thereby providing an ideal data set for evaluating the constrained retrieval of extinction from backscatter. We will show constrained extinction retrievals using various sources of column AOT, and examine comparisons with the HSRL extinction measurements and with a similar retrieval using data from the CALIOP lidar on the CALIPSO satellite.

  12. Antimicrobial Activity of Marine Bacterial Symbionts Retrieved from Shallow Water Hydrothermal Vents.

    PubMed

    Eythorsdottir, Arnheidur; Omarsdottir, Sesselja; Einarsson, Hjorleifur

    2016-06-01

    Marine sponges and other sessile macro-organisms were collected at a shallow water hydrothermal site in Eyjafjörður, Iceland. Bacteria were isolated from the organisms using selective media for actinomycetes, and the isolates were screened for antimicrobial activity. A total of 111 isolates revealed antimicrobial activity displaying different antimicrobial patterns which indicates production of various compounds. Known test strains were grown in the presence of ethyl acetate extracts from one selected isolate, and a clear growth inhibition of Staphylococcus aureus was observed down to 0.1 % extract concentration in the medium. Identification of isolates shows different species of Actinobacteria with Streptomyces sp. playing the largest role, but also members of Bacilli, Alphaproteobacteria and Gammaproteobacteria. Sponges have an excellent record regarding production of bioactive compounds, often involving microbial symbionts. At the hydrothermal vents, however, the majority of active isolates originated from other invertebrates such as sea anemones or algae. The results indicate that antimicrobial assays involving isolates in full growth can detect activity not visible by other methods. The macro-organisms inhabiting the Eyjafjörður hydrothermal vent area host diverse microbial species in the phylum Actinobacteria with antimicrobial activity, and the compounds responsible for the activity will be subject to further research. PMID:27147438

  13. In vitro activation of human fibroblasts by retrieved titanium alloy wear debris.

    PubMed

    Manlapaz, M; Maloney, W J; Smith, R L

    1996-05-01

    Titanium-aluminum-vanadium wear particles isolated from the soft-issue membrane of a failed total hip arthroplasty were added to human fibroblasts in cell culture. The cellular response to particle challenge was determined by assaying for levels of interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, prostaglandin E2, basic fibroblast growth factor, platelet-derived growth factor-AB, and transforming growth factor-beta. Collagenase and gelatinase activities were analyzed by zymography and [3H]collagen degradation. Cell viability was assessed by measuring the uptake of [3H]thymidine. Over the range of particle concentrations tested, cell viability, as demonstrated by [3H]thymidine uptake, remained unaffected. Fibroblasts exhibited a dose-dependent release of interleukin-6 in response to exposure to titanium-aluminum-vanadium particles. At 6 and 48 hours, the highest concentration of titanium alloy particles (0.189% [vol/vol]) resulted in 7-fold and 16-fold increases in interleukin-6 release, respectively, when compared with negative controls. Neither interleukin-1 beta nor tumor necrosis factor-alpha was detected in the culture medium at any particle concentration tested for both dermal and foreskin fibroblasts. The pattern of prostaglandin E2 release by fibroblasts mirrored the pattern of interleukin-6 release. Fibroblasts exposed to the highest concentration of titanium alloy particles showed an increase in collagenase activity, starting at 12 hours. When medium samples were treated with amino phenylmercuric acetate to activate latent enzymes, a statistically significant increase in collagenase activity was observed as early as 6 hours (p < 0.001). Substrate gel analysis of medium from fibroblasts stimulated by high particle concentrations also showed an increase in gelatinolytic activity when compared with unstimulated controls. Analysis of medium samples for growth factors showed an increase in basic fibroblast growth factor at low particle

  14. The Roles of Spreading Activation and Retrieval Mode in Producing False Recognition in the DRM Paradigm

    ERIC Educational Resources Information Center

    Meade, Michelle L.; Watson, Jason M.; Balota, David A.; Roediger, Henry L., III

    2007-01-01

    The nature of persisting spreading activation from list presentation in eliciting false recognition in the Deese-Roediger-McDermott (DRM) paradigm was examined in two experiments. We compared the time course of semantic priming in the lexical decision task (LDT) and false alarms in speeded recognition under identical study and test conditions. The…

  15. Different Brain Activities Predict Retrieval Success during Emotional and Semantic Encoding

    ERIC Educational Resources Information Center

    Padovani, Tullia; Koenig, Thomas; Brandeis, Daniel; Perrig, Walter J.

    2011-01-01

    There is an increasing line of evidence supporting the idea that the formation of lasting memories involves neural activity preceding stimulus presentation. Following this line, we presented words in an incidental learning setting and manipulated the prestimulus state by asking the participants to perform either an emotional (neutral or emotional)…

  16. The soil moisture active passive experiments (SMAPEx): Towards soil moisture retrieval from the SMAP mission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NASA’s Soil Moisture Active Passive (SMAP) mission, scheduled for launch in 2014, will carry the first combined L-band radar and radiometer system with the objective of mapping near surface soil moisture and freeze/thaw state globally at near-daily time step (2-3 days). SMAP will provide three soil ...

  17. Chronic Enhancement of CREB Activity in the Hippocampus Interferes with the Retrieval of Spatial Information

    ERIC Educational Resources Information Center

    Viosca, Jose; Malleret, Gael; Bourtchouladze, Rusiko; Benito, Eva; Vronskava, Svetlana; Kandel, Eric R.; Barco, Angel

    2009-01-01

    The activation of cAMP-responsive element-binding protein (CREB)-dependent gene expression is thought to be critical for the formation of different types of long-term memory. To explore the consequences of chronic enhancement of CREB function on spatial memory in mammals, we examined spatial navigation in bitransgenic mice that express in a…

  18. The Role of Phonological Activation in the Visual Semantic Retrieval of Chinese Characters

    ERIC Educational Resources Information Center

    Guo, Taomei; Peng, Danling; Liu, Ying

    2005-01-01

    The Stroop paradigm was used to examine the role of phonological activation in semantic access and its development in reading Chinese characters. Subjects (age 7-23 years) of different reading ability were asked to name the display color of Chinese characters. The characters were displayed in four different colors: red, yellow, blue and green.…

  19. Immediate-Early Gene Transcriptional Activation in Hippocampus Ca1 and Ca3 Does Not Accurately Reflect Rapid, Pattern Completion-Based Retrieval of Context Memory

    ERIC Educational Resources Information Center

    Pevzner, Aleksandr; Guzowski, John F.

    2015-01-01

    No studies to date have examined whether immediate-early gene (IEG) activation is driven by context memory recall. To address this question, we utilized the context preexposure facilitation effect (CPFE) paradigm. In CPFE, animals acquire contextual fear conditioning through hippocampus-dependent rapid retrieval of a previously formed contextual…

  20. Single-Center Experience and 1-Year Follow-up Results of 'Sandwich Technique' in the Management of Common Iliac Artery Aneurysms During EVAR

    SciTech Connect

    Ricci, Carmelo; Ceccherini, Claudio Cini, Marco; Vigni, Francesco; Leonini, Sara; Tommasino, Giulio; Muzzi, Luigi; Tucci, Enrico; Benvenuti, Antonio; Neri, Eugenio

    2012-10-15

    Purpose: Abdominal aortic aneurysm (AAA) accompanied by common iliac artery (CIA) aneurysms requires a more demanding procedure owing to the difficulties in obtaining an adequate distal landing zone for the stent-graft limb(s), a potential site of endoleak. The 'sandwich technique' is a procedure to increase EVAR feasibility in the setting of adverse or challenging CIA anatomy. Its main advantages include no restrictions in terms of CIA diameter or length or internal iliac artery (IIA) diameter, no need to wait for a specific stent-graft. Our purpose is to describe our single-center experience and one year follow-up results of this new procedure. Materials and Methods: From April 2009 to June 2010, the sandwich technique was performed in our institution in 7 patients treated for AAA and unilateral CIA aneurysms (n. 5) or bilateral CIA aneurysms (n. 2). Inclusion criteria were the presence of unilateral or bilateral CIA aneurysm (independently from its diameter), IIA artery measuring up to 9 mm in its maximum diameter, not dilatation of IIA and EIA. Results: The mean follow-up length was 15 months (range: 14-20 months). All stent-implanted iliac branches remained patent on 1 year follow-up and IIA flow was preserved. None of the patients had symptoms of pelvic ischemia. CT scan follow-up showed aneurysm shrinkage in five patients, without any sign of endoleaks in all cases. Conclusions: In selected cases, the 'sandwich technique' showed good outcomes confirming to be a safe and easy to perform way to overcome anatomical constraints and expanding the limits of EVAR.

  1. Structural Dissection of Crotalicidin, a Rattlesnake Venom Cathelicidin, Retrieves a Fragment with Antimicrobial and Antitumor Activity.

    PubMed

    Falcao, Claudio Borges; Pérez-Peinado, Clara; de la Torre, Beatriz G; Mayol, Xavier; Zamora-Carreras, Héctor; Jiménez, M Ángeles; Rádis-Baptista, Gandhi; Andreu, David

    2015-11-12

    In silico dissection of crotalicidin (Ctn), a cathelicidin from a South American pit viper, yielded fragments Ctn[1-14] and Ctn[15-34], which were tested to ascertain to what extent they reproduced the structure and activity of the parent peptide. NMR data showing Ctn to be α-helical at the N-terminus and unstructured at the C-terminus were matched by similar data from the fragments. The peptides were tested against Gram-positive and -negative bacteria and for toxicity against both tumor and healthy cells. Despite its amphipathic α-helical structure, Ctn[1-14] was totally inert toward bacteria or eukaryotic cells. In contrast, unstructured Ctn[15-34] replicated the activity of parent Ctn against Gram-negative bacteria and tumor cells while being significantly less toxic toward eukaryotic cells. This selectivity for bacteria and tumor cells, plus a stability to serum well above that of Ctn, portrays Ctn[15-34] as an appealing candidate for further development as an anti-infective or antitumor lead. PMID:26465972

  2. KCNQ/Kv7 channel activator flupirtine protects against acute stress-induced impairments of spatial memory retrieval and hippocampal LTP in rats.

    PubMed

    Li, C; Huang, P; Lu, Q; Zhou, M; Guo, L; Xu, X

    2014-11-01

    Spatial memory retrieval and hippocampal long-term potentiation (LTP) are impaired by stress. KCNQ/Kv7 channels are closely associated with memory and the KCNQ/Kv7 channel activator flupirtine represents neuroprotective effects. This study aims to test whether KCNQ/Kv7 channel activation prevents acute stress-induced impairments of spatial memory retrieval and hippocampal LTP. Rats were placed on an elevated platform in the middle of a bright room for 30 min to evoke acute stress. The expression of KCNQ/Kv7 subunits was analyzed at 1, 3 and 12 h after stress by Western blotting. Spatial memory was examined by the Morris water maze (MWM) and the field excitatory postsynaptic potential (fEPSP) in the hippocampal CA1 area was recorded in vivo. Acute stress transiently decreased the expression of KCNQ2 and KCNQ3 in the hippocampus. Acute stress impaired the spatial memory retrieval and hippocampal LTP, the KCNQ/Kv7 channel activator flupirtine prevented the impairments, and the protective effects of flupirtine were blocked by XE-991 (10,10-bis(4-Pyridinylmethyl)-9(10H)-anthracenone), a selective KCNQ channel blocker. Furthermore, acute stress decreased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) at Ser9 in the hippocampus, and flupirtine inhibited the reduction. These results suggest that the KCNQ/Kv7 channels may be a potential target for protecting both hippocampal synaptic plasticity and spatial memory retrieval from acute stress influences. PMID:25234320

  3. Golden Retrievers.

    ERIC Educational Resources Information Center

    Christensen, Deborah

    1999-01-01

    Provides a basic definition of metadata, including the usefulness of metatags for online information retrieval and documentation. Defines the elements of the Dublin Core, the next level of metadata. Discusses how librarians can take advantage of metadata. Describes the Gateway to Educational Materials (GEM) Project whose goal is to use metadata to…

  4. Immediate-early gene transcriptional activation in hippocampus CA1 and CA3 does not accurately reflect rapid, pattern completion-based retrieval of context memory

    PubMed Central

    Pevzner, Aleksandr

    2015-01-01

    No studies to date have examined whether immediate-early gene (IEG) activation is driven by context memory recall. To address this question, we utilized the context preexposure facilitation effect (CPFE) paradigm. In CPFE, animals acquire contextual fear conditioning through hippocampus-dependent rapid retrieval of a previously formed contextual representation. Despite differences in behavior, we did not find any difference in CA1 or CA3 IEG activity associated with this rapid recall phase when comparing context preexposed and non-pre-exposed groups. These findings indicate that IEG activation in CA1 and CA3 is not an accurate readout of the neural activity associated with hippocampus-dependent rapid memory retrieval. PMID:25512571

  5. Retrieval Studies with LIDORT

    NASA Technical Reports Server (NTRS)

    Bhartia, P. K. (Technical Monitor); Spurr, Robert J. D.; Chance, K. V.

    2003-01-01

    This short program of LIDORT-based research in atmospheric trace gas retrieval was conducted over the 1 year period 01 July 2002 to 30 June 2003. After consultation with the NASA reporting officer, the first of the two original proposal activities (development of a direct-fitting total O3 column retrieval algorithm with operational capability for GOME data) was replaced by other tasks. The three activities addressed were: (1) Sensitivity studies for column and profile retrieval of NO2 distributions from a new generation of multi-axis ground-based spectrometers; (2) use of the LIDORT-RRS model to determine the effect of inelastic rotational Raman scattering at SBUV wavelengths; (3) an examination of ozone profile weighting functions in the presence of optically thick tropospheric clouds.

  6. Sea Surface Salinity and Wind Retrieval Algorithm Using Combined Passive-Active L-Band Microwave Data

    NASA Technical Reports Server (NTRS)

    Yueh, Simon H.; Chaubell, Mario J.

    2011-01-01

    Aquarius is a combined passive/active L-band microwave instrument developed to map the salinity field at the surface of the ocean from space. The data will support studies of the coupling between ocean circulation, the global water cycle, and climate. The primary science objective of this mission is to monitor the seasonal and interannual variation of the large scale features of the surface salinity field in the open ocean with a spatial resolution of 150 kilometers and a retrieval accuracy of 0.2 practical salinity units globally on a monthly basis. The measurement principle is based on the response of the L-band (1.413 gigahertz) sea surface brightness temperatures (T (sub B)) to sea surface salinity. To achieve the required 0.2 practical salinity units accuracy, the impact of sea surface roughness (e.g. wind-generated ripples and waves) along with several factors on the observed brightness temperature has to be corrected to better than a few tenths of a degree Kelvin. To the end, Aquarius includes a scatterometer to help correct for this surface roughness effect.

  7. Retrieval Deficiency in Brain Activity of Working Memory in Amnesic Mild Cognitive Impairment Patients: A Brain Event-Related Potentials Study.

    PubMed

    Li, Bin-Yin; Tang, Hui-Dong; Chen, Sheng-Di

    2016-01-01

    In the early stage of Alzheimer disease (AD) or mild cognitive impairment (MCI), working memory (WM) deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in WM is impaired in MCI or early AD. We enrolled 46 subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample (DMS) task with simultaneous event-related potential (ERP) recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2, and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test) and visual spatial score of Chinese Addenbrooke's Cognitive Examination-Revised (ACE-R), while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory retrieval. The findings in the

  8. Retrieval Deficiency in Brain Activity of Working Memory in Amnesic Mild Cognitive Impairment Patients: A Brain Event-Related Potentials Study

    PubMed Central

    Li, Bin-Yin; Tang, Hui-Dong; Chen, Sheng-Di

    2016-01-01

    In the early stage of Alzheimer disease (AD) or mild cognitive impairment (MCI), working memory (WM) deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in WM is impaired in MCI or early AD. We enrolled 46 subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample (DMS) task with simultaneous event-related potential (ERP) recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2, and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test) and visual spatial score of Chinese Addenbrooke's Cognitive Examination-Revised (ACE-R), while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory retrieval. The findings in the

  9. Retrieval Attempts Enhance Learning, but Retrieval Success (versus Failure) Does Not Matter

    ERIC Educational Resources Information Center

    Kornell, Nate; Klein, Patricia Jacobs; Rawson, Katherine A.

    2015-01-01

    Retrieving information from memory enhances learning. We propose a 2-stage framework to explain the benefits of retrieval. Stage 1 takes place as one attempts to retrieve an answer, which activates knowledge related to the retrieval cue. Stage 2 begins when the answer becomes available, at which point appropriate connections are strengthened and…

  10. A description of the index of active Florida water data collection stations and a user's guide for station or site information retrieval using computer program Findex H578

    USGS Publications Warehouse

    Merritt, M.L.

    1977-01-01

    A computerized index of water-data collection activities and retrieval software to generate publication list of this information was developed for Florida. This system serves a vital need in the administration of the many and diverse water-data collection activities. Previously, needed data was very difficult to assemble for use in program planning or project implementation. Largely descriptive, the report tells how a file of computer card images has been established which contains entries for all sites in Florida at which there is currently a water-data-collection activity. Entries include information such as identification number, station name, location, type of site, county, information about data collection, funding, and other pertinent details. The computer program FINDEX selectively retrieves entries and lists them in a format suitable for publication. Updating the index is done routinely. (Woodard-USGS)

  11. Adaptive MGS Phase Retrieval

    NASA Technical Reports Server (NTRS)

    Basinger, Scott A.; Bikkannavar, Siddarayappa; Cohen, David; Green, Joseph J.; Lou, John; Ohara, Catherine; Redding, David; Shi, Fang

    2008-01-01

    Adaptive MGS Phase Retrieval software uses the Modified Gerchberg-Saxton (MGS) algorithm, an image-based sensing method that can turn any focal plane science instrument into a wavefront sensor, avoiding the need to use external metrology equipment. Knowledge of the wavefront enables intelligent control of active optical systems.

  12. Memory retrieval of smoking-related images induce greater insula activation as revealed by an fMRI based delayed matching to sample task

    PubMed Central

    Janes, AC; Ross, RS; Farmer, S; Frederick, BB; Nickerson, L; Lukas, SE; Stern, CE

    2013-01-01

    Nicotine dependence is a chronic and difficult to treat disorder. While environmental stimuli associated with smoking precipitate craving and relapse, it is unknown whether smoking cues are cognitively processed differently than neutral stimuli. To evaluate working memory differences between smoking-related and neutral stimuli, we conducted a delay-match-to-sample (DMS) task concurrently with functional magnetic resonance imaging (fMRI) in nicotine dependent participants. The DMS task evaluates brain activation during the encoding, maintenance, and retrieval phases of working memory. Smoking images induced significantly more subjective craving, and greater midline cortical activation during encoding in comparison to neutral stimuli that were similar in content yet lacked a smoking component. The insula, which is involved in maintaining nicotine dependence, was active during the successful retrieval of previously viewed smoking vs. neutral images. In contrast, neutral images required more prefrontal cortex-mediated active maintenance during the maintenance period. These findings indicate that distinct brain regions are involved in the different phases of working memory for smoking-related vs. neutral images. Importantly the results implicate the insula in the retrieval of smoking-related stimuli, which is relevant given the insula’s emerging role in addiction. PMID:24261848

  13. Activation of the dorsal hippocampal nicotinic acetylcholine receptors improves tamoxifen-induced memory retrieval impairment in adult female rats.

    PubMed

    Tajik, Azam; Rezayof, Ameneh; Ghasemzadeh, Zahra; Sardari, Maryam

    2016-07-01

    Tamoxifen (TAM), a selective estrogen receptor modulator, has frequently been used in the treatment of breast cancer. In view of the fact that cognitive deficits in women who receive adjuvant chemotherapy for breast cancer is a common health problem, using female animal models for investigating the cognitive effects of TAM administration may improve our knowledge of TAM therapy. Therefore, the present study assessed the role of dorsal hippocampal cholinergic nicotinic receptors (nAChRs) in the effect of TAM administration on memory retrieval in ovariectomized (OVX) and non-OVX female rats using a passive avoidance learning task. Our results showed that pre-test administration of TAM (2-6mg/kg) impaired memory retrieval. Pre-test intra-CA1 microinjection of nicotine (0.3-0.5μg/rat) reversed TAM-induced memory impairment. Pre-test intra-CA1 microinjection of mecamylamine (0.1-0.3μg/rat) plus 2mg/kg (an ineffective dose) of TAM impaired memory retrieval. Pre-test intra-CA1 microinjection of the same doses of nicotine and mecamylamine by themselves had no effect on memory retrieval. In OVX rats, the administration of TAM (6mg/kg) produced memory impairment but pre-test intra-CA1 microinjection of nicotine (0.5μg/rat) had no effect on TAM response. Moreover, the administration of an ineffective dose of TAM (2mg/kg) had no effect on memory retrieval in OVX rats, while pre-test intra-CA1 microinjection of mecamylamine (0.3μg/rat) impaired memory retrieval. Taken together, it can be concluded that the impairing effect of TAM on memory formation may be modulated by nAChRs of the CA1 regions. It seems that memory impairment may be considered as an important side effect of TAM. PMID:27072849

  14. Supporting users through integrated retrieval, processing, and distribution systems at the land processes distributed active archive center

    USGS Publications Warehouse

    Kalvelage, T.; Willems, Jennifer

    2003-01-01

    The design of the EOS Data and Information Systems (EOSDIS) to acquire, archive, manage and distribute Earth observation data to the broadest possible user community was discussed. A number of several integrated retrieval, processing and distribution capabilities have been explained. The value of these functions to the users were described and potential future improvements were laid out for the users. The users were interested in acquiring the retrieval, processing and archiving systems integrated so that they can get the data they want in the format and delivery mechanism of their choice.

  15. PROGRESS REPORT OF FY 2004 ACTIVITIES: IMPROVED WATER VAPOR AND CLOUD RETRIEVALS AT THE NSA/AAO

    SciTech Connect

    E. R. Westwater; V. V. Leuskiy; M. Klein; A. J. Gasiewski; and J. A. Shaw

    2004-11-01

    The basic goals of the research are to develop and test algorithms and deploy instruments that improve measurements of water vapor, cloud liquid, and cloud coverage, with a focus on the Arctic conditions of cold temperatures and low concentrations of water vapor. The importance of accurate measurements of column amounts of water vapor and cloud liquid has been well documented by scientists within the Atmospheric Radiation Measurement Program. Although several technologies have been investigated to measure these column amounts, microwave radiometers (MWR) have been used operationally by the ARM program for passive retrievals of these quantities: precipitable water vapor (PWV) and integrated water liquid (IWL). The technology of PWV and IWL retrievals has advanced steadily since the basic 2-channel MWR was first deployed at ARM CART sites Important advances are the development and refinement of the tipcal calibration method [1,2], and improvement of forward model radiative transfer algorithms [3,4]. However, the concern still remains that current instruments deployed by ARM may be inadequate to measure low amounts of PWV and IWL. In the case of water vapor, this is especially important because of the possibility of scaling and/or quality control of radiosondes by the water amount. Extremely dry conditions, with PWV less than 3 mm, commonly occur in Polar Regions during the winter months. Accurate measurements of the PWV during such dry conditions are needed to improve our understanding of the regional radiation energy budgets. The results of a 1999 experiment conducted at the ARM North Slope of Alaska/Adjacent Arctic Ocean (NSA/AAO) site during March of 1999 [5] have shown that the strength associated with the 183 GHz water vapor absorption line makes radiometry in this frequency regime suitable for measuring low amounts of PWV. As a portion of our research, we conducted another millimeter wave radiometric experiment at the NSA/AAO in March-April 2004. This

  16. Activation of the Transcription Factor NF-[Kappa]B by Retrieval Is Required for Long-Term Memory Reconsolidation

    ERIC Educational Resources Information Center

    Maldonado, Hector; Romano, Arturo; Merlo, Emiliano; Freudenthal, Ramiro

    2005-01-01

    Several studies support that stored memories undergo a new period of consolidation after retrieval. It is not known whether this process, termed reconsolidation, requires the same transcriptional mechanisms involved in consolidation. Increasing evidence supports the participation of the transcription factor NF-[Kappa]B in memory. This was…

  17. Event-Related fMRI Studies of Episodic Encoding and Retrieval: Meta-Analyses Using Activation Likelihood Estimation

    ERIC Educational Resources Information Center

    Spaniol, Julia; Davidson, Patrick S. R.; Kim, Alice S. N.; Han, Hua; Moscovitch, Morris; Grady, Cheryl L.

    2009-01-01

    The recent surge in event-related fMRI studies of episodic memory has generated a wealth of information about the neural correlates of encoding and retrieval processes. However, interpretation of individual studies is hampered by methodological differences, and by the fact that sample sizes are typically small. We submitted results from studies of…

  18. Identifying the Influence of Variable Ice Types on Passive and Active Microwave Measurements for the Purpose of SWE Retrieval

    NASA Astrophysics Data System (ADS)

    Gunn, G. E.; Duguay, C. R.; Derksen, C.

    2010-12-01

    ) over freshwater ice (Sitidgi Lake) with the highest R coefficient noticed in the H pol for 6.9 and 19 GHz emissions (R = 0.84 and 0.58 respectively). In brackish water, 6.9 and 19 GHz PM Tbs exhibited a negative relationship as a result of a high concentration of bubbles at the ice/water interface, and the incorporation of lossy brine pockets into the ice medium. This study identifies congruency between passive and active microwave measurements over lake ice for the purpose of improving SWE retrieval algorithms. Further quantification of passive microwave emission is needed for unique ice types, however it has been established that cross-polarised X-band backscatter can be utilized as a priori information for spaceborne PM algorithms, providing information on ice type, characteristics (floating, frozen to bed), and the presence of bubbles at the ice/water interface.

  19. Comparison of Superb Micro-Vascular Ultrasound Imaging (SMI) and Contrast-Enhanced Ultrasound (CEUS) for Detection of Endoleaks After Endovascular Aneurysm Repair (EVAR)

    PubMed Central

    Gabriel, Marcin; Tomczak, Jolanta; Snoch-Ziółkiewicz, Magdalena; Dzieciuchowicz, Łukasz; Strauss, Ewa; Oszkinis, Grzegorz

    2016-01-01

    Patient: Male, 68 Final Diagnosis: Unusual clinical course Symptoms: None Medication: — Clinical Procedure: Angio CT Specialty: Surgery Objective: Challenging differential diagnosis Background: High-resolution contrast-enhanced ultrasound is one of methods used in the detection and characterization of endoleaks, which is a frequent complication after EVAR. A new technology provided by Toshiba’s AplioTM 500 ultrasound system, called Superb Micro-Vascular Imaging (SMI), is dedicated specifically to imaging very low flow states and appears to be a promising new method for detection of endoleaks. Case Report: After endovascular treatment, a 68-year-old patient who had stent-graft implantation underwent clinical examinations, including contrast-enhanced ultrasound (CEUS), superb micro-vascular imaging (SMI), and computed tomographic angiography (CTA), revealing additional information about abnormal blood flow localized in the periphery of the sack of the left common iliac artery aneurysm. By using CEUS and SMI, the endoleak was clearly visible. Conclusions: This case report illustrates the potential clinical value of this advanced Doppler technology (SMI) and how it could influence clinical management. PMID:26806053

  20. Embolization by Direct Puncture with a Transpedicular Approach Using an Isocenter Puncture (ISOP) Method in a Patient with a Type II Endoleak After Endovascular Aortic Repair (EVAR)

    SciTech Connect

    Ogawa, Yukihisa Hamaguchi, Shingo; Nishimaki, Hiroshi; Kon, Yuri; Chiba, Kiyoshi; Sakurai, Yuka; Murakami, Kenji; Arai, Yasunori; Miyairi, Takeshi; Nakajima, Yasuo

    2015-06-15

    BackgroundEndovascular aortic repair (EVAR) requires further intervention in 20-30 % of cases, often due to type II endoleak (T2EL). Management options for T2EL include transarterial embolization, direct puncture (DP), or transcaval embolization. We report the case of an 80-year-old man with T2EL who successfully underwent DP embolization.MethodsEmbolization by DP was performed with a transpedicular approach using an isocenter puncture (ISOP) method. An isocenter marker (ICM) was placed at a site corresponding to the aneurysm sac on fluoroscopy in two directions (frontal and lateral views). A vertebroplasty needle was inserted tangentially to the ICM under fluoroscopy and advanced to the anterior wall of the vertebral body. A 20 cm-length, 20-G-PTCD needle was inserted through the outer needle of the 13-G needle and advanced to the ICM. Sac embolization using 25 % N-buty-2-cyanoacrylate diluted with Lipiodol was performed. After complete embolization, rotational DA confirmed good filling of the sac with Lipiodol. The outer cannula and 13-G needle were removed and the procedure was completed.ResultsThe patient was discharged the next day. Contrast-enhanced computed tomography 1 and 8 months later showed no Lipiodol washout in the aneurysm sac, no endoleak recurrence, and no expansion of the excluded aneurysm.ConclusionDP with a transpedicular approach using ISOP may be useful when translumbar and transabdominal approaches prove difficult.

  1. PALS (Passive Active L-band System) Radiometer-Based Soil Moisture Retrieval for the SMAP Validation Experiment 2012 (SMAPVEX12)

    NASA Astrophysics Data System (ADS)

    Colliander, A.; Jackson, T. J.; Chan, S.; Bindlish, R.; O'Neill, P. E.; Chazanoff, S. L.; McNairn, H.; Bullock, P.; Powers, J.; Wiseman, G.; Berg, A. A.; Magagi, R.; Njoku, E. G.

    2014-12-01

    NASA's (National Aeronautics and Space Administration) Soil Moisture Active Passive (SMAP) mission is scheduled for launch in early January 2015. For pre-launch soil moisture algorithm development and validation, the SMAP project and NASA coordinated a SMAP Validation Experiment 2012 (SMAPVEX12) together with Agriculture and Agri-Food Canada in the vicinity of Winnipeg, Canada in June 7-July 19, 2012. Coincident active and passive airborne L-band data were acquired using the Passive Active L-band System (PALS) on 17 days during the experiment. Simultaneously with the PALS measurements, soil moisture ground truth data were collected manually. The vegetation and surface roughness were sampled on non-flight days. The SMAP mission will produce surface (top 5 cm) soil moisture products a) using a combination of its L-band radiometer and SAR (Synthetic Aperture Radar) measurements, b) using the radiometer measurement only, and c) using the SAR measurements only. The SMAPVEX12 data are being utilized for the development and testing of the algorithms applied for generating these soil moisture products. This talk will focus on presenting results of retrieving surface soil moisture using the PALS radiometer. The issues that this retrieval faces are very similar to those faced by the global algorithm using the SMAP radiometer. However, the different spatial resolution of the two observations has to be accounted for in the analysis. The PALS 3 dB footprint in the experiment was on the order of 1 km, whereas the SMAP radiometer has a footprint of about 40 km. In this talk forward modeled brightness temperature over the manually sampled fields and the retrieved soil moisture over the entire experiment domain are presented and discussed. In order to provide a retrieval product similar to that of the SMAP passive algorithm, various ancillary information had to be obtained for the SMAPVEX12 domain. In many cases there are multiple options on how to choose and reprocess these data

  2. Using Airborne High Spectral Resolution Lidar Data to Evaluate Combined Active Plus Passive Retrievals of Aerosol Extinction Profiles

    NASA Technical Reports Server (NTRS)

    Burton, S. P.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. W.; Kittaka, C.; Vaughn, M. A.; Remer, L. A.

    2010-01-01

    We derive aerosol extinction profiles from airborne and space-based lidar backscatter signals by constraining the retrieval with column aerosol optical thickness (AOT), with no need to rely on assumptions about aerosol type or lidar ratio. The backscatter data were acquired by the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL) and by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite. The HSRL also simultaneously measures aerosol extinction coefficients independently using the high spectral resolution lidar technique, thereby providing an ideal data set for evaluating the retrieval. We retrieve aerosol extinction profiles from both HSRL and CALIOP attenuated backscatter data constrained with HSRL, Moderate-Resolution Imaging Spectroradiometer (MODIS), and Multiangle Imaging Spectroradiometer column AOT. The resulting profiles are compared with the aerosol extinction measured by HSRL. Retrievals are limited to cases where the column aerosol thickness is greater than 0.2 over land and 0.15 over water. In the case of large AOT, the results using the Aqua MODIS constraint over water are poorer than Aqua MODIS over land or Terra MODIS. The poorer results relate to an apparent bias in Aqua MODIS AOT over water observed in August 2007. This apparent bias is still under investigation. Finally, aerosol extinction coefficients are derived from CALIPSO backscatter data using AOT from Aqua MODIS for 28 profiles over land and 9 over water. They agree with coincident measurements by the airborne HSRL to within +/-0.016/km +/- 20% for at least two-thirds of land points and within +/-0.028/km +/- 20% for at least two-thirds of ocean points.

  3. Influence of gravity compensation on kinematics and muscle activation patterns during reach and retrieval in subjects with cervical spinal cord injury: an explorative study.

    PubMed

    Kloosterman, Marieke G M; Snoek, Govert J; Kouwenhoven, Mirjam; Nene, Anand V; Jannink, Michiel J A

    2010-01-01

    Many interventions in upper-limb rehabilitation after cervical spinal cord injury (CSCI) use arm support (gravity compensation); however, its specific effects on kinematics and muscle activation characteristics in subjects with a CSCI are largely unknown. We conducted a cross-sectional explorative study to study these effects. Nine subjects with a CSCI performed two goal-directed arm movements (maximal reach, reach and retrieval) with and without gravity compensation. Angles at elbow and shoulder joints and muscle activation were measured and compared. Seven subjects reduced elbow extension (range 1.8°-4.5°) during the maximal reaching task with gravity compensation. In the reach and retrieval task with gravity compensation, all subjects decreased elbow extension (range 0.1°-11.0°). Eight subjects executed movement closer to the body. Regarding muscle activation, gravity compensation did not influence timing; however, the amplitude of activation decreased, especially in antigravity muscles, namely mean change +/- standard deviation of descending part of trapezius (18.2% +/- 37.5%), anterior part of deltoid (37.7% +/- 16.7%), posterior part of deltoid (32.0% +/- 13.9%), and long head biceps (49.6% +/- 20.0%). Clinical implications for the use of gravity compensation in rehabilitation (during activities of daily living or exercise therapy) should be further investigated with a larger population. PMID:21110258

  4. Revised description of index of Florida water data collection active stations and a user's guide for station or site information retrieval computer program FINDEX H578

    USGS Publications Warehouse

    Geiger, Linda H.

    1983-01-01

    The report is an update of U.S. Geological Survey Open-File Report 77-703, which described a retrieval program for administrative index of active data-collection sites in Florida. Extensive changes to the Findex system have been made since 1977 , making the previous report obsolete. A description of the data base and computer programs that are available in the Findex system are documented in this report. This system serves a vital need in the administration of the many and diverse water-data collection activities. District offices with extensive data-collection activities will benefit from the documentation of the system. Largely descriptive, the report tells how a file of computer card images has been established which contains entries for all sites in Florida at which there is currently a water-data collection activity. Entries include information such as identification number, station name, location, type of site, county, frequency of data collection, funding, and other pertinent details. The computer program FINDEX selectively retrieves entries and lists them in a format suitable for publication. The index is updated routinely. (USGS)

  5. Skill in Retrievals

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Manning, Evan

    2008-01-01

    Retrieval Skill quantifies the ability of one retrieval from a sounder to be more accurate than the best forecast relative to another with the same of another sounder. This is summarized using a Retrieval Anomaly Skill Score (RASS) which is the cor (retrieved-background, truth-background) * sqrt(f), Where f is defined as the ratio of accepted to the possible retrievals. Charts show various features and comparisons of RASS to other methods of retrieval.

  6. Autonomous Phase Retrieval Calibration

    NASA Technical Reports Server (NTRS)

    Estlin, Tara A.; Chien, Steve A.; Castano, Rebecca; Gaines, Daniel M.; Doubleday, Joshua R.; Schoolcraft, Josua B.; Oyake, Amalaye; Vaughs, Ashton G.; Torgerson, Jordan L.

    2011-01-01

    The Palomar Adaptive Optics System actively corrects for changing aberrations in light due to atmospheric turbulence. However, the underlying internal static error is unknown and uncorrected by this process. The dedicated wavefront sensor device necessarily lies along a different path than the science camera, and, therefore, doesn't measure the true errors along the path leading to the final detected imagery. This is a standard problem in adaptive optics (AO) called "non-common path error." The Autonomous Phase Retrieval Calibration (APRC) software suite performs automated sensing and correction iterations to calibrate the Palomar AO system to levels that were previously unreachable.

  7. Innovative grout/retrieval demonstration final report

    SciTech Connect

    Loomis, G.G.; Thompson, D.N.

    1995-01-01

    This report presents the results of an evaluation of an innovative retrieval technique for buried transuranic waste. Application of this retrieval technique was originally designed for full pit retrieval; however, it applies equally to a hot spot retrieval technology. The technique involves grouting the buried soil waste matrix with a jet grouting procedure, applying an expansive demolition grout to the matrix, and retrieving the debris. The grouted matrix provides an agglomeration of fine soil particles and contaminants resulting in an inherent contamination control during the dusty retrieval process. A full-scale field demonstration of this retrieval technique was performed on a simulated waste pit at the Idaho National Engineering Laboratory. Details are reported on all phases of this proof-of-concept demonstration including pit construction, jet grouting activities, application of the demolition grout, and actual retrieval of the grouted pit. A quantitative evaluation of aerosolized soils and rare earth tracer spread is given for all phases of the demonstration, and these results are compared to a baseline retrieval activity using conventional retrieval means. 8 refs., 47 figs., 10 tabs.

  8. Temporal structure in associative retrieval

    PubMed Central

    Kurth-Nelson, Zeb; Barnes, Gareth; Sejdinovic, Dino; Dolan, Ray; Dayan, Peter

    2015-01-01

    Electrophysiological data disclose rich dynamics in patterns of neural activity evoked by sensory objects. Retrieving objects from memory reinstates components of this activity. In humans, the temporal structure of this retrieved activity remains largely unexplored, and here we address this gap using the spatiotemporal precision of magnetoencephalography (MEG). In a sensory preconditioning paradigm, 'indirect' objects were paired with 'direct' objects to form associative links, and the latter were then paired with rewards. Using multivariate analysis methods we examined the short-time evolution of neural representations of indirect objects retrieved during reward-learning about direct objects. We found two components of the evoked representation of the indirect stimulus, 200 ms apart. The strength of retrieval of one, but not the other, representational component correlated with generalization of reward learning from direct to indirect stimuli. We suggest the temporal structure within retrieved neural representations may be key to their function. DOI: http://dx.doi.org/10.7554/eLife.04919.001 PMID:25615722

  9. Analyzing Document Retrievability in Patent Retrieval Settings

    NASA Astrophysics Data System (ADS)

    Bashir, Shariq; Rauber, Andreas

    Most information retrieval settings, such as web search, are typically precision-oriented, i.e. they focus on retrieving a small number of highly relevant documents. However, in specific domains, such as patent retrieval or law, recall becomes more relevant than precision: in these cases the goal is to find all relevant documents, requiring algorithms to be tuned more towards recall at the cost of precision. This raises important questions with respect to retrievability and search engine bias: depending on how the similarity between a query and documents is measured, certain documents may be more or less retrievable in certain systems, up to some documents not being retrievable at all within common threshold settings. Biases may be oriented towards popularity of documents (increasing weight of references), towards length of documents, favour the use of rare or common words; rely on structural information such as metadata or headings, etc. Existing accessibility measurement techniques are limited as they measure retrievability with respect to all possible queries. In this paper, we improve accessibility measurement by considering sets of relevant and irrelevant queries for each document. This simulates how recall oriented users create their queries when searching for relevant information. We evaluate retrievability scores using a corpus of patents from US Patent and Trademark Office.

  10. EVA Retriever Demonstration

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The EVA retriever is demonstrated in the Manipulator Development Facility (MDF). The retriever moves on the air bearing table 'searching' for its target, in this case tools 'dropped' by astronauts on orbit.

  11. Retrieval during Learning Facilitates Subsequent Memory Encoding

    ERIC Educational Resources Information Center

    Pastotter, Bernhard; Schicker, Sabine; Niedernhuber, Julia; Bauml, Karl-Heinz T.

    2011-01-01

    In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied 5…

  12. Ground Validated Freeze/Thaw Timings Using Multifrequency Active and Passive Satellite Observations: A Comparison of Retrieval Methodologies

    NASA Astrophysics Data System (ADS)

    Steiner, N.; McDonald, K. C.; Schroeder, R.; Azarderakhsh, M.

    2012-12-01

    The freeze/thaw state of the Earth's land surface has a considerable influence on the terrestrial water, energy and carbon cycles. Microwave frequency satellite observations are often used to the determine the landcover freeze/thaw state because of a high temporal repeat time and global coverage. Methodologies have been developed to detect changes in active and passive microwave-frequency measurements that occur during the transition from the frozen to thawed state. We evaluate the performance of several of these methodologies including: absolute-value thresholding, convolution-based change detection and running window methods. This validation effort is part of the preparations for the global freeze/thaw product derived from the Soil Moisture Active Passive (SMAP) mission. Freeze/thaw records produced from each method and sensor are evaluated for the period, 2000-2012, at locations containing detailed in-situ observations from ground station networks. Additionally, at several sites we illustrate in detail the microwave response during freeze/thaw transitions for all frequencies and polarizations using in-situ measurements of snow depth, soil temperature and vegetative indices. Channels and polarizations for each sensor are evaluated independently in order to illustrate useful approaches and combinations for future data fusion projects or combined active and passive freeze/thaw algorithms. Passive microwave observations used in this study are from the Special Sensor Microwave Imager (SSM/I) including the 19, 22 37 and 88 GHz channels, and span the entire measurement period. The active microwave components are temporally staggered and include the 13.4 GHz QuikSCAT scatterometer aboard SeaWinds from 1999-2009 and the Advanced Scatterometer (ASCAT) at 5.255 GHz onboard the European Organization for the Exploitation of Meteorological Satellite from 2009 onward. More focused attention will be given to the period of scatterometer overlap. For a consistent scatterometer

  13. Retrieval of the photochemical reflectance index for assessing xanthophyll cycle activity: a comparison of near-surface optical sensors

    NASA Astrophysics Data System (ADS)

    Harris, A.; Gamon, J. A.; Pastorello, G. Z.; Wong, C. Y. S.

    2014-11-01

    Unattended optical sensors are increasingly being deployed on eddy covariance flux towers and are often used to complement existing vegetation and micrometeorological measurements to enable assessment of biophysical states and biogeochemical processes over a range of spatial scales. Of particular interest are sensors that can measure the photochemical reflectance index (PRI), which can provide information pertaining to leaf pigments and photosynthetic activity. This interest has facilitated the production of a new range of lower-cost multispectral sensors specifically designed to measure temporal changes in the PRI signal. However, little is known about the characteristics (spectral, radiometric and temporal) of many of these PRI sensors, making it difficult to compare data obtained from these sensors across time, geographical locations and instruments. Furthermore, direct testing of the capability of these sensors to actually detect the conversion of the xanthophyll cycle, which is the original biological basis of the PRI diurnal signal, is largely absent, often resulting in an unclear interpretation of the signal, particularly given the wide range of factors now known to influence PRI. Through a series of experiments, we assess the sensitivity of one of the leading brands of PRI sensor (Skye SKR 1800) to changes in vegetation photosynthetic activity in response to changing irradiance. We compare the results with those obtained using a more expensive industry-standard visible to near-infrared hyperspectral spectrometer (PP Systems UniSpec) and determine the radiometric compatibility of measurements made by the different instruments. Results suggest that the SKR 1800 instrument is able to track rapid (seconds to minutes) and more gradual diurnal changes in photosynthetic activity associated with xanthophyll cycle pigment conversion. Measurements obtained from both the high and lower cost instrument were significantly linearly correlated but were subject to a large

  14. Differential Left Hippocampal Activation during Retrieval with Different Types of Reminders: An fMRI Study of the Reconsolidation Process

    PubMed Central

    De Pino, Gabriela; Fernández, Rodrigo Sebastián; Villarreal, Mirta Fabiana; Pedreira, María Eugenia

    2016-01-01

    Consolidated memories return to a labile state after the presentation of cues (reminders) associated with acquisition, followed by a period of stabilization (reconsolidation). However not all cues are equally effective in initiating the process, unpredictable cues triggered it, predictable cues do not. We hypothesize that the different effects observed by the different reminder types on memory labilization-reconsolidation depend on a differential neural involvement during reminder presentation. To test it, we developed a declarative task and compared the efficacy of three reminder types in triggering the process in humans (Experiment 1). Finally, we compared the brain activation patterns between the different conditions using functional magnetic resonance imaging (fMRI) (Experiment 2). We confirmed that the unpredictable reminder is the most effective in initiating the labilization-reconsolidation process. Furthermore, only under this condition there was differential left hippocampal activation during its presentation. We suggest that the left hippocampus is detecting the incongruence between actual and past events and allows the memory to be updated. PMID:26991776

  15. Differential Left Hippocampal Activation during Retrieval with Different Types of Reminders: An fMRI Study of the Reconsolidation Process.

