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Sample records for finding sequential patterns

  1. Research on parallel algorithm for sequential pattern mining

    Science.gov (United States)

    Zhou, Lijuan; Qin, Bai; Wang, Yu; Hao, Zhongxiao

    2008-03-01

    Sequential pattern mining is the mining of frequent sequences related to time or other orders from the sequence database. Its initial motivation is to discover the laws of customer purchasing in a time section by finding the frequent sequences. In recent years, sequential pattern mining has become an important direction of data mining, and its application field has not been confined to the business database and has extended to new data sources such as Web and advanced science fields such as DNA analysis. The data of sequential pattern mining has characteristics as follows: mass data amount and distributed storage. Most existing sequential pattern mining algorithms haven't considered the above-mentioned characteristics synthetically. According to the traits mentioned above and combining the parallel theory, this paper puts forward a new distributed parallel algorithm SPP(Sequential Pattern Parallel). The algorithm abides by the principal of pattern reduction and utilizes the divide-and-conquer strategy for parallelization. The first parallel task is to construct frequent item sets applying frequent concept and search space partition theory and the second task is to structure frequent sequences using the depth-first search method at each processor. The algorithm only needs to access the database twice and doesn't generate the candidated sequences, which abates the access time and improves the mining efficiency. Based on the random data generation procedure and different information structure designed, this paper simulated the SPP algorithm in a concrete parallel environment and implemented the AprioriAll algorithm. The experiments demonstrate that compared with AprioriAll, the SPP algorithm had excellent speedup factor and efficiency.

  2. An Efficient System Based On Closed Sequential Patterns for Web Recommendations

    OpenAIRE

    Utpala Niranjan; R.B.V. Subramanyam; V-Khana

    2010-01-01

    Sequential pattern mining, since its introduction has received considerable attention among the researchers with broad applications. The sequential pattern algorithms generally face problems when mining long sequential patterns or while using very low support threshold. One possible solution of such problems is by mining the closed sequential patterns, which is a condensed representation of sequential patterns. Recently, several researchers have utilized the sequential pattern discovery for d...

  3. Sequential lineup presentation: Patterns and policy

    OpenAIRE

    Lindsay, R C L; Mansour, Jamal K; Beaudry, J L; Leach, A-M; Bertrand, M I

    2009-01-01

    Sequential lineups were offered as an alternative to the traditional simultaneous lineup. Sequential lineups reduce incorrect lineup selections; however, the accompanying loss of correct identifications has resulted in controversy regarding adoption of the technique. We discuss the procedure and research relevant to (1) the pattern of results found using sequential versus simultaneous lineups; (2) reasons (theory) for differences in witness responses; (3) two methodological issues; and (4) im...

  4. A node linkage approach for sequential pattern mining.

    Directory of Open Access Journals (Sweden)

    Osvaldo Navarro

    Full Text Available Sequential Pattern Mining is a widely addressed problem in data mining, with applications such as analyzing Web usage, examining purchase behavior, and text mining, among others. Nevertheless, with the dramatic increase in data volume, the current approaches prove inefficient when dealing with large input datasets, a large number of different symbols and low minimum supports. In this paper, we propose a new sequential pattern mining algorithm, which follows a pattern-growth scheme to discover sequential patterns. Unlike most pattern growth algorithms, our approach does not build a data structure to represent the input dataset, but instead accesses the required sequences through pseudo-projection databases, achieving better runtime and reducing memory requirements. Our algorithm traverses the search space in a depth-first fashion and only preserves in memory a pattern node linkage and the pseudo-projections required for the branch being explored at the time. Experimental results show that our new approach, the Node Linkage Depth-First Traversal algorithm (NLDFT, has better performance and scalability in comparison with state of the art algorithms.

  5. Mining Emerging Sequential Patterns for Activity Recognition in Body Sensor Networks

    DEFF Research Database (Denmark)

    Gu, Tao; Wang, Liang; Chen, Hanhua

    2010-01-01

    Body Sensor Networks oer many applications in healthcare, well-being and entertainment. One of the emerging applications is recognizing activities of daily living. In this paper, we introduce a novel knowledge pattern named Emerging Sequential Pattern (ESP)|a sequential pattern that discovers...... signicant class dierences|to recognize both simple (i.e., sequential) and complex (i.e., interleaved and concurrent) activities. Based on ESPs, we build our complex activity models directly upon the sequential model to recognize both activity types. We conduct comprehensive empirical studies to evaluate...

  6. Zips : mining compressing sequential patterns in streams

    NARCIS (Netherlands)

    Hoang, T.L.; Calders, T.G.K.; Yang, J.; Mörchen, F.; Fradkin, D.; Chau, D.H.; Vreeken, J.; Leeuwen, van M.; Faloutsos, C.

    2013-01-01

    We propose a streaming algorithm, based on the minimal description length (MDL) principle, for extracting non-redundant sequential patterns. For static databases, the MDL-based approach that selects patterns based on their capacity to compress data rather than their frequency, was shown to be

  7. Dynamics-based sequential memory: Winnerless competition of patterns

    International Nuclear Information System (INIS)

    Seliger, Philip; Tsimring, Lev S.; Rabinovich, Mikhail I.

    2003-01-01

    We introduce a biologically motivated dynamical principle of sequential memory which is based on winnerless competition (WLC) of event images. This mechanism is implemented in a two-layer neural model of sequential spatial memory. We present the learning dynamics which leads to the formation of a WLC network. After learning, the system is capable of associative retrieval of prerecorded sequences of patterns

  8. Mining of high utility-probability sequential patterns from uncertain databases.

    Directory of Open Access Journals (Sweden)

    Binbin Zhang

    Full Text Available High-utility sequential pattern mining (HUSPM has become an important issue in the field of data mining. Several HUSPM algorithms have been designed to mine high-utility sequential patterns (HUPSPs. They have been applied in several real-life situations such as for consumer behavior analysis and event detection in sensor networks. Nonetheless, most studies on HUSPM have focused on mining HUPSPs in precise data. But in real-life, uncertainty is an important factor as data is collected using various types of sensors that are more or less accurate. Hence, data collected in a real-life database can be annotated with existing probabilities. This paper presents a novel pattern mining framework called high utility-probability sequential pattern mining (HUPSPM for mining high utility-probability sequential patterns (HUPSPs in uncertain sequence databases. A baseline algorithm with three optional pruning strategies is presented to mine HUPSPs. Moroever, to speed up the mining process, a projection mechanism is designed to create a database projection for each processed sequence, which is smaller than the original database. Thus, the number of unpromising candidates can be greatly reduced, as well as the execution time for mining HUPSPs. Substantial experiments both on real-life and synthetic datasets show that the designed algorithm performs well in terms of runtime, number of candidates, memory usage, and scalability for different minimum utility and minimum probability thresholds.

  9. Involvement of Working Memory in College Students' Sequential Pattern Learning and Performance

    Science.gov (United States)

    Kundey, Shannon M. A.; De Los Reyes, Andres; Rowan, James D.; Lee, Bern; Delise, Justin; Molina, Sabrina; Cogdill, Lindsay

    2013-01-01

    When learning highly organized sequential patterns of information, humans and nonhuman animals learn rules regarding the hierarchical structures of these sequences. In three experiments, we explored the role of working memory in college students' sequential pattern learning and performance in a computerized task involving a sequential…

  10. Modeling eye gaze patterns in clinician-patient interaction with lag sequential analysis.

    Science.gov (United States)

    Montague, Enid; Xu, Jie; Chen, Ping-Yu; Asan, Onur; Barrett, Bruce P; Chewning, Betty

    2011-10-01

    The aim of this study was to examine whether lag sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multiuser health care settings in which trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Nonverbal communication patterns are important aspects of clinician-patient interactions and may affect patient outcomes. The eye gaze behaviors of clinicians and patients in 110 videotaped medical encounters were analyzed using the lag sequential method to identify significant behavior sequences. Lag sequential analysis included both event-based lag and time-based lag. Results from event-based lag analysis showed that the patient's gaze followed that of the clinician, whereas the clinician's gaze did not follow the patient's. Time-based sequential analysis showed that responses from the patient usually occurred within 2 s after the initial behavior of the clinician. Our data suggest that the clinician's gaze significantly affects the medical encounter but that the converse is not true. Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs.

  11. From sequential to parallel programming with patterns

    CERN Document Server

    CERN. Geneva

    2018-01-01

    To increase in both performance and efficiency, our programming models need to adapt to better exploit modern processors. The classic idioms and patterns for programming such as loops, branches or recursion are the pillars of almost every code and are well known among all programmers. These patterns all have in common that they are sequential in nature. Embracing parallel programming patterns, which allow us to program for multi- and many-core hardware in a natural way, greatly simplifies the task of designing a program that scales and performs on modern hardware, independently of the used programming language, and in a generic way.

  12. Cystic periventricular leukomalacia in the neonate: analysis of sequential sonographic findings and neurologic outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Seok; Yoo, Dong Soo [Dankook University College of Medicine, Cheonan (Korea, Republic of)

    2003-07-01

    To analyse the sequential sonographic findings of cystic PVL and to evaluate relationship between sonographic grading of PVL and patterns of neurologic outcomes. Authors have retrospectively analysed the sequential sonographic findings of 36 cases of PVL in the preterm neonates. Initial sonographic features done within 3 days of life were divided into 3 patients such as normal, localized, and diffuse hyperechogenic flare. Grading of PVL confirmed by follow-up studies was classified as involvement of one lobe (grade 1), two lobes (grade 2) and more than extent of grade 2 (grade 3). The relationship between sonographic grading of leukomalacia and later neurologic outcomes were also analysed. Initial sonographic patterns according to grading of PVL were normal pattern in seven of nine (77.8%) of grade 1, diffuse hyperechogenic flares in five of eight cases of grade 2 and in 13 of 16 cases of grade 3. There was a significant difference between the grades and frequency of pattern of diffuse hyperechoic flare (p=0.021). Average detection timing of cystic PVL was 38.4{+-}18.9 days in grade 1, 29.8{+-}14 days in grade 2, and 19.1{+-}5.6 days in grade 3 with a significant statistical difference between the detection time and grades (p=0.037). Cerebral palsy has occurred in 62.5% of grade 1 and 100% of grade 2 and grade 3 (p=0.043). Frequency of spastic quadriplegia was higher in grade 3 (76.5%) than in grade 1 (25%) and grade 2 (12.5%) (p=0.001). Most of grade 1 cystic PVL revealed normal pattern of white matter echogenicity in initial ultrasonography and needed follow up examination over one month period. Spastic quadriplegia occured mainly in patients with grade 3 cystic PVL.

  13. Cystic periventricular leukomalacia in the neonate: analysis of sequential sonographic findings and neurologic outcomes

    International Nuclear Information System (INIS)

    Lee, Young Seok; Yoo, Dong Soo

    2003-01-01

    To analyse the sequential sonographic findings of cystic PVL and to evaluate relationship between sonographic grading of PVL and patterns of neurologic outcomes. Authors have retrospectively analysed the sequential sonographic findings of 36 cases of PVL in the preterm neonates. Initial sonographic features done within 3 days of life were divided into 3 patients such as normal, localized, and diffuse hyperechogenic flare. Grading of PVL confirmed by follow-up studies was classified as involvement of one lobe (grade 1), two lobes (grade 2) and more than extent of grade 2 (grade 3). The relationship between sonographic grading of leukomalacia and later neurologic outcomes were also analysed. Initial sonographic patterns according to grading of PVL were normal pattern in seven of nine (77.8%) of grade 1, diffuse hyperechogenic flares in five of eight cases of grade 2 and in 13 of 16 cases of grade 3. There was a significant difference between the grades and frequency of pattern of diffuse hyperechoic flare (p=0.021). Average detection timing of cystic PVL was 38.4±18.9 days in grade 1, 29.8±14 days in grade 2, and 19.1±5.6 days in grade 3 with a significant statistical difference between the detection time and grades (p=0.037). Cerebral palsy has occurred in 62.5% of grade 1 and 100% of grade 2 and grade 3 (p=0.043). Frequency of spastic quadriplegia was higher in grade 3 (76.5%) than in grade 1 (25%) and grade 2 (12.5%) (p=0.001). Most of grade 1 cystic PVL revealed normal pattern of white matter echogenicity in initial ultrasonography and needed follow up examination over one month period. Spastic quadriplegia occured mainly in patients with grade 3 cystic PVL

  14. Hypotension Risk Prediction via Sequential Contrast Patterns of ICU Blood Pressure.

    Science.gov (United States)

    Ghosh, Shameek; Feng, Mengling; Nguyen, Hung; Li, Jinyan

    2016-09-01

    Acute hypotension is a significant risk factor for in-hospital mortality at intensive care units. Prolonged hypotension can cause tissue hypoperfusion, leading to cellular dysfunction and severe injuries to multiple organs. Prompt medical interventions are thus extremely important for dealing with acute hypotensive episodes (AHE). Population level prognostic scoring systems for risk stratification of patients are suboptimal in such scenarios. However, the design of an efficient risk prediction system can significantly help in the identification of critical care patients, who are at risk of developing an AHE within a future time span. Toward this objective, a pattern mining algorithm is employed to extract informative sequential contrast patterns from hemodynamic data, for the prediction of hypotensive episodes. The hypotensive and normotensive patient groups are extracted from the MIMIC-II critical care research database, following an appropriate clinical inclusion criteria. The proposed method consists of a data preprocessing step to convert the blood pressure time series into symbolic sequences, using a symbolic aggregate approximation algorithm. Then, distinguishing subsequences are identified using the sequential contrast mining algorithm. These subsequences are used to predict the occurrence of an AHE in a future time window separated by a user-defined gap interval. Results indicate that the method performs well in terms of the prediction performance as well as in the generation of sequential patterns of clinical significance. Hence, the novelty of sequential patterns is in their usefulness as potential physiological biomarkers for building optimal patient risk stratification systems and for further clinical investigation of interesting patterns in critical care patients.

  15. Sequential infiltration synthesis for enhancing multiple-patterning lithography

    Science.gov (United States)

    Darling, Seth B.; Elam, Jeffrey W.; Tseng, Yu-Chih

    2017-06-20

    Simplified methods of multiple-patterning photolithography using sequential infiltration synthesis to modify the photoresist such that it withstands plasma etching better than unmodified resist and replaces one or more hard masks and/or a freezing step in MPL processes including litho-etch-litho-etch photolithography or litho-freeze-litho-etch photolithography.

  16. Sequential pattern recognition by maximum conditional informativity

    Czech Academy of Sciences Publication Activity Database

    Grim, Jiří

    2014-01-01

    Roč. 45, č. 1 (2014), s. 39-45 ISSN 0167-8655 R&D Projects: GA ČR(CZ) GA14-02652S; GA ČR(CZ) GA14-10911S Keywords : Multivariate statistics * Statistical pattern recognition * Sequential decision making * Product mixtures * EM algorithm * Shannon information Subject RIV: IN - Informatics, Computer Sci ence Impact factor: 1.551, year: 2014 http://library.utia.cas.cz/separaty/2014/RO/grim-0428565.pdf

  17. Robust real-time pattern matching using bayesian sequential hypothesis testing.

    Science.gov (United States)

    Pele, Ofir; Werman, Michael

    2008-08-01

    This paper describes a method for robust real time pattern matching. We first introduce a family of image distance measures, the "Image Hamming Distance Family". Members of this family are robust to occlusion, small geometrical transforms, light changes and non-rigid deformations. We then present a novel Bayesian framework for sequential hypothesis testing on finite populations. Based on this framework, we design an optimal rejection/acceptance sampling algorithm. This algorithm quickly determines whether two images are similar with respect to a member of the Image Hamming Distance Family. We also present a fast framework that designs a near-optimal sampling algorithm. Extensive experimental results show that the sequential sampling algorithm performance is excellent. Implemented on a Pentium 4 3 GHz processor, detection of a pattern with 2197 pixels, in 640 x 480 pixel frames, where in each frame the pattern rotated and was highly occluded, proceeds at only 0.022 seconds per frame.

  18. Energy-separated sequential irradiation for ripple pattern tailoring on silicon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Tanuj [Department of Physics, Central University of Haryana, Jant-Pali, Mahendergarh 1123029 (India); Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Kumar, Manish, E-mail: manishbharadwaj@gmail.com [Department of Physics, Central University of Rajasthan, Kishangarh 305801 (India); Panchal, Vandana [Department of Physics, National Institute of Technology, Kurukshetra 136119 (India); Sahoo, P.K. [School of Physical Sciences, National Institute of Science Education and Research, Bhubaneswar 751005 (India); Kanjilal, D. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2015-12-01

    Highlights: • A new process for controlling the near-surface amorphization of ripples on Si surfaces. • Ripples generation by 100 KeV Ar{sup +} and amorphization control by 60 KeV Ar{sup +} irradiation. • Advantage of energy-separated irradiation demonstrated by detailed RBS and AFM studies. • Relevant mechanism is presented on the basis of DAMAGE and SIMNRA simulations. • Key role of solid flow towards the amorphous/crystalline interface is demonstrated. - Abstract: Nanoscale ripples on semiconductor surfaces have potential application in biosensing and optoelectronics, but suffer from uncontrolled surface-amorphization when prepared by conventional ion-irradiation methods. A two-step, energy-separated sequential-irradiation enables simultaneous control of surface-amorphization and ripple-dimensions on Si(1 0 0). The evolution of ripples using 100 keV Ar{sup +} bombardment and further tuning of the patterns using a sequential-irradiation by 60 keV Ar{sup +} at different fluences are demonstrated. The advantage of this approach as opposed to increased fluence at the same energy is clarified by atomic force microscopy and Rutherford backscattering spectroscopy investigations. The explanation of our findings is presented through DAMAGE simulation.

  19. Sequentially firing neurons confer flexible timing in neural pattern generators

    International Nuclear Information System (INIS)

    Urban, Alexander; Ermentrout, Bard

    2011-01-01

    Neuronal networks exhibit a variety of complex spatiotemporal patterns that include sequential activity, synchrony, and wavelike dynamics. Inhibition is the primary means through which such patterns are implemented. This behavior is dependent on both the intrinsic dynamics of the individual neurons as well as the connectivity patterns. Many neural circuits consist of networks of smaller subcircuits (motifs) that are coupled together to form the larger system. In this paper, we consider a particularly simple motif, comprising purely inhibitory interactions, which generates sequential periodic dynamics. We first describe the dynamics of the single motif both for general balanced coupling (all cells receive the same number and strength of inputs) and then for a specific class of balanced networks: circulant systems. We couple these motifs together to form larger networks. We use the theory of weak coupling to derive phase models which, themselves, have a certain structure and symmetry. We show that this structure endows the coupled system with the ability to produce arbitrary timing relationships between symmetrically coupled motifs and that the phase relationships are robust over a wide range of frequencies. The theory is applicable to many other systems in biology and physics.

  20. Efficient sequential and parallel algorithms for finding edit distance based motifs.

    Science.gov (United States)

    Pal, Soumitra; Xiao, Peng; Rajasekaran, Sanguthevar

    2016-08-18

    Motif search is an important step in extracting meaningful patterns from biological data. The general problem of motif search is intractable and there is a pressing need to develop efficient, exact and approximation algorithms to solve this problem. In this paper, we present several novel, exact, sequential and parallel algorithms for solving the (l,d) Edit-distance-based Motif Search (EMS) problem: given two integers l,d and n biological strings, find all strings of length l that appear in each input string with atmost d errors of types substitution, insertion and deletion. One popular technique to solve the problem is to explore for each input string the set of all possible l-mers that belong to the d-neighborhood of any substring of the input string and output those which are common for all input strings. We introduce a novel and provably efficient neighborhood exploration technique. We show that it is enough to consider the candidates in neighborhood which are at a distance exactly d. We compactly represent these candidate motifs using wildcard characters and efficiently explore them with very few repetitions. Our sequential algorithm uses a trie based data structure to efficiently store and sort the candidate motifs. Our parallel algorithm in a multi-core shared memory setting uses arrays for storing and a novel modification of radix-sort for sorting the candidate motifs. The algorithms for EMS are customarily evaluated on several challenging instances such as (8,1), (12,2), (16,3), (20,4), and so on. The best previously known algorithm, EMS1, is sequential and in estimated 3 days solves up to instance (16,3). Our sequential algorithms are more than 20 times faster on (16,3). On other hard instances such as (9,2), (11,3), (13,4), our algorithms are much faster. Our parallel algorithm has more than 600 % scaling performance while using 16 threads. Our algorithms have pushed up the state-of-the-art of EMS solvers and we believe that the techniques introduced in

  1. Sequential super-stereotypy of an instinctive fixed action pattern in hyper-dopaminergic mutant mice: a model of obsessive compulsive disorder and Tourette's

    Directory of Open Access Journals (Sweden)

    Houchard Kimberly R

    2005-02-01

    Full Text Available Abstract Background Excessive sequential stereotypy of behavioral patterns (sequential super-stereotypy in Tourette's syndrome and obsessive compulsive disorder (OCD is thought to involve dysfunction in nigrostriatal dopamine systems. In sequential super-stereotypy, patients become trapped in overly rigid sequential patterns of action, language, or thought. Some instinctive behavioral patterns of animals, such as the syntactic grooming chain pattern of rodents, have sufficiently complex and stereotyped serial structure to detect potential production of overly-rigid sequential patterns. A syntactic grooming chain is a fixed action pattern that serially links up to 25 grooming movements into 4 predictable phases that follow 1 syntactic rule. New mutant mouse models allow gene-based manipulation of brain function relevant to sequential patterns, but no current animal model of spontaneous OCD-like behaviors has so far been reported to exhibit sequential super-stereotypy in the sense of a whole complex serial pattern that becomes stronger and excessively rigid. Here we used a hyper-dopaminergic mutant mouse to examine whether an OCD-like behavioral sequence in animals shows sequential super-stereotypy. Knockdown mutation of the dopamine transporter gene (DAT causes extracellular dopamine levels in the neostriatum of these adult mutant mice to rise to 170% of wild-type control levels. Results We found that the serial pattern of this instinctive behavioral sequence becomes strengthened as an entire entity in hyper-dopaminergic mutants, and more resistant to interruption. Hyper-dopaminergic mutant mice have stronger and more rigid syntactic grooming chain patterns than wild-type control mice. Mutants showed sequential super-stereotypy in the sense of having more stereotyped and predictable syntactic grooming sequences, and were also more likely to resist disruption of the pattern en route, by returning after a disruption to complete the pattern from the

  2. Random sequential adsorption: from continuum to lattice and pre-patterned substrates

    International Nuclear Information System (INIS)

    Cadilhe, A; Araujo, N A M; Privman, Vladimir

    2007-01-01

    The random sequential adsorption (RSA) model has served as a paradigm for diverse phenomena in physical chemistry, as well as in other areas such as biology, ecology, and sociology. In the present work, we survey aspects of the RSA model with emphasis on the approach to and properties of jammed states obtained for large times in continuum deposition versus that on lattice substrates, and on pre-patterned surfaces. The latter model has been of recent interest in the context of efforts to use pre-patterning as a tool to improve self-assembly in micro- and nanoscale surface structure engineering

  3. Exploiting Sequential Patterns Found in Users' Solutions and Virtual Tutor Behavior to Improve Assistance in ITS

    Science.gov (United States)

    Fournier-Viger, Philippe; Faghihi, Usef; Nkambou, Roger; Nguifo, Engelbert Mephu

    2010-01-01

    We propose to mine temporal patterns in Intelligent Tutoring Systems (ITSs) to uncover useful knowledge that can enhance their ability to provide assistance. To discover patterns, we suggest using a custom, sequential pattern-mining algorithm. Two ways of applying the algorithm to enhance an ITS's capabilities are addressed. The first is to…

  4. Efficient Mining and Detection of Sequential Intrusion Patterns for Network Intrusion Detection Systems

    Science.gov (United States)

    Shyu, Mei-Ling; Huang, Zifang; Luo, Hongli

    In recent years, pervasive computing infrastructures have greatly improved the interaction between human and system. As we put more reliance on these computing infrastructures, we also face threats of network intrusion and/or any new forms of undesirable IT-based activities. Hence, network security has become an extremely important issue, which is closely connected with homeland security, business transactions, and people's daily life. Accurate and efficient intrusion detection technologies are required to safeguard the network systems and the critical information transmitted in the network systems. In this chapter, a novel network intrusion detection framework for mining and detecting sequential intrusion patterns is proposed. The proposed framework consists of a Collateral Representative Subspace Projection Modeling (C-RSPM) component for supervised classification, and an inter-transactional association rule mining method based on Layer Divided Modeling (LDM) for temporal pattern analysis. Experiments on the KDD99 data set and the traffic data set generated by a private LAN testbed show promising results with high detection rates, low processing time, and low false alarm rates in mining and detecting sequential intrusion detections.

  5. Deep Learning For Sequential Pattern Recognition

    OpenAIRE

    Safari, Pooyan

    2013-01-01

    Projecte realitzat en el marc d’un programa de mobilitat amb la Technische Universität München (TUM) In recent years, deep learning has opened a new research line in pattern recognition tasks. It has been hypothesized that this kind of learning would capture more abstract patterns concealed in data. It is motivated by the new findings both in biological aspects of the brain and hardware developments which have made the parallel processing possible. Deep learning methods come along with ...

  6. Sequential analysis of CT findings in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Kawamura, Mitsuru; Tokumaru, Yukio; Ito, Naoki; Yamada, Tatsuo; Hirayama, Keizo

    1982-01-01

    CT findings of six patients with serologically confirmed herpes simplex encephalitis were analyzed sequentially. The initial change in CT scan in 3 cases was generalized cerebral edema instead of low density areas in the anterior temporal lobes, which have generally been known as the initial findings. Then, bilateral (5 cases) or unilateral (1 case) island-shaped low absorption areas in the insular cortex and the claustrum appeared within 10 days of onset in all 6 cases. These findings, especially the latter, seem to be characteristic of the acute stage and useful in the early diagnosis of herpes simplex encephalitis. The low density areas, then, spread to the temporal lobes, rectal and cingulate gyri in the subacute stage (3 cases) and finally to the frontal and occipital lobes in the chronic stage (2 cases). In the basal ganglia, thalamus, brain stem and cerebellum, however, there were no low density areas. In 2 cases there was no progression of low density areas beyond those of the acute stage. In one case there were high density areas in the temporal lobes and parapontine cisterns bilaterally. This could correspond to the pathological findings in herpes simplex encephalitis. The improvement of CT findings (or arrest at the early stage) was noted in 2 cases in which the clinical state also improved. This might well be the effect of adenine arabinoside. The one case treated with cytosine arabinoside had extensive low density areas in CT and finally died. The importance of CT in the evaluation of adenine arabinoside therapy was stressed. (author)

  7. Mining compressing sequential problems

    NARCIS (Netherlands)

    Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

    2012-01-01

    Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

  8. Acute hydrocarbon pneumonia after white spirit aspiration: sequential HRCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Facon, David; Coumbaras, Jean; Bigot, Emmanuelle; Bahlouli, Fouad; Bellin, Marie-France [Universite Paris 11, Department of Radiology, Hopital Paul-Brousse, AP-HP, Villejuif Cedex (France); Boissonnas, Alain [Universite Paris 11, Department of Internal Medicine, Hopital Paul-Brousse, AP-HP, Villejuif Cedex (France)

    2005-01-01

    Hydrocarbon pneumonia is a very uncommon condition resulting from aspiration of mineral oil into the lung. We report the first description of early and sequential high-resolution computed tomographic (HRCT) findings of hydrocarbon pneumonia following attempted suicide by white spirit aspiration. Initial HRCT showed patchy opacities of coalescing masses with well-defined walls. They were visible in the middle lobe, lingula and lower lobes. Follow-up CT showed regression of the alveolar opacities, the presence of pneumatoceles and right asymptomatic pneumothorax. After 23 months of follow-up, the patient remained asymptomatic, and the follow-up CT scan was considered normal. The radiological features and a review of the relevant literature are briefly discussed. (orig.)

  9. [Sequential prescriptions: Arguments for a change of therapeutic patterns in treatment resistant depressions].

    Science.gov (United States)

    Allouche, G

    2016-02-01

    Among the therapeutic strategies in treatment of resistant depression, the use of sequential prescriptions is discussed here. A number of observations, initially quite isolated and few controlled studies, some large-scale, have been reported, which showed a definite therapeutic effect of certain requirements in sequential treatment of depression. The Sequenced Treatment Alternatives to Relieve Depression Study (STAR*D) is up to now the largest clinical trial exploring treatment strategies in non psychotic resistant depression in real-life conditions with an algorithm of sequential decision. The main conclusions of this study are the following: after two unsuccessful attempts, the chance of remission decreases considerably. A 12-months follow-up showed that the higher the use of the processing steps were high, the more common the relapses were during this period. The pharmacological differences between psychotropic did not cause clinically significant difference. The positive effect of lithium in combination with antidepressants has been known since the work of De Montigny. Antidepressants allow readjustment of physiological sequence involving different monoaminergic systems together. Studies with tricyclic antidepressant-thyroid hormone T3: in depression, decreased norepinephrine at the synaptic receptors believed to cause hypersensitivity of these receptors. Thyroid hormones modulate the activity of adrenergic receptors. There would be a balance of activity between alpha and beta-adrenergic receptors, depending on the bioavailability of thyroid hormones. ECT may in some cases promote pharmacological response in case of previous resistance, or be effective in preventing relapse. Cognitive therapy and antidepressant medications likely have an effect on different types of depression. We can consider the interest of cognitive therapy in a sequential pattern after effective treatment with an antidepressant effect for treatment of residual symptoms, preventing relapses

  10. The sequential structure of brain activation predicts skill.

    Science.gov (United States)

    Anderson, John R; Bothell, Daniel; Fincham, Jon M; Moon, Jungaa

    2016-01-29

    In an fMRI study, participants were trained to play a complex video game. They were scanned early and then again after substantial practice. While better players showed greater activation in one region (right dorsal striatum) their relative skill was better diagnosed by considering the sequential structure of whole brain activation. Using a cognitive model that played this game, we extracted a characterization of the mental states that are involved in playing a game and the statistical structure of the transitions among these states. There was a strong correspondence between this measure of sequential structure and the skill of different players. Using multi-voxel pattern analysis, it was possible to recognize, with relatively high accuracy, the cognitive states participants were in during particular scans. We used the sequential structure of these activation-recognized states to predict the skill of individual players. These findings indicate that important features about information-processing strategies can be identified from a model-based analysis of the sequential structure of brain activation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. C-quence: a tool for analyzing qualitative sequential data.

    Science.gov (United States)

    Duncan, Starkey; Collier, Nicholson T

    2002-02-01

    C-quence is a software application that matches sequential patterns of qualitative data specified by the user and calculates the rate of occurrence of these patterns in a data set. Although it was designed to facilitate analyses of face-to-face interaction, it is applicable to any data set involving categorical data and sequential information. C-quence queries are constructed using a graphical user interface. The program does not limit the complexity of the sequential patterns specified by the user.

  12. Sequential changes in histologic pattern and extracellular matrix deposition during the healing of chronic venous ulcers.

    OpenAIRE

    Herrick, S. E.; Sloan, P.; McGurk, M.; Freak, L.; McCollum, C. N.; Ferguson, M. W.

    1992-01-01

    As part of a major clinical trial, sequential biopsies were taken from the margins of venous leg ulcers during their healing. The changing patterns of tissue architecture and extracellular matrix synthesis during healing were documented histologically and immunocytochemically. Initial biopsies were similar in appearance: prominent fibrin cuffs, variable inflammation, hemosiderin, and red blood cell extravasation. So called "fibrin cuffs" were highly organized structures composed of laminin, f...

  13. Kajian Algoritma Sequential Pattern Mining Dan Market Basket Analysis Dalam Pengenalan Pola Belanja Customer Untuk Layout Toko

    Directory of Open Access Journals (Sweden)

    Rusito Rusito

    2016-01-01

    Full Text Available Penelitian ini membahas tentang keterkaitan antar item yang dibeli oleh customer dalam toko ritel. Pengetahuan keterkaitan item yang dibeli dapat digunakan untuk  menentukan tata letak barang dagangan toko ritel. Hal ini penting agar konsumen dapat mudah mendapatkan barang yang dibutuhkan. Sehingga dapat meningkatkan omzet penjualan toko ritel sehingga akhirnya menambah keuntungan bagi pemilik toko ritel. Teknik yang digunakan untuk menyelesaikan penggalian data dan keterkaitan pembelian tersebut menggunakan pendekatan Association rule dan Market Basket Analysis. Sedangkan untuk mencari keterkaitan item tersebut digunakan algoritma Sequential Pattern Mining. Digunakan karena mampu menangani jumlah database yang besar dan sangat baik disisi kecepatan pemrosesan. Berbagai aplikasi telah diidentifikasi, termasuk misalnya, cross-selling, analisis situs Web, pendukung keputusan, evaluasi kredit, acara prediksi kriminal, analisis perilaku pelanggan  dan deteksi penipuan. Dari penelitian yang telah dilakukan diperoleh  pola-pola belanja customer untuk membentuk suatu layout display dalam toko ritel. Penelitian ini juga menyajikan suatu kerja algoritma yang lebih efektif dari algoritma asli karena terdapat pembatasan perulangan. Untuk kombinasi maksimal 5 item dengan waktu eksekusi 421.06 detik untuk 200 nota.   Kata kunci : Data Mining, Algoritma Sequential Pattern Mining, Market Basket Analysis, Apriori, Layout, Toko Ritel

  14. Time-sequential observation of spindle and phragmoplast orientation in BY-2 cells with altered cortical actin microfilament patterning.

    Science.gov (United States)

    Kojo, Kei H; Yasuhara, Hiroki; Hasezawa, Seiichiro

    2014-01-01

    Precise division plane determination is essential for plant development. At metaphase, a dense actin microfilament meshwork appears on both sides of the cell center, forming a characteristic cortical actin microfilament twin peak pattern in BY-2 cells. We previously reported a strong correlation between altered cortical actin microfilament patterning and an oblique mitotic spindle orientation, implying that these actin microfilament twin peaks play a role in the regulation of mitotic spindle orientation. In the present study, time-sequential observation was used to reveal the progression from oblique phragmoplast to oblique cell plate orientation in cells with altered cortical actin microfilament patterning. In contrast to cells with normal actin microfilament twin peaks, oblique phragmoplast reorientation was rarely observed in cells with altered cortical actin microfilament patterning. These results support the important roles of cortical actin microfilament patterning in division plane orientation.

  15. Retrieval of sea surface velocities using sequential ocean colour monitor (OCM) data

    Digital Repository Service at National Institute of Oceanography (India)

    Prasad, J.S.; Rajawat, A.S.; Pradhan, Y.; Chauhan, O.S.; Nayak, S.R.

    velocities has been developed. The method is based on matching suspended sediment dispersion patterns, in sequential two time lapsed images. The pattern matching is performed on atmospherically corrected and geo-referenced sequential pair of images by Maximum...

  16. Correlation of sequential MR imaging of the injured spinal cord with prognosis

    International Nuclear Information System (INIS)

    Takahashi, Mutsumasa; Izunaga, Hiroshi; Sato, Ryuichiro; Shinzato, Jintetsu; Korogi, Yukunori; Yamashita, Yasuyuki; Sakae, Terumi

    1993-01-01

    Forty-nine patients with acute spinal cord injuries were studied sequentially with MR imaging by using 0.5 Tesla superconductive units, and sequential MR changes were correlated with the prognosis of the patients. MR images were obtained within one week of the injury and then every two to six months when possible. The Frankel classification of neurologic function was correlated with MR findings. The most frequently observed types of signal intensity patterns on MR imaging were type 0 (isointensity on both T 1 - and T 2 -weighted images) and type I (isointensity on T 1 - and hyperintensity on T 2 -weighted images). In subsequent subacute and chronic stages, type II (hypointensity on T 1 and hyperintensity on T 2 ) was most frequently observed. The evolution of type 0 was to types I and II, whereas type I usually turned into type II or remained as type I. Type III (hyperintensity on T 1 and hyper-, iso- or hypointensity on T 2 images) patients were few in number. There was a good correlation between MR imaging patterns and neurologic recovery for initial and subsequent MR patterns, in that type 0 showed good recovery, whereas types I and II revealed good improvement or no recovery. In addition, the extent of the high signal intensity area on initial as well as on subsequent T 2 -weighted images was proportionally correlated to neurologic recovery. The degree of cord compression was also important for predicting recovery of neurologic function. Findings of MR imaging of acutely injured spinal cord suggested the prognosis of spinal cord injury, especially when sequential studies were obtained. (author)

  17. Sequential response patterns to chemotherapy and radiotherapy in head and neck cancer

    International Nuclear Information System (INIS)

    Hong, W.K.; O'Donoghue, G.M.; Sheetz, S.

    1985-01-01

    Surgery and/or radiotherapy have been the standard therapies for locally advanced squamous cell carcinoma of the head and neck region. Despite major improvement in these therapeutic techniques, the control rate in cases of advanced cancer remains poor. More recently, induction chemotherapy as initial treatment has been used in previously untreated squamous cell carcinoma of the head and neck. For the last 6 years at the Boston Veterans Administration (V.A.) Medical Center, initial induction chemotherapy followed by surgery and/or radiotherapy has been employed in the treatment of advanced head and neck cancer. The use of chemotherapy and radiotherapy has allowed the authors to monitor and correlate sequential response patterns produced by each modality of treatment. The authors have observed that responders to chemotherapy can be predicted to have further response to subsequent radiotherapy

  18. Eyewitness confidence in simultaneous and sequential lineups: a criterion shift account for sequential mistaken identification overconfidence.

    Science.gov (United States)

    Dobolyi, David G; Dodson, Chad S

    2013-12-01

    Confidence judgments for eyewitness identifications play an integral role in determining guilt during legal proceedings. Past research has shown that confidence in positive identifications is strongly associated with accuracy. Using a standard lineup recognition paradigm, we investigated accuracy using signal detection and ROC analyses, along with the tendency to choose a face with both simultaneous and sequential lineups. We replicated past findings of reduced rates of choosing with sequential as compared to simultaneous lineups, but notably found an accuracy advantage in favor of simultaneous lineups. Moreover, our analysis of the confidence-accuracy relationship revealed two key findings. First, we observed a sequential mistaken identification overconfidence effect: despite an overall reduction in false alarms, confidence for false alarms that did occur was higher with sequential lineups than with simultaneous lineups, with no differences in confidence for correct identifications. This sequential mistaken identification overconfidence effect is an expected byproduct of the use of a more conservative identification criterion with sequential than with simultaneous lineups. Second, we found a steady drop in confidence for mistaken identifications (i.e., foil identifications and false alarms) from the first to the last face in sequential lineups, whereas confidence in and accuracy of correct identifications remained relatively stable. Overall, we observed that sequential lineups are both less accurate and produce higher confidence false identifications than do simultaneous lineups. Given the increasing prominence of sequential lineups in our legal system, our data argue for increased scrutiny and possibly a wholesale reevaluation of this lineup format. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  19. Endogenous sequential cortical activity evoked by visual stimuli.

    Science.gov (United States)

    Carrillo-Reid, Luis; Miller, Jae-Eun Kang; Hamm, Jordan P; Jackson, Jesse; Yuste, Rafael

    2015-06-10

    Although the functional properties of individual neurons in primary visual cortex have been studied intensely, little is known about how neuronal groups could encode changing visual stimuli using temporal activity patterns. To explore this, we used in vivo two-photon calcium imaging to record the activity of neuronal populations in primary visual cortex of awake mice in the presence and absence of visual stimulation. Multidimensional analysis of the network activity allowed us to identify neuronal ensembles defined as groups of cells firing in synchrony. These synchronous groups of neurons were themselves activated in sequential temporal patterns, which repeated at much higher proportions than chance and were triggered by specific visual stimuli such as natural visual scenes. Interestingly, sequential patterns were also present in recordings of spontaneous activity without any sensory stimulation and were accompanied by precise firing sequences at the single-cell level. Moreover, intrinsic dynamics could be used to predict the occurrence of future neuronal ensembles. Our data demonstrate that visual stimuli recruit similar sequential patterns to the ones observed spontaneously, consistent with the hypothesis that already existing Hebbian cell assemblies firing in predefined temporal sequences could be the microcircuit substrate that encodes visual percepts changing in time. Copyright © 2015 Carrillo-Reid et al.

  20. Sequential, progressive, equal-power, reflective beam-splitter arrays

    Science.gov (United States)

    Manhart, Paul K.

    2017-11-01

    The equations to calculate equal-power reflectivity of a sequential series of beam splitters is presented. Non-sequential optical design examples are offered for uniform illumination using diode lasers. Objects created using Boolean operators and Swept Surfaces can create objects capable of reflecting light into predefined elevation and azimuth angles. Analysis of the illumination patterns for the array are also presented.

  1. Imitation of the sequential structure of actions by chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Whiten, A

    1998-09-01

    Imitation was studied experimentally by allowing chimpanzees (Pan troglodytes) to observe alternative patterns of actions for opening a specially designed "artificial fruit." Like problematic foods primates deal with naturally, with the test fruit several defenses had to be removed to gain access to an edible core, but the sequential order and method of defense removal could be systematically varied. Each subject repeatedly observed 1 of 2 alternative techniques for removing each defense and 1 of 2 alternative sequential patterns of defense removal. Imitation of sequential organization emerged after repeated cycles of demonstration and attempts at opening the fruit. Imitation in chimpanzees may thus have some power to produce cultural convergence, counter to the supposition that individual learning processes corrupt copied actions. Imitation of sequential organization was accompanied by imitation of some aspects of the techniques that made up the sequence.

  2. Judgments relative to patterns: how temporal sequence patterns affect judgments and memory.

    Science.gov (United States)

    Kusev, Petko; Ayton, Peter; van Schaik, Paul; Tsaneva-Atanasova, Krasimira; Stewart, Neil; Chater, Nick

    2011-12-01

    Six experiments studied relative frequency judgment and recall of sequentially presented items drawn from 2 distinct categories (i.e., city and animal). The experiments show that judged frequencies of categories of sequentially encountered stimuli are affected by certain properties of the sequence configuration. We found (a) a first-run effect whereby people overestimated the frequency of a given category when that category was the first repeated category to occur in the sequence and (b) a dissociation between judgments and recall; respondents may judge 1 event more likely than the other and yet recall more instances of the latter. Specifically, the distribution of recalled items does not correspond to the frequency estimates for the event categories, indicating that participants do not make frequency judgments by sampling their memory for individual items as implied by other accounts such as the availability heuristic (Tversky & Kahneman, 1973) and the availability process model (Hastie & Park, 1986). We interpret these findings as reflecting the operation of a judgment heuristic sensitive to sequential patterns and offer an account for the relationship between memory and judged frequencies of sequentially encountered stimuli.

  3. A sequential/parallel track selector

    CERN Document Server

    Bertolino, F; Bressani, Tullio; Chiavassa, E; Costa, S; Dellacasa, G; Gallio, M; Musso, A

    1980-01-01

    A medium speed ( approximately 1 mu s) hardware pre-analyzer for the selection of events detected in four planes of drift chambers in the magnetic field of the Omicron Spectrometer at the CERN SC is described. Specific geometrical criteria determine patterns of hits in the four planes of vertical wires that have to be recognized and that are stored as patterns of '1's in random access memories. Pairs of good hits are found sequentially, then the RAMs are used as look-up tables. (6 refs).

  4. Temporal integration of sequential auditory events: silent period in sound pattern activates human planum temporale.

    Science.gov (United States)

    Mustovic, Henrietta; Scheffler, Klaus; Di Salle, Francesco; Esposito, Fabrizio; Neuhoff, John G; Hennig, Jürgen; Seifritz, Erich

    2003-09-01

    Temporal integration is a fundamental process that the brain carries out to construct coherent percepts from serial sensory events. This process critically depends on the formation of memory traces reconciling past with present events and is particularly important in the auditory domain where sensory information is received both serially and in parallel. It has been suggested that buffers for transient auditory memory traces reside in the auditory cortex. However, previous studies investigating "echoic memory" did not distinguish between brain response to novel auditory stimulus characteristics on the level of basic sound processing and a higher level involving matching of present with stored information. Here we used functional magnetic resonance imaging in combination with a regular pattern of sounds repeated every 100 ms and deviant interspersed stimuli of 100-ms duration, which were either brief presentations of louder sounds or brief periods of silence, to probe the formation of auditory memory traces. To avoid interaction with scanner noise, the auditory stimulation sequence was implemented into the image acquisition scheme. Compared to increased loudness events, silent periods produced specific neural activation in the right planum temporale and temporoparietal junction. Our findings suggest that this area posterior to the auditory cortex plays a critical role in integrating sequential auditory events and is involved in the formation of short-term auditory memory traces. This function of the planum temporale appears to be fundamental in the segregation of simultaneous sound sources.

  5. Basal ganglia and cortical networks for sequential ordering and rhythm of complex movements

    Directory of Open Access Journals (Sweden)

    Jeffery G. Bednark

    2015-07-01

    Full Text Available Voluntary actions require the concurrent engagement and coordinated control of complex temporal (e.g. rhythm and ordinal motor processes. Using high-resolution functional magnetic resonance imaging (fMRI and multi-voxel pattern analysis (MVPA, we sought to determine the degree to which these complex motor processes are dissociable in basal ganglia and cortical networks. We employed three different finger-tapping tasks that differed in the demand on the sequential temporal rhythm or sequential ordering of submovements. Our results demonstrate that sequential rhythm and sequential order tasks were partially dissociable based on activation differences. The sequential rhythm task activated a widespread network centered around the SMA and basal-ganglia regions including the dorsomedial putamen and caudate nucleus, while the sequential order task preferentially activated a fronto-parietal network. There was also extensive overlap between sequential rhythm and sequential order tasks, with both tasks commonly activating bilateral premotor, supplementary motor, and superior/inferior parietal cortical regions, as well as regions of the caudate/putamen of the basal ganglia and the ventro-lateral thalamus. Importantly, within the cortical regions that were active for both complex movements, MVPA could accurately classify different patterns of activation for the sequential rhythm and sequential order tasks. In the basal ganglia, however, overlapping activation for the sequential rhythm and sequential order tasks, which was found in classic motor circuits of the putamen and ventro-lateral thalamus, could not be accurately differentiated by MVPA. Overall, our results highlight the convergent architecture of the motor system, where complex motor information that is spatially distributed in the cortex converges into a more compact representation in the basal ganglia.

  6. Sequential contrast-enhanced MR imaging of the penis.

    Science.gov (United States)

    Kaneko, K; De Mouy, E H; Lee, B E

    1994-04-01

    To determine the enhancement patterns of the penis at magnetic resonance (MR) imaging. Sequential contrast material-enhanced MR images of the penis in a flaccid state were obtained in 16 volunteers (12 with normal penile function and four with erectile dysfunction). Subjects with normal erectile function showed gradual and centrifugal enhancement of the corpora cavernosa, while those with erectile dysfunction showed poor enhancement with abnormal progression. Sequential contrast-enhanced MR imaging provides additional morphologic information for the evaluation of erectile dysfunction.

  7. Efficient constraint-based Sequential Pattern Mining (SPM algorithm to understand customers’ buying behaviour from time stamp-based sequence dataset

    Directory of Open Access Journals (Sweden)

    Niti Ashish Kumar Desai

    2015-12-01

    Full Text Available Business Strategies are formulated based on an understanding of customer needs. This requires development of a strategy to understand customer behaviour and buying patterns, both current and future. This involves understanding, first how an organization currently understands customer needs and second predicting future trends to drive growth. This article focuses on purchase trend of customer, where timing of purchase is more important than association of item to be purchased, and which can be found out with Sequential Pattern Mining (SPM methods. Conventional SPM algorithms worked purely on frequency identifying patterns that were more frequent but suffering from challenges like generation of huge number of uninteresting patterns, lack of user’s interested patterns, rare item problem, etc. Article attempts a solution through development of a SPM algorithm based on various constraints like Gap, Compactness, Item, Recency, Profitability and Length along with Frequency constraint. Incorporation of six additional constraints is as well to ensure that all patterns are recently active (Recency, active for certain time span (Compactness, profitable and indicative of next timeline for purchase (Length―Item―Gap. The article also attempts to throw light on how proposed Constraint-based Prefix Span algorithm is helpful to understand buying behaviour of customer which is in formative stage.

  8. Finding purchase activity patterns in small & medium enterprises

    NARCIS (Netherlands)

    Vegter, Geert J.

    2015-01-01

    Finding purchase activity patterns in Small & Medium Enterprises in a research program to enable SMEs to improve their purchase and company performance. Posterpresentatie KCO conferentie, 16 november 2015.

  9. Multichannel, sequential or combined X-ray spectrometry

    International Nuclear Information System (INIS)

    Florestan, J.

    1979-01-01

    X-ray spectrometer qualities and defects are evaluated for sequential and multichannel categories. Multichannel X-ray spectrometer has time-coherency advantage and its results could be more reproducible; on the other hand some spatial incoherency limits low percentage and traces applications, specially when backgrounds are very variable. In this last case, sequential X-ray spectrometer would find again great usefulness [fr

  10. Localization Using Magnetic Patterns for Autonomous Mobile Robot

    Directory of Open Access Journals (Sweden)

    Won Suk You

    2014-03-01

    Full Text Available In this paper, we present a method of localization using magnetic landmarks. With this method, it is possible to compensate the pose error (xe, ye, θe of a mobile robot correctly and localize its current position on a global coordinate system on the surface of a structured environment with magnetic landmarks. A set of four magnetic bars forms total six different patterns of landmarks and these patterns can be read by the mobile robot with magnetic hall sensors. A sequential motion strategy for a mobile robot is proposed to find the geometric center of magnetic landmarks by reading the nonlinear magnetic field. The mobile robot first moves into the center region of the landmark where it can read the magnetic pattern, after which tracking and global localization can be easily achieved by recognizing the patterns of neighboring landmarks. Experimental results show the effectiveness of the sequential motion strategy for estimating the center of the first encountered landmark as well as the performance of tracking and global localization of the proposed system.

  11. Retrieval of sea surface velocities using sequential Ocean Colour ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    pended sediment dispersion patterns, in sequential two time lapsed images. .... face advective velocities consists essentially of iden- tifying the ... matrix is time consuming, a significant reduction .... Chauhan, P. 2002 Personal Communication.

  12. A real-time comparison between direct control, sequential pattern recognition control and simultaneous pattern recognition control using a Fitts' law style assessment procedure.

    Science.gov (United States)

    Wurth, Sophie M; Hargrove, Levi J

    2014-05-30

    Pattern recognition (PR) based strategies for the control of myoelectric upper limb prostheses are generally evaluated through offline classification accuracy, which is an admittedly useful metric, but insufficient to discuss functional performance in real time. Existing functional tests are extensive to set up and most fail to provide a challenging, objective framework to assess the strategy performance in real time. Nine able-bodied and two amputee subjects gave informed consent and participated in the local Institutional Review Board approved study. We designed a two-dimensional target acquisition task, based on the principles of Fitts' law for human motor control. Subjects were prompted to steer a cursor from the screen center of into a series of subsequently appearing targets of different difficulties. Three cursor control systems were tested, corresponding to three electromyography-based prosthetic control strategies: 1) amplitude-based direct control (the clinical standard of care), 2) sequential PR control, and 3) simultaneous PR control, allowing for a concurrent activation of two degrees of freedom (DOF). We computed throughput (bits/second), path efficiency (%), reaction time (second), and overshoot (%)) and used general linear models to assess significant differences between the strategies for each metric. We validated the proposed methodology by achieving very high coefficients of determination for Fitts' law. Both PR strategies significantly outperformed direct control in two-DOF targets and were more intuitive to operate. In one-DOF targets, the simultaneous approach was the least precise. The direct control was efficient in one-DOF targets but cumbersome to operate in two-DOF targets through a switch-depended sequential cursor control. We designed a test, capable of comprehensively describing prosthetic control strategies in real time. When implemented on control subjects, the test was able to capture statistically significant differences (p

  13. Cross-correlation patterns in social opinion formation with sequential data

    Science.gov (United States)

    Chakrabarti, Anindya S.

    2016-11-01

    Recent research on large-scale internet data suggests existence of patterns in the collective behavior of billions of people even though each of them may pursue own activities. In this paper, we interpret online rating activity as a process of forming social opinion about individual items, where people sequentially choose a rating based on the current information set comprising all previous ratings and own preferences. We construct an opinion index from the sequence of ratings and we show that (1) movie-specific opinion converges much slower than an independent and identically distributed (i.i.d.) sequence of ratings, (2) rating sequence for individual movies shows lesser variation compared to an i.i.d. sequence of ratings, (3) the probability density function of the asymptotic opinions has more spread than that defined over opinion arising from i.i.d. sequence of ratings, (4) opinion sequences across movies are correlated with significantly higher and lower correlation compared to opinion constructed from i.i.d. sequence of ratings, creating a bimodal cross-correlation structure. By decomposing the temporal correlation structures from panel data of movie ratings, we show that the social effects are very prominent whereas group effects cannot be differentiated from those of surrogate data and individual effects are quite small. The former explains a large part of extreme positive or negative correlations between sequences of opinions. In general, this method can be applied to any rating data to extract social or group-specific effects in correlation structures. We conclude that in this particular case, social effects are important in opinion formation process.

  14. Sequential Pattern Mining of Electronic Healthcare Reimbursement Claims: Experiences and Challenges in Uncovering How Patients are Treated by Physicians

    Energy Technology Data Exchange (ETDEWEB)

    Pullum, Laura L [ORNL; Ramanathan, Arvind [ORNL; Hobson, Tanner C [ORNL

    2015-01-01

    We examine the use of electronic healthcare reimbursement claims (EHRC) for analyzing healthcare delivery and practice patterns across the United States (US). We show that EHRCs are correlated with disease incidence estimates published by the Centers for Disease Control. Further, by analyzing over 1 billion EHRCs, we track patterns of clinical procedures administered to patients with autism spectrum disorder (ASD), heart disease (HD) and breast cancer (BC) using sequential pattern mining algorithms. Our analyses reveal that in contrast to treating HD and BC, clinical procedures for ASD diagnoses are highly varied leading up to and after the ASD diagnoses. The discovered clinical procedure sequences also reveal significant differences in the overall costs incurred across different parts of the US, indicating a lack of consensus amongst practitioners in treating ASD patients. We show that a data-driven approach to understand clinical trajectories using EHRC can provide quantitative insights into how to better manage and treat patients. Based on our experience, we also discuss emerging challenges in using EHRC datasets for gaining insights into the state of contemporary healthcare delivery and practice in the US.

  15. The Pattern of Hysterosalpingographic Findings in Women Being ...

    African Journals Online (AJOL)

    Background: Tubal occlusion is the commonest cause of female infertility in the developing societies. Hysterosalpingography remains a vital method of assessing tubal patency especially in resource limited settings such as ours. Objective: To review the pattern of hysterosalpingographic findings among women being ...

  16. Personal continuous route pattern mining

    Institute of Scientific and Technical Information of China (English)

    Qian YE; Ling CHEN; Gen-cai CHEN

    2009-01-01

    In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

  17. Evaluation of physiological and behavioral measures in relation to dental anxiety during sequential dental visits in children

    Directory of Open Access Journals (Sweden)

    Rayen R

    2006-01-01

    Full Text Available Anxiety is a special variety of fear, experienced in anticipation of threatening stimuli. While some research workers have said that the response of a child improves with the number of visits, many have felt otherwise. The present study is yet another effort to find the patterns of anxiety in children during sequential dental visits. The main aim was to determine the physiological and behavioral variations during sequential dental visits and its impact on age and sex. The study was conducted at the outpatient Department of Pedodontics and preventive dentistry, Meenakshi Ammal Dental College and Hospital, Chennai to evaluate the physiological and behavioural measures of stress and anxiety in children. One hundred and fifteen children, between four and eleven years of age who reported for dental treatment were selected for the study.

  18. Comparisons of memory for nonverbal auditory and visual sequential stimuli.

    Science.gov (United States)

    McFarland, D J; Cacace, A T

    1995-01-01

    Properties of auditory and visual sensory memory were compared by examining subjects' recognition performance of randomly generated binary auditory sequential frequency patterns and binary visual sequential color patterns within a forced-choice paradigm. Experiment 1 demonstrated serial-position effects in auditory and visual modalities consisting of both primacy and recency effects. Experiment 2 found that retention of auditory and visual information was remarkably similar when assessed across a 10s interval. Experiments 3 and 4, taken together, showed that the recency effect in sensory memory is affected more by the type of response required (recognition vs. reproduction) than by the sensory modality employed. These studies suggest that auditory and visual sensory memory stores for nonverbal stimuli share similar properties with respect to serial-position effects and persistence over time.

  19. Managerial adjustment and its limits: sequential fault in comparative perspective

    Directory of Open Access Journals (Sweden)

    Flávio da Cunha Rezende

    2008-01-01

    Full Text Available This article focuses on explanations for sequential faults in administrative reform. It deals with the limits of managerial adjustment in an approach that attempts to connect theory and empirical data, articulating three levels of analysis. The first level presents comparative evidence of sequential fault within reforms in national governments through a set of indicators geared toward understanding changes in the role of the state. In light of analyses of a representative set of comparative studies on reform implementation, the second analytical level proceeds to identify four typical mechanisms that are present in explanations on managerial adjustment faults. In this way, we seek to configure an explanatory matrix for theories on sequential fault. Next we discuss the experience of management reform in the Brazilian context, conferring special attention on one of the mechanisms that creates fault: the control dilemma. The major hypotheses that guide our article are that reforms lead to sequential fault and that there are at least four causal mechanisms that produce reforms: a transactions costs involved in producing reforms; b performance legacy; c predominance of fiscal adjustment and d the control dilemma. These mechanisms act separately or in concert, and act to decrease chances for a transformation of State managerial patterns. Major evidence that is analyzed in these articles lend consistency to the general argument that reforms have failed in their attempts to reduce public expenses, alter patterns of resource allocation, reduce the labor force and change the role of the State. Our major conclusion is that reforms fail sequentially and managerial adjustment displays considerable limitations, particularly those of a political nature.

  20. The target-to-foils shift in simultaneous and sequential lineups.

    Science.gov (United States)

    Clark, Steven E; Davey, Sherrie L

    2005-04-01

    A theoretical cornerstone in eyewitness identification research is the proposition that witnesses, in making decisions from standard simultaneous lineups, make relative judgments. The present research considers two sources of support for this proposal. An experiment by G. L. Wells (1993) showed that if the target is removed from a lineup, witnesses shift their responses to pick foils, rather than rejecting the lineups, a result we will term a target-to-foils shift. Additional empirical support is provided by results from sequential lineups which typically show higher accuracy than simultaneous lineups, presumably because of a decrease in the use of relative judgments in making identification decisions. The combination of these two lines of research suggests that the target-to-foils shift should be reduced in sequential lineups relative to simultaneous lineups. Results of two experiments showed an overall advantage for sequential lineups, but also showed a target-to-foils shift equal in size for simultaneous and sequential lineups. Additional analyses indicated that the target-to-foils shift in sequential lineups was moderated in part by an order effect and was produced with (Experiment 2) or without (Experiment 1) a shift in decision criterion. This complex pattern of results suggests that more work is needed to understand the processes which underlie decisions in simultaneous and sequential lineups.

  1. Computing Sequential Equilibria for Two-Player Games

    DEFF Research Database (Denmark)

    Miltersen, Peter Bro; Sørensen, Troels Bjerre

    2006-01-01

    Koller, Megiddo and von Stengel showed how to efficiently compute minimax strategies for two-player extensive-form zero-sum games with imperfect information but perfect recall using linear programming and avoiding conversion to normal form. Koller and Pfeffer pointed out that the strategies...... obtained by the algorithm are not necessarily sequentially rational and that this deficiency is often problematic for the practical applications. We show how to remove this deficiency by modifying the linear programs constructed by Koller, Megiddo and von Stengel so that pairs of strategies forming...... a sequential equilibrium are computed. In particular, we show that a sequential equilibrium for a two-player zero-sum game with imperfect information but perfect recall can be found in polynomial time. In addition, the equilibrium we find is normal-form perfect. Our technique generalizes to general-sum games...

  2. Radiologic findings of diffuse Pulmonary hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Mi Ra; Song, Koun Sik; Lee, Jin Seong; Lim, Tae Hwan [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

    1998-12-01

    To describe the chest radiographic and CT findings of diffuse pulmonary hemorrhage. Two radiologists retrospectively analysed the chest radiographic and CT findings of six patients with diffuse pulmonary hemorrhage. Using open lung biopsy(n=3D2) and transbronchial lung biopsy or bronchoalveolar lavage(n=3D4), diagnosis was based on the presence of hemosiderin-laden macrophage or intra-alveolar hemorrhage. Underlying diseases were Wegener's granulomatosis(n=3D2), antiphospholipid antibody syndrome(n=3D2), Henoch-Schonlein purpura(n=3D1), and idopathic pulmonary hemosiderosis(n=3D1). In all patients, sequential chest radiographs, obtained during a one to six-month period, were available. HRCT scans were obtained in five patinets, and conventional CT scans in one. Follow-up HRCT scans were obtained in two. We also analyzed the patterns of involvement, distribution and sequential changes in the pulmonary abnormalities seen on chest radiographs and CT scans. Chest radiographs showed multifocal patchy consolidation(n=3D6), ground-glass opacity(n=3D3), and multiple granular or nodular opacity(n=3D3). These lesions were intermingled in five patients, while in one there was consolidation only. Sequential chest radiographs demonstrated the improvement of initial pulmonary abnormalities and appearance of new lesions elsewhere within 5-6 days, though within 7-25 (average, 13) days, these had almost normalized. HRCT scans showed patchy consolidation(n=3D5), multiple patchy ground-glass opacity(n=3D5), or ill-defined air space nodules(n=3D4). These lesions were intermingled in five patients, and in one, ground-glass opacity only was noted. In two patients there were interlobular septal thickening and intalobular reticular opacity. The distribution of these abnormalities was almost always bilateral, diffuse with no zonal predominancy, and spared the apex of the lung and subpleural region were less affected. Although chest radiographic and CT findings of diffuse pulmonary

  3. Radiologic findings of diffuse Pulmonary hemorrhage

    International Nuclear Information System (INIS)

    Seo, Mi Ra; Song, Koun Sik; Lee, Jin Seong; Lim, Tae Hwan

    1998-01-01

    To describe the chest radiographic and CT findings of diffuse pulmonary hemorrhage. Two radiologists retrospectively analysed the chest radiographic and CT findings of six patients with diffuse pulmonary hemorrhage. Using open lung biopsy(n=3D2) and transbronchial lung biopsy or bronchoalveolar lavage(n=3D4), diagnosis was based on the presence of hemosiderin-laden macrophage or intra-alveolar hemorrhage. Underlying diseases were Wegener's granulomatosis(n=3D2), antiphospholipid antibody syndrome(n=3D2), Henoch-Schonlein purpura(n=3D1), and idopathic pulmonary hemosiderosis(n=3D1). In all patients, sequential chest radiographs, obtained during a one to six-month period, were available. HRCT scans were obtained in five patinets, and conventional CT scans in one. Follow-up HRCT scans were obtained in two. We also analyzed the patterns of involvement, distribution and sequential changes in the pulmonary abnormalities seen on chest radiographs and CT scans. Chest radiographs showed multifocal patchy consolidation(n=3D6), ground-glass opacity(n=3D3), and multiple granular or nodular opacity(n=3D3). These lesions were intermingled in five patients, while in one there was consolidation only. Sequential chest radiographs demonstrated the improvement of initial pulmonary abnormalities and appearance of new lesions elsewhere within 5-6 days, though within 7-25 (average, 13) days, these had almost normalized. HRCT scans showed patchy consolidation(n=3D5), multiple patchy ground-glass opacity(n=3D5), or ill-defined air space nodules(n=3D4). These lesions were intermingled in five patients, and in one, ground-glass opacity only was noted. In two patients there were interlobular septal thickening and intalobular reticular opacity. The distribution of these abnormalities was almost always bilateral, diffuse with no zonal predominancy, and spared the apex of the lung and subpleural region were less affected. Although chest radiographic and CT findings of diffuse pulmonary

  4. Sequential infiltration synthesis for advanced lithography

    Energy Technology Data Exchange (ETDEWEB)

    Darling, Seth B.; Elam, Jeffrey W.; Tseng, Yu-Chih; Peng, Qing

    2017-10-10

    A plasma etch resist material modified by an inorganic protective component via sequential infiltration synthesis (SIS) and methods of preparing the modified resist material. The modified resist material is characterized by an improved resistance to a plasma etching or related process relative to the unmodified resist material, thereby allowing formation of patterned features into a substrate material, which may be high-aspect ratio features. The SIS process forms the protective component within the bulk resist material through a plurality of alternating exposures to gas phase precursors which infiltrate the resist material. The plasma etch resist material may be initially patterned using photolithography, electron-beam lithography or a block copolymer self-assembly process.

  5. Brick: Mining Pedagogically Interesting Sequential Patterns

    NARCIS (Netherlands)

    Anjewierden, Anjo; Gijlers, Hannie; Saab, Nadira; de Hoog, Robert; Pechenizkiy, Mykola; Calders, Toon; Conati, Cristina; Ventura, Sebastian; Romero, Cristobal; Stamper, John

    2011-01-01

    One of the goals of the SCY project (www.scy-net.eu) is to make (inquiry) learning environments adaptive. The idea is to develop “pedagogical agents” that monitor learner behaviour through the actions they perform and identify patterns that point to systematic behaviour, or lack thereof. To achieve

  6. Visual short-term memory for sequential arrays.

    Science.gov (United States)

    Kumar, Arjun; Jiang, Yuhong

    2005-04-01

    The capacity of visual short-term memory (VSTM) for a single visual display has been investigated in past research, but VSTM for multiple sequential arrays has been explored only recently. In this study, we investigate the capacity of VSTM across two sequential arrays separated by a variable stimulus onset asynchrony (SOA). VSTM for spatial locations (Experiment 1), colors (Experiments 2-4), orientations (Experiments 3 and 4), and conjunction of color and orientation (Experiment 4) were tested, with the SOA across the two sequential arrays varying from 100 to 1,500 msec. We find that VSTM for the trailing array is much better than VSTM for the leading array, but when averaged across the two arrays VSTM has a constant capacity independent of the SOA. We suggest that multiple displays compete for retention in VSTM and that separating information into two temporally discrete groups does not enhance the overall capacity of VSTM.

  7. Lexical decoder for continuous speech recognition: sequential neural network approach

    International Nuclear Information System (INIS)

    Iooss, Christine

    1991-01-01

    The work presented in this dissertation concerns the study of a connectionist architecture to treat sequential inputs. In this context, the model proposed by J.L. Elman, a recurrent multilayers network, is used. Its abilities and its limits are evaluated. Modifications are done in order to treat erroneous or noisy sequential inputs and to classify patterns. The application context of this study concerns the realisation of a lexical decoder for analytical multi-speakers continuous speech recognition. Lexical decoding is completed from lattices of phonemes which are obtained after an acoustic-phonetic decoding stage relying on a K Nearest Neighbors search technique. Test are done on sentences formed from a lexicon of 20 words. The results are obtained show the ability of the proposed connectionist model to take into account the sequentiality at the input level, to memorize the context and to treat noisy or erroneous inputs. (author) [fr

  8. Sequential Coherence in Sentence Pairs Enhances Imagery during Comprehension: An Individual Differences Study.

    Directory of Open Access Journals (Sweden)

    Carol Madden-Lombardi

    Full Text Available The present study investigates how sequential coherence in sentence pairs (events in sequence vs. unrelated events affects the perceived ability to form a mental image of the sentences for both auditory and visual presentations. In addition, we investigated how the ease of event imagery affected online comprehension (word reading times in the case of sequentially coherent and incoherent sentence pairs. Two groups of comprehenders were identified based on their self-reported ability to form vivid mental images of described events. Imageability ratings were higher and faster for pairs of sentences that described events in coherent sequences rather than non-sequential events, especially for high imagers. Furthermore, reading times on individual words suggested different comprehension patterns with respect to sequence coherence for the two groups of imagers, with high imagers activating richer mental images earlier than low imagers. The present results offer a novel link between research on imagery and discourse coherence, with specific contributions to our understanding of comprehension patterns for high and low imagers.

  9. MR findings of chondroblastoma with emphasis on enhancement pattern

    International Nuclear Information System (INIS)

    Oh, Kyung Joong; Go, Sung Hye; Lee, Gyung Kyu; Kim, Jung Eun; Choi, Jung A; Park, Chang Min; Choi, Seung Hong; Kang, Heung Sik; Ahn, Jung Mo; Kim, Sung Moon

    2003-01-01

    To analyze the MR findings of chondroblastoma and peritumoral bone marrow, focussing on the enhancement pattern. Enhanced MR images obtained from 23 patients with pathologically proven chondroblastoma were retrospectively reviewed by three radiologists. The enhancement pattern was classified as one of three types: homogeneous, heterogeneous, or peripheral rim, while peritumoral bone marrow enhancement was assigned one of four grades. Correlation between the enhancement pattern and T2 signal intensity of a tumor was analyzed by fisher's exact test. The enhancement pattern was homogeneous in ten cases, heterogeneous in six, and involved the peripheral rim in seven. In 11 cases, peritumoral bone marrow enhancement was observed. Among the ten instances of homogeneous enhancement the signal intensity seen at T2W1 was homogeneously iso or low in six cases, homogeneously high in two, and heterogeneous in two. Among the seven cases in which three was peripheral rim enhancement, the signal intensity observed at T2W1 was homogeneously high in three, fluid-fluid level in three, and homogeneously iso or low in one. At MR imaging, chondroblastoma shows variable signal intensities and enhancement patterns. The peripheral rim enhancement observed at T2W1 correlated with homogeneously high signal intensity or fluid-fluid levels

  10. MR findings of chondroblastoma with emphasis on enhancement pattern

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Kyung Joong; Go, Sung Hye; Lee, Gyung Kyu; Kim, Jung Eun; Choi, Jung A; Park, Chang Min; Choi, Seung Hong; Kang, Heung Sik [Seoul National University College of Medicine, Seoul (Korea, Republic of); Ahn, Jung Mo [Samsung Medical Center, Seoul (Korea, Republic of); Kim, Sung Moon [Asan Medical Center, Seoul (Korea, Republic of)

    2003-03-01

    To analyze the MR findings of chondroblastoma and peritumoral bone marrow, focussing on the enhancement pattern. Enhanced MR images obtained from 23 patients with pathologically proven chondroblastoma were retrospectively reviewed by three radiologists. The enhancement pattern was classified as one of three types: homogeneous, heterogeneous, or peripheral rim, while peritumoral bone marrow enhancement was assigned one of four grades. Correlation between the enhancement pattern and T2 signal intensity of a tumor was analyzed by fisher's exact test. The enhancement pattern was homogeneous in ten cases, heterogeneous in six, and involved the peripheral rim in seven. In 11 cases, peritumoral bone marrow enhancement was observed. Among the ten instances of homogeneous enhancement the signal intensity seen at T2W1 was homogeneously iso or low in six cases, homogeneously high in two, and heterogeneous in two. Among the seven cases in which three was peripheral rim enhancement, the signal intensity observed at T2W1 was homogeneously high in three, fluid-fluid level in three, and homogeneously iso or low in one. At MR imaging, chondroblastoma shows variable signal intensities and enhancement patterns. The peripheral rim enhancement observed at T2W1 correlated with homogeneously high signal intensity or fluid-fluid levels.

  11. Sequential Power-Dependence Theory

    NARCIS (Netherlands)

    Buskens, Vincent; Rijt, Arnout van de

    2008-01-01

    Existing methods for predicting resource divisions in laboratory exchange networks do not take into account the sequential nature of the experimental setting. We extend network exchange theory by considering sequential exchange. We prove that Sequential Power-Dependence Theory—unlike

  12. Induction of simultaneous and sequential malolactic fermentation in durian wine.

    Science.gov (United States)

    Taniasuri, Fransisca; Lee, Pin-Rou; Liu, Shao-Quan

    2016-08-02

    This study represented for the first time the impact of malolactic fermentation (MLF) induced by Oenococcus oeni and its inoculation strategies (simultaneous vs. sequential) on the fermentation performance as well as aroma compound profile of durian wine. There was no negative impact of simultaneous inoculation of O. oeni and Saccharomyces cerevisiae on the growth and fermentation kinetics of S. cerevisiae as compared to sequential fermentation. Simultaneous MLF did not lead to an excessive increase in volatile acidity as compared to sequential MLF. The kinetic changes of organic acids (i.e. malic, lactic, succinic, acetic and α-ketoglutaric acids) varied with simultaneous and sequential MLF relative to yeast alone. MLF, regardless of inoculation mode, resulted in higher production of fermentation-derived volatiles as compared to control (alcoholic fermentation only), including esters, volatile fatty acids, and terpenes, except for higher alcohols. Most indigenous volatile sulphur compounds in durian were decreased to trace levels with little differences among the control, simultaneous and sequential MLF. Among the different wines, the wine with simultaneous MLF had higher concentrations of terpenes and acetate esters while sequential MLF had increased concentrations of medium- and long-chain ethyl esters. Relative to alcoholic fermentation only, both simultaneous and sequential MLF reduced acetaldehyde substantially with sequential MLF being more effective. These findings illustrate that MLF is an effective and novel way of modulating the volatile and aroma compound profile of durian wine. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Sequential sampling of visual objects during sustained attention.

    Directory of Open Access Journals (Sweden)

    Jianrong Jia

    2017-06-01

    Full Text Available In a crowded visual scene, attention must be distributed efficiently and flexibly over time and space to accommodate different contexts. It is well established that selective attention enhances the corresponding neural responses, presumably implying that attention would persistently dwell on the task-relevant item. Meanwhile, recent studies, mostly in divided attentional contexts, suggest that attention does not remain stationary but samples objects alternately over time, suggesting a rhythmic view of attention. However, it remains unknown whether the dynamic mechanism essentially mediates attentional processes at a general level. Importantly, there is also a complete lack of direct neural evidence reflecting whether and how the brain rhythmically samples multiple visual objects during stimulus processing. To address these issues, in this study, we employed electroencephalography (EEG and a temporal response function (TRF approach, which can dissociate responses that exclusively represent a single object from the overall neuronal activity, to examine the spatiotemporal characteristics of attention in various attentional contexts. First, attention, which is characterized by inhibitory alpha-band (approximately 10 Hz activity in TRFs, switches between attended and unattended objects every approximately 200 ms, suggesting a sequential sampling even when attention is required to mostly stay on the attended object. Second, the attentional spatiotemporal pattern is modulated by the task context, such that alpha-mediated switching becomes increasingly prominent as the task requires a more uniform distribution of attention. Finally, the switching pattern correlates with attentional behavioral performance. Our work provides direct neural evidence supporting a generally central role of temporal organization mechanism in attention, such that multiple objects are sequentially sorted according to their priority in attentional contexts. The results suggest

  14. The Bacterial Sequential Markov Coalescent.

    Science.gov (United States)

    De Maio, Nicola; Wilson, Daniel J

    2017-05-01

    Bacteria can exchange and acquire new genetic material from other organisms directly and via the environment. This process, known as bacterial recombination, has a strong impact on the evolution of bacteria, for example, leading to the spread of antibiotic resistance across clades and species, and to the avoidance of clonal interference. Recombination hinders phylogenetic and transmission inference because it creates patterns of substitutions (homoplasies) inconsistent with the hypothesis of a single evolutionary tree. Bacterial recombination is typically modeled as statistically akin to gene conversion in eukaryotes, i.e. , using the coalescent with gene conversion (CGC). However, this model can be very computationally demanding as it needs to account for the correlations of evolutionary histories of even distant loci. So, with the increasing popularity of whole genome sequencing, the need has emerged for a faster approach to model and simulate bacterial genome evolution. We present a new model that approximates the coalescent with gene conversion: the bacterial sequential Markov coalescent (BSMC). Our approach is based on a similar idea to the sequential Markov coalescent (SMC)-an approximation of the coalescent with crossover recombination. However, bacterial recombination poses hurdles to a sequential Markov approximation, as it leads to strong correlations and linkage disequilibrium across very distant sites in the genome. Our BSMC overcomes these difficulties, and shows a considerable reduction in computational demand compared to the exact CGC, and very similar patterns in simulated data. We implemented our BSMC model within new simulation software FastSimBac. In addition to the decreased computational demand compared to previous bacterial genome evolution simulators, FastSimBac provides more general options for evolutionary scenarios, allowing population structure with migration, speciation, population size changes, and recombination hotspots. FastSimBac is

  15. Sequential analysis in neonatal research-systematic review.

    Science.gov (United States)

    Lava, Sebastiano A G; Elie, Valéry; Ha, Phuong Thi Viet; Jacqz-Aigrain, Evelyne

    2018-05-01

    As more new drugs are discovered, traditional designs come at their limits. Ten years after the adoption of the European Paediatric Regulation, we performed a systematic review on the US National Library of Medicine and Excerpta Medica database of sequential trials involving newborns. Out of 326 identified scientific reports, 21 trials were included. They enrolled 2832 patients, of whom 2099 were analyzed: the median number of neonates included per trial was 48 (IQR 22-87), median gestational age was 28.7 (IQR 27.9-30.9) weeks. Eighteen trials used sequential techniques to determine sample size, while 3 used continual reassessment methods for dose-finding. In 16 studies reporting sufficient data, the sequential design allowed to non-significantly reduce the number of enrolled neonates by a median of 24 (31%) patients (IQR - 4.75 to 136.5, p = 0.0674) with respect to a traditional trial. When the number of neonates finally included in the analysis was considered, the difference became significant: 35 (57%) patients (IQR 10 to 136.5, p = 0.0033). Sequential trial designs have not been frequently used in Neonatology. They might potentially be able to reduce the number of patients in drug trials, although this is not always the case. What is known: • In evaluating rare diseases in fragile populations, traditional designs come at their limits. About 20% of pediatric trials are discontinued, mainly because of recruitment problems. What is new: • Sequential trials involving newborns were infrequently used and only a few (n = 21) are available for analysis. • The sequential design allowed to non-significantly reduce the number of enrolled neonates by a median of 24 (31%) patients (IQR - 4.75 to 136.5, p = 0.0674).

  16. A Bayesian Theory of Sequential Causal Learning and Abstract Transfer.

    Science.gov (United States)

    Lu, Hongjing; Rojas, Randall R; Beckers, Tom; Yuille, Alan L

    2016-03-01

    Two key research issues in the field of causal learning are how people acquire causal knowledge when observing data that are presented sequentially, and the level of abstraction at which learning takes place. Does sequential causal learning solely involve the acquisition of specific cause-effect links, or do learners also acquire knowledge about abstract causal constraints? Recent empirical studies have revealed that experience with one set of causal cues can dramatically alter subsequent learning and performance with entirely different cues, suggesting that learning involves abstract transfer, and such transfer effects involve sequential presentation of distinct sets of causal cues. It has been demonstrated that pre-training (or even post-training) can modulate classic causal learning phenomena such as forward and backward blocking. To account for these effects, we propose a Bayesian theory of sequential causal learning. The theory assumes that humans are able to consider and use several alternative causal generative models, each instantiating a different causal integration rule. Model selection is used to decide which integration rule to use in a given learning environment in order to infer causal knowledge from sequential data. Detailed computer simulations demonstrate that humans rely on the abstract characteristics of outcome variables (e.g., binary vs. continuous) to select a causal integration rule, which in turn alters causal learning in a variety of blocking and overshadowing paradigms. When the nature of the outcome variable is ambiguous, humans select the model that yields the best fit with the recent environment, and then apply it to subsequent learning tasks. Based on sequential patterns of cue-outcome co-occurrence, the theory can account for a range of phenomena in sequential causal learning, including various blocking effects, primacy effects in some experimental conditions, and apparently abstract transfer of causal knowledge. Copyright © 2015

  17. A framework for sequential multiblock component methods

    NARCIS (Netherlands)

    Smilde, A.K.; Westerhuis, J.A.; Jong, S.de

    2003-01-01

    Multiblock or multiset methods are starting to be used in chemistry and biology to study complex data sets. In chemometrics, sequential multiblock methods are popular; that is, methods that calculate one component at a time and use deflation for finding the next component. In this paper a framework

  18. epSICAR: An Emerging Patterns based Approach to Sequential, Interleaved and Concurrent Activity Recognition

    DEFF Research Database (Denmark)

    Gu, Tao; Wu, Zhanqing; Tao, Xianping

    2009-01-01

    Recognizing human activity from sensor readings has recently attracted much research interest in pervasive computing. Human activity recognition is particularly challenging because activities are often performed in not only simple (i.e., sequential), but also complex (i.e., interleaved...

  19. Patterning pentacene surfaces by local oxidation nanolithography

    International Nuclear Information System (INIS)

    Losilla, N.S.; Martinez, J.; Bystrenova, E.; Greco, P.; Biscarini, F.; Garcia, R.

    2010-01-01

    Sequential and parallel local oxidation nanolithographies have been applied to pattern pentacene samples by creating a variety of nanostructures. The sequential local oxidation process is performed with an atomic force microscope and requires the application of a sequence of voltage pulses of 36 V for 1 ms. The parallel local oxidation process is performed by using a conductive and patterned stamp. Then, a voltage pulse is applied between the stamp and the pentacene surface. Patterns formed by arrays of parallel lines covering 1 mm 2 regions and with a periodicity of less than 1 μm have been generated in a few seconds. We also show that the patterns can be used as templates for the deposition of antibodies.

  20. Native Frames: Disentangling Sequential from Concerted Three-Body Fragmentation

    Science.gov (United States)

    Rajput, Jyoti; Severt, T.; Berry, Ben; Jochim, Bethany; Feizollah, Peyman; Kaderiya, Balram; Zohrabi, M.; Ablikim, U.; Ziaee, Farzaneh; Raju P., Kanaka; Rolles, D.; Rudenko, A.; Carnes, K. D.; Esry, B. D.; Ben-Itzhak, I.

    2018-03-01

    A key question concerning the three-body fragmentation of polyatomic molecules is the distinction of sequential and concerted mechanisms, i.e., the stepwise or simultaneous cleavage of bonds. Using laser-driven fragmentation of OCS into O++C++S+ and employing coincidence momentum imaging, we demonstrate a novel method that enables the clear separation of sequential and concerted breakup. The separation is accomplished by analyzing the three-body fragmentation in the native frame associated with each step and taking advantage of the rotation of the intermediate molecular fragment, CO2 + or CS2 + , before its unimolecular dissociation. This native-frame method works for any projectile (electrons, ions, or photons), provides details on each step of the sequential breakup, and enables the retrieval of the relevant spectra for sequential and concerted breakup separately. Specifically, this allows the determination of the branching ratio of all these processes in OCS3 + breakup. Moreover, we find that the first step of sequential breakup is tightly aligned along the laser polarization and identify the likely electronic states of the intermediate dication that undergo unimolecular dissociation in the second step. Finally, the separated concerted breakup spectra show clearly that the central carbon atom is preferentially ejected perpendicular to the laser field.

  1. Random sequential adsorption of cubes

    Science.gov (United States)

    Cieśla, Michał; Kubala, Piotr

    2018-01-01

    Random packings built of cubes are studied numerically using a random sequential adsorption algorithm. To compare the obtained results with previous reports, three different models of cube orientation sampling were used. Also, three different cube-cube intersection algorithms were tested to find the most efficient one. The study focuses on the mean saturated packing fraction as well as kinetics of packing growth. Microstructural properties of packings were analyzed using density autocorrelation function.

  2. The impact of eyewitness identifications from simultaneous and sequential lineups.

    Science.gov (United States)

    Wright, Daniel B

    2007-10-01

    Recent guidelines in the US allow either simultaneous or sequential lineups to be used for eyewitness identification. This paper investigates how potential jurors weight the probative value of the different outcomes from both of these types of lineups. Participants (n=340) were given a description of a case that included some exonerating and some incriminating evidence. There was either a simultaneous or a sequential lineup. Depending on the condition, an eyewitness chose the suspect, chose a filler, or made no identification. The participant had to judge the guilt of the suspect and decide whether to render a guilty verdict. For both simultaneous and sequential lineups an identification had a large effect,increasing the probability of a guilty verdict. There were no reliable effects detected between making no identification and identifying a filler. The effect sizes were similar for simultaneous and sequential lineups. These findings are important for judges and other legal professionals to know for trials involving lineup identifications.

  3. A Comparative Study of Frequent and Maximal Periodic Pattern Mining Algorithms in Spatiotemporal Databases

    Science.gov (United States)

    Obulesu, O.; Rama Mohan Reddy, A., Dr; Mahendra, M.

    2017-08-01

    Detecting regular and efficient cyclic models is the demanding activity for data analysts due to unstructured, vigorous and enormous raw information produced from web. Many existing approaches generate large candidate patterns in the occurrence of huge and complex databases. In this work, two novel algorithms are proposed and a comparative examination is performed by considering scalability and performance parameters. The first algorithm is, EFPMA (Extended Regular Model Detection Algorithm) used to find frequent sequential patterns from the spatiotemporal dataset and the second one is, ETMA (Enhanced Tree-based Mining Algorithm) for detecting effective cyclic models with symbolic database representation. EFPMA is an algorithm grows models from both ends (prefixes and suffixes) of detected patterns, which results in faster pattern growth because of less levels of database projection compared to existing approaches such as Prefixspan and SPADE. ETMA uses distinct notions to store and manage transactions data horizontally such as segment, sequence and individual symbols. ETMA exploits a partition-and-conquer method to find maximal patterns by using symbolic notations. Using this algorithm, we can mine cyclic models in full-series sequential patterns including subsection series also. ETMA reduces the memory consumption and makes use of the efficient symbolic operation. Furthermore, ETMA only records time-series instances dynamically, in terms of character, series and section approaches respectively. The extent of the pattern and proving efficiency of the reducing and retrieval techniques from synthetic and actual datasets is a really open & challenging mining problem. These techniques are useful in data streams, traffic risk analysis, medical diagnosis, DNA sequence Mining, Earthquake prediction applications. Extensive investigational outcomes illustrates that the algorithms outperforms well towards efficiency and scalability than ECLAT, STNR and MAFIA approaches.

  4. An accurate approximate solution of optimal sequential age replacement policy for a finite-time horizon

    International Nuclear Information System (INIS)

    Jiang, R.

    2009-01-01

    It is difficult to find the optimal solution of the sequential age replacement policy for a finite-time horizon. This paper presents an accurate approximation to find an approximate optimal solution of the sequential replacement policy. The proposed approximation is computationally simple and suitable for any failure distribution. Their accuracy is illustrated by two examples. Based on the approximate solution, an approximate estimate for the total cost is derived.

  5. Systems-level modeling the effects of arsenic exposure with sequential pulsed and fluctuating patterns for tilapia and freshwater clam

    International Nuclear Information System (INIS)

    Chen, W.-Y.; Tsai, J.-W.; Ju, Y.-R.; Liao, C.-M.

    2010-01-01

    The purpose of this paper was to use quantitative systems-level approach employing biotic ligand model based threshold damage model to examine physiological responses of tilapia and freshwater clam to sequential pulsed and fluctuating arsenic concentrations. We tested present model and triggering mechanisms by carrying out a series of modeling experiments where we used periodic pulses and sine-wave as featured exposures. Our results indicate that changes in the dominant frequencies and pulse timing can shift the safe rate distributions for tilapia, but not for that of freshwater clam. We found that tilapia increase bioenergetic costs to maintain the acclimation during pulsed and sine-wave exposures. Our ability to predict the consequences of physiological variation under time-varying exposure patterns has also implications for optimizing species growing, cultivation strategies, and risk assessment in realistic situations. - Systems-level modeling the pulsed and fluctuating arsenic exposures.

  6. Systems-level modeling the effects of arsenic exposure with sequential pulsed and fluctuating patterns for tilapia and freshwater clam

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.-Y. [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Tsai, J.-W. [Institute of Ecology and Evolutionary Ecology, China Medical University, Taichung 40402, Taiwan (China); Ju, Y.-R. [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Liao, C.-M., E-mail: cmliao@ntu.edu.t [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2010-05-15

    The purpose of this paper was to use quantitative systems-level approach employing biotic ligand model based threshold damage model to examine physiological responses of tilapia and freshwater clam to sequential pulsed and fluctuating arsenic concentrations. We tested present model and triggering mechanisms by carrying out a series of modeling experiments where we used periodic pulses and sine-wave as featured exposures. Our results indicate that changes in the dominant frequencies and pulse timing can shift the safe rate distributions for tilapia, but not for that of freshwater clam. We found that tilapia increase bioenergetic costs to maintain the acclimation during pulsed and sine-wave exposures. Our ability to predict the consequences of physiological variation under time-varying exposure patterns has also implications for optimizing species growing, cultivation strategies, and risk assessment in realistic situations. - Systems-level modeling the pulsed and fluctuating arsenic exposures.

  7. Biaxially mechanical tuning of 2-D reversible and irreversible surface topologies through simultaneous and sequential wrinkling.

    Science.gov (United States)

    Yin, Jie; Yagüe, Jose Luis; Boyce, Mary C; Gleason, Karen K

    2014-02-26

    Controlled buckling is a facile means of structuring surfaces. The resulting ordered wrinkling topologies provide surface properties and features desired for multifunctional applications. Here, we study the biaxially dynamic tuning of two-dimensional wrinkled micropatterns under cyclic mechanical stretching/releasing/restretching simultaneously or sequentially. A biaxially prestretched PDMS substrate is coated with a stiff polymer deposited by initiated chemical vapor deposition (iCVD). Applying a mechanical release/restretch cycle in two directions loaded simultaneously or sequentially to the wrinkled system results in a variety of dynamic and tunable wrinkled geometries, the evolution of which is investigated using in situ optical profilometry, numerical simulations, and theoretical modeling. Results show that restretching ordered herringbone micropatterns, created through sequential release of biaxial prestrain, leads to reversible and repeatable surface topography. The initial flat surface and the same wrinkled herringbone pattern are obtained alternatively after cyclic release/restretch processes, owing to the highly ordered structure leaving no avenue for trapping irregular topological regions during cycling as further evidenced by the uniformity of strains distributions and negligible residual strain. Conversely, restretching disordered labyrinth micropatterns created through simultaneous release shows an irreversible surface topology whether after sequential or simultaneous restretching due to creation of irregular surface topologies with regions of highly concentrated strain upon formation of the labyrinth which then lead to residual strains and trapped topologies upon cycling; furthermore, these trapped topologies depend upon the subsequent strain histories as well as the cycle. The disordered labyrinth pattern varies after each cyclic release/restretch process, presenting residual shallow patterns instead of achieving a flat state. The ability to

  8. Double-blind photo lineups using actual eyewitnesses: an experimental test of a sequential versus simultaneous lineup procedure.

    Science.gov (United States)

    Wells, Gary L; Steblay, Nancy K; Dysart, Jennifer E

    2015-02-01

    Eyewitnesses (494) to actual crimes in 4 police jurisdictions were randomly assigned to view simultaneous or sequential photo lineups using laptop computers and double-blind administration. The sequential procedure used in the field experiment mimicked how it is conducted in actual practice (e.g., using a continuation rule, witness does not know how many photos are to be viewed, witnesses resolve any multiple identifications), which is not how most lab experiments have tested the sequential lineup. No significant differences emerged in rates of identifying lineup suspects (25% overall) but the sequential procedure produced a significantly lower rate (11%) of identifying known-innocent lineup fillers than did the simultaneous procedure (18%). The simultaneous/sequential pattern did not significantly interact with estimator variables and no lineup-position effects were observed for either the simultaneous or sequential procedures. Rates of nonidentification were not significantly different for simultaneous and sequential but nonidentifiers from the sequential procedure were more likely to use the "not sure" response option than were nonidentifiers from the simultaneous procedure. Among witnesses who made an identification, 36% (41% of simultaneous and 32% of sequential) identified a known-innocent filler rather than a suspect, indicating that eyewitness performance overall was very poor. The results suggest that the sequential procedure that is used in the field reduces the identification of known-innocent fillers, but the differences are relatively small.

  9. Effects of musical training on sound pattern processing in high-school students.

    Science.gov (United States)

    Wang, Wenjung; Staffaroni, Laura; Reid, Errold; Steinschneider, Mitchell; Sussman, Elyse

    2009-05-01

    Recognizing melody in music involves detection of both the pitch intervals and the silence between sequentially presented sounds. This study tested the hypothesis that active musical training in adolescents facilitates the ability to passively detect sequential sound patterns compared to musically non-trained age-matched peers. Twenty adolescents, aged 15-18 years, were divided into groups according to their musical training and current experience. A fixed order tone pattern was presented at various stimulus rates while electroencephalogram was recorded. The influence of musical training on passive auditory processing of the sound patterns was assessed using components of event-related brain potentials (ERPs). The mismatch negativity (MMN) ERP component was elicited in different stimulus onset asynchrony (SOA) conditions in non-musicians than musicians, indicating that musically active adolescents were able to detect sound patterns across longer time intervals than age-matched peers. Musical training facilitates detection of auditory patterns, allowing the ability to automatically recognize sequential sound patterns over longer time periods than non-musical counterparts.

  10. Modelling sequentially scored item responses

    NARCIS (Netherlands)

    Akkermans, W.

    2000-01-01

    The sequential model can be used to describe the variable resulting from a sequential scoring process. In this paper two more item response models are investigated with respect to their suitability for sequential scoring: the partial credit model and the graded response model. The investigation is

  11. Sequential and Simultaneous Processing in Children with Learning Disabilities: An Attempted Replication.

    Science.gov (United States)

    Bain, Sherry K.

    1993-01-01

    Analysis of Kaufman Assessment Battery for Children (K-ABC) Sequential and Simultaneous Processing scores of 94 children (ages 6-12) with learning disabilities produced factor patterns generally supportive of the traditional K-ABC Mental Processing structure with the exception of Spatial Memory. The sample exhibited relative processing strengths…

  12. A Sequential Analysis of Parent-Child Interactions in Anxious and Nonanxious Families

    Science.gov (United States)

    Williams, Sarah R.; Kertz, Sarah J.; Schrock, Matthew D.; Woodruff-Borden, Janet

    2012-01-01

    Although theoretical work has suggested that reciprocal behavior patterns between parent and child may be important in the development of childhood anxiety, most empirical work has failed to consider the bidirectional nature of interactions. The current study sought to address this limitation by utilizing a sequential approach to exploring…

  13. Multi-agent sequential hypothesis testing

    KAUST Repository

    Kim, Kwang-Ki K.

    2014-12-15

    This paper considers multi-agent sequential hypothesis testing and presents a framework for strategic learning in sequential games with explicit consideration of both temporal and spatial coordination. The associated Bayes risk functions explicitly incorporate costs of taking private/public measurements, costs of time-difference and disagreement in actions of agents, and costs of false declaration/choices in the sequential hypothesis testing. The corresponding sequential decision processes have well-defined value functions with respect to (a) the belief states for the case of conditional independent private noisy measurements that are also assumed to be independent identically distributed over time, and (b) the information states for the case of correlated private noisy measurements. A sequential investment game of strategic coordination and delay is also discussed as an application of the proposed strategic learning rules.

  14. Sequential charged particle reaction

    International Nuclear Information System (INIS)

    Hori, Jun-ichi; Ochiai, Kentaro; Sato, Satoshi; Yamauchi, Michinori; Nishitani, Takeo

    2004-01-01

    The effective cross sections for producing the sequential reaction products in F82H, pure vanadium and LiF with respect to the 14.9-MeV neutron were obtained and compared with the estimation ones. Since the sequential reactions depend on the secondary charged particles behavior, the effective cross sections are corresponding to the target nuclei and the material composition. The effective cross sections were also estimated by using the EAF-libraries and compared with the experimental ones. There were large discrepancies between estimated and experimental values. Additionally, we showed the contribution of the sequential reaction on the induced activity and dose rate in the boundary region with water. From the present study, it has been clarified that the sequential reactions are of great importance to evaluate the dose rates around the surface of cooling pipe and the activated corrosion products. (author)

  15. Prosody and alignment: a sequential perspective

    Science.gov (United States)

    Szczepek Reed, Beatrice

    2010-12-01

    In their analysis of a corpus of classroom interactions in an inner city high school, Roth and Tobin describe how teachers and students accomplish interactional alignment by prosodically matching each other's turns. Prosodic matching, and specific prosodic patterns are interpreted as signs of, and contributions to successful interactional outcomes and positive emotions. Lack of prosodic matching, and other specific prosodic patterns are interpreted as features of unsuccessful interactions, and negative emotions. This forum focuses on the article's analysis of the relation between interpersonal alignment, emotion and prosody. It argues that prosodic matching, and other prosodic linking practices, play a primarily sequential role, i.e. one that displays the way in which participants place and design their turns in relation to other participants' turns. Prosodic matching, rather than being a conversational action in itself, is argued to be an interactional practice (Schegloff 1997), which is not always employed for the accomplishment of `positive', or aligning actions.

  16. An experimental study of exogenous lipoid pneumonia : sequential changes in high-resolution CT and MR findings

    International Nuclear Information System (INIS)

    Kim, Kyeong Ah; Kang, Eun Young; Kim, Dae Hyun; Park, Sang Woo; Choi, Jeong Cheol; Kim, Ae Ree; Kim, Han Kyum; Cha, In Ho

    1999-01-01

    To evaluate sequential changes in high-resolution CT(HRCT) and MR findings of exogenous lipoid pneumonia in rabbits and to compare the radiologic and histopathologic findings. A single endobronchial administration of shark liver oil(0.5 or 1 ml/kg of body weight) was given to 25 rabbits. HRCT scans were obtained immediately(n=17), at 1 day(n=14), 3 days(n=10), 1 week(n=15), 2 weeks(n=10), 4 weeks(n=9), 6 weeks(n=5), 8 weeks(n=6), 10 weeks(n=4), 12 weeks(n=2), 14 weeks(n=3), and 16 weeks(n=2) after administration. Changes in distribution, extent, and attenuation were assessed on HRCT scans. MR scans were obtained immediately(n=12), at 1 day(n=9), 3 days(n=9), 1 week(n=15), 2 weeks(n=9), 4 weeks(n=11), 6 weeks(n=5), 8 weeks(n=7), 10 weeks(n=3), 14 weeks(n=3), and at 16 weeks(n=2) after administration. Changes in distribution, extent, and signal intensity were assessed on MR scans. In 16 rabbits, CT and MR findings were compared with histopatholo-gic findings obtained in the same plane. HRCT findings included consolidation with air-bronchogram, ground-glass attenuation and fat attenuation within the lesion at earlier stages(immediate-2 weeks). The extent of lesions was greatest at 1 week, and was then seen to gradually decrease on follow-up CT scans. T1-weighted MR images(T1WI) showed high or intermediate signal intensity(SI) at earlier stages and intermediate SI at later stages, while T2-weighted MR images(T2WI) showed high SI at both earlier and later stages. Histopathologic correlation showed that ground-glass attenuation and consolidation on HRCT reflected intraalveolar lipid-laden macrophages, cuboidal metaplasia of alveolar epithelial cells, and alveolar septal widening with inflammatory cell infiltration. Maximal infiltration of oil in the lung correlated closely with the peak low-attenuation seen on CT scans and the high signal intensity seen on T1WI. Shark liver oil-induced exogenous lipoid pneumonia in rabbits is reliably diagnosed by HRCT and MR during

  17. Motif trie: An efficient text index for pattern discovery with don't cares

    DEFF Research Database (Denmark)

    Grossi, Roberto; Menconi, Giulia; Pisanti, Nadia

    2017-01-01

    We introduce the motif trie data structure, which has applications in pattern matching and discovery in genomic analysis, plagiarism detection, data mining, intrusion detection, spam fighting and time series analysis, to name a few. Here the extraction of recurring patterns in sequential and text......We introduce the motif trie data structure, which has applications in pattern matching and discovery in genomic analysis, plagiarism detection, data mining, intrusion detection, spam fighting and time series analysis, to name a few. Here the extraction of recurring patterns in sequential...

  18. Optimal Energy Management of Multi-Microgrids with Sequentially Coordinated Operations

    Directory of Open Access Journals (Sweden)

    Nah-Oak Song

    2015-08-01

    Full Text Available We propose an optimal electric energy management of a cooperative multi-microgrid community with sequentially coordinated operations. The sequentially coordinated operations are suggested to distribute computational burden and yet to make the optimal 24 energy management of multi-microgrids possible. The sequential operations are mathematically modeled to find the optimal operation conditions and illustrated with physical interpretation of how to achieve optimal energy management in the cooperative multi-microgrid community. This global electric energy optimization of the cooperative community is realized by the ancillary internal trading between the microgrids in the cooperative community which reduces the extra cost from unnecessary external trading by adjusting the electric energy production amounts of combined heat and power (CHP generators and amounts of both internal and external electric energy trading of the cooperative community. A simulation study is also conducted to validate the proposed mathematical energy management models.

  19. Simultaneous Versus Sequential Complementarity in the Adoption of Technological and Organizational Innovations

    DEFF Research Database (Denmark)

    Battisti, Giuliana; Rabbiosi, Larissa; Colombo, Massimo G.

    2015-01-01

    It is generally suggested that technological and organizational innovations, being complementary, need to be adopted simultaneously. Nevertheless, sequential rather than simultaneous adoption of these two types of innovation may be optimal. In this paper, we analyze the pattern of mutual causation...... of technological and organizational innovations and contribute to the understanding of their interdependencies......

  20. Transfer printing of 3D hierarchical gold structures using a sequentially imprinted polymer stamp

    International Nuclear Information System (INIS)

    Zhang Fengxiang; Low, Hong Yee

    2008-01-01

    Complex three-dimensional (3D) hierarchical structures on polymeric materials are fabricated through a process referred to as sequential imprinting. In this work, the sequentially imprinted polystyrene film is used as a soft stamp to replicate hierarchical structures onto gold (Au) films, and the Au structures are then transferred to a substrate by transfer printing at an elevated temperature and pressure. Continuous and isolated 3D structures can be selectively fabricated with the assistance of thermo-mechanical deformation of the polymer stamp. Hierarchical Au structures are achieved without the need for a corresponding three-dimensionally patterned mold

  1. How ants find each other; temporal and spatial patterns in nuptial flights

    NARCIS (Netherlands)

    Noordijk, J.; Morssinkhof, R.; Boer, P.; Schaffers, A.P.; Heijerman, Th.; Sykora, K.V.

    2008-01-01

    Reproduction is a key factor in understanding population ecology and therefore species occurrence. However, patterns in reproductive behaviour for distinct ant species remain insufficiently known. In this paper strategies in mate finding are studied for six ant species (Lasius niger, Lasius

  2. Sequentially-crosslinked bioactive hydrogels as nano-patterned substrates with customizable stiffness and degradation for corneal tissue engineering applications.

    Science.gov (United States)

    Rizwan, Muhammad; Peh, Gary S L; Ang, Heng-Pei; Lwin, Nyein Chan; Adnan, Khadijah; Mehta, Jodhbir S; Tan, Wui Siew; Yim, Evelyn K F

    2017-03-01

    Naturally-bioactive hydrogels like gelatin provide favorable properties for tissue-engineering but lack sufficient mechanical strength for use as implantable tissue engineering substrates. Complex fabrication or multi-component additives can improve material strength, but often compromises other properties. Studies have shown gelatin methacrylate (GelMA) as a bioactive hydrogel with diverse tissue growth applications. We hypothesize that, with suitable material modifications, GelMA could be employed for growth and implantation of tissue-engineered human corneal endothelial cell (HCEC) monolayer. Tissue-engineered HCEC monolayer could potentially be used to treat corneal blindness due to corneal endothelium dysfunction. Here, we exploited a sequential hybrid (physical followed by UV) crosslinking to create an improved material, named as GelMA+, with over 8-fold increase in mechanical strength as compared to regular GelMA. The presence of physical associations increased the subsequent UV-crosslinking efficiency resulting in robust materials able to withstand standard endothelium insertion surgical device loading. Favorable biodegradation kinetics were also measured in vitro and in vivo. We achieved hydrogels patterning with nano-scale resolution by use of oxygen impermeable stamps that overcome the limitations of PDMS based molding processes. Primary HCEC monolayers grown on GelMA+ carrier patterned with pillars of optimal dimension demonstrated improved zona-occludin-1 expression, higher cell density and cell size homogeneity, which are indications of functionally-superior transplantable monolayers. The hybrid crosslinking and fabrication approach offers potential utility for development of implantable tissue-engineered cell-carrier constructs with enhanced bio-functional properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Variation among heritage speakers: Sequential vs. simultaneous bilinguals

    Directory of Open Access Journals (Sweden)

    Teresa Lee

    2013-08-01

    Full Text Available This study examines the differences in the grammatical knowledge of two types of heritage speakers of Korean. Early simultaneous bilinguals are exposed to both English and the heritage language from birth, whereas early sequential bilinguals are exposed to the heritage language first and then to English upon schooling. A listening comprehension task involving relative clauses was conducted with 51 beginning-level Korean heritage speakers. The results showed that the early sequential bilinguals exhibited much more accurate knowledge than the early simultaneous bilinguals, who lacked rudimentary knowledge of Korean relative clauses. Drawing on the findings of adult and child Korean L1 data on the acquisition of relative clauses, the performance of each group is discussed with respect to attrition and incomplete acquisition of the heritage language.

  4. Colonic uptake patterns of F-18-FDG PET in asymptomatic adults: comparison with colonoscopic findings

    International Nuclear Information System (INIS)

    Pai, Moon Sun; Cho, Yoo Kyung; Jung, Sung Ae; Shim, Ki Nam; Lee, Hong Soo

    2005-01-01

    Physiologic intestinal FDG uptake is frequently observed in asymptomatic individuals for cancer screening FDG PET. Colonic FDG accumulation is a well-known confusing findings that interfere true cancer detection or cause false positive. The aim of this study was to evaluate the pattern and intensity of colonic uptake in whole body FDG PET in asymptomatic healthy adults and to correlate them with colonoscopic findings. We reviewed retrospectively 64 subjects (age: 27-87, M:F=31:33) who underwent both FDG PET and colonoscopy for cancer screening. FDG uptake patterns were classified as focal, segmental and diffuse. Maximum SUV were measured. The PET results were compared with colonoscopic and histologic findings. In 13 patients FDG bowel uptake was interpreted as focal, in 17 patients as segmental and in 34 patients as diffuse uptake. Six adenomas (17.6%, average diameter=5.0 mm) were found in diffuse pattern, 7 adenomas (41.1%, 5.6 mm) in segmental and 4 adenomas and 1 adenocarcinoma (38.5%, 16.4 mm) in focal uptake pattern. In patients with focal uptake, four were non-adenomatous pathologic lesions (30.8%, 2 intestinal tuberculosis, 2 mucosal ulcer). There is no difference of mean SUV between patients with adenoma and with negative colonoscopic results in each group of intestinal FDG pattern (Diffuse: 1.7 ± 0.1 vs 1.9 ± 0.5, Segmental: 4.8 ± 3.6 vs 4.2 ± 1.2, Focal: 6.5 ± 4.7 vs 3.5 ± 1.3). Large adenomas (>1 cm) can be detected more in the focal uptake pattern (4 out of 5) rather than in segmental (1 out of 7) or diffuse uptake (none) and had higher SUV (6.3 ± 4.8) than small adenomas (3.5 ± 3.0)(statistically insignificant). Focal FDG uptake is associated more often with large adenoma and other pathologic findings in colonoscopy. Segmental uptake cannot discriminate presence of adenoma from negative results, while diffuse pattern may have more chance to be normal

  5. Adaptive decision making in a dynamic environment: a test of a sequential sampling model of relative judgment.

    Science.gov (United States)

    Vuckovic, Anita; Kwantes, Peter J; Neal, Andrew

    2013-09-01

    Research has identified a wide range of factors that influence performance in relative judgment tasks. However, the findings from this research have been inconsistent. Studies have varied with respect to the identification of causal variables and the perceptual and decision-making mechanisms underlying performance. Drawing on the ecological rationality approach, we present a theory of the judgment and decision-making processes involved in a relative judgment task that explains how people judge a stimulus and adapt their decision process to accommodate their own uncertainty associated with those judgments. Undergraduate participants performed a simulated air traffic control conflict detection task. Across two experiments, we systematically manipulated variables known to affect performance. In the first experiment, we manipulated the relative distances of aircraft to a common destination while holding aircraft speeds constant. In a follow-up experiment, we introduced a direct manipulation of relative speed. We then fit a sequential sampling model to the data, and used the best fitting parameters to infer the decision-making processes responsible for performance. Findings were consistent with the theory that people adapt to their own uncertainty by adjusting their criterion and the amount of time they take to collect evidence in order to make a more accurate decision. From a practical perspective, the paper demonstrates that one can use a sequential sampling model to understand performance in a dynamic environment, allowing one to make sense of and interpret complex patterns of empirical findings that would otherwise be difficult to interpret using standard statistical analyses. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  6. Remarks on sequential designs in risk assessment

    International Nuclear Information System (INIS)

    Seidenfeld, T.

    1982-01-01

    The special merits of sequential designs are reviewed in light of particular challenges that attend risk assessment for human population. The kinds of ''statistical inference'' are distinguished and the problem of design which is pursued is the clash between Neyman-Pearson and Bayesian programs of sequential design. The value of sequential designs is discussed and the Neyman-Pearson vs. Bayesian sequential designs are probed in particular. Finally, warnings with sequential designs are considered, especially in relation to utilitarianism

  7. Learning new sequential stepping patterns requires striatal plasticity during the earliest phase of acquisition.

    Science.gov (United States)

    Nakamura, Toru; Nagata, Masatoshi; Yagi, Takeshi; Graybiel, Ann M; Yamamori, Tetsuo; Kitsukawa, Takashi

    2017-04-01

    Animals including humans execute motor behavior to reach their goals. For this purpose, they must choose correct strategies according to environmental conditions and shape many parameters of their movements, including their serial order and timing. To investigate the neurobiology underlying such skills, we used a multi-sensor equipped, motor-driven running wheel with adjustable sequences of foothold pegs on which mice ran to obtain water reward. When the peg patterns changed from a familiar pattern to a new pattern, the mice had to learn and implement new locomotor strategies in order to receive reward. We found that the accuracy of stepping and the achievement of water reward improved with the new learning after changes in the peg-pattern, and c-Fos expression levels assayed after the first post-switch session were high in both dorsolateral striatum and motor cortex, relative to post-switch plateau levels. Combined in situ hybridization and immunohistochemistry of striatal sections demonstrated that both enkephalin-positive (indirect pathway) neurons and substance P-positive (direct pathway) neurons were recruited specifically after the pattern switches, as were interneurons expressing neuronal nitric oxide synthase. When we blocked N-methyl-D-aspartate (NMDA) receptors in the dorsolateral striatum by injecting the NMDA receptor antagonist, D-2-amino-5-phosphonopentanoic acid (AP5), we found delays in early post-switch improvement in performance. These findings suggest that the dorsolateral striatum is activated on detecting shifts in environment to adapt motor behavior to the new context via NMDA-dependent plasticity, and that this plasticity may underlie forming and breaking skills and habits as well as to behavioral difficulties in clinical disorders. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  8. Ordered alternating binary polymer nanodroplet array by sequential spin dewetting.

    Science.gov (United States)

    Bhandaru, Nandini; Das, Anuja; Salunke, Namrata; Mukherjee, Rabibrata

    2014-12-10

    We report a facile technique for fabricating an ordered array of nearly equal-sized mesoscale polymer droplets of two constituent polymers (polystyrene, PS and poly(methyl methacrylate), PMMA) arranged in an alternating manner on a topographically patterned substrate. The self-organized array of binary polymers is realized by sequential spin dewetting. First, a dilute solution of PMMA is spin-dewetted on a patterned substrate, resulting in an array of isolated PMMA droplets arranged along the substrate grooves due to self-organization during spin coating itself. The sample is then silanized with octadecyltrichlorosilane (OTS), and subsequently, a dilute solution of PS is spin-coated on to it, which also undergoes spin dewetting. The spin-dewetted PS drops having a size nearly equal to the pre-existing PMMA droplets position themselves between two adjacent PMMA drops under appropriate conditions, forming an alternating binary polymer droplet array. The alternating array formation takes place for a narrow range of solution concentration for both the polymers and depends on the geometry of the substrate. The size of the droplets depends on the extent of confinement, and droplets as small as 100 nm can be obtained by this method, on a suitable template. The findings open up the possibility of creating novel surfaces having ordered multimaterial domains with a potential multifunctional capability.

  9. Sequential lineup laps and eyewitness accuracy.

    Science.gov (United States)

    Steblay, Nancy K; Dietrich, Hannah L; Ryan, Shannon L; Raczynski, Jeanette L; James, Kali A

    2011-08-01

    Police practice of double-blind sequential lineups prompts a question about the efficacy of repeated viewings (laps) of the sequential lineup. Two laboratory experiments confirmed the presence of a sequential lap effect: an increase in witness lineup picks from first to second lap, when the culprit was a stranger. The second lap produced more errors than correct identifications. In Experiment 2, lineup diagnosticity was significantly higher for sequential lineup procedures that employed a single versus double laps. Witnesses who elected to view a second lap made significantly more errors than witnesses who chose to stop after one lap or those who were required to view two laps. Witnesses with prior exposure to the culprit did not exhibit a sequential lap effect.

  10. Decision-making in research tasks with sequential testing.

    Directory of Open Access Journals (Sweden)

    Thomas Pfeiffer

    Full Text Available BACKGROUND: In a recent controversial essay, published by JPA Ioannidis in PLoS Medicine, it has been argued that in some research fields, most of the published findings are false. Based on theoretical reasoning it can be shown that small effect sizes, error-prone tests, low priors of the tested hypotheses and biases in the evaluation and publication of research findings increase the fraction of false positives. These findings raise concerns about the reliability of research. However, they are based on a very simple scenario of scientific research, where single tests are used to evaluate independent hypotheses. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we present computer simulations and experimental approaches for analyzing more realistic scenarios. In these scenarios, research tasks are solved sequentially, i.e. subsequent tests can be chosen depending on previous results. We investigate simple sequential testing and scenarios where only a selected subset of results can be published and used for future rounds of test choice. Results from computer simulations indicate that for the tasks analyzed in this study, the fraction of false among the positive findings declines over several rounds of testing if the most informative tests are performed. Our experiments show that human subjects frequently perform the most informative tests, leading to a decline of false positives as expected from the simulations. CONCLUSIONS/SIGNIFICANCE: For the research tasks studied here, findings tend to become more reliable over time. We also find that the performance in those experimental settings where not all performed tests could be published turned out to be surprisingly inefficient. Our results may help optimize existing procedures used in the practice of scientific research and provide guidance for the development of novel forms of scholarly communication.