    PubMed

    Forcato, Cecilia; Bavassi, Luz; De Pino, Gabriela; Fernández, Rodrigo Sebastián; Villarreal, Mirta Fabiana; Pedreira, María Eugenia

    2016-01-01

    Consolidated memories return to a labile state after the presentation of cues (reminders) associated with acquisition, followed by a period of stabilization (reconsolidation). However not all cues are equally effective in initiating the process, unpredictable cues triggered it, predictable cues do not. We hypothesize that the different effects observed by the different reminder types on memory labilization-reconsolidation depend on a differential neural involvement during reminder presentation. To test it, we developed a declarative task and compared the efficacy of three reminder types in triggering the process in humans (Experiment 1). Finally, we compared the brain activation patterns between the different conditions using functional magnetic resonance imaging (fMRI) (Experiment 2). We confirmed that the unpredictable reminder is the most effective in initiating the labilization-reconsolidation process. Furthermore, only under this condition there was differential left hippocampal activation during its presentation. We suggest that the left hippocampus is detecting the incongruence between actual and past events and allows the memory to be updated. PMID:26991776

  16. Combining energy and Laplacian regularization to accurately retrieve the depth of brain activity of diffuse optical tomographic data

    NASA Astrophysics Data System (ADS)

    Chiarelli, Antonio M.; Maclin, Edward L.; Low, Kathy A.; Mathewson, Kyle E.; Fabiani, Monica; Gratton, Gabriele

    2016-03-01

    Diffuse optical tomography (DOT) provides data about brain function using surface recordings. Despite recent advancements, an unbiased method for estimating the depth of absorption changes and for providing an accurate three-dimensional (3-D) reconstruction remains elusive. DOT involves solving an ill-posed inverse problem, requiring additional criteria for finding unique solutions. The most commonly used criterion is energy minimization (energy constraint). However, as measurements are taken from only one side of the medium (the scalp) and sensitivity is greater at shallow depths, the energy constraint leads to solutions that tend to be small and superficial. To correct for this bias, we combine the energy constraint with another criterion, minimization of spatial derivatives (Laplacian constraint, also used in low resolution electromagnetic tomography, LORETA). Used in isolation, the Laplacian constraint leads to solutions that tend to be large and deep. Using simulated, phantom, and actual brain activation data, we show that combining these two criteria results in accurate (error <2 mm) absorption depth estimates, while maintaining a two-point spatial resolution of <24 mm up to a depth of 30 mm. This indicates that accurate 3-D reconstruction of brain activity up to 30 mm from the scalp can be obtained with DOT.

  17. Multilingual information retrieval system

    NASA Astrophysics Data System (ADS)

    Zhou, Hong; Chan, Syin; Lai, Kok-Fung

    1996-11-01

    In this paper, we present an approach in implementing intelligent information retrieval systems. We have constructed a multilingual information system which combines both image and text retrieval. We have developed an English/Chinese text retrieval tool on the WWW, and later incorporated an image retrieval tool based on associated multilingual captions. The system allows the general public to locate and keep abreast of information about Singapore. It has a novel user interface which accepts queries that are expressed in English, Chinese and mixed text into its database. The titles, summaries, URLs and the matching scores of retrieved documents will then be returned, and a thumbnail will be displayed as well if an image document is retrieved.

  18. Microbial biomass, activity, and community structure of water and particulates retrieved by backflow from a waterflood injection well.

    PubMed

    McKinley, V L; Costerton, J W; White, D C

    1988-06-01

    Oil field injection water was allowed to back flow from two wells at the Packard drill site in Los Angeles, Calif., and was sampled at various times to obtain information about the biomass, potential activity, and community structure of the microbiota in the reservoir formation and in the injection water. Biomass was greatest in water samples that came from the zone near the injection site and dropped off sharply in subsequent samples, which were assumed to come from zones farther away from the well. Samples obtained from near the well also had visible exopolysaccharide blankets, as seen in scanning electron microscopic preparations. In one of the wells that was sampled, rates of glucose or acetate incorporation into microbial lipids correlated with biomass; but in the other well, activities correlated with the sampling time (volume of water that back flowed). Transmission electron micrographs showed a diverse, gram-negative bacterial population in a variety of physiological states. The analysis of the phospholipid ester-linked fatty acid profiles of the samples revealed consistently large proportions of 18:1omega7c fatty acids, indicating the presence of many anaerobes, facultative organisms, or both. Proportions of cyclopropyl fatty acids and ratios of trans/cis monoenoic compounds increased with the volume of water that back flowed (analogous with the distance into the formation), while the ratio of unsaturated/saturated compounds decreased, possibly indicating higher levels of stress or starvation in the microbial communities farthest from the injection well. Greater than 90% of the total biomass was trapped on glass fiber filters, indicating that the microbiota were largely attached to particles or were clumped. These sampling techniques and analytical methods may prove useful in monitoring for problems with microbes (e.g., plugging) in waterflood operations and in the preparation of water injection wells for enhanced oil recovery by the use of microbes. PMID

  19. Microbial Biomass, Activity, and Community Structure of Water and Particulates Retrieved by Backflow from a Waterflood Injection Well

    PubMed Central

    McKinley, Vicky L.; Costerton, J. William; White, David C.

    1988-01-01

    Oil field injection water was allowed to back flow from two wells at the Packard drill site in Los Angeles, Calif., and was sampled at various times to obtain information about the biomass, potential activity, and community structure of the microbiota in the reservoir formation and in the injection water. Biomass was greatest in water samples that came from the zone near the injection site and dropped off sharply in subsequent samples, which were assumed to come from zones farther away from the well. Samples obtained from near the well also had visible exopolysaccharide blankets, as seen in scanning electron microscopic preparations. In one of the wells that was sampled, rates of glucose or acetate incorporation into microbial lipids correlated with biomass; but in the other well, activities correlated with the sampling time (volume of water that back flowed). Transmission electron micrographs showed a diverse, gram-negative bacterial population in a variety of physiological states. The analysis of the phospholipid ester-linked fatty acid profiles of the samples revealed consistently large proportions of 18:1ω7c fatty acids, indicating the presence of many anaerobes, facultative organisms, or both. Proportions of cyclopropyl fatty acids and ratios of trans/cis monoenoic compounds increased with the volume of water that back flowed (analogous with the distance into the formation), while the ratio of unsaturated/saturated compounds decreased, possibly indicating higher levels of stress or starvation in the microbial communities farthest from the injection well. Greater than 90% of the total biomass was trapped on glass fiber filters, indicating that the microbiota were largely attached to particles or were clumped. These sampling techniques and analytical methods may prove useful in monitoring for problems with microbes (e.g., plugging) in waterflood operations and in the preparation of water injection wells for enhanced oil recovery by the use of microbes. Images

  20. Technical requirements specification for tank waste retrieval

    SciTech Connect

    Lamberd, D.L.

    1996-09-26

    This document provides the technical requirements specification for the retrieval of waste from the underground storage tanks at the Hanford Site. All activities covered by this scope are conducted in support of the Tank Waste Remediation System (TWRS) mission.

  1. AN ACTIVE-PASSIVE COMBINED ALGORITHM FOR HIGH SPATIAL RESOLUTION RETRIEVAL OF SOIL MOISTURE FROM SATELLITE SENSORS (Invited)

    NASA Astrophysics Data System (ADS)

    Lakshmi, V.; Mladenova, I. E.; Narayan, U.

    2009-12-01

    Soil moisture is known to be an essential factor in controlling the partitioning of rainfall into surface runoff and infiltration and solar energy into latent and sensible heat fluxes. Remote sensing has long proven its capability to obtain soil moisture in near real-time. However, at the present time we have the Advanced Scanning Microwave Radiometer (AMSR-E) on board NASA’s AQUA platform is the only satellite sensor that supplies a soil moisture product. AMSR-E coarse spatial resolution (~ 50 km at 6.9 GHz) strongly limits its applicability for small scale studies. A very promising technique for spatial disaggregation by combining radar and radiometer observations has been demonstrated by the authors using a methodology is based on the assumption that any change in measured brightness temperature and backscatter from one to the next time step is due primarily to change in soil wetness. The approach uses radiometric estimates of soil moisture at a lower resolution to compute the sensitivity of radar to soil moisture at the lower resolution. This estimate of sensitivity is then disaggregated using vegetation water content, vegetation type and soil texture information, which are the variables on which determine the radar sensitivity to soil moisture and are generally available at a scale of radar observation. This change detection algorithm is applied to several locations. We have used aircraft observed active and passive data over Walnut Creek watershed in Central Iowa in 2002; the Little Washita Watershed in Oklahoma in 2003 and the Murrumbidgee Catchment in southeastern Australia for 2006. All of these locations have different soils and land cover conditions which leads to a rigorous test of the disaggregation algorithm. Furthermore, we compare the derived high spatial resolution soil moisture to in-situ sampling and ground observation networks

  2. Information Retrieval System.

    ERIC Educational Resources Information Center

    Mahle, Jack D., Jr.

    The Fort Detrick Information Retrieval System is a system of computer programs written in COBOL for a CDC 3150 to store and retrieve information about the scientific and technical reports and documents of the Fort Detrick Technical Library. The documents and reports have been abstracted and indexed. This abstract, the subject matter descriptors,…

  3. RETRIEVAL EVENTS EVALUATION

    SciTech Connect

    T. Wilson

    1999-11-12

    The purpose of this analysis is to evaluate impacts to the retrieval concept presented in the Design Analysis ''Retrieval Equipment and Strategy'' (Reference 6), from abnormal events based on Design Basis Events (DBE) and Beyond Design Basis Events (BDBE) as defined in two recent analyses: (1) DBE/Scenario Analysis for Preclosure Repository Subsurface Facilities (Reference 4); and (2) Preliminary Preclosure Design Basis Event Calculations for the Monitored Geologic Repository (Reference 5) The objective of this task is to determine what impacts the DBEs and BDBEs have on the equipment developed for retrieval. The analysis lists potential impacts and recommends changes to be analyzed in subsequent design analyses for developed equipment, or recommend where additional equipment may be needed, to allow retrieval to be performed in all DBE or BDBE situations. This analysis supports License Application design and therefore complies with the requirements of Systems Description Document input criteria comparison as presented in Section 7, Conclusions. In addition, the analysis discusses the impacts associated with not using concrete inverts in the emplacement drifts. The ''Retrieval Equipment and Strategy'' analysis was based on a concrete invert configuration in the emplacement drift. The scope of the analysis, as presented in ''Development Plan for Retrieval Events Evaluation'' (Reference 3) includes evaluation and criteria of the following: Impacts to retrieval from the emplacement drift based on DBE/BDBEs, and changes to the invert configuration for the preclosure period. Impacts to retrieval from the main drifts based on DBE/BDBEs for the preclosure period.

  4. Knowledge Retrieval Solutions.

    ERIC Educational Resources Information Center

    Khan, Kamran

    1998-01-01

    Excalibur RetrievalWare offers true knowledge retrieval solutions. Its fundamental technologies, Adaptive Pattern Recognition Processing and Semantic Networks, have capabilities for knowledge discovery and knowledge management of full-text, structured and visual information. The software delivers a combination of accuracy, extensibility,…

  5. Efficient Graffiti Image Retrieval

    SciTech Connect

    Yang, Chunlei; Wong, Pak C.; Ribarsky, William; Fan, Jianping

    2012-07-05

    Research of graffiti character recognition and retrieval, as a branch of traditional optical character recognition (OCR), has started to gain attention in recent years. We have investigated the special challenge of the graffiti image retrieval problem and propose a series of novel techniques to overcome the challenges. The proposed bounding box framework locates the character components in the graffiti images to construct meaningful character strings and conduct image-wise and semantic-wise retrieval on the strings rather than the entire image. Using real world data provided by the law enforcement community to the Pacific Northwest National Laboratory, we show that the proposed framework outperforms the traditional image retrieval framework with better retrieval results and improved computational efficiency.

  6. Dissociating the "retrieval success" regions of the brain: effects of retrieval delay.

    PubMed

    Huijbers, W; Pennartz, C M A; Daselaar, S M

    2010-01-01

    There is abundant evidence that the hippocampal formation critically supports episodic memory retrieval, the remembering of episodes including contextual details. Yet, a group of other brain regions has also been consistently implicated in successful episodic retrieval. This retrieval success network (RSN) includes the posterior midline region, medial prefrontal cortex (mPFC), and posterior parietal cortex (PPC). Despite these consistent findings, the functional roles of the RSN regions remain poorly understood. Given that vivid remembering leads to high-confidence retrieval decisions, it is unclear whether activity in these regions reflects episodic long-term memory, or is merely associated with retrieval confidence. In order to distinguish between these alternatives, we manipulated study-test delays within the context of a continuous recognition task during fMRI-scanning. The design was based on previous evidence indicating that retrieval at short delays is easier leading to high-evidence mnemonic decisions, whereas retrieval at longer delays is more difficult but also more hippocampus-dependent. Confirming previous findings, we found that retrieval decisions at short delays were more accurate and faster, and that the hippocampus showed greater activity at longer delays. Within the other RSN regions, we found three distinct activation patterns as a function of delay. Similar to the hippocampus, the retrosplenial cortex showed increased activity as a function of retrieval delay. Dorsal PPC and the precuneus showed decreased activity. Finally, the posterior cingulate, medial PFC and ventral PPC showed a V-shaped pattern. These findings support the idea that dorsal PPC and the precuneus are involved in decision-related retrieval processes rather than successful remembering. PMID:19835893

  7. Topological Aspects of Information Retrieval.

    ERIC Educational Resources Information Center

    Egghe, Leo; Rousseau, Ronald

    1998-01-01

    Discusses topological aspects of theoretical information retrieval, including retrieval topology; similarity topology; pseudo-metric topology; document spaces as topological spaces; Boolean information retrieval as a subsystem of any topological system; and proofs of theorems. (LRW)

  8. Solid waste retrieval. Phase 1, Operational basis

    SciTech Connect

    Johnson, D.M.

    1994-09-30

    This Document describes the operational requirements, procedures, and options for execution of the retrieval of the waste containers placed in buried storage in Burial Ground 218W-4C, Trench 04 as TRU waste or suspect TRU waste under the activity levels defining this waste in effect at the time of placement. Trench 04 in Burial Ground 218W-4C is totally dedicated to storage of retrievable TRU waste containers or retrievable suspect TRU waste containers and has not been used for any other purpose.

  9. Error characterization of retrievals for active remote Sensing instruments in the ARM climate research facility at the Southern Great Plains site

    NASA Astrophysics Data System (ADS)

    Chandrasekar, C. V.; Hardin, J. C.; Jensen, M. P.

    2012-12-01

    The ARM Climate Research Facility deploys a network of highly instrumented ground stations, including both mobile and aerial facilities to support the study of global climate change by the national and international research community. The Southern Great Plains facility (SGP) hosts a network of C, X, and K band radars; some are in scanning mode and some are in vertically pointing mode. As an example, the Mid-Latitude Continental Convective Clouds Experiment (MC3E) (Jensen, et al. 2011), was a joint DOE Atmospheric Radiation Measurement (ARM) and NASA Global Precipitation Measurements (GPM) field campaign which took place from April - June 2011 in Central Oklahoma centered at the ARM SGP site. This paper presents retrieval methodologies for the ARM instrument suite with a focus on the error characterization for the radar measurements and the retrievals. There is extensive literature on retrieval algorithms for precipitation and cloud parameters from single frequency, dual-polarization radar systems. Multiple radar deployments are becoming more common, and the MC3E is a text book example of such a deployment. Additionally, networked deployments are becoming more common (Chandrasekar, et al. 2010), resulting in networked retrievals, initially used for attenuation mitigation. Since then, networked retrievals have expanded to include DSDs from networked X-band or Ku-band radars (Yoshikawa, et al., 2012). The above retrieval methodologies were for homogeneous, single frequency systems; the multi frequency nature of the deployment during the MC3E program is the motivation for the integrated formulation and error characterization presented in this paper. The set of radars consists of the NASA NPOL radar at S-band, as well as the C and X-band radars from the ARM program, namely the C-SAPR and X-SAPR family. This paper presents a comprehensive integrated retrieval methodology focusing on error characterization to obtain microphysical retrieval including drop size

  10. Single-shell tank retrieval program mission analysis report

    SciTech Connect

    Stokes, W.J.

    1998-08-11

    This Mission Analysis Report was prepared to provide the foundation for the Single-Shell Tank (SST) Retrieval Program, a new program responsible for waste removal for the SSTS. The SST Retrieval Program is integrated with other Tank Waste Remediation System activities that provide the management, technical, and operations elements associated with planning and execution of SST and SST Farm retrieval and closure. This Mission Analysis Report provides the basis and strategy for developing a program plan for SST retrieval. This Mission Analysis Report responds to a US Department of Energy request for an alternative single-shell tank retrieval approach (Taylor 1997).

  11. RETRIEVAL EQUIPMENT DESCRIPTIONS

    SciTech Connect

    J. Steinhoff

    1997-08-25

    The objective and the scope of this document are to list and briefly describe the major mobile equipment necessary for waste package (WP) retrieval from the proposed subsurface nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the equipment are explained and summarized in the individual subsections of this document. There are no quality assurance requirements or QA controls in this document. Retrieval under normal conditions is accomplished with the same fleet of equipment as is used for emplacement. Descriptions of equipment used for retrieval under normal conditions is found in Emplacement Equipment Descriptions, DI: BCAF00000-01717-5705-00002 (a document in progress). Equipment used for retrieval under abnormal conditions is addressed in this document and consists of the following: (1) Inclined Plane Hauler; (2) Bottom Lift Transporter; (3) Load Haul Dump (LHD) Loader; (4) Heavy Duty Forklift for Emplacement Drifts; (5) Covered Shuttle Car; (6) Multipurpose Vehicle; and (7) Scaler.

  12. Retrieving Patent Information Online

    ERIC Educational Resources Information Center

    Kaback, Stuart M.

    1978-01-01

    This paper discusses patent information retrieval from online files in terms of types of questions, file contents, coverage, timeliness, and other file variations. CLAIMS, Derwent, WPI, APIPAT and Chemical Abstracts Service are described. (KP)

  13. Information retrieval system

    NASA Technical Reports Server (NTRS)

    Berg, R. F.; Holcomb, J. E.; Kelroy, E. A.; Levine, D. A.; Mee, C., III

    1970-01-01

    Generalized information storage and retrieval system capable of generating and maintaining a file, gathering statistics, sorting output, and generating final reports for output is reviewed. File generation and file maintenance programs written for the system are general purpose routines.

  14. Retrievability Strategy Report

    SciTech Connect

    Gehner, P; Gilstrap, O J; Memory, R D; Wagner, R C

    1997-04-30

    Section 122 of the ''Nuclear Waste Policy Act'' requires that a repository be designed and constructed to permit retrieval of any spent fuel placed in such repository, during an appropriate period of operation of the facility, for one of these reasons: (1) to protect public health and safety, or the environment; and (2) to permit the recovery of the economically valuable contents of such spent fuel. The Act also requires the Secretary to specify an appropriate period of retrievability at the time of the design of a repository. The Secretary has not yet defined any such period. However, the Nuclear Regulatory Commission, in the Code of Federal Regulations Title 10 Part 60.111, requires the design of a geologic repository operations area to allow the retrieval of any or all waste on a reasonable schedule starting at any time up to 50 years after waste operations are initiated. NRC describes a reasonable schedule as one that would permit retrieval in about the same time as it took to construct the repository and emplace the waste. Based on the existing conceptual repository and waste package design and analysis, the Yucca Mountain Project described retrieval operations under normal and abnormal conditions in the 1988 ''Site Characterization Plan (SCP)'' document. In 1991, under the same design assumptions, the Project issued a ''Retrieval Strategy Report for a Potential High-Level Nuclear Waste Repository''. Both the conceptual design of the waste package and the emplacement methods have since changed significantly. This report presents the results of a study to determine whether and to what degree these design and other changes require a revision of the retrieval strategy and, if they do, to recommend a revised strategy. The aim of such a revised strategy was to inform decision makers on how to proceed with design to allow retrievability.

  15. Fuel Retrieval System (FRS) Design Verification

    SciTech Connect

    YANOCHKO, R.M.

    2000-01-27

    This document was prepared as part of an independent review to explain design verification activities already completed, and to define the remaining design verification actions for the Fuel Retrieval System. The Fuel Retrieval Subproject was established as part of the Spent Nuclear Fuel Project (SNF Project) to retrieve and repackage the SNF located in the K Basins. The Fuel Retrieval System (FRS) construction work is complete in the KW Basin, and start-up testing is underway Design modifications and construction planning are also underway for the KE Basin. An independent review of the design verification process as applied to the K Basin projects was initiated in support of preparation for the SNF Project operational readiness review (ORR).

  16. Retrieval with gene queries

    PubMed Central

    Sehgal, Aditya K; Srinivasan, Padmini

    2006-01-01

    Background Accuracy of document retrieval from MEDLINE for gene queries is crucially important for many applications in bioinformatics. We explore five information retrieval-based methods to rank documents retrieved by PubMed gene queries for the human genome. The aim is to rank relevant documents higher in the retrieved list. We address the special challenges faced due to ambiguity in gene nomenclature: gene terms that refer to multiple genes, gene terms that are also English words, and gene terms that have other biological meanings. Results Our two baseline ranking strategies are quite similar in performance. Two of our three LocusLink-based strategies offer significant improvements. These methods work very well even when there is ambiguity in the gene terms. Our best ranking strategy offers significant improvements on three different kinds of ambiguities over our two baseline strategies (improvements range from 15.9% to 17.7% and 11.7% to 13.3% depending on the baseline). For most genes the best ranking query is one that is built from the LocusLink (now Entrez Gene) summary and product information along with the gene names and aliases. For others, the gene names and aliases suffice. We also present an approach that successfully predicts, for a given gene, which of these two ranking queries is more appropriate. Conclusion We explore the effect of different post-retrieval strategies on the ranking of documents returned by PubMed for human gene queries. We have successfully applied some of these strategies to improve the ranking of relevant documents in the retrieved sets. This holds true even when various kinds of ambiguity are encountered. We feel that it would be very useful to apply strategies like ours on PubMed search results as these are not ordered by relevance in any way. This is especially so for queries that retrieve a large number of documents. PMID:16630348

  17. Neurophysiology of successful encoding and retrieval of source memory.

    PubMed

    Cansino, Selene; Trejo-Morales, Patricia

    2008-03-01

    Event-related potentials were recorded during encoding, to identify whether brain activity predicts subsequent retrieval of spatial source information, and during retrieval, to investigate the neural correlates of successful and unsuccessful spatial context recollection. The amplitude registered during encoding for study items that were later recognized and assigned a correct source judgment was more positive than the amplitude for recognized items given incorrect source judgments; this difference started 480 msec poststimulus, predominantly at central and anterior sites. During retrieval, the waveform was more positive from 250 to 1,600 msec poststimulus when the brain had retrieved episodic information successfully than when it had failed. These findings indicate that brain electrical activity recorded during the first presentation of an item within its context predicts the subsequent retrieval of the specific spatial context. During retrieval, brain activity differed quantitatively at anterior sites and qualitatively at posterior sites according to the accuracy of source memory. PMID:18405049

  18. Assessment of alternatives for management of ORNL retrievable transuranic waste. Nuclear Waste Program: transuranic waste (Activity No. AR 05 15 15 0; ONL-WT04)

    SciTech Connect

    Not Available

    1980-10-01

    Since 1970, solid waste with TRU or U-233 contamination in excess of 10 ..mu..Ci per kilogram of waste has been stored in a retrievable fashion at ORNL, such as in ss drums, concrete casks, and ss-lined wells. This report describes the results of a study performed to identify and evaluate alternatives for management of this waste and of the additional waste projected to be stored through 1995. The study was limited to consideration of the following basic strategies: Strategy 1: Leave waste in place as is; Strategy 2: Improve waste confinement; and Strategy 3: Retrieve waste and process for shipment to a Federal repository. Seven alternatives were identified and evaluated, one each for Strategies 1 and 2 and five for Strategy 3. Each alternative was evaluated from the standpoint of technical feasibility, cost, radiological risk and impact, regulatory factors and nonradiological environmental impact.

  19. RETRIEVAL & TREATMENT OF HANFORD TANK WASTE

    SciTech Connect

    EACKER, J.A.; SPEARS, J.A.; STURGES, M.H.; MAUSS, B.M.

    2006-01-20

    The Hanford Tank Farms contain 53 million gal of radioactive waste accumulated during over 50 years of operations. The waste is stored in 177 single-shell and double-shell tanks in the Hanford 200 Areas. The single-shell tanks were put into operation from the early 1940s through the 1960s with wastes received from several generations of processing facilities for the recovery of plutonium and uranium, and from laboratories and other ancillary facilities. The overall hanford Tank Farm system represents one of the largest nuclear legacies in the world driving towards completion of retrieval and treatment in 2028 and the associated closure activity completion by 2035. Remote operations, significant radiation/contamination levels, limited access, and old facilities are just some of the challenges faced by retrieval and treatment systems. These systems also need to be able to successfully remove 99% or more of the waste, and support waste treatment, and tank closure. The Tank Farm retrieval program has ramped up dramatically in the past three years with design, fabrication, installation, testing, and operations ongoing on over 20 of the 149 single-shell tanks. A variety of technologies are currently being pursued to retrieve different waste types, applications, and to help establish a baseline for recovery/operational efficiencies. The paper/presentation describes the current status of retrieval system design, fabrication, installation, testing, readiness, and operations, including: (1) Saltcake removal progress in Tanks S-102, S-109, and S-112 using saltcake dissolution, modified sluicing, and high pressure water lancing techniques; (2) Sludge vacuum retrieval experience from Tanks C-201, C-202, C-203, and C-204; (3) Modified sluicing experience in Tank C-103; (4) Progress on design and installation of the mobile retrieval system for sludge in potentially leaking single-shell tanks, particularly Tank C-101; and (5) Ongoing installation of various systems in the next

  20. Retrieving Product Documentation Online.

    ERIC Educational Resources Information Center

    Racine, Sam J.; Crandall, Irving B.

    2001-01-01

    Discusses demands users face when searching for information in online libraries of product documentation. Demonstrates how physical libraries provide a helpful metaphor for design. Offers heuristics and a conceptual prototype for facilitating electronic document retrieval. Argues that the search form itself should communicate the way materials are…

  1. Feedback in Information Retrieval.

    ERIC Educational Resources Information Center

    Spink, Amanda; Losee, Robert M.

    1996-01-01

    As Information Retrieval (IR) has evolved, it has become a highly interactive process, rooted in cognitive and situational contexts. Consequently the traditional cybernetic-based IR model does not suffice for interactive IR or the human approach to IR. Reviews different views of feedback in IR and their relationship to cybernetic and social…

  2. Information Retrieval by Television.

    ERIC Educational Resources Information Center

    Billowes, C. A.

    1968-01-01

    Bell Canada, the Public School and Collegiate Institute Boards of Ottawa, and the Ontario Institute for Studies in Education are collaborating on an educational television project which will provide a retrieval system that can supply any given program at any time under the control of the classroom teacher. Four schools in Ottawa will participate…

  3. Information Retrieval Techniques.

    ERIC Educational Resources Information Center

    Kantor, Paul B.

    1994-01-01

    Identifies current trends in the automation of indexing, of information retrieval, and of interaction between the system and the users. Topics discussed include location, navigation, and indexing; digital libraries; matching documents to queries; weight of concepts; query structure, including fuzzy sets; algorithms; stemming; clustering; users'…

  4. Dropout Retrieval Programs.

    ERIC Educational Resources Information Center

    Salerno, Anne; Fink, Mary

    This paper describes 15 dropout retrieval programs that have components with potential for helping migrant dropout youth return to an educational program. Each profile contains information on eligibility, identification or recruitment method, funding, services, and contacts. In addition, each program is categorized as to type of sponsoring…

  5. OPAC Missing Record Retrieval.

    ERIC Educational Resources Information Center

    Johnson, Karl E.

    1996-01-01

    When the Higher Education Library Information Network of Rhode Island transferred members' bibliographic data into a shared online public access catalog (OPAC), 10% of the University of Rhode Island's monograph records were missing. This article describes the consortium's attempts to retrieve records from the database and the effectiveness of…

  6. Information Retrieval Systems.

    ERIC Educational Resources Information Center

    National Archives and Records Service (GSA), Washington, DC. Office of Records Management.

    Descriptions of representative nonconventional information systems in use today are given in order to provide managers, management analysts, supervisors, and others with ideas as to how they might improve the dissemination, storage, and retrieval of information in their offices. No attempt was made to evaluate the relative merits of the systems…

  7. Collaborative Information Retrieval.

    ERIC Educational Resources Information Center

    Bruce, Harry; Fidel, Raya

    1999-01-01

    Researchers from the University of Washington, Microsoft Research, Boeing, and Risoe National Laboratory in Denmark have embarked on a project to explore the manifestations of Collaborative Information Retrieval (CIR) in work settings and to propose technological innovations and organizational changes that can support, facilitate, and improve CIR.…

  8. Music Information Retrieval.

    ERIC Educational Resources Information Center

    Downie, J. Stephen

    2003-01-01

    Identifies MIR (Music Information Retrieval) computer system problems, historic influences, current state-of-the-art, and future MIR solutions through an examination of the multidisciplinary approach to MIR. Highlights include pitch; temporal factors; harmonics; tone; editorial, textual, and bibliographic facets; multicultural factors; locating…

  9. Neuromodulatory signaling in hippocampus-dependent memory retrieval.

    PubMed

    Thomas, Steven A

    2015-04-01

    Considerable advances have been made toward understanding the molecular signaling events that underlie memory acquisition and consolidation. In contrast, less is known about memory retrieval, despite its necessity for utilizing learned information. This review focuses on neuromodulatory and intracellular signaling events that underlie memory retrieval mediated by the hippocampus, for which the most information is currently available. Among neuromodulators, adrenergic signaling is required for the retrieval of various types of hippocampus-dependent memory. Although they contribute to acquisition and/or consolidation, cholinergic and dopaminergic signaling are generally not required for retrieval. Interestingly, while not required for retrieval, serotonergic and opioid signaling may actually constrain memory retrieval. Roles for histamine and non-opioid neuropeptides are currently unclear but possible. A critical effector of adrenergic signaling in retrieval is reduction of the slow afterhyperpolarization mediated by β1 receptors, cyclic AMP, protein kinase A, Epac, and possibly ERK. In contrast, stress and glucocorticoids impair retrieval by decreasing cyclic AMP, mediated in part by the activation of β2 -adrenergic receptors. Clinically, alterations in neuromodulatory signaling and in memory retrieval occur in Alzheimer's disease, Down syndrome, depression, and post-traumatic stress disorder, and recent evidence has begun to link changes in neuromodulatory signaling with effects on memory retrieval. PMID:25475876

  10. Alcohol and Memory: Retrieval Processes

    ERIC Educational Resources Information Center

    Birnbaum, Isabel M.; And Others

    1978-01-01

    The influence of alcohol intoxication on the retrieval of information from memory was investigated in nonalcoholic subjects Intoxicated subjects recalled fewer categories and words within categories. The retrieval stage of memory did not appear to be affected by alcohol. (SW)

  11. Mobile medical image retrieval

    NASA Astrophysics Data System (ADS)

    Duc, Samuel; Depeursinge, Adrien; Eggel, Ivan; Müller, Henning

    2011-03-01

    Images are an integral part of medical practice for diagnosis, treatment planning and teaching. Image retrieval has gained in importance mainly as a research domain over the past 20 years. Both textual and visual retrieval of images are essential. In the process of mobile devices becoming reliable and having a functionality equaling that of formerly desktop clients, mobile computing has gained ground and many applications have been explored. This creates a new field of mobile information search & access and in this context images can play an important role as they often allow understanding complex scenarios much quicker and easier than free text. Mobile information retrieval in general has skyrocketed over the past year with many new applications and tools being developed and all sorts of interfaces being adapted to mobile clients. This article describes constraints of an information retrieval system including visual and textual information retrieval from the medical literature of BioMedCentral and of the RSNA journals Radiology and Radiographics. Solutions for mobile data access with an example on an iPhone in a web-based environment are presented as iPhones are frequently used and the operating system is bound to become the most frequent smartphone operating system in 2011. A web-based scenario was chosen to allow for a use by other smart phone platforms such as Android as well. Constraints of small screens and navigation with touch screens are taken into account in the development of the application. A hybrid choice had to be taken to allow for taking pictures with the cell phone camera and upload them for visual similarity search as most producers of smart phones block this functionality to web applications. Mobile information access and in particular access to images can be surprisingly efficient and effective on smaller screens. Images can be read on screen much faster and relevance of documents can be identified quickly through the use of images contained in

  12. Satellite services and orbital retrieval

    NASA Technical Reports Server (NTRS)

    Adornato, R. J.

    1985-01-01

    Within the capabilities of the Space Shuttle Orbiter, a broad range of services which can be made available to the satellite user community as summarized. Payload deployment, close proximity retrieval, and a number of other mission related functions are discussed. The focus here is on close proximity retrieval and retrieval of payloads in higher energy low Earth orbits.

  13. A Visual Information Retrieval Tool.

    ERIC Educational Resources Information Center

    Zhang, Jin

    2000-01-01

    Discussion of visualization for information retrieval, that transforms unseen internal semantic representation of a document collection into visible geometric displays, focuses on DARE (Distance Angle Retrieval Environment). Highlights include expression of information need; interpretation and manipulation of information retrieval models; ranking…

  14. Language Processing in Information Retrieval.

    ERIC Educational Resources Information Center

    Doszkocs, Tamase

    1986-01-01

    Examines role and contributions of natural-language processing in information retrieval and artificial intelligence research in context of large operational information retrieval systems and services. State-of-the-art information retrieval systems combining the functional capabilities of conventional inverted file term adjacency approach with…

  15. Test Objectives for the Saltcake Dissolution Retrieval Demonstration

    SciTech Connect

    DEFIGH PRICE, C.

    2000-09-22

    This document describes the objectives the Saltcake Dissolution Retrieval Demonstration. The near term strategy for single-shell tank waste retrieval activities has shifted from focusing on maximizing the number of tanks entered for retrieval (regardless of waste volume or content) to a focus on scheduling the retrieval of wastes from those single-shell tanks with a high volume of contaminants of concern. These contaminants are defined as mobile, long-lived radionuclides that have a potential of reaching the groundwater and the Columbia River. This strategy also focuses on the performance of key retrieval technology demonstrations, including the Saltcake Dissolution Retrieval Demonstration, in a variety of waste forms and tank farm locations to establish a technical basis for future work. The work scope will also focus on the performance of risk assessment, retrieval performance evaluations (RPE) and incorporating vadose zone characterization data on a tank-by-tank basis, and on updating tank farm closure/post closure work plans. The deployment of a retrieval technology other than Past-Practice Sluicing (PPS) allows determination of limits of technical capabilities, as well as, providing a solid planning basis for future SST retrievals. This saltcake dissolution technology deployment test will determine if saltcake dissolution is a viable retrieval option for SST retrieval. CH2M Hill Hanford Group (CHG) recognizes the SST retrieval mission is key to the success of the River Protection Project (RPP) and the overall completion of the Hanford Site cleanup. The objectives outlined in this document will be incorporated into and used to develop the test and evaluation plan for saltcake dissolution retrievals. The test and evaluation plan will be developed in fiscal year 2001.

  16. Practical quantum retrieval games

    NASA Astrophysics Data System (ADS)

    Arrazola, Juan Miguel; Karasamanis, Markos; Lütkenhaus, Norbert

    2016-06-01

    Complex cryptographic protocols are often constructed from simpler building blocks. In order to advance quantum cryptography, it is important to study practical building blocks that can be used to develop new protocols. An example is quantum retrieval games (QRGs), which have broad applicability and have already been used to construct quantum money schemes. In this work, we introduce a general construction of quantum retrieval games based on the hidden matching problem and show how they can be implemented in practice using available technology. More precisely, we provide a general method to construct (1-out-of-k ) QRGs, proving that their cheating probabilities decrease exponentially in k . In particular, we define QRGs based on coherent states of light, which can be implemented even in the presence of experimental imperfections. Our results constitute a tool in the arsenal of the practical quantum cryptographer.

  17. Magnetic junk retriever

    SciTech Connect

    Moseley, M.D.

    1980-10-07

    An improved magnetic junk retriever arranged to magnetize a drill bit just prior to its removal from the bottom of the well bore. A wound, electromagnet subassembly is connected between the drill bit and the drill collar. A battery-pack tool is used to energize the electromagnet by lowering the tool through the bore of the drill pipe and collars to contact pins projecting into the bore of the sub. Energizing the electromagnet causes the drill bit to be magnetized.

  18. Satellite retrieval system

    NASA Technical Reports Server (NTRS)

    Pruett, E. C.; Robertson, K. B.; Loughead, T. E. (Inventor)

    1983-01-01

    A satellite retrieval system with first and second pairs of coacting parallel bars are separately mounted in spaced parallel planes on the front of a spacecraft. The bars of one pair are at right angles to bars of the other pair, and together the two pairs of bars effect a variable aperture adapted to close around a rod extending from a second spacecraft to effect the capture of the latter.

  19. REMOTE RETRIEVING TOOL

    DOEpatents

    Fromm, L.W. Jr.

    1958-08-19

    A retrieving tool is described to securely grasp an object for emplacement in, or withdrawal from, an elongated tube. The object is grasped by hooks actuated by a wedge and cann mechanism. The mechanism on the end of a long rodlike structure is controlled by levers or bars at the access end of the tube. This device is particularly useful for positioning fuel elements within a reactor core.

  20. Oscillatory Correlates of Retrieval-Induced Forgetting in Recognition Memory

    ERIC Educational Resources Information Center

    Spitzer, Bernhard; Hanslmayr, Simon; Opitz, Bertram; Mecklinger, Axel; Bauml, Karl-Heinz

    2009-01-01

    Retrieval practice on a subset of previously studied material enhances later memory for practiced material but can inhibit memory for related unpracticed material. The present study examines the effects of prior retrieval practice on evoked (ERPs) and induced (oscillatory power) measures of electrophysiological activity underlying recognition of…

  1. Modulation of Retrieval Processing Reflects Accuracy of Emotional Source Memory

    ERIC Educational Resources Information Center

    Smith, Adam P. R.; Henson, Richard N. A.; Rugg, Michael D.; Dolan, Raymond J.

    2005-01-01

    There is considerable evidence that encoding and consolidation of memory are modulated by emotion, but the retrieval of emotional memories is not well characterized. Here we manipulated the emotional context with which affectively neutral stimuli were associated during encoding, allowing us to examine neural activity associated with retrieval of…

  2. Simulating Network Retrieval of Arithmetic Facts.

    ERIC Educational Resources Information Center

    Ashcraft, Mark H.

    This report describes a simulation of adults' retrieval of arithmetic facts from a network-based memory representation. The goals of the simulation project are to: demonstrate in specific form the nature of a spreading activation model of mental arithmetic; account for three important reaction time effects observed in laboratory investigations;…

  3. Learning with Retrieval-Based Concept Mapping

    ERIC Educational Resources Information Center

    Blunt, Janell R.; Karpicke, Jeffrey D.

    2014-01-01

    Students typically create concept maps while they view the material they are trying to learn. In these circumstances, concept mapping serves as an elaborative study activity--students are not required to retrieve the material they are learning. In 2 experiments, we examined the effectiveness of concept mapping when it is used as a retrieval…

  4. The Emerging Internationalism of Online Information Retrieval.

    ERIC Educational Resources Information Center

    Summit, Roger K.

    Until 1980 online information retrieval and dissemination services were for the most part based in the United States. Today, however, a variety of information services as well as packet-switched networks are emerging in other countries. Although U.S. developed software still predominates in overall use, activity in Europe and other countries is…

  5. Encoding and Retrieval During Bimanual Rhythmic Coordination

    ERIC Educational Resources Information Center

    Shockley, Kevin; Turvey, Michael T.

    2005-01-01

    In 2 experiments, bimanual 1:1 rhythmic coordination was performed concurrently with encoding or retrieval of word lists. Effects of divided attention (DA) on coordination were indexed by changes in mean relative phase and recurrence measures of shared activity between the 2 limbs. Effects of DA on memory were indexed by deficits in recall…

  6. Retrievable Inferior Vena Cava Filters: Factors that Affect Retrieval Success

    SciTech Connect

    Geisbuesch, Philipp Benenati, James F.; Pena, Constantino S.; Couvillon, Joseph; Powell, Alex; Gandhi, Ripal; Samuels, Shaun; Uthoff, Heiko

    2012-10-15

    Purpose: To report and analyze the indications, procedural success, and complications of retrievable inferior vena cava filters (rIVCF) placement and to identify parameters that influence retrieval attempt and failure. Methods: Between January 2005 and December 2010, a total of 200 patients (80 men, median age 67 years, range 11-95 years) received a rIVCF with the clinical possibility that it could be removed. All patients with rIVCF were prospectively entered into a database and followed until retrieval or a decision not to retrieve the filter was made. A retrospective analysis of this database was performed. Results: Sixty-one percent of patients had an accepted indication for filter placement; 39% of patients had a relative indication. There was a tendency toward a higher retrieval rate in patients with relative indications (40% vs. 55%, P = 0.076). Filter placement was technically successful in all patients, with no procedure-related mortality. The retrieval rate was 53%. Patient age of >80 years (odds ratio [OR] 0.056, P > 0.0001) and presence of malignancy (OR 0.303, P = 0.003) was associated with a significantly reduced probability for attempted retrieval. Retrieval failure occurred in 7% (6 of 91) of all retrieval attempts. A time interval of > 90 days between implantation and attempted retrieval was associated with retrieval failure (OR 19.8, P = 0.009). Conclusions: Patient age >80 years and a history of malignancy are predictors of a reduced probability for retrieval attempt. The rate of retrieval failure is low and seems to be associated with a time interval of >90 days between filter placement and retrieval.

  7. Multisensor Retrieval of Atmospheric Properties.

    NASA Astrophysics Data System (ADS)

    Boba Stankov, B.

    1998-09-01

    A new method, Multisensor Retrieval of Atmospheric Properties (MRAP), is presented for deriving vertical profiles of atmospheric parameters throughout the troposphere. MRAP integrates measurements from multiple, diverse, remote sensing, and in situ instruments, the combination of which provides better capabilities than any instrument alone. Since remote sensors can deliver measurements automatically and continuously with high time resolution, MRAP provides better coverage than traditional rawinsondes. MRAP's design is flexible, being capable of incorporating measurements from different instruments in order to take advantage of new or developing advanced sensor technology. Furthermore, new or alternative atmospheric parameters for a variety of applications may be easily added as products of MRAP.A combination of passive radiometric, active radar, and in situ observations provide the best temperature and humidity profile measurements. Therefore, MRAP starts with a traditional, radiometer-based, physical retrieval algorithm provided by the International TOVS (TIROS-N Operational Vertical Sounder) Processing Package (ITPP) that constrains the retrieved profiles to agree with brightness temperature measurements. The first-guess profiles required by the ITPP's iterative retrieval algorithm are obtained by using a statistical inversion technique and ground-based remote sensing measurements. Because the individual ground-based remote sensing measurements are usually of sufficiently high quality, the first-guess profiles by themselves provide a satisfactory solution to establish the atmospheric water vapor and temperature state, and the TOVS data are included to provide profiles with better accuracy at higher levels, MRAP provides a physically consistent mechanism for combining the ground- and space-based humidity and temperature profiles.Data that have been used successfully to retrieve humidity and temperature profiles with MRAP are the following: temperature profiles in

  8. Transuranic (TRU) Waste Phase I Retrieval Plan

    SciTech Connect

    MCDONALD, K.M.