  11. Robustness of the Sequential Lineup Advantage

    Science.gov (United States)

    Gronlund, Scott D.; Carlson, Curt A.; Dailey, Sarah B.; Goodsell, Charles A.

    2009-01-01

    A growing movement in the United States and around the world involves promoting the advantages of conducting an eyewitness lineup in a sequential manner. We conducted a large study (N = 2,529) that included 24 comparisons of sequential versus simultaneous lineups. A liberal statistical criterion revealed only 2 significant sequential lineup…

  12. Efficient sequential and parallel algorithms for record linkage.

    Science.gov (United States)

    Mamun, Abdullah-Al; Mi, Tian; Aseltine, Robert; Rajasekaran, Sanguthevar

    2014-01-01

    Integrating data from multiple sources is a crucial and challenging problem. Even though there exist numerous algorithms for record linkage or deduplication, they suffer from either large time needs or restrictions on the number of datasets that they can integrate. In this paper we report efficient sequential and parallel algorithms for record linkage which handle any number of datasets and outperform previous algorithms. Our algorithms employ hierarchical clustering algorithms as the basis. A key idea that we use is radix sorting on certain attributes to eliminate identical records before any further processing. Another novel idea is to form a graph that links similar records and find the connected components. Our sequential and parallel algorithms have been tested on a real dataset of 1,083,878 records and synthetic datasets ranging in size from 50,000 to 9,000,000 records. Our sequential algorithm runs at least two times faster, for any dataset, than the previous best-known algorithm, the two-phase algorithm using faster computation of the edit distance (TPA (FCED)). The speedups obtained by our parallel algorithm are almost linear. For example, we get a speedup of 7.5 with 8 cores (residing in a single node), 14.1 with 16 cores (residing in two nodes), and 26.4 with 32 cores (residing in four nodes). We have compared the performance of our sequential algorithm with TPA (FCED) and found that our algorithm outperforms the previous one. The accuracy is the same as that of this previous best-known algorithm.

  13. Embedding responses in spontaneous neural activity shaped through sequential learning.

    Directory of Open Access Journals (Sweden)

    Tomoki Kurikawa

    Full Text Available Recent experimental measurements have demonstrated that spontaneous neural activity in the absence of explicit external stimuli has remarkable spatiotemporal structure. This spontaneous activity has also been shown to play a key role in the response to external stimuli. To better understand this role, we proposed a viewpoint, "memories-as-bifurcations," that differs from the traditional "memories-as-attractors" viewpoint. Memory recall from the memories-as-bifurcations viewpoint occurs when the spontaneous neural activity is changed to an appropriate output activity upon application of an input, known as a bifurcation in dynamical systems theory, wherein the input modifies the flow structure of the neural dynamics. Learning, then, is a process that helps create neural dynamical systems such that a target output pattern is generated as an attractor upon a given input. Based on this novel viewpoint, we introduce in this paper an associative memory model with a sequential learning process. Using a simple hebbian-type learning, the model is able to memorize a large number of input/output mappings. The neural dynamics shaped through the learning exhibit different bifurcations to make the requested targets stable upon an increase in the input, and the neural activity in the absence of input shows chaotic dynamics with occasional approaches to the memorized target patterns. These results suggest that these dynamics facilitate the bifurcations to each target attractor upon application of the corresponding input, which thus increases the capacity for learning. This theoretical finding about the behavior of the spontaneous neural activity is consistent with recent experimental observations in which the neural activity without stimuli wanders among patterns evoked by previously applied signals. In addition, the neural networks shaped by learning properly reflect the correlations of input and target-output patterns in a similar manner to those designed in

  14. Multi-agent sequential hypothesis testing

    KAUST Repository

    Kim, Kwang-Ki K.; Shamma, Jeff S.

    2014-01-01

    incorporate costs of taking private/public measurements, costs of time-difference and disagreement in actions of agents, and costs of false declaration/choices in the sequential hypothesis testing. The corresponding sequential decision processes have well

  15. Considering User's Access Pattern in Multimedia File Systems

    Science.gov (United States)

    Cho, KyoungWoon; Ryu, YeonSeung; Won, Youjip; Koh, Kern

    2002-12-01

    Legacy buffer cache management schemes for multimedia server are grounded at the assumption that the application sequentially accesses the multimedia file. However, user access pattern may not be sequential in some circumstances, for example, in distance learning application, where the user may exploit the VCR-like function(rewind and play) of the system and accesses the particular segments of video repeatedly in the middle of sequential playback. Such a looping reference can cause a significant performance degradation of interval-based caching algorithms. And thus an appropriate buffer cache management scheme is required in order to deliver desirable performance even under the workload that exhibits looping reference behavior. We propose Adaptive Buffer cache Management(ABM) scheme which intelligently adapts to the file access characteristics. For each opened file, ABM applies either the LRU replacement or the interval-based caching depending on the Looping Reference Indicator, which indicates that how strong temporally localized access pattern is. According to our experiment, ABM exhibits better buffer cache miss ratio than interval-based caching or LRU, especially when the workload exhibits not only sequential but also looping reference property.

  16. Double-label autoradiographic deoxyglucose method for sequential measurement of regional cerebral glucose utilization

    Energy Technology Data Exchange (ETDEWEB)

    Redies, C; Diksic, M; Evans, A C; Gjedde, A; Yamamoto, Y L

    1987-08-01

    A new double-label autoradiographic glucose analog method for the sequential measurement of altered regional cerebral metabolic rates for glucose in the same animal is presented. This method is based on the sequential injection of two boluses of glucose tracer labeled with two different isotopes (short-lived /sup 18/F and long-lived /sup 3/H, respectively). An operational equation is derived which allows the determination of glucose utilization for the time period before the injection of the second tracer; this equation corrects for accumulation and loss of the first tracer from the metabolic pool occurring after the injection of the second tracer. An error analysis of this operational equation is performed. The double-label deoxyglucose method is validated in the primary somatosensory (''barrel'') cortex of the anesthetized rat. Two different rows of whiskers were stimulated sequentially in each rat; the two periods of stimulation were each preceded by an injection of glucose tracer. After decapitation, dried brain slices were first exposed, in direct contact, to standard X-ray film and then to uncoated, ''tritium-sensitive'' film. Results show that the double-label deoxyglucose method proposed in this paper allows the quantification and complete separation of glucose utilization patterns elicited by two different stimulations sequentially applied in the same animal.

  17. Sequential stochastic optimization

    CERN Document Server

    Cairoli, Renzo

    1996-01-01

    Sequential Stochastic Optimization provides mathematicians and applied researchers with a well-developed framework in which stochastic optimization problems can be formulated and solved. Offering much material that is either new or has never before appeared in book form, it lucidly presents a unified theory of optimal stopping and optimal sequential control of stochastic processes. This book has been carefully organized so that little prior knowledge of the subject is assumed; its only prerequisites are a standard graduate course in probability theory and some familiarity with discrete-paramet

  18. Simultaneous formation of multiscale hierarchical surface morphologies through sequential wrinkling and folding

    Science.gov (United States)

    Wang, Yu; Sun, Qingyang; Xiao, Jianliang

    2018-02-01

    Highly organized hierarchical surface morphologies possess various intriguing properties that could find important potential applications. In this paper, we demonstrate a facile approach to simultaneously form multiscale hierarchical surface morphologies through sequential wrinkling. This method combines surface wrinkling induced by thermal expansion and mechanical strain on a three-layer structure composed of an aluminum film, a hard Polydimethylsiloxane (PDMS) film, and a soft PDMS substrate. Deposition of the aluminum film on hard PDMS induces biaxial wrinkling due to thermal expansion mismatch, and recovering the prestrain in the soft PDMS substrate leads to wrinkling of the hard PDMS film. In total, three orders of wrinkling patterns form in this process, with wavelength and amplitude spanning 3 orders of magnitude in length scale. By increasing the prestrain in the soft PDMS substrate, a hierarchical wrinkling-folding structure was also obtained. This approach can be easily extended to other thin films for fabrication of multiscale hierarchical surface morphologies with potential applications in different areas.

  19. Exploring the sequential lineup advantage using WITNESS.

    Science.gov (United States)

    Goodsell, Charles A; Gronlund, Scott D; Carlson, Curt A

    2010-12-01

    Advocates claim that the sequential lineup is an improvement over simultaneous lineup procedures, but no formal (quantitatively specified) explanation exists for why it is better. The computational model WITNESS (Clark, Appl Cogn Psychol 17:629-654, 2003) was used to develop theoretical explanations for the sequential lineup advantage. In its current form, WITNESS produced a sequential advantage only by pairing conservative sequential choosing with liberal simultaneous choosing. However, this combination failed to approximate four extant experiments that exhibited large sequential advantages. Two of these experiments became the focus of our efforts because the data were uncontaminated by likely suspect position effects. Decision-based and memory-based modifications to WITNESS approximated the data and produced a sequential advantage. The next step is to evaluate the proposed explanations and modify public policy recommendations accordingly.

  20. Sequential and simultaneous choices: testing the diet selection and sequential choice models.

    Science.gov (United States)

    Freidin, Esteban; Aw, Justine; Kacelnik, Alex

    2009-03-01

    We investigate simultaneous and sequential choices in starlings, using Charnov's Diet Choice Model (DCM) and Shapiro, Siller and Kacelnik's Sequential Choice Model (SCM) to integrate function and mechanism. During a training phase, starlings encountered one food-related option per trial (A, B or R) in random sequence and with equal probability. A and B delivered food rewards after programmed delays (shorter for A), while R ('rejection') moved directly to the next trial without reward. In this phase we measured latencies to respond. In a later, choice, phase, birds encountered the pairs A-B, A-R and B-R, the first implementing a simultaneous choice and the second and third sequential choices. The DCM predicts when R should be chosen to maximize intake rate, and SCM uses latencies of the training phase to predict choices between any pair of options in the choice phase. The predictions of both models coincided, and both successfully predicted the birds' preferences. The DCM does not deal with partial preferences, while the SCM does, and experimental results were strongly correlated to this model's predictions. We believe that the SCM may expose a very general mechanism of animal choice, and that its wider domain of success reflects the greater ecological significance of sequential over simultaneous choices.

  1. An Investigation of the Academic Information Finding and Re-finding Behavior on the Web

    Directory of Open Access Journals (Sweden)

    Hsiao-Tieh Pu

    2014-12-01

    Full Text Available Academic researchers often need and re-use relevant information found after a period of time. This preliminary study used various methods, including experiments, interviews, search log analysis, sequential analysis, and observation to investigate characteristics of academic information finding and re-finding behavior. Overall, the participants in this study entered short queries either in finding or re-finding phases. Comparatively speaking, the participants entered greater number of queries, modified more queries, browsed more web pages, and stayed longer on web pages in the finding phase. On the other hand, in the re-finding phase, they utilized personal information management tools to re-find instead of finding again using search engine, such as checking browsing history; moreover, they tend to input less number of queries and stayed shorter on web pages. In short, the participants interacted more with the retrieval system during the finding phase, while they increased the use of personal information management tools in the re-finding phase. As to the contextual clues used in re-finding phase, the participants used less clues from the target itself, instead, they used indirect clues more often, especially location-related information. Based on the results of sequential analysis, the transition states in the re-finding phase was found to be more complex than those in the finding phase. Web information finding and re-finding behavior is an important and novel area of research. The preliminary results would benefit research on Web information re-finding behavior, and provide useful suggestions for developing personal academic information management systems. [Article content in Chinese

  2. Sequential memory: Binding dynamics

    Science.gov (United States)

    Afraimovich, Valentin; Gong, Xue; Rabinovich, Mikhail

    2015-10-01

    Temporal order memories are critical for everyday animal and human functioning. Experiments and our own experience show that the binding or association of various features of an event together and the maintaining of multimodality events in sequential order are the key components of any sequential memories—episodic, semantic, working, etc. We study a robustness of binding sequential dynamics based on our previously introduced model in the form of generalized Lotka-Volterra equations. In the phase space of the model, there exists a multi-dimensional binding heteroclinic network consisting of saddle equilibrium points and heteroclinic trajectories joining them. We prove here the robustness of the binding sequential dynamics, i.e., the feasibility phenomenon for coupled heteroclinic networks: for each collection of successive heteroclinic trajectories inside the unified networks, there is an open set of initial points such that the trajectory going through each of them follows the prescribed collection staying in a small neighborhood of it. We show also that the symbolic complexity function of the system restricted to this neighborhood is a polynomial of degree L - 1, where L is the number of modalities.

  3. Pattern-Driven Automatic Parallelization

    Directory of Open Access Journals (Sweden)

    Christoph W. Kessler

    1996-01-01

    Full Text Available This article describes a knowledge-based system for automatic parallelization of a wide class of sequential numerical codes operating on vectors and dense matrices, and for execution on distributed memory message-passing multiprocessors. Its main feature is a fast and powerful pattern recognition tool that locally identifies frequently occurring computations and programming concepts in the source code. This tool also works for dusty deck codes that have been "encrypted" by former machine-specific code transformations. Successful pattern recognition guides sophisticated code transformations including local algorithm replacement such that the parallelized code need not emerge from the sequential program structure by just parallelizing the loops. It allows access to an expert's knowledge on useful parallel algorithms, available machine-specific library routines, and powerful program transformations. The partially restored program semantics also supports local array alignment, distribution, and redistribution, and allows for faster and more exact prediction of the performance of the parallelized target code than is usually possible.

  4. Simultaneous Versus Sequential Presentation in Testing Recognition Memory for Faces.

    Science.gov (United States)

    Finley, Jason R; Roediger, Henry L; Hughes, Andrea D; Wahlheim, Christopher N; Jacoby, Larry L

    2015-01-01

    Three experiments examined the issue of whether faces could be better recognized in a simul- taneous test format (2-alternative forced choice [2AFC]) or a sequential test format (yes-no). All experiments showed that when target faces were present in the test, the simultaneous procedure led to superior performance (area under the ROC curve), whether lures were high or low in similarity to the targets. However, when a target-absent condition was used in which no lures resembled the targets but the lures were similar to each other, the simultaneous procedure yielded higher false alarm rates (Experiments 2 and 3) and worse overall performance (Experi- ment 3). This pattern persisted even when we excluded responses that participants opted to withhold rather than volunteer. We conclude that for the basic recognition procedures used in these experiments, simultaneous presentation of alternatives (2AFC) generally leads to better discriminability than does sequential presentation (yes-no) when a target is among the alterna- tives. However, our results also show that the opposite can occur when there is no target among the alternatives. An important future step is to see whether these patterns extend to more realistic eyewitness lineup procedures. The pictures used in the experiment are available online at http://www.press.uillinois.edu/journals/ajp/media/testing_recognition/.

  5. On the uniqueness of color patterns in raptor feathers

    Science.gov (United States)

    Ellis, D.H.

    2009-01-01

    For this study, I compared sequentially molted feathers for a few captive raptors from year to year and symmetrically matched feathers (left/right pairs) for many raptors to see if color patterns of sequential feather pairs were identical or if symmetrical pairs were mirror-image identical. Feather pairs were found to be identical only when without color pattern (e.g., the all-white rectrices of Bald Eagles [Haliaeetus leucocephalus]). Complex patterns were not closely matched, but some simple patterns were sometimes closely matched, although not identical. Previous claims that complex color patterns in feather pairs are fingerprint-identical (and therefore that molted feathers from wild raptors can be used to identify breeding adults from year to year with certainty) were found to be untrue: each feather is unique. Although it is unwise to be certain of bird of origin using normal feathers, abnormal feathers can often be so used. ?? 2009 The Raptor Research Foundation, Inc.

  6. Sequential Probability Ration Tests : Conservative and Robust

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; Shi, Wen

    2017-01-01

    In practice, most computers generate simulation outputs sequentially, so it is attractive to analyze these outputs through sequential statistical methods such as sequential probability ratio tests (SPRTs). We investigate several SPRTs for choosing between two hypothesized values for the mean output

  7. A new method for discovering behavior patterns among animal movements

    Science.gov (United States)

    Wang, Y.; Luo, Ze; Takekawa, John Y.; Prosser, Diann J.; Xiong, Y.; Newman, S.; Xiao, X.; Batbayar, N.; Spragens, Kyle A.; Balachandran, S.; Yan, B.

    2016-01-01

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets.

  8. Mobility of radionuclides based on sequential extraction of soils

    International Nuclear Information System (INIS)

    Salbu, B.; Oughton, D.H.; Lien, H.N.; Oestby, G.; Strand, P.

    1992-01-01

    Since 1989, core samples of soil and vegetation from semi-natural pastures have been collected at selected sites in Norway during the growing season. The activity concentrations in soil and vegetation as well as transfer coefficients vary significantly between regions, within regions and even within sampling plot areas. In order to differentiate between mobil and inert fractions of radioactive and stable isotopes of Cs and Sr in soils, samples were extracted sequentially using agents with increasing dissolution power. The reproducibility of the sequential extraction technique is good and the data obtained seems most informative. As the distribution pattern for radioactive and stable isotopes of Cs and Sr are similar, a high degree of isotopic exchange is indicated. Based on easily leachable fractions, mobility factors are calculated. In general the mobility of 90 Sr is higher than for 137 Cs. Mobility factors are not significantly influenced by seasonal variations, but a decrease in the mobile fraction in soil with time is indicated. Mobility factors should be considered useful for modelling purposes. (au)

  9. Sequential Product of Quantum Effects: An Overview

    Science.gov (United States)

    Gudder, Stan

    2010-12-01

    This article presents an overview for the theory of sequential products of quantum effects. We first summarize some of the highlights of this relatively recent field of investigation and then provide some new results. We begin by discussing sequential effect algebras which are effect algebras endowed with a sequential product satisfying certain basic conditions. We then consider sequential products of (discrete) quantum measurements. We next treat transition effect matrices (TEMs) and their associated sequential product. A TEM is a matrix whose entries are effects and whose rows form quantum measurements. We show that TEMs can be employed for the study of quantum Markov chains. Finally, we prove some new results concerning TEMs and vector densities.

  10. Optimal Sequential Rules for Computer-Based Instruction.

    Science.gov (United States)

    Vos, Hans J.

    1998-01-01

    Formulates sequential rules for adapting the appropriate amount of instruction to learning needs in the context of computer-based instruction. Topics include Bayesian decision theory, threshold and linear-utility structure, psychometric model, optimal sequential number of test questions, and an empirical example of sequential instructional…

  11. Impact of sequential disorder on the scaling behavior of airplane boarding time

    Science.gov (United States)

    Baek, Yongjoo; Ha, Meesoon; Jeong, Hawoong

    2013-05-01

    Airplane boarding process is an example where disorder properties of the system are relevant to the emergence of universality classes. Based on a simple model, we present a systematic analysis of finite-size effects in boarding time, and propose a comprehensive view of the role of sequential disorder in the scaling behavior of boarding time against the plane size. Using numerical simulations and mathematical arguments, we find how the scaling behavior depends on the number of seat columns and the range of sequential disorder. Our results show that new scaling exponents can arise as disorder is localized to varying extents.

  12. Bursts and heavy tails in temporal and sequential dynamics of foraging decisions.

    Directory of Open Access Journals (Sweden)

    Kanghoon Jung

    2014-08-01

    Full Text Available A fundamental understanding of behavior requires predicting when and what an individual will choose. However, the actual temporal and sequential dynamics of successive choices made among multiple alternatives remain unclear. In the current study, we tested the hypothesis that there is a general bursting property in both the timing and sequential patterns of foraging decisions. We conducted a foraging experiment in which rats chose among four different foods over a continuous two-week time period. Regarding when choices were made, we found bursts of rapidly occurring actions, separated by time-varying inactive periods, partially based on a circadian rhythm. Regarding what was chosen, we found sequential dynamics in affective choices characterized by two key features: (a a highly biased choice distribution; and (b preferential attachment, in which the animals were more likely to choose what they had previously chosen. To capture the temporal dynamics, we propose a dual-state model consisting of active and inactive states. We also introduce a satiation-attainment process for bursty activity, and a non-homogeneous Poisson process for longer inactivity between bursts. For the sequential dynamics, we propose a dual-control model consisting of goal-directed and habit systems, based on outcome valuation and choice history, respectively. This study provides insights into how the bursty nature of behavior emerges from the interaction of different underlying systems, leading to heavy tails in the distribution of behavior over time and choices.

  13. Bursts and Heavy Tails in Temporal and Sequential Dynamics of Foraging Decisions

    Science.gov (United States)

    Jung, Kanghoon; Jang, Hyeran; Kralik, Jerald D.; Jeong, Jaeseung

    2014-01-01

    A fundamental understanding of behavior requires predicting when and what an individual will choose. However, the actual temporal and sequential dynamics of successive choices made among multiple alternatives remain unclear. In the current study, we tested the hypothesis that there is a general bursting property in both the timing and sequential patterns of foraging decisions. We conducted a foraging experiment in which rats chose among four different foods over a continuous two-week time period. Regarding when choices were made, we found bursts of rapidly occurring actions, separated by time-varying inactive periods, partially based on a circadian rhythm. Regarding what was chosen, we found sequential dynamics in affective choices characterized by two key features: (a) a highly biased choice distribution; and (b) preferential attachment, in which the animals were more likely to choose what they had previously chosen. To capture the temporal dynamics, we propose a dual-state model consisting of active and inactive states. We also introduce a satiation-attainment process for bursty activity, and a non-homogeneous Poisson process for longer inactivity between bursts. For the sequential dynamics, we propose a dual-control model consisting of goal-directed and habit systems, based on outcome valuation and choice history, respectively. This study provides insights into how the bursty nature of behavior emerges from the interaction of different underlying systems, leading to heavy tails in the distribution of behavior over time and choices. PMID:25122498

  14. Sequential stenotic strictures of the small bowel leading to obstruction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Small bowel obstructions (SBOs) are primarily caused by adhesions, hernias, neoplasms, or inflammatory strictures. Intraluminal strictures are an uncommon cause of SBO. This report describes our findings in a unique case of sequential, stenotic intraluminal strictures of the small intestine, discusses the differential diagnosis of intraluminal intestinal strictures, and reviews the literature regarding intraluminal pathology.

  15. Computation of Stackelberg Equilibria of Finite Sequential Games

    DEFF Research Database (Denmark)

    Bosanski, Branislav; Branzei, Simina; Hansen, Kristoffer Arnsfelt

    2015-01-01

    The Stackelberg equilibrium is a solution concept that describes optimal strategies to commit to: Player~1 (the leader) first commits to a strategy that is publicly announced, then Player~2 (the follower) plays a best response to the leader's choice. We study Stackelberg equilibria in finite...... sequential (i.e., extensive-form) games and provide new exact algorithms, approximate algorithms, and hardness results for finding equilibria for several classes of such two-player games....

  16. Quantum Inequalities and Sequential Measurements

    International Nuclear Information System (INIS)

    Candelpergher, B.; Grandouz, T.; Rubinx, J.L.

    2011-01-01

    In this article, the peculiar context of sequential measurements is chosen in order to analyze the quantum specificity in the two most famous examples of Heisenberg and Bell inequalities: Results are found at some interesting variance with customary textbook materials, where the context of initial state re-initialization is described. A key-point of the analysis is the possibility of defining Joint Probability Distributions for sequential random variables associated to quantum operators. Within the sequential context, it is shown that Joint Probability Distributions can be defined in situations where not all of the quantum operators (corresponding to random variables) do commute two by two. (authors)

  17. Support for distinct subcomponents of spatial working memory: a double dissociation between spatial-simultaneous and spatial-sequential performance in unilateral neglect.

    Science.gov (United States)

    Wansard, Murielle; Bartolomeo, Paolo; Bastin, Christine; Segovia, Fermín; Gillet, Sophie; Duret, Christophe; Meulemans, Thierry

    2015-01-01

    Over the last decade, many studies have demonstrated that visuospatial working memory (VSWM) can be divided into separate subsystems dedicated to the retention of visual patterns and their serial order. Impaired VSWM has been suggested to exacerbate left visual neglect in right-brain-damaged individuals. The aim of this study was to investigate the segregation between spatial-sequential and spatial-simultaneous working memory in individuals with neglect. We demonstrated that patterns of results on these VSWM tasks can be dissociated. Spatial-simultaneous and sequential aspects of VSWM can be selectively impaired in unilateral neglect. Our results support the hypothesis of multiple VSWM subsystems, which should be taken into account to better understand neglect-related deficits.

  18. Effect of sequential isoproturon pulse exposure on Scenedesmus vacuolatus.

    Science.gov (United States)

    Vallotton, Nathalie; Eggen, Rik Ilda Lambertus; Chèvre, Nathalie

    2009-04-01

    Aquatic organisms are typically exposed to fluctuating concentrations of herbicides in streams. To assess the effects on algae of repeated peak exposure to the herbicide isoproturon, we subjected the alga Scenedesmus vacuolatus to two sequential pulse exposure scenarios. Effects on growth and on the inhibition of the effective quantum yield of photosystem II (PSII) were measured. In the first scenario, algae were exposed to short, 5-h pulses at high isoproturon concentrations (400 and 1000 microg/l), each followed by a recovery period of 18 h, while the second scenario consisted of 22.5-h pulses at lower concentrations (60 and 120 microg/l), alternating with short recovery periods (1.5 h). In addition, any changes in the sensitivity of the algae to isoproturon following sequential pulses were examined by determining the growth rate-EC(50) prior to and following exposure. In both exposure scenarios, we found that algal growth and its effective quantum yield were systematically inhibited during the exposures and that these effects were reversible. Sequential pulses to isoproturon could be considered a sequence of independent events. Nevertheless, a consequence of inhibited growth during the repeated exposures is the cumulative decrease in biomass production. Furthermore, in the second scenario, when the sequence of long pulses began to approach a scenario of continuous exposure, a slight increase in the tolerance of the algae to isoproturon was observed. These findings indicated that sequential pulses do affect algae during each pulse exposure, even if algae recover between the exposures. These observations could support an improved risk assessment of fluctuating exposures to reversibly acting herbicides.

  19. Sequential Generalized Transforms on Function Space

    Directory of Open Access Journals (Sweden)

    Jae Gil Choi

    2013-01-01

    Full Text Available We define two sequential transforms on a function space Ca,b[0,T] induced by generalized Brownian motion process. We then establish the existence of the sequential transforms for functionals in a Banach algebra of functionals on Ca,b[0,T]. We also establish that any one of these transforms acts like an inverse transform of the other transform. Finally, we give some remarks about certain relations between our sequential transforms and other well-known transforms on Ca,b[0,T].

  20. PC_Eyewitness and the sequential superiority effect: computer-based lineup administration.

    Science.gov (United States)

    MacLin, Otto H; Zimmerman, Laura A; Malpass, Roy S

    2005-06-01

    Computer technology has become an increasingly important tool for conducting eyewitness identifications. In the area of lineup identifications, computerized administration offers several advantages for researchers and law enforcement. PC_Eyewitness is designed specifically to administer lineups. To assess this new lineup technology, two studies were conducted in order to replicate the results of previous studies comparing simultaneous and sequential lineups. One hundred twenty university students participated in each experiment. Experiment 1 used traditional paper-and-pencil lineup administration methods to compare simultaneous to sequential lineups. Experiment 2 used PC_Eyewitness to administer simultaneous and sequential lineups. The results of these studies were compared to the meta-analytic results reported by N. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001). No differences were found between paper-and-pencil and PC_Eyewitness lineup administration methods. The core findings of the N. Steblay et al. (2001) meta-analysis were replicated by both administration procedures. These results show that computerized lineup administration using PC_Eyewitness is an effective means for gathering eyewitness identification data.

  1. Forced Sequence Sequential Decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Paaske, Erik

    1998-01-01

    We describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1/4 and memory M=23, and block interleaved outer Reed-Solomon (RS) codes with nonuniform profile. With this scheme decoding with good performance is possible as low...... as Eb/N0=0.6 dB, which is about 1.25 dB below the signal-to-noise ratio (SNR) that marks the cutoff rate for the full system. Accounting for about 0.45 dB due to the outer codes, sequential decoding takes place at about 1.7 dB below the SNR cutoff rate for the convolutional code. This is possible since...... the iteration process provides the sequential decoders with side information that allows a smaller average load and minimizes the probability of computational overflow. Analytical results for the probability that the first RS word is decoded after C computations are presented. These results are supported...

  2. Decoding restricted participation in sequential electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Knaut, Andreas; Paschmann, Martin

    2017-06-15

    Restricted participation in sequential markets may cause high price volatility and welfare losses. In this paper we therefore analyze the drivers of restricted participation in the German intraday auction which is a short-term electricity market with quarter-hourly products. Applying a fundamental electricity market model with 15-minute temporal resolution, we identify the lack of sub-hourly market coupling being the most relevant driver of restricted participation. We derive a proxy for price volatility and find that full market coupling may trigger quarter-hourly price volatility to decrease by a factor close to four.

  3. Sequential probability ratio controllers for safeguards radiation monitors

    International Nuclear Information System (INIS)

    Fehlau, P.E.; Coop, K.L.; Nixon, K.V.

    1984-01-01

    Sequential hypothesis tests applied to nuclear safeguards accounting methods make the methods more sensitive to detecting diversion. The sequential tests also improve transient signal detection in safeguards radiation monitors. This paper describes three microprocessor control units with sequential probability-ratio tests for detecting transient increases in radiation intensity. The control units are designed for three specific applications: low-intensity monitoring with Poisson probability ratios, higher intensity gamma-ray monitoring where fixed counting intervals are shortened by sequential testing, and monitoring moving traffic where the sequential technique responds to variable-duration signals. The fixed-interval controller shortens a customary 50-s monitoring time to an average of 18 s, making the monitoring delay less bothersome. The controller for monitoring moving vehicles benefits from the sequential technique by maintaining more than half its sensitivity when the normal passage speed doubles

  4. Biased lineups: sequential presentation reduces the problem.

    Science.gov (United States)

    Lindsay, R C; Lea, J A; Nosworthy, G J; Fulford, J A; Hector, J; LeVan, V; Seabrook, C

    1991-12-01

    Biased lineups have been shown to increase significantly false, but not correct, identification rates (Lindsay, Wallbridge, & Drennan, 1987; Lindsay & Wells, 1980; Malpass & Devine, 1981). Lindsay and Wells (1985) found that sequential lineup presentation reduced false identification rates, presumably by reducing reliance on relative judgment processes. Five staged-crime experiments were conducted to examine the effect of lineup biases and sequential presentation on eyewitness recognition accuracy. Sequential lineup presentation significantly reduced false identification rates from fair lineups as well as from lineups biased with regard to foil similarity, instructions, or witness attire, and from lineups biased in all of these ways. The results support recommendations that police present lineups sequentially.

  5. Glycerol production by Oenococcus oeni during sequential and simultaneous cultures with wine yeast strains.

    Science.gov (United States)

    Ale, Cesar E; Farías, Marta E; Strasser de Saad, Ana M; Pasteris, Sergio E

    2014-07-01

    Growth and fermentation patterns of Saccharomyces cerevisiae, Kloeckera apiculata, and Oenococcus oeni strains cultured in grape juice medium were studied. In pure, sequential and simultaneous cultures, the strains reached the stationary growth phase between 2 and 3 days. Pure and mixed K. apiculata and S. cerevisiae cultures used mainly glucose, producing ethanol, organic acids, and 4.0 and 0.1 mM glycerol, respectively. In sequential cultures, O. oeni achieved about 1 log unit at 3 days using mainly fructose and L-malic acid. Highest sugars consumption was detected in K. apiculata supernatants, lactic acid being the major end-product. 8.0 mM glycerol was found in 6-day culture supernatants. In simultaneous cultures, total sugars and L-malic acid were used at 3 days and 98% of ethanol and glycerol were detected. This study represents the first report of the population dynamics and metabolic behavior of yeasts and O. oeni in sequential and simultaneous cultures and contributes to the selection of indigenous strains to design starter cultures for winemaking, also considering the inclusion of K. apiculata. The sequential inoculation of yeasts and O. oeni would enhance glycerol production, which confers desirable organoleptic characteristics to wines, while organic acids levels would not affect their sensory profile. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. How to Organize Sequential Auctions : Results of a Natural Experiment by Christie's

    NARCIS (Netherlands)

    Ginsburgh, V.; van Ours, J.C.

    2003-01-01

    In empirical studies of sequential auctions of identical objects prices have been found to decline.We study auctions of ancient Chinese porcelain recovered from shipwrecks.In these auctions there are very long sequences of lots of identical objects.We find that the average price decline is smaller

  7. Lineup composition, suspect position, and the sequential lineup advantage.

    Science.gov (United States)

    Carlson, Curt A; Gronlund, Scott D; Clark, Steven E

    2008-06-01

    N. M. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001) argued that sequential lineups reduce the likelihood of mistaken eyewitness identification. Experiment 1 replicated the design of R. C. L. Lindsay and G. L. Wells (1985), the first study to show the sequential lineup advantage. However, the innocent suspect was chosen at a lower rate in the simultaneous lineup, and no sequential lineup advantage was found. This led the authors to hypothesize that protection from a sequential lineup might emerge only when an innocent suspect stands out from the other lineup members. In Experiment 2, participants viewed a simultaneous or sequential lineup with either the guilty suspect or 1 of 3 innocent suspects. Lineup fairness was varied to influence the degree to which a suspect stood out. A sequential lineup advantage was found only for the unfair lineups. Additional analyses of suspect position in the sequential lineups showed an increase in the diagnosticity of suspect identifications as the suspect was placed later in the sequential lineup. These results suggest that the sequential lineup advantage is dependent on lineup composition and suspect position. (c) 2008 APA, all rights reserved

  8. Finding Hidden Location Patterns of Two Competitive Supermarkets in Thailand

    Science.gov (United States)

    Khumsri, Jinattaporn; Fujihara, Akihiro

    There are two famous supermarkets in Thailand: Big C and Lotus. They are the highest competitive supermarkets whose hold the most market share by lots of promotions and also gather all convenience services including banking, restaurant, and others. In recent years, they gradually expand their stores and they take a similar strategy to determine where to locate a store. It is important for them to consider store allocation to obtain new customers efficiently. To consider this, we gather geographical locations of these supermarkets from Twitter using Twitter API. We gathered tweets having these supermarket names and geotags for seven months. To extract hidden location patterns from gathered data, we introduce location motif which is a directed subgraph whose edges are linked to every pair of the shortest-distance opponent node. We investigate every possible configuration of location motif when they have a small number of nodes and find that the configuration increases exponentially. We also visualize location motifs generated from gathered data on the map of Thailand and count the frequency of observed location motifs. As a result, we find that even if the possible location motifs exponentially increase as the number of nodes grows, limited location motifs can be observed. Using location motif, we successfully find an evidence of biased store allocation in reality.

  9. Immediately sequential bilateral cataract surgery: advantages and disadvantages.

    Science.gov (United States)

    Singh, Ranjodh; Dohlman, Thomas H; Sun, Grace

    2017-01-01

    The number of cataract surgeries performed globally will continue to rise to meet the needs of an aging population. This increased demand will require healthcare systems and providers to find new surgical efficiencies while maintaining excellent surgical outcomes. Immediately sequential bilateral cataract surgery (ISBCS) has been proposed as a solution and is increasingly being performed worldwide. The purpose of this review is to discuss the advantages and disadvantages of ISBCS. When appropriate patient selection occurs and guidelines are followed, ISBCS is comparable with delayed sequential bilateral cataract surgery in long-term patient satisfaction, visual acuity and complication rates. In addition, the risk of bilateral postoperative endophthalmitis and concerns of poorer refractive outcomes have not been supported by the literature. ISBCS is cost-effective for the patient, healthcare payors and society, but current reimbursement models in many countries create significant financial barriers for facilities and surgeons. As demand for cataract surgery rises worldwide, ISBCS will become increasingly important as an alternative to delayed sequential bilateral cataract surgery. Advantages include potentially decreased wait times for surgery, patient convenience and cost savings for healthcare payors. Although they are comparable in visual acuity and complication rates, hurdles that prevent wide adoption include liability concerns as ISBCS is not an established standard of care, economic constraints for facilities and surgeons and inability to fine-tune intraocular lens selection in the second eye. Given these considerations, an open discussion regarding the advantages and disadvantages of ISBCS is important for appropriate patient selection.

  10. Tradable permit allocations and sequential choice

    Energy Technology Data Exchange (ETDEWEB)

    MacKenzie, Ian A. [Centre for Economic Research, ETH Zuerich, Zurichbergstrasse 18, 8092 Zuerich (Switzerland)

    2011-01-15

    This paper investigates initial allocation choices in an international tradable pollution permit market. For two sovereign governments, we compare allocation choices that are either simultaneously or sequentially announced. We show sequential allocation announcements result in higher (lower) aggregate emissions when announcements are strategic substitutes (complements). Whether allocation announcements are strategic substitutes or complements depends on the relationship between the follower's damage function and governments' abatement costs. When the marginal damage function is relatively steep (flat), allocation announcements are strategic substitutes (complements). For quadratic abatement costs and damages, sequential announcements provide a higher level of aggregate emissions. (author)

  11. Phenomenology of the next sequential lepton

    International Nuclear Information System (INIS)

    Rizzo, T.G.

    1980-01-01

    We consider the phenomenology of a sequential, charged lepton in the mass range 6 --13 GeV. We find the semileptonic branching ratio of such a lepton to be approx. 13%; the dominant two-body modes are found to include the decay L → ν/sub L/F* with a branching ratio approx. 6%. In this analysis we assume that the mass of the lepton under consideration is lighter than the t quark such that decays such as L → ν/sub L/t-barq, where q= (d, s, or b) are kinematically forbidden. We also find that decays such as L → ν/sub L/B* (c-barb) can also be as large as approx. 6% depending on the mixing angles; the lifetime of such a lepton is found to be approx. 2.6 x 10 -12 M/sub L/ -5 sec, where M/sub L/ is in GeV

  12. Applying the minimax principle to sequential mastery testing

    NARCIS (Netherlands)

    Vos, Hendrik J.

    2002-01-01

    The purpose of this paper is to derive optimal rules for sequential mastery tests. In a sequential mastery test, the decision is to classify a subject as a master, a nonmaster, or to continue sampling and administering another random item. The framework of minimax sequential decision theory (minimum

  13. Colonic uptake patterns of F-18-FDG PET in asymptomatic adults: correlation with colonoscopic findings

    International Nuclear Information System (INIS)

    Pai, M.; Cho, Y.; Shim, K

    2004-01-01

    Physiologic intestinal FDG uptake is frequently observed in asymptomatic individuals for cancer screening FDG PET. Colonic FDG accumulation is a well-known confusing findings that interfere true cancer detection or cause false positive. The aim of this study was to evaluate the pattern and intensity of colonic uptake in whole body FDG PET in asymptomatic healthy adults and to correlate those with colonoscopic findings. We reviewed retrospectively 64 subjects (age: 27-87, M:F = 31:33) who underwent both FDG PET and colonoscopy for cancer screening. FDG uptake pattern was classified as focal, segmental and diffuse. Maximum SUV were measured. The PET results were compared with colonoscopic and histologic findings. In 34 patients FDG bowel uptake was interpreted as diffuse(group I), in 17 patients as segmental(group II) and in 13 patients as focal uptake(group III). Six adenomas(17.6%, average diameter = 5 mm) were found in group I, 7 adenomas (41.1%, 5.57 mm) in group II and 4 adenomas and 1 adenocarcinoma (30.7%, 16.4 mm) in group III. There was no difference in averages of SUV between patients with adenoma and with negative colonoscopic results in each group of intestinal FDG pattern (group I: 1.675±1.15 vs 1.94±0.62, group II: 4.78±3.66 vs 4.23±1.13, group III: 6.50±4.68 vs 4.1±1.01). Large adenomas( >1 cm) were detected more frequently in group III (4 out of 5) rather than in group II (1 out of 7) or group I (none) and had higher SUV (6.30±4.84) than small adenomas (3.74±3.23). In group III, 4 patients without adenomas were non-physiologic(30.7%, 2 intestinal tuberculosis, 2 mucosal ulcer). Focal FDG uptake is associated more often with large adenoma and other pathologic findings in colonoscopy. Segmental uptake cannot discriminate presence of adenoma from negative results, while diffuse pattern may imply normal or having small adenomas

  14. Patterns of FDG uptake in stomach on F-18 FDG positron emission tomography: correlation with endoscopic findings

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Min Jeong; Cheon, Gi Jeong; Lee, Sang Woo; Byun, Byung Hyun; Kim, Sung Eun; Kim, Yu Chul; Choi, Chang Woon; Lim, Sang Moo [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2005-10-15

    We often find variable degrees of FDG uptake and patterns in stomach, which can make difficult to distinguish physiologic uptake from pathologic uptake on FDG PET. The purpose of this study was to find out the significant findings of stomach on FDG PET. Thirty-eight patients who underwent both FDG PET and endoscopy within one week from Jun. 2003, to Aug. 2004 were included in this study. We reviewed 38 patients (18 for medical check up, 15 for work up of other malignancies, and 5 for the evaluation of stomach lesion). Their mean age was 56 years old (range:32 {approx} 79), men and women were 28 and 10, respectively. Two nuclear physicians evaluated five parameters on FDG PET findings of stomach with a consensus: 1) visual grades 2) maximum SUV (max.SUV) 3) focal 4) diffuse and 5) asymmetric patterns. We correlated the lesions of FDG PET findings of stomach with those of endoscopy. We considered more than equivocal findings on FDG PET as positive. The six of 38 patients were proven as malignant lesions by endoscopic biopsy and others were inflammatory lesions (ulcer in 3, chronic atrophic gastritis in 12, uncommon forms of gastritis in 5), non-inflammatory lesions (n=3), and normal stomach (n=9). By the visual analysis, malignant lesions had higher FDG uptake than the others. The max.SUV of malignant lesions was 7.95 {+-} 4.83 which was significantly higher than the other benign lesions (2.9 {+-} 0.69 in ulcer, 3.08 {+-} 1.2 in chronic atrophic gastritis, 3.2 {+-} 1.49 in uncommon forms of gastritis ( {rho} =0.044). In the appearance of stomach on FDG PET, malignant lesions were shown focal (5 of 6) and benign inflammatory lesions were shown diffuse (9 of 20) and asymmetric (14 of 20). Benign lesions and normal stomach were shown variable degrees of uptake and patterns. Some cases of benign inflammatory lesions such as ulcer and gastritis were shown focal and mimicked cancerous lesions (4 of 15). Gastric malignant lesions had higher FDG uptake and focal pattern

  15. Patterns of FDG uptake in stomach on F-18 FDG positron emission tomography: correlation with endoscopic findings

    International Nuclear Information System (INIS)

    Chae, Min Jeong; Cheon, Gi Jeong; Lee, Sang Woo; Byun, Byung Hyun; Kim, Sung Eun; Kim, Yu Chul; Choi, Chang Woon; Lim, Sang Moo

    2005-01-01

    We often find variable degrees of FDG uptake and patterns in stomach, which can make difficult to distinguish physiologic uptake from pathologic uptake on FDG PET. The purpose of this study was to find out the significant findings of stomach on FDG PET. Thirty-eight patients who underwent both FDG PET and endoscopy within one week from Jun. 2003, to Aug. 2004 were included in this study. We reviewed 38 patients (18 for medical check up, 15 for work up of other malignancies, and 5 for the evaluation of stomach lesion). Their mean age was 56 years old (range:32 ∼ 79), men and women were 28 and 10, respectively. Two nuclear physicians evaluated five parameters on FDG PET findings of stomach with a consensus: 1) visual grades 2) maximum SUV (max.SUV) 3) focal 4) diffuse and 5) asymmetric patterns. We correlated the lesions of FDG PET findings of stomach with those of endoscopy. We considered more than equivocal findings on FDG PET as positive. The six of 38 patients were proven as malignant lesions by endoscopic biopsy and others were inflammatory lesions (ulcer in 3, chronic atrophic gastritis in 12, uncommon forms of gastritis in 5), non-inflammatory lesions (n=3), and normal stomach (n=9). By the visual analysis, malignant lesions had higher FDG uptake than the others. The max.SUV of malignant lesions was 7.95 ± 4.83 which was significantly higher than the other benign lesions (2.9 ± 0.69 in ulcer, 3.08 ± 1.2 in chronic atrophic gastritis, 3.2 ± 1.49 in uncommon forms of gastritis ( ρ =0.044). In the appearance of stomach on FDG PET, malignant lesions were shown focal (5 of 6) and benign inflammatory lesions were shown diffuse (9 of 20) and asymmetric (14 of 20). Benign lesions and normal stomach were shown variable degrees of uptake and patterns. Some cases of benign inflammatory lesions such as ulcer and gastritis were shown focal and mimicked cancerous lesions (4 of 15). Gastric malignant lesions had higher FDG uptake and focal pattern. However, benign

  16. Classical and sequential limit analysis revisited

    Science.gov (United States)

    Leblond, Jean-Baptiste; Kondo, Djimédo; Morin, Léo; Remmal, Almahdi

    2018-04-01

    Classical limit analysis applies to ideal plastic materials, and within a linearized geometrical framework implying small displacements and strains. Sequential limit analysis was proposed as a heuristic extension to materials exhibiting strain hardening, and within a fully general geometrical framework involving large displacements and strains. The purpose of this paper is to study and clearly state the precise conditions permitting such an extension. This is done by comparing the evolution equations of the full elastic-plastic problem, the equations of classical limit analysis, and those of sequential limit analysis. The main conclusion is that, whereas classical limit analysis applies to materials exhibiting elasticity - in the absence of hardening and within a linearized geometrical framework -, sequential limit analysis, to be applicable, strictly prohibits the presence of elasticity - although it tolerates strain hardening and large displacements and strains. For a given mechanical situation, the relevance of sequential limit analysis therefore essentially depends upon the importance of the elastic-plastic coupling in the specific case considered.

  17. On Modeling Large-Scale Multi-Agent Systems with Parallel, Sequential and Genuinely Asynchronous Cellular Automata

    International Nuclear Information System (INIS)

    Tosic, P.T.

    2011-01-01

    We study certain types of Cellular Automata (CA) viewed as an abstraction of large-scale Multi-Agent Systems (MAS). We argue that the classical CA model needs to be modified in several important respects, in order to become a relevant and sufficiently general model for the large-scale MAS, and so that thus generalized model can capture many important MAS properties at the level of agent ensembles and their long-term collective behavior patterns. We specifically focus on the issue of inter-agent communication in CA, and propose sequential cellular automata (SCA) as the first step, and genuinely Asynchronous Cellular Automata (ACA) as the ultimate deterministic CA-based abstract models for large-scale MAS made of simple reactive agents. We first formulate deterministic and nondeterministic versions of sequential CA, and then summarize some interesting configuration space properties (i.e., possible behaviors) of a restricted class of sequential CA. In particular, we compare and contrast those properties of sequential CA with the corresponding properties of the classical (that is, parallel and perfectly synchronous) CA with the same restricted class of update rules. We analytically demonstrate failure of the studied sequential CA models to simulate all possible behaviors of perfectly synchronous parallel CA, even for a very restricted class of non-linear totalistic node update rules. The lesson learned is that the interleaving semantics of concurrency, when applied to sequential CA, is not refined enough to adequately capture the perfect synchrony of parallel CA updates. Last but not least, we outline what would be an appropriate CA-like abstraction for large-scale distributed computing insofar as the inter-agent communication model is concerned, and in that context we propose genuinely asynchronous CA. (author)

  18. Simultaneous versus sequential penetrating keratoplasty and cataract surgery.

    Science.gov (United States)

    Hayashi, Ken; Hayashi, Hideyuki

    2006-10-01

    To compare the surgical outcomes of simultaneous penetrating keratoplasty and cataract surgery with those of sequential surgery. Thirty-nine eyes of 39 patients scheduled for simultaneous keratoplasty and cataract surgery and 23 eyes of 23 patients scheduled for sequential keratoplasty and secondary phacoemulsification surgery were recruited. Refractive error, regular and irregular corneal astigmatism determined by Fourier analysis, and endothelial cell loss were studied at 1 week and 3, 6, and 12 months after combined surgery in the simultaneous surgery group or after subsequent phacoemulsification surgery in the sequential surgery group. At 3 and more months after surgery, mean refractive error was significantly greater in the simultaneous surgery group than in the sequential surgery group, although no difference was seen at 1 week. The refractive error at 12 months was within 2 D of that targeted in 15 eyes (39%) in the simultaneous surgery group and within 2 D in 16 eyes (70%) in the sequential surgery group; the incidence was significantly greater in the sequential group (P = 0.0344). The regular and irregular astigmatism was not significantly different between the groups at 3 and more months after surgery. No significant difference was also found in the percentage of endothelial cell loss between the groups. Although corneal astigmatism and endothelial cell loss were not different, refractive error from target refraction was greater after simultaneous keratoplasty and cataract surgery than after sequential surgery, indicating a better outcome after sequential surgery than after simultaneous surgery.

  19. When good is stickier than bad: Understanding gain/loss asymmetries in sequential framing effects.

    Science.gov (United States)

    Sparks, Jehan; Ledgerwood, Alison

    2017-08-01

    Considerable research has demonstrated the power of the current positive or negative frame to shape people's current judgments. But humans must often learn about positive and negative information as they encounter that information sequentially over time. It is therefore crucial to consider the potential importance of sequencing when developing an understanding of how humans think about valenced information. Indeed, recent work looking at sequentially encountered frames suggests that some frames can linger outside the context in which they are first encountered, sticking in the mind so that subsequent frames have a muted effect. The present research builds a comprehensive account of sequential framing effects in both the loss and the gain domains. After seeing information about a potential gain or loss framed in positive terms or negative terms, participants saw the same issue reframed in the opposing way. Across 5 studies and 1566 participants, we find accumulating evidence for the notion that in the gain domain, positive frames are stickier than negative frames for novel but not familiar scenarios, whereas in the loss domain, negative frames are always stickier than positive frames. Integrating regulatory focus theory with the literatures on negativity dominance and positivity offset, we develop a new and comprehensive account of sequential framing effects that emphasizes the adaptive value of positivity and negativity biases in specific contexts. Our findings highlight the fact that research conducted solely in the loss domain risks painting an incomplete and oversimplified picture of human bias and suggest new directions for future research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Trial Sequential Methods for Meta-Analysis

    Science.gov (United States)

    Kulinskaya, Elena; Wood, John

    2014-01-01

    Statistical methods for sequential meta-analysis have applications also for the design of new trials. Existing methods are based on group sequential methods developed for single trials and start with the calculation of a required information size. This works satisfactorily within the framework of fixed effects meta-analysis, but conceptual…

  1. Sequentially pulsed traveling wave accelerator

    Science.gov (United States)

    Caporaso, George J [Livermore, CA; Nelson, Scott D [Patterson, CA; Poole, Brian R [Tracy, CA

    2009-08-18

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  2. Enhancing pattern of gastric carcinoma at dynamic incremental CT: correlation with gross and histologic findings

    International Nuclear Information System (INIS)

    Shin, Hong Seop; Lee, Dong Ho; Kim, Yoon Hwa; Ko, Young Tae; Lim, Joo Won; Yoon, Yup

    1996-01-01

    To evaluate the enhancing pattern of gastric carcinomas at dynamic incremental CT and to correlate it with pathologic findings. We retrospectively evaluated the enhancement pattern of stomach cancer on dynamic incremental CT of the 78 patients. All the lesions had been pathologically proved after surgery. The enhancement pattern was categorized as good or poor in the early phase;homogeneous, heterogeneous or ring enhancement;the presence or absence of delayed enhancement. There were 16 cases of early gastric cancer (EGC), and 62 cases of advanced gastric cancer(AGC). The Borrmann type of AGC were 1(n=1), 2(n=20), 3=(n=32), 4(n=8) and 5(n=1). The histologic patterns of AGC were tubular(n=49), signet ring cell(n=10), and mucinous(n=3). The enhancing patterns were compared with gross and histologic findings and delayed enhancement was correlated with pathologic evidence of desmoplasia. Good enhancement of tumor was seen in 24/41cases (58.5%) with AGC Borrmann type 3-5, in 6/21(28.6%) with AGC Borrmann type 1-2, and in 3/16(18.8%) with EGC (P<.05). By histologic pattern, good enhancement of tumor was seen in 8/10(80%) with signet ring cell type, in 21/49(42.9%) with tubular type, and in 1/3(33.3%) with mucinous type(P<.05). EGC was homogeneously enhanced in 14/16cases (87.5%), but AGC was heterogeneously enhanced in 33/62(53.2%), respectively(P<.01). There was no significant correlation between delayed enhancement and the presence of desmoplasia. AGC Borrmann type 3-5 and signet ring cell type have a tendency to show good enhancement and EGC is more homogeneously enhanced at dynamic incremental CT

  3. VIPRAM_L1CMS: a 2-Tier 3D Architecture for Pattern Recognition for Track Finding

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, J. R. [Fermilab; Joshi, Joshi,S. [Northwestern U.; Liu, Liu, [Fermilab; Olsen, J. [Fermilab; Shenai, A. [Fermilab

    2017-06-15

    In HEP tracking trigger applications, flagging an individual detector hit is not important. Rather, the path of a charged particle through many detector layers is what must be found. Moreover, given the increased luminosity projected for future LHC experiments, this type of track finding will be required within the Level 1 Trigger system. This means that future LHC experiments require not just a chip capable of high-speed track finding but also one with a high-speed readout architecture. VIPRAM_L1CMS is 2-Tier Vertically Integrated chip designed to fulfill these requirements. It is a complete pipelined Pattern Recognition Associative Memory (PRAM) architecture including pattern recognition, result sparsification, and readout for Level 1 trigger applications in CMS with 15-bit wide detector addresses and eight detector layers included in the track finding. Pattern recognition is based on classic Content Addressable Memories with a Current Race Scheme to reduce timing complexity and a 4-bit Selective Precharge to minimize power consumption. VIPRAM_L1CMS uses a pipelined set of priority-encoded binary readout structures to sparsify and readout active road flags at frequencies of at least 100MHz. VIPRAM_L1CMS is designed to work directly with the Pulsar2b Architecture.

  4. Improving multiple-point-based a priori models for inverse problems by combining Sequential Simulation with the Frequency Matching Method

    DEFF Research Database (Denmark)

    Cordua, Knud Skou; Hansen, Thomas Mejer; Lange, Katrine

    In order to move beyond simplified covariance based a priori models, which are typically used for inverse problems, more complex multiple-point-based a priori models have to be considered. By means of marginal probability distributions ‘learned’ from a training image, sequential simulation has...... proven to be an efficient way of obtaining multiple realizations that honor the same multiple-point statistics as the training image. The frequency matching method provides an alternative way of formulating multiple-point-based a priori models. In this strategy the pattern frequency distributions (i.......e. marginals) of the training image and a subsurface model are matched in order to obtain a solution with the same multiple-point statistics as the training image. Sequential Gibbs sampling is a simulation strategy that provides an efficient way of applying sequential simulation based algorithms as a priori...

  5. Immediate Sequential Bilateral Cataract Surgery

    DEFF Research Database (Denmark)

    Kessel, Line; Andresen, Jens; Erngaard, Ditte

    2015-01-01

    The aim of the present systematic review was to examine the benefits and harms associated with immediate sequential bilateral cataract surgery (ISBCS) with specific emphasis on the rate of complications, postoperative anisometropia, and subjective visual function in order to formulate evidence......-based national Danish guidelines for cataract surgery. A systematic literature review in PubMed, Embase, and Cochrane central databases identified three randomized controlled trials that compared outcome in patients randomized to ISBCS or bilateral cataract surgery on two different dates. Meta-analyses were...... performed using the Cochrane Review Manager software. The quality of the evidence was assessed using the GRADE method (Grading of Recommendation, Assessment, Development, and Evaluation). We did not find any difference in the risk of complications or visual outcome in patients randomized to ISBCS or surgery...

  6. Use of sequential infiltration synthesis to improve the pattern transfer of PS-b-PLA DSA (Conference Presentation)

    Science.gov (United States)

    Evangelio Araujo, Laura; Fernández-Regúlez, Marta; Chevalier, Xavier; Nicolet, Célia; Cayrefourcq, Ian; Navarro, Christophe; Fleury, Guillaume; Pérez-Murano, Francesc

    2017-03-01

    Directed self-assembly of block copolymers is considered one of the candidates to fulfill the requirements of the next technological nodes [1,2]. Polymer domains are aligned by using a chemical and/or a topographical pre-pattern in which preferential surfaces to one of the two blocks or neutral wetting areas are created. In particular, polystyrene-block-polymetylmethacrylate (PS-b-PMMA) has been extensively studied during the last years showing strong capabilities to define periodic nanostructures. However, the relatively low Flory-Huggins parameter and, the resulting low segregation strength of PS-b-PMMA systems, limit their achievable resolution to around 11 nm [3]. The application of block copolymer on sub-10 nm technologies requires the development of the new block copolymer generation known as high- block copolymers. Additionally, an important requirement for their integration on the lithography roadmap is the capability of selectively remove one of the two blocks. The etch contrast between the two domains is typically low due to their organic chemistry. In this sense, selective sequential infiltration synthesis by ALD into one of the blocks can be used in order to incorporate an inorganic material. The formed organic/inorganic blend sustains better the plasma etching to remove the non-infiltrated organic block. In this contribution, we show the use of high- polystyrene-b-polylactide acid (PS-b-PLA) lamellar block copolymer for line/space applications. PS-b-PLA has a larger Flory-Huggins parameter (=0.218 at room temperature[4]) compared with PS-b-PMMA, allowing the size reduction of the self-assembled domains. The method to control the orientation of the polymer domains is similar to the one typically used for PS-b-PMMA. Chemical contrast and the subsequent alignment of the polymer domains are achieved by the definition of a chemical pre-pattern on a random copolymer PS-r-PMMA (48% of PS) (figure 1). The polymer brush is grafted on the substrate and then

  7. Identification of putative cis-regulatory elements in Cryptosporidium parvum by de novo pattern finding

    Directory of Open Access Journals (Sweden)

    Kissinger Jessica C

    2007-01-01

    Full Text Available Abstract Background Cryptosporidium parvum is a unicellular eukaryote in the phylum Apicomplexa. It is an obligate intracellular parasite that causes diarrhea and is a significant AIDS-related pathogen. Cryptosporidium parvum is not amenable to long-term laboratory cultivation or classical molecular genetic analysis. The parasite exhibits a complex life cycle, a broad host range, and fundamental mechanisms of gene regulation remain unknown. We have used data from the recently sequenced genome of this organism to uncover clues about gene regulation in C. parvum. We have applied two pattern finding algorithms MEME and AlignACE to identify conserved, over-represented motifs in the 5' upstream regions of genes in C. parvum. To support our findings, we have established comparative real-time -PCR expression profiles for the groups of genes examined computationally. Results We find that groups of genes that share a function or belong to a common pathway share upstream motifs. Different motifs are conserved upstream of different groups of genes. Comparative real-time PCR studies show co-expression of genes within each group (in sub-sets during the life cycle of the parasite, suggesting co-regulation of these genes may be driven by the use of conserved upstream motifs. Conclusion This is one of the first attempts to characterize cis-regulatory elements in the absence of any previously characterized elements and with very limited expression data (seven genes only. Using de novo pattern finding algorithms, we have identified specific DNA motifs that are conserved upstream of genes belonging to the same metabolic pathway or gene family. We have demonstrated the co-expression of these genes (often in subsets using comparative real-time-PCR experiments thus establishing evidence for these conserved motifs as putative cis-regulatory elements. Given the lack of prior information concerning expression patterns and organization of promoters in C. parvum we

  8. Patterned Arrays of Functional Lateral Heterostructures via Sequential Template-Directed Printing.

    Science.gov (United States)

    Li, Yifan; Su, Meng; Li, Zheng; Huang, Zhandong; Li, Fengyu; Pan, Qi; Ren, Wanjie; Hu, Xiaotian; Song, Yanlin

    2018-04-30

    The precise integration of microscale dots and lines with controllable interfacing connections is highly important for the fabrication of functional devices. To date, the solution-processible methods are used to fabricate the heterogeneous micropatterns for different materials. However, for increasingly miniaturized and multifunctional devices, it is extremely challenging to engineer the uncertain kinetics of a solution on the microstructures surfaces, resulting in uncontrollable interface connections and poor device performance. Here, a sequential template-directed printing process is demonstrated for the fabrication of arrayed microdots connected by microwires through the regulation of the Rayleigh-Taylor instability of material solution or suspension. Flexibility in the control of fluidic behaviors can realize precise interface connection between the micropatterns, including the microwires traversing, overlapping or connecting the microdots. Moreover, various morphologies such as circular, rhombic, or star-shaped microdots as well as straight, broken or curved microwires can be achieved. The lateral heterostructure printed with two different quantum dots displays bright dichromatic photoluminescence. The ammonia gas sensor printed by polyaniline and silver nanoparticles exhibits a rapid response time. This strategy can construct heterostructures in a facile manner by eliminating the uncertainty of the multimaterials interface connection, which will be promising for the development of novel lateral functional devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Functional Improvement after Photothrombotic Stroke in Rats Is Associated with Different Patterns of Dendritic Plasticity after G-CSF Treatment and G-CSF Treatment Combined with Concomitant or Sequential Constraint-Induced Movement Therapy.

    Directory of Open Access Journals (Sweden)

    Katrin Frauenknecht

    Full Text Available We have previously shown that granulocyte-colony stimulating factor (G-CSF treatment alone, or in combination with constraint movement therapy (CIMT either sequentially or concomitantly, results in significantly improved sensorimotor recovery after photothrombotic stroke in rats in comparison to untreated control animals. CIMT alone did not result in any significant differences compared to the control group (Diederich et al., Stroke, 2012;43:185-192. Using a subset of rat brains from this former experiment the present study was designed to evaluate whether dendritic plasticity would parallel improved functional outcomes. Five treatment groups were analyzed (n = 6 each (i ischemic control (saline; (ii CIMT (CIMT between post-stroke days 2 and 11; (iii G-CSF (10 μg/kg G-CSF daily between post-stroke days 2 and 11; (iv combined concurrent group (CIMT plus G-CSF and (v combined sequential group (CIMT between post-stroke days 2 and 11; 10 μg/kg G-CSF daily between post-stroke days 12 and 21, respectively. After impregnation of rat brains with a modified Golgi-Cox protocol layer V pyramidal neurons in the peri-infarct cortex as well as the corresponding contralateral cortex were analyzed. Surprisingly, animals with a similar degree of behavioral recovery exhibited quite different patterns of dendritic plasticity in both peri-lesional and contralesional areas. The cause for these patterns is not easily to explain but puts the simple assumption that increased dendritic complexity after stroke necessarily results in increased functional outcome into perspective.

  10. ICRPfinder: a fast pattern design algorithm for coding sequences and its application in finding potential restriction enzyme recognition sites

    Directory of Open Access Journals (Sweden)

    Stafford Phillip

    2009-09-01

    Full Text Available Abstract Background Restriction enzymes can produce easily definable segments from DNA sequences by using a variety of cut patterns. There are, however, no software tools that can aid in gene building -- that is, modifying wild-type DNA sequences to express the same wild-type amino acid sequences but with enhanced codons, specific cut sites, unique post-translational modifications, and other engineered-in components for recombinant applications. A fast DNA pattern design algorithm, ICRPfinder, is provided in this paper and applied to find or create potential recognition sites in target coding sequences. Results ICRPfinder is applied to find or create restriction enzyme recognition sites by introducing silent mutations. The algorithm is shown capable of mapping existing cut-sites but importantly it also can generate specified new unique cut-sites within a specified region that are guaranteed not to be present elsewhere in the DNA sequence. Conclusion ICRPfinder is a powerful tool for finding or creating specific DNA patterns in a given target coding sequence. ICRPfinder finds or creates patterns, which can include restriction enzyme recognition sites, without changing the translated protein sequence. ICRPfinder is a browser-based JavaScript application and it can run on any platform, in on-line or off-line mode.

  11. Radial basis function neural networks with sequential learning MRAN and its applications

    CERN Document Server

    Sundararajan, N; Wei Lu Ying

    1999-01-01

    This book presents in detail the newly developed sequential learning algorithm for radial basis function neural networks, which realizes a minimal network. This algorithm, created by the authors, is referred to as Minimal Resource Allocation Networks (MRAN). The book describes the application of MRAN in different areas, including pattern recognition, time series prediction, system identification, control, communication and signal processing. Benchmark problems from these areas have been studied, and MRAN is compared with other algorithms. In order to make the book self-contained, a review of t

  12. MUSCLE OR MOTIVATION? A STOP SIGNAL STUDY ON THE EFFECTS OF SEQUENTIAL COGNITIVE CONTROL

    Directory of Open Access Journals (Sweden)

    Hilde M. Huizenga

    2012-05-01

    Full Text Available Performance in cognitive control tasks deteriorates when these tasks are performed together with other tasks that also require cognitive control, that is, if simultaneous cognitive control is required. Surprisingly, this decrease in performance is also observed if tasks are preceded by other cognitive control tasks, that is, if sequential cognitive control is required. The common explanation for the latter finding is that previous acts of cognitive control deplete a common resource, just like a muscle becomes fatigued after repeated use. An alternative explanation however has also been put forward, namely that repeated acts of cognitive control reduce the motivation to match allocated resources to required resources. In this paper we formalize these two accounts, the muscle and the motivation account, and show that they yield differential predictions on the interaction between simultaneous and sequential cognitive control. Such an interaction is not predicted by the muscle account, whereas it is predicted by the motivation account.These predictions were tested in a paradigm where participants had to perform a series of stop-signal tasks, these tasks varied both in their demands on simultaneous control and in their demands on sequential control. This paradigm, combined with a multilevel analysis, offered the possibility to test the differential predictions directly. Results of two studies indicate that an interaction between simultaneous and sequential cognitive control is present. Therefore it is concluded that effects of sequential cognitive control are best explained by the motivation account.

  13. Characterizing the structure and content of nurse handoffs: A Sequential Conversational Analysis approach.

    Science.gov (United States)

    Abraham, Joanna; Kannampallil, Thomas; Brenner, Corinne; Lopez, Karen D; Almoosa, Khalid F; Patel, Bela; Patel, Vimla L

    2016-02-01

    Effective communication during nurse handoffs is instrumental in ensuring safe and quality patient care. Much of the prior research on nurse handoffs has utilized retrospective methods such as interviews, surveys and questionnaires. While extremely useful, an in-depth understanding of the structure and content of conversations, and the inherent relationships within the content is paramount to designing effective nurse handoff interventions. In this paper, we present a methodological framework-Sequential Conversational Analysis (SCA)-a mixed-method approach that integrates qualitative conversational analysis with quantitative sequential pattern analysis. We describe the SCA approach and provide a detailed example as a proof of concept of its use for the analysis of nurse handoff communication in a medical intensive care unit. This novel approach allows us to characterize the conversational structure, clinical content, disruptions in the conversation, and the inherently phasic nature of nurse handoff communication. The characterization of communication patterns highlights the relationships underlying the verbal content of nurse handoffs with specific emphasis on: the interactive nature of conversation, relevance of role-based (incoming, outgoing) communication requirements, clinical content focus on critical patient-related events, and discussion of pending patient management tasks. We also discuss the applicability of the SCA approach as a method for providing in-depth understanding of the dynamics of communication in other settings and domains. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Discrimination between sequential and simultaneous virtual channels with electrical hearing.

    Science.gov (United States)

    Landsberger, David; Galvin, John J

    2011-09-01

    In cochlear implants (CIs), simultaneous or sequential stimulation of adjacent electrodes can produce intermediate pitch percepts between those of the component electrodes. However, it is unclear whether simultaneous and sequential virtual channels (VCs) can be discriminated. In this study, CI users were asked to discriminate simultaneous and sequential VCs; discrimination was measured for monopolar (MP) and bipolar + 1 stimulation (BP + 1), i.e., relatively broad and focused stimulation modes. For sequential VCs, the interpulse interval (IPI) varied between 0.0 and 1.8 ms. All stimuli were presented at comfortably loud, loudness-balanced levels at a 250 pulse per second per electrode (ppse) stimulation rate. On average, CI subjects were able to reliably discriminate between sequential and simultaneous VCs. While there was no significant effect of IPI or stimulation mode on VC discrimination, some subjects exhibited better VC discrimination with BP + 1 stimulation. Subjects' discrimination between sequential and simultaneous VCs was correlated with electrode discrimination, suggesting that spatial selectivity may influence perception of sequential VCs. To maintain equal loudness, sequential VC amplitudes were nearly double those of simultaneous VCs, presumably resulting in a broader spread of excitation. These results suggest that perceptual differences between simultaneous and sequential VCs might be explained by differences in the spread of excitation. © 2011 Acoustical Society of America

  15. Sequential versus simultaneous market delineation

    DEFF Research Database (Denmark)

    Haldrup, Niels; Møllgaard, Peter; Kastberg Nielsen, Claus

    2005-01-01

    and geographical markets. Using a unique data setfor prices of Norwegian and Scottish salmon, we propose a methodologyfor simultaneous market delineation and we demonstrate that comparedto a sequential approach conclusions will be reversed.JEL: C3, K21, L41, Q22Keywords: Relevant market, econometric delineation......Delineation of the relevant market forms a pivotal part of most antitrustcases. The standard approach is sequential. First the product marketis delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographicaldimension...

  16. Eyewitness accuracy rates in sequential and simultaneous lineup presentations: a meta-analytic comparison.

    Science.gov (United States)

    Steblay, N; Dysart, J; Fulero, S; Lindsay, R C

    2001-10-01

    Most police lineups use a simultaneous presentation technique in which eyewitnesses view all lineup members at the same time. Lindsay and Wells (R. C. L. Lindsay & G. L. Wells, 1985) devised an alternative procedure, the sequential lineup, in which witnesses view one lineup member at a time and decide whether or not that person is the perpetrator prior to viewing the next lineup member. The present work uses the technique of meta-analysis to compare the accuracy rates of these presentation styles. Twenty-three papers were located (9 published and 14 unpublished), providing 30 tests of the hypothesis and including 4,145 participants. Results showed that identification of perpetrators from target-present lineups occurs at a higher rate from simultaneous than from sequential lineups. However, this difference largely disappears when moderator variables approximating real world conditions are considered. Also, correct rejection rates were significantly higher for sequential than simultaneous lineups and this difference is maintained or increased by greater approximation to real world conditions. Implications of these findings are discussed.

  17. Comparative efficacy of simultaneous versus sequential multiple health behavior change interventions among adults: A systematic review of randomised trials.

    Science.gov (United States)

    James, Erica; Freund, Megan; Booth, Angela; Duncan, Mitch J; Johnson, Natalie; Short, Camille E; Wolfenden, Luke; Stacey, Fiona G; Kay-Lambkin, Frances; Vandelanotte, Corneel

    2016-08-01

    Growing evidence points to the benefits of addressing multiple health behaviors rather than single behaviors. This review evaluates the relative effectiveness of simultaneous and sequentially delivered multiple health behavior change (MHBC) interventions. Secondary aims were to identify: a) the most effective spacing of sequentially delivered components; b) differences in efficacy of MHBC interventions for adoption/cessation behaviors and lifestyle/addictive behaviors, and; c) differences in trial retention between simultaneously and sequentially delivered interventions. MHBC intervention trials published up to October 2015 were identified through a systematic search. Eligible trials were randomised controlled trials that directly compared simultaneous and sequential delivery of a MHBC intervention. A narrative synthesis was undertaken. Six trials met the inclusion criteria and across these trials the behaviors targeted were smoking, diet, physical activity, and alcohol consumption. Three trials reported a difference in intervention effect between a sequential and simultaneous approach in at least one behavioral outcome. Of these, two trials favoured a sequential approach on smoking. One trial favoured a simultaneous approach on fat intake. There was no difference in retention between sequential and simultaneous approaches. There is limited evidence regarding the relative effectiveness of sequential and simultaneous approaches. Given only three of the six trials observed a difference in intervention effectiveness for one health behavior outcome, and the relatively consistent finding that the sequential and simultaneous approaches were more effective than a usual/minimal care control condition, it appears that both approaches should be considered equally efficacious. PROSPERO registration number: CRD42015027876. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Influence of Sequential vs. Simultaneous Dual-Task Exercise Training on Cognitive Function in Older Adults.

    Science.gov (United States)

    Tait, Jamie L; Duckham, Rachel L; Milte, Catherine M; Main, Luana C; Daly, Robin M

    2017-01-01

    Emerging research indicates that exercise combined with cognitive training may improve cognitive function in older adults. Typically these programs have incorporated sequential training, where exercise and cognitive training are undertaken separately. However, simultaneous or dual-task training, where cognitive and/or motor training are performed simultaneously with exercise, may offer greater benefits. This review summary provides an overview of the effects of combined simultaneous vs. sequential training on cognitive function in older adults. Based on the available evidence, there are inconsistent findings with regard to the cognitive benefits of sequential training in comparison to cognitive or exercise training alone. In contrast, simultaneous training interventions, particularly multimodal exercise programs in combination with secondary tasks regulated by sensory cues, have significantly improved cognition in both healthy older and clinical populations. However, further research is needed to determine the optimal characteristics of a successful simultaneous training program for optimizing cognitive function in older people.

  19. Parameter sampling capabilities of sequential and simultaneous data assimilation: I. Analytical comparison

    International Nuclear Information System (INIS)

    Fossum, Kristian; Mannseth, Trond

    2014-01-01

    We assess the parameter sampling capabilities of some Bayesian, ensemble-based, joint state-parameter (JS) estimation methods. The forward model is assumed to be non-chaotic and have nonlinear components, and the emphasis is on results obtained for the parameters in the state-parameter vector. A variety of approximate sampling methods exist, and a number of numerical comparisons between such methods have been performed. Often, more than one of the defining characteristics vary from one method to another, so it can be difficult to point out which characteristic of the more successful method in such a comparison was decisive. In this study, we single out one defining characteristic for comparison; whether or not data are assimilated sequentially or simultaneously. The current paper is concerned with analytical investigations into this issue. We carefully select one sequential and one simultaneous JS method for the comparison. We also design a corresponding pair of pure parameter estimation methods, and we show how the JS methods and the parameter estimation methods are pairwise related. It is shown that the sequential and the simultaneous parameter estimation methods are equivalent for one particular combination of observations with different degrees of nonlinearity. Strong indications are presented for why one may expect the sequential parameter estimation method to outperform the simultaneous parameter estimation method for all other combinations of observations. Finally, the conditions for when similar relations can be expected to hold between the corresponding JS methods are discussed. A companion paper, part II (Fossum and Mannseth 2014 Inverse Problems 30 114003), is concerned with statistical analysis of results from a range of numerical experiments involving sequential and simultaneous JS estimation, where the design of the numerical investigation is motivated by our findings in the current paper. (paper)

  20. Group-sequential analysis may allow for early trial termination

    DEFF Research Database (Denmark)

    Gerke, Oke; Vilstrup, Mie H; Halekoh, Ulrich

    2017-01-01

    BACKGROUND: Group-sequential testing is widely used in pivotal therapeutic, but rarely in diagnostic research, although it may save studies, time, and costs. The purpose of this paper was to demonstrate a group-sequential analysis strategy in an intra-observer study on quantitative FDG-PET/CT mea......BACKGROUND: Group-sequential testing is widely used in pivotal therapeutic, but rarely in diagnostic research, although it may save studies, time, and costs. The purpose of this paper was to demonstrate a group-sequential analysis strategy in an intra-observer study on quantitative FDG...

  1. Sequential logic analysis and synthesis

    CERN Document Server

    Cavanagh, Joseph

    2007-01-01

    Until now, there was no single resource for actual digital system design. Using both basic and advanced concepts, Sequential Logic: Analysis and Synthesis offers a thorough exposition of the analysis and synthesis of both synchronous and asynchronous sequential machines. With 25 years of experience in designing computing equipment, the author stresses the practical design of state machines. He clearly delineates each step of the structured and rigorous design principles that can be applied to practical applications. The book begins by reviewing the analysis of combinatorial logic and Boolean a

  2. Sequential and selective localized optical heating in water via on-chip dielectric nanopatterning.

    Science.gov (United States)

    Morsy, Ahmed M; Biswas, Roshni; Povinelli, Michelle L

    2017-07-24

    We study the use of nanopatterned silicon membranes to obtain optically-induced heating in water. We show that by varying the detuning between an absorptive optical resonance of the patterned membrane and an illumination laser, both the magnitude and response time of the temperature rise can be controlled. This allows for either sequential or selective heating of different patterned areas on chip. We obtain a steady-state temperature of approximately 100 °C for a 805.5nm CW laser power density of 66 µW/μm 2 and observe microbubble formation. The ability to spatially and temporally control temperature on the microscale should enable the study of heat-induced effects in a variety of chemical and biological lab-on-chip applications.

  3. Modified sequential extraction for biochar and petroleum coke: Metal release potential and its environmental implications.

    Science.gov (United States)

    von Gunten, Konstantin; Alam, Md Samrat; Hubmann, Magdalena; Ok, Yong Sik; Konhauser, Kurt O; Alessi, Daniel S

    2017-07-01

    A modified Community Bureau of Reference (CBR) sequential extraction method was tested to assess the composition of untreated pyrogenic carbon (biochar) and oil sands petroleum coke. Wood biochar samples were found to contain lower concentrations of metals, but had higher fractions of easily mobilized alkaline earth and transition metals. Sewage sludge biochar was determined to be less recalcitrant and had higher total metal concentrations, with most of the metals found in the more resilient extraction fractions (oxidizable, residual). Petroleum coke was the most stable material, with a similar metal distribution pattern as the sewage sludge biochar. The applied sequential extraction method represents a suitable technique to recover metals from these materials, and is a valuable tool in understanding the metal retaining and leaching capability of various biochar types and carbonaceous petroleum coke samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. In-situ sequential laser transfer and laser reduction of graphene oxide films

    Science.gov (United States)

    Papazoglou, S.; Petridis, C.; Kymakis, E.; Kennou, S.; Raptis, Y. S.; Chatzandroulis, S.; Zergioti, I.

    2018-04-01

    Achieving high quality transfer of graphene on selected substrates is a priority in device fabrication, especially where drop-on-demand applications are involved. In this work, we report an in-situ, fast, simple, and one step process that resulted in the reduction, transfer, and fabrication of reduced graphene oxide-based humidity sensors, using picosecond laser pulses. By tuning the laser illumination parameters, we managed to implement the sequential printing and reduction of graphene oxide flakes. The overall process lasted only a few seconds compared to a few hours that our group has previously published. DC current measurements, X-Ray Photoelectron Spectroscopy, X-Ray Diffraction, and Raman Spectroscopy were employed in order to assess the efficiency of our approach. To demonstrate the applicability and the potential of the technique, laser printed reduced graphene oxide humidity sensors with a limit of detection of 1700 ppm are presented. The results demonstrated in this work provide a selective, rapid, and low-cost approach for sequential transfer and photochemical reduction of graphene oxide micro-patterns onto various substrates for flexible electronics and sensor applications.

  5. The biological effects of quadripolar radiofrequency sequential application: a human experimental study.

    Science.gov (United States)

    Nicoletti, Giovanni; Cornaglia, Antonia Icaro; Faga, Angela; Scevola, Silvia

    2014-10-01

    An experimental study was conducted to assess the effectiveness and safety of an innovative quadripolar variable electrode configuration radiofrequency device with objective measurements in an ex vivo and in vivo human experimental model. Nonablative radiofrequency applications are well-established anti-ageing procedures for cosmetic skin tightening. The study was performed in two steps: ex vivo and in vivo assessments. In the ex vivo assessments the radiofrequency applications were performed on human full-thickness skin and subcutaneous tissue specimens harvested during surgery for body contouring. In the in vivo assessments the applications were performed on two volunteer patients scheduled for body contouring surgery at the end of the study. The assessment methods were: clinical examination and medical photography, temperature measurement with thermal imaging scan, and light microscopy histological examination. The ex vivo assessments allowed for identification of the effective safety range for human application. The in vivo assessments allowed for demonstration of the biological effects of sequential radiofrequency applications. After a course of radiofrequency applications, the collagen fibers underwent an immediate heat-induced rearrangement and were partially denaturated and progressively metabolized by the macrophages. An overall thickening and spatial rearrangement was appreciated both in the collagen and elastic fibers, the latter displaying a juvenile reticular pattern. A late onset in the macrophage activation after sequential radiofrequency applications was appreciated. Our data confirm the effectiveness of sequential radiofrequency applications in obtaining attenuation of the skin wrinkles by an overall skin tightening.

  6. Full-Color LCD Microdisplay System Based on OLED Backlight Unit and Field-Sequential Color Driving Method

    Directory of Open Access Journals (Sweden)

    Sungho Woo

    2011-01-01

    Full Text Available We developed a single-panel LCD microdisplay system using a field-sequential color (FSC driving method and an organic light-emitting diode (OLED as a backlight unit (BLU. The 0.76′′ OLED BLU with red, green, and blue (RGB colors was fabricated by a conventional UV photolithography patterning process and by vacuum deposition of small molecule organic layers. The field-sequential driving frequency was set to 255 Hz to allow each of the RGB colors to be generated without color mixing at the given display frame rate. A prototype FSC LCD microdisplay system consisting of a 0.7′′ LCD microdisplay panel and the 0.76′′ OLED BLU successfully exhibited color display and moving picture images using the FSC driving method.

  7. Structural Consistency, Consistency, and Sequential Rationality.

    OpenAIRE

    Kreps, David M; Ramey, Garey

    1987-01-01

    Sequential equilibria comprise consistent beliefs and a sequentially ra tional strategy profile. Consistent beliefs are limits of Bayes ratio nal beliefs for sequences of strategies that approach the equilibrium strategy. Beliefs are structurally consistent if they are rationaliz ed by some single conjecture concerning opponents' strategies. Consis tent beliefs are not necessarily structurally consistent, notwithstan ding a claim by Kreps and Robert Wilson (1982). Moreover, the spirit of stru...

  8. Pulmonary alveolar proteinosis versus exogenous lipoid pneumonia showing crazy-paving pattern: Comparison of their clinical features and high-resolution CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hei Kyung; Park, Chang Min; Goo, Jin Mo; Lee, Hyun Ju (Dept. of Radiology, Seoul National Univ. College of Medicine, and Inst. of Radiation Medicine, Seoul National Univ. Medical Research Center, Seoul (Korea)), e-mail: cmpark@radiol.snu.ac.kr

    2010-05-15

    Background: Although pulmonary alveolar proteinosis (PAP) and exogenous lipoid pneumonia (ELP) require different treatment strategies, both manifest as a crazy-paving pattern on CT and often have similar clinical manifestations and radiologic features. Purpose: To investigate the clinical features and high-resolution computed tomography (HRCT) findings of PAP and ELP showing the crazy-paving pattern. Material and Methods: The clinical features and HRCT findings of eight patients with pathologically proven PAP and six patients with pathologically proven ELP showing the crazy-paving pattern were retrospectively evaluated. Two radiologists analyzed the HRCT findings of PAP and ELP in consensus in terms of the presence, severity, and extent of illdefined centrilobular nodules, consolidations, ground-glass opacities (GGOs), reticulations, and the crazy-paving pattern. Results: With respect to the clinical features of these two diseases, all patients with ELP were retrospectively found to have a history of oil ingestion. In terms of the HRCT findings, ill-defined centrilobular nodules were seen in five of six patients (83%) with ELP, whereas they were not present in any patient with PAP (P=0.003). Consolidation was also more frequently present in patients with ELP (83%) than in those with PAP (11%), which was statistically different (P=0.0265). In terms of the severity and extent, the crazy-paving pattern and reticulations on HRCT were significantly more extensive and severe in patients with PAP than in those with ELP. Conclusion: PAP and ELP with the crazy-paving pattern have several distinctive characteristics with respect to their HRCT findings as well as history of oil ingestion, and can therefore be distinguished from one another

  9. Introducing sequential managed aquifer recharge technology (SMART) - From laboratory to full-scale application.

    Science.gov (United States)

    Regnery, Julia; Wing, Alexandre D; Kautz, Jessica; Drewes, Jörg E

    2016-07-01

    Previous lab-scale studies demonstrated that stimulating the indigenous soil microbial community of groundwater recharge systems by manipulating the availability of biodegradable organic carbon (BDOC) and establishing sequential redox conditions in the subsurface resulted in enhanced removal of compounds with redox-dependent removal behavior such as trace organic chemicals. The aim of this study is to advance this concept from laboratory to full-scale application by introducing sequential managed aquifer recharge technology (SMART). To validate the concept of SMART, a full-scale managed aquifer recharge (MAR) facility in Colorado was studied for three years that featured the proposed sequential configuration: A short riverbank filtration passage followed by subsequent re-aeration and artificial recharge and recovery. Our findings demonstrate that sequential subsurface treatment zones characterized by carbon-rich (>3 mg/L BDOC) to carbon-depleted (≤1 mg/L BDOC) and predominant oxic redox conditions can be established at full-scale MAR facilities adopting the SMART concept. The sequential configuration resulted in substantially improved trace organic chemical removal (i.e. higher biodegradation rate coefficients) for moderately biodegradable compounds compared to conventional MAR systems with extended travel times in an anoxic aquifer. Furthermore, sorption batch experiments with clay materials dispersed in the subsurface implied that sorptive processes might also play a role in the attenuation and retardation of chlorinated flame retardants during MAR. Hence, understanding key factors controlling trace organic chemical removal performance during SMART allows for systems to be engineered for optimal efficiency, resulting in improved removal of constituents at shorter subsurface travel times and a potentially reduced physical footprint of MAR installations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Generalized infimum and sequential product of quantum effects

    International Nuclear Information System (INIS)

    Li Yuan; Sun Xiuhong; Chen Zhengli

    2007-01-01

    The quantum effects for a physical system can be described by the set E(H) of positive operators on a complex Hilbert space H that are bounded above by the identity operator I. For A, B(set-membership sign)E(H), the operation of sequential product A(convolution sign)B=A 1/2 BA 1/2 was proposed as a model for sequential quantum measurements. A nice investigation of properties of the sequential product has been carried over [Gudder, S. and Nagy, G., 'Sequential quantum measurements', J. Math. Phys. 42, 5212 (2001)]. In this note, we extend some results of this reference. In particular, a gap in the proof of Theorem 3.2 in this reference is overcome. In addition, some properties of generalized infimum A sqcap B are studied

  11. Pattern Discovery in Time-Ordered Data; TOPICAL

    International Nuclear Information System (INIS)

    CONRAD, GREGORY N.; BRITANIK, JOHN M.; DELAND, SHARON M.; JENKIN, CHRISTINA L.

    2002-01-01

    This report describes the results of a Laboratory-Directed Research and Development project on techniques for pattern discovery in discrete event time series data. In this project, we explored two different aspects of the pattern matching/discovery problem. The first aspect studied was the use of Dynamic Time Warping for pattern matching in continuous data. In essence, DTW is a technique for aligning time series along the time axis to optimize the similarity measure. The second aspect studied was techniques for discovering patterns in discrete event data. We developed a pattern discovery tool based on adaptations of the A-priori and GSP (Generalized Sequential Pattern mining) algorithms. We then used the tool on three different application areas-unattended monitoring system data from a storage magazine, computer network intrusion detection, and analysis of robot training data

  12. Group-sequential analysis may allow for early trial termination

    DEFF Research Database (Denmark)

    Gerke, Oke; Vilstrup, Mie H; Halekoh, Ulrich

    2017-01-01

    BACKGROUND: Group-sequential testing is widely used in pivotal therapeutic, but rarely in diagnostic research, although it may save studies, time, and costs. The purpose of this paper was to demonstrate a group-sequential analysis strategy in an intra-observer study on quantitative FDG-PET/CT mea......BACKGROUND: Group-sequential testing is widely used in pivotal therapeutic, but rarely in diagnostic research, although it may save studies, time, and costs. The purpose of this paper was to demonstrate a group-sequential analysis strategy in an intra-observer study on quantitative FDG...... assumed to be normally distributed, and sequential one-sided hypothesis tests on the population standard deviation of the differences against a hypothesised value of 1.5 were performed, employing an alpha spending function. The fixed-sample analysis (N = 45) was compared with the group-sequential analysis...... strategies comprising one (at N = 23), two (at N = 15, 30), or three interim analyses (at N = 11, 23, 34), respectively, which were defined post hoc. RESULTS: When performing interim analyses with one third and two thirds of patients, sufficient agreement could be concluded after the first interim analysis...

  13. Pulmonary mucormycosis. Serial morphologic changes on computed tomography correlate with clinical and pathologic findings

    International Nuclear Information System (INIS)

    Nam, Bo Da; Kim, Tae Jung; Lee, Kyung Soo; Kim, Tae Sung; Chung, Myung Jin; Han, Joungho

    2018-01-01

    To evaluate serial computed tomography (CT) findings of pulmonary mucormycosis correlated with peripheral blood absolute neutrophil count (ANC). Between February 1997 and June 2016, 20 immunocompromised patients (10 males, 10 females; mean age, 48.9 years) were histopathologically diagnosed as pulmonary mucormycosis. On initial (n=20) and follow-up (n=15) CT scans, the patterns of lung abnormalities and their changing features on follow-up scans were evaluated, and the pattern changes were correlated with ANC changes. All patients were immunocompromised. On initial CT scans, nodule (≤3cm)/mass (>3cm) or consolidation with surrounding ground-glass opacity halo (18/20, 90%) was the most common pattern. On follow-up CT, morphologic changes (13/15, 87%) could be seen and they included reversed halo (RH) sign, central necrosis, and air-crescent sign. Although all cases did not demonstrate the regular morphologic changes at the same timeline, various combinations of pattern change could be seen in all patients. Sequential morphologic changes were related with recovering of ANC in 13 of 15 patients. Pulmonary mucormycosis most frequently presents as consolidation or nodule/mass with halo sign at CT. Morphologic changes into RH sign, central necrotic cavity or air-crescent sign occur with treatment and recovery of ANC. (orig.)

  14. Pulmonary mucormycosis. Serial morphologic changes on computed tomography correlate with clinical and pathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Bo Da; Kim, Tae Jung; Lee, Kyung Soo; Kim, Tae Sung; Chung, Myung Jin [Samsung Medical Centre, Sungkyunkwan University School of Medicine, Department of Radiology and Centre for Imaging Science, Seoul (Korea, Republic of); Han, Joungho [Samsung Medical Centre, Sungkyunkwan University School of Medicine, Department of Pathology, Seoul (Korea, Republic of)

    2018-02-15

    To evaluate serial computed tomography (CT) findings of pulmonary mucormycosis correlated with peripheral blood absolute neutrophil count (ANC). Between February 1997 and June 2016, 20 immunocompromised patients (10 males, 10 females; mean age, 48.9 years) were histopathologically diagnosed as pulmonary mucormycosis. On initial (n=20) and follow-up (n=15) CT scans, the patterns of lung abnormalities and their changing features on follow-up scans were evaluated, and the pattern changes were correlated with ANC changes. All patients were immunocompromised. On initial CT scans, nodule (≤3cm)/mass (>3cm) or consolidation with surrounding ground-glass opacity halo (18/20, 90%) was the most common pattern. On follow-up CT, morphologic changes (13/15, 87%) could be seen and they included reversed halo (RH) sign, central necrosis, and air-crescent sign. Although all cases did not demonstrate the regular morphologic changes at the same timeline, various combinations of pattern change could be seen in all patients. Sequential morphologic changes were related with recovering of ANC in 13 of 15 patients. Pulmonary mucormycosis most frequently presents as consolidation or nodule/mass with halo sign at CT. Morphologic changes into RH sign, central necrotic cavity or air-crescent sign occur with treatment and recovery of ANC. (orig.)

  15. Comparison of ablation centration after bilateral sequential versus simultaneous LASIK.

    Science.gov (United States)

    Lin, Jane-Ming; Tsai, Yi-Yu

    2005-01-01

    To compare ablation centration after bilateral sequential and simultaneous myopic LASIK. A retrospective randomized case series was performed of 670 eyes of 335 consecutive patients who had undergone either bilateral sequential (group 1) or simultaneous (group 2) myopic LASIK between July 2000 and July 2001 at the China Medical University Hospital, Taichung, Taiwan. The ablation centrations of the first and second eyes in the two groups were compared 3 months postoperatively. Of 670 eyes, 274 eyes (137 patients) comprised the sequential group and 396 eyes (198 patients) comprised the simultaneous group. Three months post-operatively, 220 eyes of 110 patients (80%) in the sequential group and 236 eyes of 118 patients (60%) in the simultaneous group provided topographic data for centration analysis. For the first eyes, mean decentration was 0.39 +/- 0.26 mm in the sequential group and 0.41 +/- 0.19 mm in the simultaneous group (P = .30). For the second eyes, mean decentration was 0.28 +/- 0.23 mm in the sequential group and 0.30 +/- 0.21 mm in the simultaneous group (P = .36). Decentration in the second eyes significantly improved in both groups (group 1, P = .02; group 2, P sequential group and 0.32 +/- 0.18 mm in the simultaneous group (P = .33). The difference of ablation center angles between the first and second eyes was 43.2 sequential group and 45.1 +/- 50.8 degrees in the simultaneous group (P = .42). Simultaneous bilateral LASIK is comparable to sequential surgery in ablation centration.

  16. Sequential Therapy of Community-Acquired Pneumonia in Children

    Directory of Open Access Journals (Sweden)

    I.A. Karimdzhanov

    2014-04-01

    Full Text Available Aim of the study — to examine the effectiveness of sequential therapy of injectable and oral forms cephalosporins of II generation, cefuroxime sodium and cefprozil, in children with acute community-acquired pneumonia. We examined 53 child patients aged 6 months — 14 years with acute community-acquired pneumonia. Patients were divided into 2 groups: 1st group — 26 patients who treated with cefuroxime sodium intramuscularly, and 2nd — 27 patients who treated with cefuroxime sodium in first 3 days and then from the 4th day — with cefprozil suspension orally. Both groups of patients were comparable by forms and course of pneumonia. In the clinic to all patients were conducted conventional clinical and laboratory investigations. Complex therapy was not different in both groups. Efficacy of treatment was assessed in dynamics. When comparing the effectiveness of two antibiotic regimens (cefuroxime sodium parenterally and sequential regimen with replacement by cefprozil orally there were no differences in the dynamics of clinical course, laboratory and radiological data. Finding of the conducted investigations before treatment showed that majority of patients had clinical and radiological evidence of pneumonia: fever, cough, shortness of breath, tachycardia, physical and radiological changes in the lungs. Evaluation of treatment efficacy showed that by the end of treatment in both groups of patients there was a positive clinical and radiological dynamics of the disease, the body temperature returned to normal, symptoms of intoxication, physical changes in the lungs disappeared, focal and infiltrative changes disappeared completely. Thus, sequential therapy with cephalosporins of II generation, cefuroxime and cefprozil, in the treatment of acute community-acquired pneumonia in children is a quite effective and safe method with good tolerability and no side effects.

  17. A Survey of Multi-Objective Sequential Decision-Making

    NARCIS (Netherlands)

    Roijers, D.M.; Vamplew, P.; Whiteson, S.; Dazeley, R.

    2013-01-01

    Sequential decision-making problems with multiple objectives arise naturally in practice and pose unique challenges for research in decision-theoretic planning and learning, which has largely focused on single-objective settings. This article surveys algorithms designed for sequential

  18. Sequential lineups: shift in criterion or decision strategy?

    Science.gov (United States)

    Gronlund, Scott D

    2004-04-01

    R. C. L. Lindsay and G. L. Wells (1985) argued that a sequential lineup enhanced discriminability because it elicited use of an absolute decision strategy. E. B. Ebbesen and H. D. Flowe (2002) argued that a sequential lineup led witnesses to adopt a more conservative response criterion, thereby affecting bias, not discriminability. Height was encoded as absolute (e.g., 6 ft [1.83 m] tall) or relative (e.g., taller than). If a sequential lineup elicited an absolute decision strategy, the principle of transfer-appropriate processing predicted that performance should be best when height was encoded absolutely. Conversely, if a simultaneous lineup elicited a relative decision strategy, performance should be best when height was encoded relatively. The predicted interaction was observed, providing direct evidence for the decision strategies explanation of what happens when witnesses view a sequential lineup.

  19. MRI findings and spreading patterns of necrotizing external otitis: Is a poor outcome predictable?

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, B.J. [Department of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, M.H. [Department of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of) and Clinical Research Institute, Seoul National University Hospital, Seoul (Korea, Republic of) and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of)]. E-mail: hanmh@radcom.snu.ac.kr; Oh, S.H. [Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Song, J.J. [Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chang, K.-H. [Department of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Clinical Research Institute, Seoul National University Hospital, Seoul (Korea, Republic of); Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of)

    2006-06-15

    AIM: To evaluate spreading patterns of necrotizing external otitis (NEO) by magnetic resonance imaging (MRI) and to identify spreading patterns related to a poor outcome. MATERIALS AND METHODS: Fourteen patients with NEO were divided into good and poor outcome groups according to their final clinical outcomes. Initial MRI images were retrospectively reviewed for regional abnormalities, and follow-up MRI images were reviewed for ICA flow void abnormality and for the following five spreading patterns: medial, crossed, anterior, intracranial, and combined. The frequencies of the abnormal flow void or spreading patterns were compared between the good and poor response groups. RESULTS: Seven (50%) and seven (50%) patients were respectively allocated to the good and poor outcome groups. Retrocondylar fat infiltration was the most commonest finding on initial MRI images (93%). The frequencies of the abnormal flow void and spreading patterns in the good and poor groups, respectively, were: abnormal flow void, 0 and four (57%); anterior, two (29%) and three (43%); medial, six (86%) and seven (100%); crossed, six (86%) and seven (100%); intracranial middle cranial fossa, one (14%) and four (57%); intracranial posterior cranial fossa, four (57%) and six (86%); intracranial foramen magnum, one (14%) and six (86%). CONCLUSIONS: NEO almost always involves the retrocondylar fat and spreads via various pathways to extracranial or intracranial spaces. The presence of an abnormal flow void and intracranial dural enhancement, particularly in the middle cranial fossa and foramen magnum, may indicate a poor prognosis.

  20. MRI findings and spreading patterns of necrotizing external otitis: Is a poor outcome predictable?

    International Nuclear Information System (INIS)

    Kwon, B.J.; Han, M.H.; Oh, S.H.; Song, J.J.; Chang, K.-H.

    2006-01-01

    AIM: To evaluate spreading patterns of necrotizing external otitis (NEO) by magnetic resonance imaging (MRI) and to identify spreading patterns related to a poor outcome. MATERIALS AND METHODS: Fourteen patients with NEO were divided into good and poor outcome groups according to their final clinical outcomes. Initial MRI images were retrospectively reviewed for regional abnormalities, and follow-up MRI images were reviewed for ICA flow void abnormality and for the following five spreading patterns: medial, crossed, anterior, intracranial, and combined. The frequencies of the abnormal flow void or spreading patterns were compared between the good and poor response groups. RESULTS: Seven (50%) and seven (50%) patients were respectively allocated to the good and poor outcome groups. Retrocondylar fat infiltration was the most commonest finding on initial MRI images (93%). The frequencies of the abnormal flow void and spreading patterns in the good and poor groups, respectively, were: abnormal flow void, 0 and four (57%); anterior, two (29%) and three (43%); medial, six (86%) and seven (100%); crossed, six (86%) and seven (100%); intracranial middle cranial fossa, one (14%) and four (57%); intracranial posterior cranial fossa, four (57%) and six (86%); intracranial foramen magnum, one (14%) and six (86%). CONCLUSIONS: NEO almost always involves the retrocondylar fat and spreads via various pathways to extracranial or intracranial spaces. The presence of an abnormal flow void and intracranial dural enhancement, particularly in the middle cranial fossa and foramen magnum, may indicate a poor prognosis

  1. How to Read the Tractatus Sequentially

    Directory of Open Access Journals (Sweden)

    Tim Kraft

    2016-11-01

    Full Text Available One of the unconventional features of Wittgenstein’s Tractatus Logico-Philosophicus is its use of an elaborated and detailed numbering system. Recently, Bazzocchi, Hacker und Kuusela have argued that the numbering system means that the Tractatus must be read and interpreted not as a sequentially ordered book, but as a text with a two-dimensional, tree-like structure. Apart from being able to explain how the Tractatus was composed, the tree reading allegedly solves exegetical issues both on the local (e. g. how 4.02 fits into the series of remarks surrounding it and the global level (e. g. relation between ontology and picture theory, solipsism and the eye analogy, resolute and irresolute readings. This paper defends the sequential reading against the tree reading. After presenting the challenges generated by the numbering system and the two accounts as attempts to solve them, it is argued that Wittgenstein’s own explanation of the numbering system, anaphoric references within the Tractatus and the exegetical issues mentioned above do not favour the tree reading, but a version of the sequential reading. This reading maintains that the remarks of the Tractatus form a sequential chain: The role of the numbers is to indicate how remarks on different levels are interconnected to form a concise, surveyable and unified whole.

  2. Sequential Modulations in a Combined Horizontal and Vertical Simon Task: Is There ERP Evidence for Feature Integration Effects?

    Science.gov (United States)

    Hoppe, Katharina; Küper, Kristina; Wascher, Edmund

    2017-01-01

    In the Simon task, participants respond faster when the task-irrelevant stimulus position and the response position are corresponding, for example on the same side, compared to when they have a non-corresponding relation. Interestingly, this Simon effect is reduced after non-corresponding trials. Such sequential effects can be explained in terms of a more focused processing of the relevant stimulus dimension due to increased cognitive control, which transfers from the previous non-corresponding trial (conflict adaptation effects). Alternatively, sequential modulations of the Simon effect can also be due to the degree of trial-to-trial repetitions and alternations of task features, which is confounded with the correspondence sequence (feature integration effects). In the present study, we used a spatially two-dimensional Simon task with vertical response keys to examine the contribution of adaptive cognitive control and feature integration processes to the sequential modulation of the Simon effect. The two-dimensional Simon task creates correspondences in the vertical as well as in the horizontal dimension. A trial-by-trial alternation of the spatial dimension, for example from a vertical to a horizontal stimulus presentation, generates a subset containing no complete repetitions of task features, but only complete alternations and partial repetitions, which are equally distributed over all correspondence sequences. In line with the assumed feature integration effects, we found sequential modulations of the Simon effect only when the spatial dimension repeated. At least for the horizontal dimension, this pattern was confirmed by the parietal P3b, an event-related potential that is assumed to reflect stimulus-response link processes. Contrary to conflict adaptation effects, cognitive control, measured by the fronto-central N2 component of the EEG, was not sequentially modulated. Overall, our data provide behavioral as well as electrophysiological evidence for feature

  3. A minimax procedure in the context of sequential mastery testing

    NARCIS (Netherlands)

    Vos, Hendrik J.

    1999-01-01

    The purpose of this paper is to derive optimal rules for sequential mastery tests. In a sequential mastery test, the decision is to classify a subject as a master or a nonmaster, or to continue sampling and administering another random test item. The framework of minimax sequential decision theory

  4. Centroid finding method for position-sensitive detectors

    International Nuclear Information System (INIS)

    Radeka, V.; Boie, R.A.

    1979-10-01

    A new centroid finding method for all detectors where the signal charge is collected or induced on strips of wires, or on subdivided resistive electrodes, is presented. The centroid of charge is determined by convolution of the sequentially switched outputs from these subdivisions or from the strips with a linear centroid finding filter. The position line width is inversely proportional to N/sup 3/2/, where N is the number of subdivisions

  5. Centroid finding method for position-sensitive detectors

    International Nuclear Information System (INIS)

    Radeka, V.; Boie, R.A.

    1980-01-01

    A new centroid finding method for all detectors where the signal charge is collected or induced on strips or wires, or on subdivided resistive electrodes, is presented. The centroid of charge is determined by convolution of the sequentially switched outputs from these subdivisions or from the strips with a linear centroid finding filter. The position line width is inversely proportional to N 3 sup(/) 2 , where N is the number of subdivisions. (orig.)

  6. Understanding User Behavioral Patterns in Open Knowledge Communities

    Science.gov (United States)

    Yang, Xianmin; Song, Shuqiang; Zhao, Xinshuo; Yu, Shengquan

    2018-01-01

    Open knowledge communities (OKCs) have become popular in the era of knowledge economy. This study aimed to explore how users collaboratively create and share knowledge in OKCs. In particular, this research identified the behavior distribution and behavioral patterns of users by conducting frequency distribution and lag sequential analyses. Some…

  7. Sequential MR images of uterus after Gd-DTPA injection

    International Nuclear Information System (INIS)

    Okada, Susumu; Kato, Tomoyasu; Yamada, Keiko; Sawano, Seishi; Yamashita, Takashi; Hirai, Yasuo; Hasumi, Katsuhiko

    1993-01-01

    To investigate the sequential changes in signal intensity (SI) of normal and abnormal uteri, T1-weighted images were taken repeatedly after the injection of Gd-diethylenetriaminepentaacetic acid (DTPA). Six volunteers and 19 patients with known uterine body malignancy (18 carcinomas, one carcinosarcoma) were examined. The results in volunteers were as follows. In the secretory phase, SI of the endometrium was stronger in the late images than in the early ones, whereas in the proliferative phase, SI was stronger in the early images. SI of the myometrium decreased rapidly and there were no differences in SI between menstrual phases. In 17 of 18 endometrial carcinomas, the tumors showed hypointensity relative to the myometrium, and the contrast between the tumor and the myometrium was better in the early images. In the remaining two cases, the tumor showed hyperintensity and the contrast was better in the late images. After the injection of Gd-DTPA, the endometrium appeared differently according to the menstrual cycle in normal volunteers, and the appearance of uterine structures and endometrial malignant tumors changed sequentially. These findings must be kept in mind when evaluating uterine diseases by Gd-DTPA enhanced MRI. (author)

  8. Sequential Banking.

    OpenAIRE

    Bizer, David S; DeMarzo, Peter M

    1992-01-01

    The authors study environments in which agents may borrow sequentially from more than one leader. Although debt is prioritized, additional lending imposes an externality on prior debt because, with moral hazard, the probability of repayment of prior loans decreases. Equilibrium interest rates are higher than they would be if borrowers could commit to borrow from at most one bank. Even though the loan terms are less favorable than they would be under commitment, the indebtedness of borrowers i...

  9. Selective condensation drives partitioning and sequential secretion of cyst wall proteins in differentiating Giardia lamblia.

    Directory of Open Access Journals (Sweden)

    Christian Konrad

    2010-04-01

    Full Text Available Controlled secretion of a protective extracellular matrix is required for transmission of the infective stage of a large number of protozoan and metazoan parasites. Differentiating trophozoites of the highly minimized protozoan parasite Giardia lamblia secrete the proteinaceous portion of the cyst wall material (CWM consisting of three paralogous cyst wall proteins (CWP1-3 via organelles termed encystation-specific vesicles (ESVs. Phylogenetic and molecular data indicate that Diplomonads have lost a classical Golgi during reductive evolution. However, neogenesis of ESVs in encysting Giardia trophozoites transiently provides basic Golgi functions by accumulating presorted CWM exported from the ER for maturation. Based on this "minimal Golgi" hypothesis we predicted maturation of ESVs to a trans Golgi-like stage, which would manifest as a sorting event before regulated secretion of the CWM. Here we show that proteolytic processing of pro-CWP2 in maturing ESVs coincides with partitioning of CWM into two fractions, which are sorted and secreted sequentially with different kinetics. This novel sorting function leads to rapid assembly of a structurally defined outer cyst wall, followed by slow secretion of the remaining components. Using live cell microscopy we find direct evidence for condensed core formation in maturing ESVs. Core formation suggests that a mechanism controlled by phase transitions of the CWM from fluid to condensed and back likely drives CWM partitioning and makes sorting and sequential secretion possible. Blocking of CWP2 processing by a protease inhibitor leads to mis-sorting of a CWP2 reporter. Nevertheless, partitioning and sequential secretion of two portions of the CWM are unaffected in these cells. Although these cysts have a normal appearance they are not water resistant and therefore not infective. Our findings suggest that sequential assembly is a basic architectural principle of protective wall formation and requires

  10. Equivalence between quantum simultaneous games and quantum sequential games

    OpenAIRE

    Kobayashi, Naoki

    2007-01-01

    A framework for discussing relationships between different types of games is proposed. Within the framework, quantum simultaneous games, finite quantum simultaneous games, quantum sequential games, and finite quantum sequential games are defined. In addition, a notion of equivalence between two games is defined. Finally, the following three theorems are shown: (1) For any quantum simultaneous game G, there exists a quantum sequential game equivalent to G. (2) For any finite quantum simultaneo...

  11. Accounting for Heterogeneous Returns in Sequential Schooling Decisions

    NARCIS (Netherlands)

    Zamarro, G.

    2006-01-01

    This paper presents a method for estimating returns to schooling that takes into account that returns may be heterogeneous among agents and that educational decisions are made sequentially.A sequential decision model is interesting because it explicitly considers that the level of education of each

  12. Simultaneous Versus Sequential Ptosis and Strabismus Surgery in Children.

    Science.gov (United States)

    Revere, Karen E; Binenbaum, Gil; Li, Jonathan; Mills, Monte D; Katowitz, William R; Katowitz, James A

    The authors sought to compare the clinical outcomes of simultaneous versus sequential ptosis and strabismus surgery in children. Retrospective, single-center cohort study of children requiring both ptosis and strabismus surgery on the same eye. Simultaneous surgeries were performed during a single anesthetic event; sequential surgeries were performed at least 7 weeks apart. Outcomes were ptosis surgery success (margin reflex distance 1 ≥ 2 mm, good eyelid contour, and good eyelid crease); strabismus surgery success (ocular alignment within 10 prism diopters of orthophoria and/or improved head position); surgical complications; and reoperations. Fifty-six children were studied, 38 had simultaneous surgery and 18 sequential. Strabismus surgery was performed first in 38/38 simultaneous and 6/18 sequential cases. Mean age at first surgery was 64 months, with mean follow up 27 months. A total of 75% of children had congenital ptosis; 64% had comitant strabismus. A majority of ptosis surgeries were frontalis sling (59%) or Fasanella-Servat (30%) procedures. There were no significant differences between simultaneous and sequential groups with regards to surgical success rates, complications, or reoperations (all p > 0.28). In the first comparative study of simultaneous versus sequential ptosis and strabismus surgery, no advantage for sequential surgery was seen. Despite a theoretical risk of postoperative eyelid malposition or complications when surgeries were performed in a combined manner, the rate of such outcomes was not increased with simultaneous surgeries. Performing ptosis and strabismus surgery together appears to be clinically effective and safe, and reduces anesthesia exposure during childhood.

  13. Forced Sequence Sequential Decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis

    In this thesis we describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1/4 and memory M=23, and block interleaved outer Reed-Solomon codes with non-uniform profile. With this scheme decoding with good performance...... is possible as low as Eb/No=0.6 dB, which is about 1.7 dB below the signal-to-noise ratio that marks the cut-off rate for the convolutional code. This is possible since the iteration process provides the sequential decoders with side information that allows a smaller average load and minimizes the probability...... of computational overflow. Analytical results for the probability that the first Reed-Solomon word is decoded after C computations are presented. This is supported by simulation results that are also extended to other parameters....

  14. MotionFlow: Visual Abstraction and Aggregation of Sequential Patterns in Human Motion Tracking Data.

    Science.gov (United States)

    Jang, Sujin; Elmqvist, Niklas; Ramani, Karthik

    2016-01-01

    Pattern analysis of human motions, which is useful in many research areas, requires understanding and comparison of different styles of motion patterns. However, working with human motion tracking data to support such analysis poses great challenges. In this paper, we propose MotionFlow, a visual analytics system that provides an effective overview of various motion patterns based on an interactive flow visualization. This visualization formulates a motion sequence as transitions between static poses, and aggregates these sequences into a tree diagram to construct a set of motion patterns. The system also allows the users to directly reflect the context of data and their perception of pose similarities in generating representative pose states. We provide local and global controls over the partition-based clustering process. To support the users in organizing unstructured motion data into pattern groups, we designed a set of interactions that enables searching for similar motion sequences from the data, detailed exploration of data subsets, and creating and modifying the group of motion patterns. To evaluate the usability of MotionFlow, we conducted a user study with six researchers with expertise in gesture-based interaction design. They used MotionFlow to explore and organize unstructured motion tracking data. Results show that the researchers were able to easily learn how to use MotionFlow, and the system effectively supported their pattern analysis activities, including leveraging their perception and domain knowledge.