    2000-09-28

    From 1970 to 1987, TRU and suspect TRU wastes at Hanford were placed in the SWBG. At the time of placement in the SWBG these wastes were not regulated under existing Resource Conservation and Recovery Act (RCRA) regulations, since they were generated and disposed of prior to the effective date of RCRA at the Hanford Site (1987). From the standpoint of DOE Order 5820.2A1, the TRU wastes are considered retrievably stored, and current plans are to retrieve these wastes for shipment to WIPP for disposal. This plan provides a strategy for the Phase I retrieval that meets the intent of TPA milestone M-91 and Project W-113, and incorporates the lessons learned during TRU retrieval campaigns at Hanford, LANL, and SRS. As in the original Project W-113 plans, the current plan calls for examination of approximately 10,000 suspect-TRU drums located in the 218-W-4C burial ground followed by the retrieval of those drums verified to contain TRU waste. Unlike the older plan, however, this plan proposes an open-air retrieval scenario similar to those used for TRU drum retrieval at LANL and SRS. Phase I retrieval consists of the activities associated with the assessment of approximately 10,000 55-gallon drums of suspect TRU-waste in burial ground 218-W-4C and the retrieval of those drums verified to contain TRU waste. Four of the trenches in 218-W-4C (Trenches 1, 4, 20, and 29) are prime candidates for Phase I retrieval because they contain large numbers of suspect TRU drums, stacked from 2 to 5 drums high, on an asphalt pad. In fact, three of the trenches (Trenches 1 , 20, and 29) contain waste that has not been covered with soil, and about 1500 drums can be retrieved without excavation. The other three trenches in 218-W-4C (Trenches 7, 19, and 24) are not candidates for Phase I retrieval because they contain significant numbers of boxes. Drums will be retrieved from the four candidate trenches, checked for structural integrity, overpacked, if necessary, and assayed at the burial

  9. Reward eliminates retrieval-induced forgetting

    PubMed Central

    Imai, Hisato; Kim, Dongho; Sasaki, Yuka; Watanabe, Takeo

    2014-01-01

    Although it is well known that reward enhances learning and memory, how extensively such enhancement occurs remains unclear. To address this question, we examined how reward influences retrieval-induced forgetting (RIF) in which the retrieval of a nonpracticed item under the same category as a practiced item is worse than the retrieval of a nonpracticed item outside the category. Subjects were asked to try to encode category-exemplar pairs (e.g., FISH–salmon). Then, they were presented with a category name and a two-letter word stem (e.g., FISH–sa) and were asked to complete an encoded word (retrieval practice). For a correct response, apple juice was given as a reward in the reward condition and a beeping sound was presented in the no-reward condition. Finally, subjects were asked to report whether each exemplar had been presented in the first phase. RIF was replicated in the no-reward condition. However, in the reward condition, RIF was eliminated. These results suggest that reward enhances processing of retrieval of unpracticed members by mechanisms such as spreading activation within the same category, irrespective of whether items were practiced or not. PMID:25404297

  10. JURASSIC Retrieval Processing

    NASA Astrophysics Data System (ADS)

    Blank, J.; Ungermann, J.; Guggenmoser, T.; Kaufmann, M.; Riese, M.

    2012-04-01

    The Gimballed Limb Observer for Radiance Imaging in the Atmosphere (GLORIA) is an aircraft based infrared limb-sounder. This presentation will give an overview of the retrieval techniques used for the analysis of data produced by the GLORIA instrument. For data processing, the JUelich RApid Spectral SImulation Code 2 (JURASSIC2) was developed. It consists of a set of programs to retrieve atmospheric profiles from GLORIA measurements. The GLORIA Michelson interferometer can run with a wide range of parameters. In the dynamics mode, spectra are generate with a medium spectral and a very high temporal and spatial resolution. Each sample can contain thousands of spectral lines for each contributing trace gas. In the JURASSIC retrieval code this is handled by using a radiative transport model based on the Emissivity Growth Approximation. Deciding which samples should be included in the retrieval is a non-trivial task and requires specific domain knowledge. To ease this problem we developed an automatic selection program by analysing the Shannon information content. By taking into account data for all relevant trace gases and instrument effects, optimal integrated spectral windows are computed. This includes considerations for cross-influence of trace gases, which has non-obvious consequence for the contribution of spectral samples. We developed methods to assess the influence of spectral windows on the retrieval. While we can not exhaustively search the whole range of possible spectral sample combinations, it is possible to optimize information content using a genetic algorithm. The GLORIA instrument is mounted with a viewing direction perpendicular to the flight direction. A gimbal frame makes it possible to move the instrument 45° to both direction. By flying on a circular path, it is possible to generate images of an area of interest from a wide range of angles. These can be analyzed in a 3D-tomographic fashion, which yields superior spatial resolution along line of

  11. Guenter Tulip Filter Retrieval Experience: Predictors of Successful Retrieval

    SciTech Connect

    Turba, Ulku Cenk Arslan, Bulent Meuse, Michael Sabri, Saher; Macik, Barbara Gail

    2010-08-15

    We report our experience with Guenter Tulip filter placement indications, retrievals, and procedural problems, with emphasis on alternative retrieval techniques. We have identified 92 consecutive patients in whom a Guenter Tulip filter was placed and filter removal attempted. We recorded patient demographic information, filter placement and retrieval indications, procedures, standard and nonstandard filter retrieval techniques, complications, and clinical outcomes. The mean time to retrieval for those who experienced filter strut penetration was statistically significant [F(1,90) = 8.55, p = 0.004]. Filter strut(s) IVC penetration and successful retrieval were found to be statistically significant (p = 0.043). The filter hook-IVC relationship correlated with successful retrieval. A modified guidewire loop technique was applied in 8 of 10 cases where the hook appeared to penetrate the IVC wall and could not be engaged with a loop snare catheter, providing additional technical success in 6 of 8 (75%). Therefore, the total filter retrieval success increased from 88 to 95%. In conclusion, the Guenter Tulip filter has high successful retrieval rates with low rates of complication. Additional maneuvers such as a guidewire loop method can be used to improve retrieval success rates when the filter hook is endothelialized.

  12. Monetary rewards influence retrieval orientations.

    PubMed

    Halsband, Teresa M; Ferdinand, Nicola K; Bridger, Emma K; Mecklinger, Axel

    2012-09-01

    Reward anticipation during learning is known to support memory formation, but its role in retrieval processes is so far unclear. Retrieval orientations, as a reflection of controlled retrieval processing, are one aspect of retrieval that might be modulated by reward. These processes can be measured using the event-related potentials (ERPs) elicited by retrieval cues from tasks with different retrieval requirements, such as via changes in the class of targeted memory information. To determine whether retrieval orientations of this kind are modulated by reward during learning, we investigated the effects of high and low reward expectancy on the ERP correlates of retrieval orientation in two separate experiments. The reward manipulation at study in Experiment 1 was associated with later memory performance, whereas in Experiment 2, reward was directly linked to accuracy in the study task. In both studies, the participants encoded mixed lists of pictures and words preceded by high- or low-reward cues. After 24 h, they performed a recognition memory exclusion task, with words as the test items. In addition to a previously reported material-specific effect of retrieval orientation, a frontally distributed, reward-associated retrieval orientation effect was found in both experiments. These findings suggest that reward motivation during learning leads to the adoption of a reward-associated retrieval orientation to support the retrieval of highly motivational information. Thus, ERP retrieval orientation effects not only reflect retrieval processes related to the sought-for materials, but also relate to the reward conditions with which items were combined during encoding. PMID:22547161

  13. Retrievable Inferior Vena Cava Filters in Patients with Cancer: Complications and Retrieval Success Rate

    PubMed Central

    Casanegra, Ana I.; Landrum, Lisa M.; Tafur, Alfonso J.

    2016-01-01

    Active cancer (ACa) is strongly associated with venous thromboembolism and bleeding. Retrievable inferior vena cava filters (RIVCF) are frequently placed in these patients when anticoagulation cannot be continued. Objectives. To describe the complications and retrieval rate of inferior vena cava filters in patients with ACa. Methods. Retrospective review of 251 consecutive patients with RIVCF in a single institution. Results. We included 251 patients with RIVCF with a mean age of 58.1 years and a median follow-up of 5.4 months (164 days, IQR: 34–385). Of these patients 32% had ACa. There were no differences in recurrence rate of DVT between patients with ACa and those without ACa (13% versus 17%, p = ns). Also, there were no differences in major filter complications (11% ACa versus 7% no ACa, p = ns). The filter retrieval was not different between groups (log-rank = 0.16). Retrieval rate at 6 months was 49% in ACa patients versus 64% in patients without ACa (p = ns). Filter retrieval was less frequent in ACa patients with metastatic disease (p < 0.01) or a nonsurgical indication for filter placement (p = 0.04). Conclusions. No differences were noted in retrieval rate, recurrent DVT, or filter complications between the two groups. ACa should not preclude the use of RIVCF. PMID:26904290

  14. Music retrieval in ICOR

    NASA Astrophysics Data System (ADS)

    Finsterle, Lutz; Fischer, Stephan; Rimac, Ivica; Steinmetz, Ralf

    1999-08-01

    In this paper we describe music retrieval in ICOR, a project of Darmstadt TU. It is the goal of ICOR to find new interfaces to support applications of music video and music CDs. Although the project consists of audio and video analysis we concentrate on a description of the audio algorithms in this paper. We describe our MPEG-7 like data structure to store meta information for music pieces and explain which algorithms we use to analyze the content of music pieces automatically. We currently use an applause detection to distinguish live music from studio recordings, a genre classifier to distinguish pieces with beats form classical music, and a singer recognition.

  15. 2. VIEW OF INTERIOR OF XY RETRIEVER. THE XY RETRIEVER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF INTERIOR OF X-Y RETRIEVER. THE X-Y RETRIEVER WAS HOUSED IN MODULE K AND WAS USED TO SORT AND RETRIEVE PLUTONIUM METAL FROM A STORAGE VAULT FOR DISTRIBUTION TO OTHER PROCESSES IN BUILDING 707. (11/29/88) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

  16. Competitive Semantic Memory Retrieval: Temporal Dynamics Revealed by Event-Related Potentials

    PubMed Central

    Hellerstedt, Robin; Johansson, Mikael

    2016-01-01

    Memories compete for retrieval when they are related to a common retrieval cue. Previous research has shown that retrieval of a target memory may lead to subsequent retrieval-induced forgetting (RIF) of currently irrelevant competing memories. In the present study, we investigated the time course of competitive semantic retrieval and examined the neurocognitive mechanisms underlying RIF. We contrasted two theoretical accounts of RIF by examining a critical aspect of this memory phenomenon, namely the extent to which it depends on successful retrieval of the target memory. Participants first studied category-exemplar word-pairs (e.g. Fruit—Apple). Next, we recorded electrophysiological measures of brain activity while the participants performed a competitive semantic cued-recall task. In this task, the participants were provided with the studied categories but they were instructed to retrieve other unstudied exemplars (e.g. Fruit—Ma__?). We investigated the event-related potential (ERP) correlates of retrieval success by comparing ERPs from successful and failed retrieval trials. To isolate the ERP correlates of continuous retrieval attempts from the ERP correlates of retrieval success, we included an impossible retrieval condition, with incompletable word-stem cues (Drinks—Wy__) and compared it with a non-retrieval presentation baseline condition (Occupation—Dentist). The participants’ memory for all the studied exemplars was tested in the final phase of the experiment. Taken together, the behavioural results suggest that RIF is independent of target retrieval. Beyond investigating the mechanisms underlying RIF, the present study also elucidates the temporal dynamics of semantic cued-recall by isolating the ERP correlates of retrieval attempt and retrieval success. The ERP results revealed that retrieval attempt is reflected in a late posterior negativity, possibly indicating construction of candidates for completing the word-stem cue and retrieval

  17. Enhanced Information Retrieval Using AJAX

    NASA Astrophysics Data System (ADS)

    Kachhwaha, Rajendra; Rajvanshi, Nitin

    2010-11-01

    Information Retrieval deals with the representation, storage, organization of, and access to information items. The representation and organization of information items should provide the user with easy access to the information with the rapid development of Internet, large amounts of digitally stored information is readily available on the World Wide Web. This information is so huge that it becomes increasingly difficult and time consuming for the users to find the information relevant to their needs. The explosive growth of information on the Internet has greatly increased the need for information retrieval systems. However, most of the search engines are using conventional information retrieval systems. An information system needs to implement sophisticated pattern matching tools to determine contents at a faster rate. AJAX has recently emerged as the new tool such the of information retrieval process of information retrieval can become fast and information reaches the use at a faster pace as compared to conventional retrieval systems.

  18. Retrieval practice produces more learning than elaborative studying with concept mapping.

    PubMed

    Karpicke, Jeffrey D; Blunt, Janell R

    2011-02-11

    Educators rely heavily on learning activities that encourage elaborative studying, whereas activities that require students to practice retrieving and reconstructing knowledge are used less frequently. Here, we show that practicing retrieval produces greater gains in meaningful learning than elaborative studying with concept mapping. The advantage of retrieval practice generalized across texts identical to those commonly found in science education. The advantage of retrieval practice was observed with test questions that assessed comprehension and required students to make inferences. The advantage of retrieval practice occurred even when the criterial test involved creating concept maps. Our findings support the theory that retrieval practice enhances learning by retrieval-specific mechanisms rather than by elaborative study processes. Retrieval practice is an effective tool to promote conceptual learning about science. PMID:21252317

  19. EM-21 Retrieval Knowledge Center: Waste Retrieval Challenges

    SciTech Connect

    Fellinger, Andrew P.; Rinker, Michael W.; Berglin, Eric J.; Minichan, Richard L.; Poirier, Micheal R.; Gauglitz, Phillip A.; Martin, Bruce A.; Hatchell, Brian K.; Saldivar, Eloy; Mullen, O Dennis; Chapman, Noel F.; Wells, Beric E.; Gibbons, Peter W.

    2009-04-10

    EM-21 is the Waste Processing Division of the Office of Engineering and Technology, within the U.S. Department of Energy’s (DOE) Office of Environmental Management (EM). In August of 2008, EM-21 began an initiative to develop a Retrieval Knowledge Center (RKC) to provide the DOE, high level waste retrieval operators, and technology developers with centralized and focused location to share knowledge and expertise that will be used to address retrieval challenges across the DOE complex. The RKC is also designed to facilitate information sharing across the DOE Waste Site Complex through workshops, and a searchable database of waste retrieval technology information. The database may be used to research effective technology approaches for specific retrieval tasks and to take advantage of the lessons learned from previous operations. It is also expected to be effective for remaining current with state-of-the-art of retrieval technologies and ongoing development within the DOE Complex. To encourage collaboration of DOE sites with waste retrieval issues, the RKC team is co-led by the Savannah River National Laboratory (SRNL) and the Pacific Northwest National Laboratory (PNNL). Two RKC workshops were held in the Fall of 2008. The purpose of these workshops was to define top level waste retrieval functional areas, exchange lessons learned, and develop a path forward to support a strategic business plan focused on technology needs for retrieval. The primary participants involved in these workshops included retrieval personnel and laboratory staff that are associated with Hanford and Savannah River Sites since the majority of remaining DOE waste tanks are located at these sites. This report summarizes and documents the results of the initial RKC workshops. Technology challenges identified from these workshops and presented here are expected to be a key component to defining future RKC-directed tasks designed to facilitate tank waste retrieval solutions.

  20. Studies in remotely sensed geophysical parameter retrieval and analysis

    NASA Technical Reports Server (NTRS)

    Perkey, Donald J.

    1993-01-01

    This report describes Universities Space Research Association (USRA) activities in support of the Geophysical Parameter Retrieval and Analysis studies. Specifically it addresses personnel assigned to the effort, travel, consultant participants, technical progress, and contract spending.

  1. Final report for the cryogenic retrieval demonstration

    SciTech Connect

    Valentich, D.J.; Yokuda, E.L.

    1992-09-01

    This report documents a demonstration of a proposed buried transuranic waste retrieval concept that uses cryogenic ground freezing and remote excavation. At the Idaho National Engineering Laboratory (INEL), there are over 8 million ft{sup 3} of intermingled soil and transuranic (TRU) wastes in shallow land burial, and retrieval of the material is one of the options being considered by the Buried Waste Integrated Demonstration for the Environmental Restoration program. Cryogenically freezing contaminated soil and buried waste has been proposed as a way to greatly reduce or eliminate the climate the threat of contamination spread during retrieval activities. In support of this idea, a demonstration of an innovative ground freezing and retrieval technology was performed at the INEL. This initial demonstration was held near the Radioactive Waste Management Complex at a ``cold test pit`` that was built in 1988 as a test bed for the demonstration of retrieval contamination control technologies. This pit is not contaminated with any radioactive or hazardous wastes. Barrels and boxes filled with metals, plastics, tools, paper, cloth, etc. configured in the same manner as expected in contaminated pits and trenches are buried at the cold test pit. After design, fabrication, and shop testing, Sonsub mobilized to the field in early July 1992 to perform the field demonstration. It was planned to freeze and extract four pits, each 9 {times} 9 {times} 10 ft. Each pit represented a different configuration of buried waste (stacked boxes, stacked barrels, random dumped barrels and boxes, and random dumped barrels). Sonsub`s proposed technology consisted of driving a series of freeze pipes into the soil and waste, using liquid nitrogen to freeze the mass, and extracting the soil and debris using a series of remote operated, bridge crane mounted tools. In conjunction with the freezing and removal activities, temperature and moisture measurements, and air monitoring were performed.

  2. Final report for the cryogenic retrieval demonstration

    SciTech Connect

    Valentich, D.J.; Yokuda, E.L.

    1992-09-01

    This report documents a demonstration of a proposed buried transuranic waste retrieval concept that uses cryogenic ground freezing and remote excavation. At the Idaho National Engineering Laboratory (INEL), there are over 8 million ft[sup 3] of intermingled soil and transuranic (TRU) wastes in shallow land burial, and retrieval of the material is one of the options being considered by the Buried Waste Integrated Demonstration for the Environmental Restoration program. Cryogenically freezing contaminated soil and buried waste has been proposed as a way to greatly reduce or eliminate the climate the threat of contamination spread during retrieval activities. In support of this idea, a demonstration of an innovative ground freezing and retrieval technology was performed at the INEL. This initial demonstration was held near the Radioactive Waste Management Complex at a cold test pit'' that was built in 1988 as a test bed for the demonstration of retrieval contamination control technologies. This pit is not contaminated with any radioactive or hazardous wastes. Barrels and boxes filled with metals, plastics, tools, paper, cloth, etc. configured in the same manner as expected in contaminated pits and trenches are buried at the cold test pit. After design, fabrication, and shop testing, Sonsub mobilized to the field in early July 1992 to perform the field demonstration. It was planned to freeze and extract four pits, each 9 [times] 9 [times] 10 ft. Each pit represented a different configuration of buried waste (stacked boxes, stacked barrels, random dumped barrels and boxes, and random dumped barrels). Sonsub's proposed technology consisted of driving a series of freeze pipes into the soil and waste, using liquid nitrogen to freeze the mass, and extracting the soil and debris using a series of remote operated, bridge crane mounted tools. In conjunction with the freezing and removal activities, temperature and moisture measurements, and air monitoring were performed.

  3. Using optimal estimation method for upper atmospheric Lidar temperature retrieval

    NASA Astrophysics Data System (ADS)

    Zou, Rongshi; Pan, Weilin; Qiao, Shuai

    2016-07-01

    Conventional ground based Rayleigh lidar temperature retrieval use integrate technique, which has limitations that necessitate abandoning temperatures retrieved at the greatest heights due to the assumption of a seeding value required to initialize the integration at the highest altitude. Here we suggests the use of a method that can incorporate information from various sources to improve the quality of the retrieval result. This approach inverts lidar equation via optimal estimation method(OEM) based on Bayesian theory together with Gaussian statistical model. It presents many advantages over the conventional ones: 1) the possibility of incorporating information from multiple heterogeneous sources; 2) provides diagnostic information about retrieval qualities; 3) ability of determining vertical resolution and maximum height to which the retrieval is mostly independent of the a priori profile. This paper compares one-hour temperature profiles retrieved using conventional and optimal estimation methods at Golmud, Qinghai province, China. Results show that OEM results show a better agreement with SABER profile compared with conventional one, in some region it is much lower than SABER profile, which is a very different results compared with previous studies, further studies are needed to explain this phenomenon. The success of applying OEM on temperature retrieval is a validation for using as retrieval framework in large synthetic observation systems including various active remote sensing instruments by incorporating all available measurement information into the model and analyze groups of measurements simultaneously to improve the results.

  4. Telerobotic excavation system for unexploded ordnance retrieval

    SciTech Connect

    Burks, B.L.; Killough, S.M.; Thompson, D.H.; Rossi, R.A.

    1994-12-31

    The small emplacement excavator (SEE) is a ruggedized military vehicle with backhoe and front loader used by the US Army for unexploded ordnance (UXO) retrieval and general utility excavation activities. In order to evaluate the feasibility of removing personnel from the vehicle during high-risk excavation tasks a development and demonstration project was initiated to evaluate performance capabilities of the SEE under telerobotic control. A technology demonstration of the TSEE was conducted at McKinley Range, Redstone Arsenal, Huntsville, Alabama on 13--17 September, 1993. The primary objective of the demonstration was to evaluate and demonstrate the feasibility of remote UXO retrieval. During the demonstration, explosive ordnance disposal specialists were instructed on telerobotic operation of the TSEE, and then were asked to complete a simulated UXO retrieval task. Participants then submitted an evaluation of the system including human factors performance data. This presentation will describe the TSEE, retrieval demonstration, and summarize results of the performance evaluations. Some examples of the results are given below. Seventy percent of the demonstration participants found the tasks were as easy or easier to accomplish utilizing the remote system than with an unmodified system. Similarly, eighty percent of the participants found the TSEE hand controller was as easy or easier to use than the normal manual controls.

  5. An improved glyoxal retrieval from OMI measurements

    NASA Astrophysics Data System (ADS)

    Alvarado, L. M. A.; Richter, A.; Vrekoussis, M.; Wittrock, F.; Hilboll, A.; Schreier, S. F.; Burrows, J. P.

    2014-06-01

    Satellite observations from the SCIAMACHY, GOME-2, and OMI spectrometers have been used to retrieve atmospheric columns of glyoxal (CHOCHO) with the DOAS method. High CHOCHO levels are found over regions with large biogenic and pyrogenic emissions, and hot-spots have been identified over areas of anthropogenic activities. This study focuses on the development of an improved retrieval for CHOCHO from measurements by the OMI instrument. From sensitivity tests, an optimal fitting window and polynomial degree are determined. Two different approaches to reduce the interference of liquid water absorption over oceanic regions are evaluated, achieving significant reduction of negative columns over clear water regions. Moreover, a high temperature absorption cross-section of nitrogen dioxide (NO2) is introduced in the DOAS retrieval to account for potential interferences of NO2 over regions with large anthropogenic emissions, leading to improved fit quality over these areas. A comparison with vertical CHOCHO columns retrieved from measurements of the GOME-2 and SCIAMACHY instruments over continental regions is performed, showing overall good consistency. Using the new OMI CHOCHO data set, the link between fires and glyoxal columns is investigated for two selected regions in Africa. In addition, mapped averages are computed for a fire event in the east of Moscow between mid-July and mid-August 2010. In both cases, enhanced CHOCHO levels are found in close spatial and temporal proximity to MODIS fire radiative power, demonstrating that pyrogenic emissions can be clearly identified in the OMI CHOCHO product.

  6. Retrieval interval mapping, a tool to optimize the spectral retrieval range in differential optical absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Vogel, L.; Sihler, H.; Lampel, J.; Wagner, T.; Platt, U.

    2012-06-01

    Remote sensing via differential optical absorption spectroscopy (DOAS) has become a standard technique to identify and quantify trace gases in the atmosphere. The technique is applied in a variety of configurations, commonly classified into active and passive instruments using artificial and natural light sources, respectively. Platforms range from ground based to satellite instruments and trace-gases are studied in all kinds of different environments. Due to the wide range of measurement conditions, atmospheric compositions and instruments used, a specific challenge of a DOAS retrieval is to optimize the parameters for each specific case and particular trace gas of interest. This becomes especially important when measuring close to the detection limit. A well chosen evaluation wavelength range is crucial to the DOAS technique. It should encompass strong absorption bands of the trace gas of interest in order to maximize the sensitivity of the retrieval, while at the same time minimizing absorption structures of other trace gases and thus potential interferences. Also, instrumental limitations and wavelength depending sources of errors (e.g. insufficient corrections for the Ring effect and cross correlations between trace gas cross sections) need to be taken into account. Most often, not all of these requirements can be fulfilled simultaneously and a compromise needs to be found depending on the conditions at hand. Although for many trace gases the overall dependence of common DOAS retrieval on the evaluation wavelength interval is known, a systematic approach to find the optimal retrieval wavelength range and qualitative assessment is missing. Here we present a novel tool to determine the optimal evaluation wavelength range. It is based on mapping retrieved values in the retrieval wavelength space and thus visualize the consequence of different choices of retrieval spectral ranges, e.g. caused by slightly erroneous absorption cross sections, cross correlations and

  7. Information Retrieval Systems and Learning.

    ERIC Educational Resources Information Center

    Locatis, Craig

    1989-01-01

    Discusses instructional systems and information retrieval systems and highlights the growing role of retrieval systems in learning. Topics discussed include cognitive psychology; degree of learner control; interaction with the systems; technological trends, including storage capacity, integrated media, and interlinked systems; hypermedia; and…

  8. A Computerized Reference Retrieval System.

    ERIC Educational Resources Information Center

    Harline, N. La Var

    An automated retrieval system for reference works was constructed as a prototype in order to illustrate the capabilities and potentialities of future retrieval systems. More than 170 biographical works were indexed and stored in a computer disk to form a biographical data base, and a computer program was written to match patron queries. Consistent…

  9. Document Retrieval: A Structural Approach.

    ERIC Educational Resources Information Center

    Lu, Xin

    1990-01-01

    Describes the development of a structural model of document retrieval based on lexical-semantic relationships between index terms. An algorithm that uses tree-to-tree distance to measure structural closeness between a document and a query statement is explained, and the proposed model is compared to a vector retrieval model. (18 references) (LRW)

  10. NASA develops teleoperator retrieval system

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The teleoperator retrieval system vehicle was designed to reboost and/or deorbit the Skylab; however, usefulness in survey, stabilization, retrieval and delivery was examined. Thrusters, designed for cold gas propulsion, were adapted to hydrazine propulsion. Design specifications and cost analysis are given.

  11. Detecting Mood-Dependent Retrieval.

    ERIC Educational Resources Information Center

    Mayer, John D.; Bower, Gordon H.

    The mood-dependent retrieval hypothesis states that mood will enhance recall by acting as a recall cue if the stimuli have been learned initially in the same mood. Material learned in a happy mood will be best recalled when the person returns to a happy mood; the same holds for a sad mood. Mood-dependent retrieval effect has been regulary…

  12. Topology of Document Retrieval Systems.

    ERIC Educational Resources Information Center

    Everett, Daniel M.; Cater, Steven C.

    1992-01-01

    Explains the use of a topological structure to examine the closeness between documents in retrieval systems and analyzes the topological structure of a vector-space model, a fuzzy-set model, an extended Boolean model, a probabilistic model, and a TIRS (Topological Information Retrieval System) model. Proofs for the results are appended. (17…

  13. Retrieval Effectiveness on the Web.

    ERIC Educational Resources Information Center

    Savoy, Jacques; Picard, Justin

    2001-01-01

    Discusses the role of search engines in Web usability and analyzes and evaluates the retrieval effectiveness of various indexing and searching strategies on a new Web text collection. Highlights include preprocessing techniques that might improve retrieval effectiveness; and hyperlinks as useful sources of evidence in improving retrieval…

  14. Retrieval of RTG'S in earth orbit

    SciTech Connect

    Raab, B.; Frieder, M.A.; Skrabek, A.

    1982-08-01

    Since 1961, some ten Radioisotope Thermoelectric Generators (RTG's) have been placed into a variety of spacecraft which are now in earth orbit. All of these spacecraft are in orbits with lifetimes in excess of 100 years and pose no risk. However, since most of these spacecraft are no longer being actively used, these may be subject to an active removal program to reduce the population of objects in space. Therefore, a study was undertaken to evaluate the feasibility of retrieving or disposing of spacecraft with RTGs on board. Intervention scenarios are developed and an orbital rendezvous vehicle is conceptualized. The costs of RTG retrieval are derived and compared to the costs of RTG disposal, i.e., boost to a higher, multi-millenium-lifetime orbit, and are found to be not significantly different.

  15. Tanks Focus Area retrieval process development and enhancements FY96 technology development summary report

    SciTech Connect

    Rinker, M.W.; Bamberger, J.A.; Hatchell, B.K.

    1996-09-01

    The Retrieval Process Development and Enhancements (RPD&E) activities are part of the Retrieval and Closure Program of the U.S. Department of Energy (DOE) EM-50 Tanks Focus Area. The purposes of RPD&E are to understand retrieval processes, including emerging and existing technologies, and to gather data on those processes, so that end users have the requisite technical basis to make retrieval decisions. Work has been initiated to support the need for multiple retrieval technologies across the DOE complex. Technologies addressed during FY96 focused on enhancements to sluicing, borehole mining, confined sluicing retrieval end effectors, the lightweight scarifier, and pulsed air mixing. Furthermore, a decision tool and database have been initiated to link retrieval processes with tank closure to assist end users in making retrieval decisions.

  16. Developmental differences in hippocampal and cortical contributions to episodic retrieval.

    PubMed

    Demaster, Dana M; Ghetti, Simona

    2013-06-01

    Episodic memory, or the ability to form and retrieve conscious memories about specific past events, improves during childhood. Previous adult neuroimaging results indicate a central role of the hippocampus in episodic retrieval, but it is not clear whether the contribution of the hippocampus changes during development. Traditionally, developmental improvements in episodic retrieval have been thought to depend on strategic processes mediated by the prefrontal cortex (PFC), a region that is considered to have a protracted course of development relative to the hippocampus. The primary goal of the present study was to test the hypothesis that the development of episodic retrieval is also associated with changes in hippocampal function. Children ages 8- to 11-years-old and adults ages 18-25 (N = 41) encoded black and white line drawings surrounded by either a green or red border. Functional magnetic resonance imaging (fMRI) data were acquired while participants attempted to recall which colour was originally paired with each drawing. Correct recall of item-colour pairings indicated successful episodic retrieval. Activity in the anterior hippocampus, but not in the posterior hippocampus, was associated with episodic retrieval in adults, whereas activity in the posterior, but not in the anterior hippocampus, was associated with episodic retrieval in children. Developmental differences were also found in regions in anterior lateral PFC and posterior parietal cortex. Overall, these results support the view that the development of episodic memory is supported by functional changes in the hippocampus as well as in other critical cortical regions. PMID:22981810

  17. Classification Aided Analysis of Oscillatory Signatures in Controlled Retrieval

    PubMed Central

    Ketz, Nicholas; O'Reilly, Randal C.; Curran, Tim

    2013-01-01

    Control processes are critical for both facilitating and suppressing memory retrieval, but these processes are not well understood. The current work, inspired by a similar fMRI design (Detre et al., in press), used a modified Think/No-Think(TNT) paradigm to investigate the neural signatures of volition over enhancing and suppressing memory retrieval. Previous studies have shown memory enhancement when well-learned stimulus pairs are restudied in cued recall (“Recall or think of studied pair item”), and degradation when restudied with cued suppression (“Avoid thinking of studied pair item”). We used category-based (faces vs. scenes) multivariate classification of electroencephalography signals to determine if individual target items were successfully retrieved or suppressed. A logistic regression based on classifier output determined that retrieval activation during the cued recall/suppression period was a predictor for subsequent memory. Labeling trials with this internal measure, as opposed to their nominal Think vs. No-Think condition, revealed the classic TNT pattern of enhanced memory for successful cued-retrieval and degraded memory for cued-suppression. This classification process enabled a more selective investigation into the time-frequency signatures of control over retrieval. Comparing controlled retrieval vs. controlled suppression, results showed more prominent Theta oscillations (3 to 8 Hz) in controlled retrieval. Beta oscillations (12 to 30 Hz) were involved in high levels of both controlled retrieval and suppression, suggesting it may have a more general control-related role. These results suggest unique roles for these frequency bands in retrieval processes. PMID:23845425

  18. Web Mining for Web Image Retrieval.

    ERIC Educational Resources Information Center

    Chen, Zheng; Wenyin, Liu; Zhang, Feng; Li, Mingjing; Zhang, Hongjiang

    2001-01-01

    Presents a prototype system for image retrieval from the Internet using Web mining. Discusses the architecture of the Web image retrieval prototype; document space modeling; user log mining; and image retrieval experiments to evaluate the proposed system. (AEF)

  19. Antigen Retrieval Immunohistochemistry

    PubMed Central

    Shi, Shan-Rong; Shi, Yan; Taylor, Clive R.

    2011-01-01

    As a review for the 20th anniversary of publishing the antigen retrieval (AR) technique in this journal, the authors intend briefly to summarize developments in AR-immunohistochemistry (IHC)–based research and diagnostics, with particular emphasis on current challenges and future research directions. Over the past 20 years, the efforts of many different investigators have coalesced in extending the AR approach to all areas of anatomic pathology diagnosis and research and further have led to AR-based protein extraction techniques and tissue-based proteomics. As a result, formalin-fixed paraffin-embedded (FFPE) archival tissue collections are now seen as a literal treasure of materials for clinical and translational research to an extent unimaginable just two decades ago. Further research in AR-IHC is likely to focus on tissue proteomics, developing a more efficient protocol for protein extraction from FFPE tissue based on the AR principle, and combining the proteomics approach with AR-IHC to establish a practical, sophisticated platform for identifying and using biomarkers in personalized medicine. PMID:21339172

  20. Solid rocket booster retrieval operations

    NASA Technical Reports Server (NTRS)

    Rasmussen, A. M.

    1985-01-01

    Solid Rocket Booster Retrieval operations are discussed in detail. The recovery of expended boosters and associated hardware without damage attributable to retrieval procedures is the main goal. The retrieval force consists tof ship's personnel and retrieval team members, each of whom has been trained and is highly skilled in multi-faceted operations. The retrieval force is equipped with two specially-built, highly maneuverable ships outfitted with parachute reels, retrieval cranes, towing winches, large volume-low pressure air compressors, SCUBA diving gear, inflatable boats with outboard motors and diver-operated SRB dewatering devices. The two ships are deployed in sufficient time to conduct an electronic and visual search of the impact area prior to launch. Upon search completeion, each ship takes station a safe distance from the predetermined impact point initiating both visual and electronic search in the direction of flight path, ensuring SRB acquisition at splashdown. When safe, the ships enter the impact area and commence recovery of all floating flight hardware which is subsequently returned to the Disassembly Facility for refurbishment and reuse. Retrieval techniques have evolved in parallel with equipment and flight hardware configuration changes. Additional changes have been initiated to improve personnel safety.

  1. Interactive Exploration for Image Retrieval

    NASA Astrophysics Data System (ADS)

    Cord, Matthieu; Philipp-Foliguet, Sylvie; Gosselin, Philippe-Henri; Fournier, Jérôme

    2005-12-01

    We present a new version of our content-based image retrieval system RETIN. It is based on adaptive quantization of the color space, together with new features aiming at representing the spatial relationship between colors. Color analysis is also extended to texture. Using these powerful indexes, an original interactive retrieval strategy is introduced. The process is based on two steps for handling the retrieval of very large image categories. First, a controlled exploration method of the database is presented. Second, a relevance feedback method based on statistical learning is proposed. All the steps are evaluated by experiments on a generalist database.

  2. Information retrieval at the millenium.

    PubMed Central

    Hersh, W.

    1998-01-01

    Information retrieval systems were among the first medical informatics applications, yet their use has changed substantially in this decade with the growth of end-user computers and the Internet. While early challenges revolved around how to increase the amount of information available in electronic form, more recent challenges center on how to manage the growing volume. Traditional information retrieval issues--such as how to organize and index information to make it more retrievable as well as how to evaluate the effectiveness of systems--are still as pertinent as ever. PMID:9929180

  3. System For Retrieving Reusable Software

    NASA Technical Reports Server (NTRS)

    Van Warren, Lloyd; Beckman, Brian C.

    1993-01-01

    Encyclopedia of Software Components (ESC) is information-retrieval system of computer hardware and software providing access to generic reusable software tools and parts. Core of ESC is central tool base, which is repository of reusable software. It receives queries and submissions from user through local browser subsystem and receives authorized updates from maintenance subsystem. Sends retrievals to local browser subsystem and user's submissions to maintenance subsystem. Future versions will provide for advanced media, including voice and video, and will link system to database-management system. Programmers will not only retrieve software, but also modify, execute, and cross-link with other software.

  4. Combination of visual and textual similarity retrieval from medical documents.

    PubMed

    Eggel, Ivan; Müller, Henning

    2009-01-01

    Medical visual information retrieval has been an active research area over the past ten years as an increasing amount of images are produced digitally and have become available in patient records, scientific literature, and other medical documents. Most visual retrieval systems concentrate on images only, but it has become apparent that the retrieval of similar images alone is of limited interest, and rather the retrieval of similar documents is an important domain. Most medical institutions as well as the World Health Organization (WHO) produce many complex documents. Searching them, including a visual search, can help finding important information and also facilitates the reuse of document content and images. The work described in this paper is based on a proposal of the WHO that produces large amounts of documents from studies but also for training. The majority of these documents are in complex formats such as PDF, Microsoft Word, Excel, or PowerPoint. Goal is to create an information retrieval system that allows easy addition of documents and search by keywords and visual content. For text retrieval, Lucene is used and for image retrieval the GNU Image Finding Tool (GIFT). A Web 2.0 interface allows for an easy upload as well as simple searching. PMID:19745431

  5. Image retrieval for information systems

    NASA Astrophysics Data System (ADS)

    Hermes, Thorsten; Klauck, Christoph; Kreyss, Jutta; Zhang, J.

    1995-03-01

    In order to retrieve a set of intended images from a huge image archive, human beings think of special contents with respect to the searched scene, like a countryside or a technical drawing. Therefore, in general it is harder to retrieve images by using a syntactical feature- based language than a language which offers the selection of examples concerning color, texture, and contour in combination with natural language concepts. This motivation leads to a content-based image analysis and goes on to a content-based storage and retrieval of images. Furthermore, it is unreasonable for any human being to make the content description for thousands of images manually. From this point of view, the project IRIS (image retrieval for information systems) combines well-known methods and techniques in computer vision and AI in a new way to generate content descriptions of images in a textual form automatically. IRIS retrieves the images by means of text retrieval realized by the SearchManager/6000. The textual description is generated by four sub-steps: feature extraction like colors, textures, and contours, segmentation, and interpretation of part-whole relations. The system is implemented on IBM RS/6000 using AIX. It has already been tested with 350 images.

  6. Quinoline-2-carboimine copper complex immobilized on amine functionalized silica coated magnetite nanoparticles: a novel and magnetically retrievable catalyst for the synthesis of carbamates via C-H activation of formamides.

    PubMed

    Sharma, R K; Dutta, Sriparna; Sharma, Shivani

    2015-01-21

    In the present study, we report the synthesis of a highly efficient and magnetically retrievable catalytic system (Cu-2QC@Am-SiO2@Fe3O4) through the covalent immobilization of quinoline-2-carboxaldehyde (2QC) on an amine functionalized silica coated ferrite nanosupport followed by metallation with copper acetate. The structure of the organic-inorganic hybrid nanomaterial has been confirmed using various physicochemical techniques such as Powder X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray Spectroscopy (EDS), Energy Dispersive X-Ray Fluorescence Spectroscopy (ED-XRF), Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma Spectroscopy (ICP) and Vibrating Sample Magnetometry (VSM). The resulting nanocatalyst exhibits a remarkable catalytic efficacy in the synthesis of industrially and pharmaceutically significant carbamates via the C-H activation of formamides under solvent free conditions. The most important attribute of the present methodology is that the catalyst can be recovered simply through an external magnetic force and reused several times without any significant deterioration in its activity. Furthermore, the heterogeneity test has been carried out in order to ensure the intrinsic stability of the nanostructured catalyst. The activity of the Cu-2QC@Am-SiO2@Fe3O4 nanocatalyst has been found to be far more superior in comparison with the literature precedents in terms of the product yield, cost and reusability of the catalyst. Besides, ambient reaction conditions, simple workup procedure, wide substrate scope and cost effectiveness are some of the other outstanding features of this protocol that make it economical and sustainable. PMID:25417959

  7. Quantitative Assessment of Image Retrieval Effectiveness.

    ERIC Educational Resources Information Center

    Smith, John R.

    2001-01-01

    Examines the problems of developing a framework and testbed for quantitative assessment of image retrieval effectiveness. To better harness the extensive research on content-based retrieval and improve capabilities of image retrieval systems, this article advocates the establishment of common image retrieval testbeds consisting of standardized…

  8. An improved glyoxal retrieval from OMI measurements

    NASA Astrophysics Data System (ADS)

    Alvarado, L. M. A.; Richter, A.; Vrekoussis, M.; Wittrock, F.; Hilboll, A.; Schreier, S. F.; Burrows, J. P.

    2014-12-01

    Satellite observations from the SCIAMACHY, GOME-2 and OMI spectrometers have been used to retrieve atmospheric columns of glyoxal (CHOCHO) with the DOAS method. High CHOCHO levels were found over regions with large biogenic and pyrogenic emissions, and hot-spots have been identified over areas of anthropogenic activities. This study focuses on the development of an improved retrieval for CHOCHO from measurements by the OMI instrument. From sensitivity tests, a fitting window and a polynomial degree are determined. Two different approaches to reduce the interference of liquid water absorption over oceanic regions are evaluated, achieving significant reduction of the number of negative columns over clear water regions. The impact of using different absorption cross-sections for water vapour is evaluated and only small differences are found. Finally, a high-temperature (boundary layer ambient: 294 K) absorption cross-section of nitrogen dioxide (NO2) is introduced in the DOAS retrieval to account for potential interferences of NO2 over regions with large anthropogenic emissions, leading to improved fit quality over these areas. A comparison with vertical CHOCHO columns retrieved from GOME-2 and SCIAMACHY measurements over continental regions is performed, showing overall good consistency. However, SCIAMACHY CHOCHO columns are systematically higher than those obtained from the other instruments. Using the new OMI CHOCHO data set, the link between fires and glyoxal columns is investigated for two selected regions in Africa. In addition, mapped averages are computed for a fire event in Russia between mid-July and mid-August 2010. In both cases, enhanced CHOCHO levels are found in close spatial and temporal proximity to elevated levels of MODIS fire radiative power, demonstrating that pyrogenic emissions can be clearly identified in the new OMI CHOCHO product.

  9. EM-50 Tanks Focus Area retrieval process development and enhancements. FY97 technology development summary report

    SciTech Connect

    Rinker, M.W.; Bamberger, J.A.; Alberts, D.G.

    1997-09-01

    The Retrieval Process Development and Enhancements (RPD and E) activities are part of the US Department of Energy (DOE) EM-50 Tanks Focus Area, Retrieval and Closure program. The purpose of RPD and E is to understand retrieval processes, including emerging and existing technologies, and to gather data on these processes, so that end users have requisite technical bases to make retrieval decisions. Technologies addressed during FY97 include enhancements to sluicing, the use of pulsed air to assist mixing, mixer pumps, innovative mixing techniques, confined sluicing retrieval end effectors, borehole mining, light weight scarification, and testing of Russian-developed retrieval equipment. Furthermore, the Retrieval Analysis Tool was initiated to link retrieval processes with tank waste farms and tank geometric to assist end users by providing a consolidation of data and technical information that can be easily assessed. The main technical accomplishments are summarized under the following headings: Oak Ridge site-gunite and associated tanks treatability study; pulsed air mixing; Oak Ridge site-Old Hydrofracture Facility; hydraulic testbed relocation; cooling coil cleaning end effector; light weight scarifier; innovative tank mixing; advanced design mixer pump; enhanced sluicing; Russian retrieval equipment testing; retrieval data analysis and correlation; simulant development; and retrieval analysis tool (RAT).

  10. Determiner Primes as Facilitators of Lexical Retrieval in English

    ERIC Educational Resources Information Center

    Gregory, Emma; Varley, Rosemary; Herbert, Ruth

    2012-01-01

    Gender priming studies have demonstrated facilitation of noun production following pre-activation of a target noun's grammatical gender. Findings provide support for models in which syntactic information relating to words is stored within the lexicon and activated during lexical retrieval. Priming effects are observed in the context of determiner…

  11. Retrieval for color artistry concepts.

    PubMed

    Lay, Jose A; Guan, Ling

    2004-03-01

    This paper presents a work on the retrieval of artworks for color artistry concepts. First we affirm the view that the Query-by-Example paradigm fundamental to the current content-based retrieval systems is able to extend only limited usefulness. We then propose a concept-based retrieval engine based on the generative grammar of elemental concepts methodology. In the latter, the language by which color artistry concepts are communicated in artworks is used to operate semantic searches. The color artistry language is explicated into elemental concepts and the associated generative grammar. The elemental concepts are used to index the artworks, while the generative grammar is used to facilitate post-coordinate expression of color artistry concept queries by using the elemental concepts. PMID:15376925

  12. Multimedia Information Retrieval Literature Review

    SciTech Connect

    Wong, Pak C.; Bohn, Shawn J.; Payne, Deborah A.

    2010-10-12

    This survey paper highlights some of the recent, influential work in multimedia information retrieval (MIR). MIR is a branch area of multimedia (MM). The young and fast-growing area has received strong industrial and academic support in the United States and around the world (see Section 7 for a list of major conferences and journals of the community). The term "information retrieval" may be misleading to those with different computer science or information technology backgrounds. As shown in our discussion later, it indeed includes topics from user interaction, data analytics, machine learning, feature extraction, information visualization, and more.

  13. Information retrieval for patient care.

    PubMed Central

    Gardner, M.

    1997-01-01

    Doctors need clinical information during most consultations with patients, and much of this need could be satisfied by material from online sources. Advances in data communication technologies mean that multimedia information can be transported rapidly to various clinical care locations. However, selecting the few items of information likely to be useful in a particular clinical situation from the mass of information available is a major problem. Current information retrieval systems are designed primarily for use in research rather than clinical care. The design, implementation, and critical evaluation of new information retrieval systems for clinical care should be guided by knowledgeable clinical users. PMID:9099122

  14. Publication search and retrieval system

    USGS Publications Warehouse

    Winget, Elizabeth A.

    1981-01-01

    The publication search and retrieval system of the Branch of Atlantic-Gulf of Mexico Geology, U.S. Geological Survey, Woods Hole, Mass., is a procedure for listing and describing branch-sponsored publications. It is designed for maintenance and retrieval by those having limited knowledge of computer languages and programs. Because this branch currently utilizes the Hewlett-Packard HP-1000 computer with RTE-IVB operating system, database entry and maintenance is performed in accordance with the TE-IVB Terminal User’s Reference Manual (Hewlett-Packard Company, 1980) and within the constraints of GRASP (Bowen and Botbol, 1975) and WOLF (Evenden, 1978).

  15. Text Passage Retrieval Based on Colon Classification: Retrieval Performance.

    ERIC Educational Resources Information Center

    Shepherd, Michael A.

    1981-01-01

    Reports the results of experiments using colon classification for the analysis, representation, and retrieval of primary information from the full text of documents. Recall, precision, and search length measures indicate colon classification did not perform significantly better than Boolean or simple word occurrence systems. Thirteen references…

  16. AIR PERMIT COMPLIANCE FOR WASTE RETRIEVAL OEPRATIONS INVOLVING MULTI-UNIT OPERATIONS

    SciTech Connect

    SIMMONS FM

    2007-11-05

    Since 1970, approximately 38,000 suspect-transuranic and transuranic waste containers have been placed in retrievable storage on the Hanford Site in the 200 Areas burial grounds. Hanford's Waste Retrieval Project is retrieving these buried containers and processing them for safe storage and disposition. Container retrieval activities require an air emissions permit to account for potential emissions of radionuclides. The air permit covers the excavation activities as well as activities associated with assaying containers and installing filters in the retrieved transuranic containers lacking proper venting devices. Fluor Hanford, Inc. is required to track radioactive emissions resulting from the retrieval activities. Air, soil, and debris media contribute to the emissions and enabling assumptions allow for calculation of emissions. Each of these activities is limited to an allowed annual emission (per calendar year) and .contributes to the overall total emissions allowed for waste retrieval operations. Tracking these emissions is required to ensure a permit exceedance does not occur. A tracking tool was developed to calculate potential emissions in real time sense. Logic evaluations are established within the tracking system to compare real time data against license limits to ensure values are not exceeded for either an individual activity or the total limit. Data input are based on field survey and workplace air monitoring activities. This tracking tool is used monthly and quarterly to verify compliance to the license limits. Use of this tool has allowed Fluor Hanford, Inc. to successfully retrieve a significant number of containers in a safe manner without any exceedance of emission limits.

  17. Photopolarimetric Retrievals of Snow Properties

    NASA Technical Reports Server (NTRS)

    Ottaviani, M.; van Diedenhoven, B.; Cairns, B.

    2015-01-01

    Polarimetric observations of snow surfaces, obtained in the 410-2264 nm range with the Research Scanning Polarimeter onboard the NASA ER-2 high-altitude aircraft, are analyzed and presented. These novel measurements are of interest to the remote sensing community because the overwhelming brightness of snow plagues aerosol and cloud retrievals based on airborne and spaceborne total reflection measurements. The spectral signatures of the polarized reflectance of snow are therefore worthwhile investigating in order to provide guidance for the adaptation of algorithms currently employed for the retrieval of aerosol properties over soil and vegetated surfaces. At the same time, the increased information content of polarimetric measurements allows for a meaningful characterization of the snow medium. In our case, the grains are modeled as hexagonal prisms of variable aspect ratios and microscale roughness, yielding retrievals of the grains' scattering asymmetry parameter, shape and size. The results agree with our previous findings based on a more limited data set, with the majority of retrievals leading to moderately rough crystals of extreme aspect ratios, for each scene corresponding to a single value of the asymmetry parameter.

  18. Hypermedia and Free Text Retrieval.

    ERIC Educational Resources Information Center

    Dunlop, Mark D.; van Rijsbergen, C. J.

    1993-01-01

    Discusses access to nontextual documents in large multimedia document bases. A hybrid information retrieval model, using queries in a hypertext environment for location of browsing areas, is presented; and two experiments using cluster-based descriptions of content are reported. (23 references) (EA)

  19. The Intrex Retrieval System Software.

    ERIC Educational Resources Information Center

    Hurlburt, Charles E.; And Others

    The report describes the general structure of the Intrex Retrieval Systems and each of the component subroutines. The report is not an introduction to Intrex. In addition to a general description, the report covers the following topics: (1) system architecture, (2) software details, (3) command control logic, (4) list manipulation logic, (5)…

  20. Photopolarimetric retrievals of snow properties

    NASA Astrophysics Data System (ADS)

    Ottaviani, M.; van Diedenhoven, B.; Cairns, B.

    2015-10-01

    Polarimetric observations of snow surfaces, obtained in the 410-2264 nm range with the Research Scanning Polarimeter onboard the NASA ER-2 high-altitude aircraft, are analyzed and presented. These novel measurements are of interest to the remote sensing community because the overwhelming brightness of snow plagues aerosol and cloud retrievals based on airborne and spaceborne total reflection measurements. The spectral signatures of the polarized reflectance of snow are therefore worthwhile investigating in order to provide guidance for the adaptation of algorithms currently employed for the retrieval of aerosol properties over soil and vegetated surfaces. At the same time, the increased information content of polarimetric measurements allows for a meaningful characterization of the snow medium. In our case, the grains are modeled as hexagonal prisms of variable aspect ratios and microscale roughness, yielding retrievals of the grains' scattering asymmetry parameter, shape and size. The results agree with our previous findings based on a more limited data set, with the majority of retrievals leading to moderately rough crystals of extreme aspect ratios, for each scene corresponding to a single value of the asymmetry parameter.

  1. Photopolarimetric retrievals of snow properties

    NASA Astrophysics Data System (ADS)

    Ottaviani, M.; van Diedenhoven, B.; Cairns, B.

    2015-05-01

    Polarimetric observations of snow surfaces, obtained in the 410-2264 nm range with the Research Scanning Polarimeter onboard the NASA ER-2 high-altitude aircraft, are analyzed and presented. These novel measurements are of interest to the remote sensing community because the overwhelming brightness of snow plagues aerosol and cloud retrievals based on air- and space-borne total reflection measurements. The spectral signatures of the polarized reflectance of snow are therefore worthwhile investigating in order to provide guidance for the adaptation of algorithms currently employed for the retrieval of aerosol properties over soil and vegetated surfaces. At the same time, the increased information content of polarimetric measurements allows for a meaningful characterization of the snow medium. In our case, the grains are modeled as hexagonal prisms of variable aspect ratios and microscale roughness, yielding retrievals of the grains' scattering asymmetry parameter, shape and size. The results agree with our previous findings based on a more limited dataset, with the majority of retrievals leading to moderately rough crystals of extreme aspect ratios, for each scene corresponding to a single value of the asymmetry parameter.

  2. Information Retrieval Systems for Microcomputers.

    ERIC Educational Resources Information Center

    Seiden, Peggy; Kibbey, Mark

    1985-01-01

    Discusses the characteristics of information retrieval software and examines several capabilities of two systems, SIRE and ZyINDEX--creating a database, indexing the database, maintaining the database, and searching the database. Each system's strengths and weaknesses in bibliographic record and full text applications are analyzed. A glossary is…

  3. An Introduction to Information Retrieval.

    ERIC Educational Resources Information Center

    International Business Machines Corp., White Plains, NY. Data Processing Div.

    The ways in which digital computers can be used in information storage and retrieval are presented in the language of the nonspecialist. Indexing methods, file organization, and search strategies are discussed and a brief bibliography containing 30 IBM publications is given. The manual is intended as a first reader for those interested in the…

  4. INFORMATION RETRIEVAL EXPERIMENT. FINAL REPORT.

    ERIC Educational Resources Information Center

    SELYE, HANS

    THIS REPORT IS A BRIEF REVIEW OF RESULTS OF AN EXPERIMENT TO DETERMINE THE INFORMATION RETRIEVAL EFFICIENCY OF A MANUAL SPECIALIZED INFORMATION SYSTEM BASED ON 700,000 DOCUMENTS IN THE FIELDS OF ENDOCRINOLOGY, STRESS, MAST CELLS, AND ANAPHYLACTOID REACTIONS. THE SYSTEM RECEIVES 30,000 PUBLICATIONS ANNUALLY. DETAILED INFORMATION IS REPRESENTED BY…

  5. Artificial Intelligence and Information Retrieval.

    ERIC Educational Resources Information Center

    Teodorescu, Ioana

    1987-01-01

    Compares artificial intelligence and information retrieval paradigms for natural language understanding, reviews progress to date, and outlines the applicability of artificial intelligence to question answering systems. A list of principal artificial intelligence software for database front end systems is appended. (CLB)

  6. Semantic Tools in Information Retrieval.

    ERIC Educational Resources Information Center

    Rubinoff, Morris; Stone, Don C.

    This report discusses the problem of the meansings of words used in information retrieval systems, and shows how semantic tools can aid in the communication which takes place between indexers and searchers via index terms. After treating the differing use of semantic tools in different types of systems, two tools (classification tables and…

  7. Cross-Language Information Retrieval.

    ERIC Educational Resources Information Center

    Oard, Douglas W.; Diekema, Anne R.

    1998-01-01

    Reviews research and practice in cross-language information retrieval (CLIR) that seeks to support the process of finding documents written in one natural language with automated systems that can accept queries expressed in other languages. Addresses user needs, document preprocessing, query formulation, matching strategies, sources of translation…

  8. Formaldehyde OMI operational retrieval upgrades

    NASA Astrophysics Data System (ADS)

    Gonzalez Abad, G.; Chance, K.; Liu, X.

    2013-05-01

    Total column of formaldehyde (HCHO), a proxy for biogenic emissions, can be observed from satellites using the ultraviolet region of the spectrum. The operational HCHO retrievals from the Ozone Monitoring Instrument (OMI) on board the AURA satellite, part of NASA's A-train constellation of Earth Observing satellites, are described. The operational retrieval, based on a basic optical absorption spectroscopy (BOAS) algorithm, has been affected by the degradation of the instrument especially from 2008 onwards. The most significant problems are the unrealistic increasing high background concentrations of HCHO retrieved from OMI and the row anomaly. An upgrade for the original operational algorithm is therefore needed to ensure its trend quality and to account for these difficulties. The strategies implemented to deal with the instrumental degradation are presented here. Air mass factors (AMFs) in the current fitting window show significant wavelength dependence. Fitting uncertainties can potentially be improved by including shorter wavelengths as long as the AMFs wavelength dependence is taken into account. As part of these improvements a look-up table of wavelength-dependent AMFs have been calculated. Using this new table it is possible to retrieve the HCHO total column directly, weighting the HCHO cross sections with the wavelength-dependent AMFs. Additionally, the pixels affected by the row anomaly are now flagged in the level 2 data generated with the upgraded algorithm.

  9. The Ecosystem of Information Retrieval

    ERIC Educational Resources Information Center

    Rodriguez-Munoz, Jose-Vicente; Martinez-Mendez, Francisco-Javier; Pastor-Sanchez, Juan-Antonio

    2012-01-01

    Introduction: This paper presents an initial proposal for a formal framework that, by studying the metric variables involved in information retrieval, can establish the sequence of events involved and how to perform it. Method: A systematic approach from the equations of Shannon and Weaver to establish the decidability of information retrieval…

  10. Information Retrieval in the Classroom.

    ERIC Educational Resources Information Center

    Oley, Elizabeth

    1989-01-01

    Explores aspects of information retrieval skills such as end user training, indexing, controlled vocabulary systems, search protocol, boolean logic, problem analysis, and decision making. Suggests techniques for classroom instruction using simulations of online databases, CD-ROMs, and DIALOG's classroom instruction program. Describes several…

  11. Satellite Retrieval of Aerosol Properties

    NASA Astrophysics Data System (ADS)

    de Leeuw, G.; Robles Gonzalez, C.; Kusmierczyk-Michulec, J.; Decae, R.

    SATELLITE RETRIEVAL of AEROSOL PROPERTIES G. de Leeuw, C. Robles Gonzalez, J. Kusmierczyk-Michulec and R. Decae TNO Physics and Electronics Laboratory, The Hague, The Netherlands; deleeuw@fel.tno.nl Methods to retrieve aerosol properties over land and over sea were explored. The dual view offered by the ATSR-2 aboard ERS-2 was used by Veefkind et al., 1998. The retrieved AOD (aerosol optical depth) values compare favourably with collocated sun photometer measurements, with an accuracy of 0.06 +/- 0.05 in AOD. An algorithm developed for GOME on ERS-2 takes advantage of the low surface reflection in the UV (Veefkind et al., 2000). AOD values retrieved from ATSR-2 and GOME data over western Europe are consistent. The results were used to produce a map of mean AOD values over Europe for one month (Robles-Gonzalez et al., 2000). The ATSR-2 is al- gorithm is now extended with other aerosol types with the aim to apply it over the In- dian Ocean. A new algorithm is being developed for the Ozone Monitoring Instrument (OMI) to be launched in 2003 on the NASA EOS-AURA satellite. It is expected that, based on the different scattering and absorption properties of various aerosol types, five major aerosol classes can be distinguished. The experience with the retrieval of aerosol properties by using several wavelength bands is used to develop an algorithm for Sciamachy to retrieve aerosol properties both over land and over the ocean which takes advantage of the wavelengths from the UV to the IR. The variation of the AOD with wavelength is described by the Angstrom parameter. The AOD and the Angstrom parameter together yield information on the aerosol size distribution, integrated over the column. Analysis of sunphotometer data indicates a relation between the Angstrom parameter and the mass ratio of certain aerosols (black carbon, organic carbon and sea salt) to the total particulate matter. This relation has been further explored and was applied to satellite data over land to

  12. Comparing the quality of accessing medical literature using content-based visual and textual information retrieval

    NASA Astrophysics Data System (ADS)

    Müller, Henning; Kalpathy-Cramer, Jayashree; Kahn, Charles E., Jr.; Hersh, William

    2009-02-01

    Content-based visual information (or image) retrieval (CBIR) has been an extremely active research domain within medical imaging over the past ten years, with the goal of improving the management of visual medical information. Many technical solutions have been proposed, and application scenarios for image retrieval as well as image classification have been set up. However, in contrast to medical information retrieval using textual methods, visual retrieval has only rarely been applied in clinical practice. This is despite the large amount and variety of visual information produced in hospitals every day. This information overload imposes a significant burden upon clinicians, and CBIR technologies have the potential to help the situation. However, in order for CBIR to become an accepted clinical tool, it must demonstrate a higher level of technical maturity than it has to date. Since 2004, the ImageCLEF benchmark has included a task for the comparison of visual information retrieval algorithms for medical applications. In 2005, a task for medical image classification was introduced and both tasks have been run successfully for the past four years. These benchmarks allow an annual comparison of visual retrieval techniques based on the same data sets and the same query tasks, enabling the meaningful comparison of various retrieval techniques. The datasets used from 2004-2007 contained images and annotations from medical teaching files. In 2008, however, the dataset used was made up of 67,000 images (along with their associated figure captions and the full text of their corresponding articles) from two Radiological Society of North America (RSNA) scientific journals. This article describes the results of the medical image retrieval task of the ImageCLEF 2008 evaluation campaign. We compare the retrieval results of both visual and textual information retrieval systems from 15 research groups on the aforementioned data set. The results show clearly that, currently

  13. Functions and requirements for 105-KE Basin sludge retrieval and packaging

    SciTech Connect

    Feigenbutz, L.V.

    1994-12-16

    Sludge, and the clouding due to sludge, interferes with basin operation and maintenance activities. This document defines the overall functions and requirements for sludge retrieval and packaging activities to be performed in the 105-KE Basin.

  14. Context Effects and Retrieval in Recognition Memory

    ERIC Educational Resources Information Center

    Paul, Lawrence M.; And Others

    1975-01-01

    Describes an experiment designed to test predictions derived from a model of recognition memory that assumes no retrieval processes. It is argued that context effects do not necessarily imply retrieval processes in recognition. (Author/AM)

  15. Brewer Umkehr ozone profile retrievals

    NASA Astrophysics Data System (ADS)

    Petropavlovskikh, I. V.; Disterhoft, P.; Lantz, K. O.; Bhartia, P. K.; McPeters, R. D.; Flynn, L. E.; Oltmans, S. J.; Johnson, B. J.; Stanek, M.

    2011-12-01

    The Dobson Umkehr network has been a key data set for stratospheric ozone trend calculations (WMO Ozone assessments) and has earned its place as a benchmark network for stratospheric ozone profile observations. The Umkehr data has also been used to provide a long-term reference to the merging of the satellite ozone records (MOD), estimate the seasonal influence of an 11-year solar signal in the vertical distribution of stratospheric ozone, and to assess the ability of several remote and in-situ sensing systems in capturing ozone variability. It was found that Dobson Umkehr measurement errors were often comparable to errors derived for satellite and ozone-sounding methods. The Umkehr measurements are also available from the Brewer spectrophotometers [McElroy et al., 1995]. In 2005, the Dobson Umkehr algorithm (UMK04) was modified to retrieve ozone profile data from Brewer Umkehr measurements taken at two spectral channels [Petropavlovskikh et al, 2011]. The PC version of the Brewer algorithm was developed by M. Stanek (IOC, Canada and Czech Republic Meteorological Institute) in close collaboration with I. Petropavlovskikh. It was implemented at the NEUBrew network for operational processing of Umkehr data retrieved daily for all operational sites. The most recently developed Brewer ozone retrieval algorithm (MSBU) utilizes measurements that are currently available from the operational Brewer instruments. Umkehr measurements at multiple wavelength channels (similar to the satellite BUV method) and significantly reduced range of solar zenith angle are used for the twice a day operational ozone profile retrievals. Intercomparisons against ozone climatology, sounding, satellite overpasses and Dobson ozone datasets for NOASA/Goddard, Boulder, CO and MLO, HI sites are presented in this paper. The MSBU algorithm reduces noise in the intra-annual variability of the Brewer retrieved ozone as compared to the single pair ozone retrieval. Tropospheric ozone retrievals also

  16. Tank 241-C-106 waste retrieval sluicing system process control plan

    SciTech Connect

    Carothers, K.G.

    1998-07-25

    Project W-320 has installed the Waste Retrieval Sluicing System at the 200 East Area on the Hanford Site to retrieve the sludge from single-shell tank 241-C-106 and transfer it into double-shell tank 241-AY-102. Operation of the WRSS process will resolve the high-heat safety issue for tank 241-C-106 and demonstrate a technology for the retrieval of single-shell tank wastes. This process control plan coordinates the technical operating requirements (primarily mass transfer, temperature, and flammable gas) for the sluicing operation and provides overall technical guidance for the retrieval activity.

  17. Retrieval Induces Adaptive Forgetting of Competing Memories via Cortical Pattern Suppression

    PubMed Central

    Wimber, Maria; Alink, Arjen; Charest, Ian; Kriegeskorte, Nikolaus; Anderson, Michael C.

    2015-01-01

    Remembering a past experience can, surprisingly, cause forgetting. Forgetting arises when other competing traces interfere with retrieval, and inhibitory control mechanisms are engaged to suppress the distraction they cause. This form of forgetting is considered adaptive because it reduces future interference. The impact of this proposed inhibition process on competing memories has, however, never been observed both because behavioural methods are “blind” to retrieval dynamics and because neuroimaging methods have not isolated retrieval of individual memories. Here we introduce a canonical template tracking method to quantify the activation state of individual target memories and competitors during retrieval. This method revealed that repeatedly retrieving target memories suppressed cortical patterns unique to competitors. Pattern suppression was related to engagement of prefrontal regions implicated in resolving retrieval competition, and, critically, predicted later forgetting. We thus demonstrate a cortical pattern suppression mechanism through which remembering adaptively shapes which aspects of our past remain accessible. PMID:25774450

  18. Intelligent Information Retrieval Using Rough Set Approximations.

    ERIC Educational Resources Information Center

    Srinivasan, Padmini

    1989-01-01

    Describes rough sets theory and discusses the advantages it offers for information retrieval, including the implicit inclusion of Boolean logic, term weighting, ranked retrieval output, and relevance feedback. Rough set formalism is compared to Boolean, vector, and fuzzy models of information retrieval and a small scale evaluation of rough sets is…

  19. Online Retrieval Systems Users Survey from Texas.

    ERIC Educational Resources Information Center

    White, Phillip M.

    Based on a survey of 160 Texas college and university libraries, this study reports on their access to and usage of 3 online information retrieval systems: Bibliographic Retrieval Services (BRS), Lockheed's DIALOG Information Services, and System Development Corporation's ORBIT Information Retrieval System. The study finds that 24 percent of all…

  20. EXPERIMENTAL RETRIEVAL SYSTEMS STUDIES, REPORT NUMBER 3.

    ERIC Educational Resources Information Center

    ANDERSON, RONALD R.; AND OTHERS

    CONTENTS--(1) AN ASSOCIATIVITY TECHNIQUE FOR AUTOMATICALLY OPTIMIZING RETRIEVAL RESULTS BY RONALD R. ANDERSON. AN ASSOCIATIVE TECHNIQUE BY WHICH IT IS POSSIBLE TO AUTOMATICALLY EXPAND AND NARROW THE NUMBER OF DOCUMENTS RETRIEVED AND TO RETRIEVE DOCUMENTS RELATED TO A REQUEST EVEN THOUGH THEY MAY NOT BE INDEXED BY THE EXACT TERMS OF THE REQUEST IS…

  1. Validating a Geographical Image Retrieval System.

    ERIC Educational Resources Information Center

    Zhu, Bin; Chen, Hsinchun

    2000-01-01

    Summarizes a prototype geographical image retrieval system that demonstrates how to integrate image processing and information analysis techniques to support large-scale content-based image retrieval. Describes an experiment to validate the performance of this image retrieval system against that of human subjects by examining similarity analysis…

  2. A Fuzzy Model of Document Retrieval Systems

    ERIC Educational Resources Information Center

    Tahani, Valiollah

    1976-01-01

    This paper is concerned with the organization and retrieval of records in document retrieval systems which admit of imprecision in the form of fuzziness in document characterization and retrieval rules. A mathematical model for such systems, based on the theory of fuzzy sets, is introduced. (Author)

  3. Modeling and Retrieving Images by Content.

    ERIC Educational Resources Information Center

    Gudivada, Venkat N.; Raghavan, Vijay V.

    1997-01-01

    Discusses content-based image retrieval systems that effectively utilize information from image databases, and provides a taxonomy for approaches to image retrieval. Highlights include image retrieval architecture that supports query operators; conceptual issues; and two application prototypes. (100 references) (Author/LRW)

  4. Image Indexing and Retrieval by Content.

    ERIC Educational Resources Information Center

    Cawkell, Tony

    2000-01-01

    Reviews content-based image retrieval and discusses the increase in large picture databases that are now available. Describes some of the proceedings from the Brighton (United Kingdom) conference, including the retrieval of video clips; discusses image indexing; and provides examples of image indexing and retrieval projects. (Author/LRW)

  5. The Networking of Interactive Bibliographic Retrieval Systems.

    ERIC Educational Resources Information Center

    Marcus, Richard S.; Reintjes, J. Francis

    Research in networking of heterogeneous interactive bibliographic retrieval systems is being conducted which centers on the concept of a virtual retrieval system. Such a virtual system would be created through a translating computer interface that would provide access to the different retrieval systems and data bases in a uniform and convenient…

  6. Natural Language Information Retrieval: Progress Report.

    ERIC Educational Resources Information Center

    Perez-Carballo, Jose; Strzalkowski, Tomek

    2000-01-01

    Reports on the progress of the natural language information retrieval project, a joint effort led by GE (General Electric) Research, and its evaluation at the sixth TREC (Text Retrieval Conference). Discusses stream-based information retrieval, which uses alternative methods of document indexing; advanced linguistic streams; weighting; and query…

  7. Some Mathematics of Information Storage and Retrieval.

    ERIC Educational Resources Information Center

    Sammon, John W., Jr.

    This report explains the following mathematical techniques which may be used for relating search requests to documents contained in a library: (1) Boolean Algebraic Retrieval, (2) Linear Statistical Retrieval, (3) Statistical Association Techniques for expanding a query and/or for expanding the set of retrieval documents, (4) Vector Space…

  8. W-320, waste retrieval sluicing system: Operational start up plan

    SciTech Connect

    Bevins, R.R.

    1998-07-25

    This plan details the sequence of activities and identifies the organizational roles and responsibilities to ensure a safe startup of the Waste Retrieval Sluicing System (WRSS). This start up plan identifies the activities which must be performed during the initial startup as well as the document which directs each step. This startup plan does not authorize or direct any specific field activities or authorize a change of configuration. As such, this plan does not require a USQ screening.

  9. Autobiographical Memory Performance in Alzheimer's Disease Depends on Retrieval Frequency.

    PubMed

    Müller, Stephan; Mychajliw, Christian; Reichert, Carolin; Melcher, Tobias; Leyhe, Thomas

    2016-04-18

    Alzheimer's disease (AD) is characterized by memory disturbances primarily caused by pathogenic mechanisms affecting medial temporal lobe structures. As proposed by current theories of memory formation, this decrease is mediated by the age of the acquired knowledge. However, they cannot fully explain specific patterns of retrograde amnesia in AD. In the current study we examined an alternative approach and investigated whether the extent and severity of retrograde amnesia in AD is mediated by the frequency of memory retrieval or whether it depends on the mere age of knowledge. We compared recall of autobiographical incidents from three life periods in patients with amnestic mild cognitive impairment (aMCI), patients with early dementia of Alzheimer type (eDAT), and healthy control (HC) individuals using the Autobiographical Memory Interview. Retrieval frequency was operationalized by a paired comparison analysis. In contrast to HC individuals, recall of autobiographical incidents was impaired in patients with aMCI and eDAT following Ribot's gradient, with a reduced memory loss for remote compared to more recent life events. However, there was a strong effect of retrieval frequency on memory performance with frequently retrieved incidents memorized in more detail than less frequently retrieved episodes. Remote memories were recalled more often than recent ones. These findings suggest that more frequently retrieved autobiographical memories generally become more independent of the hippocampal complex and might thus be better protected against early hippocampal damage related to AD. Hence, the extent of retrograde amnesia in AD appears mainly mediated by the frequency of memory retrieval, which could plausibly explain why cognitive activity can effectively delay the onset of memory decline in AD. PMID:27104895

  10. Covert Retrieval Practice Benefits Retention as Much as Overt Retrieval Practice

    ERIC Educational Resources Information Center

    Smith, Megan A.; Roediger, Henry L., III; Karpicke, Jeffrey D.

    2013-01-01

    Many experiments provide evidence that practicing retrieval benefits retention relative to conditions of no retrieval practice. Nearly all prior research has employed retrieval practice requiring overt responses, but a few experiments have shown that covert retrieval also produces retention advantages relative to control conditions. However,…

  11. Toward an Episodic Context Account of Retrieval-Based Learning: Dissociating Retrieval Practice and Elaboration

    ERIC Educational Resources Information Center

    Lehman, Melissa; Smith, Megan A.; Karpicke, Jeffrey D.

    2014-01-01

    We tested the predictions of 2 explanations for retrieval-based learning; while the elaborative retrieval hypothesis assumes that the retrieval of studied information promotes the generation of semantically related information, which aids in later retrieval (Carpenter, 2009), the episodic context account proposed by Karpicke, Lehman, and Aue (in…

  12. Episodic retrieval involves early and sustained effects of reactivating information from encoding.

    PubMed

    Johnson, Jeffrey D; Price, Mason H; Leiker, Emily K

    2015-02-01

    Several fMRI studies have shown a correspondence between the brain regions activated during encoding and retrieval, consistent with the view that memory retrieval involves hippocampally-mediated reinstatement of cortical activity. With the limited temporal resolution of fMRI, the precise timing of such reactivation is unclear, calling into question the functional significance of these effects. Whereas reactivation influencing retrieval should emerge with neural correlates of retrieval success, that signifying post-retrieval monitoring would trail retrieval. The present study employed EEG to provide a temporal landmark of retrieval success from which we could investigate the sub-trial time course of reactivation. Pattern-classification analyses revealed that early-onsetting reactivation differentiated the outcome of recognition-memory judgments and was associated with individual differences in behavioral accuracy, while reactivation was also evident in a sustained form later in the trial. The EEG findings suggest that, whereas prior fMRI findings could be interpreted as reflecting the contribution of reinstatement to retrieval success, they could also indicate the maintenance of episodic information in service of post-retrieval evaluation. PMID:25463451

  13. IRES: image retrieval expert system

    NASA Astrophysics Data System (ADS)

    Liu Sheng, Olivia R.; Wang, Hui-Chin; Garcia, Hong-Mei C.

    1990-08-01

    Image Retrieval Expert System (IRES), a knowledge-based system for automatic image retrieval, is being prototyped at the University of Arizona (U of A). IRES is to couple with the distributed database system designed for Structured PACS (S-PACS)1 to achieve the high system performance required by radiologists. IRES encompasses the "intelligence" of multiple expert radiologists. The system will predict and migrate the "old" images needed for comparison purposes during radiological exam readings from slower or remote storage devices to the local buffers of workstations. The use of IRES with the PACS Distributed Database System (DDBS) is expected to shorten the PACS system response time, save the time of radiologists in selecting films, minimize the turnaround time of the exam interpretation function, and increase diagnostic effectiveness by providing relevant images automatically. This paper presents the implementation details of this IRES prototype.

  14. Automated information retrieval using CLIPS

    NASA Technical Reports Server (NTRS)

    Raines, Rodney Doyle, III; Beug, James Lewis

    1991-01-01

    Expert systems have considerable potential to assist computer users in managing the large volume of information available to them. One possible use of an expert system is to model the information retrieval interests of a human user and then make recommendations to the user as to articles of interest. At Cal Poly, a prototype expert system written in the C Language Integrated Production System (CLIPS) serves as an Automated Information Retrieval System (AIRS). AIRS monitors a user's reading preferences, develops a profile of the user, and then evaluates items returned from the information base. When prompted by the user, AIRS returns a list of items of interest to the user. In order to minimize the impact on system resources, AIRS is designed to run in the background during periods of light system use.

  15. Desert Dust Satellite Retrieval Intercomparison

    NASA Technical Reports Server (NTRS)

    Carboni, E.; Thomas, G. E.; Sayer, A. M.; Siddans, R.; Poulsen, C. A.; Grainger, R. G.; Ahn, C.; Antoine, D.; Bevan, S.; Braak, R.; Brindley, H.; DeSouza-Mchado, S.; Deuze, J. L.; Diner, D.; Ducos, F.; Grey, W.; Hsu, C.; Kalashnikova, O. V.; Kahn, R.; North, P. R. J.; Salustro, C.; Smith, A.; Tanre, D.; Torres, O.; Veihelmann, B.

    2012-01-01

    This work provides a comparison of satellite retrievals of Saharan desert dust aerosol optical depth (AOD) during a strong dust event through March 2006. In this event, a large dust plume was transported over desert, vegetated, and ocean surfaces. The aim is to identify and understand the differences between current algorithms, and hence improve future retrieval algorithms. The satellite instruments considered are AATSR, AIRS, MERIS, MISR, MODIS, OMI, POLDER, and SEVIRI. An interesting aspect is that the different algorithms make use of different instrument characteristics to obtain retrievals over bright surfaces. These include multi-angle approaches (MISR, AATSR), polarisation measurements (POLDER), single-view approaches using solar wavelengths (OMI, MODIS), and the thermal infrared spectral region (SEVIRI, AIRS). Differences between instruments, together with the comparison of different retrieval algorithms applied to measurements from the same instrument, provide a unique insight into the performance and characteristics of the various techniques employed. As well as the intercomparison between different satellite products, the AODs have also been compared to co-located AERONET data. Despite the fact that the agreement between satellite and AERONET AODs is reasonably good for all of the datasets, there are significant differences between them when compared to each other, especially over land. These differences are partially due to differences in the algorithms, such as as20 sumptions about aerosol model and surface properties. However, in this comparison of spatially and temporally averaged data, at least as significant as these differences are sampling issues related to the actual footprint of each instrument on the heterogeneous aerosol field, cloud identification and the quality control flags of each dataset.

  16. Cue Strength as a Moderator of the Testing Effect: The Benefits of Elaborative Retrieval

    ERIC Educational Resources Information Center

    Carpenter, Shana K.

    2009-01-01

    The current study explored the elaborative retrieval hypothesis as an explanation for the testing effect: the tendency for a memory test to enhance retention more than restudying. In particular, the retrieval process during testing may activate elaborative information related to the target response, thereby increasing the chances that activation…

  17. Resolving Interference between Body Movements: Retrieval-Induced Forgetting of Motor Sequences

    ERIC Educational Resources Information Center

    Tempel, Tobias; Frings, Christian

    2013-01-01

    When body movements are stored in memory in an organized manner, linked to a common retrieval cue like the effector with which to execute the movement, interference may arise as soon as one initiates the execution of a specific body movement in the presence of the retrieval cue because related motor programs also are activated. We investigated the…

  18. Bilateral Saccadic Eye Movements and Tactile Stimulation, but Not Auditory Stimulation, Enhance Memory Retrieval

    ERIC Educational Resources Information Center

    Nieuwenhuis, Sander; Elzinga, Bernet M.; Ras, Priscilla H.; Berends, Floris; Duijs, Peter; Samara, Zoe; Slagter, Heleen A.

    2013-01-01

    Recent research has shown superior memory retrieval when participants make a series of horizontal saccadic eye movements between the memory encoding phase and the retrieval phase compared to participants who do not move their eyes or move their eyes vertically. It has been hypothesized that the rapidly alternating activation of the two hemispheres…

  19. Neural Correlates of Familiarity-Based Associative Retrieval

    ERIC Educational Resources Information Center

    Ford, Jaclyn Hennessey; Verfaellie, Mieke; Giovanello, Kelly S.

    2010-01-01

    The current study compared the neural correlates of associative retrieval of compound (unitized) stimuli and unrelated (non-unitized) stimuli. Although associative recognition was nearly identical for compounds and unrelated pairs, accurate recognition of these different pair types was associated with activation in distinct regions within the…

  20. Ranked Retrieval with Semantic Networks and Vector Spaces.

    ERIC Educational Resources Information Center

    Kulyukin, Vladimir A.; Settle, Amber

    2001-01-01

    Discussion of semantic networks and ranked retrieval focuses on two models, the semantic network model with spreading activation and the vector space model with dot product. Suggests a formal method to analyze the two models in terms of their relative performance in the same universe of objects. (Author/LRW)

  1. Computer Informational Retrieval in China: Current Situation and Future Trends.

    ERIC Educational Resources Information Center

    Bing, Wang

    1988-01-01

    Discusses the background and the current situation of computer information retrieval systems in China. Problem areas considered include: (1) lack of coordination of activities; (2) lack of data on user demand; and (3) shortages of personnel in computer science, mathematics, and systems engineering. An agenda for the future is outlined. (MES)

  2. Prefrontal Cortex Contributions to Episodic Retrieval Monitoring and Evaluation

    ERIC Educational Resources Information Center

    Cruse, Damian; Wilding, Edward L.

    2009-01-01

    Although the prefrontal cortex (PFC) plays roles in episodic memory judgments, the specific processes it supports are not understood fully. Event-related potential (ERP) studies of episodic retrieval have revealed an electrophysiological modulation--the right-frontal ERP old/new effect--which is thought to reflect activity in PFC. The functional…

  3. Geosemantic Information Retrieval Using a Geoontology

    NASA Astrophysics Data System (ADS)

    Hwang, J.

    2014-12-01

    Currently, most users prefer searching for the information using the more convenient and dynamic mobile information retrieval services to using the existing desktop PC services in the limited space, according as a lot of mobile terminals have been provided with the development of a variety of techniques. Information retrieval service using the mobile terminals has the strength that provides the personalized information results related to the users' information request anytime and anywhere, considering the users' mobility and portability. Therefore, for the information retrieval using the mobile devices I need the context awareness techniques which have been researched actively. In this thesis, I developed the context awareness ontology model for Geotourism as the representative method of the context awareness techniques to predict the user's interest and foresee the information about which retrieval results and which places the user want to get. The proposed Geotour ontology model is extended and designed from W3C Time Ontology defined in the international standards and spatial geometry feature ontology supported by OGC GeoSPARQL, so it can provide the usability and the function. That is, GeotourFeature class is the subclass of ogc:Feature defined in OGC as in Figure 1. GeotourTime class which is for expressing temporal information of a certain Geotour features is the subclass of TemporalThing of W3C. Figure 1: Relationship between the international standard ontology and the geotour ontology model A Geotour features and a geotour map describes a part of ontology to represent the GeotourFeature composed of GeotourTime class and GeotourLocation class. The highest class to represent GeotourTime and GeotourLocation is GeotourFeature class. As mentioned in the previous section, our model inherited the temporal ontology of W3C. Figure 2 describes a part of ontology to represent the GeotourFeature composed of GeotourTime class and GeotourLocation class. The highest class

  4. Microwave Soil Moisture Retrieval Under Trees

    NASA Technical Reports Server (NTRS)

    O'Neill, P.; Lang, R.; Kurum, M.; Joseph, A.; Jackson, T.; Cosh, M.

    2008-01-01

    Soil moisture is recognized as an important component of the water, energy, and carbon cycles at the interface between the Earth's surface and atmosphere. Current baseline soil moisture retrieval algorithms for microwave space missions have been developed and validated only over grasslands, agricultural crops, and generally light to moderate vegetation. Tree areas have commonly been excluded from operational soil moisture retrieval plans due to the large expected impact of trees on masking the microwave response to the underlying soil moisture. Our understanding of the microwave properties of trees of various sizes and their effect on soil moisture retrieval algorithms at L band is presently limited, although research efforts are ongoing in Europe, the United States, and elsewhere to remedy this situation. As part of this research, a coordinated sequence of field measurements involving the ComRAD (for Combined Radar/Radiometer) active/passive microwave truck instrument system has been undertaken. Jointly developed and operated by NASA Goddard Space Flight Center and George Washington University, ComRAD consists of dual-polarized 1.4 GHz total-power radiometers (LH, LV) and a quad-polarized 1.25 GHz L band radar sharing a single parabolic dish antenna with a novel broadband stacked patch dual-polarized feed, a quad-polarized 4.75 GHz C band radar, and a single channel 10 GHz XHH radar. The instruments are deployed on a mobile truck with an 19-m hydraulic boom and share common control software; real-time calibrated signals, and the capability for automated data collection for unattended operation. Most microwave soil moisture retrieval algorithms developed for use at L band frequencies are based on the tau-omega model, a simplified zero-order radiative transfer approach where scattering is largely ignored and vegetation canopies are generally treated as a bulk attenuating layer. In this approach, vegetation effects are parameterized by tau and omega, the microwave

  5. Retrieval of Mir Solar Array

    NASA Technical Reports Server (NTRS)

    Rutledge, Sharon K.; deGroh, Kim K.

    1999-01-01

    A Russian solar array panel removed in November 1997 from the non-articulating photovoltaic array on the Mir core module was returned to Earth on STS-89 in January 1998. The panel had been exposed to low Earth orbit (LEO) for 10 years prior to retrieval. The retrieval provided a unique opportunity to study the effects of the LEO environment on a functional solar array. To take advantage of this opportunity, a team composed of members from RSC-Energia (Russia), the Boeing Company, and the following NASA Centers--Johnson Space Center, Kennedy Space Center, Langley Research Center, Marshall Space Flight Center, and Lewis Research Center--was put together to analyze the array. After post-retrieval inspections at the Spacehab Facility at Kennedy in Florida, the array was shipped to Lewis in Cleveland for electrical performance tests, closeup photodocumentation, and removal of selected solar cells and blanket material. With approval from RSC-Energia, five cell pairs and their accompanying blanket and mesh material, and samples of painted handrail materials were selected for removal on the basis of their ability to provide degradation information. Sites were selected that provided different sizes and shapes of micrometeoroid impacts and different levels of surface contamination. These materials were then distributed among the team for round robin testing.

  6. Legacy Waste Retrieval from Cladding Hulls and Fuel Hardware Storage

    SciTech Connect

    Wattecamps, J.B.; Hubert, N.; Zanife, T.

    2007-07-01

    Waste generated during nuclear fuel shearing and dissolution operations from 1976 to 1998 at the UP2-400 plant at La Hague, has been stored in bulk in a silo and in metal canisters. The waste has to be retrieved and conditioned before the implementation of the shutdown program. This paper gives a general presentation of the project to retrieve and condition this waste stored in the High Activity Oxide (HAO) facility. The topics discussed include a presentation of scenarios and technical solutions as well as a presentation of AREVA NC's approach to meet schedule commitment and to minimize overall project cost. (authors)

  7. Initial retrieval sequence and blending strategy

    SciTech Connect

    Pemwell, D.L.; Grenard, C.E.

    1996-09-01

    This report documents the initial retrieval sequence and the methodology used to select it. Waste retrieval, storage, pretreatment and vitrification were modeled for candidate single-shell tank retrieval sequences. Performance of the sequences was measured by a set of metrics (for example,high-level waste glass volume, relative risk and schedule).Computer models were used to evaluate estimated glass volumes,process rates, retrieval dates, and blending strategy effects.The models were based on estimates of component inventories and concentrations, sludge wash factors and timing, retrieval annex limitations, etc.

  8. A Unified Mathematical Definition of Classical Information Retrieval.

    ERIC Educational Resources Information Center

    Dominich, Sandor

    2000-01-01

    Presents a unified mathematical definition for the classical models of information retrieval and identifies a mathematical structure behind relevance feedback. Highlights include vector information retrieval; probabilistic information retrieval; and similarity information retrieval. (Contains 118 references.) (Author/LRW)

  9. MODIS Retrievals of Cloud Optical Thickness and Particle Radius

    NASA Technical Reports Server (NTRS)

    Platnick, S.; King, M. D.; Ackerman, S. A.; Gray, M.; Moody, E.; Arnold, G. T.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) provides an unprecedented opportunity for global cloud studies with 36 spectral bands from the visible through the infrared, and spatial resolution from 250 m to 1 km at nadir. In particular, all solar window bands useful for simultaneous retrievals of cloud optical thickness and particle size (0.67, 0.86, 1.2, 1.6, 2.1, and 3.7 micron bands) are now available on a single satellite instrument/platform for the first time. An operational algorithm for the retrieval of these optical and cloud physical properties (including water path) have been developed for both liquid and ice phase clouds. The product is archived into two categories: pixel-level retrievals at 1 km spatial resolution (referred to as a Level-2 product) and global gridded statistics (Level-3 product). An overview of the MODIS cloud retrieval algorithm and early level-2 and -3 results will be presented. A number of MODIS cloud validation activities are being planned, including the recent Southern Africa Regional Science Initiative 2000 (SAFARI-2000) dry season campaign conducted in August/September 2000. The later part of the experiment concentrated on MODIS validation in the Namibian stratocumulus regime off the southwest coast of Africa. Early retrieval results from this regime will be discussed.

  10. Representational Complexity and Memory Retrieval in Language Comprehension

    PubMed Central

    Hofmeister, Philip

    2012-01-01

    Mental representations formed from words or phrases may vary considerably in their feature-based complexity. Modern theories of retrieval in sentence comprehension do not indicate how this variation and the role of encoding processes should influence memory performance. Here, memory retrieval in language comprehension is shown to be influenced by a target’s representational complexity in terms of syntactic and semantic features. Three self-paced reading experiments provide evidence that reading times at retrieval sites (but not earlier) decrease when more complex phrases occur as filler-phrases in filler-gap dependencies. The data also show that complexity-based effects are not dependent on string length, syntactic differences, or the amount of processing the stimuli elicit. Activation boosting and reduced similarity-based interference are implicated as likely sources of these complexity-based effects. PMID:22675235

  11. Using Induction to Refine Information Retrieval Strategies

    NASA Technical Reports Server (NTRS)

    Baudin, Catherine; Pell, Barney; Kedar, Smadar

    1994-01-01

    Conceptual information retrieval systems use structured document indices, domain knowledge and a set of heuristic retrieval strategies to match user queries with a set of indices describing the document's content. Such retrieval strategies increase the set of relevant documents retrieved (increase recall), but at the expense of returning additional irrelevant documents (decrease precision). Usually in conceptual information retrieval systems this tradeoff is managed by hand and with difficulty. This paper discusses ways of managing this tradeoff by the application of standard induction algorithms to refine the retrieval strategies in an engineering design domain. We gathered examples of query/retrieval pairs during the system's operation using feedback from a user on the retrieved information. We then fed these examples to the induction algorithm and generated decision trees that refine the existing set of retrieval strategies. We found that (1) induction improved the precision on a set of queries generated by another user, without a significant loss in recall, and (2) in an interactive mode, the decision trees pointed out flaws in the retrieval and indexing knowledge and suggested ways to refine the retrieval strategies.