  15. Comparison of Sequential Regimen and Standard Therapy for Helicobacter pylori Eradication in Patients with Dyspepsia

    Directory of Open Access Journals (Sweden)

    Gh. Roshanaei

    2013-10-01

    Full Text Available Introduction & Objective: Some studies have reported successful eradication rates using se-quential therapy but more recent studies performed in Asia did not find a similar benefit. Due to inconsistencies in the comparison of standard triple drugs therapy and sequential regimen, in the previous researches we decided to compare these treatments in Persian patients. Materials & Methods: This study is a randomized clinical trial, performed in one hundred and forty patients suffering from dyspepsia with indication for H. pylori eradication between No-vember 2010 and March 2012.Patients were randomized in two equal groups. The patients in the first group (standard were treated by omeprazole capsule 20 mg BID, amoxicillin cap-sule 1 gr BID, clarithromycin tablet 500mg BID for 14 days; while the patients in the second group (sequential were treated by omeprazole capsule 20 mg for 10 days, amoxicillin cap-sule 1 gr BID for 5 days, then clarithromycin tablet 500 mg and tinidazole tablet 500 mg BID for other 5 days. 4-6 weeks after the treatment, we compared the eradication of H.pylori be-tween the two groups by urease breathe test with C14. Results: H. pylori infection was successfully cured in 57/70 (81.43% with a 10-day sequen-tial therapy, in 60/70 (85.75% with the standard fourteen-day triple therapy, respectively. Conclusion: We detected no significant differences between the 10-day sequential eradication therapy for H. pylori and 14-day standard triple treatment among the patients. (Sci J Hamadan Univ Med Sci 2013; 20 (3:184-193

  16. Sequential Classification of Palm Gestures Based on A* Algorithm and MLP Neural Network for Quadrocopter Control

    Directory of Open Access Journals (Sweden)

    Wodziński Marek

    2017-06-01

    Full Text Available This paper presents an alternative approach to the sequential data classification, based on traditional machine learning algorithms (neural networks, principal component analysis, multivariate Gaussian anomaly detector and finding the shortest path in a directed acyclic graph, using A* algorithm with a regression-based heuristic. Palm gestures were used as an example of the sequential data and a quadrocopter was the controlled object. The study includes creation of a conceptual model and practical construction of a system using the GPU to ensure the realtime operation. The results present the classification accuracy of chosen gestures and comparison of the computation time between the CPU- and GPU-based solutions.

  17. Antibody Banding Patterns of the Enzyme-Linked Immunoelectrotransfer Blot and Brain Imaging Findings in Patients With Neurocysticercosis.

    Science.gov (United States)

    Arroyo, Gianfranco; Rodriguez, Silvia; Lescano, Andres G; Alroy, Karen A; Bustos, Javier A; Santivañez, Saul; Gonzales, Isidro; Saavedra, Herbert; Pretell, E Javier; Gonzalez, Armando E; Gilman, Robert H; Tsang, Victor C W; Garcia, Hector H

    2018-01-06

    The enzyme-linked immunoelectrotransfer blot (EITB) assay is the reference serological test for neurocysticercosis (NCC). A positive result on EITB does not always correlate with the presence of active infections in the central nervous system (CNS), and patients with a single viable brain cyst may be EITB negative. Nonetheless, EITB antibody banding patterns appears to be related with the expression of 3 protein families of Taenia solium, and in turn with the characteristics of NCC in the CNS (type, stage, and burden of viable cysts). We evaluated EITB antibody banding patterns and brain imaging findings of 548 NCC cases. Similar banding patterns were grouped into homogeneous classes using latent class analysis. The association between classes and brain imaging findings was assessed. Four classes were identified. Class 1 (patients negative or only positive to the GP50 band, related to the protein family of the same name) was associated with nonviable or single viable parenchymal cysticerci; class 2 (patients positive to bands GP42-39 and GP24, related to the T24-42 protein family, with or without anti-GP50 antibodies) was associated with intraparenchymal viable and nonviable infections; classes 3 and 4 (positive to GP50, GP42-39, and GP24 but also responding to low molecular weight bands GP21, GP18, GP14, and GP13, related to the 8 kDa protein family) were associated with extraparenchymal and intraparenchymal multiple viable cysticerci. EITB antibody banding patterns correlate with brain imaging findings and complement imaging information for the diagnosis of NCC and for staging NCC patients. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  18. Reading Remediation Based on Sequential and Simultaneous Processing.

    Science.gov (United States)

    Gunnison, Judy; And Others

    1982-01-01

    The theory postulating a dichotomy between sequential and simultaneous processing is reviewed and its implications for remediating reading problems are reviewed. Research is cited on sequential-simultaneous processing for early and advanced reading. A list of remedial strategies based on the processing dichotomy addresses decoding and lexical…

  19. Sequential and Parallel Algorithms for Finding a Maximum Convex Polygon

    DEFF Research Database (Denmark)

    Fischer, Paul

    1997-01-01

    This paper investigates the problem where one is given a finite set of n points in the plane each of which is labeled either ?positive? or ?negative?. We consider bounded convex polygons, the vertices of which are positive points and which do not contain any negative point. It is shown how...... such a polygon which is maximal with respect to area can be found in time O(n³ log n). With the same running time one can also find such a polygon which contains a maximum number of positive points. If, in addition, the number of vertices of the polygon is restricted to be at most M, then the running time...... becomes O(M n³ log n). It is also shown how to find a maximum convex polygon which contains a given point in time O(n³ log n). Two parallel algorithms for the basic problem are also presented. The first one runs in time O(n log n) using O(n²) processors, the second one has polylogarithmic time but needs O...

  20. Cognitive processes associated with sequential tool use in New Caledonian crows.

    Directory of Open Access Journals (Sweden)

    Joanna H Wimpenny

    Full Text Available BACKGROUND: Using tools to act on non-food objects--for example, to make other tools--is considered to be a hallmark of human intelligence, and may have been a crucial step in our evolution. One form of this behaviour, 'sequential tool use', has been observed in a number of non-human primates and even in one bird, the New Caledonian crow (Corvus moneduloides. While sequential tool use has often been interpreted as evidence for advanced cognitive abilities, such as planning and analogical reasoning, the behaviour itself can be underpinned by a range of different cognitive mechanisms, which have never been explicitly examined. Here, we present experiments that not only demonstrate new tool-using capabilities in New Caledonian crows, but allow examination of the extent to which crows understand the physical interactions involved. METHODOLOGY/PRINCIPAL FINDINGS: In two experiments, we tested seven captive New Caledonian crows in six tasks requiring the use of up to three different tools in a sequence to retrieve food. Our study incorporated several novel features: (i we tested crows on a three-tool problem (subjects were required to use a tool to retrieve a second tool, then use the second tool to retrieve a third one, and finally use the third one to reach for food; (ii we presented tasks of different complexity in random rather than progressive order; (iii we included a number of control conditions to test whether tool retrieval was goal-directed; and (iv we manipulated the subjects' pre-testing experience. Five subjects successfully used tools in a sequence (four from their first trial, and four subjects repeatedly solved the three-tool condition. Sequential tool use did not require, but was enhanced by, pre-training on each element in the sequence ('chaining', an explanation that could not be ruled out in earlier studies. By analyzing tool choice, tool swapping and improvement over time, we show that successful subjects did not use a random

  1. Normative personality trait development in adulthood: A 6-year cohort-sequential growth model.

    Science.gov (United States)

    Milojev, Petar; Sibley, Chris G

    2017-03-01

    The present study investigated patterns of normative change in personality traits across the adult life span (19 through 74 years of age). We examined change in extraversion, agreeableness, conscientiousness, neuroticism, openness to experience and honesty-humility using data from the first 6 annual waves of the New Zealand Attitudes and Values Study (N = 10,416; 61.1% female, average age = 49.46). We present a cohort-sequential latent growth model assessing patterns of mean-level change due to both aging and cohort effects. Extraversion decreased as people aged, with the most pronounced declines occurring in young adulthood, and then again in old age. Agreeableness, indexed with a measure focusing on empathy, decreased in young adulthood and remained relatively unchanged thereafter. Conscientiousness increased among young adults then leveled off and remained fairly consistent for the rest of the adult life span. Neuroticism and openness to experience decreased as people aged. However, the models suggest that these latter effects may also be partially due to cohort differences, as older people showed lower levels of neuroticism and openness to experience more generally. Honesty-humility showed a pronounced and consistent increase across the adult life span. These analyses of large-scale longitudinal national probability panel data indicate that different dimensions of personality follow distinct developmental processes throughout adulthood. Our findings also highlight the importance of young adulthood (up to about the age of 30) in personality trait development, as well as continuing change throughout the adult life span. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Effect of sequential heat and cold shocks on nuclear phenotypes of the blood-sucking insect, Panstrongylus megistus (Burmeister (Hemiptera, Reduviidae

    Directory of Open Access Journals (Sweden)

    Garcia Simone L

    2002-01-01

    Full Text Available Thermal shocks induce changes in the nuclear phenotypes that correspond to survival (heterochromatin decondensation, nuclear fusion or death (apoptosis, necrosis responses in the Malpighian tubules of Panstrongylus megistus. Since thermal tolerance increased survival and molting rate in this species following sequential shocks, we investigated whether changes in nuclear phenotypes accompanied the insect survival response to sequential thermal shocks. Fifth instar nymphs were subjected to a single heat (35 or 40°C, 1 h or cold (5 or 0°C, 1 h shock and then subjected to a second shock for 12 h at 40 or 0°C, respectively, after 8, 18, 24 and 72 h at 28°C (control temperature. As with specimen survival, sequential heat and cold shocks induced changes in frequency of the mentioned nuclear phenotypes although their patterns differed. The heat shock tolerance involved decrease in apoptosis simultaneous to increase in cell survival responses. Sequential cold shocks did not involve cell/nuclear fusion and even elicited increase in necrosis with advancing time after shocks. The temperatures of 40 and 0ºC were more effective than the temperatures of 35 and 5ºC in eliciting the heat and cold shock tolerances, respectively, as shown by cytological analysis of the nuclear phenotypes. It is concluded that different sequential thermal shocks can trigger different mechanisms of cellular protection against stress in P. megistus, favoring the insect to adapt to various ecotopes.

  3. Pattern of Presentation of Multiple Organ Dysfunction Syndrome in ...

    African Journals Online (AJOL)

    Background: Multiple organ dysfunction syndrome is the sequential failure of several organ systems after a trigger event, like sepsis, massive transfusions, burns, trauma and cardiogenic shock. Aim and Objectives- The pattern of presentation of multiple organ dysfunction and the risk factors associated with multiple organ ...

  4. Top-down attention affects sequential regularity representation in the human visual system.

    Science.gov (United States)

    Kimura, Motohiro; Widmann, Andreas; Schröger, Erich

    2010-08-01

    Recent neuroscience studies using visual mismatch negativity (visual MMN), an event-related brain potential (ERP) index of memory-mismatch processes in the visual sensory system, have shown that although sequential regularities embedded in successive visual stimuli can be automatically represented in the visual sensory system, an existence of sequential regularity itself does not guarantee that the sequential regularity will be automatically represented. In the present study, we investigated the effects of top-down attention on sequential regularity representation in the visual sensory system. Our results showed that a sequential regularity (SSSSD) embedded in a modified oddball sequence where infrequent deviant (D) and frequent standard stimuli (S) differing in luminance were regularly presented (SSSSDSSSSDSSSSD...) was represented in the visual sensory system only when participants attended the sequential regularity in luminance, but not when participants ignored the stimuli or simply attended the dimension of luminance per se. This suggests that top-down attention affects sequential regularity representation in the visual sensory system and that top-down attention is a prerequisite for particular sequential regularities to be represented. Copyright 2010 Elsevier B.V. All rights reserved.

  5. Modelling the sequential geographical exploitation and potential collapse of marine fisheries through economic globalization, climate change and management alternatives

    Directory of Open Access Journals (Sweden)

    Gorka Merino

    2011-07-01

    Full Text Available Global marine fisheries production has reached a maximum and may even be declining. Underlying this trend is a well-understood sequence of development, overexploitation, depletion and in some instances collapse of individual fish stocks, a pattern that can sequentially link geographically distant populations. Ineffective governance, economic considerations and climate impacts are often responsible for this sequence, although the relative contribution of each factor is contentious. In this paper we use a global bioeconomic model to explore the synergistic effects of climate variability, economic pressures and management measures in causing or avoiding this sequence. The model shows how a combination of climate-induced variability in the underlying fish population production, particular patterns of demand for fish products and inadequate management is capable of driving the world’s fisheries into development, overexploitation, collapse and recovery phases consistent with observations. Furthermore, it demonstrates how a sequential pattern of overexploitation can emerge as an endogenous property of the interaction between regional environmental fluctuations and a globalized trade system. This situation is avoidable through adaptive management measures that ensure the sustainability of regional production systems in the face of increasing global environmental change and markets. It is concluded that global management measures are needed to ensure that global food supply from marine products is optimized while protecting long-term ecosystem services across the world’s oceans.

  6. Fast sequential Monte Carlo methods for counting and optimization

    CERN Document Server

    Rubinstein, Reuven Y; Vaisman, Radislav

    2013-01-01

    A comprehensive account of the theory and application of Monte Carlo methods Based on years of research in efficient Monte Carlo methods for estimation of rare-event probabilities, counting problems, and combinatorial optimization, Fast Sequential Monte Carlo Methods for Counting and Optimization is a complete illustration of fast sequential Monte Carlo techniques. The book provides an accessible overview of current work in the field of Monte Carlo methods, specifically sequential Monte Carlo techniques, for solving abstract counting and optimization problems. Written by authorities in the

  7. Computing sequential equilibria for two-player games

    DEFF Research Database (Denmark)

    Miltersen, Peter Bro

    2006-01-01

    Koller, Megiddo and von Stengel showed how to efficiently compute minimax strategies for two-player extensive-form zero-sum games with imperfect information but perfect recall using linear programming and avoiding conversion to normal form. Their algorithm has been used by AI researchers...... for constructing prescriptive strategies for concrete, often fairly large games. Koller and Pfeffer pointed out that the strategies obtained by the algorithm are not necessarily sequentially rational and that this deficiency is often problematic for the practical applications. We show how to remove this deficiency...... by modifying the linear programs constructed by Koller, Megiddo and von Stengel so that pairs of strategies forming a sequential equilibrium are computed. In particular, we show that a sequential equilibrium for a two-player zero-sum game with imperfect information but perfect recall can be found in polynomial...

  8. In vivo imaging of GABAA receptors using sequential whole-volume iodine-123 iomazenil single-photon emission tomography

    International Nuclear Information System (INIS)

    Busatto, G.F.; Pilowsky, L.S.; Costa, D.C.; Ell, P.J.; Lingford-Hughes, A.; Kerwin, R.W.

    1995-01-01

    Using a brain-dedicated triple-headed single-photon emission tomography (SPET) system, a sequential whole-volume imaging protocol has been devised to evaluate the regional distribution of iodine-123 iomazenil binding to GABA A receptors in the entire brain. The protocol was piloted in eight normal volunteers (seven males and one female; mean age, 24.8±3.9 years). The patterns obtained were largely compatible with the known distribution of GABA A receptors in the brain as reported in autoradiographic studies, with cerebral cortical regions, particularly the occipital and frontal cortices, displaying the highest 123 I-iomazenil uptake. Measures of time to peak uptake and tracer washout rates presented with the same pattern of regional variation, with later times to peak and slower washout rates in cortical regions compared to other brain areas. Semiquantitative analysis of the data using white matter/ventricle regions as reference demonstrated a plateau of specific 123 I-iomazenil binding in neocortical and cerebellar regions from 60-75 min onwards. These data demonstrate the feasibility of sequential, dynamic whole-volume 123 I-iomazenil SPET imaging. The protocol may be particularly useful in the investigation of neuropsychiatric conditions which are likely to involve more than one focus of GABA abnormalities, such as anxiety disorders and schizophrenia. (orig.)

  9. Sensitivity Analysis in Sequential Decision Models.

    Science.gov (United States)

    Chen, Qiushi; Ayer, Turgay; Chhatwal, Jagpreet

    2017-02-01

    Sequential decision problems are frequently encountered in medical decision making, which are commonly solved using Markov decision processes (MDPs). Modeling guidelines recommend conducting sensitivity analyses in decision-analytic models to assess the robustness of the model results against the uncertainty in model parameters. However, standard methods of conducting sensitivity analyses cannot be directly applied to sequential decision problems because this would require evaluating all possible decision sequences, typically in the order of trillions, which is not practically feasible. As a result, most MDP-based modeling studies do not examine confidence in their recommended policies. In this study, we provide an approach to estimate uncertainty and confidence in the results of sequential decision models. First, we provide a probabilistic univariate method to identify the most sensitive parameters in MDPs. Second, we present a probabilistic multivariate approach to estimate the overall confidence in the recommended optimal policy considering joint uncertainty in the model parameters. We provide a graphical representation, which we call a policy acceptability curve, to summarize the confidence in the optimal policy by incorporating stakeholders' willingness to accept the base case policy. For a cost-effectiveness analysis, we provide an approach to construct a cost-effectiveness acceptability frontier, which shows the most cost-effective policy as well as the confidence in that for a given willingness to pay threshold. We demonstrate our approach using a simple MDP case study. We developed a method to conduct sensitivity analysis in sequential decision models, which could increase the credibility of these models among stakeholders.

  10. A one-sided sequential test

    Energy Technology Data Exchange (ETDEWEB)

    Racz, A.; Lux, I. [Hungarian Academy of Sciences, Budapest (Hungary). Atomic Energy Research Inst.

    1996-04-16

    The applicability of the classical sequential probability ratio testing (SPRT) for early failure detection problems is limited by the fact that there is an extra time delay between the occurrence of the failure and its first recognition. Chien and Adams developed a method to minimize this time for the case when the problem can be formulated as testing the mean value of a Gaussian signal. In our paper we propose a procedure that can be applied for both mean and variance testing and that minimizes the time delay. The method is based on a special parametrization of the classical SPRT. The one-sided sequential tests (OSST) can reproduce the results of the Chien-Adams test when applied for mean values. (author).

  11. Sequential inference as a mode of cognition and its correlates in fronto-parietal and hippocampal brain regions.

    Directory of Open Access Journals (Sweden)

    Thomas H B FitzGerald

    2017-05-01

    Full Text Available Normative models of human cognition often appeal to Bayesian filtering, which provides optimal online estimates of unknown or hidden states of the world, based on previous observations. However, in many cases it is necessary to optimise beliefs about sequences of states rather than just the current state. Importantly, Bayesian filtering and sequential inference strategies make different predictions about beliefs and subsequent choices, rendering them behaviourally dissociable. Taking data from a probabilistic reversal task we show that subjects' choices provide strong evidence that they are representing short sequences of states. Between-subject measures of this implicit sequential inference strategy had a neurobiological underpinning and correlated with grey matter density in prefrontal and parietal cortex, as well as the hippocampus. Our findings provide, to our knowledge, the first evidence for sequential inference in human cognition, and by exploiting between-subject variation in this measure we provide pointers to its neuronal substrates.

  12. Evolving antithrombotic treatment patterns for patients with newly diagnosed atrial fibrillation

    NARCIS (Netherlands)

    Camm, A.J.; Accetta, G.; Ambrosio, G.; Atar, D.; Bassand, J.P.; Berge, E. van de; Cools, F.; Fitzmaurice, D.A.; Goldhaber, S.Z.; Goto, S.; Haas, S.; Kayani, G.; Koretsune, Y.; Mantovani, L.G.; Misselwitz, F.; Oh, S.; Turpie, A.G.G.; Verheugt, F.W.A.; Kakkar, A.K.

    2017-01-01

    OBJECTIVE: We studied evolving antithrombotic therapy patterns in patients with newly diagnosed non-valvular atrial fibrillation (AF) and >/=1 additional stroke risk factor between 2010 and 2015. METHODS: 39 670 patients were prospectively enrolled in four sequential cohorts in the Global

  13. Discrimination between sequential and simultaneous virtual channels with electrical hearing

    OpenAIRE

    Landsberger, David; Galvin, John J.

    2011-01-01

    In cochlear implants (CIs), simultaneous or sequential stimulation of adjacent electrodes can produce intermediate pitch percepts between those of the component electrodes. However, it is unclear whether simultaneous and sequential virtual channels (VCs) can be discriminated. In this study, CI users were asked to discriminate simultaneous and sequential VCs; discrimination was measured for monopolar (MP) and bipolar + 1 stimulation (BP + 1), i.e., relatively broad and focused stimulation mode...

  14. Statistical learning of recurring sound patterns encodes auditory objects in songbird forebrain.

    Science.gov (United States)

    Lu, Kai; Vicario, David S

    2014-10-07

    Auditory neurophysiology has demonstrated how basic acoustic features are mapped in the brain, but it is still not clear how multiple sound components are integrated over time and recognized as an object. We investigated the role of statistical learning in encoding the sequential features of complex sounds by recording neuronal responses bilaterally in the auditory forebrain of awake songbirds that were passively exposed to long sound streams. These streams contained sequential regularities, and were similar to streams used in human infants to demonstrate statistical learning for speech sounds. For stimulus patterns with contiguous transitions and with nonadjacent elements, single and multiunit responses reflected neuronal discrimination of the familiar patterns from novel patterns. In addition, discrimination of nonadjacent patterns was stronger in the right hemisphere than in the left, and may reflect an effect of top-down modulation that is lateralized. Responses to recurring patterns showed stimulus-specific adaptation, a sparsening of neural activity that may contribute to encoding invariants in the sound stream and that appears to increase coding efficiency for the familiar stimuli across the population of neurons recorded. As auditory information about the world must be received serially over time, recognition of complex auditory objects may depend on this type of mnemonic process to create and differentiate representations of recently heard sounds.

  15. Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

    Science.gov (United States)

    Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

    2016-01-01

    Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

  16. Sequential dependencies in magnitude scaling of loudness

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Jesteadt, Walt

    2013-01-01

    Ten normally hearing listeners used a programmable sone-potentiometer knob to adjust the level of a 1000-Hz sinusoid to match the loudness of numbers presented to them in a magnitude production task. Three different power-law exponents (0.15, 0.30, and 0.60) and a log-law with equal steps in d......B were used to program the sone-potentiometer. The knob settings systematically influenced the form of the loudness function. Time series analysis was used to assess the sequential dependencies in the data, which increased with increasing exponent and were greatest for the log-law. It would be possible......, therefore, to choose knob properties that minimized these dependencies. When the sequential dependencies were removed from the data, the slope of the loudness functions did not change, but the variability decreased. Sequential dependencies were only present when the level of the tone on the previous trial...

  17. A SEQUENTIAL MODEL OF INNOVATION STRATEGY—COMPANY NON-FINANCIAL PERFORMANCE LINKS

    Directory of Open Access Journals (Sweden)

    Wakhid Slamet Ciptono

    2006-05-01

    dimensions of innovation strategy (partially mediators to company non-financial performance —productivity or operational reliability. The findings provide empirical evidence extending the previous model of Zahra and Das. These findings also provide a basis for useful recommendations to upstream and downstream SBU managers attempting to implement a sequential model of innovation strategy —company non-financial performance links. This study shows that upstream SBUs rely on external innovation sources. They will acquire innovation policies through business partnership development (such as Joint Operation Body for Enhanced Oil Recovery or JOB-EOR, Joint Operation Body for Production Sharing Contract or JOB-PSC; licensing agreements (Technical Assistance Contract or TAC, Consortium Cooperation System; or acquisition with other firms (Joint Operating Contract or JOC. In contrast, downstream SBUs emphasize on generating internal innovation sources to develop their own in-house R&D efforts. The downstream SBUs should make extensive policies of internal innovation sources in their attempts to control the distribution of oil-based fuel and transmission of natural gas for domestic and international markets effectively. Both policies would enhance understanding and ultimately contribute to the improvement of company financial performance —sales, net profit margin, return on assets.

  18. Sequential egocentric navigation and reliance on landmarks in Williams syndrome and typical development

    Directory of Open Access Journals (Sweden)

    Hannah eBroadbent

    2015-02-01

    Full Text Available Visuospatial difficulties in Williams syndrome (WS are well documented. Recently, research has shown that spatial difficulties in WS extend to large-scale space, particularly in coding space using an allocentric frame of reference. Typically developing (TD children and adults predominantly rely on the use of a sequential egocentric strategy to navigate a large-scale route (retracing a sequence of left-right body turns. The aim of this study was to examine whether individuals with WS are able to employ a sequential egocentric strategy to guide learning and the retracing of a route. Forty-eight TD children, aged 5, 7 and 9 years and 18 participants with WS were examined on their ability to learn and retrace routes in two (6-turn virtual environment mazes (with and without landmarks. The ability to successfully retrace a route following the removal of landmarks (use of sequential egocentric coding was also examined.Although in line with TD 5 year-olds when learning a route with landmarks, individuals with WS showed significantly greater detriment when these landmarks were removed, relative to all TD groups. Moreover, the WS group made significantly more errors than all TD groups when learning a route that never contained landmarks. On a perceptual view-matching task, results revealed a high level of performance across groups, indicative of an ability to use this visual information to potentially aid navigation. These findings suggest that individuals with WS rely on landmarks to a greater extent than TD children, both for learning a route and for retracing a recently learned route. TD children, but not individuals with WS, were able to fall back on the use of a sequential egocentric strategy to navigate when landmarks were not present. Only TD children therefore coded sequential route information simultaneously with landmark information. The results are discussed in relation to known atypical cortical development and perceptual-matching abilities

  19. Multimodal sensory integration during sequential eating--linking chewing activity, aroma release, and aroma perception over time.

    Science.gov (United States)

    Leclercq, Ségolène; Blancher, Guillaume

    2012-10-01

    The respective effects of chewing activity, aroma release from a gelled candy, and aroma perception were investigated. Specifically, the study aimed at 1) comparing an imposed chewing and swallowing pattern (IP) and free protocol (FP) on panelists for in vivo measurements, 2) investigating carryover effects in sequential eating, and 3) studying the link between instrumental data and their perception counterpart. Chewing activity, in-nose aroma concentration, and aroma perception over time were measured by electromyography, proton transfer reaction-mass spectrometry, and time intensity, respectively. Model gel candies were flavored at 2 intensity levels (low-L and high-H). The panelists evaluated 3 sequences (H then H, H then L, and L then H) in duplicates with both IP and FP. They scored aroma intensity over time while their in-nose aroma concentrations and their chewing activity were measured. Overall, only limited advantages were found in imposing a chewing and swallowing pattern for instrumental and sensory data. In addition, the study highlighted the role of brain integration on perceived intensity and dynamics of perception, in the framework of sequential eating without rinsing. Because of the presence of adaptation phenomena, contrast effect, and potential taste and texture cross-modal interaction with aroma perception, it was concluded that dynamic in-nose concentration data provide only one part of the perception picture and therefore cannot be used alone in prediction models.

  20. Short-term memory for spatial, sequential and duration information.

    Science.gov (United States)

    Manohar, Sanjay G; Pertzov, Yoni; Husain, Masud

    2017-10-01

    Space and time appear to play key roles in the way that information is organized in short-term memory (STM). Some argue that they are crucial contexts within which other stored features are embedded, allowing binding of information that belongs together within STM. Here we review recent behavioral, neurophysiological and imaging studies that have sought to investigate the nature of spatial, sequential and duration representations in STM, and how these might break down in disease. Findings from these studies point to an important role of the hippocampus and other medial temporal lobe structures in aspects of STM, challenging conventional accounts of involvement of these regions in only long-term memory.

  1. SCRLH-TL Based Sequential Rotation Feed Network for Broadband Circularly Polarized Antenna Array

    Directory of Open Access Journals (Sweden)

    B. F. Zong

    2016-04-01

    Full Text Available In this paper, a broadband circularly polarized (CP microstrip antenna array using composite right/left-handed transmission line (SCRLH-TL based sequential rotation (SR feed network is presented. The characteristics of a SCRLH-TL are initially investigated. Then, a broadband and low insertion loss 45º phase shifter is designed using the SCRLH-TL and the phase shifter is employed in constructing a SR feed network for CP antenna array. To validate the design method of the SR feed network, a 2×2 antenna array comprising sequentially rotated coupled stacked CP antenna elements is designed, fabricated and measured. Both the simulated and measured results indicate that the performances of the antenna element are further enhanced when the SR network is used. The antenna array exhibits the VSWR less than 1.8 dB from 4 GHz to 7 GHz and the 3 dB axial ratio (AR from 4.4 GHz to 6.8 GHz. Also, high peak gain of 13.7 dBic is obtained. Besides, the normalized radiation patterns at the operating frequencies are symmetrical and the side lobe levels are low at φ=0º and φ=90º.

  2. The effects of sequential attention shifts within visual working memory

    Directory of Open Access Journals (Sweden)

    Qi eLi

    2014-09-01

    Full Text Available Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: 1 orienting attention to one location, and then withdrawing attention from it, and 2 switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed benefits of both the first and second cues in sequential cueing, indicating that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance at the first-cued location was still better than the neutral baseline or performance at the uncued locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance.

  3. Global patterns and substrate-based mechanisms of the terrestrial nitrogen cycle

    DEFF Research Database (Denmark)

    Niu, Shuli; Classen, Aimee Taylor; Dukes, Jeffrey S.

    2016-01-01

    availability but increase exponentially and become the dominant fate of N at high loading rates. The original N saturation hypothesis emphasises sequential N saturation from plant uptake to soil retention before N losses occur. However, biogeochemical models that simulate simultaneous competition for soil N...... substrates by multiple processes match the observed patterns of N losses better than models based on sequential competition. To enable better prediction of terrestrial N cycle responses to N loading, we recommend that future research identifies the response functions of different N processes to substrate...

  4. The sequential price of anarchy for atomic congestion games

    NARCIS (Netherlands)

    de Jong, Jasper; Uetz, Marc Jochen; Liu, Tie-Yan; Qi, Qi; Ye, Yinyu

    2014-01-01

    In situations without central coordination, the price of anarchy relates the quality of any Nash equilibrium to the quality of a global optimum. Instead of assuming that all players choose their actions simultaneously, we consider games where players choose their actions sequentially. The sequential

  5. Comparing brain white matter on sequential cranial ultrasound and MRI in very preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Leijser, Lara M.; Veen, Sylvia; Boer, Inge P. de; Walther, Frans J.; Wezel-Meijler, Gerda van [Leiden University Medical Center, Department of Pediatrics, Division of Neonatology, Albinusdreef 2, P.O. Box 9600, Leiden (Netherlands); Liauw, Lishya [Leiden University Medical Center, Department of Radiology, Division of Neuroradiology, Albinusdreef 2, P.O. Box 9600, Leiden (Netherlands)

    2008-09-15

    Periventricular white matter (WM) echodensities, frequently seen in preterm infants, can be associated with suboptimal neurodevelopment. Major WM injury is well detected on cranial ultrasound (cUS). cUS seems less sensitive for diffuse or more subtle WM injury. Our aim was to assess the value of cUS and magnetic resonance imaging (MRI) for evaluating WM changes and the predictive value of cUS and/or MRI findings for neurodevelopmental outcome in very preterm infants with normal to severely abnormal WM on sequential high-quality cUS. Very preterm infants (<32 weeks) who had sequential cUS and one MRI within the first three postnatal months were included. Periventricular WM on cUS and MRI was compared and correlated with neurodevelopmental outcome at 2 years corrected age. Forty preterm infants were studied; outcome data were available in 32. WM changes on sequential cUS were predictive of WM changes on MRI. Severely abnormal WM on cUS/MRI was predictive of adverse outcome, and normal-mildly abnormal WM of favorable outcome. Moderately abnormal WM on cUS/MRI was associated with variable outcome. Additional MRI slightly increased the predictive value of cUS in severe WM changes. Sequential cUS in preterm infants is reliable for detecting WM changes and predicting favorable and severely abnormal outcome. Conventional and diffusion-weighted MRI sequences before term equivalent age in very preterm infants, suggested on cUS to have mild to moderately abnormal WM, do not seem to be warranted. (orig.)

  6. Comparing brain white matter on sequential cranial ultrasound and MRI in very preterm infants

    International Nuclear Information System (INIS)

    Leijser, Lara M.; Veen, Sylvia; Boer, Inge P. de; Walther, Frans J.; Wezel-Meijler, Gerda van; Liauw, Lishya

    2008-01-01

    Periventricular white matter (WM) echodensities, frequently seen in preterm infants, can be associated with suboptimal neurodevelopment. Major WM injury is well detected on cranial ultrasound (cUS). cUS seems less sensitive for diffuse or more subtle WM injury. Our aim was to assess the value of cUS and magnetic resonance imaging (MRI) for evaluating WM changes and the predictive value of cUS and/or MRI findings for neurodevelopmental outcome in very preterm infants with normal to severely abnormal WM on sequential high-quality cUS. Very preterm infants (<32 weeks) who had sequential cUS and one MRI within the first three postnatal months were included. Periventricular WM on cUS and MRI was compared and correlated with neurodevelopmental outcome at 2 years corrected age. Forty preterm infants were studied; outcome data were available in 32. WM changes on sequential cUS were predictive of WM changes on MRI. Severely abnormal WM on cUS/MRI was predictive of adverse outcome, and normal-mildly abnormal WM of favorable outcome. Moderately abnormal WM on cUS/MRI was associated with variable outcome. Additional MRI slightly increased the predictive value of cUS in severe WM changes. Sequential cUS in preterm infants is reliable for detecting WM changes and predicting favorable and severely abnormal outcome. Conventional and diffusion-weighted MRI sequences before term equivalent age in very preterm infants, suggested on cUS to have mild to moderately abnormal WM, do not seem to be warranted. (orig.)

  7. Encoding Sequential Information in Semantic Space Models: Comparing Holographic Reduced Representation and Random Permutation

    Directory of Open Access Journals (Sweden)

    Gabriel Recchia

    2015-01-01

    Full Text Available Circular convolution and random permutation have each been proposed as neurally plausible binding operators capable of encoding sequential information in semantic memory. We perform several controlled comparisons of circular convolution and random permutation as means of encoding paired associates as well as encoding sequential information. Random permutations outperformed convolution with respect to the number of paired associates that can be reliably stored in a single memory trace. Performance was equal on semantic tasks when using a small corpus, but random permutations were ultimately capable of achieving superior performance due to their higher scalability to large corpora. Finally, “noisy” permutations in which units are mapped to other units arbitrarily (no one-to-one mapping perform nearly as well as true permutations. These findings increase the neurological plausibility of random permutations and highlight their utility in vector space models of semantics.

  8. Solid state perovskite solar modules by vacuum-vapor assisted sequential deposition on Nd:YVO_4 laser patterned rutile TiO_2 nanorods

    International Nuclear Information System (INIS)

    Fakharuddin, Azhar; Wali, Qamar; Rauf, Muhammad; Jose, Rajan; Palma, Alessandro L; Giacomo, Francesco Di; Casaluci, Simone; Matteocci, Fabio; Carlo, Aldo Di; Brown, Thomas M

    2015-01-01

    The past few years have witnessed remarkable progress in solution-processed methylammonium lead halide (CH_3NH_3PbX_3, X = halide) perovskite solar cells (PSCs) with reported photoconversion efficiency (η) exceeding 20% in laboratory-scale devices and reaching up to 13% in their large area perovskite solar modules (PSMs). These devices mostly employ mesoporous TiO_2 nanoparticles (NPs) as an electron transport layer (ETL) which provides a scaffold on which the perovskite semiconductor can grow. However, limitations exist which are due to trap-limited electron transport and non-complete pore filling. Herein, we have employed TiO_2 nanorods (NRs), a material offering a two-fold higher electronic mobility and higher pore-filing compared to their particle analogues, as an ETL. A crucial issue in NRs’ patterning over substrates is resolved by using precise Nd:YVO_4 laser ablation, and a champion device with η ∼ 8.1% is reported via a simple and low cost vacuum-vapor assisted sequential processing (V-VASP) of a CH_3NH_3PbI_3 film. Our experiments showed a successful demonstration of NRs-based PSMs via the V-VASP technique which can be applied to fabricate large area modules with a pin-hole free, smooth and dense perovskite layer which is required to build high efficiency devices. (paper)

  9. Simultaneous and sequential hemorrhage of multiple cerebral cavernous malformations: a case report.

    Science.gov (United States)

    Louis, Nundia; Marsh, Robert

    2016-02-09

    The etiology of cerebral cavernous malformation hemorrhage is not well understood. Causative physiologic parameters preceding hemorrhagic cavernous malformation events are often not reported. We present a case of an individual with sequential simultaneous hemorrhages in multiple cerebral cavernous malformations with a new onset diagnosis of hypertension. A 42-year-old white man was admitted to our facility with worsening headache, left facial and tongue numbness, dizziness, diplopia, and elevated blood pressure. His past medical history was significant for new onset diagnosis of hypertension and chronic seasonal allergies. Serial imaging over the ensuing 8 days revealed sequential hemorrhagic lesions. He underwent suboccipital craniotomy for resection of the lesions located in the fourth ventricle and right cerebellum. One month after surgery, he had near complete resolution of his symptoms with mild residual vertigo but symptomatic chronic hypertension. Many studies have focused on genetic and inflammatory mechanisms contributing to cerebral cavernous malformation rupture, but few have reported on the potential of hemodynamic changes contributing to cerebral cavernous malformation rupture. Systemic blood pressure changes clearly have an effect on angioma pressures. When considering the histopathological features of cerebral cavernous malformation architecture, changes in arterial pressure could cause meaningful alterations in hemorrhage propensity and patterns.

  10. Campbell and moment measures for finite sequential spatial processes

    NARCIS (Netherlands)

    M.N.M. van Lieshout (Marie-Colette)

    2006-01-01

    textabstractWe define moment and Campbell measures for sequential spatial processes, prove a Campbell-Mecke theorem, and relate the results to their counterparts in the theory of point processes. In particular, we show that any finite sequential spatial process model can be derived as the vector

  11. The importance of examining movements within the US health care system: sequential logit modeling

    Directory of Open Access Journals (Sweden)

    Lee Chioun

    2010-09-01

    Full Text Available Abstract Background Utilization of specialty care may not be a discrete, isolated behavior but rather, a behavior of sequential movements within the health care system. Although patients may often visit their primary care physician and receive a referral before utilizing specialty care, prior studies have underestimated the importance of accounting for these sequential movements. Methods The sample included 6,772 adults aged 18 years and older who participated in the 2001 Survey on Disparities in Quality of Care, sponsored by the Commonwealth Fund. A sequential logit model was used to account for movement in all stages of utilization: use of any health services (i.e., first stage, having a perceived need for specialty care (i.e., second stage, and utilization of specialty care (i.e., third stage. In the sequential logit model, all stages are nested within the previous stage. Results Gender, race/ethnicity, education and poor health had significant explanatory effects with regard to use of any health services and having a perceived need for specialty care, however racial/ethnic, gender, and educational disparities were not present in utilization of specialty care. After controlling for use of any health services and having a perceived need for specialty care, inability to pay for specialty care via income (AOR = 1.334, CI = 1.10 to 1.62 or health insurance (unstable insurance: AOR = 0.26, CI = 0.14 to 0.48; no insurance: AOR = 0.12, CI = 0.07 to 0.20 were significant barriers to utilization of specialty care. Conclusions Use of a sequential logit model to examine utilization of specialty care resulted in a detailed representation of utilization behaviors and patient characteristics that impact these behaviors at all stages within the health care system. After controlling for sequential movements within the health care system, the biggest barrier to utilizing specialty care is the inability to pay, while racial, gender, and educational disparities

  12. Sequential Dependencies in Driving

    Science.gov (United States)

    Doshi, Anup; Tran, Cuong; Wilder, Matthew H.; Mozer, Michael C.; Trivedi, Mohan M.

    2012-01-01

    The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find…

  13. Default activity patterns at the neocortical microcircuit level

    Directory of Open Access Journals (Sweden)

    Artur eLuczak

    2012-06-01

    Full Text Available Even in absence of sensory stimuli cortical networks exhibit complex, self-organized activity patterns. While the function of those spontaneous patterns of activation remains poorly understood, recent studies both in vivo and in vitro have demonstrated that neocortical neurons activate in a surprisingly similar sequential order both spontaneously and following input into cortex. For example, neurons that tend to fire earlier within spontaneous bursts of activity also fire earlier than other neurons in response to sensory stimuli. These 'default patterns' can last hundreds of milliseconds and are strongly conserved under a variety of conditions. In this paper we will review recent evidence for these default patterns at the local cortical level. We speculate that cortical architecture imposes common constraints on spontaneous and evoked activity flow, which result in the similarity of the patterns.

  14. Sinonasal carcinoma presenting as chronic sinusitis and sequential bilateral visual loss

    Directory of Open Access Journals (Sweden)

    Wei-Yu Chiang

    2015-01-01

    Full Text Available Sinonasal undifferentiated carcinoma-related rhinogenic optic neuropathy is rare and may lead to visual loss. To the best of our knowledge, this is the first report of bilateral sequential visual loss induced by this etiology. It is important to differentiate between chronic sinusitis and malignancy on the basis of specific findings on magnetic resonance images. Surgical decompression with multidisciplinary therapy, including steroids, chemotherapy, and radiotherapy, is indicated. However, no visual improvement was noted in this case, emphasizing the rapid disease progression and importance of early diagnosis and treatment.

  15. Asymptotically optimum multialternative sequential procedures for discernment of processes minimizing average length of observations

    Science.gov (United States)

    Fishman, M. M.

    1985-01-01

    The problem of multialternative sequential discernment of processes is formulated in terms of conditionally optimum procedures minimizing the average length of observations, without any probabilistic assumptions about any one occurring process, rather than in terms of Bayes procedures minimizing the average risk. The problem is to find the procedure that will transform inequalities into equalities. The problem is formulated for various models of signal observation and data processing: (1) discernment of signals from background interference by a multichannel system; (2) discernment of pulse sequences with unknown time delay; (3) discernment of harmonic signals with unknown frequency. An asymptotically optimum sequential procedure is constructed which compares the statistics of the likelihood ratio with the mean-weighted likelihood ratio and estimates the upper bound for conditional average lengths of observations. This procedure is shown to remain valid as the upper bound for the probability of erroneous partial solutions decreases approaching zero and the number of hypotheses increases approaching infinity. It also remains valid under certain special constraints on the probability such as a threshold. A comparison with a fixed-length procedure reveals that this sequential procedure decreases the length of observations to one quarter, on the average, when the probability of erroneous partial solutions is low.

  16. Short-Range Temporal Interactions in Sleep; Hippocampal Spike Avalanches Support a Large Milieu of Sequential Activity Including Replay.

    Directory of Open Access Journals (Sweden)

    J Matthew Mahoney

    Full Text Available Hippocampal neural systems consolidate multiple complex behaviors into memory. However, the temporal structure of neural firing supporting complex memory consolidation is unknown. Replay of hippocampal place cells during sleep supports the view that a simple repetitive behavior modifies sleep firing dynamics, but does not explain how multiple episodes could be integrated into associative networks for recollection during future cognition. Here we decode sequential firing structure within spike avalanches of all pyramidal cells recorded in sleeping rats after running in a circular track. We find that short sequences that combine into multiple long sequences capture the majority of the sequential structure during sleep, including replay of hippocampal place cells. The ensemble, however, is not optimized for maximally producing the behavior-enriched episode. Thus behavioral programming of sequential correlations occurs at the level of short-range interactions, not whole behavioral sequences and these short sequences are assembled into a large and complex milieu that could support complex memory consolidation.

  17. A Game of Hide and Seek: Expectations of Clumpy Resources Influence Hiding and Searching Patterns.

    Directory of Open Access Journals (Sweden)

    Andreas Wilke

    Full Text Available Resources are often distributed in clumps or patches in space, unless an agent is trying to protect them from discovery and theft using a dispersed distribution. We uncover human expectations of such spatial resource patterns in collaborative and competitive settings via a sequential multi-person game in which participants hid resources for the next participant to seek. When collaborating, resources were mostly hidden in clumpy distributions, but when competing, resources were hidden in more dispersed (random or hyperdispersed patterns to increase the searching difficulty for the other player. More dispersed resource distributions came at the cost of higher overall hiding (as well as searching times, decreased payoffs, and an increased difficulty when the hider had to recall earlier hiding locations at the end of the experiment. Participants' search strategies were also affected by their underlying expectations, using a win-stay lose-shift strategy appropriate for clumpy resources when searching for collaboratively-hidden items, but moving equally far after finding or not finding an item in competitive settings, as appropriate for dispersed resources. Thus participants showed expectations for clumpy versus dispersed spatial resources that matched the distributions commonly found in collaborative versus competitive foraging settings.

  18. Framework for sequential approximate optimization

    NARCIS (Netherlands)

    Jacobs, J.H.; Etman, L.F.P.; Keulen, van F.; Rooda, J.E.

    2004-01-01

    An object-oriented framework for Sequential Approximate Optimization (SAO) isproposed. The framework aims to provide an open environment for thespecification and implementation of SAO strategies. The framework is based onthe Python programming language and contains a toolbox of Python

  19. A Survey of Multi-Objective Sequential Decision-Making

    OpenAIRE

    Roijers, D.M.; Vamplew, P.; Whiteson, S.; Dazeley, R.

    2013-01-01

    Sequential decision-making problems with multiple objectives arise naturally in practice and pose unique challenges for research in decision-theoretic planning and learning, which has largely focused on single-objective settings. This article surveys algorithms designed for sequential decision-making problems with multiple objectives. Though there is a growing body of literature on this subject, little of it makes explicit under what circumstances special methods are needed to solve multi-obj...

  20. A Sequential Multiplicative Extended Kalman Filter for Attitude Estimation Using Vector Observations

    Science.gov (United States)

    Qin, Fangjun; Jiang, Sai; Zha, Feng

    2018-01-01

    In this paper, a sequential multiplicative extended Kalman filter (SMEKF) is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms. PMID:29751538

  1. A Sequential Multiplicative Extended Kalman Filter for Attitude Estimation Using Vector Observations

    Directory of Open Access Journals (Sweden)

    Fangjun Qin

    2018-05-01

    Full Text Available In this paper, a sequential multiplicative extended Kalman filter (SMEKF is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms.

  2. Asynchronous Operators of Sequential Logic Venjunction & Sequention

    CERN Document Server

    Vasyukevich, Vadim

    2011-01-01

    This book is dedicated to new mathematical instruments assigned for logical modeling of the memory of digital devices. The case in point is logic-dynamical operation named venjunction and venjunctive function as well as sequention and sequentional function. Venjunction and sequention operate within the framework of sequential logic. In a form of the corresponding equations, they organically fit analytical expressions of Boolean algebra. Thus, a sort of symbiosis is formed using elements of asynchronous sequential logic on the one hand and combinational logic on the other hand. So, asynchronous

  3. Food Consumption Patterns: Findings from the Malaysian Adult Nutrition Survey (MANS).

    Science.gov (United States)

    Norimah, A K; Safiah, M; Jamal, K; Haslinda, Siti; Zuhaida, H; Rohida, S; Fatimah, S; Norazlin, Siti; Poh, B K; Kandiah, M; Zalilah, M S; Wan Manan, W M; Fatimah, S; Azmi, M Y

    2008-03-01

    % of adults below 20 years old consumed chicken at least once a day, while this pattern of intake was not shown in the older age groups. Our findings show that adults, aged 50 to 59 years old, had the highest prevalence of daily consumption of full cream milk with 24% while those aged 18 to 19 years old had the lowest prevalence of daily consumption at 15%. The food consumption pattern of Malaysian adults appears to be satisfactory. However, some changes in food habits are recommended especially in substituting the less wholesome sweetened condensed milk with the more nutritious full cream or skimmed milk.

  4. [Injury patterns and roentgen findings in gunshot wounds with rare flint ammunition].

    Science.gov (United States)

    Pollak, S; Lindermann, A

    1990-01-01

    Smoothbore shotgun barrels can fire cartridges with common pellet loads as well as shotgun slugs and rubber bullets. Other than conventional shot, the cylindrical Brenneke-type rifled shotgun slugs sometimes cause perforating wounds. The shotgun ammunition for use in self-defence can have a single projectile or several rubber pellets. Where the propellant is black powder, short range shots will probably leave searing marks and intensive soot deposits. Fired at close range, rubber bullets can penetrate through the skin into the body, fired at greater distance they cause contusions. A case of homicide (repeated firing with a 12-ga. pump gun) is used to present and discuss the injury patterns and X-ray findings after impact of Brenneke-type slugs and rubber bullets as well as of "classical" shot pellets.

  5. Pass/fail patterns of candidates who failed COMLEX-USA level 2-PE because of misrepresentation of clinical findings on postencounter notes.

    Science.gov (United States)

    Langenau, Erik E; Sandella, Jeanne M

    2011-07-01

    In 2007, The National Board of Osteopathic Medical Examiners (NBOME) instituted a policy to address the accuracy and integrity of postencounter written documentation recorded during the Comprehensive Osteopathic Medical Licensing Examination Level 2-Performance Evaluation (COMLEX-USA Level 2-PE). This policy was instituted not only to protect the integrity of the examination, but also to highlight that overdocumentation of clinical findings not obtained during patient encounters may jeopardize patient safety. To investigate overall and domain pass/fail patterns of candidates who misrepresented clinical findings with regard to past and subsequent performance on COMLEX-USA Level 2-PE. Specifically, to investigate what percentage of candidates failed because of misrepresentation on first attempts and how they performed on subsequent administrations, as well as the previous performance patterns of candidates who failed because of misrepresentation on examination retakes. Historical records from NBOME's COMLEX-USA Level 2-PE database (testing cycles 2007-2008, 2008-2009, and 2009-2010) were used to analyze overall and domain pass/fail patterns of candidates who failed at least once because of misrepresentation of clinical findings. Of the 24 candidates who failed because of misrepresentation of postencounter (SOAP) notes, 20 candidates (83%) were first-time examinees. Four candidates (17%) were repeating the examination, 2 of whom were making a third attempt to pass. Among these 20 candidates who failed because of misrepresentation of clinical findings on their first attempt, 19 passed on their next attempt. At the time of study analysis, all but 2 candidates eventually passed the examination in subsequent attempts. Among candidates found to have misrepresented clinical findings on postencounter written documentation on COMLEX-USA Level 2-PE, no pattern existed between their past or subsequent performance with regard to overall or domain pass/fail results. The vast

  6. The structure and evolution of galacto-detonation waves - Some analytic results in sequential star formation models of spiral galaxies

    Science.gov (United States)

    Cowie, L. L.; Rybicki, G. B.

    1982-01-01

    Waves of star formation in a uniform, differentially rotating disk galaxy are treated analytically as a propagating detonation wave front. It is shown, that if single solitary waves could be excited, they would evolve asymptotically to one of two stable spiral forms, each of which rotates with a fixed pattern speed. Simple numerical solutions confirm these results. However, the pattern of waves that develop naturally from an initially localized disturbance is more complex and dies out within a few rotation periods. These results suggest a conclusive observational test for deciding whether sequential star formation is an important determinant of spiral structure in some class of galaxies.

  7. Human visual system automatically encodes sequential regularities of discrete events.

    Science.gov (United States)

    Kimura, Motohiro; Schröger, Erich; Czigler, István; Ohira, Hideki

    2010-06-01

    For our adaptive behavior in a dynamically changing environment, an essential task of the brain is to automatically encode sequential regularities inherent in the environment into a memory representation. Recent studies in neuroscience have suggested that sequential regularities embedded in discrete sensory events are automatically encoded into a memory representation at the level of the sensory system. This notion is largely supported by evidence from investigations using auditory mismatch negativity (auditory MMN), an event-related brain potential (ERP) correlate of an automatic memory-mismatch process in the auditory sensory system. However, it is still largely unclear whether or not this notion can be generalized to other sensory modalities. The purpose of the present study was to investigate the contribution of the visual sensory system to the automatic encoding of sequential regularities using visual mismatch negativity (visual MMN), an ERP correlate of an automatic memory-mismatch process in the visual sensory system. To this end, we conducted a sequential analysis of visual MMN in an oddball sequence consisting of infrequent deviant and frequent standard stimuli, and tested whether the underlying memory representation of visual MMN generation contains only a sensory memory trace of standard stimuli (trace-mismatch hypothesis) or whether it also contains sequential regularities extracted from the repetitive standard sequence (regularity-violation hypothesis). The results showed that visual MMN was elicited by first deviant (deviant stimuli following at least one standard stimulus), second deviant (deviant stimuli immediately following first deviant), and first standard (standard stimuli immediately following first deviant), but not by second standard (standard stimuli immediately following first standard). These results are consistent with the regularity-violation hypothesis, suggesting that the visual sensory system automatically encodes sequential

  8. Impact of Diagrams on Recalling Sequential Elements in Expository Texts.

    Science.gov (United States)

    Guri-Rozenblit, Sarah

    1988-01-01

    Examines the instructional effectiveness of abstract diagrams on recall of sequential relations in social science textbooks. Concludes that diagrams assist significantly the recall of sequential relations in a text and decrease significantly the rate of order mistakes. (RS)

  9. A polynomial time biclustering algorithm for finding approximate expression patterns in gene expression time series

    Directory of Open Access Journals (Sweden)

    Madeira Sara C

    2009-06-01

    Full Text Available Abstract Background The ability to monitor the change in expression patterns over time, and to observe the emergence of coherent temporal responses using gene expression time series, obtained from microarray experiments, is critical to advance our understanding of complex biological processes. In this context, biclustering algorithms have been recognized as an important tool for the discovery of local expression patterns, which are crucial to unravel potential regulatory mechanisms. Although most formulations of the biclustering problem are NP-hard, when working with time series expression data the interesting biclusters can be restricted to those with contiguous columns. This restriction leads to a tractable problem and enables the design of efficient biclustering algorithms able to identify all maximal contiguous column coherent biclusters. Methods In this work, we propose e-CCC-Biclustering, a biclustering algorithm that finds and reports all maximal contiguous column coherent biclusters with approximate expression patterns in time polynomial in the size of the time series gene expression matrix. This polynomial time complexity is achieved by manipulating a discretized version of the original matrix using efficient string processing techniques. We also propose extensions to deal with missing values, discover anticorrelated and scaled expression patterns, and different ways to compute the errors allowed in the expression patterns. We propose a scoring criterion combining the statistical significance of expression patterns with a similarity measure between overlapping biclusters. Results We present results in real data showing the effectiveness of e-CCC-Biclustering and its relevance in the discovery of regulatory modules describing the transcriptomic expression patterns occurring in Saccharomyces cerevisiae in response to heat stress. In particular, the results show the advantage of considering approximate patterns when compared to state of

  10. Quantum Probability Zero-One Law for Sequential Terminal Events

    Science.gov (United States)

    Rehder, Wulf

    1980-07-01

    On the basis of the Jauch-Piron quantum probability calculus a zero-one law for sequential terminal events is proven, and the significance of certain crucial axioms in the quantum probability calculus is discussed. The result shows that the Jauch-Piron set of axioms is appropriate for the non-Boolean algebra of sequential events.

  11. A path-level exact parallelization strategy for sequential simulation

    Science.gov (United States)

    Peredo, Oscar F.; Baeza, Daniel; Ortiz, Julián M.; Herrero, José R.

    2018-01-01

    Sequential Simulation is a well known method in geostatistical modelling. Following the Bayesian approach for simulation of conditionally dependent random events, Sequential Indicator Simulation (SIS) method draws simulated values for K categories (categorical case) or classes defined by K different thresholds (continuous case). Similarly, Sequential Gaussian Simulation (SGS) method draws simulated values from a multivariate Gaussian field. In this work, a path-level approach to parallelize SIS and SGS methods is presented. A first stage of re-arrangement of the simulation path is performed, followed by a second stage of parallel simulation for non-conflicting nodes. A key advantage of the proposed parallelization method is to generate identical realizations as with the original non-parallelized methods. Case studies are presented using two sequential simulation codes from GSLIB: SISIM and SGSIM. Execution time and speedup results are shown for large-scale domains, with many categories and maximum kriging neighbours in each case, achieving high speedup results in the best scenarios using 16 threads of execution in a single machine.

  12. Concatenated coding system with iterated sequential inner decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Paaske, Erik

    1995-01-01

    We describe a concatenated coding system with iterated sequential inner decoding. The system uses convolutional codes of very long constraint length and operates on iterations between an inner Fano decoder and an outer Reed-Solomon decoder......We describe a concatenated coding system with iterated sequential inner decoding. The system uses convolutional codes of very long constraint length and operates on iterations between an inner Fano decoder and an outer Reed-Solomon decoder...

  13. Role of Transbronchial Lung Cryobiopsies in Diffuse Parenchymal Lung Diseases: Interest of a Sequential Approach

    Directory of Open Access Journals (Sweden)

    Benjamin Bondue

    2017-01-01

    Full Text Available Background. Transbronchial lung cryobiopsies (TBLCs are a promising diagnostic tool in the setting of diffuse parenchymal lung diseases (DPLDs. However, no comparison with surgical lung biopsy (SLB in the same patient is available. Methods. The diagnostic yield and safety data of TBLCs, as well as the result of SLB performed after TBLCs, were analysed in a multicentric Belgian study. A SLB was performed after TBLCs in absence of a definite pathological diagnosis or if a NSIP pattern was observed without related condition identified following multidisciplinary discussion. Results. Between April 2015 and November 2016, 30 patients were included. Frequent complications included pneumothorax (20% and bleeding (severe 7%, moderate 33%, and mild 53%. There was no mortality. The overall diagnostic yield was 80%. A SLB was performed in six patients (three without definite histological pattern and three with an NSIP. The surgical biopsy changed the pathological diagnosis into a UIP pattern in five patients and confirmed a NSIP pattern in one patient. Conclusion. TBLCs are useful in the diagnostic work-up of DPLDs avoiding a SLB in 80% of the patients. However, surgical biopsies, performed as a second step after TBLCs because of an indefinite diagnosis or a NSIP pattern, provide additional information supporting the interest of a sequential approach in these patients.