  12. Associative Retrieval Processes in the Human Medial Temporal Lobe: Hippocampal Retrieval Success and CA1 Mismatch Detection

    ERIC Educational Resources Information Center

    Chen, Janice; Olsen, Rosanna K.; Preston, Alison R.; Glover, Gary H.; Wagner, Anthony D.

    2011-01-01

    Hippocampal subfields CA3 and CA1 are hypothesized to differentially support the generation of associative predictions and the detection of associative mismatches, respectively. Using high-resolution functional MRI, we examined hippocampal subfield activation during associative retrieval and during subsequent comparisons of memory to matching or…

  13. The CIRSE Retrievable IVC Filter Registry: Retrieval Success Rates in Practice.

    PubMed

    Lee, M J; Valenti, D; de Gregorio, M A; Minocha, J; Rimon, U; Pellerin, O

    2015-12-01

    CIRSE established a registry of retrievable filter use with the primary aim of determining the success of IVC Filter retrieval and associated complications. Secondary endpoints included filter indications, imaging strategies before retrieval, filter dwell times, and anticoagulation status. A web-based electronic registry was hosted between 01/12/2010 and 30/06/2012. Data entry occurred at the date of IVC filter retrieval and included items such as filter type, indication for filter insertion, access route, dwell time, retrieval success, complications, reasons for failed retrieval, and anticoagulation status. 671 filter retrievals were entered (male:female 333:295, mean age 55, median 57). Retrieval data were not entered in 43/671 leaving 628 patients for analysis. The 4 commonest retrievable filters used were the Celect in 182 patients, the OPTEASE in 161, ALN in 120, and Gunther Tulip in 98. Filters were inserted for absolute indications 40%, relative indications in 31%, and prophylactic in 24%, with 5% missing. Mean filter dwell time was 90 days. Filters were successfully retrieved in 576/628 patients (92%). The mean dwell time for successful retrievals was 85 days versus 145 days for unsuccessful retrievals (p = 0.001). Major complications occurred in 2 patients (0.03%). In summary, the CIRSE retrievable filter registry demonstrates a retrieval rate of 92% across a range of filter types, with a low major complication rate, reflecting current practice. There is an increase in trend of retrievable filter use for relative and prophylactic indications. PMID:25933644

  14. Transuranic (TRU) Waste Phase I Retrieval Plan

    SciTech Connect

    MCDONALD, K.M.

    1999-08-27

    Phase I retrieval of post-1970 TRU wastes from burial ground 218-W-4C can be done in a safe, efficient, and cost-effective manner. Initiating TRU retrieval by retrieving uncovered drums from Trenches 1, 20, and 29, will allow retrieval to begin under the current SWBG safety authorization basis. The retrieval of buried drums from Trenches 1, 4, 20, and 29, which will require excavation, will commence once the uncovered drum are retrieved. This phased approach allows safety analysis for drum venting and drum module excavation to be completed and approved before the excavation proceeds. In addition, the lessons learned and the operational experience gained from the retrieval of uncovered drums can be applied to the more complicated retrieval of the buried drums. Precedents that have been set at SRS and LANL to perform retrieval without a trench cover, in the open air, should be followed. Open-air retrieval will result in significant cost savings over the original plans for Phase I retrieval (Project W-113). Based on LANL and SRS experience, open-air retrieval will have no adverse impacts to the environment or to the health and safety of workers or the public. Assaying the waste in the SWBG using a mobile assay system, will result in additional cost savings. It is expected that up to 50% of the suspect-TRU wastes will assay as LLW, allowing those waste to remain disposed of in the SWBG. Further processing, with its associated costs, will only occur to the portion of the waste that is verified to be TRU. Retrieval should be done, to the extent possible, under the current SWBG safety authorization basis as a normal part of SWBG operations. The use of existing personnel and existing procedures should be optimized. By working retrieval campaigns, typically during the slow months, it is easier to coordinate the availability of necessary operations personnel, and it is easier to coordinate the availability of a mobile assay vendor.

  15. Covert retrieval practice benefits retention as much as overt retrieval practice.

    PubMed

    Smith, Megan A; Roediger, Henry L; Karpicke, Jeffrey D

    2013-11-01

    Many experiments provide evidence that practicing retrieval benefits retention relative to conditions of no retrieval practice. Nearly all prior research has employed retrieval practice requiring overt responses, but a few experiments have shown that covert retrieval also produces retention advantages relative to control conditions. However, direct comparisons between overt and covert retrieval are scarce: Does covert retrieval-thinking of but not producing responses-on a first test produce the same benefit as overt retrieval on a criterial test given later? We report 4 experiments that address this issue by comparing retention on a second test following overt or covert retrieval on a first test. In Experiment 1 we used a procedure designed to ensure that subjects would retrieve on covert as well as overt test trials and found equivalent testing effects in the 2 cases. In Experiment 2 we replicated these effects using a procedure that more closely mirrored natural retrieval processes. In Experiment 3 we showed that overt and covert retrieval produced equivalent testing effects after a 2-day delay. Finally, in Experiment 4 we showed that covert retrieval benefits retention more than restudying. We conclude that covert retrieval practice is as effective as overt retrieval practice, a conclusion that contravenes hypotheses in the literature proposing that overt responding is better. This outcome has an important educational implication: Students can learn as much from covert self-testing as they would from overt responding. PMID:23815513

  16. Solar Occultation Retrieval Algorithm Development

    NASA Technical Reports Server (NTRS)

    Lumpe, Jerry D.

    2004-01-01

    This effort addresses the comparison and validation of currently operational solar occultation retrieval algorithms, and the development of generalized algorithms for future application to multiple platforms. initial development of generalized forward model algorithms capable of simulating transmission data from of the POAM II/III and SAGE II/III instruments. Work in the 2" quarter will focus on: completion of forward model algorithms, including accurate spectral characteristics for all instruments, and comparison of simulated transmission data with actual level 1 instrument data for specific occultation events.

  17. The validation of AIRS retrievals

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.; Olsen, Edward T.; Chen, Luke L.; Hagan, Denise E.; Fishbein, Evan; McMillin, Larry; Zhou, Jiang; McMillan, Wallace W.

    2003-01-01

    The initial validation of Atmospheric Infrared Sounder (SIRS) experiment retrievals were completed in August 2003 as part of public release of version 3.0 data. The associated analyses are reported at http://daac.gsfc.nasa.gov/atmodyn/airs/, where data may be accessed. Here we describe some of those analyses, with an emphasis on cloud cleared radiances, atmospheric temperature profiles, sea surface temperature, total water vapor and atmospheric water vapor profiles. The results are applicable over ocean in the latitude band +/-40 degrees.

  18. A temporal shift in the circuits mediating retrieval of fear memory.

    PubMed

    Do-Monte, Fabricio H; Quiñones-Laracuente, Kelvin; Quirk, Gregory J

    2015-03-26

    Fear memories allow animals to avoid danger, thereby increasing their chances of survival. Fear memories can be retrieved long after learning, but little is known about how retrieval circuits change with time. Here we show that the dorsal midline thalamus of rats is required for the retrieval of auditory conditioned fear at late (24 hours, 7 days, 28 days), but not early (0.5 hours, 6 hours) time points after learning. Consistent with this, the paraventricular nucleus of the thalamus (PVT), a subregion of the dorsal midline thalamus, showed increased c-Fos expression only at late time points, indicating that the PVT is gradually recruited for fear retrieval. Accordingly, the conditioned tone responses of PVT neurons increased with time after training. The prelimbic (PL) prefrontal cortex, which is necessary for fear retrieval, sends dense projections to the PVT. Retrieval at late time points activated PL neurons projecting to the PVT, and optogenetic silencing of these projections impaired retrieval at late, but not early, time points. In contrast, silencing of PL inputs to the basolateral amygdala impaired retrieval at early, but not late, time points, indicating a time-dependent shift in retrieval circuits. Retrieval at late time points also activated PVT neurons projecting to the central nucleus of the amygdala, and silencing these projections at late, but not early, time points induced a persistent attenuation of fear. Thus, the PVT may act as a crucial thalamic node recruited into cortico-amygdalar networks for retrieval and maintenance of long-term fear memories. PMID:25600268

  19. A General Uncertainty Quantification Methodology for Cloud Microphysical Property Retrievals

    NASA Astrophysics Data System (ADS)

    Tang, Q.; Xie, S.; Chen, X.; Zhao, C.

    2014-12-01

    The US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program provides long-term (~20 years) ground-based cloud remote sensing observations. However, there are large uncertainties in the retrieval products of cloud microphysical properties based on the active and/or passive remote-sensing measurements. To address this uncertainty issue, a DOE Atmospheric System Research scientific focus study, Quantification of Uncertainties in Cloud Retrievals (QUICR), has been formed. In addition to an overview of recent progress of QUICR, we will demonstrate the capacity of an observation-based general uncertainty quantification (UQ) methodology via the ARM Climate Research Facility baseline cloud microphysical properties (MICROBASE) product. This UQ method utilizes the Karhunen-Loéve expansion (KLE) and Central Limit Theorems (CLT) to quantify the retrieval uncertainties from observations and algorithm parameters. The input perturbations are imposed on major modes to take into account the cross correlations between input data, which greatly reduces the dimension of random variables (up to a factor of 50) and quantifies vertically resolved full probability distribution functions of retrieved quantities. Moreover, this KLE/CLT approach has the capability of attributing the uncertainties in the retrieval output to individual uncertainty source and thus sheds light on improving the retrieval algorithm and observations. We will present the results of a case study for the ice water content at the Southern Great Plains during an intensive observing period on March 9, 2000. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  20. Technology Successes in Hanford Tank Waste Storage and Retrieval

    SciTech Connect

    Cruz, E. J.

    2002-02-26

    The U. S. Department of Energy (DOE), Office of River Protection (ORP) is leading the River Protection Project (RPP), which is responsible for dispositioning approximately 204,000 cubic meters (54 million gallons) of high-level radioactive waste that has accumulated in 177 large underground tanks at the Hanford Site since 1944. The RPP is comprised of five major elements: storage of the waste, retrieval of the waste from the tanks, treatment of the waste, disposal of treated waste, and closure of the tank facilities. Approximately 3785 cubic meters (1 million gallons) of waste have leaked from the older ''single-shell tanks.'' Sixty-seven of the 147 single shell tanks are known or assumed ''leakers.'' These leaks have resulted in contaminant plumes that extend from the tank to the groundwater in a number of tank farms. Retrieval and closure of the leaking tanks complicates the ORP technical challenge because cleanup decisions must consider the impacts of past leaks along with a strategy for retrieving the waste in the tanks. Completing the RPP mission as currently planned and with currently available technologies will take several decades and tens of billions of dollars. RPP continue to pursue the benefits from deploying technologies that reduce risk to human health and the environment, as well as, the cost of cleanup. This paper discusses some of the recent technology partnering activities with the DOE Office of Science and Technology activities in tank waste retrieval and storage.

  1. The Aquarius Salinity Retrieval Algorithm

    NASA Technical Reports Server (NTRS)

    Meissner, Thomas; Wentz, Frank; Hilburn, Kyle; Lagerloef, Gary; Le Vine, David

    2012-01-01

    The first part of this presentation gives an overview over the Aquarius salinity retrieval algorithm. The instrument calibration [2] converts Aquarius radiometer counts into antenna temperatures (TA). The salinity retrieval algorithm converts those TA into brightness temperatures (TB) at a flat ocean surface. As a first step, contributions arising from the intrusion of solar, lunar and galactic radiation are subtracted. The antenna pattern correction (APC) removes the effects of cross-polarization contamination and spillover. The Aquarius radiometer measures the 3rd Stokes parameter in addition to vertical (v) and horizontal (h) polarizations, which allows for an easy removal of ionospheric Faraday rotation. The atmospheric absorption at L-band is almost entirely due to molecular oxygen, which can be calculated based on auxiliary input fields from numerical weather prediction models and then successively removed from the TB. The final step in the TA to TB conversion is the correction for the roughness of the sea surface due to wind, which is addressed in more detail in section 3. The TB of the flat ocean surface can now be matched to a salinity value using a surface emission model that is based on a model for the dielectric constant of sea water [3], [4] and an auxiliary field for the sea surface temperature. In the current processing only v-pol TB are used for this last step.

  2. Biomedical information retrieval across languages.

    PubMed

    Daumke, Philipp; Markü, Kornél; Poprat, Michael; Schulz, Stefan; Klar, Rüdiger

    2007-06-01

    This work presents a new dictionary-based approach to biomedical cross-language information retrieval (CLIR) that addresses many of the general and domain-specific challenges in current CLIR research. Our method is based on a multilingual lexicon that was generated partly manually and partly automatically, and currently covers six European languages. It contains morphologically meaningful word fragments, termed subwords. Using subwords instead of entire words significantly reduces the number of lexical entries necessary to sufficiently cover a specific language and domain. Mediation between queries and documents is based on these subwords as well as on lists of word-n-grams that are generated from large monolingual corpora and constitute possible translation units. The translations are then sent to a standard Internet search engine. This process makes our approach an effective tool for searching the biomedical content of the World Wide Web in different languages. We evaluate this approach using the OHSUMED corpus, a large medical document collection, within a cross-language retrieval setting. PMID:17541863

  3. Retrieving fear memories, as time goes by….

    PubMed

    Do Monte, F H; Quirk, G J; Li, B; Penzo, M A

    2016-08-01

    Research in fear conditioning has provided a comprehensive picture of the neuronal circuit underlying the formation of fear memories. In contrast, our understanding of the retrieval of fear memories is much more limited. This disparity may stem from the fact that fear memories are not rigid, but reorganize over time. To bring some clarity and raise awareness about the time-dependent dynamics of retrieval circuits, we review current evidence on the neuronal circuitry participating in fear memory retrieval at both early and late time points following auditory fear conditioning. We focus on the temporal recruitment of the paraventricular nucleus of the thalamus (PVT) for the retrieval and maintenance of fear memories. Finally, we speculate as to why retrieval circuits change with time, and consider the functional strategy of recruiting structures not previously considered as part of the retrieval circuit. PMID:27217148

  4. Scalable ranked retrieval using document images

    NASA Astrophysics Data System (ADS)

    Jain, Rajiv; Oard, Douglas W.; Doermann, David

    2013-12-01

    Despite the explosion of text on the Internet, hard copy documents that have been scanned as images still play a significant role for some tasks. The best method to perform ranked retrieval on a large corpus of document images, however, remains an open research question. The most common approach has been to perform text retrieval using terms generated by optical character recognition. This paper, by contrast, examines whether a scalable segmentation-free image retrieval algorithm, which matches sub-images containing text or graphical objects, can provide additional benefit in satisfying a user's information needs on a large, real world dataset. Results on 7 million scanned pages from the CDIP v1.0 test collection show that content based image retrieval finds a substantial number of documents that text retrieval misses, and that when used as a basis for relevance feedback can yield improvements in retrieval effectiveness.

  5. ARM Cloud Retrieval Ensemble Data Set (ACRED)

    SciTech Connect

    Zhao, C; Xie, S; Klein, SA; McCoy, R; Comstock, JM; Delanoë, J; Deng, M; Dunn, M; Hogan, RJ; Jensen, MP; Mace, GG; McFarlane, SA; O’Connor, EJ; Protat, A; Shupe, MD; Turner, D; Wang, Z

    2011-09-12

    This document describes a new Atmospheric Radiation Measurement (ARM) data set, the ARM Cloud Retrieval Ensemble Data Set (ACRED), which is created by assembling nine existing ground-based cloud retrievals of ARM measurements from different cloud retrieval algorithms. The current version of ACRED includes an hourly average of nine ground-based retrievals with vertical resolution of 45 m for 512 layers. The techniques used for the nine cloud retrievals are briefly described in this document. This document also outlines the ACRED data availability, variables, and the nine retrieval products. Technical details about the generation of ACRED, such as the methods used for time average and vertical re-grid, are also provided.

  6. Selective memory retrieval of auditory what and auditory where involves the ventrolateral prefrontal cortex

    PubMed Central

    Kostopoulos, Penelope; Petrides, Michael

    2016-01-01

    There is evidence from the visual, verbal, and tactile memory domains that the midventrolateral prefrontal cortex plays a critical role in the top–down modulation of activity within posterior cortical areas for the selective retrieval of specific aspects of a memorized experience, a functional process often referred to as active controlled retrieval. In the present functional neuroimaging study, we explore the neural bases of active retrieval for auditory nonverbal information, about which almost nothing is known. Human participants were scanned with functional magnetic resonance imaging (fMRI) in a task in which they were presented with short melodies from different locations in a simulated virtual acoustic environment within the scanner and were then instructed to retrieve selectively either the particular melody presented or its location. There were significant activity increases specifically within the midventrolateral prefrontal region during the selective retrieval of nonverbal auditory information. During the selective retrieval of information from auditory memory, the right midventrolateral prefrontal region increased its interaction with the auditory temporal region and the inferior parietal lobule in the right hemisphere. These findings provide evidence that the midventrolateral prefrontal cortical region interacts with specific posterior cortical areas in the human cerebral cortex for the selective retrieval of object and location features of an auditory memory experience. PMID:26831102

  7. Selective memory retrieval of auditory what and auditory where involves the ventrolateral prefrontal cortex.

    PubMed

    Kostopoulos, Penelope; Petrides, Michael

    2016-02-16

    There is evidence from the visual, verbal, and tactile memory domains that the midventrolateral prefrontal cortex plays a critical role in the top-down modulation of activity within posterior cortical areas for the selective retrieval of specific aspects of a memorized experience, a functional process often referred to as active controlled retrieval. In the present functional neuroimaging study, we explore the neural bases of active retrieval for auditory nonverbal information, about which almost nothing is known. Human participants were scanned with functional magnetic resonance imaging (fMRI) in a task in which they were presented with short melodies from different locations in a simulated virtual acoustic environment within the scanner and were then instructed to retrieve selectively either the particular melody presented or its location. There were significant activity increases specifically within the midventrolateral prefrontal region during the selective retrieval of nonverbal auditory information. During the selective retrieval of information from auditory memory, the right midventrolateral prefrontal region increased its interaction with the auditory temporal region and the inferior parietal lobule in the right hemisphere. These findings provide evidence that the midventrolateral prefrontal cortical region interacts with specific posterior cortical areas in the human cerebral cortex for the selective retrieval of object and location features of an auditory memory experience. PMID:26831102

  8. PICTURES OF A SUSPECT-TRU RETRIEVAL

    SciTech Connect

    GADD, R.R.

    2007-05-24

    Retrieving ''suspect'' transuranic (TRU) waste from the Hanford Site's low-level waste burial grounds is a tall order, due to conditions that have changed as the work progresses. Project personnel developed several new methods for handling the waste that other retrieval operations may find useful. The Waste Retrieval Project is operated by Fluor Hanford, a prime contractor for the U.S. Department of Energy's Richland Operations Office since 1996.

  9. Magnetite-supported sulfonic acid: a retrievable nanocatalyst for the Ritter reaction and multicomponent reactions

    EPA Science Inventory

    Magnetite-sulfonic acid (NanocatFe-OSO3H), prepared by wet-impregnation method, serves as a magnetically retrievable sustainable catalyst for the Ritter reaction which can be used in several reaction cycles without any loss of activity.

  10. Medical Image Retrieval: Past and Present

    PubMed Central

    Hwang, Kyung Hoon; Lee, Haejun

    2012-01-01

    With the widespread dissemination of picture archiving and communication systems (PACSs) in hospitals, the amount of imaging data is rapidly increasing. Effective image retrieval systems are required to manage these complex and large image databases. The authors reviewed the past development and the present state of medical image retrieval systems including text-based and content-based systems. In order to provide a more effective image retrieval service, the intelligent content-based retrieval systems combined with semantic systems are required. PMID:22509468

  11. Wellhead bowl protector and retrieving tool

    SciTech Connect

    Young, J.A.

    1991-09-03

    This patent describes improvement in a wellhead protection system including a wear bushing and a retrieving tool. The improvement comprises a wear bushing supported within the wellhead, wherein the wear bushing includes an enlarged upper end having an external support shoulder for engagement with an internal support shoulder formed in the wellhead; wherein the wear bushing further includes an internal circumferential slot intersected by at least one vertically extending slot, the vertical slot extending from the circumferential slot to the upper end of the wear bushing; a retrieving tool having at least one outwardly biased, retractable lug member mounted thereon; and wherein the retrieving tool includes an enlarged portion adapted to be received within the enlarged upper end of the wear bushing. This patent also describes a method of retrieving a wear bushing from a wellhead comprising the steps of: lowering a retrieving tool into the wellhead for locking engagement with the wear bushing; aligning the retrieving tool with the wear bushing for automatically forcing lug members carried by the retrieving tool outwardly into locking engagement with the wear bushing; monitoring drill string weight for determining engagement of the retrieving tool with the wear bushing, wherein a substantial decrease in drill string weight is an indication that the retrieving tool is engaged with the wear bushing; and removing the wear bushing from the wellhead.

  12. Evaluating performance of biomedical image retrieval systems--an overview of the medical image retrieval task at ImageCLEF 2004-2013.

    PubMed

    Kalpathy-Cramer, Jayashree; de Herrera, Alba García Seco; Demner-Fushman, Dina; Antani, Sameer; Bedrick, Steven; Müller, Henning

    2015-01-01

    Medical image retrieval and classification have been extremely active research topics over the past 15 years. Within the ImageCLEF benchmark in medical image retrieval and classification, a standard test bed was created that allows researchers to compare their approaches and ideas on increasingly large and varied data sets including generated ground truth. This article describes the lessons learned in ten evaluation campaigns. A detailed analysis of the data also highlights the value of the resources created. PMID:24746250

  13. Evaluating performance of biomedical image retrieval systems – an overview of the medical image retrieval task at ImageCLEF 2004–2013

    PubMed Central

    Kalpathy-Cramer, Jayashree; de Herrera, Alba García Seco; Demner-Fushman, Dina; Antani, Sameer; Bedrick, Steven; Müller, Henning

    2014-01-01

    Medical image retrieval and classification have been extremely active research topics over the past 15 years. With the ImageCLEF benchmark in medical image retrieval and classification a standard test bed was created that allows researchers to compare their approaches and ideas on increasingly large and varied data sets including generated ground truth. This article describes the lessons learned in ten evaluations campaigns. A detailed analysis of the data also highlights the value of the resources created. PMID:24746250

  14. Frontal-posterior theta oscillations reflect memory retrieval during sentence comprehension.

    PubMed

    Meyer, Lars; Grigutsch, Maren; Schmuck, Noura; Gaston, Phoebe; Friederici, Angela D

    2015-10-01

    Successful working-memory retrieval requires that items be retained as distinct units. At the neural level, it has been shown that theta-band oscillatory power increases with the number of to-be-distinguished items during working-memory retrieval. Here we hypothesized that during sentence comprehension, verbal-working-memory retrieval demands lead to increased theta power over frontal cortex, supposedly supporting the distinction amongst stored items during verbal-working-memory retrieval. Also, synchronicity may increase between the frontal cortex and the posterior cortex, with the latter supposedly supporting item retention. We operationalized retrieval by using pronouns, which refer to and trigger the retrieval of antecedent nouns from a preceding sentence part. Retrieval demand was systematically varied by changing the pronoun antecedent: Either, it was non-embedded in the preceding main clause, and thus easy-to-retrieve across a single clause boundary, or embedded in the preceding subordinate clause, and thus hard-to-retrieve across a double clause boundary. We combined electroencephalography (EEG), scalp-level time-frequency analysis, source localization, and source-level coherence analysis, observing a frontal-midline and broad left-hemispheric theta-power increase for embedded-antecedent compared to non-embedded-antecedent retrieval. Sources were localized to left-frontal, left-parietal, and bilateral-inferior-temporal cortices. Coherence analyses suggested synchronicity between left-frontal and left-parietal and between left-frontal and right-inferior-temporal cortices. Activity of an array of left-frontal, left-parietal, and bilateral-inferior-temporal cortices may thus assist retrieval during sentence comprehension, potentially indexing the orchestration of item distinction, verbal working memory, and long-term memory. Our results extend prior findings by mapping prior knowledge on the functional role of theta oscillations onto processes genuine to human

  15. A synergisitic Neural Network Soil Moisture Retrieval Algorithm for SMAP

    NASA Astrophysics Data System (ADS)

    Kolassa, J.; Reichle, R. H.; Gentine, P.; Prigent, C.; Aires, F.; Fang, B.

    2015-12-01

    A Neural Network (NN)-based algorithm is developed to retrieve surface soil moisture from Soil Moisture Active/Passive (SMAP) microwave observations. This statistical approach serves as an alternative to the official Radiative Transfer (RT) based SMAP retrieval algorithm, since it avoids an explicit formulation of the RT processes as well as the use of often uncertain or unavailable a priori knowledge for additional surface parameters. The NN algorithm is calibrated on observations from the SMAP radiometer and radar as well as surface soil moisture fields from the MERRA-2 reanalysis. To highlight different physical aspects of the satellite signals and to maximize the soil moisture information, different preprocessing techniques of the SMAP data are investigated. These include an analysis of radiometer polarization and diurnal indices to isolate the surface temperature contribution, as well as the radar co- and cross-polarized channels to account for vegetation effects. A major difference with respect to the official retrieval is the increased importance given to the information provided by the SMAP radar or other active sensors, utilizing not only the relative spatial structures, but also the absolute soil moisture information provided. The NN methodology combines multiple sensor observations in a data fusion approach and is thus able to fully exploit the complementarity of the information provided by the different instruments. The algorithm is used to compute global estimates of surface soil moisture and evaluated against retrieved soil moisture from SMOS as well as in situ observations from the International Soil Moisture Network (ISMN). The calibration on MERRA-2 data means that the NN retrieval algorithm functions as the model operator in a data assimilation framework yielding soil moisture estimates that are very compatible with the model. This could facilitate the assimilation of SMAP observations into land surface and numerical weather prediction models.

  16. Trends in Research on Information Retrieval--The Potential for Improvements in Conventional Boolean Retrieval Systems.

    ERIC Educational Resources Information Center

    Radecki, Tadeusz

    1988-01-01

    Discusses the inability of the standard Boolean logic model of information retrieval to deal effectively with the inherent fallibility of retrieval decisions. Recent advances in information retrieval research are reviewed, and their practical potential for overcoming the deficiencies of the Boolean model is examined. (45 references) (Author/CLB)

  17. MODIS Retrieval of Dust Aerosol

    NASA Technical Reports Server (NTRS)

    Remer, Lorraine A.; Kaufman, Yoram J.; Tanre, Didier

    2003-01-01

    The MODerate resolution Imaging Spectroradiometer (MODIS) currently aboard both the Terra and Aqua satellites produces a suite of products designed to characterize global aerosol distribution, optical thickness and particle size. Never before has a space-borne instrument been able to provide such detailed information, operationally, on a nearly global basis every day. The three years of Terra-MODIS data have been validated by comparing with co-located AERONET observations of aerosol optical thickness and derivations of aerosol size parameters. Some 8000 comparison points located at 133 AERONET sites around the globe show that the MODIS aerosol optical thickness retrievals are accurate to within the pre-launch expectations. However, the validation in regions dominated by desert dust is less accurate than in regions dominated by fine mode aerosol or background marine sea salt. The discrepancy is most apparent in retrievals of aerosol size parameters over ocean. In dust situations, the MODIS algorithm tends to under predict particle size because the reflectances at top of atmosphere measured by MODIS exhibit the stronger spectral signature expected by smaller particles. This pattern is consistent with the angular and spectral signature of non-spherical particles. All possible aerosol models in the MODIS Look-Up Tables were constructed from Mie theory, assuming a spherical shape. Using a combination of MODIS and AERONET observations, in regimes dominated by desert dust, we construct phase functions, empirically, with no assumption of particle shape. These new phase functions are introduced into the MODIS algorithm, in lieu of the original options for large dust-like particles. The results will be analyzed and examined.

  18. Acute stress and episodic memory retrieval: neurobiological mechanisms and behavioral consequences.

    PubMed

    Gagnon, Stephanie A; Wagner, Anthony D

    2016-04-01

    Episodic retrieval allows people to access memories from the past to guide current thoughts and decisions. In many real-world situations, retrieval occurs under conditions of acute stress, either elicited by the retrieval task or driven by other, unrelated concerns. Memory under such conditions may be hindered, as acute stress initiates a cascade of neuromodulatory changes that can impair episodic retrieval. Here, we review emerging evidence showing that dissociable stress systems interact over time, influencing neural function. In addition to the adverse effects of stress on hippocampal-dependent retrieval, we consider how stress biases attention and prefrontal cortical function, which could further affect controlled retrieval processes. Finally, we consider recent data indicating that stress at retrieval increases activity in a network of brain regions that enable reflexive, rapid responding to upcoming threats, while transiently taking offline regions supporting flexible, goal-directed thinking. Given the ubiquity of episodic memory retrieval in everyday life, it is critical to understand the theoretical and applied implications of acute stress. The present review highlights the progress that has been made, along with important open questions. PMID:26799371

  19. Evidence of semantic clustering in letter-cued word retrieval.

    PubMed

    Sung, Kyongje; Gordon, Barry; Yang, Sujeong; Schretlen, David J

    2013-01-01

    Letter-cued word fluency is conceptualized as a phonemically guided word retrieval process. Accordingly, word clusters typically are defined solely by their phonemic similarity. We investigated semantic clustering in two letter-cued (P and S) word fluency task performances by 315 healthy adults, each for 1 min. Singular value decomposition (SVD) and generalized topological overlap measure (GTOM) were applied to verbal outputs to conservatively extract clusters of high-frequency words. The results generally confirmed phonemic clustering. However, we also found considerable semantic/associative clusters of words (e.g., pen, pencil, and paper), and some words showed both phonemic and semantic associations within a single cluster (e.g., pair, pear, peach). We conclude that letter-cued fluency is not necessarily a purely phonemic word retrieval process. Strong automatic semantic activation mechanisms play an important role in letter-cued lexical retrieval. Theoretical conceptualizations of the word retrieval process with phonemic cues may also need to be reexamined in light of these analyses. PMID:24134125

  20. Memory retrieval along the proximodistal axis of CA1.

    PubMed

    Nakazawa, Yuki; Pevzner, Aleksandr; Tanaka, Kazumasa Z; Wiltgen, Brian J

    2016-09-01

    The proximal and distal segments of CA1 are thought to perform distinct computations. Neurons in proximal CA1 are reciprocally connected with the medial entorhinal cortex (MEC) and exhibit precise spatial firing. In contrast, cells in distal CA1 communicate with the lateral entorhinal cortex (LEC), exhibit more diffuse spatial firing and are affected by the presence of objects in the environment. To determine if these segments make unique contributions to memory retrieval, we examined cellular activity along the proximodistal axis of CA1 using transgenic reporter mice. Neurons tagged during context learning in proximal CA1 were more likely to be reactivated during testing than those in distal CA1. This was true following context fear conditioning and after exposure to a novel environment. Reactivation was also higher in brain regions connected to proximal CA1 (MEC, distal CA3) than those connected to the distal segment (LEC, proximal CA3). To examine contributions to memory retrieval, we performed neurotoxic lesions of proximal or distal CA1 after training. Lesions of the proximal segment significantly impaired memory retrieval while damage to distal CA1 had no effect. These data suggest that context memories are retrieved by a hippocampal microcircuit that involves the proximal but not distal segment of CA1. © 2016 Wiley Periodicals, Inc. PMID:27068122

  1. A navigation and control system for an autonomous rescue vehicle in the space station environment

    NASA Technical Reports Server (NTRS)

    Merkel, Lawrence

    1991-01-01

    A navigation and control system was designed and implemented for an orbital autonomous rescue vehicle envisioned to retrieve astronauts or equipment in the case that they become disengaged from the space station. The rescue vehicle, termed the Extra-Vehicular Activity Retriever (EVAR), has an on-board inertial measurement unit ahd GPS receivers for self state estimation, a laser range imager (LRI) and cameras for object state estimation, and a data link for reception of space station state information. The states of the retriever and objects (obstacles and the target object) are estimated by inertial state propagation which is corrected via measurements from the GPS, the LRI system, or the camera system. Kalman filters are utilized to perform sensor fusion and estimate the state propagation errors. Control actuation is performed by a Manned Maneuvering Unit (MMU). Phase plane control techniques are used to control the rotational and translational state of the retriever. The translational controller provides station-keeping or motion along either Clohessy-Wiltshire trajectories or straight line trajectories in the LVLH frame of any sufficiently observed object or of the space station. The software was used to successfully control a prototype EVAR on an air bearing floor facility, and a simulated EVAR operating in a simulated orbital environment. The design of the navigation system and the control system are presented. Also discussed are the hardware systems and the overall software architecture.

  2. The Aquarius Salinity Retrieval Algorithm: Early Results

    NASA Technical Reports Server (NTRS)

    Meissner, Thomas; Wentz, Frank J.; Lagerloef, Gary; LeVine, David

    2012-01-01

    (cal/val) activity needs to be completed. This is necessary in order to tune the inputs to the algorithm and remove biases that arise due to the instrument calibration, foremost the values of the noise diode injection temperatures and the losses that occur in the feedhorns. This is the subject of the second part of our presentation. The basic tool is to analyze the observed difference between the Aquarius measured TA and an expected TA that is computed from a reference salinity field. It is also necessary to derive a relation between the scatterometer backscatter measurements and the radiometer emissivity that is induced by surface winds. In order to do this we collocate Aquarius radiometer and scatterometer measurements with wind speed retrievals from the WindSat and SSMIS F17 microwave radiometers. Both of these satellites fly in orbits that have the same equatorial ascending crossing time (6 pm) as the Aquarius/SAC-D observatory. Rain retrievals from WindSat and SSMIS F 17 can be used to remove Aquarius observations that are rain contaminated. A byproduct of this analysis is a prediction for the wind-induced sea surface emissivity at L-band.

  3. Exploiting Multimodal Context in Image Retrieval.

    ERIC Educational Resources Information Center

    Srihari, Rohini K.; Zhang, Zhongfei

    1999-01-01

    Finding information on the Web without encountering numerous false positives poses a challenge to multimedia information retrieval systems (MMIR). This research focuses on improving precision and recall in an MMIR system by interactively combining text processing with image processing in both the indexing and retrieval phases. A picture search…

  4. Retrieval from Memory: Vulnerable or Inviolable?

    ERIC Educational Resources Information Center

    Jones, Dylan M.; Marsh, John E.; Hughes, Robert W.

    2012-01-01

    We show that retrieval from semantic memory is vulnerable even to the mere presence of speech. Irrelevant speech impairs semantic fluency--namely, lexical retrieval cued by a semantic category name--but only if it is meaningful (forward speech compared to reversed speech or words compared to nonwords). Moreover, speech related semantically to the…

  5. Indexing and Retrieval for the Web.

    ERIC Educational Resources Information Center

    Rasmussen, Edie M.

    2003-01-01

    Explores current research on indexing and ranking as retrieval functions of search engines on the Web. Highlights include measuring search engine stability; evaluation of Web indexing and retrieval; Web crawlers; hyperlinks for indexing and ranking; ranking for metasearch; document structure; citation indexing; relevance; query evaluation;…

  6. Experiments in Multi-Lingual Information Retrieval.

    ERIC Educational Resources Information Center

    Salton, Gerard

    A comparison was made of the performance in an automatic information retrieval environment of user queries and document abstracts available in natural language form in both English and French. The results obtained indicate that the automatic indexing and retrieval techniques actually used appear equally effective in handling the query and document…

  7. Memory Retrieval and Interference: Working Memory Issues

    ERIC Educational Resources Information Center

    Radvansky, Gabriel A.; Copeland, David E.

    2006-01-01

    Working memory capacity has been suggested as a factor that is involved in long-term memory retrieval, particularly when that retrieval involves a need to overcome some sort of interference (Bunting, Conway, & Heitz, 2004; Cantor & Engle, 1993). Previous work has suggested that working memory is related to the acquisition of information during…

  8. Information Retrieval beyond the Text Document.

    ERIC Educational Resources Information Center

    Rui, Yong; Ortega, Michael; Huang, Thomas S.; Mehrotra, Sharad

    1999-01-01

    Reports some of the progress made over the years toward exploring information beyond the text domain. Describes the Multimedia Analysis and Retrieval Systems (MARS), developed to increase access to non-textual information. Addresses the following aspects of MARS: (1) visual feature extraction; (2) retrieval models; (3) query reformulation…

  9. Facilitating Internet-Scale Code Retrieval

    ERIC Educational Resources Information Center

    Bajracharya, Sushil Krishna

    2010-01-01

    Internet-Scale code retrieval deals with the representation, storage, and access of relevant source code from a large amount of source code available on the Internet. Internet-Scale code retrieval systems support common emerging practices among software developers related to finding and reusing source code. In this dissertation we focus on some…

  10. Unsuccessful Retrieval Attempts Enhance Subsequent Learning

    ERIC Educational Resources Information Center

    Kornell, Nate; Hays, Matthew Jensen; Bjork, Robert A.

    2009-01-01

    Taking tests enhances learning. But what happens when one cannot answer a test question--does an unsuccessful retrieval attempt impede future learning or enhance it? The authors examined this question using materials that ensured that retrieval attempts would be unsuccessful. In Experiments 1 and 2, participants were asked fictional…

  11. Representation of Legal Knowledge for Conceptual Retrieval.

    ERIC Educational Resources Information Center

    Cross, George R.; deBessonet, Cary G.

    1985-01-01

    Describes traditional legal information retrieval systems--Juris, Lexis, Westlaw--and several new rule-based, knowledge-based, legal knowledge reasoning, and analytical legal information systems--Waterman and Peterson's Legal Decisionmaking System, Hafner's Legal Information Retrieval System, McCarty's TAXMAN, and the deBessonet representation of…

  12. Strategic Retrieval in a Reality Monitoring Task

    ERIC Educational Resources Information Center

    Rosburg, Timm; Mecklinger, Axel; Johansson, Mikael

    2011-01-01

    Strategic recollection refers to control processes that allow the retrieval of information that is relevant for a specific situation. These processes can be studied in memory exclusion tasks, which require the retrieval of particular kinds of episodic information. In the current study, we investigated strategic recollection in reality monitoring…

  13. Fuzzy Set Theoretical Approach to Document Retrieval.

    ERIC Educational Resources Information Center

    Radecki, Tadeusz

    1979-01-01

    Presents a new method of document retrieval based on the fundamental operations of fuzzy set theory. Basic notions are introduced. Then the syntax and semantics of the proposed language for document retrieval is given, and an algorithm allocating documents to particular queries is described and its properties are discussed. (Author/CWM)

  14. Attentional Limits in Memory Retrieval--Revisited

    ERIC Educational Resources Information Center

    Green, Collin; Johnston, James C.; Ruthruff, Eric

    2011-01-01

    Carrier and Pashler (1995) concluded--based on locus-of-slack dual-task methodology--that memory retrieval was subject to a central bottleneck. However, this conclusion conflicts with evidence from other lines of research suggesting that memory retrieval proceeds autonomously, in parallel with many other mental processes. In the present…

  15. Chinese Information Retrieval: Using Characters or Words?

    ERIC Educational Resources Information Center

    Nie, Jian-Yun; Ren, Fuji

    1999-01-01

    Discussion of Chinese information retrieval proposes a relaxed segmentation process which extracts the longest words and also the short words implied. Experiments show that information retrieval based on this segmentation gives a slightly higher effectiveness than n-grams or bigrams, and requires less time and space for document and query…

  16. Employing Multiple Representations for Chinese Information Retrieval.

    ERIC Educational Resources Information Center

    Kwok, K. L.

    1999-01-01

    Discusses information retrieval in the Chinese language and describes three representation methods for texts: 1-gram or character, bigram, and short-word. Describes a study that investigated using more than one method simultaneously to improve retrieval effectiveness and considers word segmentation and costs. (Author/LRW)

  17. Enhanced Text Retrieval Using Natural Language Processing.

    ERIC Educational Resources Information Center

    Liddy, Elizabeth D.

    1998-01-01

    Defines natural language processing (NLP); describes the use of NLP in information retrieval (IR); provides seven levels of linguistic analysis: phonological, morphological, lexical, syntactic, semantic, discourse, and pragmatic. Discusses the commercial use of NLP in IR with the example of DR-LINK (Document Retrieval using LINguistic Knowledge)…

  18. Making Space: Automated Storage and Retrieval.

    ERIC Educational Resources Information Center

    Tanis, Norman; Ventuleth, Cindy

    1987-01-01

    Describes a pilot project in automated storage and retrieval of library materials which uses miniload cranes to retrieve bins of materials, and an interface with an online catalog that patrons use to request materials. Savings in space and money and potential problems with the system are discussed. (CLB)

  19. Statistical Inference in Retrieval Effectiveness Evaluation.

    ERIC Educational Resources Information Center

    Savoy, Jacques

    1997-01-01

    Discussion of evaluation methodology in information retrieval focuses on the average precision over a set of fixed recall values in an effort to evaluate the retrieval effectiveness of a search algorithm. Highlights include a review of traditional evaluation methodology with examples; and a statistical inference methodology called bootstrap.…

  20. Advanced Feedback Methods in Information Retrieval.

    ERIC Educational Resources Information Center

    Salton, G.; And Others

    1985-01-01

    In this study, automatic feedback techniques are applied to Boolean query statements in online information retrieval to generate improved query statements based on information contained in previously retrieved documents. Feedback operations are carried out using conventional Boolean logic and extended logic. Experimental output is included to…

  1. Information Retrieval and the Philosophy of Language.

    ERIC Educational Resources Information Center

    Blair, David C.

    2003-01-01

    Provides an overview of some of the main ideas in the philosophy of language that have relevance to the issues of information retrieval, focusing on the description of the intellectual content. Highlights include retrieval problems; recall and precision; words and meanings; context; externalism and the philosophy of language; and scaffolding and…

  2. Validation of MODIS Aerosol Retrieval Over Ocean

    NASA Technical Reports Server (NTRS)

    Remer, Lorraine A.; Tanre, Didier; Kaufman, Yoram J.; Ichoku, Charles; Mattoo, Shana; Levy, Robert; Chu, D. Allen; Holben, Brent N.; Dubovik, Oleg; Ahmad, Ziauddin; Einaudi, Franco (Technical Monitor)

    2001-01-01

    The MODerate resolution Imaging Spectroradiometer (MODIS) algorithm for determining aerosol characteristics over ocean is performing with remarkable accuracy. A two-month data set of MODIS retrievals co-located with observations from the AErosol RObotic NETwork (AERONET) ground-based sunphotometer network provides the necessary validation. Spectral radiation measured by MODIS (in the range 550 - 2100 nm) is used to retrieve the aerosol optical thickness, effective particle radius and ratio between the submicron and micron size particles. MODIS-retrieved aerosol optical thickness at 660 nm and 870 nm fall within the expected uncertainty, with the ensemble average at 660 nm differing by only 2% from the AERONET observations and having virtually no offset. MODIS retrievals of aerosol effective radius agree with AERONET retrievals to within +/- 0.10 micrometers, while MODIS-derived ratios between large and small mode aerosol show definite correlation with ratios derived from AERONET data.

  3. Finding Good Elements for Focused Retrieval

    NASA Astrophysics Data System (ADS)

    Crouch, Carolyn J.; Crouch, Donald B.; Bapat, Salil; Mehta, Sarika; Paranjape, Darshan

    This paper describes the integration of our methodology for the dynamic retrieval of XML elements [2] with traditional article retrieval to facilitate the Focused and the Relevant-in-Context Tasks of the INEX 2008 Ad Hoc Track. The particular problems that arise for dynamic element retrieval in working with text containing both tagged and untagged elements have been solved [3]. The current challenge involves utilizing its ability to produce a rank-ordered list of elements in the context of focused retrieval. Our system is based on the Vector Space Model [8]; basic functions are performed using the Smart experimental retrieval system [7]. Experimental results are reported for the Focused, Relevant-in-Context, and Best-in-Context Tasks of both the 2007 and 2008 INEX Ad Hoc Tracks. These results indicate that the goal of our 2008 investigations—namely, finding good focused elements in the context of the Wikipedia collection-has been achieved.

  4. Compact binary hashing for music retrieval

    NASA Astrophysics Data System (ADS)

    Seo, Jin S.

    2014-03-01

    With the huge volume of music clips available for protection, browsing, and indexing, there is an increased attention to retrieve the information contents of the music archives. Music-similarity computation is an essential building block for browsing, retrieval, and indexing of digital music archives. In practice, as the number of songs available for searching and indexing is increased, so the storage cost in retrieval systems is becoming a serious problem. This paper deals with the storage problem by extending the supervector concept with the binary hashing. We utilize the similarity-preserving binary embedding in generating a hash code from the supervector of each music clip. Especially we compare the performance of the various binary hashing methods for music retrieval tasks on the widely-used genre dataset and the in-house singer dataset. Through the evaluation, we find an effective way of generating hash codes for music similarity estimation which improves the retrieval performance.

  5. Development of concepts for satellite retrieval devices

    NASA Technical Reports Server (NTRS)

    Pruett, E. C.; Robertson, K. B., III; Loughead, T. E.

    1979-01-01

    The teleoperator being developed to augment the Space Transportation System (STS) for satellite placement, retrieval, or servicing at altitudes or orbital planes where it would be impractical to use the shuttle is primarily a general purpose propulsion stage that can be fitted with manipulator arms, automated servicers and satellite retrieval devices for particular missions. Design concepts for a general purpose retrieval device for docking with a satellite to which a grappling fixture has been attached, and for a retrieval device for docking with the Solar Maximum Mission (SMM) spacecraft were defined. The mechanical aspects of these two devices are discussed as well as the crew operations involved and problems created by the requirement for remote control. Drawings for the two retrieval device concepts are included.

  6. Multimodal Feature Integration in the Angular Gyrus during Episodic and Semantic Retrieval

    PubMed Central

    Bonnici, Heidi M.; Richter, Franziska R.; Yazar, Yasemin

    2016-01-01

    Much evidence from distinct lines of investigation indicates the involvement of angular gyrus (AnG) in the retrieval of both episodic and semantic information, but the region's precise function and whether that function differs across episodic and semantic retrieval have yet to be determined. We used univariate and multivariate fMRI analysis methods to examine the role of AnG in multimodal feature integration during episodic and semantic retrieval. Human participants completed episodic and semantic memory tasks involving unimodal (auditory or visual) and multimodal (audio-visual) stimuli. Univariate analyses revealed the recruitment of functionally distinct AnG subregions during the retrieval of episodic and semantic information. Consistent with a role in multimodal feature integration during episodic retrieval, significantly greater AnG activity was observed during retrieval of integrated multimodal episodic memories compared with unimodal episodic memories. Multivariate classification analyses revealed that individual multimodal episodic memories could be differentiated in AnG, with classification accuracy tracking the vividness of participants' reported recollections, whereas distinct unimodal memories were represented in sensory association areas only. In contrast to episodic retrieval, AnG was engaged to a statistically equivalent degree during retrieval of unimodal and multimodal semantic memories, suggesting a distinct role for AnG during semantic retrieval. Modality-specific sensory association areas exhibited corresponding activity during both episodic and semantic retrieval, which mirrored the functional specialization of these regions during perception. The results offer new insights into the integrative processes subserved by AnG and its contribution to our subjective experience of remembering. SIGNIFICANCE STATEMENT Using univariate and multivariate fMRI analyses, we provide evidence that functionally distinct subregions of angular gyrus (An

  7. Comprehension of Linguistic Dependencies: Speed-Accuracy Tradeoff Evidence for Direct-Access Retrieval From Memory

    PubMed Central

    Foraker, Stephani; McElree, Brian

    2012-01-01

    Comprehenders can rapidly and efficiently interpret expressions with various types of non-adjacent dependencies. In the sentence The boy that the teacher warned fell, boy is readily interpreted as the subject of the verb fall despite the fact that a relative clause, that the teacher warned, intervenes between the two dependent elements. We review research investigating three memory operations proposed for resolving this and other types of non-adjacent dependencies: serial search retrieval, in which the dependent constituent is recovered by a search process through representations in memory, direct-access retrieval in which the dependent constituent is recovered directly by retrieval cue operations without search, and active maintenance of the dependent constituent in focal attention. Studies using speed-accuracy tradeoff methodology to examine the full timecourse of interpreting a wide range of non-adjacent dependencies indicate that comprehenders retrieve dependent constituents with a direct-access operation, consistent with the claim that representations formed during comprehension are accessed with a cue-driven, content-addressable retrieval process. The observed timecourse profiles are inconsistent with a broad class of models based on several search operations for retrieval. The profiles are also inconsistent with active maintenance of a constituent while concurrently processing subsequent material, and suggest that, with few exceptions, direct-access retrieval is required to process non-adjacent dependencies. PMID:22448181

  8. Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

    PubMed

    Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

    2016-05-01

    Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress

  9. Below the Surface: Analogical Similarity and Retrieval Competition in Reminding.

    ERIC Educational Resources Information Center

    Wharton, Charles M.; And Others

    1994-01-01

    Three experiments involving 222 undergraduates investigated whether and when human memory retrieval is influenced by structural consistency. In all experiments, retrieval competition was manipulated. Results indicate that both retrieval competition and structural consistency influence reminding. Implications for psychological and artificial…

  10. Dynamics, control and sensor issues pertinent to robotic hands for the EVA retriever system

    NASA Technical Reports Server (NTRS)

    Mclauchlan, Robert A.

    1987-01-01

    Basic dynamics, sensor, control, and related artificial intelligence issues pertinent to smart robotic hands for the Extra Vehicular Activity (EVA) Retriever system are summarized and discussed. These smart hands are to be used as end effectors on arms attached to manned maneuvering units (MMU). The Retriever robotic systems comprised of MMU, arm and smart hands, are being developed to aid crewmen in the performance of routine EVA tasks including tool and object retrieval. The ultimate goal is to enhance the effectiveness of EVA crewmen.

  11. Paraparesis in a Golden Retriever.

    PubMed

    Aschenbroich, S; Woolcock, A; Rissi, D R

    2014-09-01

    A 7-year-old female spayed Golden Retriever dog presented with fever and a 10-day history of neurological signs, including ambulatory paraparesis and pelvic limb ataxia. Neurological examination initially revealed a T3-L3 myelopathy. Thoracic radiographs revealed a diffuse miliary pulmonary pattern. Endotracheal washes and fine-needle aspirates from several organs aimed at identifying a potential infectious agent or neoplastic process were all unsuccessful. Due to worsening of the clinical signs, euthanasia was elected. Necropsy findings included multifocal, pale to dark red, firm nodules infiltrating the lungs, heart, mesentery, pancreas, small intestine, brain, and spinal cord. Cytological examination of impression smears obtained from the pulmonary nodules during necropsy revealed clusters of epithelioid cells admixed with fewer spindle cells, erythrocytes, and scattered leukocytes. Clinical signs and cytological findings initially suggested the possibility of a widespread granulomatous disease or a metastatic epithelial neoplasm as possible clinical differentials in this case. The final diagnosis was based on the gross and histological findings, with confirmation following histochemistry and immunohistochemistry. PMID:24193142

  12. Multilingual retrieval of radiology images.

    PubMed

    Kahn, Charles E

    2009-01-01

    The multilingual search engine ARRS GoldMiner Global was created to facilitate broad international access to a richly indexed collection of more than 200,000 radiologic images. Images are indexed according to key-words and medical concepts that appear in the unstructured text of their English-language image captions. GoldMiner Global exploits the Unicode standard, which allows the accurate representation of characters and ideographs from virtually any language and which supports both left-to-right and right-to-left text directions. The user interface supports queries in Arabic, Chinese, French, German, Italian, Japanese, Korean, Portuguese, Russian, or Spanish. GoldMiner Global incorporates an interface to the United States National Library of Medicine that translates queries into English-language Medical Subject Headings (MeSH) terms. The translated MeSH terms are then used to search the image index and retrieve relevant images. Explanatory text, pull-down menu choices, and navigational guides are displayed in the selected language; search results are displayed in English. GoldMiner Global is freely available on the World Wide Web. PMID:19019997

  13. Tag Completion for Image Retrieval.

    PubMed

    Wu, Lei; Jin, Rong; Jain, Anil K

    2013-03-01

    Many social image search engines are based on keyword/tag matching. This is because tag-based image retrieval (TBIR) is not only efficient but also effective. The performance of TBIR is highly dependent on the availability and quality of manual tags. Recent studies have shown that manual tags are often unreliable and inconsistent. In addition, since many users tend to choose general and ambiguous tags in order to minimize their efforts in choosing appropriate words, tags that are specific to the visual content of images tend to be missing or noisy, leading to a limited performance of TBIR. To address this challenge, we study the problem of tag completion, where the goal is to automatically fill in the missing tags as well as correct noisy tags for given images. We represent the image-tag relation by a tag matrix, and search for the optimal tag matrix consistent with both the observed tags and the visual similarity. We propose a new algorithm for solving this optimization problem. Extensive empirical studies show that the proposed algorithm is significantly more effective than the state-of-the-art algorithms. Our studies also verify that the proposed algorithm is computationally efficient and scales well to large databases. PMID:22641703

  14. Hypermnesia and total retrieval time.

    PubMed

    Mulligan, Neil W

    2006-05-01

    Recall performance sometimes improves over repeated recall attempts, a phenomenon dubbed hypermnesia. A critical theoretical issue is whether hypermnesia is due to repeated testing per se or increased retrieval time. The present experiments investigated by contrasting five testing conditions. All participants were presented with the same study list followed by either two shorter recall tests or a single longer test. In the multiple test conditions, the tests were either separated by a (filled) 7-minute interval (the multiple-split condition), or presented consecutively, with no break (the multiple-immediate condition). In the single test conditions, the test either began at the start of the recall session, after a (filled) 7-minute delay, or with a 7-minute interruption inserted in the middle. The multiple-split condition produced more reminiscence and hypermnesia than the multiple-immediate condition. More importantly, the multiple-split condition produced greater cumulative recall than any of the other conditions (which did not differ among themselves). That is, single and repeated recall tests of equal total duration are not functionally equivalent. PMID:16766451

  15. Data storage and retrieval system

    NASA Technical Reports Server (NTRS)

    Nakamoto, Glen

    1992-01-01

    The Data Storage and Retrieval System (DSRS) consists of off-the-shelf system components integrated as a file server supporting very large files. These files are on the order of one gigabyte of data per file, although smaller files on the order of one megabyte can be accommodated as well. For instance, one gigabyte of data occupies approximately six 9-track tape reels (recorded at 6250 bpi). Due to this large volume of media, it was desirable to 'shrink' the size of the proposed media to a single portable cassette. In addition to large size, a key requirement was that the data needs to be transferred to a (VME based) workstation at very high data rates. One gigabyte (GB) of data needed to be transferred from an archiveable media on a file server to a workstation in less than 5 minutes. Equivalent size, on-line data needed to be transferred in less than 3 minutes. These requirements imply effective transfer rates on the order of four to eight megabytes per second (4-8 MB/s). The DSRS also needed to be able to send and receive data from a variety of other sources accessible from an Ethernet local area network.

  16. Data storage and retrieval system

    NASA Technical Reports Server (NTRS)

    Nakamoto, Glen

    1991-01-01

    The Data Storage and Retrieval System (DSRS) consists of off-the-shelf system components integrated as a file server supporting very large files. These files are on the order of one gigabyte of data per file, although smaller files on the order of one megabyte can be accommodated as well. For instance, one gigabyte of data occupies approximately six 9 track tape reels (recorded at 6250 bpi). Due to this large volume of media, it was desirable to shrink the size of the proposed media to a single portable cassette. In addition to large size, a key requirement was that the data needs to be transferred to a (VME based) workstation at very high data rates. One gigabyte (GB) of data needed to be transferred from an archiveable media on a file server to a workstation in less than 5 minutes. Equivalent size, on-line data needed to be transferred in less than 3 minutes. These requirements imply effective transfer rates on the order of four to eight megabytes per second (4-8 MB/s). The DSRS also needed to be able to send and receive data from a variety of other sources accessible from an Ethernet local area network.

  17. Retrieved Latent Heating from TRMM

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Smith, Eric A.; Houze Jr, Robert

    2008-01-01

    The global hydrological cycle is central to the Earth's climate system, with rainfall and the physics of precipitation formation acting as the key links in the cycle. Two-thirds of global rainfall occurs in the tropics with the associated latent heating (LH) accounting for three-fourths of the total heat energy available to the Earth's atmosphere. In addition, fresh water provided by tropical rainfall and its variability exerts a large impact upon the structure and motions of the upper ocean layer. In the last decade, it has been established that standard products of LH from satellite measurements, particularly TRMM measurements, would be a valuable resource for scientific research and applications. Such products would enable new insights and investigations concerning the complexities of convection system life cycles, the diabatic heating controls and feedbacks related to meso-synoptic circulations and their forecasting, the relationship of tropical patterns of LH to the global circulation and climate, and strategies for improving cloud parameterizations in environmental prediction models. The status of retrieved TRMM LH products, TRMM LH inter-comparison and validation project, current TRMM LH applications and critic issues/action items (based on previous five TRMM LH workshops) is presented in this article.

  18. Spaced retrieval treatment of anomia

    PubMed Central

    Fridriksson, Julius; Holland, Audrey L.; Beeson, Pélagie; Morrow, Leigh

    2006-01-01

    Background Spaced Retrieval (SR) is a treatment approach developed to facilitate recall of information by individuals with dementia. Essentially an errorless learning procedure that can be used to facilitate recall of a variety of information, SR gradually increases the interval between correct recall of target items. Aims Given the success of using SR in dementia, the purpose of this study was to explore its usefulness in improving naming by individuals with aphasia. The rate of acquisition and retention of items was compared between SR and a more traditional treatment technique—cueing hierarchy (CH). Also, each oral naming treatment was run concurrently with a single word writing treatment. Methods & Procedures Three participants who had moderate or severe naming impairments and agraphia were studied. Single-subject design was applied across oral and written naming and treated and untreated items. Outcomes & Results The results indicate that for these participants, SR resulted in improved naming of specific items. The data further suggest that SR compared favourably to CH with regard to both acquisition and retention of items. The participants also benefited nicely from the writing treatment. Conclusions These findings suggest SR may be an alternative for managing naming impairment resulting from aphasia. Furthermore, the study supports providing treatments aimed at two different modalities concurrently. PMID:16823467

  19. Inhibition of protein synthesis or mTOR in the basolateral amygdala blocks retrieval-induced memory strengthening.

    PubMed

    Pedroso, Thiago R; Jobim, Paulo F C; Carvalho, Leonardo M; Christoff, Raissa R; Maurmann, Natasha; Reolon, Gustavo K; Werenicz, Aline; Roesler, Rafael

    2013-11-01

    Fear memory retrieval can lead to either reconsolidation (accompanied or not by strengthening of the memory trace) or extinction. Here, we show that non-reinforced retrieval of inhibitory avoidance (IA) conditioning can induce memory strengthening assessed in a subsequent retention test trial. Infusion of the protein synthesis inhibitor cycloheximide or the mTOR inhibitor rapamycin into the rat basolateral complex of the amygdala (BLA) after a reactivation (retrieval) session impaired retrieval-induced strengthening. Intra-BLA infusion of the mRNA synthesis inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) after retrieval had no effect. These findings provide the first evidence suggesting that non-reinforced IA retrieval can lead to memory strengthening through a mechanism dependent on protein synthesis and mTOR activity in the BLA. PMID:23649124

  20. Subsurface Images Retrieved From Ambient Noise Using Seismic Interferometry

    NASA Astrophysics Data System (ADS)

    Draganov, D.; Campman, X.; Thorbecke, J.; Verdel, A.; Wapenaar, K.

    2009-05-01

    velocity information of the subsurface and enhance reflection arrivals. The end result of the processing consists of stacked time-migrated subsurface sections showing the subsurface structures. Our results exhibit several laterally coherent events. We compare these sections to sections obtained from an active seismic reflection survey along the same lines. The comparison shows that several shallow marker events have been adequately reconstructed from the noise. Having confirmed that the coherent events are subsurface reflectors, we use the retrieved common-shot gathers in a more advanced processing step, so-called prestack depth migration. In this processing we use a constant-gradient subsurface velocity model, which is based on the velocities that we estimated from the retrieved common-shot gathers. The end result is an image of subsurface volume below the survey lines.

  1. Glyoxal retrieval from the Ozone Monitoring Instrument

    NASA Astrophysics Data System (ADS)

    Miller, C. C.; Abad, G. G.; Wang, H.; Liu, X.; Kurosu, T.; Jacob, D. J.; Chance, K.

    2014-06-01

    We present an algorithm for the retrieval of glyoxal from backscattered solar radiation, and apply it to spectra measured by the Ozone Monitoring Instrument (OMI). The algorithm is based on direct spectrum fitting, and adopts a two-step fitting routine to account for liquid water absorption. Previous studies have shown that glyoxal retrieval algorithms are highly sensitive to the position of the spectral fit window. This dependence was systematically tested on real and simulated OMI spectra. We find that a combination of errors resulting from uncertainties in reference cross sections and spectral features associated with the Ring effect are consistent with the fit-window dependence observed in real spectra. This implies an optimal fitting window of 435-461 nm, consistent with previous satellite glyoxal retrievals. The results from the retrieval of simulated spectra also support previous findings that have suggested that glyoxal is sensitive to NO2 cross section temperature. The retrieval window limits of the liquid water retrieval are also tested. A retrieval window 385-470 nm reduces interference with strong spectral features associated with sand. We show that cross track dependent offsets (stripes) present in OMI can be corrected using offsets derived from retrieved slant columns over the Sahara, and apply the correction to OMI data. Average glyoxal columns are on average lower than those of previous studies likely owing to the choice of reference sector for offset correction. OMI VCDs are lower compared to other satellites over the tropics and Asia during the monsoon season, suggesting that the new retrieval is less sensitive to water vapor abundance. Consequently we do not see significant glyoxal enhancements over tropical oceans. OMI derived glyoxal-to-formaldehyde ratios over biogenic and anthropogenic source regions are consistent with surface observations.

  2. Query Specific Rank Fusion for Image Retrieval.

    PubMed

    Zhang, Shaoting; Yang, Ming; Cour, Timothee; Yu, Kai; Metaxas, Dimitris N

    2015-04-01

    Recently two lines of image retrieval algorithms demonstrate excellent scalability: 1) local features indexed by a vocabulary tree, and 2) holistic features indexed by compact hashing codes. Although both of them are able to search visually similar images effectively, their retrieval precision may vary dramatically among queries. Therefore, combining these two types of methods is expected to further enhance the retrieval precision. However, the feature characteristics and the algorithmic procedures of these methods are dramatically different, which is very challenging for the feature-level fusion. This motivates us to investigate how to fuse the ordered retrieval sets, i.e., the ranks of images, given by multiple retrieval methods, to boost the retrieval precision without sacrificing their scalability. In this paper, we model retrieval ranks as graphs of candidate images and propose a graph-based query specific fusion approach, where multiple graphs are merged and reranked by conducting a link analysis on a fused graph. The retrieval quality of an individual method is measured on-the-fly by assessing the consistency of the top candidates' nearest neighborhoods. Hence, it is capable of adaptively integrating the strengths of the retrieval methods using local or holistic features for different query images. This proposed method does not need any supervision, has few parameters, and is easy to implement. Extensive and thorough experiments have been conducted on four public datasets, i.e., the UKbench, Corel-5K, Holidays and the large-scale San Francisco Landmarks datasets. Our proposed method has achieved very competitive performance, including state-of-the-art results on several data sets, e.g., the N-S score 3.83 for UKbench. PMID:26353295

  3. Glyoxal retrieval from the Ozone Monitoring Instrument

    NASA Astrophysics Data System (ADS)

    Miller, C. Chan; Gonzalez Abad, G.; Wang, H.; Liu, X.; Kurosu, T.; Jacob, D. J.; Chance, K.

    2014-11-01

    We present an algorithm for the retrieval of glyoxal from backscattered solar radiation, and apply it to spectra measured by the Ozone Monitoring Instrument (OMI). The algorithm is based on direct spectrum fitting, and adopts a two-step fitting routine to account for liquid water absorption. Previous studies have shown that glyoxal retrieval algorithms are highly sensitive to the position of the spectral fit window. This dependence was systematically tested on real and simulated OMI spectra. We find that a combination of errors resulting from uncertainties in reference cross sections and spectral features associated with the Ring effect are consistent with the fit-window dependence observed in real spectra. This implies an optimal fitting window of 435-461 nm, consistent with previous satellite glyoxal retrievals. The results from the retrieval of simulated spectra also support previous findings that have suggested that glyoxal is sensitive to NO2 cross-section temperature. The retrieval window limits of the liquid water retrieval are also tested. A retrieval window 385-470 nm reduces interference with strong spectral features associated with sand. We show that cross-track dependent offsets (stripes) present in OMI can be corrected using offsets derived from retrieved slant columns over the Sahara, and apply the correction to OMI data. Average glyoxal columns are on average lower than those of previous studies likely owing to the choice of reference sector for offset correction. OMI VCDs (vertical column densities)are lower compared to other satellites over the tropics and Asia during the monsoon season, suggesting that the new retrieval is less sensitive to water vapour abundance. Consequently we do not see significant glyoxal enhancements over tropical oceans. OMI-derived glyoxal-to-formaldehyde ratios over biogenic and anthropogenic source regions are consistent with surface observations.

  4. Practice of information retrieval technique and limitation of database usage (2) - Limitation of retrieval and retrieval by information broker -

    NASA Astrophysics Data System (ADS)

    Suzuki, Shigekazu

    Nowadays everyone can enjoy an information retrieval, thanks for the advancement of computer usage in searching the literatures of science and technology. Regarding limitation for database usage in these days, the author divided searchers into four generations according to their skillful degree for the retrieval technics. In this paper, the author considered a blind spot from the view point of retrieval by searcher after the third generation, who started to have a suspicion to the content of database and emphasised the following three blind spots that we cannot aford to overlook, 1) limitation on input to database, 2) limitation of keyword and code search computer searching, 3) limitation on fitness evaluation of retrieved results.

  5. Integrating retrieved cloud information with model simulation to extend usability of tracer gas retrievals.

    NASA Astrophysics Data System (ADS)

    Tan, Q.; Prinn, R.

    2007-12-01

    We have explored the possibility of using retrieved cloud information to extend the usability of trace gas concentration retrievals from satellites, since choosing only cloud-free retrievals might lead to a bias in their source-sink estimates using inverse modeling, i.e. the geographic locations of cloud-free or cloudy regions and trace gas source or sink regions might be correlated. We used methane retrievals (IMAP) and cloud retrievals (FRESCO) from SCIAMACHY as an example for this study, and assumed agreement between 3D model simulations (MATCH) and cloud-free satellite retrievals as a proxy for defining usability of satellite data. We found that when the pixel is very cloudy (f>0.7), the model simulation, which is integrated with retrieved cloud top height and cloud fraction data, yields similar agreement with observations as obtained with cloud-free pixels (f=0). The addition of cloudy pixel data significantly extends the spatial and temporal coverage of methane retrievals that can be used in source and sink studies. We also tried to overlay the MODIS aerosol retrievals with SCIAMACHY methane data to test the impact of aerosols on trace gas retrievals. Since these two retrievals are somewhat orthogonal, i.e. stronger MODIS aerosol signals over the ocean, and stronger SCIAMACHY methane signals over the land, we have not found a significant correlation between these two retrievals. Other possible reasons for this result could be the different passing times of the two satellites and the wave length differences of the two retrievals.

  6. Photogrammetric Retrieval of Etna's Plume Height from SEVIRI and MODIS

    NASA Astrophysics Data System (ADS)

    Zaksek, K.; Ganci, G.; Hort, M. K.

    2013-12-01

    Even remote volcanoes can impact the modern society due to volcanic ash dispersion in the atmosphere. A lot of research is currently dedicated to minimizing the impact of volcanic ash on air traffic. But the ash transport in the atmosphere and its deposition on land and in the oceans may also significantly influence the climate through modifications of atmospheric CO2. The emphasis of this contribution is the retrieval of volcanic ash plume height. This is important information for air traffic, to predict ash transport and to estimate the mass flux of the ejected material. The best way to monitor volcanic ash cloud top height (ACTH) on the global level is using satellite remote sensing. The most commonly used method for satellite ACTH compares brightness temperature of the cloud with the atmospheric temperature profile. Because of well-known uncertainties of this method we propose photogrammetric methods based on the parallax between data retrieved from geostationary (SEVIRI, HRV band; 1000 m spatial resolution) and polar orbiting satellites (MODIS, band 1; 250 m spatial resolution). The procedure works well if the data from both satellites are retrieved nearly simultaneously butMODIS does not retrieve the data at exactly the same time as SEVIRI. To compensate for advection in the atmosphere we use two sequential SEVIRI images (one before and one after the MODIS retrieval) and interpolate the cloud position from SEVIRI data to the time of MODIS retrieval. ACTH is then estimated by intersection of corresponding lines-of-view from MODIS and interpolated SEVIRI data. The proposed method has already been tested for the case of the Eyjafjallajökull eruption in April 2010. This case study had almost perfect conditions as the plume was vast and stretching over a homogeneous background - ocean. Here we show results of ACTH estimation during lava fountaining activity of Mount Etna in years 2011-2013. This activity resulted in volcanic ash plumes that are much smaller than

  7. Working Memory Retrieval: Contributions of the Left Prefrontal Cortex, the Left Posterior Parietal Cortex, and the Hippocampus

    ERIC Educational Resources Information Center

    Oztekin, Ilke; McElree, Brian; Staresina, Bernhard P.; Davachi, Lila

    2009-01-01

    Functional magnetic resonance imaging was used to identify regions involved in working memory (WM) retrieval. Neural activation was examined in two WM tasks: an item recognition task, which can be mediated by a direct-access retrieval process, and a judgment of recency task that requires a serial search. Dissociations were found in the activation…

  8. Robust hippocampal responsivity during retrieval of consolidated associative memory

    PubMed Central

    Hattori, Shoai; Chen, Lillian; Weiss, Craig; Disterhoft, John F.

    2014-01-01

    A contentious point in memory research is whether or not the hippocampus plays a time-limited role in the consolidation of declarative memories. A widely held view is that declarative memories are initially encoded in the hippocampus, then transferred to the neocortex for long-term storage. Alternate views argue instead that the hippocampus continues to play a role in remote memory recall. These competing theories are largely based on human amnesic and animal lesion/inactivation studies. However, in vivo electrophysiological evidence supporting these views is scarce. Given that other studies examining the role of the hippocampus in remote memory retrieval using lesion and imaging techniques in human and animal models have provided mixed results, it would be particularly useful to gain insight at the in vivo electrophysiological level. Here we report hippocampal single-neuron and theta activity recorded longitudinally during acquisition and remote retrieval of trace eyeblink conditioning. Results from conditioned rabbits were compared to those obtained from yoked pseudo-conditioned control rabbits. Results reveal continued learning-specific hippocampal activity one month after initial acquisition of the task. Our findings yield insight into the normal physiological responses of the hippocampus during memory processes and provide compelling in vivo electrophysiological evidence that the hippocampus is involved in both acquisition and retrieval of consolidated memories. PMID:25515308

  9. Local structure co-occurrence pattern for image retrieval

    NASA Astrophysics Data System (ADS)

    Zhang, Ke; Zhang, Fan; Lu, Jia; Lu, Yinghua; Kong, Jun; Zhang, Ming

    2016-03-01

    Image description and annotation is an active research topic in content-based image retrieval. How to utilize human visual perception is a key approach to intelligent image feature extraction and representation. This paper has proposed an image feature descriptor called the local structure co-occurrence pattern (LSCP). LSCP extracts the whole visual perception for an image by building a local binary structure, and it is represented by a color-shape co-occurrence matrix which explores the relationship of multivisual feature spaces according to visual attention mechanism. As a result, LSCP not only describes low-level visual features integrated with texture feature, color feature, and shape feature but also bridges high-level semantic comprehension. Extensive experimental results on an image retrieval task on the benchmark datasets, corel-10,000, MIT VisTex, and INRIA Holidays, have demonstrated the usefulness, effectiveness, and robustness of the proposed LSCP.

  10. Accelerated Adaptive MGS Phase Retrieval

    NASA Technical Reports Server (NTRS)

    Lam, Raymond K.; Ohara, Catherine M.; Green, Joseph J.; Bikkannavar, Siddarayappa A.; Basinger, Scott A.; Redding, David C.; Shi, Fang

    2011-01-01

    The Modified Gerchberg-Saxton (MGS) algorithm is an image-based wavefront-sensing method that can turn any science instrument focal plane into a wavefront sensor. MGS characterizes optical systems by estimating the wavefront errors in the exit pupil using only intensity images of a star or other point source of light. This innovative implementation of MGS significantly accelerates the MGS phase retrieval algorithm by using stream-processing hardware on conventional graphics cards. Stream processing is a relatively new, yet powerful, paradigm to allow parallel processing of certain applications that apply single instructions to multiple data (SIMD). These stream processors are designed specifically to support large-scale parallel computing on a single graphics chip. Computationally intensive algorithms, such as the Fast Fourier Transform (FFT), are particularly well suited for this computing environment. This high-speed version of MGS exploits commercially available hardware to accomplish the same objective in a fraction of the original time. The exploit involves performing matrix calculations in nVidia graphic cards. The graphical processor unit (GPU) is hardware that is specialized for computationally intensive, highly parallel computation. From the software perspective, a parallel programming model is used, called CUDA, to transparently scale multicore parallelism in hardware. This technology gives computationally intensive applications access to the processing power of the nVidia GPUs through a C/C++ programming interface. The AAMGS (Accelerated Adaptive MGS) software takes advantage of these advanced technologies, to accelerate the optical phase error characterization. With a single PC that contains four nVidia GTX-280 graphic cards, the new implementation can process four images simultaneously to produce a JWST (James Webb Space Telescope) wavefront measurement 60 times faster than the previous code.

  11. Visual Classifier Training for Text Document Retrieval.

    PubMed

    Heimerl, F; Koch, S; Bosch, H; Ertl, T

    2012-12-01

    Performing exhaustive searches over a large number of text documents can be tedious, since it is very hard to formulate search queries or define filter criteria that capture an analyst's information need adequately. Classification through machine learning has the potential to improve search and filter tasks encompassing either complex or very specific information needs, individually. Unfortunately, analysts who are knowledgeable in their field are typically not machine learning specialists. Most classification methods, however, require a certain expertise regarding their parametrization to achieve good results. Supervised machine learning algorithms, in contrast, rely on labeled data, which can be provided by analysts. However, the effort for labeling can be very high, which shifts the problem from composing complex queries or defining accurate filters to another laborious task, in addition to the need for judging the trained classifier's quality. We therefore compare three approaches for interactive classifier training in a user study. All of the approaches are potential candidates for the integration into a larger retrieval system. They incorporate active learning to various degrees in order to reduce the labeling effort as well as to increase effectiveness. Two of them encompass interactive visualization for letting users explore the status of the classifier in context of the labeled documents, as well as for judging the quality of the classifier in iterative feedback loops. We see our work as a step towards introducing user controlled classification methods in addition to text search and filtering for increasing recall in analytics scenarios involving large corpora. PMID:26357193

  12. Neural encoding and retrieval of sound sequences.

    PubMed

    Rauschecker, Josef P

    2005-12-01

    Although considerable progress has been made recently in our understanding of the coding of complex sounds in the cerebral cortex, the processing and storage of tone sequences is still poorly understood. We have used functional magnetic resonance imaging to identify brain mechanisms involved in the encoding and retrieval of melodies by studying the anticipation of familiar music. The results suggest a specific role for each of the following brain structures: the anterior part of the right superior temporal cortex, the right inferior frontal cortex and anterior insula, the left anterior prefrontal cortex, the lateral cerebellum, and the anterior cingulate. In a separate study, we investigated single-neuron responses in the auditory cortex of awake behaving monkeys to alternating tone sequences that in humans evoke the perception of "streaming." Depending on the frequency separation between the tones, an initial single stream may segregate into two streams after a build-up period of several seconds. The neural responses in the monkeys' primary auditory cortex (A1) mirror the psychophysical time course extremely well, suggesting that habituation within A1 may be one reason for stream segregation. However, the higher auditory and prefrontal areas found to be activated by musical melodies are expected to interact with primary areas in both bottom-up and top-down fashion to bring about the perceptual organization of sound sequences. PMID:16597759

  13. Retrieval-induced forgetting and executive control.

    PubMed

    Román, Patricia; Soriano, M Felipa; Gómez-Ariza, Carlos J; Bajo, M Teresa

    2009-09-01

    Retrieving information from long-term memory can lead people to forget previously irrelevant related information. Some researchers have proposed that this retrieval-induced forgetting (RIF) effect is mediated by inhibitory executive-control mechanisms recruited to overcome interference. We assessed whether inhibition in RIF depends on executive processes. The RIF effect observed in a standard retrieval-practice condition was compared to that observed in two different conditions in which participants had to perform two concurrent updating tasks that demanded executive attention. Whereas the usual RIF effect was observed when retrieval practice was performed singly, no evidence of forgetting was found in the dual-task conditions. Results strongly suggest that inhibition involved in RIF is the result of executive-control processes. PMID:19656337

  14. Generalized tetanus in a Labrador retriever

    PubMed Central

    Sprott, Kerri-Rae

    2008-01-01

    A 10-week-old, intact female, Labrador retriever was presented for progressive extensor rigidity, facial swelling, and difficulty in walking. Generalized tetanus was diagnosed and treated successfully. PMID:19252716

  15. The JPL Library Information Retrieval System

    ERIC Educational Resources Information Center

    Walsh, Josephine

    1975-01-01

    The development, capabilities, and products of the computer-based retrieval system of the Jet Propulsion Laboratory Library are described. The system handles books and documents, produces a book catalog, and provides a machine search capability. (Author)

  16. Passive microwave precipitation mapping and retrieval simulation

    NASA Technical Reports Server (NTRS)

    Skofronick, G. M.; Gasiewski, A. J.

    1992-01-01

    A numerical simulation of the satellite-based multispectral passive microwave mapping and precipitation retrieval process is described. The simulation contains three major components: (1) the forward radiative transfer calculation; (2) the sensor observation simulation; and (3) the precipitation retrieval algorithm. Secondary components include a Karhunen-Loeve transformation module and antenna pattern deconvolution module. The simulation facilitates the investigation of candidate precipitation retrieval algorithms using sub-Nyquist brightness temperature imagery, and the comparison of the relative merits of proposed radiometric systems such as the EOS multispectral imaging microwave radiometer (MIMR), the tropical rainfall measurement mission (TRMM) microwave imager (TRMM TMI), and the geosynchronous satellite sensors. A procedure for retrieving rain rates using a statistical iterative approach is outlined.

  17. Environmental impacts of proposed Monitored Retrievable Storage

    SciTech Connect

    Scharber, Wayne K.; Macintire, H. A.; Davis, Paul E.; Cothron, Terry K.; Stephens, Barry K.; Travis, Norman; Walter, George; Mobley, Mike

    1985-12-17

    This report describes environmental impacts from a proposed monitored retrievable storage facility for spent fuels to be located in Tennessee. Areas investigated include: water supply, ground water, air quality, solid waste management, and health hazards. (CBS)

  18. Content-Based Medical Image Retrieval

    NASA Astrophysics Data System (ADS)

    Müller, Henning; Deserno, Thomas M.

    This chapter details the necessity for alternative access concepts to the currently mainly text-based methods in medical information retrieval. This need is partly due to the large amount of visual data produced, the increasing variety of medical imaging data and changing user patterns. The stored visual data contain large amounts of unused information that, if well exploited, can help diagnosis, teaching and research. The chapter briefly reviews the history of image retrieval and its general methods before technologies that have been developed in the medical domain are focussed. We also discuss evaluation of medical content-based image retrieval (CBIR) systems and conclude with pointing out their strengths, gaps, and further developments. As examples, the MedGIFT project and the Image Retrieval in Medical Applications (IRMA) framework are presented.

  19. Using ontology for domain specific information retrieval

    NASA Astrophysics Data System (ADS)

    Shashirekha, H. L.; Murali, S.; Nagabhushan, P.

    2010-02-01

    This paper presents a system for retrieving information from a domain specific document collection made up of data rich unnatural language text documents. Instead of conventional keyword based retrieval, our system makes use of domain ontology to retrieve the information from a collection of documents. The system addresses the problem of representing unnatural language text documents and constructing a classifier model that helps in the efficient retrieval of relevant information. Query to this system may be either the key phrases in terms of concepts or a domain specific unnatural language text document. The classifier used in this system can also be used to assign multiple labels to the previously unseen text document belonging to the same domain. An empirical evaluation of the system is conducted on the domain of text documents describing the classified matrimonial advertisements to determine its performance.

  20. Information content of ozone retrieval algorithms

    NASA Technical Reports Server (NTRS)

    Rodgers, C.; Bhartia, P. K.; Chu, W. P.; Curran, R.; Deluisi, J.; Gille, J. C.; Hudson, R.; Mateer, C.; Rusch, D.; Thomas, R. J.

    1989-01-01

    The algorithms are characterized that were used for production processing by the major suppliers of ozone data to show quantitatively: how the retrieved profile is related to the actual profile (This characterizes the altitude range and vertical resolution of the data); the nature of systematic errors in the retrieved profiles, including their vertical structure and relation to uncertain instrumental parameters; how trends in the real ozone are reflected in trends in the retrieved ozone profile; and how trends in other quantities (both instrumental and atmospheric) might appear as trends in the ozone profile. No serious deficiencies were found in the algorithms used in generating the major available ozone data sets. As the measurements are all indirect in someway, and the retrieved profiles have different characteristics, data from different instruments are not directly comparable.

  1. Improving case retrieval by remembering questions

    SciTech Connect

    Alterman, R.; Griffin, D.

    1996-12-31

    This paper discusses techniques that improve the performance of a case retrieval system, after it is deployed, as a result of the continued usage of the system, by remembering previous episodes of question answering. The user generates a request for information and the system responds with the retrieval of relevant case(s). A history of such transactional behavior over a given set of data is maintained by the system and used as a foundation for adapting its future retrieval behavior. With each transaction, the system acquires information about the usage of the system that is subsequently used to adjust the behavior of the system. This notion of a case retrieval system draws on a distinction between the system in isolation and the system as it is used for a particular set of cases. It also draws on distinctions between the designed system, the deployed system, and the system that emerges as it is used.

  2. The present status and problems in document retrieval system : document input type retrieval system

    NASA Astrophysics Data System (ADS)

    Inagaki, Hirohito

    The office-automation (OA) made many changes. Many documents were begun to maintained in an electronic filing system. Therefore, it is needed to establish efficient document retrieval system to extract useful information. Current document retrieval systems are using simple word-matching, syntactic-matching, semantic-matching to obtain high retrieval efficiency. On the other hand, the document retrieval systems using special hardware devices, such as ISSP, were developed for aiming high speed retrieval. Since these systems can accept a single sentence or keywords as input, it is difficult to explain searcher's request. We demonstrated document input type retrieval system, which can directly accept document as an input, and can search similar documents from document data-base.

  3. Evaluation of multi-layer cloud property retrievals from optimal estimation and Bayesian retrieval algorithms

    NASA Astrophysics Data System (ADS)

    Ding, Y.; Yang, P.

    2015-12-01

    Three physical and radiative cloud properties, namely, optical thickness (tau), effective diameter (De), and cloud top height(h) can be simultaneously inferred from IR radiances for multi-layer cloud cases. The retrieval algorithm implementation is based on a computationally efficient radiative transfer model and spaceborne measurements of narrowband infrared (IR) radiances at the top of the atmosphere. This study focuses on the evaluation of the retrieval results derived from two different algorithms, optimal estimation (OE) algorithm and Bayesian retrieval algorithm. Both of the two methods are able to offer comprehensive error analysis and quality flags. The evaluation results can potentially useful for retrieving the multi-layer clouds properties, a research subject that receives little attention. This presentation will discuss the pros and cons of retrieving cloud properties from the aforesaid retrieval algorithms.

  4. Gunther Tulip Retrievable Inferior Vena Caval Filters: Indications, Efficacy, Retrieval, and Complications

    SciTech Connect

    Looby, S.; Given, M.F.; Geoghegan, T.; McErlean, A.; Lee, M.J.

    2007-02-15

    Purpose. We evaluated the Gunther Tulip (GT) retrievable inferior vena cava (IVC) filter with regard to indications, filtration efficacy, complications, retrieval window, and use of anticoagulation. Method. A retrospective study was performed of 147 patients (64 men, 83 women; mean age 58.8 years) who underwent retrievable GT filter insertion between 2001 and 2005. The indications for placement included a diagnosis of pulmonary embolism or deep venous thrombosis with a contraindication to anticoagulation (n = 68), pulmonary embolism or deep venous thrombosis while on anticoagulation (n = 49), prophylactic filter placement for high-risk surgical patients with a past history of pulmonary embolism or deep venous thrombosis (n = 20), and a high risk of pulmonary embolism or deep venous thrombosis (n = 10). Forty-nine of the 147 patients did not receive anticoagulation (33.7%) while 96 of 147 patients did, 82 of these receiving warfarin (56.5%), 11 receiving low-molecular weight heparins (7.58%), and 3 receiving antiplatelet agents alone (2.06%). Results. Filter placement was successful in 147 patients (100%). Two patients had two filters inserted. Of the 147 patients, filter deployment was on a permanent basis in 102 and with an intention to retrieve in 45 patients. There were 36 (80%) successful retrievals and 9 (20%) failed retrievals. The mean time to retrieval was 33.6 days. The reasons for failed retrieval included filter struts tightly adherent to the IVC wall (5/9), extreme filter tilt (2/9), and extensive filter thrombus (2/9). Complications included pneumothorax (n = 4), failure of filter expansion (n = 1), and breakthrough pulmonary embolism (n = 1). No IVC thrombotic episodes were recorded. Discussion. The Gunther Tulip retrievable filter can be used as a permanent or a retrievable filter. It is safe and efficacious. GT filters can be safely retrieved at a mean time interval of 33.6 days. The newly developed Celect filter may extend the retrieval interval.

  5. Development and testing of single-shell tank waste retrieval technologies: Milestone M-45-01 summary report

    SciTech Connect

    Shen, E.J.

    1994-08-01

    This report summarizes the activities undertaken to develop single-shell tank (SST) waste retrieval technology and complete scale-model testing. Completion of these activities fulfills the commitment of Milestone M-45-01 of the Hanford Federal Facility Agreement and Consent Order (the Tri-Party Agreement). Initial activities included engineering studies that compiled and evaluated data on all known retrieval technologies. Based on selection criteria incorporating regulatory, safety, and operational issues, several technologies were selected for further evaluation and testing. The testing ranged from small-scale, bench-top evaluations of individual technologies to full-scale integrated tests of multiple subsystems operating concurrently as a system using simulated wastes. The current baseline retrieval method for SSTs is hydraulic sluicing. This method has been used successfully in the past to recover waste from SSTs. Variations of this hydraulic or ``past practice`` sluicing may be used to retrieve the waste from the majority of the SSTs. To minimize the potential for releases to the soil, arm-based retrieval systems may be used to recover waste from tanks that are known or suspected to have leaked. Both hydraulic sluicing and arm-based retrieval will be demonstrated in the first SST. Hydraulic sluicing is expected to retrieve most of the waste, and arm-based retrieval will retrieve wastes that remain after sluicing. Subsequent tanks will be retrieved by either hydraulic sluicing or arm-based methods, but not both. The method will be determined by waste characterization, tank integrity (leak status), and presence of in-tank hardware. Currently, it is assumed that approximately 75% of all SSTs will be retrieved by hydraulic sluicing and the remaining tanks by arm-based methods.

  6. Working memory retrieval as a decision process

    PubMed Central

    Pearson, Benjamin; Raškevičius, Julius; Bays, Paul M.; Pertzov, Yoni; Husain, Masud

    2014-01-01

    Working memory (WM) is a core cognitive process fundamental to human behavior, yet the mechanisms underlying it remain highly controversial. Here we provide a new framework for understanding retrieval of information from WM, conceptualizing it as a decision based on the quality of internal evidence. Recent findings have demonstrated that precision of WM decreases with memory load. If WM retrieval uses a decision process that depends on memory quality, systematic changes in response time distribution should occur as a function of WM precision. We asked participants to view sample arrays and, after a delay, report the direction of change in location or orientation of a probe. As WM precision deteriorated with increasing memory load, retrieval time increased systematically. Crucially, the shape of reaction time distributions was consistent with a linear accumulator decision process. Varying either task relevance of items or maintenance duration influenced memory precision, with corresponding shifts in retrieval time. These results provide strong support for a decision-making account of WM retrieval based on noisy storage of items. Furthermore, they show that encoding, maintenance, and retrieval in WM need not be considered as separate processes, but may instead be conceptually unified as operations on the same noise-limited, neural representation. PMID:24492597

  7. Video indexing and retrieval using MPEG-7

    NASA Astrophysics Data System (ADS)

    Smith, John R.

    2002-12-01

    The ongoing growth in digital video content is increasing the need for efficient and effective systems for video indexing and retrieval. Progress is gated by developments along a number of fronts including development of tools for content annotation, invention of methods for automatic labeling and computer-assisted annotation, investigation of new techniques for indexing and retrieval, and development of standards for interoperation of video indexing and retrieval systems. MPEG-7 addresses the interoperability requirements by providing a metadata system for describing multimedia content using XML. In general, MPEG-7 allows interoperable indexing, searching, and retrieval of video, images, audio, and other forms of multimedia data. More specifically for video, MPEG-7 standardizes a number of content description tools that allow effective indexing and retrieval of video content. These tools include video segment description tools, textual annotation and transcription description tools, feature description tools, and semantics and model description tools. In this paper, we investigate the application of MPEG-7 for indexing and retrieval of video content and give examples of MPEG-7 video descriptions.