  14. In vivo imaging of GABA{sub A} receptors using sequential whole-volume iodine-123 iomazenil single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Busatto, G.F. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Pilowsky, L.S. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Costa, D.C. [Inst. of Nuclear Medicine, University Coll. and Middlesex School of Medicine, London (United Kingdom); Ell, P.J. [Inst. of Nuclear Medicine, University Coll. and Middlesex School of Medicine, London (United Kingdom); Lingford-Hughes, A. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Kerwin, R.W. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom)

    1995-01-01

    Using a brain-dedicated triple-headed single-photon emission tomography (SPET) system, a sequential whole-volume imaging protocol has been devised to evaluate the regional distribution of iodine-123 iomazenil binding to GABA{sub A} receptors in the entire brain. The protocol was piloted in eight normal volunteers (seven males and one female; mean age, 24.8{+-}3.9 years). The patterns obtained were largely compatible with the known distribution of GABA{sub A} receptors in the brain as reported in autoradiographic studies, with cerebral cortical regions, particularly the occipital and frontal cortices, displaying the highest {sup 123}I-iomazenil uptake. Measures of time to peak uptake and tracer washout rates presented with the same pattern of regional variation, with later times to peak and slower washout rates in cortical regions compared to other brain areas. Semiquantitative analysis of the data using white matter/ventricle regions as reference demonstrated a plateau of specific {sup 123}I-iomazenil binding in neocortical and cerebellar regions from 60-75 min onwards. These data demonstrate the feasibility of sequential, dynamic whole-volume {sup 123}I-iomazenil SPET imaging. The protocol may be particularly useful in the investigation of neuropsychiatric conditions which are likely to involve more than one focus of GABA abnormalities, such as anxiety disorders and schizophrenia. (orig.)

  15. Lineup Composition, Suspect Position, and the Sequential Lineup Advantage

    Science.gov (United States)

    Carlson, Curt A.; Gronlund, Scott D.; Clark, Steven E.

    2008-01-01

    N. M. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001) argued that sequential lineups reduce the likelihood of mistaken eyewitness identification. Experiment 1 replicated the design of R. C. L. Lindsay and G. L. Wells (1985), the first study to show the sequential lineup advantage. However, the innocent suspect was chosen at a lower rate…

  16. Trial Sequential Analysis in systematic reviews with meta-analysis

    Directory of Open Access Journals (Sweden)

    Jørn Wetterslev

    2017-03-01

    Full Text Available Abstract Background Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size. The results of the meta-analyses should relate the total number of randomised participants to the estimated required meta-analytic information size accounting for statistical diversity. When the number of participants and the corresponding number of trials in a meta-analysis are insufficient, the use of the traditional 95% confidence interval or the 5% statistical significance threshold will lead to too many false positive conclusions (type I errors and too many false negative conclusions (type II errors. Methods We developed a methodology for interpreting meta-analysis results, using generally accepted, valid evidence on how to adjust thresholds for significance in randomised clinical trials when the required sample size has not been reached. Results The Lan-DeMets trial sequential monitoring boundaries in Trial Sequential Analysis offer adjusted confidence intervals and restricted thresholds for statistical significance when the diversity-adjusted required information size and the corresponding number of required trials for the meta-analysis have not been reached. Trial Sequential Analysis provides a frequentistic approach to control both type I and type II errors. We define the required information size and the corresponding number of required trials in a meta-analysis and the diversity (D2 measure of heterogeneity. We explain the reasons for using Trial Sequential Analysis of meta-analysis when the actual information size fails to reach the required information size. We present examples drawn from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in

  17. Simultaneous or Early Sequential Rupture of Multiple Intracranial Aneurysms: A Rare and Insufficiently Understood Entity.

    Science.gov (United States)

    Hou, Kun; Zhao, Jinchuan; Zhang, Yang; Zhu, Xiaobo; Zhao, Yan; Li, Guichen

    2016-05-01

    Simultaneous or early sequential rupture of multiple intracranial aneurysms (MIAs) is encountered rarely, with no more than 10 cases having been reported. As a result of its rarity, there are a lot of questions concerning this entity need to be answered. A 67-year-old woman was admitted to the First Hospital of Jilin University (Eastern Division) from a local hospital after a sudden onset of severe headache, nausea, and vomiting. Head computed tomography (CT) at the local hospital revealed diffuse subarachnoid hemorrhage (SAH) that was concentrated predominately in the suprasellar cistern and interhemispheric fissure. During her transfer to our hospital, she experienced another episode of sudden headache. CT on admission to our hospital revealed that the SAH was increased with 2 isolated hematomas both in the interhemispheric fissure and the left paramedian frontal lobe. Further CT angiography and intraoperative findings were in favor of early sequential rupture of 2 intracranial aneurysms. To further elucidate the characteristics, mechanism, management, and prognosis of this specific entity, we conducted a comprehensive review of the literature. The mechanism of simultaneous or early sequential rupture of MIAs is still obscure. Transient elevation of blood pressure might play a role in the process, and preventing the sudden elevation of blood pressure might be beneficial for patients with aneurysmal SAH and MIAs. The management of simultaneously or early sequentially ruptured aneurysms is more complex for its difficulty in responsible aneurysm determination, urgency in treatment, toughness in intraoperative manipulation and poorness in prognosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Is sequential cranial ultrasound reliable for detection of white matter injury in very preterm infants?

    International Nuclear Information System (INIS)

    Leijser, Lara M.; Steggerda, Sylke J.; Walther, Frans J.; Wezel-Meijler, Gerda van; Bruine, Francisca T. de; Grond, Jeroen van der

    2010-01-01

    Cranial ultrasound (cUS) may not be reliable for detection of diffuse white matter (WM) injury. Our aim was to assess in very preterm infants the reliability of a classification system for WM injury on sequential cUS throughout the neonatal period, using magnetic resonance imaging (MRI) as reference standard. In 110 very preterm infants (gestational age <32 weeks), serial cUS during admission (median 8, range 4-22) and again around term equivalent age (TEA) and a single MRI around TEA were performed. cUS during admission were assessed for presence of WM changes, and contemporaneous cUS and MRI around TEA additionally for abnormality of lateral ventricles. Sequential cUS (from birth up to TEA) and MRI were classified as normal/mildly abnormal, moderately abnormal, or severely abnormal, based on a combination of findings of the WM and lateral ventricles. Predictive values of the cUS classification were calculated. Sequential cUS were classified as normal/mildly abnormal, moderately abnormal, and severely abnormal in, respectively, 22%, 65%, and 13% of infants and MRI in, respectively, 30%, 52%, and 18%. The positive predictive value of the cUS classification for the MRI classification was high for severely abnormal WM (0.79) but lower for normal/mildly abnormal (0.67) and moderately abnormal (0.64) WM. Sequential cUS during the neonatal period detects severely abnormal WM in very preterm infants but is less reliable for mildly and moderately abnormal WM. MRI around TEA seems needed to reliably detect WM injury in very preterm infants. (orig.)

  19. Heat accumulation during sequential cortical bone drilling.

    Science.gov (United States)

    Palmisano, Andrew C; Tai, Bruce L; Belmont, Barry; Irwin, Todd A; Shih, Albert; Holmes, James R

    2016-03-01

    Significant research exists regarding heat production during single-hole bone drilling. No published data exist regarding repetitive sequential drilling. This study elucidates the phenomenon of heat accumulation for sequential drilling with both Kirschner wires (K wires) and standard two-flute twist drills. It was hypothesized that cumulative heat would result in a higher temperature with each subsequent drill pass. Nine holes in a 3 × 3 array were drilled sequentially on moistened cadaveric tibia bone kept at body temperature (about 37 °C). Four thermocouples were placed at the center of four adjacent holes and 2 mm below the surface. A battery-driven hand drill guided by a servo-controlled motion system was used. Six samples were drilled with each tool (2.0 mm K wire and 2.0 and 2.5 mm standard drills). K wire drilling increased temperature from 5 °C at the first hole to 20 °C at holes 6 through 9. A similar trend was found in standard drills with less significant increments. The maximum temperatures of both tools increased from drill sizes was found to be insignificant (P > 0.05). In conclusion, heat accumulated during sequential drilling, with size difference being insignificant. K wire produced more heat than its twist-drill counterparts. This study has demonstrated the heat accumulation phenomenon and its significant effect on temperature. Maximizing the drilling field and reducing the number of drill passes may decrease bone injury. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  20. Sequential growth factor application in bone marrow stromal cell ligament engineering.

    Science.gov (United States)

    Moreau, Jodie E; Chen, Jingsong; Horan, Rebecca L; Kaplan, David L; Altman, Gregory H

    2005-01-01

    In vitro bone marrow stromal cell (BMSC) growth may be enhanced through culture medium supplementation, mimicking the biochemical environment in which cells optimally proliferate and differentiate. We hypothesize that the sequential administration of growth factors to first proliferate and then differentiate BMSCs cultured on silk fiber matrices will support the enhanced development of ligament tissue in vitro. Confluent second passage (P2) BMSCs obtained from purified bone marrow aspirates were seeded on RGD-modified silk matrices. Seeded matrices were divided into three groups for 5 days of static culture, with medium supplement of basic fibroblast growth factor (B) (1 ng/mL), epidermal growth factor (E; 1 ng/mL), or growth factor-free control (C). After day 5, medium supplementation was changed to transforming growth factor-beta1 (T; 5 ng/mL) or C for an additional 9 days of culture. Real-time RT-PCR, SEM, MTT, histology, and ELISA for collagen type I of all sample groups were performed. Results indicated that BT supported the greatest cell ingrowth after 14 days of culture in addition to the greatest cumulative collagen type I expression measured by ELISA. Sequential growth factor application promoted significant increases in collagen type I transcript expression from day 5 of culture to day 14, for five of six groups tested. All T-supplemented samples surpassed their respective control samples in both cell ingrowth and collagen deposition. All samples supported spindle-shaped, fibroblast cell morphology, aligning with the direction of silk fibers. These findings indicate significant in vitro ligament development after only 14 days of culture when using a sequential growth factor approach.

  1. Prevalence and correlates of atypical patterns of drug use progression: findings from the South African Stress and Health Study

    Science.gov (United States)

    Myers, B; van Heerden, MS; Grimsrud, A; Myer, L; Williams, DR; Stein, DJ

    2012-01-01

    Objective Atypical sequences of drug use progression are thought to have important implications for the development of substance dependence. The extent to which this assumption holds for South African populations is unknown. This paper attempts to address this gap by examining the prevalence and correlates of atypical patterns of drug progression among South Africans. Method Data on substance use and other mental health disorders from a nationally representative sample of 4351 South Africans were analysed. Weighted cross tabulations were used to estimate prevalence and correlates of atypical patterns of drug use progression. Results Overall, 12.2% of the sample reported atypical patterns of drug use progression. The most common violation was the use of extra-medical drugs prior to alcohol and tobacco. Gender was significantly associated with atypical patterns of drug use with the risk pattern varying by the type of drug. None of the anxiety or mood disorders were associated with atypical patterns of use. Atypical patterns of drug use were not associated with increased risk for a lifetime substance use disorder. Conclusion Atypical patterns of drug use initiation seem more prevalent in South Africa compared to other countries. The early use of extra-medical drugs is common, especially among young women. Drug availability and social environmental factors may influence patterns of drug use. The findings have important implications for prevention initiatives and future research. PMID:21509404

  2. Cost-effectiveness of simultaneous versus sequential surgery in head and neck reconstruction.

    Science.gov (United States)

    Wong, Kevin K; Enepekides, Danny J; Higgins, Kevin M

    2011-02-01

    To determine whether simultaneous (ablation and reconstruction overlaps by two teams) head and neck reconstruction is cost effective compared to sequentially (ablation followed by reconstruction) performed surgery. Case-controlled study. Tertiary care hospital. Oncology patients undergoing free flap reconstruction of the head and neck. A match paired comparison study was performed with a retrospective chart review examining the total time of surgery for sequential and simultaneous surgery. Nine patients were selected for both the sequential and simultaneous groups. Sequential head and neck reconstruction patients were pair matched with patients who had undergone similar oncologic ablative or reconstructive procedures performed in a simultaneous fashion. A detailed cost analysis using the microcosting method was then undertaken looking at the direct costs of the surgeons, anesthesiologist, operating room, and nursing. On average, simultaneous surgery required 3 hours 15 minutes less operating time, leading to a cost savings of approximately $1200/case when compared to sequential surgery. This represents approximately a 15% reduction in the cost of the entire operation. Simultaneous head and neck reconstruction is more cost effective when compared to sequential surgery.

  3. The role of chemometrics in single and sequential extraction assays: a review. Part II. Cluster analysis, multiple linear regression, mixture resolution, experimental design and other techniques.

    Science.gov (United States)

    Giacomino, Agnese; Abollino, Ornella; Malandrino, Mery; Mentasti, Edoardo

    2011-03-04

    Single and sequential extraction procedures are used for studying element mobility and availability in solid matrices, like soils, sediments, sludge, and airborne particulate matter. In the first part of this review we reported an overview on these procedures and described the applications of chemometric uni- and bivariate techniques and of multivariate pattern recognition techniques based on variable reduction to the experimental results obtained. The second part of the review deals with the use of chemometrics not only for the visualization and interpretation of data, but also for the investigation of the effects of experimental conditions on the response, the optimization of their values and the calculation of element fractionation. We will describe the principles of the multivariate chemometric techniques considered, the aims for which they were applied and the key findings obtained. The following topics will be critically addressed: pattern recognition by cluster analysis (CA), linear discriminant analysis (LDA) and other less common techniques; modelling by multiple linear regression (MLR); investigation of spatial distribution of variables by geostatistics; calculation of fractionation patterns by a mixture resolution method (Chemometric Identification of Substrates and Element Distributions, CISED); optimization and characterization of extraction procedures by experimental design; other multivariate techniques less commonly applied. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Dihydroazulene photoswitch operating in sequential tunneling regime

    DEFF Research Database (Denmark)

    Broman, Søren Lindbæk; Lara-Avila, Samuel; Thisted, Christine Lindbjerg

    2012-01-01

    to electrodes so that the electron transport goes by sequential tunneling. To assure weak coupling, the DHA switching kernel is modified by incorporating p-MeSC6H4 end-groups. Molecules are prepared by Suzuki cross-couplings on suitable halogenated derivatives of DHA. The synthesis presents an expansion of our......, incorporating a p-MeSC6H4 anchoring group in one end, has been placed in a silver nanogap. Conductance measurements justify that transport through both DHA (high resistivity) and VHF (low resistivity) forms goes by sequential tunneling. The switching is fairly reversible and reenterable; after more than 20 ON...

  5. A Trust-region-based Sequential Quadratic Programming Algorithm

    DEFF Research Database (Denmark)

    Henriksen, Lars Christian; Poulsen, Niels Kjølstad

    This technical note documents the trust-region-based sequential quadratic programming algorithm used in other works by the authors. The algorithm seeks to minimize a convex nonlinear cost function subject to linear inequalty constraints and nonlinear equality constraints.......This technical note documents the trust-region-based sequential quadratic programming algorithm used in other works by the authors. The algorithm seeks to minimize a convex nonlinear cost function subject to linear inequalty constraints and nonlinear equality constraints....

  6. Sequential search leads to faster, more efficient fragment-based de novo protein structure prediction.

    Science.gov (United States)

    de Oliveira, Saulo H P; Law, Eleanor C; Shi, Jiye; Deane, Charlotte M

    2018-04-01

    Most current de novo structure prediction methods randomly sample protein conformations and thus require large amounts of computational resource. Here, we consider a sequential sampling strategy, building on ideas from recent experimental work which shows that many proteins fold cotranslationally. We have investigated whether a pseudo-greedy search approach, which begins sequentially from one of the termini, can improve the performance and accuracy of de novo protein structure prediction. We observed that our sequential approach converges when fewer than 20 000 decoys have been produced, fewer than commonly expected. Using our software, SAINT2, we also compared the run time and quality of models produced in a sequential fashion against a standard, non-sequential approach. Sequential prediction produces an individual decoy 1.5-2.5 times faster than non-sequential prediction. When considering the quality of the best model, sequential prediction led to a better model being produced for 31 out of 41 soluble protein validation cases and for 18 out of 24 transmembrane protein cases. Correct models (TM-Score > 0.5) were produced for 29 of these cases by the sequential mode and for only 22 by the non-sequential mode. Our comparison reveals that a sequential search strategy can be used to drastically reduce computational time of de novo protein structure prediction and improve accuracy. Data are available for download from: http://opig.stats.ox.ac.uk/resources. SAINT2 is available for download from: https://github.com/sauloho/SAINT2. saulo.deoliveira@dtc.ox.ac.uk. Supplementary data are available at Bioinformatics online.

  7. Photoluminescence of Sequential Infiltration Synthesized ZnO nanostructures

    Science.gov (United States)

    Ocola, Leonidas; Gosztola, David; Yanguas-Gil, Angel; Connolly, Aine

    We have investigated a variation of atomic layer deposition (ALD), called sequential infiltration synthesis (SiS), as an alternate method to incorporate ZnO and other oxides inside polymethylmethacrylate (PMMA) and other polymers. Energy dispersive spectroscopy (EDS) results show that we synthesize ZnO up to 300 nm inside a PMMA film. Photoluminescence data on a PMMA film shows that we achieve a factor of 400X increase in photoluminescence (PL) intensity when comparing a blank Si sample and a 270 nm thick PMMA film, where both were treated with the same 12 alternating cycles of H2O and diethyl zinc (DEZ). PMMA is a well-known ebeam resist. We can expose and develop patterns useful for photonics or sensing applications first, and then convert them afterwards into a hybrid polymer-oxide material. We show that patterning does indeed affect the photoluminescence signature of native ZnO. We demonstrate we can track the growth of the ZnO inside the PMMA polymer using both photoluminescence and Raman spectroscopy and determine the point in the process where ZnO is first photoluminescent and also at which point ZnO first exhibits long range order in the polymer. This work was supported by the Department of Energy under Contract No. DE-AC02-06CH11357. Use of the Center for Nanoscale Materials was supported by the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  8. Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    Kortbek, Jacob; Jensen, Jørgen Arendt; Gammelmark, Kim Løkke

    2008-01-01

    A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective is to im......A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective...... is to improve and obtain a more range independent lateral resolution compared to conventional dynamic receive focusing (DRF) without compromising frame rate. SASB is a two-stage procedure using two separate beamformers. First a set of Bmode image lines using a single focal point in both transmit and receive...... is stored. The second stage applies the focused image lines from the first stage as input data. The SASB method has been investigated using simulations in Field II and by off-line processing of data acquired with a commercial scanner. The performance of SASB with a static image object is compared with DRF...

  9. Evaluation Using Sequential Trials Methods.

    Science.gov (United States)

    Cohen, Mark E.; Ralls, Stephen A.

    1986-01-01

    Although dental school faculty as well as practitioners are interested in evaluating products and procedures used in clinical practice, research design and statistical analysis can sometimes pose problems. Sequential trials methods provide an analytical structure that is both easy to use and statistically valid. (Author/MLW)

  10. Attack Trees with Sequential Conjunction

    NARCIS (Netherlands)

    Jhawar, Ravi; Kordy, Barbara; Mauw, Sjouke; Radomirović, Sasa; Trujillo-Rasua, Rolando

    2015-01-01

    We provide the first formal foundation of SAND attack trees which are a popular extension of the well-known attack trees. The SAND at- tack tree formalism increases the expressivity of attack trees by intro- ducing the sequential conjunctive operator SAND. This operator enables the modeling of

  11. Stochastic Modeling of Usage Patterns in a Web-Based Information System.

    Science.gov (United States)

    Chen, Hui-Min; Cooper, Michael D.

    2002-01-01

    Uses continuous-time stochastic models, mainly based on semi-Markov chains, to derive user state transition patterns, both in rates and in probabilities, in a Web-based information system. Describes search sessions from transaction logs of the University of California's MELVYL library catalog system and discusses sequential dependency. (Author/LRW)

  12. Properties of simultaneous and sequential two-nucleon transfer

    International Nuclear Information System (INIS)

    Pinkston, W.T.; Satchler, G.R.

    1982-01-01

    Approximate forms of the first- and second-order distorted-wave Born amplitudes are used to study the overall structure, particularly the selection rules, of the amplitudes for simultaneous and sequential transfer of two nucleons. The role of the spin-state assumed for the intermediate deuterons in sequential (t, p) reactions is stressed. The similarity of one-step and two-step amplitudes for (α, d) reactions is exhibited, and the consequent absence of any obvious J-dependence in their interference is noted. (orig.)

  13. The Teaching of General Solution Methods to Pattern Finding Problems through Focusing on an Evaluation and Improvement Process.

    Science.gov (United States)

    Ishida, Junichi

    1997-01-01

    Examines the effects of a teaching strategy in which fifth-grade students evaluated the strengths or weaknesses of solution methods to pattern finding problems, including an experimental and control group each consisting of 34 elementary students, in Japan. The experimental group showed a significantly better performance on the retention test…

  14. Influence of sequential room-temperature compressive creep on flow stress of TA2

    Science.gov (United States)

    Mengyuan, Zhang; Boqin, Gu; Jiahui, Tao

    2018-03-01

    This paper studied the sequential room temperature compressive creep and its effects on compressive properties of TA2 with stress-control loading pattern by using cylindrical compressive test specimen. The significant time-dependent deformation under constant load was observed in the TA2 at room temperature, and the deformation was dependent on the loading process under the same loading stress rate. It was also found that the occurrence of room temperature compressive creep obviously enhanced the subsequent yielding strength and flow stress of TA2 due to the increase of network dislocation density. And the effects of room temperature creep on the strain rate-stress behavior could be explained by the local mobile dislocation density model.

  15. Patterns of Force, Sequences of Resistance

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz; Daniël De Vries, Thomas; Bernasco, Wim

    2018-01-01

    Robberies are improvised encounters involving offender threat, sometimes force, and often victim resistance. While the association between threat, force, and resistance in robberies is well-established, sequential patterns are disputed due to biases of retrospective studies. To overcome these bia...... the likelihood of victim resistance despite having no effect on offender vio- lence. By providing more reliable and detailed accounts of real-life behavior during robberies, our analysis illustrates the potential of a newly emergent field of studies of crimes caught on camera....

  16. Synthesizing genetic sequential logic circuit with clock pulse generator.

    Science.gov (United States)

    Chuang, Chia-Hua; Lin, Chun-Liang

    2014-05-28

    Rhythmic clock widely occurs in biological systems which controls several aspects of cell physiology. For the different cell types, it is supplied with various rhythmic frequencies. How to synthesize a specific clock signal is a preliminary but a necessary step to further development of a biological computer in the future. This paper presents a genetic sequential logic circuit with a clock pulse generator based on a synthesized genetic oscillator, which generates a consecutive clock signal whose frequency is an inverse integer multiple to that of the genetic oscillator. An analogous electronic waveform-shaping circuit is constructed by a series of genetic buffers to shape logic high/low levels of an oscillation input in a basic sinusoidal cycle and generate a pulse-width-modulated (PWM) output with various duty cycles. By controlling the threshold level of the genetic buffer, a genetic clock pulse signal with its frequency consistent to the genetic oscillator is synthesized. A synchronous genetic counter circuit based on the topology of the digital sequential logic circuit is triggered by the clock pulse to synthesize the clock signal with an inverse multiple frequency to the genetic oscillator. The function acts like a frequency divider in electronic circuits which plays a key role in the sequential logic circuit with specific operational frequency. A cascaded genetic logic circuit generating clock pulse signals is proposed. Based on analogous implement of digital sequential logic circuits, genetic sequential logic circuits can be constructed by the proposed approach to generate various clock signals from an oscillation signal.

  17. Sequential weak continuity of null Lagrangians at the boundary

    Czech Academy of Sciences Publication Activity Database

    Kalamajska, A.; Kraemer, S.; Kružík, Martin

    2014-01-01

    Roč. 49, 3/4 (2014), s. 1263-1278 ISSN 0944-2669 R&D Projects: GA ČR GAP201/10/0357 Institutional support: RVO:67985556 Keywords : null Lagrangians * nonhomogeneous nonlinear mappings * sequential weak/in measure continuity Subject RIV: BA - General Mathematics Impact factor: 1.518, year: 2014 http://library.utia.cas.cz/separaty/2013/MTR/kruzik-sequential weak continuity of null lagrangians at the boundary.pdf

  18. Can standard sequential extraction determinations effectively define heavy metal species in superfund site soils?

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Cheryl L.; Williamson, Connie A.; Collins, Wesley K.; Dahlin, David C.

    2001-01-01

    Speciation and distribution of heavy metals in soils controls the degree to which metals and their compounds are mobile, extractable, and plant-available. Consequently, speciation impacts the success of remediation efforts both by defining the relationship of the contaminants with their environment and by guiding development and evaluation of workable remediation strategies. The U.S. Department of Energy, Albany Research Center (Albany, OR), under a two-year interagency project with the U.S. Environmental Protection Agency (EPA), examined the suitability of sequential extraction as a definitive means to determine species of heavy metals in soil samples. Representative soil samples, contaminated with lead, arsenic, and/or chromium, were collected by EPA personnel from two Superfund sites, the National Lead Company site in Pedricktown, NJ, and the Roebling Steel, Inc., site in Florence, NJ. Data derived from Tessier=s standard three-stage sequential-extraction procedure were compared to data from a comprehensive characterization study that combined optical- and scanning-electron microscopy (with energy-dispersive x-ray and wavelength-dispersive x-ray analyses), x-ray diffraction, and chemical analyses. The results show that standard sequential-extraction procedures that were developed for characterizing species of contaminants in river sediments may be unsuitable for sole evaluation of contaminant species in industrial-site materials (particularly those that contain larger particles of the contaminants, encapsulated contaminants, and/or man-made materials such as slags, metals, and plastics). However, each sequential extraction or comprehensive characterization procedure has it=s own strengths and weaknesses. Findings of this study indicate that the use of both approaches, during the early stages of site studies, would be a best practice. The investigation also highlights the fact that an effective speciation study does not simply identify metal contaminants as

  19. Sequential and simultaneous SLAR block adjustment. [spline function analysis for mapping

    Science.gov (United States)

    Leberl, F.

    1975-01-01

    Two sequential methods of planimetric SLAR (Side Looking Airborne Radar) block adjustment, with and without splines, and three simultaneous methods based on the principles of least squares are evaluated. A limited experiment with simulated SLAR images indicates that sequential block formation with splines followed by external interpolative adjustment is superior to the simultaneous methods such as planimetric block adjustment with similarity transformations. The use of the sequential block formation is recommended, since it represents an inexpensive tool for satisfactory point determination from SLAR images.

  20. Device-independent two-party cryptography secure against sequential attacks

    International Nuclear Information System (INIS)

    Kaniewski, Jędrzej; Wehner, Stephanie

    2016-01-01

    The goal of two-party cryptography is to enable two parties, Alice and Bob, to solve common tasks without the need for mutual trust. Examples of such tasks are private access to a database, and secure identification. Quantum communication enables security for all of these problems in the noisy-storage model by sending more signals than the adversary can store in a certain time frame. Here, we initiate the study of device-independent (DI) protocols for two-party cryptography in the noisy-storage model. Specifically, we present a relatively easy to implement protocol for a cryptographic building block known as weak string erasure and prove its security even if the devices used in the protocol are prepared by the dishonest party. DI two-party cryptography is made challenging by the fact that Alice and Bob do not trust each other, which requires new techniques to establish security. We fully analyse the case of memoryless devices (for which sequential attacks are optimal) and the case of sequential attacks for arbitrary devices. The key ingredient of the proof, which might be of independent interest, is an explicit (and tight) relation between the violation of the Clauser–Horne–Shimony–Holt inequality observed by Alice and Bob and uncertainty generated by Alice against Bob who is forced to measure his system before finding out Alice’s setting (guessing with postmeasurement information). In particular, we show that security is possible for arbitrarily small violation. (paper)

  1. Device-independent two-party cryptography secure against sequential attacks

    Science.gov (United States)

    Kaniewski, Jędrzej; Wehner, Stephanie

    2016-05-01

    The goal of two-party cryptography is to enable two parties, Alice and Bob, to solve common tasks without the need for mutual trust. Examples of such tasks are private access to a database, and secure identification. Quantum communication enables security for all of these problems in the noisy-storage model by sending more signals than the adversary can store in a certain time frame. Here, we initiate the study of device-independent (DI) protocols for two-party cryptography in the noisy-storage model. Specifically, we present a relatively easy to implement protocol for a cryptographic building block known as weak string erasure and prove its security even if the devices used in the protocol are prepared by the dishonest party. DI two-party cryptography is made challenging by the fact that Alice and Bob do not trust each other, which requires new techniques to establish security. We fully analyse the case of memoryless devices (for which sequential attacks are optimal) and the case of sequential attacks for arbitrary devices. The key ingredient of the proof, which might be of independent interest, is an explicit (and tight) relation between the violation of the Clauser-Horne-Shimony-Holt inequality observed by Alice and Bob and uncertainty generated by Alice against Bob who is forced to measure his system before finding out Alice’s setting (guessing with postmeasurement information). In particular, we show that security is possible for arbitrarily small violation.

  2. Sequentially solution-processed, nanostructured polymer photovoltaics using selective solvents

    KAUST Repository

    Kim, Do Hwan; Mei, Jianguo; Ayzner, Alexander L.; Schmidt, Kristin; Giri, Gaurav; Appleton, Anthony L.; Toney, Michael F.; Bao, Zhenan

    2014-01-01

    We demonstrate high-performance sequentially solution-processed organic photovoltaics (OPVs) with a power conversion efficiency (PCE) of 5% for blend films using a donor polymer based on the isoindigo-bithiophene repeat unit (PII2T-C10C8) and a fullerene derivative [6,6]-phenyl-C[71]-butyric acid methyl ester (PC71BM). This has been accomplished by systematically controlling the swelling and intermixing processes of the layer with various processing solvents during deposition of the fullerene. We find that among the solvents used for fullerene deposition that primarily swell but do not re-dissolve the polymer underlayer, there were significant microstructural differences between chloro and o-dichlorobenzene solvents (CB and ODCB, respectively). Specifically, we show that the polymer crystallite orientation distribution in films where ODCB was used to cast the fullerene is broad. This indicates that out-of-plane charge transport through a tortuous transport network is relatively efficient due to a large density of inter-grain connections. In contrast, using CB results in primarily edge-on oriented polymer crystallites, which leads to diminished out-of-plane charge transport. We correlate these microstructural differences with photocurrent measurements, which clearly show that casting the fullerene out of ODCB leads to significantly enhanced power conversion efficiencies. Thus, we believe that tuning the processing solvents used to cast the electron acceptor in sequentially-processed devices is a viable way to controllably tune the blend film microstructure. © 2014 The Royal Society of Chemistry.

  3. Exploring Elementary-School Students' Engagement Patterns in a Game-Based Learning Environment

    Science.gov (United States)

    Hsieh, Ya-Hui; Lin, Yi-Chun; Hou, Huei-Tse

    2015-01-01

    Unlike most research, which has primarily examined the players' interest in or attitude toward game-based learning through questionnaires, the purpose of this empirical study is to explore students' engagement patterns by qualitative observation and sequential analysis to visualize and better understand their game-based learning process. We…

  4. Sequential Extraction Versus Comprehensive Characterization of Heavy Metal Species in Brownfield Soils

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Cheryl L.; Williamson, Connie A.; Collins, W. Keith; Dahlin, David C.

    2002-06-01

    The applicability of sequential extraction as a means to determine species of heavy-metals was examined by a study on soil samples from two Superfund sites: the National Lead Company site in Pedricktown, NJ, and the Roebling Steel, Inc., site in Florence, NJ. Data from a standard sequential extraction procedure were compared to those from a comprehensive study that combined optical- and scanning-electron microscopy, X-ray diffraction, and chemical analyses. The study shows that larger particles of contaminants, encapsulated contaminants, and/or man-made materials such as slags, coke, metals, and plastics are subject to incasement, non-selectivity, and redistribution in the sequential extraction process. The results indicate that standard sequential extraction procedures that were developed for characterizing species of contaminants in river sediments may be unsuitable for stand-alone determinative evaluations of contaminant species in industrial-site materials. However, if employed as part of a comprehensive, site-specific characterization study, sequential extraction could be a very useful tool.

  5. Difference in vascular patterns between transosseous-equivalent and transosseous rotator cuff repair.

    Science.gov (United States)

    Urita, Atsushi; Funakoshi, Tadanao; Horie, Tatsunori; Nishida, Mutsumi; Iwasaki, Norimasa

    2017-01-01

    Vascularity is the important factor of biologic healing of the repaired tissue. The purpose of this study was to clarify sequential vascular patterns of repaired rotator cuff by suture techniques. We randomized 21 shoulders in 20 patients undergoing arthroscopic rotator cuff repair into 2 groups: transosseous-equivalent repair (TOE group, n = 10) and transosseous repair (TO group, n = 11). Blood flow in 4 regions inside the cuff (lateral articular, lateral bursal, medial articular, and medial bursal), in the knotless suture anchor in the TOE group, and in the bone tunnel in the TO group was measured using contrast-enhanced ultrasound at 1 month, 2 months, 3 months, and 6 months postoperatively. The sequential vascular pattern inside the repaired rotator cuff was different between groups. The blood flow in the lateral articular area at 1 month, 2 months, and 3 months (P = .002, .005, and .025) and that in the lateral bursal area at 2 months (P = .031) in the TO group were significantly greater than those in the TOE group postoperatively. Blood flow was significantly greater for the bone tunnels in the TO group than for the knotless suture anchor in the TOE group at 1 month and 2 months postoperatively (P = .041 and .009). This study clarified that the sequential vascular pattern inside the repaired rotator cuff depends on the suture technique used. Bone tunnels through the footprint may contribute to biologic healing by increasing blood flow in the repaired rotator cuff. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  6. Imaging Findings of Complex Fibroadenoma of the Breast: Correlation with Pathologic Findings

    Energy Technology Data Exchange (ETDEWEB)

    You, Sun Kyoung; Choi, Bo Bae; Kim, Kyung Hee [Chungnam National University Hospital College of Medicine, Seoul (Korea, Republic of)

    2010-12-15

    The imaging findings of complex fibroadenoma have been rarely reported even though the risk of developing breast carcinoma in a patient with complex fibroadenoma is higher than that for a patient with simple fibroadenoma. We reviewed the imaging features and pathologic findings of complex fibroadenomas. Between April 2003 and April 2010, the mammographic and sonographic findings of five patients with complex fibroadenomas were retrospectively reviewed according to the Breast Imaging Reporting and Data System (BIRADS). The pathologic findings were retrospectively reviewed for all 5 patients. The mammography findings showed masses (3 cases) and asymmetry (1 case). On ultrasonography, complex echo patterns were noted in all the patients, and all the lesions were assigned to BI-RADS category 4, suspicious for abnormality. The complex echoic patterns showed two types: 1) a mixture of a heterogeneous hypoechoic central portion and a fuzzy hyperechoic peripheral area in 2 cases, 2) a mixture of tiny anechoic and hypoehoic lesions in 3 cases. Multiple cystic changes were noted in all the cases on the pathologic analysis. Complex fibroadenomas showed different ultrasonographic findings from simple fibroadenomas such as two types of complex echo patterns, even though the other findings were similar to those of simple fibroadenoma. Cystic changes were noted in all the cases on the pathologic analysis. Awareness of these imaging findings will help us to properly diagnose complex fibroadenoma

  7. Imaging Findings of Complex Fibroadenoma of the Breast: Correlation with Pathologic Findings

    International Nuclear Information System (INIS)

    You, Sun Kyoung; Choi, Bo Bae; Kim, Kyung Hee

    2010-01-01

    The imaging findings of complex fibroadenoma have been rarely reported even though the risk of developing breast carcinoma in a patient with complex fibroadenoma is higher than that for a patient with simple fibroadenoma. We reviewed the imaging features and pathologic findings of complex fibroadenomas. Between April 2003 and April 2010, the mammographic and sonographic findings of five patients with complex fibroadenomas were retrospectively reviewed according to the Breast Imaging Reporting and Data System (BIRADS). The pathologic findings were retrospectively reviewed for all 5 patients. The mammography findings showed masses (3 cases) and asymmetry (1 case). On ultrasonography, complex echo patterns were noted in all the patients, and all the lesions were assigned to BI-RADS category 4, suspicious for abnormality. The complex echoic patterns showed two types: 1) a mixture of a heterogeneous hypoechoic central portion and a fuzzy hyperechoic peripheral area in 2 cases, 2) a mixture of tiny anechoic and hypoehoic lesions in 3 cases. Multiple cystic changes were noted in all the cases on the pathologic analysis. Complex fibroadenomas showed different ultrasonographic findings from simple fibroadenomas such as two types of complex echo patterns, even though the other findings were similar to those of simple fibroadenoma. Cystic changes were noted in all the cases on the pathologic analysis. Awareness of these imaging findings will help us to properly diagnose complex fibroadenoma

  8. Sequential determination of important ecotoxic radionuclides in nuclear waste samples

    International Nuclear Information System (INIS)

    Bilohuscin, J.

    2016-01-01

    In the dissertation thesis we focused on the development and optimization of a sequential determination method for radionuclides 93 Zr, 94 Nb, 99 Tc and 126 Sn, employing extraction chromatography sorbents TEVA (R) Resin and Anion Exchange Resin, supplied by Eichrom Industries. Prior to the attestation of sequential separation of these proposed radionuclides from radioactive waste samples, a unique sequential procedure of 90 Sr, 239 Pu, 241 Am separation from urine matrices was tried, using molecular recognition sorbents of AnaLig (R) series and extraction chromatography sorbent DGA (R) Resin. On these experiments, four various sorbents were continually used for separation, including PreFilter Resin sorbent, which removes interfering organic materials present in raw urine. After the acquisition of positive results of this sequential procedure followed experiments with a 126 Sn separation using TEVA (R) Resin and Anion Exchange Resin sorbents. Radiochemical recoveries obtained from samples of radioactive evaporate concentrates and sludge showed high efficiency of the separation, while values of 126 Sn were under the minimum detectable activities MDA. Activity of 126 Sn was determined after ingrowth of daughter nuclide 126m Sb on HPGe gamma detector, with minimal contamination of gamma interfering radionuclides with decontamination factors (D f ) higher then 1400 for 60 Co and 47000 for 137 Cs. Based on the acquired experiments and results of these separation procedures, a complex method of sequential separation of 93 Zr, 94 Nb, 99 Tc and 126 Sn was proposed, which included optimization steps similar to those used in previous parts of the dissertation work. Application of the sequential separation method for sorbents TEVA (R) Resin and Anion Exchange Resin on real samples of radioactive wastes provided satisfactory results and an economical, time sparing, efficient method. (author)

  9. Organization principles in visual working memory: Evidence from sequential stimulus display.

    Science.gov (United States)

    Gao, Zaifeng; Gao, Qiyang; Tang, Ning; Shui, Rende; Shen, Mowei

    2016-01-01

    Although the mechanisms of visual working memory (VWM) have been studied extensively in recent years, the active property of VWM has received less attention. In the current study, we examined how VWM integrates sequentially presented stimuli by focusing on the role of Gestalt principles, which are important organizing principles in perceptual integration. We manipulated the level of Gestalt cues among three or four sequentially presented objects that were memorized. The Gestalt principle could not emerge unless all the objects appeared together. We distinguished two hypotheses: a perception-alike hypothesis and an encoding-specificity hypothesis. The former predicts that the Gestalt cue will play a role in information integration within VWM; the latter predicts that the Gestalt cue will not operate within VWM. In four experiments, we demonstrated that collinearity (Experiment 1) and closure (Experiment 2) cues significantly improved VWM performance, and this facilitation was not affected by the testing manner (Experiment 3) or by adding extra colors to the memorized objects (Experiment 4). Finally, we re-established the Gestalt cue benefit with similarity cues (Experiment 5). These findings together suggest that VWM realizes and uses potential Gestalt principles within the stored representations, supporting a perception-alike hypothesis. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. A solution for automatic parallelization of sequential assembly code

    Directory of Open Access Journals (Sweden)

    Kovačević Đorđe

    2013-01-01

    Full Text Available Since modern multicore processors can execute existing sequential programs only on a single core, there is a strong need for automatic parallelization of program code. Relying on existing algorithms, this paper describes one new software solution tool for parallelization of sequential assembly code. The main goal of this paper is to develop the parallelizator which reads sequential assembler code and at the output provides parallelized code for MIPS processor with multiple cores. The idea is the following: the parser translates assembler input file to program objects suitable for further processing. After that the static single assignment is done. Based on the data flow graph, the parallelization algorithm separates instructions on different cores. Once sequential code is parallelized by the parallelization algorithm, registers are allocated with the algorithm for linear allocation, and the result at the end of the program is distributed assembler code on each of the cores. In the paper we evaluate the speedup of the matrix multiplication example, which was processed by the parallelizator of assembly code. The result is almost linear speedup of code execution, which increases with the number of cores. The speed up on the two cores is 1.99, while on 16 cores the speed up is 13.88.

  11. Mind-to-mind heteroclinic coordination: Model of sequential episodic memory initiation

    Science.gov (United States)

    Afraimovich, V. S.; Zaks, M. A.; Rabinovich, M. I.

    2018-05-01

    Retrieval of episodic memory is a dynamical process in the large scale brain networks. In social groups, the neural patterns, associated with specific events directly experienced by single members, are encoded, recalled, and shared by all participants. Here, we construct and study the dynamical model for the formation and maintaining of episodic memory in small ensembles of interacting minds. We prove that the unconventional dynamical attractor of this process—the nonsmooth heteroclinic torus—is structurally stable within the Lotka-Volterra-like sets of equations. Dynamics on this torus combines the absence of chaos with asymptotic instability of every separate trajectory; its adequate quantitative characteristics are length-related Lyapunov exponents. Variation of the coupling strength between the participants results in different types of sequential switching between metastable states; we interpret them as stages in formation and modification of the episodic memory.

  12. Documentscape: Intertextuality, Sequentiality & Autonomy at Work

    DEFF Research Database (Denmark)

    Christensen, Lars Rune; Bjørn, Pernille

    2014-01-01

    On the basis of an ethnographic field study, this article introduces the concept of documentscape to the analysis of document-centric work practices. The concept of documentscape refers to the entire ensemble of documents in their mutual intertextual interlocking. Providing empirical data from...... a global software development case, we show how hierarchical structures and sequentiality across the interlocked documents are critical to how actors make sense of the work of others and what to do next in a geographically distributed setting. Furthermore, we found that while each document is created...... as part of a quasi-sequential order, this characteristic does not make the document, as a single entity, into a stable object. Instead, we found that the documents were malleable and dynamic while suspended in intertextual structures. Our concept of documentscape points to how the hierarchical structure...

  13. Sequential inflammatory processes define human progression from M. tuberculosis infection to tuberculosis disease.

    Science.gov (United States)

    Scriba, Thomas J; Penn-Nicholson, Adam; Shankar, Smitha; Hraha, Tom; Thompson, Ethan G; Sterling, David; Nemes, Elisa; Darboe, Fatoumatta; Suliman, Sara; Amon, Lynn M; Mahomed, Hassan; Erasmus, Mzwandile; Whatney, Wendy; Johnson, John L; Boom, W Henry; Hatherill, Mark; Valvo, Joe; De Groote, Mary Ann; Ochsner, Urs A; Aderem, Alan; Hanekom, Willem A; Zak, Daniel E

    2017-11-01

    Our understanding of mechanisms underlying progression from Mycobacterium tuberculosis infection to pulmonary tuberculosis disease in humans remains limited. To define such mechanisms, we followed M. tuberculosis-infected adolescents longitudinally. Blood samples from forty-four adolescents who ultimately developed tuberculosis disease (“progressors”) were compared with those from 106 matched controls, who remained healthy during two years of follow up. We performed longitudinal whole blood transcriptomic analyses by RNA sequencing and plasma proteome analyses using multiplexed slow off-rate modified DNA aptamers. Tuberculosis progression was associated with sequential modulation of immunological processes. Type I/II interferon signalling and complement cascade were elevated 18 months before tuberculosis disease diagnosis, while changes in myeloid inflammation, lymphoid, monocyte and neutrophil gene modules occurred more proximally to tuberculosis disease. Analysis of gene expression in purified T cells also revealed early suppression of Th17 responses in progressors, relative to M. tuberculosis-infected controls. This was confirmed in an independent adult cohort who received BCG re-vaccination; transcript expression of interferon response genes in blood prior to BCG administration was associated with suppression of IL-17 expression by BCG-specific CD4 T cells 3 weeks post-vaccination. Our findings provide a timeline to the different immunological stages of disease progression which comprise sequential inflammatory dynamics and immune alterations that precede disease manifestations and diagnosis of tuberculosis disease. These findings have important implications for developing diagnostics, vaccination and host-directed therapies for tuberculosis. Clincialtrials.gov, NCT01119521.

  14. Sequential series for nuclear reactions

    International Nuclear Information System (INIS)

    Izumo, Ko

    1975-01-01

    A new time-dependent treatment of nuclear reactions is given, in which the wave function of compound nucleus is expanded by a sequential series of the reaction processes. The wave functions of the sequential series form another complete set of compound nucleus at the limit Δt→0. It is pointed out that the wave function is characterized by the quantities: the number of degrees of freedom of motion n, the period of the motion (Poincare cycle) tsub(n), the delay time t sub(nμ) and the relaxation time tausub(n) to the equilibrium of compound nucleus, instead of the usual quantum number lambda, the energy eigenvalue Esub(lambda) and the total width GAMMAsub(lambda) of resonance levels, respectively. The transition matrix elements and the yields of nuclear reactions also become the functions of time given by the Fourier transform of the usual ones. The Poincare cycles of compound nuclei are compared with the observed correlations among resonance levels, which are about 10 -17 --10 -16 sec for medium and heavy nuclei and about 10 -20 sec for the intermediate resonances. (auth.)

  15. Evaluation of solitary pulmonary nodules by integrated PET/CT: improved accuracy by FDG uptake pattern and CT findings

    International Nuclear Information System (INIS)

    Joon Young Choi; Kyung Soo Lee; O Jung Kwon; Young Mog Shim; Kyung-Han Lee; Yong Choi; Yearn Seong Choe; Byung-Tae Kim

    2004-01-01

    Objective: FDG PET is useful to differentiate malignancy from benign lesions in the evaluation of solitary pulmonary nodules (SPNs). However, FDG PET showed false positive results in benign inflammatory lesions such as tuberculosis and organizing pneumonia. Furthermore, malignant tumors such as adenocarcinoma (AC) with bronchioloalveolar carcinoma (BAC) type had lower FDG uptake than other cell types of non-small cell lung cancer. We investigated whether FDG uptake pattern and image findings of CT for attenuation correction could improve accuracy for evaluating SPNs over SUV in integrated PET/CT imaging using FDG. Methods: Forty patients (M:F = 23:17, mean age 58.2±9.4 yrs) with non-calcified SPNs (diameter on CT 30 mm, no significant mediastinal node enlargement, no atelectasis) were included. All subjects underwent integrated PET/CT imaging using FDG. One nuclear medicine physician and 1 chest radiologist interpreted the PET and non-contrast CT images for attenuation correction, respectively. On PET images, maximum SUV of SPN was acquired, and FDG uptake pattern was categorized as diffusely increased or heterogeneously increased with upper threshold of window setting adjusted to maximum SUV of each nodule. A radiologist interpreted SPNs as benign or malignant based on CT images with lung and mediastinai window settings blinded to PET findings. Results: On pathological exam, 30 SPNs were confirmed to be malignant (11 AC with non-BAC type, 8 AC with BAC type, 8 squamous cell carcinoma, 1 adenosquamous cell carcinoma, 1 neuroendocrine carcinoma, 1 large cell carcinoma), and 10 were benign (4 tuberculosis, 3 organizing pneumonia, 2 sclerosing pneumocytoma, 1 non-specific inflammation). All 5 nodules with max SUV 7.0 except one with tuberculoma had malignancy. When only nodules with diffusely increased uptake were considered malignant in indeterminate group with max SUV of 4.0 to 7.0, PET could diagnose 5 of 9 malignant nodules with one false positive nodule. In 6 of

  16. Sequential Change-Point Detection via Online Convex Optimization

    Directory of Open Access Journals (Sweden)

    Yang Cao

    2018-02-01

    Full Text Available Sequential change-point detection when the distribution parameters are unknown is a fundamental problem in statistics and machine learning. When the post-change parameters are unknown, we consider a set of detection procedures based on sequential likelihood ratios with non-anticipating estimators constructed using online convex optimization algorithms such as online mirror descent, which provides a more versatile approach to tackling complex situations where recursive maximum likelihood estimators cannot be found. When the underlying distributions belong to a exponential family and the estimators satisfy the logarithm regret property, we show that this approach is nearly second-order asymptotically optimal. This means that the upper bound for the false alarm rate of the algorithm (measured by the average-run-length meets the lower bound asymptotically up to a log-log factor when the threshold tends to infinity. Our proof is achieved by making a connection between sequential change-point and online convex optimization and leveraging the logarithmic regret bound property of online mirror descent algorithm. Numerical and real data examples validate our theory.

  17. Sequential decoders for large MIMO systems

    KAUST Repository

    Ali, Konpal S.; Abediseid, Walid; Alouini, Mohamed-Slim

    2014-01-01

    the Sequential Decoder using the Fano Algorithm for large MIMO systems. A parameter called the bias is varied to attain different performance-complexity trade-offs. Low values of the bias result in excellent performance but at the expense of high complexity

  18. Comment on: "Cell Therapy for Heart Disease: Trial Sequential Analyses of Two Cochrane Reviews"

    DEFF Research Database (Denmark)

    Castellini, Greta; Nielsen, Emil Eik; Gluud, Christian

    2017-01-01

    Trial Sequential Analysis is a frequentist method to help researchers control the risks of random errors in meta-analyses (1). Fisher and colleagues used Trial Sequential Analysis on cell therapy for heart diseases (2). The present article discusses the usefulness of Trial Sequential Analysis and...

  19. Exploiting an automated microfluidic hydrodynamic sequential injection system for determination of phosphate.

    Science.gov (United States)

    Khongpet, Wanpen; Pencharee, Somkid; Puangpila, Chanida; Kradtap Hartwell, Supaporn; Lapanantnoppakhun, Somchai; Jakmunee, Jaroon

    2018-01-15

    A microfluidic hydrodynamic sequential injection (μHSI) spectrophotometric system was designed and fabricated. The system was built by laser engraving a manifold pattern on an acrylic block and sealing with another flat acrylic plate to form a microfluidic channel platform. The platform was incorporated with small solenoid valves to obtain a portable setup for programmable control of the liquid flow into the channel according to the HSI principle. The system was demonstrated for the determination of phosphate using a molybdenum blue method. An ascorbic acid, standard or sample, and acidic molybdate solutions were sequentially aspirated to fill the channel forming a stack zone before flowing to the detector. Under the optimum condition, a linear calibration graph in the range of 0.1-6mg P L -1 was obtained. The detection limit was 0.1mgL -1 . The system is compact (5.0mm thick, 80mm wide × 140mm long), durable, portable, cost-effective, and consumes little amount of chemicals (83μL each of molybdate and ascorbic acid, 133μL of the sample solution and 1.7mL of water carrier/run). It was applied for the determination of phosphate content in extracted soil samples. The percent recoveries of the analysis were obtained in the range of 91.2-107.3. The results obtained agreed well with those of the batch spectrophotometric method. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. An open-label, sequential, dose-finding study of peginesatide for the maintenance treatment of anemia in chronic hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Besarab Anatole

    2012-08-01

    Full Text Available Abstract Background Peginesatide is a peptide-based erythropoiesis-stimulating agent that was designed and engineered to stimulate specifically the erythropoietin receptor dimer that governs erythropoiesis. The primary objective of this phase 2 dose-finding study was to determine the once-monthly peginesatide dosing strategy that would maintain hemoglobin within ±1.0 g/dL of baseline values after conversion from epoetin alfa; the safety of peginesatide was evaluated concurrently. Methods Chronic hemodialysis patients on stable regimens of epoetin alfa were sequentially assigned to cohorts that differed on (1 how the peginesatide starting dose was determined (using a single epoetin alfa–to-peginesatide dose conversion ratio or a tiered, weight-based or absolute-dose conversion table and on (2 whether or not a 1-week erythropoiesis-stimulating agent-free interval was used. Peginesatide doses were titrated to maintain hemoglobin levels within ±1.0 g/dL from baseline. Results A total of 164 patients were enrolled and received intravenous peginesatide every 4 weeks for up to 6 doses; the duration of the study including follow-up was ≤29 weeks. Overall, the proportion of patients with hemoglobin levels within ±1.0 g/dL of baseline increased over the course of the study from 39% (Weeks 2–13 to 54% (Weeks 18–25. Cohorts that used tiered dose conversion tables trended towards having more stable peginesatide doses than did those cohorts that used a single dose conversion ratio. Moreover, cohorts that used an erythropoiesis-stimulating agent-free interval did not have the substantial initial increase in hemoglobin levels that was seen in those cohorts that did not use such an interval. In this study, the safety profile of peginesatide was consistent with those of marketed erythropoiesis-stimulating agents. Conclusions The results of this study were used to guide the dosing regimens used subsequently in phase 3 studies. Once

  1. Determination of feedback in judo by means of T-patterns

    Directory of Open Access Journals (Sweden)

    Iván Prieto Lage

    2014-03-01

    Full Text Available The aim of this research was to propose methodological changes in the teaching-learning process of the judo technique Deashi-harai, pointing out the most frequent technical errors committed during its performance and also its action sequences. We carried out an observational study with the participation of fifty novice judokas at the University of Vigo. We recorded them while performing the Deashi-harai technique after a previous training of four months. Data obtained were evaluated using descriptive statistics and T-patterns analysis. Thus, we indentified: a some typical inaccuracies during the technique execution and b a number of chained errors affecting the imbalance of the body, the position of the right foot, the sweeping action and the action of the arms. These findings allowed us to suggest some motor tasks to correct the identified inaccuracies, the sequential actions to ensure the success of the execution and several recommendations for the proper use of the feedback.

  2. Automatic synthesis of sequential control schemes

    International Nuclear Information System (INIS)

    Klein, I.

    1993-01-01

    Of all hard- and software developed for industrial control purposes, the majority is devoted to sequential, or binary valued, control and only a minor part to classical linear control. Typically, the sequential parts of the controller are invoked during startup and shut-down to bring the system into its normal operating region and into some safe standby region, respectively. Despite its importance, fairly little theoretical research has been devoted to this area, and sequential control programs are therefore still created manually without much theoretical support to obtain a systematic approach. We propose a method to create sequential control programs automatically. The main ideas is to spend some effort off-line modelling the plant, and from this model generate the control strategy, that is the plan. The plant is modelled using action structures, thereby concentrating on the actions instead of the states of the plant. In general the planning problem shows exponential complexity in the number of state variables. However, by focusing on the actions, we can identify problem classes as well as algorithms such that the planning complexity is reduced to polynomial complexity. We prove that these algorithms are sound, i.e., the generated solution will solve the stated problem, and complete, i.e., if the algorithms fail, then no solution exists. The algorithms generate a plan as a set of actions and a partial order on this set specifying the execution order. The generated plant is proven to be minimal and maximally parallel. For a larger class of problems we propose a method to split the original problem into a number of simple problems that can each be solved using one of the presented algorithms. It is also shown how a plan can be translated into a GRAFCET chart, and to illustrate these ideas we have implemented a planing tool, i.e., a system that is able to automatically create control schemes. Such a tool can of course also be used on-line if it is fast enough. This

  3. Fault detection in multiply-redundant measurement systems via sequential testing

    International Nuclear Information System (INIS)

    Ray, A.

    1988-01-01

    The theory and application of a sequential test procedure for fault detection and isolation. The test procedure is suited for development of intelligent instrumentation in strategic processes like aircraft and nuclear plants where redundant measurements are usually available for individual critical variables. The test procedure consists of: (1) a generic redundancy management procedure which is essentially independent of the fault detection strategy and measurement noise statistics, and (2) a modified version of sequential probability ratio test algorithm for fault detection and isolation, which functions within the framework of this redundancy management procedure. The sequential test procedure is suitable for real-time applications using commercially available microcomputers and its efficacy has been verified by online fault detection in an operating nuclear reactor. 15 references

  4. The role of sequential chemoradiation for local advanced oropharyngeal carcinoma

    International Nuclear Information System (INIS)

    Masterson, Liam; Tanweer, Faiz

    2013-01-01

    This study aims to assess survival, prognostic indicators, and pattern of failure for advanced oropharyngeal cancer treated by induction chemotherapy followed by concomitant chemoradiation (sequential CRT). A retrospective review of 80 consecutive patients who underwent chemoradiation [doublet cisplatin and 5-fluorouracil (PF)] for local advanced oropharyngeal carcinoma at a tertiary center from March 2003 to July 2008 is reported. Seven studies utilizing a similar protocol were reviewed, and all outcomes are collated. At a median follow-up of 32 months, the 3-year overall survival was 75%. Tumor size (p<0.001), age at presentation (p<0.002), and failure to complete the full course of induction chemotherapy (p<0.01) were all found to be significant factors affecting survival. Induction chemotherapy followed by concomitant chemoradiation utilizing doublet PF is an effective treatment for local advanced oropharyngeal carcinoma. At present, the addition of a taxane to the PF regimen cannot be assumed to provide benefit until further evidence emerges from a representative controlled trial. (author)

  5. Exploring the Learner's Knowledge Construction and Cognitive Patterns of Different Asynchronous Platforms: Comparison of an Online Discussion Forum and Facebook

    Science.gov (United States)

    Hou, Huei-Tse; Wang, Shu-Ming; Lin, Peng-Chun; Chang, Kuo-En

    2015-01-01

    The primary purpose of this study is to explore the knowledge construction behaviour and cognitive patterns involved in students' online discussion using online forum and Facebook (FB). This study employed quantitative content analysis and lag sequential analysis to examine the content and behavioural patterns of 50 students from a private…

  6. Sequential designs for sensitivity analysis of functional inputs in computer experiments

    International Nuclear Information System (INIS)

    Fruth, J.; Roustant, O.; Kuhnt, S.

    2015-01-01

    Computer experiments are nowadays commonly used to analyze industrial processes aiming at achieving a wanted outcome. Sensitivity analysis plays an important role in exploring the actual impact of adjustable parameters on the response variable. In this work we focus on sensitivity analysis of a scalar-valued output of a time-consuming computer code depending on scalar and functional input parameters. We investigate a sequential methodology, based on piecewise constant functions and sequential bifurcation, which is both economical and fully interpretable. The new approach is applied to a sheet metal forming problem in three sequential steps, resulting in new insights into the behavior of the forming process over time. - Highlights: • Sensitivity analysis method for functional and scalar inputs is presented. • We focus on the discovery of most influential parts of the functional domain. • We investigate economical sequential methodology based on piecewise constant functions. • Normalized sensitivity indices are introduced and investigated theoretically. • Successful application to sheet metal forming on two functional inputs

  7. On the origin of reproducible sequential activity in neural circuits

    Science.gov (United States)

    Afraimovich, V. S.; Zhigulin, V. P.; Rabinovich, M. I.

    2004-12-01

    Robustness and reproducibility of sequential spatio-temporal responses is an essential feature of many neural circuits in sensory and motor systems of animals. The most common mathematical images of dynamical regimes in neural systems are fixed points, limit cycles, chaotic attractors, and continuous attractors (attractive manifolds of neutrally stable fixed points). These are not suitable for the description of reproducible transient sequential neural dynamics. In this paper we present the concept of a stable heteroclinic sequence (SHS), which is not an attractor. SHS opens the way for understanding and modeling of transient sequential activity in neural circuits. We show that this new mathematical object can be used to describe robust and reproducible sequential neural dynamics. Using the framework of a generalized high-dimensional Lotka-Volterra model, that describes the dynamics of firing rates in an inhibitory network, we present analytical results on the existence of the SHS in the phase space of the network. With the help of numerical simulations we confirm its robustness in presence of noise in spite of the transient nature of the corresponding trajectories. Finally, by referring to several recent neurobiological experiments, we discuss possible applications of this new concept to several problems in neuroscience.

  8. Sequential spatial processes for image analysis

    NARCIS (Netherlands)

    M.N.M. van Lieshout (Marie-Colette); V. Capasso

    2009-01-01

    htmlabstractWe give a brief introduction to sequential spatial processes. We discuss their definition, formulate a Markov property, and indicate why such processes are natural tools in tackling high level vision problems. We focus on the problem of tracking a variable number of moving objects

  9. Sequential models for coarsening and missingness

    NARCIS (Netherlands)

    Gill, R.D.; Robins, J.M.

    1997-01-01

    In a companion paper we described what intuitively would seem to be the most general possible way to generate Coarsening at Random mechanisms a sequential procedure called randomized monotone coarsening Counterexamples showed that CAR mechanisms exist which cannot be represented in this way Here we

  10. Program completion of a web-based tailored lifestyle intervention for adults: differences between a sequential and a simultaneous approach.

    Science.gov (United States)

    Schulz, Daniela N; Schneider, Francine; de Vries, Hein; van Osch, Liesbeth A D M; van Nierop, Peter W M; Kremers, Stef P J

    2012-03-08

    Unhealthy lifestyle behaviors often co-occur and are related to chronic diseases. One effective method to change multiple lifestyle behaviors is web-based computer tailoring. Dropout from Internet interventions, however, is rather high, and it is challenging to retain participants in web-based tailored programs, especially programs targeting multiple behaviors. To date, it is unknown how much information people can handle in one session while taking part in a multiple behavior change intervention, which could be presented either sequentially (one behavior at a time) or simultaneously (all behaviors at once). The first objective was to compare dropout rates of 2 computer-tailored interventions: a sequential and a simultaneous strategy. The second objective was to assess which personal characteristics are associated with completion rates of the 2 interventions. Using an RCT design, demographics, health status, physical activity, vegetable consumption, fruit consumption, alcohol intake, and smoking were self-assessed through web-based questionnaires among 3473 adults, recruited through Regional Health Authorities in the Netherlands in the autumn of 2009. First, a health risk appraisal was offered, indicating whether respondents were meeting the 5 national health guidelines. Second, psychosocial determinants of the lifestyle behaviors were assessed and personal advice was provided, about one or more lifestyle behaviors. Our findings indicate a high non-completion rate for both types of intervention (71.0%; n = 2167), with more incompletes in the simultaneous intervention (77.1%; n = 1169) than in the sequential intervention (65.0%; n = 998). In both conditions, discontinuation was predicted by a lower age (sequential condition: OR = 1.04; P simultaneous condition: OR = 1.04; P sequential condition: OR = 0.86; P = .01; CI = 0.76-0.97; simultaneous condition: OR = 0.49; P sequential intervention, being male (OR = 1.27; P = .04; CI = 1.01-1.59) also predicted dropout

  11. Sequential bayes estimation algorithm with cubic splines on uniform meshes

    International Nuclear Information System (INIS)

    Hossfeld, F.; Mika, K.; Plesser-Walk, E.

    1975-11-01

    After outlining the principles of some recent developments in parameter estimation, a sequential numerical algorithm for generalized curve-fitting applications is presented combining results from statistical estimation concepts and spline analysis. Due to its recursive nature, the algorithm can be used most efficiently in online experimentation. Using computer-sumulated and experimental data, the efficiency and the flexibility of this sequential estimation procedure is extensively demonstrated. (orig.) [de

  12. The sequential trauma score - a new instrument for the sequential mortality prediction in major trauma*

    Directory of Open Access Journals (Sweden)

    Huber-Wagner S

    2010-05-01

    Full Text Available Abstract Background There are several well established scores for the assessment of the prognosis of major trauma patients that all have in common that they can be calculated at the earliest during intensive care unit stay. We intended to develop a sequential trauma score (STS that allows prognosis at several early stages based on the information that is available at a particular time. Study design In a retrospective, multicenter study using data derived from the Trauma Registry of the German Trauma Society (2002-2006, we identified the most relevant prognostic factors from the patients basic data (P, prehospital phase (A, early (B1, and late (B2 trauma room phase. Univariate and logistic regression models as well as score quality criteria and the explanatory power have been calculated. Results A total of 2,354 patients with complete data were identified. From the patients basic data (P, logistic regression showed that age was a significant predictor of survival (AUCmodel p, area under the curve = 0.63. Logistic regression of the prehospital data (A showed that blood pressure, pulse rate, Glasgow coma scale (GCS, and anisocoria were significant predictors (AUCmodel A = 0.76; AUCmodel P + A = 0.82. Logistic regression of the early trauma room phase (B1 showed that peripheral oxygen saturation, GCS, anisocoria, base excess, and thromboplastin time to be significant predictors of survival (AUCmodel B1 = 0.78; AUCmodel P +A + B1 = 0.85. Multivariate analysis of the late trauma room phase (B2 detected cardiac massage, abbreviated injury score (AIS of the head ≥ 3, the maximum AIS, the need for transfusion or massive blood transfusion, to be the most important predictors (AUCmodel B2 = 0.84; AUCfinal model P + A + B1 + B2 = 0.90. The explanatory power - a tool for the assessment of the relative impact of each segment to mortality - is 25% for P, 7% for A, 17% for B1 and 51% for B2. A spreadsheet for the easy calculation of the sequential trauma

  13. Sequential Foreign Investments, Regional Technology Platforms and the Evolution of Japanese Multinationals in East Asia

    OpenAIRE

    Song, Jaeyong

    2001-01-01

    IVABSTRACTIn this paper, we investigate the firm-level mechanisms that underlie the sequential foreign direct investment (FDI) decisions of multinational corporations (MNCs). To understand inter-firm heterogeneity in the sequential FDI behaviors of MNCs, we develop a firm capability-based model of sequential FDI decisions. In the setting of Japanese electronics MNCs in East Asia, we empirically examine how prior investments in firm capabilities affect sequential investments into existingprodu...

  14. Differences in Sequential Eye Movement Behavior between Taiwanese and American Viewers

    Directory of Open Access Journals (Sweden)

    Yen Ju eLee

    2016-05-01

    Full Text Available Knowledge of how information is sought in the visual world is useful for predicting and simulating human behavior. Taiwanese participants and American participants were instructed to judge the facial expression of a focal face that was flanked horizontally by other faces while their eye movements were monitored. The Taiwanese participants distributed their eye fixations more widely than American participants, started to look away from the focal face earlier than American participants, and spent a higher percentage of time looking at the flanking faces. Eye movement transition matrices also provided evidence that Taiwanese participants continually, and systematically shifted gaze between focal and flanking faces. Eye movement patterns were less systematic and less prevalent in American participants. This suggests that both cultures utilized different attention allocation strategies. The results highlight the importance of determining sequential eye movement statistics in cross-cultural research on the utilization of visual context.

  15. A fast and accurate online sequential learning algorithm for feedforward networks.

    Science.gov (United States)

    Liang, Nan-Ying; Huang, Guang-Bin; Saratchandran, P; Sundararajan, N

    2006-11-01

    In this paper, we develop an online sequential learning algorithm for single hidden layer feedforward networks (SLFNs) with additive or radial basis function (RBF) hidden nodes in a unified framework. The algorithm is referred to as online sequential extreme learning machine (OS-ELM) and can learn data one-by-one or chunk-by-chunk (a block of data) with fixed or varying chunk size. The activation functions for additive nodes in OS-ELM can be any bounded nonconstant piecewise continuous functions and the activation functions for RBF nodes can be any integrable piecewise continuous functions. In OS-ELM, the parameters of hidden nodes (the input weights and biases of additive nodes or the centers and impact factors of RBF nodes) are randomly selected and the output weights are analytically determined based on the sequentially arriving data. The algorithm uses the ideas of ELM of Huang et al. developed for batch learning which has been shown to be extremely fast with generalization performance better than other batch training methods. Apart from selecting the number of hidden nodes, no other control parameters have to be manually chosen. Detailed performance comparison of OS-ELM is done with other popular sequential learning algorithms on benchmark problems drawn from the regression, classification and time series prediction areas. The results show that the OS-ELM is faster than the other sequential algorithms and produces better generalization performance.

  16. Sequential spatial processes for image analysis

    NARCIS (Netherlands)

    Lieshout, van M.N.M.; Capasso, V.

    2009-01-01

    We give a brief introduction to sequential spatial processes. We discuss their definition, formulate a Markov property, and indicate why such processes are natural tools in tackling high level vision problems. We focus on the problem of tracking a variable number of moving objects through a video

  17. Frequency guided methods for demodulation of a single fringe pattern.

    Science.gov (United States)

    Wang, Haixia; Kemao, Qian

    2009-08-17

    Phase demodulation from a single fringe pattern is a challenging task but of interest. A frequency-guided regularized phase tracker and a frequency-guided sequential demodulation method with Levenberg-Marquardt optimization are proposed to demodulate a single fringe pattern. Demodulation path guided by the local frequency from the highest to the lowest is applied in both methods. Since critical points have low local frequency values, they are processed last so that the spurious sign problem caused by these points is avoided. These two methods can be considered as alternatives to the effective fringe follower regularized phase tracker. Demodulation results from one computer-simulated and two experimental fringe patterns using the proposed methods will be demonstrated. (c) 2009 Optical Society of America

  18. Polarization control of direct (non-sequential) two-photon double ionization of He

    International Nuclear Information System (INIS)

    Pronin, E A; Manakov, N L; Marmo, S I; Starace, Anthony F

    2007-01-01

    An ab initio parametrization of the doubly-differential cross section (DDCS) for two-photon double ionization (TPDI) from an s 2 subshell of an atom in a 1 S 0 -state is presented. Analysis of the elliptic dichroism (ED) effect in the DDCS for TPDI of He and its comparison with the same effect in the concurrent process of sequential double ionization shows their qualitative and quantitative differences, thus providing a means to control and to distinguish sequential and non-sequential processes by measuring the relative ED parameter

  19. A Bayesian sequential design using alpha spending function to control type I error.

    Science.gov (United States)

    Zhu, Han; Yu, Qingzhao

    2017-10-01

    We propose in this article a Bayesian sequential design using alpha spending functions to control the overall type I error in phase III clinical trials. We provide algorithms to calculate critical values, power, and sample sizes for the proposed design. Sensitivity analysis is implemented to check the effects from different prior distributions, and conservative priors are recommended. We compare the power and actual sample sizes of the proposed Bayesian sequential design with different alpha spending functions through simulations. We also compare the power of the proposed method with frequentist sequential design using the same alpha spending function. Simulations show that, at the same sample size, the proposed method provides larger power than the corresponding frequentist sequential design. It also has larger power than traditional Bayesian sequential design which sets equal critical values for all interim analyses. When compared with other alpha spending functions, O'Brien-Fleming alpha spending function has the largest power and is the most conservative in terms that at the same sample size, the null hypothesis is the least likely to be rejected at early stage of clinical trials. And finally, we show that adding a step of stop for futility in the Bayesian sequential design can reduce the overall type I error and reduce the actual sample sizes.

  20. Sequential ensemble-based optimal design for parameter estimation: SEQUENTIAL ENSEMBLE-BASED OPTIMAL DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    Man, Jun [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Zhang, Jiangjiang [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Li, Weixuan [Pacific Northwest National Laboratory, Richland Washington USA; Zeng, Lingzao [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Wu, Laosheng [Department of Environmental Sciences, University of California, Riverside California USA

    2016-10-01

    The ensemble Kalman filter (EnKF) has been widely used in parameter estimation for hydrological models. The focus of most previous studies was to develop more efficient analysis (estimation) algorithms. On the other hand, it is intuitively understandable that a well-designed sampling (data-collection) strategy should provide more informative measurements and subsequently improve the parameter estimation. In this work, a Sequential Ensemble-based Optimal Design (SEOD) method, coupled with EnKF, information theory and sequential optimal design, is proposed to improve the performance of parameter estimation. Based on the first-order and second-order statistics, different information metrics including the Shannon entropy difference (SD), degrees of freedom for signal (DFS) and relative entropy (RE) are used to design the optimal sampling strategy, respectively. The effectiveness of the proposed method is illustrated by synthetic one-dimensional and two-dimensional unsaturated flow case studies. It is shown that the designed sampling strategies can provide more accurate parameter estimation and state prediction compared with conventional sampling strategies. Optimal sampling designs based on various information metrics perform similarly in our cases. The effect of ensemble size on the optimal design is also investigated. Overall, larger ensemble size improves the parameter estimation and convergence of optimal sampling strategy. Although the proposed method is applied to unsaturated flow problems in this study, it can be equally applied in any other hydrological problems.

  1. The pursuit of balance in sequential randomized trials

    Directory of Open Access Journals (Sweden)

    Raymond P. Guiteras

    2016-06-01

    Full Text Available In many randomized trials, subjects enter the sample sequentially. Because the covariates for all units are not known in advance, standard methods of stratification do not apply. We describe and assess the method of DA-optimal sequential allocation (Atkinson, 1982 for balancing stratification covariates across treatment arms. We provide simulation evidence that the method can provide substantial improvements in precision over commonly employed alternatives. We also describe our experience implementing the method in a field trial of a clean water and handwashing intervention in Dhaka, Bangladesh, the first time the method has been used. We provide advice and software for future researchers.

  2. Event-shape analysis: Sequential versus simultaneous multifragment emission

    International Nuclear Information System (INIS)

    Cebra, D.A.; Howden, S.; Karn, J.; Nadasen, A.; Ogilvie, C.A.; Vander Molen, A.; Westfall, G.D.; Wilson, W.K.; Winfield, J.S.; Norbeck, E.

    1990-01-01

    The Michigan State University 4π array has been used to select central-impact-parameter events from the reaction 40 Ar+ 51 V at incident energies from 35 to 85 MeV/nucleon. The event shape in momentum space is an observable which is shown to be sensitive to the dynamics of the fragmentation process. A comparison of the experimental event-shape distribution to sequential- and simultaneous-decay predictions suggests that a transition in the breakup process may have occurred. At 35 MeV/nucleon, a sequential-decay simulation reproduces the data. For the higher energies, the experimental distributions fall between the two contrasting predictions

  3. Sequential approach to Colombeau's theory of generalized functions

    International Nuclear Information System (INIS)

    Todorov, T.D.

    1987-07-01

    J.F. Colombeau's generalized functions are constructed as equivalence classes of the elements of a specially chosen ultrapower of the class of the C ∞ -functions. The elements of this ultrapower are considered as sequences of C ∞ -functions, so in a sense, the sequential construction presented here refers to the original Colombeau theory just as, for example, the Mikusinski sequential approach to the distribution theory refers to the original Schwartz theory of distributions. The paper could be used as an elementary introduction to the Colombeau theory in which recently a solution was found to the problem of multiplication of Schwartz distributions. (author). Refs

  4. Configural and component processing in simultaneous and sequential lineup procedures

    OpenAIRE

    Flowe, HD; Smith, HMJ; Karoğlu, N; Onwuegbusi, TO; Rai, L

    2015-01-01

    Configural processing supports accurate face recognition, yet it has never been examined within the context of criminal identification lineups. We tested, using the inversion paradigm, the role of configural processing in lineups. Recent research has found that face discrimination accuracy in lineups is better in a simultaneous compared to a sequential lineup procedure. Therefore, we compared configural processing in simultaneous and sequential lineups to examine whether there are differences...

  5. Sequential injection of domain walls into ferroelectrics at different bias voltages: Paving the way for “domain wall memristors”

    Energy Technology Data Exchange (ETDEWEB)

    Whyte, J. R.; McQuaid, R. G. P.; Einsle, J. F.; Gregg, J. M., E-mail: m.gregg@qub.ac.uk [Centre for Nanostructured Media (CNM), School of Maths and Physics, Queen' s University Belfast, University Road, Belfast BT7 1NN (United Kingdom); Ashcroft, C. M. [Centre for Nanostructured Media (CNM), School of Maths and Physics, Queen' s University Belfast, University Road, Belfast BT7 1NN (United Kingdom); Department of Physics, Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Canalias, C. [Department of Applied Physics, Royal Institute of Technology, Roslagstullsbacken 21, 10691 Stockholm (Sweden); Gruverman, A. [Department of Physics and Astronomy, University of Nebraska Lincoln, Nebraska 68588–0299 (United States)

    2014-08-14

    Simple meso-scale capacitor structures have been made by incorporating thin (∼300 nm) single crystal lamellae of KTiOPO{sub 4} (KTP) between two coplanar Pt electrodes. The influence that either patterned protrusions in the electrodes or focused ion beam milled holes in the KTP have on the nucleation of reverse domains during switching was mapped using piezoresponse force microscopy imaging. The objective was to assess whether or not variations in the magnitude of field enhancement at localised “hot-spots,” caused by such patterning, could be used to both control the exact locations and bias voltages at which nucleation events occurred. It was found that both the patterning of electrodes and the milling of various hole geometries into the KTP could allow controlled sequential injection of domain wall pairs at different bias voltages; this capability could have implications for the design and operation of domain wall electronic devices, such as memristors, in the future.

  6. Audio-visual speech perception in prelingually deafened Japanese children following sequential bilateral cochlear implantation.

    Science.gov (United States)

    Yamamoto, Ryosuke; Naito, Yasushi; Tona, Risa; Moroto, Saburo; Tamaya, Rinko; Fujiwara, Keizo; Shinohara, Shogo; Takebayashi, Shinji; Kikuchi, Masahiro; Michida, Tetsuhiko

    2017-11-01

    An effect of audio-visual (AV) integration is observed when the auditory and visual stimuli are incongruent (the McGurk effect). In general, AV integration is helpful especially in subjects wearing hearing aids or cochlear implants (CIs). However, the influence of AV integration on spoken word recognition in individuals with bilateral CIs (Bi-CIs) has not been fully investigated so far. In this study, we investigated AV integration in children with Bi-CIs. The study sample included thirty one prelingually deafened children who underwent sequential bilateral cochlear implantation. We assessed their responses to congruent and incongruent AV stimuli with three CI-listening modes: only the 1st CI, only the 2nd CI, and Bi-CIs. The responses were assessed in the whole group as well as in two sub-groups: a proficient group (syllable intelligibility ≥80% with the 1st CI) and a non-proficient group (syllable intelligibility effect in each of the three CI-listening modes. AV integration responses were observed in a subset of incongruent AV stimuli, and the patterns observed with the 1st CI and with Bi-CIs were similar. In the proficient group, the responses with the 2nd CI were not significantly different from those with the 1st CI whereas in the non-proficient group the responses with the 2nd CI were driven by visual stimuli more than those with the 1st CI. Our results suggested that prelingually deafened Japanese children who underwent sequential bilateral cochlear implantation exhibit AV integration abilities, both in monaural listening as well as in binaural listening. We also observed a higher influence of visual stimuli on speech perception with the 2nd CI in the non-proficient group, suggesting that Bi-CIs listeners with poorer speech recognition rely on visual information more compared to the proficient subjects to compensate for poorer auditory input. Nevertheless, poorer quality auditory input with the 2nd CI did not interfere with AV integration with binaural

  7. Discovering significant evolution patterns from satellite image time series.

    Science.gov (United States)

    Petitjean, François; Masseglia, Florent; Gançarski, Pierre; Forestier, Germain

    2011-12-01

    Satellite Image Time Series (SITS) provide us with precious information on land cover evolution. By studying these series of images we can both understand the changes of specific areas and discover global phenomena that spread over larger areas. Changes that can occur throughout the sensing time can spread over very long periods and may have different start time and end time depending on the location, which complicates the mining and the analysis of series of images. This work focuses on frequent sequential pattern mining (FSPM) methods, since this family of methods fits the above-mentioned issues. This family of methods consists of finding the most frequent evolution behaviors, and is actually able to extract long-term changes as well as short term ones, whenever the change may start and end. However, applying FSPM methods to SITS implies confronting two main challenges, related to the characteristics of SITS and the domain's constraints. First, satellite images associate multiple measures with a single pixel (the radiometric levels of different wavelengths corresponding to infra-red, red, etc.), which makes the search space multi-dimensional and thus requires specific mining algorithms. Furthermore, the non evolving regions, which are the vast majority and overwhelm the evolving ones, challenge the discovery of these patterns. We propose a SITS mining framework that enables discovery of these patterns despite these constraints and characteristics. Our proposal is inspired from FSPM and provides a relevant visualization principle. Experiments carried out on 35 images sensed over 20 years show the proposed approach makes it possible to extract relevant evolution behaviors.

  8. Standardized method for reproducing the sequential X-rays flap

    International Nuclear Information System (INIS)

    Brenes, Alejandra; Molina, Katherine; Gudino, Sylvia

    2009-01-01

    A method is validated to estandardize in the taking, developing and analysis of bite-wing radiographs taken in sequential way, in order to compare and evaluate detectable changes in the evolution of the interproximal lesions through time. A radiographic positioner called XCP® is modified by means of a rigid acrylic guide, to achieve proper of the X ray equipment core positioning relative to the XCP® ring and the reorientation during the sequential x-rays process. 16 subjects of 4 to 40 years old are studied for a total number of 32 registries. Two x-rays of the same block of teeth of each subject have been taken in sequential way, with a minimal difference of 30 minutes between each one, before the placement of radiographic attachment. The images have been digitized with a Super Cam® scanner and imported to a software. The measurements in X and Y-axis for both x-rays were performed to proceed to compare. The intraclass correlation index (ICI) has shown that the proposed method is statistically related to measurement (mm) obtained in the X and Y-axis for both sequential series of x-rays (p=0.01). The measures of central tendency and dispersion have shown that the usual occurrence is indifferent between the two measurements (Mode 0.000 and S = 0083 and 0.109) and that the probability of occurrence of different values is lower than expected. (author) [es

  9. Modeling sequential context effects in diagnostic interpretation of screening mammograms.

    Science.gov (United States)

    Alamudun, Folami; Paulus, Paige; Yoon, Hong-Jun; Tourassi, Georgia

    2018-07-01

    Prior research has shown that physicians' medical decisions can be influenced by sequential context, particularly in cases where successive stimuli exhibit similar characteristics when analyzing medical images. This type of systematic error is known to psychophysicists as sequential context effect as it indicates that judgments are influenced by features of and decisions about the preceding case in the sequence of examined cases, rather than being based solely on the peculiarities unique to the present case. We determine if radiologists experience some form of context bias, using screening mammography as the use case. To this end, we explore correlations between previous perceptual behavior and diagnostic decisions and current decisions. We hypothesize that a radiologist's visual search pattern and diagnostic decisions in previous cases are predictive of the radiologist's current diagnostic decisions. To test our hypothesis, we tasked 10 radiologists of varied experience to conduct blind reviews of 100 four-view screening mammograms. Eye-tracking data and diagnostic decisions were collected from each radiologist under conditions mimicking clinical practice. Perceptual behavior was quantified using the fractal dimension of gaze scanpath, which was computed using the Minkowski-Bouligand box-counting method. To test the effect of previous behavior and decisions, we conducted a multifactor fixed-effects ANOVA. Further, to examine the predictive value of previous perceptual behavior and decisions, we trained and evaluated a predictive model for radiologists' current diagnostic decisions. ANOVA tests showed that previous visual behavior, characterized by fractal analysis, previous diagnostic decisions, and image characteristics of previous cases are significant predictors of current diagnostic decisions. Additionally, predictive modeling of diagnostic decisions showed an overall improvement in prediction error when the model is trained on additional information about

  10. Systematic Assessment of the Impact of User Roles on Network Flow Patterns

    Science.gov (United States)

    2017-09-01

    a system at IP address c_IPj can be expressed as D[ui][c_ip j]. Specifying use of a specific protocol ( prk ), server port (spl) and distant end IP...address (e_ipm) can be expressed as D[ui][c_ip j][ prk ][spl][e_ipm]. 3.2 Patterns Within Flow Sets We define patterns within a set of Netflow records as...address, protocol, server port, and endpoint IP address (D[ui][c_ip j][ prk ][spl][e_ipm]) we identified sequential flow pairs, matching each flow with

  11. The composite sequential clustering technique for analysis of multispectral scanner data

    Science.gov (United States)

    Su, M. Y.

    1972-01-01

    The clustering technique consists of two parts: (1) a sequential statistical clustering which is essentially a sequential variance analysis, and (2) a generalized K-means clustering. In this composite clustering technique, the output of (1) is a set of initial clusters which are input to (2) for further improvement by an iterative scheme. This unsupervised composite technique was employed for automatic classification of two sets of remote multispectral earth resource observations. The classification accuracy by the unsupervised technique is found to be comparable to that by traditional supervised maximum likelihood classification techniques. The mathematical algorithms for the composite sequential clustering program and a detailed computer program description with job setup are given.

  12. Alternatives to the sequential lineup: the importance of controlling the pictures.

    Science.gov (United States)

    Lindsay, R C; Bellinger, K

    1999-06-01

    Because sequential lineups reduce false-positive choices, their use has been recommended (R. C. L. Lindsay, 1999; R. C. L. Lindsay & G. L. Wells, 1985). Blind testing is included in the recommended procedures. Police, concerned about blind testing, devised alternative procedures, including self-administered sequential lineups, to reduce use of relative judgments (G. L. Wells, 1984) while permitting the investigating officer to conduct the procedure. Identification data from undergraduates exposed to a staged crime (N = 165) demonstrated that 4 alternative identification procedures tested were less effective than the original sequential lineup. Allowing witnesses to control the photographs resulted in higher rates of false-positive identification. Self-reports of using relative judgments were shown to be postdictive of decision accuracy.

  13. Work–Family Conflict and Mental Health Among Female Employees: A Sequential Mediation Model via Negative Affect and Perceived Stress

    Science.gov (United States)

    Zhou, Shiyi; Da, Shu; Guo, Heng; Zhang, Xichao

    2018-01-01

    After the implementation of the universal two-child policy in 2016, more and more working women have found themselves caught in the dilemma of whether to raise a baby or be promoted, which exacerbates work–family conflicts among Chinese women. Few studies have examined the mediating effect of negative affect. The present study combined the conservation of resources model and affective events theory to examine the sequential mediating effect of negative affect and perceived stress in the relationship between work–family conflict and mental health. A valid sample of 351 full-time Chinese female employees was recruited in this study, and participants voluntarily answered online questionnaires. Pearson correlation analysis, structural equation modeling, and multiple mediation analysis were used to examine the relationships between work–family conflict, negative affect, perceived stress, and mental health in full-time female employees. We found that women’s perceptions of both work-to-family conflict and family-to-work conflict were significant negatively related to mental health. Additionally, the results showed that negative affect and perceived stress were negatively correlated with mental health. The 95% confidence intervals indicated the sequential mediating effect of negative affect and stress in the relationship between work–family conflict and mental health was significant, which supported the hypothesized sequential mediation model. The findings suggest that work–family conflicts affected the level of self-reported mental health, and this relationship functioned through the two sequential mediators of negative affect and perceived stress. PMID:29719522

  14. Work-Family Conflict and Mental Health Among Female Employees: A Sequential Mediation Model via Negative Affect and Perceived Stress.

    Science.gov (United States)

    Zhou, Shiyi; Da, Shu; Guo, Heng; Zhang, Xichao

    2018-01-01

    After the implementation of the universal two-child policy in 2016, more and more working women have found themselves caught in the dilemma of whether to raise a baby or be promoted, which exacerbates work-family conflicts among Chinese women. Few studies have examined the mediating effect of negative affect. The present study combined the conservation of resources model and affective events theory to examine the sequential mediating effect of negative affect and perceived stress in the relationship between work-family conflict and mental health. A valid sample of 351 full-time Chinese female employees was recruited in this study, and participants voluntarily answered online questionnaires. Pearson correlation analysis, structural equation modeling, and multiple mediation analysis were used to examine the relationships between work-family conflict, negative affect, perceived stress, and mental health in full-time female employees. We found that women's perceptions of both work-to-family conflict and family-to-work conflict were significant negatively related to mental health. Additionally, the results showed that negative affect and perceived stress were negatively correlated with mental health. The 95% confidence intervals indicated the sequential mediating effect of negative affect and stress in the relationship between work-family conflict and mental health was significant, which supported the hypothesized sequential mediation model. The findings suggest that work-family conflicts affected the level of self-reported mental health, and this relationship functioned through the two sequential mediators of negative affect and perceived stress.

  15. Work–Family Conflict and Mental Health Among Female Employees: A Sequential Mediation Model via Negative Affect and Perceived Stress

    Directory of Open Access Journals (Sweden)

    Shiyi Zhou

    2018-04-01

    Full Text Available After the implementation of the universal two-child policy in 2016, more and more working women have found themselves caught in the dilemma of whether to raise a baby or be promoted, which exacerbates work–family conflicts among Chinese women. Few studies have examined the mediating effect of negative affect. The present study combined the conservation of resources model and affective events theory to examine the sequential mediating effect of negative affect and perceived stress in the relationship between work–family conflict and mental health. A valid sample of 351 full-time Chinese female employees was recruited in this study, and participants voluntarily answered online questionnaires. Pearson correlation analysis, structural equation modeling, and multiple mediation analysis were used to examine the relationships between work–family conflict, negative affect, perceived stress, and mental health in full-time female employees. We found that women’s perceptions of both work-to-family conflict and family-to-work conflict were significant negatively related to mental health. Additionally, the results showed that negative affect and perceived stress were negatively correlated with mental health. The 95% confidence intervals indicated the sequential mediating effect of negative affect and stress in the relationship between work–family conflict and mental health was significant, which supported the hypothesized sequential mediation model. The findings suggest that work–family conflicts affected the level of self-reported mental health, and this relationship functioned through the two sequential mediators of negative affect and perceived stress.

  16. Sequential Apparent Diffusion Coefficient for Assessment of Tumor Progression in Patients with Low-Grade Glioma.

    Science.gov (United States)

    Chen, I E; Swinburne, N; Tsankova, N M; Hefti, M M; Aggarwal, A; Doshi, A H; Hormigo, A; Delman, B N; Nael, K

    2018-04-19

    Early and accurate identification of tumor progression in patients with low-grade gliomas is challenging. We aimed to assess the role of quantitative ADC analysis in the sequential follow-up of patients with low-grade gliomas as a potential imaging marker of tumor stability or progression. In this retrospective study, patients with a diagnosis of low-grade glioma with at least 12 months of imaging follow-up were retrospectively reviewed. Two neuroradiologists independently reviewed sequential MR imaging in each patient to determine tumor progression using the Response Assessment in Neuro-Oncology criteria. Normalized mean ADC (ADC mean ) and 10th percentile ADC (ADC 10 ) values from FLAIR hyperintense tumor volume were calculated for each MR image and compared between patients with stable disease versus tumor progression using univariate analysis. The interval change of ADC values between sequential scans was used to differentiate stable disease from progression using the Fisher exact test. Twenty-eight of 69 patients who were evaluated met our inclusion criteria. Fifteen patients were classified as stable versus 13 patients as having progression based on consensus reads of MRIs and the Response Assessment in Neuro-Oncology criteria. The interval change of ADC values showed greater concordance with ultimate lesion disposition than quantitative ADC values at a single time point. The interval change in ADC 10 matched the expected pattern in 12/13 patients with tumor progression (overall diagnostic accuracy of 86%, P average, the ADC 10 interval change predicted progression 8 months before conventional MR imaging. The interval change of ADC 10 values can be used to identify progression versus stability of low-grade gliomas with a diagnostic accuracy of 86% and before apparent radiologic progression on conventional MR imaging. © 2018 by American Journal of Neuroradiology.

  17. Gambler's fallacy, hot hand belief, and the time of patterns

    Directory of Open Access Journals (Sweden)

    Hongbin Wang

    2010-04-01

    Full Text Available The gambler's fallacy and the hot hand belief have been classified as two exemplars of human misperceptions of random sequential events. This article examines the times of pattern occurrences where a fair or biased coin is tossed repeatedly. We demonstrate that, due to different pattern composition, two different statistics (mean time and waiting time can arise from the same independent Bernoulli trials. When the coin is fair, the mean time is equal for all patterns of the same length but the waiting time is the longest for streak patterns. When the coin is biased, both mean time and waiting time change more rapidly with the probability of heads for a streak pattern than for a non-streak pattern. These facts might provide a new insight for understanding why people view streak patterns as rare and remarkable. The statistics of waiting time may not justify the prediction by the gambler's fallacy, but paying attention to streaks in the hot hand belief appears to be meaningful in detecting the changes in the underlying process.

  18. A Bayesian sequential processor approach to spectroscopic portal system decisions

    Energy Technology Data Exchange (ETDEWEB)

    Sale, K; Candy, J; Breitfeller, E; Guidry, B; Manatt, D; Gosnell, T; Chambers, D

    2007-07-31

    The development of faster more reliable techniques to detect radioactive contraband in a portal type scenario is an extremely important problem especially in this era of constant terrorist threats. Towards this goal the development of a model-based, Bayesian sequential data processor for the detection problem is discussed. In the sequential processor each datum (detector energy deposit and pulse arrival time) is used to update the posterior probability distribution over the space of model parameters. The nature of the sequential processor approach is that a detection is produced as soon as it is statistically justified by the data rather than waiting for a fixed counting interval before any analysis is performed. In this paper the Bayesian model-based approach, physics and signal processing models and decision functions are discussed along with the first results of our research.

  19. Sequential lineup presentation promotes less-biased criterion setting but does not improve discriminability.

    Science.gov (United States)

    Palmer, Matthew A; Brewer, Neil

    2012-06-01

    When compared with simultaneous lineup presentation, sequential presentation has been shown to reduce false identifications to a greater extent than it reduces correct identifications. However, there has been much debate about whether this difference in identification performance represents improved discriminability or more conservative responding. In this research, data from 22 experiments that compared sequential and simultaneous lineups were analyzed using a compound signal-detection model, which is specifically designed to describe decision-making performance on tasks such as eyewitness identification tests. Sequential (cf. simultaneous) presentation did not influence discriminability, but produced a conservative shift in response bias that resulted in less-biased choosing for sequential than simultaneous lineups. These results inform understanding of the effects of lineup presentation mode on eyewitness identification decisions.

  20. Linking gene regulation to cell behaviors in the posterior growth zone of sequentially segmenting arthropods.

    Science.gov (United States)

    Williams, Terri A; Nagy, Lisa M

    2017-05-01

    Virtually all arthropods all arthropods add their body segments sequentially, one by one in an anterior to posterior progression. That process requires not only segment specification but typically growth and elongation. Here we review the functions of some of the key genes that regulate segmentation: Wnt, caudal, Notch pathway, and pair-rule genes, and discuss what can be inferred about their evolution. We focus on how these regulatory factors are integrated with growth and elongation and discuss the importance and challenges of baseline measures of growth and elongation. We emphasize a perspective that integrates the genetic regulation of segment patterning with the cellular mechanisms of growth and elongation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Estimation After a Group Sequential Trial.

    Science.gov (United States)

    Milanzi, Elasma; Molenberghs, Geert; Alonso, Ariel; Kenward, Michael G; Tsiatis, Anastasios A; Davidian, Marie; Verbeke, Geert

    2015-10-01

    Group sequential trials are one important instance of studies for which the sample size is not fixed a priori but rather takes one of a finite set of pre-specified values, dependent on the observed data. Much work has been devoted to the inferential consequences of this design feature. Molenberghs et al (2012) and Milanzi et al (2012) reviewed and extended the existing literature, focusing on a collection of seemingly disparate, but related, settings, namely completely random sample sizes, group sequential studies with deterministic and random stopping rules, incomplete data, and random cluster sizes. They showed that the ordinary sample average is a viable option for estimation following a group sequential trial, for a wide class of stopping rules and for random outcomes with a distribution in the exponential family. Their results are somewhat surprising in the sense that the sample average is not optimal, and further, there does not exist an optimal, or even, unbiased linear estimator. However, the sample average is asymptotically unbiased, both conditionally upon the observed sample size as well as marginalized over it. By exploiting ignorability they showed that the sample average is the conventional maximum likelihood estimator. They also showed that a conditional maximum likelihood estimator is finite sample unbiased, but is less efficient than the sample average and has the larger mean squared error. Asymptotically, the sample average and the conditional maximum likelihood estimator are equivalent. This previous work is restricted, however, to the situation in which the the random sample size can take only two values, N = n or N = 2 n . In this paper, we consider the more practically useful setting of sample sizes in a the finite set { n 1 , n 2 , …, n L }. It is shown that the sample average is then a justifiable estimator , in the sense that it follows from joint likelihood estimation, and it is consistent and asymptotically unbiased. We also show why

  2. Simultaneous optimization of sequential IMRT plans

    International Nuclear Information System (INIS)

    Popple, Richard A.; Prellop, Perri B.; Spencer, Sharon A.; Santos, Jennifer F. de los; Duan, Jun; Fiveash, John B.; Brezovich, Ivan A.

    2005-01-01

    Radiotherapy often comprises two phases, in which irradiation of a volume at risk for microscopic disease is followed by a sequential dose escalation to a smaller volume either at a higher risk for microscopic disease or containing only gross disease. This technique is difficult to implement with intensity modulated radiotherapy, as the tolerance doses of critical structures must be respected over the sum of the two plans. Techniques that include an integrated boost have been proposed to address this problem. However, clinical experience with such techniques is limited, and many clinicians are uncomfortable prescribing nonconventional fractionation schemes. To solve this problem, we developed an optimization technique that simultaneously generates sequential initial and boost IMRT plans. We have developed an optimization tool that uses a commercial treatment planning system (TPS) and a high level programming language for technical computing. The tool uses the TPS to calculate the dose deposition coefficients (DDCs) for optimization. The DDCs were imported into external software and the treatment ports duplicated to create the boost plan. The initial, boost, and tolerance doses were specified and used to construct cost functions. The initial and boost plans were optimized simultaneously using a gradient search technique. Following optimization, the fluence maps were exported to the TPS for dose calculation. Seven patients treated using sequential techniques were selected from our clinical database. The initial and boost plans used to treat these patients were developed independently of each other by dividing the tolerance doses proportionally between the initial and boost plans and then iteratively optimizing the plans until a summation that met the treatment goals was obtained. We used the simultaneous optimization technique to generate plans that met the original planning goals. The coverage of the initial and boost target volumes in the simultaneously optimized

  3. Optimal Sequential Resource Sharing and Exchange in Multi-Agent Systems

    OpenAIRE

    Xiao, Yuanzhang

    2014-01-01

    Central to the design of many engineering systems and social networks is to solve the underlying resource sharing and exchange problems, in which multiple decentralized agents make sequential decisions over time to optimize some long-term performance metrics. It is challenging for the decentralized agents to make optimal sequential decisions because of the complicated coupling among the agents and across time. In this dissertation, we mainly focus on three important classes of multi-agent seq...

  4. Subclinical interstitial lung involvement in rheumatic diseases. Correlations of high-resolution Computed Tomography patterns with functional and cytologic findings

    International Nuclear Information System (INIS)

    Salaffi, F.; Baldelli, S.

    1999-01-01

    The aims of this study were to quantify the severity and extent of subclinical interstitial lung disease as depicted on HRCT and to study the relationship between the patterns of lung disease quantified by HRCT and the functional parameters and bronchoalveolar lavage findings in patients with rheumatic diseases. The results confirm that HRCT is a sensitive tool in detecting interstitial lung disease in patients with rheumatic diseases with no signs and symptoms of pulmonary involvement. The relationship between the different HRCT patterns and bronchoalveolar lavage cell profiles can identify patients at higher risk of developing irreversible lung fibrosis. A long-term, prospective follow-up study is needed to determine whether these patients will develop over pulmonary disease [it

  5. S.M.P. SEQUENTIAL MATHEMATICS PROGRAM.

    Science.gov (United States)

    CICIARELLI, V; LEONARD, JOSEPH

    A SEQUENTIAL MATHEMATICS PROGRAM BEGINNING WITH THE BASIC FUNDAMENTALS ON THE FOURTH GRADE LEVEL IS PRESENTED. INCLUDED ARE AN UNDERSTANDING OF OUR NUMBER SYSTEM, AND THE BASIC OPERATIONS OF WORKING WITH WHOLE NUMBERS--ADDITION, SUBTRACTION, MULTIPLICATION, AND DIVISION. COMMON FRACTIONS ARE TAUGHT IN THE FIFTH, SIXTH, AND SEVENTH GRADES. A…

  6. Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm.

    Science.gov (United States)

    Arber, Madeleine M; Ireland, Michael J; Feger, Roy; Marrington, Jessica; Tehan, Joshua; Tehan, Gerald

    2017-01-01

    Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource) models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration). Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors) as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research.

  7. Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm

    Directory of Open Access Journals (Sweden)

    Madeleine M. Arber

    2017-09-01

    Full Text Available Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration. Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research.

  8. How Do Children Deal With Conflict? A Developmental Study of Sequential Conflict Modulation

    Science.gov (United States)

    Smulders, Silvan F. A.; Soetens, Eric L. L.; van der Molen, Maurits W.

    2018-01-01

    This study examined age-related differences in sequential conflict modulation (SCM), elicited in three tasks requiring the inhibition of pre-potent responses; a Simon task, an S-R compatibility (SRC) task and a hybrid Choice-reaction/NoGo task. The primary focus was on age-related changes in performance changes following a conflict trial. A secondary aim was to assess whether SCM follows different developmental trajectories depending on the type of conflict elicited by the tasks. The tasks were presented to three different groups of participants with an age range between 7- to 25-years—one group of participants for each task. For each task, the response-to-stimulus interval (RSI) was manipulated (50 vs. 500 ms) across trial blocks to assess time-dependent changes in conflict modulation. The results showed SCM for all three tasks, although the specific patterns differed between tasks and RSIs. Importantly, the magnitude of SCM decreased with advancing age, but this developmental trend did not survive when considering age-group differences in basic response speed. The current results contribute to the emerging evidence suggesting that patterns of SCM are task specific and were interpreted in terms of multiple bottom-up control mechanisms. PMID:29875718

  9. Sequential Logic Model Deciphers Dynamic Transcriptional Control of Gene Expressions

    Science.gov (United States)

    Yeo, Zhen Xuan; Wong, Sum Thai; Arjunan, Satya Nanda Vel; Piras, Vincent; Tomita, Masaru; Selvarajoo, Kumar; Giuliani, Alessandro; Tsuchiya, Masa

    2007-01-01

    Background Cellular signaling involves a sequence of events from ligand binding to membrane receptors through transcription factors activation and the induction of mRNA expression. The transcriptional-regulatory system plays a pivotal role in the control of gene expression. A novel computational approach to the study of gene regulation circuits is presented here. Methodology Based on the concept of finite state machine, which provides a discrete view of gene regulation, a novel sequential logic model (SLM) is developed to decipher control mechanisms of dynamic transcriptional regulation of gene expressions. The SLM technique is also used to systematically analyze the dynamic function of transcriptional inputs, the dependency and cooperativity, such as synergy effect, among the binding sites with respect to when, how much and how fast the gene of interest is expressed. Principal Findings SLM is verified by a set of well studied expression data on endo16 of Strongylocentrotus purpuratus (sea urchin) during the embryonic midgut development. A dynamic regulatory mechanism for endo16 expression controlled by three binding sites, UI, R and Otx is identified and demonstrated to be consistent with experimental findings. Furthermore, we show that during transition from specification to differentiation in wild type endo16 expression profile, SLM reveals three binary activities are not sufficient to explain the transcriptional regulation of endo16 expression and additional activities of binding sites are required. Further analyses suggest detailed mechanism of R switch activity where indirect dependency occurs in between UI activity and R switch during specification to differentiation stage. Conclusions/Significance The sequential logic formalism allows for a simplification of regulation network dynamics going from a continuous to a discrete representation of gene activation in time. In effect our SLM is non-parametric and model-independent, yet providing rich biological

  10. Sequential logic model deciphers dynamic transcriptional control of gene expressions.

    Directory of Open Access Journals (Sweden)

    Zhen Xuan Yeo

    Full Text Available BACKGROUND: Cellular signaling involves a sequence of events from ligand binding to membrane receptors through transcription factors activation and the induction of mRNA expression. The transcriptional-regulatory system plays a pivotal role in the control of gene expression. A novel computational approach to the study of gene regulation circuits is presented here. METHODOLOGY: Based on the concept of finite state machine, which provides a discrete view of gene regulation, a novel sequential logic model (SLM is developed to decipher control mechanisms of dynamic transcriptional regulation of gene expressions. The SLM technique is also used to systematically analyze the dynamic function of transcriptional inputs, the dependency and cooperativity, such as synergy effect, among the binding sites with respect to when, how much and how fast the gene of interest is expressed. PRINCIPAL FINDINGS: SLM is verified by a set of well studied expression data on endo16 of Strongylocentrotus purpuratus (sea urchin during the embryonic midgut development. A dynamic regulatory mechanism for endo16 expression controlled by three binding sites, UI, R and Otx is identified and demonstrated to be consistent with experimental findings. Furthermore, we show that during transition from specification to differentiation in wild type endo16 expression profile, SLM reveals three binary activities are not sufficient to explain the transcriptional regulation of endo16 expression and additional activities of binding sites are required. Further analyses suggest detailed mechanism of R switch activity where indirect dependency occurs in between UI activity and R switch during specification to differentiation stage. CONCLUSIONS/SIGNIFICANCE: The sequential logic formalism allows for a simplification of regulation network dynamics going from a continuous to a discrete representation of gene activation in time. In effect our SLM is non-parametric and model-independent, yet

  11. [Interactive patterns detection in family communication with adolescents].

    Science.gov (United States)

    Gimeno Collado, Adelina; Anguera Argilaga, M Teresa; Berzosa Sanz, Amparo; Ramírez Ramírez, Luis

    2006-11-01

    Interactive patterns detection in family communication with adolescents. Nondistant communication is a relevant indicator for family functionality valuation. The goal of this study is to analyze this communication in order to identify specific kinds of leadership, interaction patterns and the relation between verbal and nonverbal elements in communication. The observational design exposed is an idiographic one, punctual and multidimensional, which uses field format as observation instrument. Participants were seven standardized families made up of both ancestors and an adolescent son or daughter. According to the family models analyzed, results show a predominantly democratic communication style in adults with recurrent support expressions. The sequential analysis incorporates only categories from the emitter point of view, and detects relevant sequences which show symmetric interaction between all three family members. Verbal and nonverbal channels provide complementary information. Depending on adolescents' gender different patterns in behaviour can be identified as well.

  12. Sequential sputtered Co-HfO{sub 2} granular films

    Energy Technology Data Exchange (ETDEWEB)

    Chadha, M.; Ng, V.

    2017-03-15

    A systematic study of magnetic, magneto-transport and micro-structural properties of Co-HfO{sub 2} granular films fabricated by sequential sputtering is presented. We demonstrate reduction in ferromagnetic-oxide formation by using HfO{sub 2} as the insulting matrix. Microstructure evaluation of the films showed that the film structure consisted of discrete hcp-Co grains embedded in HfO{sub 2} matrix. Films with varying compositions were prepared and their macroscopic properties were studied. We correlate the variation in these properties to the variation in film microstructure. Our study shows that Co-HfO{sub 2} films with reduced cobalt oxide and varying properties can be prepared using sequential sputtering technique. - Highlights: • Co-HfO{sub 2} granular films were prepared using sequential sputtering. • A reduction in ferromagnetic-oxide formation is observed. • Co-HfO{sub 2} films display superparamagnetism and tunnelling magneto-resistance. • Varying macroscopic properties were achieved by changing film composition. • Applications can be found in moderate MR sensors and high –frequency RF devices.

  13. Cortical responses following simultaneous and sequential retinal neurostimulation with different return configurations.

    Science.gov (United States)

    Barriga-Rivera, Alejandro; Morley, John W; Lovell, Nigel H; Suaning, Gregg J

    2016-08-01

    Researchers continue to develop visual prostheses towards safer and more efficacious systems. However limitations still exist in the number of stimulating channels that can be integrated. Therefore there is a need for spatial and time multiplexing techniques to provide improved performance of the current technology. In particular, bright and high-contrast visual scenes may require simultaneous activation of several electrodes. In this research, a 24-electrode array was suprachoroidally implanted in three normally-sighted cats. Multi-unit activity was recorded from the primary visual cortex. Four stimulation strategies were contrasted to provide activation of seven electrodes arranged hexagonally: simultaneous monopolar, sequential monopolar, sequential bipolar and hexapolar. Both monopolar configurations showed similar cortical activation maps. Hexapolar and sequential bipolar configurations activated a lower number of cortical channels. Overall, the return configuration played a more relevant role in cortical activation than time multiplexing and thus, rapid sequential stimulation may assist in reducing the number of channels required to activate large retinal areas.

  14. Sequential Versus Simultaneous Market Delineation: The Relevant Antitrust Market for Salmon

    DEFF Research Database (Denmark)

    Haldrup, Niels; Peter, Møllgaard

    Delineation of the relevant market forms a pivotal part of most antitrust cases. The standard approach is sequential. First the product market is delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographical dimension will no...... and geographical markets. Using a unique data set for prices of Norwegian and Scottish salmon, we propose a methodology for simultaneous market delineation and we demonstrate that compared to a sequential approach conclusions will be reversed.......Delineation of the relevant market forms a pivotal part of most antitrust cases. The standard approach is sequential. First the product market is delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographical dimension...

  15. Baselining PMU Data to Find Patterns and Anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G.; Follum, James D.; Freeman, Kimberly A.; Dagle, Jeffery E.

    2016-10-25

    This paper looks at the application of situational awareness methodologies with respect to power grid data. These methodologies establish baselines that look for typical patterns and atypical behavior in the data. The objectives of the baselining analyses are to provide: real-time analytics, the capability to look at historical trends and events, and reliable predictions of the near future state of the grid. Multivariate algorithms were created to establish normal baseline behavior and then score each moment in time according to its variance from the baseline. Detailed multivariate analytical techniques are described in this paper that produced ways to identify typical patterns and atypical behavior. In this case, atypical behavior is behavior that is unenvisioned. Visualizations were also produced to help explain the behavior that was identified mathematically. Examples are shown to help describe how to read and interpret the analyses and visualizations. Preliminary work has been performed on PMU data sets from BPA (Bonneville Power Administration) and EI (Eastern Interconnect). Actual results are not fully shown here because of confidentiality issues. Comparisons between atypical events found mathematically and actual events showed that many of the actual events are also atypical events; however there are many atypical events that do not correlate to any actual events. Additional work needs to be done to help classify the atypical events into actual events, so that the importance of the events can be better understood.

  16. Efficacy of premixed versus sequential administration of ...

    African Journals Online (AJOL)

    sequential administration in separate syringes on block characteristics, haemodynamic parameters, side effect profile and postoperative analgesic requirement. Trial design: This was a prospective, randomised clinical study. Method: Sixty orthopaedic patients scheduled for elective lower limb surgery under spinal ...

  17. [Sequential degradation of p-cresol by photochemical and biological methods].

    Science.gov (United States)

    Karetnikova, E A; Chaĭkovskaia, O N; Sokolova, I V; Nikitina, L I

    2008-01-01

    Sequential photo- and biodegradation of p-cresol was studied using a mercury lamp, as well as KrCl and XeCl excilamps. Preirradiation of p-cresol at a concentration of 10(-4) M did not affect the rate of its subsequent biodegradation. An increase in the concentration of p-cresol to 10(-3) M and in the duration preliminary UV irradiation inhibited subsequent biodegradation. Biodegradation of p-cresol was accompanied by the formation of a product with a fluorescence maximum at 365 nm (lambdaex 280 nm), and photodegradation yielded a compound fluorescing at 400 nm (lambdaex 330 nm). Sequential UV and biodegradation led to the appearance of bands in the fluorescence spectra that were ascribed to p-cresol and its photolysis products. It was shown that sequential use of biological and photochemical degradation results in degradation of not only the initial toxicant but also the metabolites formed during its biodegradation.

  18. Comparison of Capsule Endoscopy Findings to Subsequent Double Balloon Enteroscopy: A Dual Center Experience

    Directory of Open Access Journals (Sweden)

    Amandeep S. Kalra

    2015-01-01

    Full Text Available Background. There has been a growing use of both capsule endoscopy (CE and double balloon enteroscopy (DBE to diagnose and treat patients with obscure gastrointestinal blood loss and suspected small bowel pathology. Aim. To compare and correlate sequential CE and DBE findings in a large series of patients at two tertiary level hospitals in Wisconsin. Methods. An IRB approved retrospective study of patients who underwent sequential CE and DBE, at two separate tertiary care academic centers from May 2007 to December 2011, was performed. Results. 116 patients were included in the study. The mean age ± SD was 66.6 ± 13.2 years. There were 56% males and 43.9% females. Measure of agreement between prior capsule and DBE findings was performed using kappa statistics, which gave kappa value of 0.396 with P<0.001. Also contingency coefficient was calculated and was found to be 0.732 (P<0.001. Conclusions. Our study showed good overall agreement between DBE and CE. Findings of angioectasia had maximum agreement of 69%.

  19. Sequential-Simultaneous Analysis of Japanese Children's Performance on the Japanese McCarthy.

    Science.gov (United States)

    Ishikuma, Toshinori; And Others

    This study explored the hypothesis that Japanese children perform significantly better on simultaneous processing than on sequential processing. The Kaufman Assessment Battery for Children (K-ABC) served as the criterion of the two types of mental processing. Regression equations to predict Sequential and Simultaneous processing from McCarthy…

  20. Acquisition of Inductive Biconditional Reasoning Skills: Training of Simultaneous and Sequential Processing.

    Science.gov (United States)

    Lee, Seong-Soo

    1982-01-01

    Tenth-grade students (n=144) received training on one of three processing methods: coding-mapping (simultaneous), coding only, or decision tree (sequential). The induced simultaneous processing strategy worked optimally under rule learning, while the sequential strategy was difficult to induce and/or not optimal for rule-learning operations.…

  1. The reproducibility and variability of sequential left ventricular ejection fraction measurements by the nuclear stethoscope

    International Nuclear Information System (INIS)

    Kurata, Chinori; Hayashi, Hideharu; Kobayashi, Akira; Yamazaki, Noboru

    1986-01-01

    We evaluated the reproducibility and variability of sequential left ventricular ejection fraction (LVEF) measurements by the nuclear stethoscope in 72 patients. The group as a whole demonstrated excellent reproducibility (r = 0.96). However, repeat LVEF measurements by the nuclear stethoscope at 5-minute interval showed around 9 % absolute difference, at 95 % confidence levels, from one measurement to the next. The finding indicates that a change in LVEF greater than 9 % is necessary for determining an acute effect of an intervention in individual cases. (author)

  2. Use of the K-ABC with Children in Zaire, Africa: An Evaluation of the Sequential-Simultaneous Processing Distinction within an Intercultural Context.