  8. Operant conditioning of autobiographical memory retrieval.

    PubMed

    Debeer, Elise; Raes, Filip; Williams, J Mark G; Craeynest, Miet; Hermans, Dirk

    2014-01-01

    Functional avoidance is considered as one of the key mechanisms underlying overgeneral autobiographical memory (OGM). According to this view OGM is regarded as a learned cognitive avoidance strategy, based on principles of operant conditioning; i.e., individuals learn to avoid the emotionally painful consequences associated with the retrieval of specific negative memories. The aim of the present study was to test one of the basic assumptions of the functional avoidance account, namely that autobiographical memory retrieval can be brought under operant control. Here 41 students were instructed to retrieve personal memories in response to 60 emotional cue words. Depending on the condition, they were punished with an aversive sound for the retrieval of specific or nonspecific memories in an operant conditioning procedure. Analyzes showed that the course of memory specificity significantly differed between conditions. After the procedure participants punished for nonspecific memories retrieved significantly more specific memories compared to participants punished for specific memories. However, whereas memory specificity significantly increased in participants punished for specific memories, it did not significantly decrease in participants punished for nonspecific memories. Thus, while our findings indicate that autobiographical memory retrieval can be brought under operant control, they do not support a functional avoidance view on OGM. PMID:23445114

  9. Easily retrievable objects among the NEO population

    NASA Astrophysics Data System (ADS)

    García Yárnoz, D.; Sanchez, J. P.; McInnes, C. R.

    2013-08-01

    Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources. The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth's neighbourhood at affordable costs. The asteroid retrieval transfers are sought from the continuum of low energy transfers enabled by the dynamics of invariant manifolds; specifically, the retrieval transfers target planar, vertical Lyapunov and halo orbit families associated with the collinear equilibrium points of the Sun-Earth Circular Restricted Three Body problem. The judicious use of these dynamical features provides the best opportunity to find extremely low energy Earth transfers for asteroid material. A catalogue of asteroid retrieval candidates is then presented. Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of Δ v. Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs.

  10. Retrieval techniques: LVLH and inertially stabilized payloads

    NASA Technical Reports Server (NTRS)

    Yglesias, J. A.

    1980-01-01

    Procedures and techniques are discussed for retrieving payloads that are inertially or local vertical/local horizontal (LVLH) stabilized. Selection of the retrieval profile to be used depends on several factors: (1) control authority of the payload, (2) payload sensitivity to primary reaction control system (PRCS) plumes, (3) whether the payload is inertially or LVLH stabilized, (4) location of the grapple fixture, and (5) orbiter propellant consumption. The general retrieval profiles recommended are a V-bar approach for payloads that are LVLH or gravity-gradient stabilized, and the V-bar approach with one or two phase flyaround for inertially stabilized payloads. Once the general type of profile has been selected, the detailed retrieval profile and timeline should consider the various guidelines, groundrules, and constraints associated with a particular payload or flight. Reaction control system (RCS) propellant requirements for the recommended profiles range from 200 to 1500 pounds, depending on such factors as braking techniques, flyaround maneuvers (if necessary), and stationkeeping operations. The time required to perform a retrieval (starting from 1000 feet) varies from 20 to 130 minutes, depending on the complexity of the profile. The goals of this project are to develop a profile which ensures mission success; to make the retrieval profiles simple; and to keep the pilot workload to a minimum by making use of the automatic features of the orbiter flight software whenever possible.

  11. Neural systems behind word and concept retrieval.

    PubMed

    Damasio, H; Tranel, D; Grabowski, T; Adolphs, R; Damasio, A

    2004-01-01

    Using both the lesion method and functional imaging (positron emission tomography) in large cohorts of subjects investigated with the same experimental tasks, we tested the following hypotheses: (A) that the retrieval of words which denote concrete entities belonging to distinct conceptual categories depends upon partially segregated regions in higher-order cortices of the left temporal lobe; and (B) that the retrieval of conceptual knowledge pertaining to the same concrete entities also depends on partially segregated regions; however, those regions will be different from those postulated in hypothesis A, and located predominantly in the right hemisphere (the second hypothesis tested only with the lesion method). The analyses provide support for hypothesis A in that several regions outside the classical Broca and Wernicke language areas are involved in name retrieval of concrete entities, and that there is a partial segregation in the temporal lobe with respect to the conceptual category to which the entities belong, and partial support for hypothesis B in that retrieval of conceptual knowledge is partially segregated from name retrieval in the lesion study. Those regions identified here are seen as parts of flexible, multi-component systems serving concept and word retrieval for concrete entities belonging to different conceptual categories. By comparing different approaches the article also addresses a number of method issues that have surfaced in recent studies in this field. PMID:15037130

  12. Framing memories: How the retrieval query format shapes the neural bases of remembering.

    PubMed

    Raposo, Ana; Frade, Sofia; Alves, Mara

    2016-08-01

    The way memory questions are framed influences the information that is searched, retrieved, and monitored during remembering. This fMRI study aimed at clarifying how the format of the retrieval query shapes the neural basis of source recollection. During encoding, participants made semantic (pleasantness) or perceptual (number of letters) judgments about words. Subsequently, in a source memory test, the retrieval query was manipulated such that for half of the items from each encoding task, the retrieval query emphasized the semantic source (i.e., semantic query format: "Is this word from the pleasantness task?"), whereas for the other half the retrieval query emphasized the alternate, perceptual source (i.e., perceptual query format: "Is this word from the letter task?"). The results showed that the semantic query format was associated with higher source recognition than the perceptual query format. This behavioral advantage was accompanied by increased activation in several regions associated to controlled semantic elaboration and monitoring of internally-generated features about the past event. In particular, for items semantically encoded, the semantic query, relative to the perceptual query, induced activation in medial prefrontal cortex (PFC), hippocampal, parahippocampal and middle temporal cortex. Conversely, for items perceptually encoded, the semantic query recruited the lateral PFC and occipital-fusiform areas. Interestingly, the semantic format also influenced the processing of new items, eliciting greater L lateral and medial PFC activation. In contrast, the perceptual query format (versus the semantic format) only prompted greater activation in R orbitofrontal cortex and the R inferior parietal lobe, for items encoded in a perceptual manner and for new items, respectively. The results highlight the role of the retrieval query format in source remembering, showing that the retrieval query that emphasizes the semantic source promotes the use of semantic

  13. Retrieval-Based Learning: Positive Effects of Retrieval Practice in Elementary School Children

    PubMed Central

    Karpicke, Jeffrey D.; Blunt, Janell R.; Smith, Megan A.

    2016-01-01

    A wealth of research has demonstrated that practicing retrieval is a powerful way to enhance learning. However, nearly all prior research has examined retrieval practice with college students. Little is known about retrieval practice in children, and even less is known about possible individual differences in retrieval practice. In three experiments, 88 children (mean age 10 years) studied a list of words and either restudied the items or practiced retrieving them. They then took a final free recall test (Experiments 1 and 2) or recognition test (Experiment 3). In all experiments, children showed robust retrieval practice effects. Although a range of individual differences in reading comprehension and processing speed were observed among these children, the benefits of retrieval practice were independent of these factors. The results contribute to the growing body of research supporting the mnemonic benefits of retrieval practice and provide preliminary evidence that practicing retrieval may be an effective learning strategy for children with varying levels of reading comprehension and processing speed. PMID:27014156

  14. Retrieval-Based Learning: Positive Effects of Retrieval Practice in Elementary School Children.

    PubMed

    Karpicke, Jeffrey D; Blunt, Janell R; Smith, Megan A

    2016-01-01

    A wealth of research has demonstrated that practicing retrieval is a powerful way to enhance learning. However, nearly all prior research has examined retrieval practice with college students. Little is known about retrieval practice in children, and even less is known about possible individual differences in retrieval practice. In three experiments, 88 children (mean age 10 years) studied a list of words and either restudied the items or practiced retrieving them. They then took a final free recall test (Experiments 1 and 2) or recognition test (Experiment 3). In all experiments, children showed robust retrieval practice effects. Although a range of individual differences in reading comprehension and processing speed were observed among these children, the benefits of retrieval practice were independent of these factors. The results contribute to the growing body of research supporting the mnemonic benefits of retrieval practice and provide preliminary evidence that practicing retrieval may be an effective learning strategy for children with varying levels of reading comprehension and processing speed. PMID:27014156

  15. Aerosol and cloud retrieval using AATSR

    NASA Astrophysics Data System (ADS)

    Sogacheva, Larisa; Kolmonen, Pekka; Virtanen, Timo; Saponaro, Giulia; Kokhanovsky, Alexander; de Leeuw, Gerrit

    2013-04-01

    Aerosols and clouds play an important role in terrestrial atmospheric dynamics, thermodynamics, chemistry, and radiative transfer and are key elements of the water and energy cycles. Accurate evaluation of the effects of aerosols and clouds on climate requires global information on aerosol properties. Such global information can only be provided using satellite remote sensing. Among the satellite instruments used for aerosol and cloud retrieval is the Advanced Along-Track Scanning Radiometer (AATSR) on board the European Space Agency (ESA) satellite ENVISAT. Many instruments and retrieval techniques have been developed and applied to satellite data to derive cloud data products (Kokhanonsky et al., 2009). However, many problems still remain to be solved. They are mostly related to the usage of homogeneous, single-layered cloud model. Further issues exist for studies of thin clouds, where both cloud inhomogeniety, cloud fraction and the underlying surface bi-directional reflectance must be accounted for in the retrieval process. The aerosol retrieval algorithm (dual-view over land and single-view over ocean) was constructed for ATSR-2 data (e.g. Veefkind et al. 1998). The most recent version of ADV (AATSR Dual View) is described in Kolmenen et al. (2012). The ATSR dual-view allows retrieval without prior information about land surface reflectance. A semi-analytical cloud retrieval algorithm using backscattered radiation in 0.4-2.4 μm spectral region has recently been implemented to ADV for the determination of the optical thickness, the liquid water path, and the effective size of droplets from spectral measurements of the intensity of light reflected from water clouds with large optical thickness. In AacDV (AATSR aerosol and cloud Dual View) aerosol and cloud retrievals are combined. Cloud retrieval starts when cloud tests for aerosol retrieval show the presence of clouds. The algorithm was early introduced in Kokhanovsky et al. (2003). It works well for thick

  16. Developments of global greenhouse gas retrieval algorithm using Aerosol information from GOSAT-CAI

    NASA Astrophysics Data System (ADS)

    Kim, Woogyung; kim, Jhoon; Jung, Yeonjin; lee, Hanlim; Boesch, Hartmut

    2014-05-01

    Human activities have resulted in increasing atmospheric CO2 concentration since the beginning of Industrial Revolution to reaching CO2 concentration over 400 ppm at Mauna Loa observatory for the first time. (IPCC, 2007). However, our current knowledge of carbon cycle is still insufficient due to lack of observations. Satellite measurement is one of the most effective approaches to improve the accuracy of carbon source and sink estimates by monitoring the global CO2 distributions with high spatio-temporal resolutions (Rayner and O'Brien, 2001; Houweling et al., 2004). Currently, GOSAT has provided valuable information to observe global CO2 trend, enables our extended understanding of CO2 and preparation for future satellite plan. However, due to its physical limitation, GOSAT CO2 retrieval results have low spatial resolution and cannot cover wide area. Another obstruction of GOSAT CO2 retrieval is low data availability mainly due to contamination by clouds and aerosols. Especially, in East Asia, one of the most important aerosol source areas, it is hard to have successful retrieval result due to high aerosol concentration. The main purpose of this study is to improve data availability of GOSAT CO2 retrieval. In this study, current state of CO2 retrieval algorithm development is introduced and preliminary results are shown. This algorithm is based on optimal estimation method and utilized VLIDORT the vector discrete ordinate radiative transfer model. This proto type algorithm, developed from various combinations of state vectors to find accurate CO2 concentration, shows reasonable result. Especially the aerosol retrieval algorithm using GOSAT-CAI measurements, which provide aerosol information for the same area with GOSAT-FTS measurements, are utilized as input data of CO2 retrieval. Other CO2 retrieval algorithms use chemical transport model result or climatologically expected values as aerosol information which is the main reason of low data availability. With

  17. Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval

    SciTech Connect

    Yuen, David A.; Onishi, Yasuo; Rustad, James R.; Michener, Thomas E.; Felmy, Andrew R.; Ten, Arkady A.; Hier, Catherine A.

    2000-06-01

    Many highly radioactive wastes will be retrieved by installing mixer pumps that inject high-speed jets to stir up the sludge, saltcake, and supernatant liquid in the tank, blending them into a slurry. This slurry will then be pumped out of the tank into a waste treatment facility. Our objectives are to investigate interactions-chemical reactions, waste rheology, and slurry mixing-occurring during the retrieval operation and to provide a scientific basis for the waste retrieval decision-making process. Specific objectives are to: (1) Evaluate numerical modeling of chemically active, non-Newtonian tank waste mixing, coupled with chemical reactions and realistic rheology; (2) Conduct numerical modeling analysis of local and global mixing of non-Newtonian and Newtonian slurries; and (3) Provide the bases to develop a scientifically justifiable, decision-making support tool for the tank waste retrieval operation.

  18. Abundance retrieval of hydrous minerals around the Mars Science Laboratory landing site in Gale crater, Mars

    NASA Astrophysics Data System (ADS)

    Lin, Honglei; Zhang, Xia; Shuai, Tong; Zhang, Lifu; Sun, Yanli

    2016-02-01

    The detection of hydrous minerals on Mars is of great importance for revealing the early water environment as well as possible biotic activity. However, few studies focus on abundance retrieval of hydrous minerals for some difficulties. In this paper, we studied the area around the Mars Science Laboratory (MSL) landing site, to identify hydrous minerals and retrieve their abundance. Firstly, the distribution of hydrous minerals was extracted using their hydration features. Then, a sparse unmixing algorithm was applied along with the CRISM spectral library to retrieve the abundance of hydrous minerals in this area. As a result, seven hydrous minerals were retrieved, i.e. actinolite, montmorillonite, saponite, jarosite, halloysite, szomolnokite and magnesite and, the total concentration of all hydrous minerals was as high as 40 vol% near the lower reaches of Mount Sharp. Our results were consistent with results from related research and the in-situ analysis of the MSL rover Curiosity.

  19. Overview of the Sixth Text Retrieval Conference (TREC-6).

    ERIC Educational Resources Information Center

    Voorhees, Ellen M.; Harman, Donna

    2000-01-01

    Provides an overview of the Text Retrieval Conference (TREC), a workshop series designed to encourage research on text retrieval for realistic applications by providing large test collections and uniform scoring procedures. Highlights include routing tasks; Chinese language retrieval; cross-language information retrieval; filtering; high…

  20. A prompt information retrieval system on handheld devices

    NASA Astrophysics Data System (ADS)

    Huang, Yo-Ping; Yen, Wei; Lin, Shi-Hung

    2007-04-01

    In this paper, we propose an intelligent bird information retrieval system which aims to construct a mobility-learning activity under the up-to-date wireless technology. The system consists of a Tablet PC and PDAs with wireless networking capabilities. The PDA is equipped with a friendly retrieval interface and a good learning environment. In our system, users only need to click the buttons or input the keywords to retrieve bird information. Besides, users can discuss or share their information and knowledge via the wireless network. Our system saves bird information in four categories including "Introduction," "Images," "Sound," "Streaming Media," and "Ecological Memo." The integral knowledge helps users understand more about birds. Data mining and fuzzy association rules are applied to recommend users those birds they may be interested in. A streaming server on the Tablet PC is built to provide the streaming media for PDA users. By this way, PDA users can enjoy the multimedia from Tablet PC in real time without downloading completely. Finally, the system is a perfect tool for outdoor teaching and can be easily extended to provide navigation and touring services for national parks or museums.

  1. Epsin1 modulates synaptic vesicle retrieval capacity at CNS synapses.

    PubMed

    Kyung, Jae Won; Bae, Jae Ryul; Kim, Dae-Hwan; Song, Woo Keun; Kim, Sung Hyun

    2016-01-01

    Synaptic vesicle retrieval is an essential process for continuous maintenance of neural information flow after synaptic transmission. Epsin1, originally identified as an EPS15-interacting protein, is a major component of clathrin-mediated endocytosis. However, the role of Epsin1 in synaptic vesicle endocytosis at CNS synapses remains elusive. Here, we showed significantly altered synaptic vesicle endocytosis in neurons transfected with shRNA targeting Epsin1 during/after neural activity. Endocytosis was effectively restored by introducing shRNA-insensitive Epsin1 into Epsin1-depleted neurons. Domain studies performed on neurons in which domain deletion mutants of Epsin1 were introduced after Epsin1 knockdown revealed that ENTH, CLAP, and NPFs are essential for synaptic vesicle endocytosis, whereas UIMs are not. Strikingly, the efficacy of the rate of synaptic vesicle retrieval (the "endocytic capacity") was significantly decreased in the absence of Epsin1. Thus, Epsin1 is required for proper synaptic vesicle retrieval and modulates the endocytic capacity of synaptic vesicles. PMID:27557559

  2. Epsin1 modulates synaptic vesicle retrieval capacity at CNS synapses

    PubMed Central

    Kyung, Jae Won; Bae, Jae Ryul; Kim, Dae-Hwan; Song, Woo Keun; Kim, Sung Hyun

    2016-01-01

    Synaptic vesicle retrieval is an essential process for continuous maintenance of neural information flow after synaptic transmission. Epsin1, originally identified as an EPS15-interacting protein, is a major component of clathrin-mediated endocytosis. However, the role of Epsin1 in synaptic vesicle endocytosis at CNS synapses remains elusive. Here, we showed significantly altered synaptic vesicle endocytosis in neurons transfected with shRNA targeting Epsin1 during/after neural activity. Endocytosis was effectively restored by introducing shRNA-insensitive Epsin1 into Epsin1-depleted neurons. Domain studies performed on neurons in which domain deletion mutants of Epsin1 were introduced after Epsin1 knockdown revealed that ENTH, CLAP, and NPFs are essential for synaptic vesicle endocytosis, whereas UIMs are not. Strikingly, the efficacy of the rate of synaptic vesicle retrieval (the “endocytic capacity”) was significantly decreased in the absence of Epsin1. Thus, Epsin1 is required for proper synaptic vesicle retrieval and modulates the endocytic capacity of synaptic vesicles. PMID:27557559

  3. A Retrieval System for Radioactive Target Materials at the NIF

    NASA Astrophysics Data System (ADS)

    Krieger, M.; Shibata, K.; Fallica, J.; Henchen, R.; Pogozelski, E.; Padalino, S.; Sangster, T. C.; Suny Collaboration; Laboratory Collaboration

    2011-10-01

    Currently, solid radioactive material collection from the NIF target chamber is performed via the DIM. The retrieval process takes several hours to complete. To decrease this time for short lived radioisotopes, the Target Materials Retrieval System (TMRS) is being designed to move a radioactive sample from the target chamber to the counting station in less than 50 seconds, using a closed-loop helium filled RaPToRS system. The TMRS consists of three components: the retrieval apparatus, RaPToRS and the counting station. Starting at 0.5 meters from TCC, the sample will move from the vacuum chamber, travel through 60 meters of 10 centimeter diameter RaPToRS tubes, reaching speeds of 10 m/s. The sample will then arrive at the counting station, where it be robotically placed in front of a gamma ray detector. The use of helium will decrease background gamma radiation produced by activated N2 normally found in a pressurized air system. This work was supported in part by the US Department of Energy through the LLE.

  4. Evaluation of sea surface salinity retrieval from SMAP

    NASA Astrophysics Data System (ADS)

    Lee, Tong; Meissner, Thomas; Wentz, Frank; Lagerloef, Gary

    2016-04-01

    NASA's Soil Moisture Active Passive (SMAP) satellite, launched on January 29, 2015, has been delivering measurements since April 2015. Although SMAP's primary mission objective is to measure soil moisture, its L-band radiometer-radar design that is similar to Aquarius (NASA's ocean salinity measuring satellite that ended its operation in June 2015) provides a potential mean to continue Aquarius' legacy. SMAP's radiometer, designed for land applications, has less precision than its Aquarius counterpart. However, the spatial resolution of SMAP's measurements is better than that of Aquarius by several times. SMAP's radar, which would have provided wind measurements needed to correct for surface roughness effect on SSS retrieval, stopped functioning in July 2015. Despite this, the Aquarius team has used the Aquarius experience to retrieve SSS from SMAP's radiometer measurements using auxiliary wind measurements. This presentation evaluates the fidelity of the SMAP SSS in depicting various oceanographic features from open oceans to coastal regions. A quantitative comparison between SMAP SSS and in-situ Argo float measurements and between SMAP and satellite SSS from Aquarius and SMOS during their overlapping periods will be presented. The evaluation demonstrates the very encouraging SSS retrieval from SMAP, which provides temporal continuity of SSS measurements beyond Aquarius.

  5. Effects of Nepeta menthoides aqueous extract on retention and retrieval of memory in mice.

    PubMed

    Sarahroodi, S; Jafari-Najafi, R; Nasri, S; Rohampour, K; Maleki-Jamshid, A; Esmaeili, S

    2012-11-15

    There are several evidences that plants and vegetables with antioxidant activity can reduce oxidative damages in brain and improve cognitive functions. The aim of this study was evaluation of Nepeta menthoides aqueous extract on memory retention and retrieval of mice by using passive avoidance apparatus. For this purpose, mice were classified, coded, weighted and grouped (n = 8) as follow as: control group (Only electric shock), blank group (electric shock plus normal saline) and test groups (electric shock plus Nepeta menthoides extract by doses: 100, 200, 400 and 800 mg kg(-1), i.p.). Delay time of leaving the platform was measured for retention and retrieval test of memory in all mentioned groups. In retention test, plant extract was administered immediately after receiving electric shock while it was administered 24 h after receiving electric shock in retrieval. The results revealed that Nepeta menthoides aqueous extract significantly (p<0.05) increased memory retention and retrieval. The best response for memory retention and retrieval was achieved with 800 mg kg(-1) of Nepeta extract. In conclusion, enhancement of memory retention and retrieval by Nepeta menthoides could be cause of antioxidant activity of its components such as rosmarinic acid, caffeic acid and phenolic acids. PMID:24261125

  6. Functional anatomy of temporal organisation and domain-specificity of episodic memory retrieval

    PubMed Central

    Kwok, Sze Chai; Shallice, Tim; Macaluso, Emiliano

    2013-01-01

    Episodic memory provides information about the “when” of events as well as “what” and “where” they happened. Using functional imaging, we investigated the domain specificity of retrieval-related processes following encoding of complex, naturalistic events. Subjects watched a 42-min TV episode, and 24 h later, made discriminative choices of scenes from the clip during fMRI. Subjects were presented with two scenes and required to either choose the scene that happened earlier in the film (Temporal), or the scene with a correct spatial arrangement (Spatial), or the scene that had been shown (Object). We identified a retrieval network comprising the precuneus, lateral and dorsal parietal cortex, middle frontal and medial temporal areas. The precuneus and angular gyrus are associated with temporal retrieval, with precuneal activity correlating negatively with temporal distance between two happenings at encoding. A dorsal fronto-parietal network engages during spatial retrieval, while antero-medial temporal regions activate during object-related retrieval. We propose that access to episodic memory traces involves different processes depending on task requirements. These include memory-searching within an organised knowledge structure in the precuneus (Temporal task), online maintenance of spatial information in dorsal fronto-parietal cortices (Spatial task) and combining scene-related spatial and non-spatial information in the hippocampus (Object task). Our findings support the proposal of process-specific dissociations of retrieval. PMID:22877840

  7. Neural processing associated with true and false memory retrieval.

    PubMed

    Okado, Yoko; Stark, Craig

    2003-12-01

    We investigated the neural bases for false memory with fMRI by examining neural activity during retrieval processes that yielded true or false memories. We used a reality monitoring paradigm in which participants saw or imagined pictures of concrete objects. (A subsequent misinformation task was also used to increase false memory rates.) At test, fMRI data were collected as the participants determined whether they had seen or had only imagined the object at study. True memories were of seen pictures accurately endorsed as seen, and for false memories were of imagined pictures falsely endorsed as seen. Three distinct patterns of activity were observed: Left frontal and parietal activity was not different for true and for false memories, whereas activity was greater for true than for false memories in occipital visual regions and posterior portions of the parahippocampal gyrus, and activity was greater for false than for true memories in right anterior cingulate gyrus. Possible interpretations are discussed. PMID:15040552

  8. Prefrontal cortex contributions to episodic retrieval monitoring and evaluation.

    PubMed

    Cruse, Damian; Wilding, Edward L

    2009-11-01

    Although the prefrontal cortex (PFC) plays roles in episodic memory judgments, the specific processes it supports are not understood fully. Event-related potential (ERP) studies of episodic retrieval have revealed an electrophysiological modulation - the right-frontal ERP old/new effect - which is thought to reflect activity in PFC. The functional significance of this old/new effect remains a matter of debate, and this study was designed to test two accounts: (i) that the effect indexes processes linked to the monitoring or evaluation of the products of retrieval in service of task demands, or (ii) that it indexes the number of internal decisions required for a task judgment. Participants studied words in one of two colours. In a subsequent retrieval task, old (studied) and new words were presented in a neutral colour. Participants made initial old/new judgments, along with study colour judgments to words thought to be old. They also indicated their confidence (high/low) in the colour decision. Right-frontal ERP old/new effects were larger for high than for low confidence correct colour judgments, and the magnitude of the right-frontal effect was correlated with the proportions of low confidence judgments that were made. Because the numbers of decisions associated with these response categories are equivalent, these findings do not support a decision-based account of the right-frontal ERP old/new effect. Rather, the correlation between confidence and the magnitude of the effect links it with retrieval monitoring and evaluation processes. PMID:19523968

  9. On-Line Retrieval System Design; Part V of Scientific Report No. ISR-18, Information Storage and Retrieval...

    ERIC Educational Resources Information Center

    Cornell Univ., Ithaca, NY. Dept. of Computer Science.

    On-line retrieval system design is discussed in the two papers which make up Part Five of this report on Salton's Magical Automatic Retriever of Texts (SMART) project report. The first paper: "A Prototype On-Line Document Retrieval System" by D. Williamson and R. Williamson outlines a design for a SMART on-line document retrieval system using…

  10. Challenging Conventional Assumptions of Automated Information Retrieval with Real Users: Boolean Searching and Batch Retrieval Evaluations.

    ERIC Educational Resources Information Center

    Hersh, William; Turpin, Andrew; Price, Susan; Kraemer, Dale; Olson, Daniel; Chan, Benjamin; Sacherek, Lynetta

    2001-01-01

    Describes research conducted at the TREC (Text Retrieval Conference) interactive track that compared Boolean and natural language searching, showing they achieved comparable results; and assessed the validity of batch-oriented retrieval evaluations, showing that the results from batch evaluations were not comparable to those obtained in…

  11. TOFIR: A Tool of Facilitating Information Retrieval - Introduce a Visual Retrieval Model.

    ERIC Educational Resources Information Center

    Zhang, Jin

    2001-01-01

    Introduces a new method for the visualization of information retrieval called TOFIR (Tool of Facilitating Information Retrieval). Discusses the use of angle attributes of a document to construct the angle-based visual space; two-dimensional and three-dimensional visual tools; ambiguity; and future research directions. (Author/LRW)

  12. System engineering approach to GPM retrieval algorithms

    SciTech Connect

    Rose, C. R.; Chandrasekar, V.

    2004-01-01

    System engineering principles and methods are very useful in large-scale complex systems for developing the engineering requirements from end-user needs. Integrating research into system engineering is a challenging task. The proposed Global Precipitation Mission (GPM) satellite will use a dual-wavelength precipitation radar to measure and map global precipitation with unprecedented accuracy, resolution and areal coverage. The satellite vehicle, precipitation radars, retrieval algorithms, and ground validation (GV) functions are all critical subsystems of the overall GPM system and each contributes to the success of the mission. Errors in the radar measurements and models can adversely affect the retrieved output values. Ground validation (GV) systems are intended to provide timely feedback to the satellite and retrieval algorithms based on measured data. These GV sites will consist of radars and DSD measurement systems and also have intrinsic constraints. One of the retrieval algorithms being studied for use with GPM is the dual-wavelength DSD algorithm that does not use the surface reference technique (SRT). The underlying microphysics of precipitation structures and drop-size distributions (DSDs) dictate the types of models and retrieval algorithms that can be used to estimate precipitation. Many types of dual-wavelength algorithms have been studied. Meneghini (2002) analyzed the performance of single-pass dual-wavelength surface-reference-technique (SRT) based algorithms. Mardiana (2003) demonstrated that a dual-wavelength retrieval algorithm could be successfully used without the use of the SRT. It uses an iterative approach based on measured reflectivities at both wavelengths and complex microphysical models to estimate both No and Do at each range bin. More recently, Liao (2004) proposed a solution to the Do ambiguity problem in rain within the dual-wavelength algorithm and showed a possible melting layer model based on stratified spheres. With the No and Do

  13. A semantic based video indexing and retrieval system for maritime surveillance

    NASA Astrophysics Data System (ADS)

    Nguyen, Hieu T.; Ramu, Prakash; Liu, Xiaoqing; Wei, Hai; Yadegar, Jacob

    2009-05-01

    Content-based video retrieval from archived image/video is a very attractive capability of modern intelligent video surveillance systems. This paper presents an innovative Semantic-Based Video Indexing and Retrieval (SBVIR) software toolkit to help users of intelligent video surveillance to easily and rapidly search the content of large video archives to conduct video-based forensic and image intelligence. Tailored for maritime environment, SBVIR is suited for surveillance applications in harbor, sea shores, or around ships. The system comprises two major modules: a video analytic module that performs automatic target detection, tracking, classification, activities recognition, and a retrieval module that performs data indexing, and information retrieval. SBVIR is capable of detecting and tracking objects from multiple cameras robustly in condition of dynamic water background and illumination changes. The system provides hierarchical target classification among a large ontology of watercraft classes, and is capable of recognizing a variety of boat activities. Video retrieval is achieved with both query-by-keyword and query-by-example. Users can query video content using semantic concepts selected from a large dictionary of objects and activities, display the history linked to a given target/activity, and search for anomalies. The user can interact with the system and provide feedbacks to tune the system for improved accuracy and relevance of retrieved data. SBVIR has been tested for real maritime surveillance scenarios and shown to be able to generate highly-semantic metadata tags that can be used during the retrieval to provide user with relevant and accurate data in real-time.

  14. Retrieval plus scanning: does it occur?

    PubMed

    Brannelly, S; Tehan, G; Humphreys, M S

    1989-11-01

    In the two experiments reported here, we tested the retrieval-plus-scan model of delayed probe recognition by adding a second probe 2 sec after subjects had responded to the first probe. According to this model, the list items should still be in consciousness from the first probe at the time of the second probe. Consequently, on tests in which the first probe had been tested immediately, we expected to find the same pattern of performance on both first and second probes. On tests in which the first probe came after a filled delay, we expected the first-probe data to show the effects of retrieval and proactive interference. These effects should not be present on the second probe. The results of the first-probe data in both experiments were consistent with the retrieval-plus-scan model. The second-probe data did not fit the model, however. In the first experiment, the second probe on what had been delayed first-probe trials still produced intercept differences, indicating the presence of retrieval. In the second experiment, the effects of proactive interference were still present on the second probe. It is suggested that these results not only invalidate the retrieval-plus-scan model for delayed probe recognition but that they, along with other results, cast doubt on a scanning operation in immediate probe recognition. PMID:2811668

  15. Ultraspectral Sounding Retrieval Error Budget and Estimation

    NASA Technical Reports Server (NTRS)

    Zhou, Daniel K.; Larar, Allen M.; Liu, Xu; Smith, William L.; Strow, L. Larrabee; Yang, Ping

    2011-01-01

    The ultraspectral infrared radiances obtained from satellite observations provide atmospheric, surface, and/or cloud information. The intent of the measurement of the thermodynamic state is the initialization of weather and climate models. Great effort has been given to retrieving and validating these atmospheric, surface, and/or cloud properties. Error Consistency Analysis Scheme (ECAS), through fast radiative transfer model (RTM) forward and inverse calculations, has been developed to estimate the error budget in terms of absolute and standard deviation of differences in both spectral radiance and retrieved geophysical parameter domains. The retrieval error is assessed through ECAS without assistance of other independent measurements such as radiosonde data. ECAS re-evaluates instrument random noise, and establishes the link between radiometric accuracy and retrieved geophysical parameter accuracy. ECAS can be applied to measurements of any ultraspectral instrument and any retrieval scheme with associated RTM. In this paper, ECAS is described and demonstration is made with the measurements of the METOP-A satellite Infrared Atmospheric Sounding Interferometer (IASI)..

  16. AIRS Retrieval Validation During the EAQUATE

    NASA Technical Reports Server (NTRS)

    Zhou, Daniel K.; Smith, William L.; Cuomo, Vincenzo; Taylor, Jonathan P.; Barnet, Christopher D.; DiGirolamo, Paolo; Pappalardo, Gelsomina; Larar, Allen M.; Liu, Xu; Newman, Stuart M.

    2006-01-01

    Atmospheric and surface thermodynamic parameters retrieved with advanced hyperspectral remote sensors of Earth observing satellites are critical for weather prediction and scientific research. The retrieval algorithms and retrieved parameters from satellite sounders must be validated to demonstrate the capability and accuracy of both observation and data processing systems. The European AQUA Thermodynamic Experiment (EAQUATE) was conducted mainly for validation of the Atmospheric InfraRed Sounder (AIRS) on the AQUA satellite, but also for assessment of validation systems of both ground-based and aircraft-based instruments which will be used for other satellite systems such as the Infrared Atmospheric Sounding Interferometer (IASI) on the European MetOp satellite, the Cross-track Infrared Sounder (CrIS) from the NPOESS Preparatory Project and the following NPOESS series of satellites. Detailed inter-comparisons were conducted and presented using different retrieval methodologies: measurements from airborne ultraspectral Fourier transform spectrometers, aircraft in-situ instruments, dedicated dropsondes and radiosondes, and ground based Raman Lidar, as well as from the European Center for Medium range Weather Forecasting (ECMWF) modeled thermal structures. The results of this study not only illustrate the quality of the measurements and retrieval products but also demonstrate the capability of these validation systems which are put in place to validate current and future hyperspectral sounding instruments and their scientific products.

  17. Web information retrieval based on ontology

    NASA Astrophysics Data System (ADS)

    Zhang, Jian

    2013-03-01

    The purpose of the Information Retrieval (IR) is to find a set of documents that are relevant for a specific information need of a user. Traditional Information Retrieval model commonly used in commercial search engine is based on keyword indexing system and Boolean logic queries. One big drawback of traditional information retrieval is that they typically retrieve information without an explicitly defined domain of interest to the users so that a lot of no relevance information returns to users, which burden the user to pick up useful answer from these no relevance results. In order to tackle this issue, many semantic web information retrieval models have been proposed recently. The main advantage of Semantic Web is to enhance search mechanisms with the use of Ontology's mechanisms. In this paper, we present our approach to personalize web search engine based on ontology. In addition, key techniques are also discussed in our paper. Compared to previous research, our works concentrate on the semantic similarity and the whole process including query submission and information annotation.

  18. Mescalero Apache Tribe Monitored Retrievable Storage (MRS)

    SciTech Connect

    Peso, F.

    1992-03-13

    The Nuclear Waste Policy Act of 1982, as amended, authorizes the siting, construction and operation of a Monitored Retrievable Storage (MRS) facility. The MRS is intended to be used for the temporary storage of spent nuclear fuel from the nation's nuclear power plants beginning as early as 1998. Pursuant to the Nuclear Waste Policy Act, the Office of the Nuclear Waste Negotiator was created. On October 7, 1991, the Nuclear Waste Negotiator invited the governors of states and the Presidents of Indian tribes to apply for government grants in order to conduct a study to assess under what conditions, if any, they might consider hosting an MRS facility. Pursuant to this invitation, on October 11, 1991 the Mescalero Apache Indian Tribe of Mescalero, NM applied for a grant to conduct a phased, preliminary study of the safety, technical, political, environmental, social and economic feasibility of hosting an MRS. The preliminary study included: (1) An investigative education process to facilitate the Tribe's comprehensive understanding of the safety, environmental, technical, social, political, and economic aspects of hosting an MRS, and; (2) The development of an extensive program that is enabling the Tribe, in collaboration with the Negotiator, to reach an informed and carefully researched decision regarding the conditions, (if any), under which further pursuit of the MRS would be considered. The Phase 1 grant application enabled the Tribe to begin the initial activities necessary to determine whether further consideration is warranted for hosting the MRS facility. The Tribe intends to pursue continued study of the MRS in order to meet the following objectives: (1) Continuing the education process towards a comprehensive understanding of the safety, environmental, technical, social and economic aspects of the MRS; (2) Conducting an effective public participation and information program; (3) Participating in MRS meetings.

  19. Retrieving autobiographical memories: How different retrieval strategies associated with different cues explain reaction time differences.

    PubMed

    Uzer, Tugba

    2016-02-01

    Previous research has shown that memories cued by concrete concepts, such as objects, are retrieved faster than those cued by more abstract concepts, such as emotions. This effect has been explained by the fact that more memories are directly retrieved from object versus emotion cues. In the present study, we tested whether RT differences between memories cued by emotion versus object terms occur not only because object cues elicit direct retrieval of more memories (Uzer, Lee, & Brown, 2012), but also because of differences in memory generation in response to emotions versus objects. One hundred university students retrieved memories in response to basic-level (e.g. orange), superordinate-level (e.g. plant), and emotion (e.g. surprised) cues. Retrieval speed was measured and participants reported whether memories were directly retrieved or generated on each trial. Results showed that memories were retrieved faster in response to basic-level versus superordinate-level and emotion cues because a) basic-level cues elicited more directly retrieved memories, and b) generating memories was more difficult when cues were abstract versus concrete. These results suggest that generative retrieval is a cue generation process in which additional cues that provide contextual information including the target event are produced. Memories are retrieved more slowly in response to emotion cues in part because emotion labels are less effective cues of appropriate contextual information. This particular finding is inconsistent with the idea that emotion is a primary organizational unit for autobiographical memories. In contrast, the difficulty of emotional memory generation implies that emotions represent low-level event information in the organization of autobiographical memory. PMID:26802518

  20. Retrieving Similar Styles to Parse Clothing.

    PubMed

    Yamaguchi, Kota; Kiapour, M Hadi; Ortiz, Luis E; Berg, Tamara L

    2015-05-01

    Clothing recognition is a societally and commercially important yet extremely challenging problem due to large variations in clothing appearance, layering, style, and body shape and pose. In this paper, we tackle the clothing parsing problem using a retrieval-based approach. For a query image, we find similar styles from a large database of tagged fashion images and use these examples to recognize clothing items in the query. Our approach combines parsing from: pre-trained global clothing models, local clothing models learned on the fly from retrieved examples, and transferred parse-masks (Paper Doll item transfer) from retrieved examples. We evaluate our approach extensively and show significant improvements over previous state-of-the-art for both localization (clothing parsing given weak supervision in the form of tags) and detection (general clothing parsing). Our experimental results also indicate that the general pose estimation problem can benefit from clothing parsing. PMID:26353326

  1. Simaltaneous Retrieval System for "Kanji" and "Kana"

    NASA Astrophysics Data System (ADS)

    Nakajima, Ayetsu; Matsuda, Masahisa; Kanagawa, Arata

    The ABC News Information Retrieval System was developed by Asahi Broadcasting Corporation and has been in operation since October 1985. The system is designed to give people involved in the News Department easy access to library sources such as news films and video tapes. It has an initial file size of 100,000 items with a monthly update of 900 records. The system also has an interactive free keyword information retrieval system featuring keyword entry in Kanji (Japanese ideographs) for online retrieval in Kanji and Kana (Japanese syllabic symbols). In addition, it employs automatic sampling software enabling relevant keywords to be extracted from the contents of the database. Each record consist of a title, news summary and a description of visual materials, providing content references concerning a certain incident, accident or event which took place, and a brief description of each.

  2. Quantum image with high retrieval performance

    NASA Astrophysics Data System (ADS)

    Ruan, Yue; Chen, Hanwu; Liu, Zhihao; Tan, Jianing

    2016-02-01

    Quantum image retrieval is an exhaustive work due to exponential measurements. Casting aside the background of image processing, quantum image is a pure many-body state, and the retrieval task is a physical process named as quantum state tomography. Tomography of a special class of states, permutationally symmetric states, just needs quadratic measurement scales with the number of qubits. In order to take advantage of this result, we propose a method to map the main energy of the image to these states. First, we deduce that n+1 permutationally symmetric states can be constructed as bases of 2^n Hilbert space ( n qubits) at least. Second, we execute Schmidt decomposition by continually bipartite splitting of the quantum image (state). At last, we select n+1 maximum coefficients, do base transformation to map these coefficients to new bases (permutationally symmetric states). By these means, the quantum image with high retrieval performance can be gotten.

  3. Intentional retrieval suppression can conceal guilty knowledge in ERP memory detection tests.

    PubMed

    Bergström, Zara M; Anderson, Michael C; Buda, Marie; Simons, Jon S; Richardson-Klavehn, Alan

    2013-09-01

    Brain-activity markers of guilty knowledge have been promoted as accurate and reliable measures for establishing criminal culpability. Tests based on these markers interpret the presence or absence of memory-related neural activity as diagnostic of whether or not incriminating information is stored in a suspect's brain. This conclusion critically relies on the untested assumption that reminders of a crime uncontrollably elicit memory-related brain activity. However, recent research indicates that, in some circumstances, humans can control whether they remember a previous experience by intentionally suppressing retrieval. We examined whether people could use retrieval suppression to conceal neural evidence of incriminating memories as indexed by Event-Related Potentials (ERPs). When people were motivated to suppress crime retrieval, their memory-related ERP effects were significantly decreased, allowing guilty individuals to evade detection. Our findings indicate that brain measures of guilty knowledge may be under criminals' intentional control and place limits on their use in legal settings. PMID:23664804

  4. Intentional retrieval suppression can conceal guilty knowledge in ERP memory detection tests☆

    PubMed Central

    Bergström, Zara M.; Anderson, Michael C.; Buda, Marie; Simons, Jon S.; Richardson-Klavehn, Alan

    2013-01-01

    Brain-activity markers of guilty knowledge have been promoted as accurate and reliable measures for establishing criminal culpability. Tests based on these markers interpret the presence or absence of memory-related neural activity as diagnostic of whether or not incriminating information is stored in a suspect's brain. This conclusion critically relies on the untested assumption that reminders of a crime uncontrollably elicit memory-related brain activity. However, recent research indicates that, in some circumstances, humans can control whether they remember a previous experience by intentionally suppressing retrieval. We examined whether people could use retrieval suppression to conceal neural evidence of incriminating memories as indexed by Event-Related Potentials (ERPs). When people were motivated to suppress crime retrieval, their memory-related ERP effects were significantly decreased, allowing guilty individuals to evade detection. Our findings indicate that brain measures of guilty knowledge may be under criminals’ intentional control and place limits on their use in legal settings. PMID:23664804

  5. Evolutionary Computing Methods for Spectral Retrieval

    NASA Technical Reports Server (NTRS)

    Terrile, Richard; Fink, Wolfgang; Huntsberger, Terrance; Lee, Seugwon; Tisdale, Edwin; VonAllmen, Paul; Tinetti, Geivanna

    2009-01-01

    A methodology for processing spectral images to retrieve information on underlying physical, chemical, and/or biological phenomena is based on evolutionary and related computational methods implemented in software. In a typical case, the solution (the information that one seeks to retrieve) consists of parameters of a mathematical model that represents one or more of the phenomena of interest. The methodology was developed for the initial purpose of retrieving the desired information from spectral image data acquired by remote-sensing instruments aimed at planets (including the Earth). Examples of information desired in such applications include trace gas concentrations, temperature profiles, surface types, day/night fractions, cloud/aerosol fractions, seasons, and viewing angles. The methodology is also potentially useful for retrieving information on chemical and/or biological hazards in terrestrial settings. In this methodology, one utilizes an iterative process that minimizes a fitness function indicative of the degree of dissimilarity between observed and synthetic spectral and angular data. The evolutionary computing methods that lie at the heart of this process yield a population of solutions (sets of the desired parameters) within an accuracy represented by a fitness-function value specified by the user. The evolutionary computing methods (ECM) used in this methodology are Genetic Algorithms and Simulated Annealing, both of which are well-established optimization techniques and have also been described in previous NASA Tech Briefs articles. These are embedded in a conceptual framework, represented in the architecture of the implementing software, that enables automatic retrieval of spectral and angular data and analysis of the retrieved solutions for uniqueness.

  6. Nonsurgical retrieval of embolized coronary stents.

    PubMed

    Eggebrecht, H; Haude, M; von Birgelen, C; Oldenburg, O; Baumgart, D; Herrmann, J; Welge, D; Bartel, T; Dagres, N; Erbel, R

    2000-12-01

    Embolization of coronary stents before deployment is a rare but challenging complication of coronary stenting. Different methods for nonsurgical stent retrieval have been suggested. There were 20 cases (0.90%) of intracoronary stent embolization among 2,211 patients who underwent implantation of 4,066 stents. Twelve of 1,147 manually crimped stents (1.04%) and eight of 2,919 premounted stents were lost (0.27%, P < 0.01) during retraction of the delivery system, because the target lesion could not be either reached or crossed. Percutaneous retrieval was successfully carried out in 10 of 14 patients (71%) in whom retrieval was attempted. In 10 patients, stent retrieval was tried with 1.5-mm low-profile angioplasty balloon catheters (success in 7/10) and in seven cases with myocardial biopsy forceps or a gooseneck snare (success in 3/7). Three patients (15%) underwent urgent coronary artery bypass surgery after failed percutaneous retrieval, but their outcomes were fatal. In two patients, stents were compressed against the vessel wall by another stent, without compromising coronary blood flow. In two patients, a stent was lost to the periphery without clinical side effects; treatment was conservative in these cases. Embolization of stents before deployment is a rare but serious complication of coronary stenting, with hazardous potential for the patient. Manual mounting of stents is associated with a significantly higher risk of stent embolization. Stent retrieval from the coronary circulation with low-profile angioplasty balloon catheters is a readily available and technically familiar approach that has a relatively high success rate. PMID:11108675

  7. Integral Monitored Retrievable Storage (MRS) Facility conceptual design report

    SciTech Connect

    1985-09-01

    In April 1985, the Department of Energy (DOE) selected the Clinch River site as its preferred site for the construction and operation of the monitored retrievable storage (MRS) facility (USDOE, 1985). In support of the DOE MRS conceptual design activity, available data describing the site have been gathered and analyzed. A composite geotechnical description of the Clinch River site has been developed and is presented herein. This report presents Clinch River site description data in the following sections: general site description, surface hydrologic characteristics, groundwater characteristics, geologic characteristics, vibratory ground motion, surface faulting, stability of subsurface materials, slope stability, and references. 48 refs., 35 figs., 6 tabs.

  8. Emissivity retrieval from indoor hyperspectral imaging of mineral grains

    NASA Astrophysics Data System (ADS)

    Yousefi, Bardia; Sojasi, Saeed; Ibarra Castanedo, Clemente; Beaudoin, Georges; Huot, François; Maldague, Xavier P. V.; Chamberland, Martin; Lalonde, Erik

    2016-05-01

    The proposed approach addresses the problem of retrieving the emissivity of hyperspectral data in the spectroscopic imageries from indoor experiments. This methodology was tested on experimental data that have been recorded with hyperspectral images working in visible/near infrared and long-wave infrared bands. The proposed technique provides a framework for computing down-welling spectral radiance applying non-negative matrix factorization (NMF) analysis. It provides the necessary means for the non-uniform correction of active thermographical experiments. The obtained results indicate promising accuracy. In addition, the application of the proposed technique is not limited to non-uniform heating spectroscopy but to uniform spectroscopy as well.

  9. Syncom 4 deploy, LDEF retrieval highlight 10-day Columbia flight

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The objectives of Space Shuttle Mission STS-32 are described along with major flight activities, prelaunch and launch operations, trajectory sequence of events, and landing and post-landing operations. The primary objectives of STS-32 are the deployment of a Navy synchronous communications satellite (Syncom 4) and the retrieval of the Long Duration Exposure Facility (LDEF) launched from the Challenger in April 1984. Secondary STS-32 payloads include a protein crystal growth experiment, the Fluids Experiment Apparatus (FEA) for the investigation of microgravity materials processing, the Mesoscale Lighting Experiment, the Latitude-Longitude Locator Experiment, the Americal Flight Echocardiograph, and an experiment to investigate neurospora circadian rhythms in a microgravity environment.

  10. Late arthroscopic retrieval of a bullet from hip joint

    PubMed Central

    Gupta, Ravi K; Aggarwal, Varun

    2009-01-01

    We describe a case of arthroscopic retrieval of a bullet from the hip joint of an 18-year-old boy, who sustained the injury four months back, accidentally, while bird hunting with a country made shotgun. The surgery was performed with the standard ordinary instrumentation of knee arthroscopy. The patient became pain-free the same evening and started partial weight bearing on the next day of surgery. At 13 months follow-up, the patient had returned to normal activity without any functional limitations. PMID:19838396

  11. [Brain Mechanism for Successful Memory Retrieval].

    PubMed

    Takeda, Masaki

    2016-04-01

    Previous neuropsychological studies that investigated patients with brain injury have revealed the presense of multiple memory systems and the related brain regions. Recent functional imaging studies have identified a neuronal network including the temporal cortex and hippocampus that is responsible for the retrieval of semantic memory. This memory network was further investigated by electrophysiology using a simultaneous recording technique. This new technique revealed that a coupling of inter-area top-down signal within the temporal cortex with translaminar signal processing is required for successful memory retrieval of visual objects. PMID:27056865

  12. Retrieval of Aerosol Height with TROPOMI

    NASA Astrophysics Data System (ADS)

    Sanders, A. F. J.; de Haan, J. F.; Veefkind, J. P.

    2012-04-01

    The Tropospheric Monitoring Instrument (TROPOMI), to be launched in 2015, will feature a new aerosol product providing the height of aerosol layers. Aerosol Layer Height will be one of two aerosol products, the other one being the Absorbing Aerosol Index. TROPOMI is a UV-VIS-NIR imaging spectrometer with daily global coverage. It will be part of ESA's Sentinel-5 Precursor mission. Algorithm development for the aerosol height product is currently underway at KNMI. In this presentation we will introduce the algorithm, highlight some of the development issues and discuss possible applications and example aerosol cases. Aerosol height observations from the near-infrared wavelength range will improve retrieval of other aerosol properties, particularly retrieval of absorption optical thickness. An increase in absorption in the ultraviolet wavelength range can be due to a higher imaginary part of the refractive index or to the aerosol layer being at a higher altitude. Independent height observations will therefore further constrain retrieval of the single scattering albedo. Furthermore, aerosol profile information is an important parameter when estimating radiative forcings and climate impacts of aerosol, it is a significant source of uncertainty in trace gas retrieval and it helps in understanding atmospheric transport mechanisms. Finally, timely available, global observations of aerosol height will be of interest to aviation safety agencies. The retrieval algorithm for aerosol height will be based on absorption by oxygen in the A-band (759-770 nm). Aerosols are assumed to be contained in a single layer. A spectral fit of reflectance (resolution 0.5 nm) across the absorption band provides layer height. The retrieval method will be optimal estimation to ensure a proper error analysis. Sensitivity studies have indicated that accuracy and precision of retrieved height for cloud-free scenes will be well below the TROPOMI science requirements (1 km). They have also shown that

  13. Trends in medical information retrieval on Internet.

    PubMed

    Baujard, O; Baujard, V; Aurel, S; Boyer, C; Appel, R D

    1998-09-01

    Information on the World Wide Web is unstructured, distributed, multimedia and multilingual. Many tools have been developed to help users search for useful information: subject hierarchies, general search engines, browsers and search assistants. Although helpful, they present serious limitations, mainly in terms of precision, multilingual indexing and distribution. In this paper, we cover some on-line solutions to medical information discovery and present our own approach, the MARVIN (multi-agent retrieval vagabond on information network) project, which tackles medical information research with specialized cooperative retrieval agents. We also draw some outlines for future extensions. PMID:9861514

  14. Practical video indexing and retrieval system

    NASA Astrophysics Data System (ADS)

    Liang, Yiqing; Wolf, Wayne H.; Liu, Bede; Huang, Jeffrey R.

    1998-03-01

    We integrated a practical digital video database system based on language and image analysis with components from digital video processing, still image search, information retrieval, closed captioning processing. The attempt is to utilize the multiple modalities of information in video and implement data fusion among the multiple modalities; image information, speech/dialog information, closed captioning information, sound track information such as music, gunfire, explosion, caption information, motion information, temporal information. Effort is made to allow access video contents at different levels including video program level, scene level, shot level, and object level. Approaches of browsing, subject-based classification, and random retrieving are available to gain access to the contents.

  15. Optimal Aerosol Parameterization for Remote Sensing Retrievals

    NASA Technical Reports Server (NTRS)

    Newchurch, Michael J.

    2004-01-01

    We have developed a new algorithm for the retrieval of aerosol and gases from SAGE It1 solar transmission measurements. This algorithm improves upon the NASA operational algorithm in several key aspects, including solving the problem non-linearly and incorporating a new methodology for separating the contribution of aerosols and gases. In order to extract aerosol information we have built a huge database of aerosol models for both stratospheric and tropospheric aerosols, and polar stratospheric cloud particles. This set of models allows us to calculate a vast range of possible extinction spectra for aerosols. and from these, derive a set of eigenvectors which then provide the basis set used in our inversion algorithm. Our aerosol algorithm and retrievals are described in several articles (listed in References Section) published under this grant. In particular they allow us to analyze the spectral properties of aerosols and PSCs and ultimately derive their microphysical properties. We have found some considerable differences between our spectra and the ones derived from the SAGE III operational algorithm. These are interesting as they provide an independent check on the validity of published aerosol data and, in particular, on their associated uncertainties. In order to understand these differences, we are assembling independent aerosol data from other sources with which to make comparisons. We have carried out extensive comparisons of our ozone retrievals with both SAGE III and independent lidar, ozonesonde, and satellite measurements (Polyakov et al., 2004). These show very good agreement throughout the stratosphere and help to quantify differences which can be attributed to natural variation in ozone versus that produced by algorithmic differences. In the mid - upper stratosphere, agreement with independent data was generally within 5 - 20%. but in the lower stratosphere the differences were considerably larger. We believe that a large proportion of this

  16. Science information systems: Archive, access, and retrieval

    NASA Technical Reports Server (NTRS)

    Campbell, William J.

    1991-01-01

    The objective of this research is to develop technology for the automated characterization and interactive retrieval and visualization of very large, complex scientific data sets. Technologies will be developed for the following specific areas: (1) rapidly archiving data sets; (2) automatically characterizing and labeling data in near real-time; (3) providing users with the ability to browse contents of databases efficiently and effectively; (4) providing users with the ability to access and retrieve system independent data sets electronically; and (5) automatically alerting scientists to anomalies detected in data.

  17. Automatic identification of ROI in figure images toward improving hybrid (text and image) biomedical document retrieval

    NASA Astrophysics Data System (ADS)

    You, Daekeun; Antani, Sameer; Demner-Fushman, Dina; Rahman, Md Mahmudur; Govindaraju, Venu; Thoma, George R.

    2011-01-01

    Biomedical images are often referenced for clinical decision support (CDS), educational purposes, and research. They appear in specialized databases or in biomedical publications and are not meaningfully retrievable using primarily textbased retrieval systems. The task of automatically finding the images in an article that are most useful for the purpose of determining relevance to a clinical situation is quite challenging. An approach is to automatically annotate images extracted from scientific publications with respect to their usefulness for CDS. As an important step toward achieving the goal, we proposed figure image analysis for localizing pointers (arrows, symbols) to extract regions of interest (ROI) that can then be used to obtain meaningful local image content. Content-based image retrieval (CBIR) techniques can then associate local image ROIs with identified biomedical concepts in figure captions for improved hybrid (text and image) retrieval of biomedical articles. In this work we present methods that make robust our previous Markov random field (MRF)-based approach for pointer recognition and ROI extraction. These include use of Active Shape Models (ASM) to overcome problems in recognizing distorted pointer shapes and a region segmentation method for ROI extraction. We measure the performance of our methods on two criteria: (i) effectiveness in recognizing pointers in images, and (ii) improved document retrieval through use of extracted ROIs. Evaluation on three test sets shows 87% accuracy in the first criterion. Further, the quality of document retrieval using local visual features and text is shown to be better than using visual features alone.

  18. Performance of soil moisture retrieval algorithms using multiangular L band brightness temperatures

    NASA Astrophysics Data System (ADS)

    Piles, M.; Camps, A.; Vall-Llossera, M.; Monerris, A.; Talone, M.; Sabater, J. M.

    2010-06-01

    The Soil Moisture and Ocean Salinity (SMOS) mission of the European Space Agency was successfully launched in November 2009 to provide global surface soil moisture and sea surface salinity maps. The SMOS single payload is the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS), an L band two-dimensional aperture synthesis interferometric radiometer with multiangular and polarimetric imaging capabilities. SMOS-derived soil moisture products are expected to have an accuracy of 0.04 m3/m3 over 50 × 50 km2 and a revisit time of 3 days. Previous studies have remarked the necessity of combining SMOS brightness temperatures with auxiliary data to achieve the required accuracy. However, the required auxiliary data and optimal soil moisture retrieval setup need yet to be optimized. Also, the satellite operation mode (dual polarization or full polarimetric) is an open issue to be addressed during the commissioning phase activities. In this paper, an in-depth study of the different retrieval configurations and ancillary data needed for the retrieval of soil moisture from future SMOS observations is presented. A dedicated L2 Processor Simulator software has been developed to obtain soil moisture estimates from SMOS-like brightness temperatures generated using the SMOS End-to-End Performance Simulator (SEPS). Full-polarimetric brightness temperatures are generated in SEPS, and soil moisture retrievals are performed using vertical (Tvv) and horizontal (Thh) brightness temperatures and using the first Stokes parameter (TI). Results show the accuracy obtained with the different retrieval setups for four main surface conditions combining wet and dry soils with bare and vegetation-covered surfaces. Soil moisture retrievals using TI exhibit a significantly better performance than using Thh and Tvv in all scenarios, which indicates that the dual-polarization mode should not be disregarded. The uncertainty of the ancillary data used in the minimization process and its effect on

  19. Forgetting as a consequence of retrieval: a meta-analytic review of retrieval-induced forgetting.

    PubMed

    Murayama, Kou; Miyatsu, Toshiya; Buchli, Dorothy; Storm, Benjamin C

    2014-09-01

    Retrieving a subset of items can cause the forgetting of other items, a phenomenon referred to as retrieval-induced forgetting. According to some theorists, retrieval-induced forgetting is the consequence of an inhibitory mechanism that acts to reduce the accessibility of nontarget items that interfere with the retrieval of target items. Other theorists argue that inhibition is unnecessary to account for retrieval-induced forgetting, contending instead that the phenomenon can be best explained by noninhibitory mechanisms, such as strength-based competition or blocking. The current article provides the first major meta-analysis of retrieval-induced forgetting, conducted with the primary purpose of quantitatively evaluating the multitude of findings that have been used to contrast these 2 theoretical viewpoints. The results largely supported inhibition accounts but also provided some challenging evidence, with the nature of the results often varying as a function of how retrieval-induced forgetting was assessed. Implications for further research and theory development are discussed. PMID:25180807

  20. Recollection-Based Retrieval Is Influenced by Contextual Variation at Encoding but Not at Retrieval

    PubMed Central

    Rosenstreich, Eyal; Goshen-Gottstein, Yonatan

    2015-01-01

    In this article, we investigated the effects of variations at encoding and retrieval on recollection. We argue that recollection is more likely to be affected by the processing that information undergoes at encoding than at retrieval. To date, manipulations shown to affect recollection were typically carried out at encoding. Therefore, an open question is whether these same manipulations would also affect recollection when carried out at retrieval, or whether there is an inherent connection between their effects on recollection and the encoding stage. We therefore manipulated, at either encoding or retrieval, fluency of processing (Experiment 1)—typically found not to affect recollection—and the amount of attentional resources available for processing (Experiments 2 and 3)—typically reported to affect recollection. We found that regardless of the type of manipulation, recollection was affected more by manipulations carried out at encoding and was essentially unaffected when these manipulations were carried out at retrieval. These findings suggest an inherent dependency between recollection-based retrieval and the encoding stage. It seems that because recollection is a contextual-based retrieval process, it is determined by the processing information undergoes at encoding—at the time when context is bound with the items—but not at retrieval—when context is only recovered. PMID:26135583

  1. A comparison of Boolean-based retrieval to the WAIS system for retrieval of aeronautical information

    NASA Technical Reports Server (NTRS)

    Marchionini, Gary; Barlow, Diane

    1994-01-01

    An evaluation of an information retrieval system using a Boolean-based retrieval engine and inverted file architecture and WAIS, which uses a vector-based engine, was conducted. Four research questions in aeronautical engineering were used to retrieve sets of citations from the NASA Aerospace Database which was mounted on a WAIS server and available through Dialog File 108 which served as the Boolean-based system (BBS). High recall and high precision searches were done in the BBS and terse and verbose queries were used in the WAIS condition. Precision values for the WAIS searches were consistently above the precision values for high recall BBS searches and consistently below the precision values for high precision BBS searches. Terse WAIS queries gave somewhat better precision performance than verbose WAIS queries. In every case, a small number of relevant documents retrieved by one system were not retrieved by the other, indicating the incomplete nature of the results from either retrieval system. Relevant documents in the WAIS searches were found to be randomly distributed in the retrieved sets rather than distributed by ranks. Advantages and limitations of both types of systems are discussed.

  2. Long-term health effects of neutering dogs: comparison of Labrador Retrievers with Golden Retrievers.

    PubMed

    Hart, Benjamin L; Hart, Lynette A; Thigpen, Abigail P; Willits, Neil H

    2014-01-01

    Our recent study on the effects of neutering (including spaying) in Golden Retrievers in markedly increasing the incidence of two joint disorders and three cancers prompted this study and a comparison of Golden and Labrador Retrievers. Veterinary hospital records were examined over a 13-year period for the effects of neutering during specified age ranges: before 6 mo., and during 6-11 mo., year 1 or years 2 through 8. The joint disorders examined were hip dysplasia, cranial cruciate ligament tear and elbow dysplasia. The cancers examined were lymphosarcoma, hemangiosarcoma, mast cell tumor, and mammary cancer. The results for the Golden Retriever were similar to the previous study, but there were notable differences between breeds. In Labrador Retrievers, where about 5 percent of gonadally intact males and females had one or more joint disorders, neutering at <6 mo. doubled the incidence of one or more joint disorders in both sexes. In male and female Golden Retrievers, with the same 5 percent rate of joint disorders in intact dogs, neutering at <6 mo. increased the incidence of a joint disorder to 4-5 times that of intact dogs. The incidence of one or more cancers in female Labrador Retrievers increased slightly above the 3 percent level of intact females with neutering. In contrast, in female Golden Retrievers, with the same 3 percent rate of one or more cancers in intact females, neutering at all periods through 8 years of age increased the rate of at least one of the cancers by 3-4 times. In male Golden and Labrador Retrievers neutering had relatively minor effects in increasing the occurrence of cancers. Comparisons of cancers in the two breeds suggest that the occurrence of cancers in female Golden Retrievers is a reflection of particular vulnerability to gonadal hormone removal. PMID:25020045

  3. Long-Term Health Effects of Neutering Dogs: Comparison of Labrador Retrievers with Golden Retrievers

    PubMed Central

    Hart, Benjamin L.; Hart, Lynette A.; Thigpen, Abigail P.; Willits, Neil H.

    2014-01-01

    Our recent study on the effects of neutering (including spaying) in Golden Retrievers in markedly increasing the incidence of two joint disorders and three cancers prompted this study and a comparison of Golden and Labrador Retrievers. Veterinary hospital records were examined over a 13-year period for the effects of neutering during specified age ranges: before 6 mo., and during 6–11 mo., year 1 or years 2 through 8. The joint disorders examined were hip dysplasia, cranial cruciate ligament tear and elbow dysplasia. The cancers examined were lymphosarcoma, hemangiosarcoma, mast cell tumor, and mammary cancer. The results for the Golden Retriever were similar to the previous study, but there were notable differences between breeds. In Labrador Retrievers, where about 5 percent of gonadally intact males and females had one or more joint disorders, neutering at <6 mo. doubled the incidence of one or more joint disorders in both sexes. In male and female Golden Retrievers, with the same 5 percent rate of joint disorders in intact dogs, neutering at <6 mo. increased the incidence of a joint disorder to 4–5 times that of intact dogs. The incidence of one or more cancers in female Labrador Retrievers increased slightly above the 3 percent level of intact females with neutering. In contrast, in female Golden Retrievers, with the same 3 percent rate of one or more cancers in intact females, neutering at all periods through 8 years of age increased the rate of at least one of the cancers by 3–4 times. In male Golden and Labrador Retrievers neutering had relatively minor effects in increasing the occurrence of cancers. Comparisons of cancers in the two breeds suggest that the occurrence of cancers in female Golden Retrievers is a reflection of particular vulnerability to gonadal hormone removal. PMID:25020045

  4. FRESCO+: an improved O2 A-band cloud retrieval algorithm for tropospheric trace gas retrievals

    NASA Astrophysics Data System (ADS)

    Wang, P.; Stammes, P.; van der A, R.; Pinardi, G.; van Roozendael, M.

    2008-11-01

    The FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A-band) algorithm has been used to retrieve cloud information from measurements of the O2 A-band around 760 nm by GOME, SCIAMACHY and GOME-2. The cloud parameters retrieved by FRESCO are the effective cloud fraction and cloud pressure, which are used for cloud correction in the retrieval of trace gases like O3 and NO2. To improve the cloud pressure retrieval for partly cloudy scenes, single Rayleigh scattering has been included in an improved version of the algorithm, called FRESCO+. We compared FRESCO+ and FRESCO effective cloud fractions and cloud pressures using simulated spectra and one month of GOME measured spectra. As expected, FRESCO+ gives more reliable cloud pressures over partly cloudy pixels. Simulations and comparisons with ground-based radar/lidar measurements of clouds show that the FRESCO+ cloud pressure is about the optical midlevel of the cloud. Globally averaged, the FRESCO+ cloud pressure is about 50 hPa higher than the FRESCO cloud pressure, while the FRESCO+ effective cloud fraction is about 0.01 larger. The effect of FRESCO+ cloud parameters on O3 and NO2 vertical column density (VCD) retrievals is studied using SCIAMACHY data and ground-based DOAS measurements. We find that the FRESCO+ algorithm has a significant effect on tropospheric NO2 retrievals but a minor effect on total O3 retrievals. The retrieved SCIAMACHY tropospheric NO2 VCDs using FRESCO+ cloud parameters (v1.1) are lower than the tropospheric NO2VCDs which used FRESCO cloud parameters (v1.04), in particular over heavily polluted areas with low clouds. The difference between SCIAMACHY tropospheric NO2 VCDs v1.1 and ground-based MAXDOAS measurements performed in Cabauw, The Netherlands, during the DANDELIONS campaign is about -2.12×1014molec cm-2.

  5. Microwave soil moisture retrieval under trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During 2007 a field experiment was conducted with a goal of optimizing microwave soil moisture retrieval algorithms for small to medium deciduous trees. After initial field checkout in Fall 2006, the ComRAD microwave truck instrument system was deployed to a test site with several stands of deciduo...

  6. Retrieval-Induced Forgetting: A Developmental Study

    ERIC Educational Resources Information Center

    Ford, Ruth M.; Keating, Sam; Patel, Rina

    2004-01-01

    Two studies examined the possibility of retrieval-induced forgetting by 7-year-olds. Children heard a story while viewing pictures of events mentioned in the story, each highlighting objects drawn from two distinct semantic categories (e.g. animals and food). Over the next several days, children were asked the same yes/no questions about half the…

  7. Teaching Information Retrieval Using Telediscussion Techniques.

    ERIC Educational Resources Information Center

    Heiliger, Edward M.

    This paper concerns an experiment in teaching a graduate seminar on Information Retrieval using telediscussion techniques. Outstanding persons from Project INTREX, MEDLARS, Chemical Abstracts, the University of Georgia, the SUNY biomedical Network, AEC, NASA, and DDC gave hour-long telelectures. A Conference Telephone Set was used with success.…

  8. Medical Image Retrieval: A Multimodal Approach

    PubMed Central

    Cao, Yu; Steffey, Shawn; He, Jianbiao; Xiao, Degui; Tao, Cui; Chen, Ping; Müller, Henning

    2014-01-01

    Medical imaging is becoming a vital component of war on cancer. Tremendous amounts of medical image data are captured and recorded in a digital format during cancer care and cancer research. Facing such an unprecedented volume of image data with heterogeneous image modalities, it is necessary to develop effective and efficient content-based medical image retrieval systems for cancer clinical practice and research. While substantial progress has been made in different areas of content-based image retrieval (CBIR) research, direct applications of existing CBIR techniques to the medical images produced unsatisfactory results, because of the unique characteristics of medical images. In this paper, we develop a new multimodal medical image retrieval approach based on the recent advances in the statistical graphic model and deep learning. Specifically, we first investigate a new extended probabilistic Latent Semantic Analysis model to integrate the visual and textual information from medical images to bridge the semantic gap. We then develop a new deep Boltzmann machine-based multimodal learning model to learn the joint density model from multimodal information in order to derive the missing modality. Experimental results with large volume of real-world medical images have shown that our new approach is a promising solution for the next-generation medical imaging indexing and retrieval system. PMID:26309389

  9. Interaction in Information Searching and Retrieval.

    ERIC Educational Resources Information Center

    Beaulieu, Micheline

    2000-01-01

    Explores the concepts of interaction and interactivity presented in different theoretical models in the fields of human-computer interaction (HCI) and information-seeking/searching behavior, and relates these to information retrieval (IR) research. Suggests that interaction in HCI is primarily concerned with establishing a user/system dialogue at…

  10. A Context Vector Model for Information Retrieval.

    ERIC Educational Resources Information Center

    Billhardt, Holger; Borrajo, Daniel; Maojo, Victor

    2002-01-01

    Presents an indexing and information retrieval method that, based on the vector space model, incorporates term dependencies and thus obtains semantically richer representations of documents. Highlights include term context vectors; techniques for estimating the dependencies among terms; term weights; experimental results on four text collections;…

  11. Loss of Retrieval Information in Prose Recall.

    ERIC Educational Resources Information Center

    Sehulster, Jerome R.; And Others

    The purpose of this research was to experimentally manipulate input and output orders of information and separate storage and retrieval components of prose free recall. The cued partial recall method, used in word list recall, was adapted to a prose learning task. Four short biographical stories of about 55 words each were systematically combined…

  12. Test plan for the retrieval demonstration

    SciTech Connect

    Valentich, D.J.

    1993-05-01

    This test plan describes a simulated buried waste retrieval demonstration that will be performed at the Caterpillar, Inc., Edwards Training Center located near Peoria, Illinois. The purpose of the demonstration is to determine the effectiveness of using readily available excavation equipment to retrieve, size, and handle various simulated waste forms that are similar in size, structure, and composition to those expected to be found in US Department of Energy contaminated waste pits and trenches. The objectives of this demonstration are to: meet and maintain daily production goals of 80 yd{sup 3}/day; minimize spillage and dust generation through careful and deliberate operations; document and evaluate methods for manipulating, sizing, and/or working around large objects; and document and evaluate requirements for operator augmentation and remote operation for hot test pit excavation operations. Four conditions comprising the range of environments to be evaluated include excavation of random material from below grade; stacked boxes and barrels from below grade; random materials from at grade; and stacked boxes and barrels from at grade. Results of the retrieval demonstration will reduce unknowns in the body of knowledge about retrieval equipment and procedural options for removal of buried transuranic (TRU) waste at the Idaho National Engineering Laboratory. It is anticipated that DOE will factor this information into a remedial investigation/feasibility plan leading to a final record of decision for disposition of buried TRU waste.

  13. CALIPSO lidar ratio retrieval over the ocean.

    PubMed

    Josset, Damien; Rogers, Raymond; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali; Zhai, Peng-Wang

    2011-09-12

    We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type. PMID:21935239

  14. CALIPSO Lidar Ratio Retrieval Over the Ocean

    NASA Technical Reports Server (NTRS)

    Josset, Damien B.; Rogers, Raymond R.; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali H.; Zhai, Peng-Wang

    2011-01-01

    We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type

  15. Document Retrieval Systems; Factors Affecting Search Time.

    ERIC Educational Resources Information Center

    Montgomery, K. Leon, Ed.

    An experiment was conducted to identify some of the important parameters affecting search time, a critical cost factor in retrieval systems. Using actual computer searches of Chemical Abstracts Condensate, a comparison was made between the effectiveness of linear and inverted filing systems. Since the results indicated that it was the type and…

  16. Introduction and Overview: Visualization, Retrieval, and Knowledge.

    ERIC Educational Resources Information Center

    Rorvig, Mark; Lunin, Lois F.

    1999-01-01

    Describes this perspectives issue that was designed to provide an historical background to visualization in information retrieval. Topics include knowledge, digital technology, the first visual interface to a collection at NASA (National Aeronautics and Space Administration), theoretical foundations, and applications. (LRW)

  17. Amphetamine increases errors during episodic memory retrieval.

    PubMed

    Ballard, Michael Edward; Gallo, David A; de Wit, Harriet

    2014-02-01

    Moderate doses of stimulant drugs are known to enhance memory encoding and consolidation, but their effects on memory retrieval have not been explored in depth. In laboratory animals, stimulants seem to improve retrieval of emotional memories, but comparable studies have not been carried out in humans. In the present study, we examined the effects of dextroamphetamine (AMP) on retrieval of emotional and unemotional stimuli in healthy young adults, using doses that enhanced memory formation when administered before encoding in our previous study. During 3 sessions, healthy volunteers (n = 31) received 2 doses of AMP (10 and 20 mg) and placebo in counterbalanced order under double-blind conditions. During each session, they first viewed emotional and unemotional pictures and words in a drug-free state, and then 2 days later their memory was tested, 1 hour after AMP or placebo administration. Dextroamphetamine did not affect the number of emotional or unemotional stimuli remembered, but both doses increased recall intrusions and false recognition. Dextroamphetamine (20 mg) also increased the number of positively rated picture descriptions and words generated during free recall. These data provide the first evidence that therapeutic range doses of stimulant drugs can increase memory retrieval errors. The ability of AMP to positively bias recollection of prior events could contribute to its potential for abuse. PMID:24135845

  18. CRISP (COMPUTER RETRIEVED INFORMATION ON SCIENTIFIC PROJECTS)

    EPA Science Inventory

    CRISP (Computer Retrieval of Information on Scientific Projects) is a biomedical database system containing information on research projects and programs supported by the Department of Health and Human Services. Most of the research falls within the broad category of extramural p...

  19. Stability of disposal rooms during waste retrieval

    SciTech Connect

    Brandshaug, T.

    1989-03-01

    This report presents the results of a numerical analysis to determine the stability of waste disposal rooms for vertical and horizontal emplacement during the period of waste retrieval. It is assumed that waste retrieval starts 50 years after the initial emplacement of the waste, and that access to and retrieval of the waste containers take place through the disposal rooms. It is further assumed that the disposal rooms are not back-filled. Convective cooling of the disposal rooms in preparation for waste retrieval is included in the analysis. Conditions and parameters used were taken from the Nevada Nuclear Waste Storage Investigation (NNWSI) Project Site Characterization Plan Conceptual Design Report (MacDougall et al., 1987). Thermal results are presented which illustrate the heat transfer response of the rock adjacent to the disposal rooms. Mechanical results are presented which illustrate the predicted distribution of stress, joint slip, and room deformations for the period of time investigated. Under the assumption that the host rock can be classified as ``fair to good`` using the Geomechanics Classification System (Bieniawski, 1974), only light ground support would appear to be necessary for the disposal rooms to remain stable. 23 refs., 28 figs., 2 tabs.

  20. 3D object retrieval using salient views.

    PubMed

    Atmosukarto, Indriyati; Shapiro, Linda G

    2013-06-01

    This paper presents a method for selecting salient 2D views to describe 3D objects for the purpose of retrieval. The views are obtained by first identifying salient points via a learning approach that uses shape characteristics of the 3D points (Atmosukarto and Shapiro in International workshop on structural, syntactic, and statistical pattern recognition, 2008; Atmosukarto and Shapiro in ACM multimedia information retrieval, 2008). The salient views are selected by choosing views with multiple salient points on the silhouette of the object. Silhouette-based similarity measures from Chen et al. (Comput Graph Forum 22(3):223-232, 2003) are then used to calculate the similarity between two 3D objects. Retrieval experiments were performed on three datasets: the Heads dataset, the SHREC2008 dataset, and the Princeton dataset. Experimental results show that the retrieval results using the salient views are comparable to the existing light field descriptor method (Chen et al. in Comput Graph Forum 22(3):223-232, 2003), and our method achieves a 15-fold speedup in the feature extraction computation time. PMID:23833704

  1. Exploring biases in exoplanet spectroscopy retrievals

    NASA Astrophysics Data System (ADS)

    Feng, Ying; Fortney, Jonathan; Line, Michael R.; Morley, Caroline

    2015-12-01

    Spectra from the atmospheres of transiting planets and imaged planets are now being routinely achieved. The interpretation of these spectra gives us a window into the physics and chemistry of these atmospheres, as well as a better understanding of planet formation. Over the past several years retrievals of exoplanet spectra have been used to obtain chemical abundances and thermal structures, along with assessments of uncertainties on these quantities. However, any potential biases inherent in these methods have yet to be fully explored. The atmospheres we observe are inherently three-dimensional (3D) structures that feature gradients in temperatures and chemical abundances, as well as hot spots, cold spots, storms, and cloud patchiness. How well does the assumption of retrieving 1D hemispheric average conditions represent the true state of a 3D atmosphere? Can we be led astray? Answering these questions are important today, and will only become more important as data quality improves. Using a descendent of the CHIMERA retrieval code, here I present the results of how retrievals perform on more complex scenarios. We start with the emitted spectrum from the average of two pressure-temperature profiles, one warmer, one colder, and move on to more sophisticated, but still realistic, scenarios. Our work makes use of a new code we have developed to construct spectra from arbitrary 3D model atmospheres.

  2. Improving aerosol retrieval over urban areas

    NASA Astrophysics Data System (ADS)

    Picón, A. J.; Wu, Y.; Gross, B.; Moshary, F.; Ahmed, S. A.

    2010-12-01

    Aerosol retrieval over urban areas is complicated since surface models in the operational algorithms are based on vegetation models such as the case of MODIS. To improve satellite retrieval of aerosols in urban areas, we use simultaneous AERONET radiometer and MODIS measurements in combination to refine surface albedo models. Refined surface models have been implemented for NYC and Mexico City demonstrating significant improvement in AOD in terms of accuracy and spatial resolution. Based on these direct retrievals of the surface reflection for the MODIS Land Aerosol Bands, we were able to show that current parameterizations of the surface as a function of the Modified Vegetation Index are not in good agreement either quantitatively or qualitatively. Further comparisons in other urban areas (eg. Beijing) show that for cases with surface reflectance ratios sufficiently high at the AERONET site, similar over biases can be observed. On the other hand, other cities such as Kanpur, Buenos Aires and Rome do not show any significant bias which can be traced to the fact that these sites are located in regions with less urban surface correlations. Further comparisons in these urban centers are also made with other satellites aerosol retrievals such as POLDER, MISR and OMI.

  3. Prediction During Learning of Later Retrievability.

    ERIC Educational Resources Information Center

    Lovelace, Eugene A.

    Evidence was found for an ability to monitor during learning the degree of retrievability of the to-be-learned material from memory at time of a subsequent test. Students were given three successive study trials to learn either a list of 60 paired associates or a free-recall list of 60 "unrelated" words. During a fourth study trial, they rated on…

  4. Fernald Silo Remote Retrieval Tool Development

    SciTech Connect

    Varma, V.K.

    2004-05-18

    A long-reach tool was developed to remove discrete objects from the silos at the Fernald Environmental Management Project in Ohio. If they are not removed, these objects can potentially cause problems during the retrieval and transfer of waste from the silos. Most of the objects are on top of the Bentogrout cap inside the silos at or near the primary opening into the tank and will therefore require only vertical lifting. The objects are located about 20 ft from the top of the silo. Although most of the objects can be retrieved from 20 ft, the long-reach tool was designed to for a reach up to 40 ft in case objects roll towards the walls of the tank or need to be removed during heel retrieval operations. This report provides a detailed description of the tool that was developed, tested, and demonstrated at the Tanks Technology Cold Test Facility at Oak Ridge National Laboratory. Scaffolding was erected over two experimental cells to simulate the 40-ft maximum working depth anticipated in the silos at Fernald. Plastic bottles and plastic sheeting simulated the debris that could be encountered during waste retrieval operations.

  5. Retrievals with the Infrared Atmospheric Sounding Interferometer

    NASA Technical Reports Server (NTRS)

    Zhou, Daniel K.; Liu, Xu; Larar, Allen M.; Smith, William L.; Taylor, Jonathan P.; Schlussel, Peter; Strow, L. Larrabee; Calbet, Xavier; Mango, Stephen A.

    2007-01-01

    The Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp satellite was launched on October 19, 2006. The Joint Airborne IASI Validation Experiment (JAIVEx) was conducted during April 2007 mainly for validation of the IASI on the MetOp satellite. IASI possesses an ultra-spectral resolution of 0.25/cm and a spectral coverage from 645 to 2760/cm. Ultraspectral resolution infrared spectral radiance obtained from near nadir observations provide atmospheric, surface, and cloud property information. An advanced retrieval algorithm with a fast radiative transfer model, including cloud effects, is used for atmospheric profile and cloud parameter retrieval. Preliminary retrievals of atmospheric soundings, surface properties, and cloud optical/microphysical properties with the IASI observations during the JAIVEx are obtained and presented. These retrievals are further inter-compared with those obtained from airborne FTS system, such as the NPOESS Airborne Sounder Testbed Interferometer (NAST-I), dedicated dropsondes, radiosondes, and ground based Raman Lidar. The capabilities of satellite ultra-spectral sounder such as the IASI are investigated.

  6. Chinese Brush Calligraphy Character Retrieval and Learning

    ERIC Educational Resources Information Center

    Zhuang, Yueting; Zhang, Xiafen; Lu, Weiming; Wu, Fei

    2007-01-01

    Chinese brush calligraphy is a valuable civilization legacy and a high art of scholarship. It is still popular in Chinese banners, newspaper mastheads, university names, and celebration gifts. There are Web sites that try to help people enjoy and learn Chinese calligraphy. However, there lacks advanced services such as content-based retrieval or…

  7. Millennial Students' Mental Models of Information Retrieval

    ERIC Educational Resources Information Center

    Holman, Lucy

    2009-01-01

    This qualitative study examines first-year college students' online search habits in order to identify patterns in millennials' mental models of information retrieval. The study employed a combination of modified contextual inquiry and concept mapping methodologies to elicit students' mental models. The researcher confirmed previously observed…

  8. A Written Experiment on Retrieval Dialogue.

    ERIC Educational Resources Information Center

    Smith, John Miles

    An experiment is described for determining the vocabulary and grammar of user retrieval requests in natural English as a guide in the design of a language for man-machine communication through a typewriter console. This experiment tested written dialog in follow-up to an experiment that tested oral dialog. Subjects repeated behavior observed in…

  9. An Oral Experiment on Retrieval Dialogue.

    ERIC Educational Resources Information Center

    Smith, John Miles

    An experiment is described for determining the vocabulary and grammar of user retrieval requests in natural English as a guide in the design of a language for man-machine communication through a typewriter console. Results of ten question-answer dialogs are discussed. In oral communication, initial requests were most frequently declarative and…

  10. Document Retrieval Based on Clustered Files.

    ERIC Educational Resources Information Center

    Murray, Daniel McClure

    A retrieval system is considered in which document descriptions are stored and accessed in groups called clusters. All items in a cluster meet common similarity criteria and are represented by a composite entity called a profile. In large collections, profiles themselves are clustered and additional levels of profiles are generated. This entire…

  11. Artist drawings of the Teleoperator Retrieval System

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A drawing of a Teleoperator Retrieval System (TRS) which is being developed by NASA for use begining in late 1979. This spacecraft is illustrated being used to re-boost the Skylab space station to a higher orbit (23630); A labeled drawing of a TRS which is being developed by NASA (23631).

  12. Introduction: Natural Language Processing and Information Retrieval.

    ERIC Educational Resources Information Center

    Smeaton, Alan F.

    1990-01-01

    Discussion of research into information and text retrieval problems highlights the work with automatic natural language processing (NLP) that is reported in this issue. Topics discussed include the occurrences of nominal compounds; anaphoric references; discontinuous language constructs; automatic back-of-the-book indexing; and full-text analysis.…

  13. NATIONAL PESTICIDE INFORMATION RETRIEVAL SYSTEM (NPIRS)

    EPA Science Inventory

    The National Pesticide Information Retrieval System (NPIRS) is a collection of pesticide-related databases available through subscription to the Center for Environmental and Regulatory Information Systems, CERIS. The following is a summary of data found in the databases, data sou...

  14. Neural Systems behind Word and Concept Retrieval

    ERIC Educational Resources Information Center

    Damasio, H.; Tranel, D.; Grabowski, T.; Adolphs, R.; Damasio, A.

    2004-01-01

    Using both the lesion method and functional imaging (positron emission tomography) in large cohorts of subjects investigated with the same experimental tasks, we tested the following hypotheses: (A) that the retrieval of words which denote concrete entities belonging to distinct conceptual categories depends upon partially segregated regions in…

  15. Applications of Machine Learning in Information Retrieval.

    ERIC Educational Resources Information Center

    Cunningham, Sally Jo; Witten, Ian H.; Littin, James

    1999-01-01

    Introduces the basic ideas that underpin applications of machine learning to information retrieval. Describes applications of machine learning to text categorization. Considers how machine learning can be applied to the query-formulation process. Examines methods of document filtering, where the user specifies a query that is to be applied to an…

  16. Is Retrieval Mediated after Repeated Testing?

    ERIC Educational Resources Information Center

    Kole, James A.; Healy, Alice F.

    2013-01-01

    In 2 main experiments, the mediated priming effect was used to determine whether retrieval continues to be mediated after repeated testing. In each experiment, participants used the keyword method to learn French vocabulary, then completed a modified lexical decision task in which they first translated a French word, and then made a lexical…

  17. Retrieval-Induced Forgetting of Arithmetic Facts

    ERIC Educational Resources Information Center

    Campbell, Jamie I. D.; Thompson, Valerie A.

    2012-01-01

    Retrieval-induced forgetting (RIF) is a widely studied phenomenon of human memory, but RIF of arithmetic facts remains relatively unexplored. In 2 experiments, we investigated RIF of simple addition facts (2 + 3 = 5) from practice of their multiplication counterparts (2 x 3 = 6). In both experiments, robust RIF expressed in response times occurred…

  18. Understanding Student Article Retrieval Behaviors: Instructional Implications

    ERIC Educational Resources Information Center

    Cook-Cottone, Catherine P.; Dutt-Doner, Karen; Schoen, David

    2005-01-01

    This study evaluates the use of full-text databases amongst 425 undergraduate and graduate students in western New York. A review of literature implicated convenience, time issues, article retrieval option knowledge, and the appreciation and understanding of research article quality as potential predictors of full-text reliance. These variables…

  19. 3D object retrieval using salient views

    PubMed Central

    Shapiro, Linda G.

    2013-01-01

    This paper presents a method for selecting salient 2D views to describe 3D objects for the purpose of retrieval. The views are obtained by first identifying salient points via a learning approach that uses shape characteristics of the 3D points (Atmosukarto and Shapiro in International workshop on structural, syntactic, and statistical pattern recognition, 2008; Atmosukarto and Shapiro in ACM multimedia information retrieval, 2008). The salient views are selected by choosing views with multiple salient points on the silhouette of the object. Silhouette-based similarity measures from Chen et al. (Comput Graph Forum 22(3):223–232, 2003) are then used to calculate the similarity between two 3D objects. Retrieval experiments were performed on three datasets: the Heads dataset, the SHREC2008 dataset, and the Princeton dataset. Experimental results show that the retrieval results using the salient views are comparable to the existing light field descriptor method (Chen et al. in Comput Graph Forum 22(3):223–232, 2003), and our method achieves a 15-fold speedup in the feature extraction computation time. PMID:23833704

  20. BELTracker: evidence sentence retrieval for BEL statements.

    PubMed

    Rastegar-Mojarad, Majid; Komandur Elayavilli, Ravikumar; Liu, Hongfang

    2016-01-01

    Biological expression language (BEL) is one of the main formal representation models of biological networks. The primary source of information for curating biological networks in BEL representation has been literature. It remains a challenge to identify relevant articles and the corresponding evidence statements for curating and validating BEL statements. In this paper, we describe BELTracker, a tool used to retrieve and rank evidence sentences from PubMed abstracts and full-text articles for a given BEL statement (per the 2015 task requirements of BioCreative V BEL Task). The system is comprised of three main components, (i) translation of a given BEL statement to an information retrieval (IR) query, (ii) retrieval of relevant PubMed citations and (iii) finding and ranking the evidence sentences in those citations. BELTracker uses a combination of multiple approaches based on traditional IR, machine learning, and heuristics to accomplish the task. The system identified and ranked at least one fully relevant evidence sentence in the top 10 retrieved sentences for 72 out of 97 BEL statements in the test set. BELTracker achieved a precision of 0.392, 0.532 and 0.615 when evaluated with three criteria, namely full, relaxed and context criteria, respectively, by the task organizers. Our team at Mayo Clinic was the only participant in this task. BELTracker is available as a RESTful API and is available for public use.Database URL: http://www.openbionlp.org:8080/BelTracker/finder/Given_BEL_Statement. PMID:27173525