    Science.gov (United States)

    Giordani, Bruno; And Others

    1996-01-01

    Evaluation of the Kaufman Assessment Battery for Children (K-ABC) with 130 primary school children in Zaire revealed three findings: (1) the distinction between sequential processing and simultaneous processing was valid; (2) the K-ABC discriminated effectively among grade levels, health and family environment variables, and tribal membership; and…

  3. Time scale of random sequential adsorption.

    Science.gov (United States)

    Erban, Radek; Chapman, S Jonathan

    2007-04-01

    A simple multiscale approach to the diffusion-driven adsorption from a solution to a solid surface is presented. The model combines two important features of the adsorption process: (i) The kinetics of the chemical reaction between adsorbing molecules and the surface and (ii) geometrical constraints on the surface made by molecules which are already adsorbed. The process (i) is modeled in a diffusion-driven context, i.e., the conditional probability of adsorbing a molecule provided that the molecule hits the surface is related to the macroscopic surface reaction rate. The geometrical constraint (ii) is modeled using random sequential adsorption (RSA), which is the sequential addition of molecules at random positions on a surface; one attempt to attach a molecule is made per one RSA simulation time step. By coupling RSA with the diffusion of molecules in the solution above the surface the RSA simulation time step is related to the real physical time. The method is illustrated on a model of chemisorption of reactive polymers to a virus surface.

  4. Sequential voluntary cough and aspiration or aspiration risk in Parkinson's disease.

    Science.gov (United States)

    Hegland, Karen Wheeler; Okun, Michael S; Troche, Michelle S

    2014-08-01

    Disordered swallowing, or dysphagia, is almost always present to some degree in people with Parkinson's disease (PD), either causing aspiration or greatly increasing the risk for aspiration during swallowing. This likely contributes to aspiration pneumonia, a leading cause of death in this patient population. Effective airway protection is dependent upon multiple behaviors, including cough and swallowing. Single voluntary cough function is disordered in people with PD and dysphagia. However, the appropriate response to aspirate material is more than one cough, or sequential cough. The goal of this study was to examine voluntary sequential coughing in people with PD, with and without dysphagia. Forty adults diagnosed with idiopathic PD produced two trials of sequential voluntary cough. The cough airflows were obtained using pneumotachograph and facemask and subsequently digitized and recorded. All participants received a modified barium swallow study as part of their clinical care, and the worst penetration-aspiration score observed was used to determine whether the patient had dysphagia. There were significant differences in the compression phase duration, peak expiratory flow rates, and amount of air expired of the sequential cough produced by participants with and without dysphagia. The presence of dysphagia in people with PD is associated with disordered cough function. Sequential cough, which is important in removing aspirate material from large- and smaller-diameter airways, is also impaired in people with PD and dysphagia compared with those without dysphagia. There may be common neuroanatomical substrates for cough and swallowing impairment in PD leading to the co-occurrence of these dysfunctions.

  5. Sequential effects in judgements of attractiveness: the influences of face race and sex.

    Directory of Open Access Journals (Sweden)

    Robin S S Kramer

    Full Text Available In perceptual decision-making, a person's response on a given trial is influenced by their response on the immediately preceding trial. This sequential effect was initially demonstrated in psychophysical tasks, but has now been found in more complex, real-world judgements. The similarity of the current and previous stimuli determines the nature of the effect, with more similar items producing assimilation in judgements, while less similarity can cause a contrast effect. Previous research found assimilation in ratings of facial attractiveness, and here, we investigated whether this effect is influenced by the social categories of the faces presented. Over three experiments, participants rated the attractiveness of own- (White and other-race (Chinese faces of both sexes that appeared successively. Through blocking trials by race (Experiment 1, sex (Experiment 2, or both dimensions (Experiment 3, we could examine how sequential judgements were altered by the salience of different social categories in face sequences. For sequences that varied in sex alone, own-race faces showed significantly less opposite-sex assimilation (male and female faces perceived as dissimilar, while other-race faces showed equal assimilation for opposite- and same-sex sequences (male and female faces were not differentiated. For sequences that varied in race alone, categorisation by race resulted in no opposite-race assimilation for either sex of face (White and Chinese faces perceived as dissimilar. For sequences that varied in both race and sex, same-category assimilation was significantly greater than opposite-category. Our results suggest that the race of a face represents a superordinate category relative to sex. These findings demonstrate the importance of social categories when considering sequential judgements of faces, and also highlight a novel approach for investigating how multiple social dimensions interact during decision-making.

  6. Behaviour of venous flow rates in intermittent sequential pneumatic compression of the legs using different compression strengths

    International Nuclear Information System (INIS)

    Fassmann-Glaser, I.

    1984-01-01

    A study with 25 patients was performed in order to find out whether intermittent, sequential, pneumatic leg compression is of value in the preventive management of thrombosis due to its effect on the venous flow rates. For this purpose, xenon 133 was injected into one of the foot veins and the flow rate in each case determined for the distance between instep and inguen using different compression strengths, with pressure being exerted on the ankle, calf and thigh. Increased flow rates were already measured at an average pressure value of 34.5 mmHg, while the maximum effect was achieved by exerting a pressure of 92.5 mmHg, which increased the flow rate by 366% as compared to the baseline value. The results point to a significant improvement of the venous flow rates due to intermittent, sequential, pneumatic leg compression and thus provide evidence to prove the value of this method in the prevention of hemostasis and thrombosis. (TRV) [de

  7. Effects of sequential and discrete rapid naming on reading in Japanese children with reading difficulty.

    Science.gov (United States)

    Wakamiya, Eiji; Okumura, Tomohito; Nakanishi, Makoto; Takeshita, Takashi; Mizuta, Mekumi; Kurimoto, Naoko; Tamai, Hiroshi

    2011-06-01

    To clarify whether rapid naming ability itself is a main underpinning factor of rapid automatized naming tests (RAN) and how deep an influence the discrete decoding process has on reading, we performed discrete naming tasks and discrete hiragana reading tasks as well as sequential naming tasks and sequential hiragana reading tasks with 38 Japanese schoolchildren with reading difficulty. There were high correlations between both discrete and sequential hiragana reading and sentence reading, suggesting that some mechanism which automatizes hiragana reading makes sentence reading fluent. In object and color tasks, there were moderate correlations between sentence reading and sequential naming, and between sequential naming and discrete naming. But no correlation was found between reading tasks and discrete naming tasks. The influence of rapid naming ability of objects and colors upon reading seemed relatively small, and multi-item processing may work in relation to these. In contrast, in the digit naming task there was moderate correlation between sentence reading and discrete naming, while no correlation was seen between sequential naming and discrete naming. There was moderate correlation between reading tasks and sequential digit naming tasks. Digit rapid naming ability has more direct effect on reading while its effect on RAN is relatively limited. The ratio of how rapid naming ability influences RAN and reading seems to vary according to kind of the stimuli used. An assumption about components in RAN which influence reading is discussed in the context of both sequential processing and discrete naming speed. Copyright © 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  8. STABILIZED SEQUENTIAL QUADRATIC PROGRAMMING: A SURVEY

    Directory of Open Access Journals (Sweden)

    Damián Fernández

    2014-12-01

    Full Text Available We review the motivation for, the current state-of-the-art in convergence results, and some open questions concerning the stabilized version of the sequential quadratic programming algorithm for constrained optimization. We also discuss the tools required for its local convergence analysis, globalization challenges, and extentions of the method to the more general variational problems.

  9. Terminating Sequential Delphi Survey Data Collection

    Science.gov (United States)

    Kalaian, Sema A.; Kasim, Rafa M.

    2012-01-01

    The Delphi survey technique is an iterative mail or electronic (e-mail or web-based) survey method used to obtain agreement or consensus among a group of experts in a specific field on a particular issue through a well-designed and systematic multiple sequential rounds of survey administrations. Each of the multiple rounds of the Delphi survey…

  10. Sequential function approximation on arbitrarily distributed point sets

    Science.gov (United States)

    Wu, Kailiang; Xiu, Dongbin

    2018-02-01

    We present a randomized iterative method for approximating unknown function sequentially on arbitrary point set. The method is based on a recently developed sequential approximation (SA) method, which approximates a target function using one data point at each step and avoids matrix operations. The focus of this paper is on data sets with highly irregular distribution of the points. We present a nearest neighbor replacement (NNR) algorithm, which allows one to sample the irregular data sets in a near optimal manner. We provide mathematical justification and error estimates for the NNR algorithm. Extensive numerical examples are also presented to demonstrate that the NNR algorithm can deliver satisfactory convergence for the SA method on data sets with high irregularity in their point distributions.

  11. Configural and component processing in simultaneous and sequential lineup procedures.

    Science.gov (United States)

    Flowe, Heather D; Smith, Harriet M J; Karoğlu, Nilda; Onwuegbusi, Tochukwu O; Rai, Lovedeep

    2016-01-01

    Configural processing supports accurate face recognition, yet it has never been examined within the context of criminal identification lineups. We tested, using the inversion paradigm, the role of configural processing in lineups. Recent research has found that face discrimination accuracy in lineups is better in a simultaneous compared to a sequential lineup procedure. Therefore, we compared configural processing in simultaneous and sequential lineups to examine whether there are differences. We had participants view a crime video, and then they attempted to identify the perpetrator from a simultaneous or sequential lineup. The test faces were presented either upright or inverted, as previous research has shown that inverting test faces disrupts configural processing. The size of the inversion effect for faces was the same across lineup procedures, indicating that configural processing underlies face recognition in both procedures. Discrimination accuracy was comparable across lineup procedures in both the upright and inversion condition. Theoretical implications of the results are discussed.

  12. Right anterior cerebellum BOLD responses reflect age related changes in Simon task sequential effects.

    Science.gov (United States)

    Aisenberg, D; Sapir, A; Close, A; Henik, A; d'Avossa, G

    2018-01-31

    Participants are slower to report a feature, such as color, when the target appears on the side opposite the instructed response, than when the target appears on the same side. This finding suggests that target location, even when task-irrelevant, interferes with response selection. This effect is magnified in older adults. Lengthening the inter-trial interval, however, suffices to normalize the congruency effect in older adults, by re-establishing young-like sequential effects (Aisenberg et al., 2014). We examined the neurological correlates of age related changes by comparing BOLD signals in young and old participants performing a visual version of the Simon task. Participants reported the color of a peripheral target, by a left or right-hand keypress. Generally, BOLD responses were greater following incongruent than congruent targets. Also, they were delayed and of smaller amplitude in old than young participants. BOLD responses in visual and motor regions were also affected by the congruency of the previous target, suggesting that sequential effects may reflect remapping of stimulus location onto the hand used to make a response. Crucially, young participants showed larger BOLD responses in right anterior cerebellum to incongruent targets, when the previous target was congruent, but smaller BOLD responses to incongruent targets when the previous target was incongruent. Old participants, however, showed larger BOLD responses to congruent than incongruent targets, irrespective of the previous target congruency. We conclude that aging may interfere with the trial by trial updating of the mapping between the task-irrelevant target location and response, which takes place during the inter-trial interval in the cerebellum and underlays sequential effects in a Simon task. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 3H-thymidine labelling pattern of preleptotene chromosone condensation stages in the foetal sheep ovary

    International Nuclear Information System (INIS)

    Luciani, J.M.; Devictor-Vuillet, Monique; Bezard, Jacqueline; Mauleon, P.

    1979-01-01

    A sequence of morphological events from premeiotic interphase to leptotene has been described in the ovaries of 64-day old sheep foetuses. The nuclear changes throughout the condensation and decondensation stages showed a sequential pattern. After a flash of tritiated thymidine, the labelling pattern of these figures demonstrated that those stages followed premeiotic DNA synthesis, i.e. belonged to meiotic prophase. However, with our methodology, this sequence of morphological events could not be confirmed due to a high asynchronism in the oogenetic processes

  14. Adrenal vein sampling in primary aldosteronism: concordance of simultaneous vs sequential sampling.

    Science.gov (United States)

    Almarzooqi, Mohamed-Karji; Chagnon, Miguel; Soulez, Gilles; Giroux, Marie-France; Gilbert, Patrick; Oliva, Vincent L; Perreault, Pierre; Bouchard, Louis; Bourdeau, Isabelle; Lacroix, André; Therasse, Eric

    2017-02-01

    Many investigators believe that basal adrenal venous sampling (AVS) should be done simultaneously, whereas others opt for sequential AVS for simplicity and reduced cost. This study aimed to evaluate the concordance of sequential and simultaneous AVS methods. Between 1989 and 2015, bilateral simultaneous sets of basal AVS were obtained twice within 5 min, in 188 consecutive patients (59 women and 129 men; mean age: 53.4 years). Selectivity was defined by adrenal-to-peripheral cortisol ratio ≥2, and lateralization was defined as an adrenal aldosterone-to-cortisol ratio ≥2, the contralateral side. Sequential AVS was simulated using right sampling at -5 min (t = -5) and left sampling at 0 min (t = 0). There was no significant difference in mean selectivity ratio (P = 0.12 and P = 0.42 for the right and left sides respectively) and in mean lateralization ratio (P = 0.93) between t = -5 and t = 0. Kappa for selectivity between 2 simultaneous AVS was 0.71 (95% CI: 0.60-0.82), whereas it was 0.84 (95% CI: 0.76-0.92) and 0.85 (95% CI: 0.77-0.93) between sequential and simultaneous AVS at respectively -5 min and at 0 min. Kappa for lateralization between 2 simultaneous AVS was 0.84 (95% CI: 0.75-0.93), whereas it was 0.86 (95% CI: 0.78-0.94) and 0.80 (95% CI: 0.71-0.90) between sequential AVS and simultaneous AVS at respectively -5 min at 0 min. Concordance between simultaneous and sequential AVS was not different than that between 2 repeated simultaneous AVS in the same patient. Therefore, a better diagnostic performance is not a good argument to select the AVS method. © 2017 European Society of Endocrinology.

  15. Sequential motor skill: cognition, perception and action

    NARCIS (Netherlands)

    Ruitenberg, M.F.L.

    2013-01-01

    Discrete movement sequences are assumed to be the building blocks of more complex sequential actions that are present in our everyday behavior. The studies presented in this dissertation address the (neuro)cognitive underpinnings of such movement sequences, in particular in relationship to the role

  16. Improving the identification accuracy of senior witnesses: do prelineup questions and sequential testing help?

    Science.gov (United States)

    Memon, Amina; Gabbert, Fiona

    2003-04-01

    Eyewitness research has identified sequential lineup testing as a way of reducing false lineup choices while maintaining accurate identifications. The authors examined the usefulness of this procedure for reducing false choices in older adults. Young and senior witnesses viewed a crime video and were later presented with target present orabsent lineups in a simultaneous or sequential format. In addition, some participants received prelineup questions about their memory for a perpetrator's face and about their confidence in their ability to identify the culprit or to correctly reject the lineup. The sequential lineup reduced false choosing rates among young and older adults in target-absent conditions. In target-present conditions, sequential testing significantly reduced the correct identification rate in both age groups.

  17. Simultaneous versus Sequential Intratympanic Steroid Treatment for Severe-to-Profound Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Yoo, Myung Hoon; Lim, Won Sub; Park, Joo Hyun; Kwon, Joong Keun; Lee, Tae-Hoon; An, Yong-Hwi; Kim, Young-Jin; Kim, Jong Yang; Lim, Hyun Woo; Park, Hong Ju

    2016-01-01

    Severe-to-profound sudden sensorineural hearing loss (SSNHL) has a poor prognosis. We aimed to compare the efficacy of simultaneous and sequential oral and intratympanic steroids for this condition. Fifty patients with severe-to-profound SSNHL (>70 dB HL) were included from 7 centers. The simultaneous group (27 patients) received oral and intratympanic steroid injections for 2 weeks. The sequential group (23 patients) was treated with oral steroids for 2 weeks and intratympanic steroids for the subsequent 2 weeks. Pure-tone averages (PTA) and word discrimination scores (WDS) were compared before treatment and 2 weeks and 1 and 2 months after treatment. Treatment outcomes according to the modified American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria were also analyzed. The improvement in PTA and WDS at the 2-week follow-up was 23 ± 21 dB HL and 20 ± 39% in the simultaneous group and 31 ± 29 dB HL and 37 ± 42% in the sequential group; this was not statistically significant. Complete or partial recovery at the 2-week follow-up was observed in 26% of the simultaneous group and 30% of the sequential group; this was also not significant. The improvement in PTA and WDS at the 2-month follow-up was 40 ± 20 dB HL and 37 ± 35% in the simultaneous group and 41 ± 25 dB HL and 48 ± 41% in the sequential group; this was not statistically significant. Complete or partial recovery at the 2-month follow-up was observed in 33% of the simultaneous group and 35% of the sequential group; this was also not significant. Seven patients in the sequential group did not need intratympanic steroid injections for sufficient improvement after oral steroids alone. Simultaneous oral/intratympanic steroid treatment yielded a recovery similar to that produced by sequential treatment. Because the addition of intratympanic steroids can be decided upon based on the improvement after an oral steroid, the sequential regimen can be recommended to avoid unnecessary

  18. Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

    Directory of Open Access Journals (Sweden)

    Shigang Zhang

    2015-10-01

    Full Text Available Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics.

  19. Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

    Science.gov (United States)

    Zhang, Shigang; Song, Lijun; Zhang, Wei; Hu, Zheng; Yang, Yongmin

    2015-01-01

    Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics. PMID:26457709

  20. Inhibitory effect of sequential combined chemotherapy and radiotherapy on growth of implanted tumor in mice

    International Nuclear Information System (INIS)

    Okada, Kouji

    1983-01-01

    Sequential chemotherapy using FT-207, adriamycin and mitomycin C followed by radiotherapy was attempted to achieve effective inhibition against implanted tumor in C57BL/6 black mice bearing YM-12 tumors. Sequential combined chemotherapy was more effective than single drug chemotherapy or combined chemotherapy of other drugs. Addition of radiotherapy to the sequential combined chemotherapy was successful for enhancing therapeutic effect. (author)

  1. Structural and Functional Impacts of ER Coactivator Sequential Recruitment.

    Science.gov (United States)

    Yi, Ping; Wang, Zhao; Feng, Qin; Chou, Chao-Kai; Pintilie, Grigore D; Shen, Hong; Foulds, Charles E; Fan, Guizhen; Serysheva, Irina; Ludtke, Steven J; Schmid, Michael F; Hung, Mien-Chie; Chiu, Wah; O'Malley, Bert W

    2017-09-07

    Nuclear receptors recruit multiple coactivators sequentially to activate transcription. This "ordered" recruitment allows different coactivator activities to engage the nuclear receptor complex at different steps of transcription. Estrogen receptor (ER) recruits steroid receptor coactivator-3 (SRC-3) primary coactivator and secondary coactivators, p300/CBP and CARM1. CARM1 recruitment lags behind the binding of SRC-3 and p300 to ER. Combining cryo-electron microscopy (cryo-EM) structure analysis and biochemical approaches, we demonstrate that there is a close crosstalk between early- and late-recruited coactivators. The sequential recruitment of CARM1 not only adds a protein arginine methyltransferase activity to the ER-coactivator complex, it also alters the structural organization of the pre-existing ERE/ERα/SRC-3/p300 complex. It induces a p300 conformational change and significantly increases p300 HAT activity on histone H3K18 residues, which, in turn, promotes CARM1 methylation activity on H3R17 residues to enhance transcriptional activity. This study reveals a structural role for a coactivator sequential recruitment and biochemical process in ER-mediated transcription. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Sequential decay of Reggeons

    International Nuclear Information System (INIS)

    Yoshida, Toshihiro

    1981-01-01

    Probabilities of meson production in the sequential decay of Reggeons, which are formed from the projectile and the target in the hadron-hadron to Reggeon-Reggeon processes, are investigated. It is assumed that pair creation of heavy quarks and simultaneous creation of two antiquark-quark pairs are negligible. The leading-order terms with respect to ratio of creation probabilities of anti s s to anti u u (anti d d) are calculated. The production cross sections in the target fragmentation region are given in terms of probabilities in the initial decay of the Reggeons and an effect of manyparticle production. (author)

  3. [Professor GAO Yuchun's experience on "sequential acupuncture leads to smooth movement of qi"].

    Science.gov (United States)

    Wang, Yanjun; Xing, Xiao; Cui, Linhua

    2016-01-01

    Professor GAO Yuchun is considered as the key successor of GAO's academic school of acupuncture and moxibustion in Yanzhao region. Professor GAO's clinical experience of, "sequential acupuncture" is introduced in details in this article. In Professor GAO's opinions, appropriate acupuncture sequence is the key to satisfactory clinical effects during treatment. Based on different acupoints, sequential acupuncture can achieve the aim of qi following needles and needles leading qi; based on different symptoms, sequential acupuncture can regulate qi movement; based on different body positions, sequential acupuncture can harmonize qi-blood and reinforcing deficiency and reducing excess. In all, according to the differences of disease condition and constitution, based on the accurate acupoint selection and appropriate manipulation, it is essential to capture the nature of diseases and make the order of acupuncture, which can achieve the aim of regulating qi movement and reinforcing deficiency and reducing excess.

  4. Impact of controlling the sum of error probability in the sequential probability ratio test

    Directory of Open Access Journals (Sweden)

    Bijoy Kumarr Pradhan

    2013-05-01

    Full Text Available A generalized modified method is proposed to control the sum of error probabilities in sequential probability ratio test to minimize the weighted average of the two average sample numbers under a simple null hypothesis and a simple alternative hypothesis with the restriction that the sum of error probabilities is a pre-assigned constant to find the optimal sample size and finally a comparison is done with the optimal sample size found from fixed sample size procedure. The results are applied to the cases when the random variate follows a normal law as well as Bernoullian law.

  5. Characteristics of neutron-irradiated CR-39 foils treated by sequential chemical and electrochemical etching

    International Nuclear Information System (INIS)

    Somogyi, G.; Dajko, G.; Turek, K.; Spurny, F.

    1982-01-01

    The density of background spots revealed by chemical (CE) and electrochemical (ECE) etching and by their sequential application (CE + ECE) has been measured in several sorts of CR-39 material. The trends in the variation of sensitivity to Am-Be neutrons have been determined in CR-39 sheets covered by thick proton-radiator, when changing the field strength, frequency, etchant concentration, pre-etch duration and the fluence of neutrons. The results are analyzed in order to find out an optimum set of experimental parameters which may be proposed to attain high registration sensitivity to neutrons. (author)

  6. Mass-forming intrahepatic cholangiocarcinoma: Enhancement patterns in the arterial phase of dynamic hepatic CT - Correlation with clinicopathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Nobuhiro; Asayama, Yoshiki; Nishie, Akihiro; Ishigami, Kousei; Ushijima, Yasuhiro; Okamoto, Daisuke; Moirta, Koichiro; Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Takayama, Yukihisa [Kyushu University, Department of Radiology Informatics and Network, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Shirabe, Ken [Kyushu University, Department of Surgery and Science, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Aishima, Shinichi [Saga University Hospital, Department of Pathology and Microbiology, Faculty of Medicine, Saga City, Saga (Japan); Wang, Huanlin; Oda, Yoshinao [Kyushu University, Department of Anatomic Pathology, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan)

    2017-02-15

    To evaluate the relationship between the enhancement pattern of intrahepatic cholangiocarcinomas (ICCs) in the hepatic arterial phase (HAP) of dynamic hepatic CT and the clinicopathological findings with special reference to the perihilar type and the peripheral type. Forty-seven patients with pathologically proven ICCs were enrolled. Based on the enhancement pattern in the HAP, the lesions were classified into three groups: a hypovascular group (n=13), rim-enhancement group (n=18), and hypervascular group (n=16). The clinicopathological findings were compared among the three groups. Perihilar-type ICCs were significantly more frequently observed in the hypovascular group than in the rim-enhancement and hypervascular groups (p=0.006 and p <0.001, respectively). Lymphatic invasion, perineural invasion, and biliary invasion were significantly more frequent in the hypovascular group than the rim- enhancement group (p=0.001, p=0.025 and p=0.029, respectively) or hypervascular group (p <0.001, p <0.001 and p=0.025, respectively). Patients with hypovascular lesions showed significantly poorer disease-free survival than patients with rim-enhancing or hypervascular lesions (p=0.001 and p=0.001, respectively). Hypovascularity was an independent preoperative prognostic factor for disease-free survival (p<0.001). Hypovascular ICCs in the HAP tend to be of perihilar type and to have more malignant potential than other ICCs. (orig.)

  7. TELEGRAPHS TO INCANDESCENT LAMPS: A SEQUENTIAL PROCESS OF INNOVATION

    Directory of Open Access Journals (Sweden)

    Laurence J. Malone

    2000-01-01

    Full Text Available This paper outlines a sequential process of technological innovation in the emergence of the electrical industry in the United States from 1830 to 1880. Successive inventions that realize the commercial possibilities of electricity provided the foundation for an industry where technical knowledge, invention and diffusion were ultimately consolidated within the managerial structure of new firms. The genesis of the industry is traced, sequentially, through the development of the telegraph, arc light and incandescent lamp. Exploring the origins of the telegraph and incandescent lamp reveals a process where a series of inventions and firms result from successful efforts touse scientific principles to create new commodities and markets.

  8. Results of simultaneous and sequential pediatric liver and kidney transplantation.

    Science.gov (United States)

    Rogers, J; Bueno, J; Shapiro, R; Scantlebury, V; Mazariegos, G; Fung, J; Reyes, J

    2001-11-27

    The indications for simultaneous and sequential pediatric liver (LTx) and kidney (KTx) transplantation have not been well defined. We herein report the results of our experience with these procedures in children with end-stage liver disease and/or subsequent end-stage renal disease. Between 1984 and 1995, 12 LTx recipients received 15 kidney allografts. Eight simultaneous and seven sequential LTx/KTx were performed. There were six males and six females, with a mean age of 10.9 years (1.5-23.7). One of the eight simultaneous LTx/KTx was part of a multivisceral allograft. Five KTx were performed at varied intervals after successful LTx, one KTx was performed after a previous simultaneous LTx/KTx, and one KTx was performed after previous sequential LTx/KTx. Immunosuppression was with tacrolimus or cyclosporine and steroids. Indications for LTx were oxalosis (four), congenital hepatic fibrosis (two), cystinosis (one), polycystic liver disease (one), A-1-A deficiency (one), Total Parenteral Nutrition (TPN)-related (one), cryptogenic cirrhosis (one), and hepatoblastoma (one). Indications for KTx were oxalosis (four), drug-induced (four), polycystic kidney disease (three), cystinosis (one), and glomerulonephritis (1). With a mean follow-up of 58 months (0.9-130), the overall patient survival rate was 58% (7/12). One-year and 5-year actuarial patient survival rates were 66% and 58%, respectively. Patient survival rates at 1 year after KTx according to United Network of Organ Sharing (liver) status were 100% for status 3, 50% for status 2, and 0% for status 1. The overall renal allograft survival rate was 47%. Actuarial renal allograft survival rates were 53% at 1 and 5 years. The overall hepatic allograft survival rate was equivalent to the overall patient survival rate (58%). Six of seven surviving patients have normal renal allograft function, and one patient has moderate chronic allograft nephropathy. All surviving patients have normal hepatic allograft function. Six

  9. Transaction costs and sequential bargaining in transferable discharge permit markets.

    Science.gov (United States)

    Netusil, N R; Braden, J B

    2001-03-01

    Market-type mechanisms have been introduced and are being explored for various environmental programs. Several existing programs, however, have not attained the cost savings that were initially projected. Modeling that acknowledges the role of transactions costs and the discrete, bilateral, and sequential manner in which trades are executed should provide a more realistic basis for calculating potential cost savings. This paper presents empirical evidence on potential cost savings by examining a market for the abatement of sediment from farmland. Empirical results based on a market simulation model find no statistically significant change in mean abatement costs under several transaction cost levels when contracts are randomly executed. An alternative method of contract execution, gain-ranked, yields similar results. At the highest transaction cost level studied, trading reduces the total cost of compliance relative to a uniform standard that reflects current regulations.

  10. Multi-Stage Recognition of Speech Emotion Using Sequential Forward Feature Selection

    Directory of Open Access Journals (Sweden)

    Liogienė Tatjana

    2016-07-01

    Full Text Available The intensive research of speech emotion recognition introduced a huge collection of speech emotion features. Large feature sets complicate the speech emotion recognition task. Among various feature selection and transformation techniques for one-stage classification, multiple classifier systems were proposed. The main idea of multiple classifiers is to arrange the emotion classification process in stages. Besides parallel and serial cases, the hierarchical arrangement of multi-stage classification is most widely used for speech emotion recognition. In this paper, we present a sequential-forward-feature-selection-based multi-stage classification scheme. The Sequential Forward Selection (SFS and Sequential Floating Forward Selection (SFFS techniques were employed for every stage of the multi-stage classification scheme. Experimental testing of the proposed scheme was performed using the German and Lithuanian emotional speech datasets. Sequential-feature-selection-based multi-stage classification outperformed the single-stage scheme by 12–42 % for different emotion sets. The multi-stage scheme has shown higher robustness to the growth of emotion set. The decrease in recognition rate with the increase in emotion set for multi-stage scheme was lower by 10–20 % in comparison with the single-stage case. Differences in SFS and SFFS employment for feature selection were negligible.

  11. Loss pattern identification in near-real-time accounting systems

    International Nuclear Information System (INIS)

    Argentesi, F.

    1983-01-01

    To maximize the benefits from an advanced safeguards technique such as near-real-time accounting, sophisticated methods of analysing sequential material accounting data are necessary. The methods must be capable of controlling the overall false-alarm rate while assuring good power of detection against all possible diversion scenarios. A method drawn from the field of pattern recognition and related to the alarm-sequence chart appears to be promising. Power curves based on Monte Carlo calculations illustrate the improvements over more conventional methods. (author)

  12. Polytypic pattern matching

    NARCIS (Netherlands)

    Jeuring, J.T.

    1995-01-01

    The pattern matching problem can be informally specified as follows: given a pattern and a text, find all occurrences of the pattern in the text. The pattern and the text may both be lists, or they may both be trees, or they may both be multi-dimensional arrays, etc. This paper describes a general

  13. New findings for maternal mortality age patterns: aggregated results for 38 countries.

    Directory of Open Access Journals (Sweden)

    Ann K Blanc

    Full Text Available With recent results showing a global decline in overall maternal mortality during the last two decades and with the target date for achieving the Millennium Development Goals only four years away, the question of how to continue or even accelerate the decline has become more pressing. By knowing where the risk is highest as well as where the numbers of deaths are greatest, it may be possible to re-direct resources and fine-tune strategies for greater effectiveness in efforts to reduce maternal mortality.We aggregate data from 38 Demographic and Health Surveys that included a maternal mortality module and were conducted in 2000 or later to produce maternal mortality ratios, rates, and numbers of deaths by five year age groups, separately by residence, region, and overall mortality level.The age pattern of maternal mortality is broadly similar across regions, type of place of residence, and overall level of maternal mortality. A "J" shaped curve, with markedly higher risk after age 30, is evident in all groups. We find that the excess risk among adolescents is of a much lower magnitude than is generally assumed. The oldest age groups appear to be especially resistant to change. We also find evidence of extremely elevated risk among older mothers in countries with high levels of HIV prevalence.The largest number of deaths occurs in the age groups from 20-34, largely because those are the ages at which women are most likely to give birth so efforts directed at this group would most effectively reduce the number of deaths. Yet equity considerations suggest that efforts also be directed toward those most at risk, i.e., older women and adolescents. Because women are at risk each time they become pregnant, fulfilling the substantial unmet need for contraception is a cross-cutting strategy that can address both effectiveness and equity concerns.

  14. Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation.

    Science.gov (United States)

    Ramakers, Geerte G J; Kraaijenga, Véronique J C; Smulders, Yvette E; van Zon, Alice; Stegeman, Inge; Stokroos, Robert J; Free, Rolien H; Frijns, Johan H M; Huinck, Wendy J; Van Zanten, Gijsbert A; Grolman, Wilko

    2017-01-01

    There is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus. To investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years). This study is a secondary analysis as part of a multicenter randomized controlled trial. Thirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs) because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI) and Tinnitus Questionnaire (TQ). The prevalence of preoperative tinnitus was 42% (16/38). One year after bilateral implantation, there was a median difference of -8 (inter-quartile range (IQR): -28 to 4) in THI score and -9 (IQR: -17 to -9) in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group, four patients had an additional benefit of the second CI: a total

  15. Learning sequential control in a Neural Blackboard Architecture for in situ concept reasoning

    NARCIS (Netherlands)

    van der Velde, Frank; van der Velde, Frank; Besold, Tarek R.; Lamb, Luis; Serafini, Luciano; Tabor, Whitney

    2016-01-01

    Simulations are presented and discussed of learning sequential control in a Neural Blackboard Architecture (NBA) for in situ concept-based reasoning. Sequential control is learned in a reservoir network, consisting of columns with neural circuits. This allows the reservoir to control the dynamics of

  16. Microstructural evolution of reduced-activation martensitic steel under single and sequential ion irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Fengfeng [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Guo, Liping, E-mail: guolp@whu.edu.cn [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Jin, Shuoxue; Li, Tiecheng; Zheng, Zhongcheng [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Yang, Feng; Xiong, Xuesong; Suo, Jinping [State Key Laboratory of Mould Technology, Institute of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2013-07-15

    Microstructural evolution of super-clean reduced-activation martensitic steels irradiated with single-beam (Fe{sup +}) and sequential-beam (Fe{sup +} plus He{sup +}) at 350 °C and 550 °C was studied. Sequential-beam irradiation induced smaller size and larger number density of precipitates compared to single-beam irradiation at 350 °C. The largest size of cavities was observed after sequential-beam irradiation at 550 °C. The segregation of Cr and W and depletion of Fe in carbides were observed, and the maximum depletion of Fe and enrichment of Cr occurred under irradiation at 350 °C.

  17. Sequential and Simultaneous Logit: A Nested Model.

    NARCIS (Netherlands)

    van Ophem, J.C.M.; Schram, A.J.H.C.

    1997-01-01

    A nested model is presented which has both the sequential and the multinomial logit model as special cases. This model provides a simple test to investigate the validity of these specifications. Some theoretical properties of the model are discussed. In the analysis a distribution function is

  18. Truly costly sequential search and oligopolistic pricing

    NARCIS (Netherlands)

    Janssen, Maarten C W; Moraga-González, José Luis; Wildenbeest, Matthijs R.

    We modify the paper of Stahl (1989) [Stahl, D.O., 1989. Oligopolistic pricing with sequential consumer search. American Economic Review 79, 700-12] by relaxing the assumption that consumers obtain the first price quotation for free. When all price quotations are costly to obtain, the unique

  19. Making Career Decisions--A Sequential Elimination Approach.

    Science.gov (United States)

    Gati, Itamar

    1986-01-01

    Presents a model for career decision making based on the sequential elimination of occupational alternatives, an adaptation for career decisions of Tversky's (1972) elimination-by-aspects theory of choice. The expected utility approach is reviewed as a representative compensatory model for career decisions. Advantages, disadvantages, and…

  20. Sequential Computerized Mastery Tests--Three Simulation Studies

    Science.gov (United States)

    Wiberg, Marie

    2006-01-01

    A simulation study of a sequential computerized mastery test is carried out with items modeled with the 3 parameter logistic item response theory model. The examinees' responses are either identically distributed, not identically distributed, or not identically distributed together with estimation errors in the item characteristics. The…

  1. Sequential Low Cost Interventions Double Hand Hygiene Rates ...

    African Journals Online (AJOL)

    Sequential Low Cost Interventions Double Hand Hygiene Rates Among Medical Teams in a Resource Limited Setting. Results of a Hand Hygiene Quality Improvement Project Conducted At University Teaching Hospital of Kigali (Chuk), Kigali, Rwanda.

  2. One-pot growth of two-dimensional lateral heterostructures via sequential edge-epitaxy

    Science.gov (United States)

    Sahoo, Prasana K.; Memaran, Shahriar; Xin, Yan; Balicas, Luis; Gutiérrez, Humberto R.

    2018-01-01

    Two-dimensional heterojunctions of transition-metal dichalcogenides have great potential for application in low-power, high-performance and flexible electro-optical devices, such as tunnelling transistors, light-emitting diodes, photodetectors and photovoltaic cells. Although complex heterostructures have been fabricated via the van der Waals stacking of different two-dimensional materials, the in situ fabrication of high-quality lateral heterostructures with multiple junctions remains a challenge. Transition-metal-dichalcogenide lateral heterostructures have been synthesized via single-step, two-step or multi-step growth processes. However, these methods lack the flexibility to control, in situ, the growth of individual domains. In situ synthesis of multi-junction lateral heterostructures does not require multiple exchanges of sources or reactors, a limitation in previous approaches as it exposes the edges to ambient contamination, compromises the homogeneity of domain size in periodic structures, and results in long processing times. Here we report a one-pot synthetic approach, using a single heterogeneous solid source, for the continuous fabrication of lateral multi-junction heterostructures consisting of monolayers of transition-metal dichalcogenides. The sequential formation of heterojunctions is achieved solely by changing the composition of the reactive gas environment in the presence of water vapour. This enables selective control of the water-induced oxidation and volatilization of each transition-metal precursor, as well as its nucleation on the substrate, leading to sequential edge-epitaxy of distinct transition-metal dichalcogenides. Photoluminescence maps confirm the sequential spatial modulation of the bandgap, and atomic-resolution images reveal defect-free lateral connectivity between the different transition-metal-dichalcogenide domains within a single crystal structure. Electrical transport measurements revealed diode-like responses across the

  3. Sequential optimization of matrix chain multiplication relative to different cost functions

    KAUST Repository

    Chikalov, Igor; Hussain, Shahid; Moshkov, Mikhail

    2011-01-01

    In this paper, we present a methodology to optimize matrix chain multiplication sequentially relative to different cost functions such as total number of scalar multiplications, communication overhead in a multiprocessor environment, etc. For n matrices our optimization procedure requires O(n 3) arithmetic operations per one cost function. This work is done in the framework of a dynamic programming extension that allows sequential optimization relative to different criteria. © 2011 Springer-Verlag Berlin Heidelberg.

  4. Three-dimensional classical-ensemble modeling of non-sequential double ionization

    International Nuclear Information System (INIS)

    Haan, S.L.; Breen, L.; Tannor, D.; Panfili, R.; Ho, Phay J.; Eberly, J.H.

    2005-01-01

    Full text: We have been using 1d ensembles of classical two-electron atoms to simulate helium atoms that are exposed to pulses of intense laser radiation. In this talk we discuss the challenges in setting up a 3d classical ensemble that can mimic the quantum ground state of helium. We then report studies in which each one of 500,000 two-electron trajectories is followed in 3d through a ten-cycle (25 fs) 780 nm laser pulse. We examine double-ionization yield for various intensities, finding the familiar knee structure. We consider the momentum spread of outcoming electrons in directions both parallel and perpendicular to the direction of laser polarization, and find results that are consistent with experiment. We examine individual trajectories and recollision processes that lead to double ionization, considering the best phases of the laser cycle for recollision events and looking at the possible time delay between recollision and emergence. We consider also the number of recollision events, and find that multiple recollisions are common in the classical ensemble. We investigate which collisional processes lead to various final electron momenta. We conclude with comments regarding the ability of classical mechanics to describe non-sequential double ionization, and a quick summary of similarities and differences between 1d and 3d classical double ionization using energy-trajectory comparisons. Refs. 3 (author)

  5. Direct methods and residue type specific isotope labeling in NMR structure determination and model-driven sequential assignment

    International Nuclear Information System (INIS)

    Schedlbauer, Andreas; Auer, Renate; Ledolter, Karin; Tollinger, Martin; Kloiber, Karin; Lichtenecker, Roman; Ruedisser, Simon; Hommel, Ulrich; Schmid, Walther; Konrat, Robert; Kontaxis, Georg

    2008-01-01

    Direct methods in NMR based structure determination start from an unassigned ensemble of unconnected gaseous hydrogen atoms. Under favorable conditions they can produce low resolution structures of proteins. Usually a prohibitively large number of NOEs is required, to solve a protein structure ab-initio, but even with a much smaller set of distance restraints low resolution models can be obtained which resemble a protein fold. One problem is that at such low resolution and in the absence of a force field it is impossible to distinguish the correct protein fold from its mirror image. In a hybrid approach these ambiguous models have the potential to aid in the process of sequential backbone chemical shift assignment when 13 C β and 13 C' shifts are not available for sensitivity reasons. Regardless of the overall fold they enhance the information content of the NOE spectra. These, combined with residue specific labeling and minimal triple-resonance data using 13 C α connectivity can provide almost complete sequential assignment. Strategies for residue type specific labeling with customized isotope labeling patterns are of great advantage in this context. Furthermore, this approach is to some extent error-tolerant with respect to data incompleteness, limited precision of the peak picking, and structural errors caused by misassignment of NOEs

  6. Income and children's behavioral functioning: a sequential mediation analysis.

    Science.gov (United States)

    Shelleby, Elizabeth C; Votruba-Drzal, Elizabeth; Shaw, Daniel S; Dishion, Thomas J; Wilson, Melvin N; Gardner, Frances

    2014-12-01

    Children from low-income households tend to exhibit higher levels of conduct problems and emotional problems, yet the pathways linking economic disadvantage to children's behavioral functioning are not well understood. This study uses data from the Early Steps Multisite (ESM) project (N = 731) to investigate associations between family income in early childhood and children's conduct problems and emotional problems in middle childhood. The study explores whether the associations from income to child conduct problems and emotional problems operate through maternal depressive symptoms and 3 family risk factors in early childhood-harsh parenting, parenting hassles, and chaos in the home environment. Results of a sequential mediation model revealed significant indirect effects of family income on children's conduct problems operating through maternal depressive symptoms and parenting hassles and indirect effects of family income on children's emotional problems operating through maternal depressive symptoms, chaos in the home environment, and parenting hassles. Implications of these findings for understanding processes through which income influences child functioning are discussed.

  7. Two-step sequential pretreatment for the enhanced enzymatic hydrolysis of coffee spent waste.

    Science.gov (United States)

    Ravindran, Rajeev; Jaiswal, Swarna; Abu-Ghannam, Nissreen; Jaiswal, Amit K

    2017-09-01

    In the present study, eight different pretreatments of varying nature (physical, chemical and physico-chemical) followed by a sequential, combinatorial pretreatment strategy was applied to spent coffee waste to attain maximum sugar yield. Pretreated samples were analysed for total reducing sugar, individual sugars and generation of inhibitory compounds such as furfural and hydroxymethyl furfural (HMF) which can hinder microbial growth and enzyme activity. Native spent coffee waste was high in hemicellulose content. Galactose was found to be the predominant sugar in spent coffee waste. Results showed that sequential pretreatment yielded 350.12mg of reducing sugar/g of substrate, which was 1.7-fold higher than in native spent coffee waste (203.4mg/g of substrate). Furthermore, extensive delignification was achieved using sequential pretreatment strategy. XRD, FTIR, and DSC profiles of the pretreated substrates were studied to analyse the various changes incurred in sequentially pretreated spent coffee waste as opposed to native spent coffee waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Competitive interactions affect working memory performance for both simultaneous and sequential stimulus presentation.

    Science.gov (United States)

    Ahmad, Jumana; Swan, Garrett; Bowman, Howard; Wyble, Brad; Nobre, Anna C; Shapiro, Kimron L; McNab, Fiona

    2017-07-06

    Competition between simultaneously presented visual stimuli lengthens reaction time and reduces both the BOLD response and neural firing. In contrast, conditions of sequential presentation have been assumed to be free from competition. Here we manipulated the spatial proximity of stimuli (Near versus Far conditions) to examine the effects of simultaneous and sequential competition on different measures of working memory (WM) for colour. With simultaneous presentation, the measure of WM precision was significantly lower for Near items, and participants reported the colour of the wrong item more often. These effects were preserved when the second stimulus immediately followed the first, disappeared when they were separated by 500 ms, and were partly recovered (evident for our measure of mis-binding but not WM precision) when the task was altered to encourage participants to maintain the sequentially presented items together in WM. Our results show, for the first time, that competition affects the measure of WM precision, and challenge the assumption that sequential presentation removes competition.

  9. Radiologic findings of primary pneumonia in children

    International Nuclear Information System (INIS)

    Song, Chi Sung; Kim, In One; Yeon, Kyung Mo

    1991-01-01

    It is not always easy to detect and interpret radiologic findings of pediatric pneumonia. Authors retrospectively analysed radiologic findings of 102 cases of pediatric primary pneumonia treated at Yeong-Deung-Po City Hospital between 1988 and 1990 to understand the past trend of radiologic pattern and to attain helpful information in diagnosing pediatric pneumonia hereafter. Results were as follows. Positive radiologic findings were noted in 85 cases (84%), but 17 cases (16%) showed indefinite lesion. The cases of infantile pneumonia (under 1 year of age) were 44. The most frequent finding was bilateral peribronchial infiltration with overearation (21 cases, 48%), followed by multiple patchy atelectasis associated with the findings of bilateral peribronchial infiltration and overaeration (nine cases, 23%), peribronchial infiltration without definite overaeration (six cases, 14%), alveolar consolidation superimposed on the peribronchial infiltration (three cases, 6%), alveolar consolidation (three cases, 6%) and bronchopneumonic pattern (two cases, 4%). The cases of pre-school age (1-5 years of age) were 34. Bilateral parahilar peribronchial infiltration was the most frequent finding (24 cases, 71%), followed by alveolar consolidation (six cases, 17%) and bronchopneumonic pattern (four cases, 12%). The cases of school age (over 6 years of age) were seven. Six cases (85%) showed alveolar consolidation and one case (15%) showed bronchopneumonic pattern. In short, the younger the patient was, the more frequently the interstitial infiltration occurred. Furthermore, overaeration and patchy atelectasis were unique findings of infantile pneumonia. After the school age, the pattern of pneumonia became similar to that of adults

  10. Interpretability degrees of finitely axiomatized sequential theories

    NARCIS (Netherlands)

    Visser, Albert

    In this paper we show that the degrees of interpretability of finitely axiomatized extensions-in-the-same-language of a finitely axiomatized sequential theory-like Elementary Arithmetic EA, IΣ1, or the Gödel-Bernays theory of sets and classes GB-have suprema. This partially answers a question posed

  11. Interpretability Degrees of Finitely Axiomatized Sequential Theories

    NARCIS (Netherlands)

    Visser, Albert

    2012-01-01

    In this paper we show that the degrees of interpretability of finitely axiomatized extensions-in-the-same-language of a finitely axiomatized sequential theory —like Elementary Arithmetic EA, IΣ1, or the Gödel-Bernays theory of sets and classes GB— have suprema. This partially answers a question

  12. Adult Word Recognition and Visual Sequential Memory

    Science.gov (United States)

    Holmes, V. M.

    2012-01-01

    Two experiments were conducted investigating the role of visual sequential memory skill in the word recognition efficiency of undergraduate university students. Word recognition was assessed in a lexical decision task using regularly and strangely spelt words, and nonwords that were either standard orthographically legal strings or items made from…

  13. Applying Learning Analytics to Explore the Effects of Motivation on Online Students' Reading Behavioral Patterns

    Science.gov (United States)

    Sun, Jerry Chih-Yuan; Lin, Che-Tsun; Chou, Chien

    2018-01-01

    This study aims to apply a sequential analysis to explore the effect of learning motivation on online reading behavioral patterns. The study's participants consisted of 160 graduate students who were classified into three group types: low reading duration with low motivation, low reading duration with high motivation, and high reading duration…

  14. Growth patterns of an intertidal gastropod as revealed by oxygen isotope analysis

    Science.gov (United States)

    Bean, J. R.; Hill, T. M.; Guerra, C.

    2007-12-01

    The size and morphology of mollusk shells are affected by environmental conditions. As a result, it is difficult to assess growth rate, population age structure, shell morphologies associated with ontogenetic stages, and to compare life history patterns across various environments. Oxygen isotope analysis is a useful tool for estimating minimum ages and growth rates of calcium carbonate secreting organisms. Calcite shell material from members of two northern California populations of the intertidal muricid gastropod Acanthinucella spirata was sampled for isotopic analysis. Individual shells were sampled from apex to margin, thus providing a sequential record of juvenile and adult growth. A. spirata were collected from a sheltered habitat in Tomales Bay and from an exposed reef in Bolinas. Abiotic factors, such as temperature, wave exposure, and substrate consistency, and biotic composition differ significantly between these sites, possibly resulting in local adaptations and variation in life history and growth patterns. Shell morphology of A. spirata changes with age as internal shell margin thickenings of denticle rows associated with external growth bands are irregularly accreted. It is not known when, either seasonally and/or ontogentically, these thickenings and bands form or whether inter or intra-populational variation exists. Preliminary results demonstrate the seasonal oxygen isotopic variability present at the two coastal sites, indicating 5-6 degC changes from winter to summertime temperatures; these data are consistent with local intertidal temperature records. Analysis of the seasonal patterns indicate that: 1) differences in growth rate and seasonal growth patterns at different ontogenetic stages within populations, and 2) differences in growth patterns and possibly age structure between the two A. spirata populations. These findings indicate that isotopic analyses, in addition to field observations and morphological measurements, are necessary to

  15. How Do Children Deal With Conflict? A Developmental Study of Sequential Conflict Modulation

    Directory of Open Access Journals (Sweden)

    Silvan F. A. Smulders

    2018-05-01

    Full Text Available This study examined age-related differences in sequential conflict modulation (SCM, elicited in three tasks requiring the inhibition of pre-potent responses; a Simon task, an S-R compatibility (SRC task and a hybrid Choice-reaction/NoGo task. The primary focus was on age-related changes in performance changes following a conflict trial. A secondary aim was to assess whether SCM follows different developmental trajectories depending on the type of conflict elicited by the tasks. The tasks were presented to three different groups of participants with an age range between 7- to 25-years—one group of participants for each task. For each task, the response-to-stimulus interval (RSI was manipulated (50 vs. 500 ms across trial blocks to assess time-dependent changes in conflict modulation. The results showed SCM for all three tasks, although the specific patterns differed between tasks and RSIs. Importantly, the magnitude of SCM decreased with advancing age, but this developmental trend did not survive when considering age-group differences in basic response speed. The current results contribute to the emerging evidence suggesting that patterns of SCM are task specific and were interpreted in terms of multiple bottom-up control mechanisms.

  16. The subtyping of primary aldosteronism by adrenal vein sampling: sequential blood sampling causes factitious lateralization.

    Science.gov (United States)

    Rossitto, Giacomo; Battistel, Michele; Barbiero, Giulio; Bisogni, Valeria; Maiolino, Giuseppe; Diego, Miotto; Seccia, Teresa M; Rossi, Gian Paolo

    2018-02-01

    The pulsatile secretion of adrenocortical hormones and a stress reaction occurring when starting adrenal vein sampling (AVS) can affect the selectivity and also the assessment of lateralization when sequential blood sampling is used. We therefore tested the hypothesis that a simulated sequential blood sampling could decrease the diagnostic accuracy of lateralization index for identification of aldosterone-producing adenoma (APA), as compared with bilaterally simultaneous AVS. In 138 consecutive patients who underwent subtyping of primary aldosteronism, we compared the results obtained simultaneously bilaterally when starting AVS (t-15) and 15 min after (t0), with those gained with a simulated sequential right-to-left AVS technique (R ⇒ L) created by combining hormonal values obtained at t-15 and at t0. The concordance between simultaneously obtained values at t-15 and t0, and between simultaneously obtained values and values gained with a sequential R ⇒ L technique, was also assessed. We found a marked interindividual variability of lateralization index values in the patients with bilaterally selective AVS at both time point. However, overall the lateralization index simultaneously determined at t0 provided a more accurate identification of APA than the simulated sequential lateralization indexR ⇒ L (P = 0.001). Moreover, regardless of which side was sampled first, the sequential AVS technique induced a sequence-dependent overestimation of lateralization index. While in APA patients the concordance between simultaneous AVS at t0 and t-15 and between simultaneous t0 and sequential technique was moderate-to-good (K = 0.55 and 0.66, respectively), in non-APA patients, it was poor (K = 0.12 and 0.13, respectively). Sequential AVS generates factitious between-sides gradients, which lower its diagnostic accuracy, likely because of the stress reaction arising upon starting AVS.

  17. Effects of neostriatal 6-OHDA lesion on performance in a rat sequential reaction time task.

    Science.gov (United States)

    Domenger, D; Schwarting, R K W

    2008-10-31

    Work in humans and monkeys has provided evidence that the basal ganglia, and the neurotransmitter dopamine therein, play an important role for sequential learning and performance. Compared to primates, experimental work in rodents is rather sparse, largely due to the fact that tasks comparable to the human ones, especially serial reaction time tasks (SRTT), had been lacking until recently. We have developed a rat model of the SRTT, which allows to study neural correlates of sequential performance and motor sequence execution. Here, we report the effects of dopaminergic neostriatal lesions, performed using bilateral 6-hydroxydopamine injections, on performance of well-trained rats tested in our SRTT. Sequential behavior was measured in two ways: for one, the effects of small violations of otherwise well trained sequences were examined as a measure of attention and automation. Secondly, sequential versus random performance was compared as a measure of sequential learning. Neurochemically, the lesions led to sub-total dopamine depletions in the neostriatum, which ranged around 60% in the lateral, and around 40% in the medial neostriatum. These lesions led to a general instrumental impairment in terms of reduced speed (response latencies) and response rate, and these deficits were correlated with the degree of striatal dopamine loss. Furthermore, the violation test indicated that the lesion group conducted less automated responses. The comparison of random versus sequential responding showed that the lesion group did not retain its superior sequential performance in terms of speed, whereas they did in terms of accuracy. Also, rats with lesions did not improve further in overall performance as compared to pre-lesion values, whereas controls did. These results support previous results that neostriatal dopamine is involved in instrumental behaviour in general. Also, these lesions are not sufficient to completely abolish sequential performance, at least when acquired

  18. Sequential mediating effects of provided and received social support on trait emotional intelligence and subjective happiness: A longitudinal examination in Hong Kong Chinese university students.

    Science.gov (United States)

    Ye, Jiawen; Yeung, Dannii Y; Liu, Elaine S C; Rochelle, Tina L

    2018-04-03

    Past research has often focused on the effects of emotional intelligence and received social support on subjective well-being yet paid limited attention to the effects of provided social support. This study adopted a longitudinal design to examine the sequential mediating effects of provided and received social support on the relationship between trait emotional intelligence and subjective happiness. A total of 214 Hong Kong Chinese undergraduates were asked to complete two assessments with a 6-month interval in between. The results of the sequential mediation analysis indicated that the trait emotional intelligence measured in Time 1 indirectly influenced the level of subjective happiness in Time 2 through a sequential pathway of social support provided for others in Time 1 and social support received from others in Time 2. These findings highlight the importance of trait emotional intelligence and the reciprocal exchanges of social support in the subjective well-being of university students. © 2018 International Union of Psychological Science.

  19. CRISPR/Cas9-mediated gene targeting in Arabidopsis using sequential transformation.

    Science.gov (United States)

    Miki, Daisuke; Zhang, Wenxin; Zeng, Wenjie; Feng, Zhengyan; Zhu, Jian-Kang

    2018-05-17

    Homologous recombination-based gene targeting is a powerful tool for precise genome modification and has been widely used in organisms ranging from yeast to higher organisms such as Drosophila and mouse. However, gene targeting in higher plants, including the most widely used model plant Arabidopsis thaliana, remains challenging. Here we report a sequential transformation method for gene targeting in Arabidopsis. We find that parental lines expressing the bacterial endonuclease Cas9 from the egg cell- and early embryo-specific DD45 gene promoter can improve the frequency of single-guide RNA-targeted gene knock-ins and sequence replacements via homologous recombination at several endogenous sites in the Arabidopsis genome. These heritable gene targeting can be identified by regular PCR. Our approach enables routine and fine manipulation of the Arabidopsis genome.

  20. The Dietary Patterns Methods Project: Synthesis of Findings across Cohorts and Relevance to Dietary Guidance1234

    Science.gov (United States)

    Liese, Angela D; Krebs-Smith, Susan M; Subar, Amy F; George, Stephanie M; Harmon, Brook E; Neuhouser, Marian L; Boushey, Carol J; Schap, TusaRebecca E; Reedy, Jill

    2015-01-01

    The Dietary Patterns Methods Project (DPMP) was initiated in 2012 to strengthen research evidence on dietary indices, dietary patterns, and health for upcoming revisions of the Dietary Guidelines for Americans, given that the lack of consistent methodology has impeded development of consistent and reliable conclusions. DPMP investigators developed research questions and a standardized approach to index-based dietary analysis. This article presents a synthesis of findings across the cohorts. Standardized analyses were conducted in the NIH-AARP Diet and Health Study, the Multiethnic Cohort, and the Women’s Health Initiative Observational Study (WHI-OS). Healthy Eating Index 2010, Alternative Healthy Eating Index 2010 (AHEI-2010), alternate Mediterranean Diet, and Dietary Approaches to Stop Hypertension (DASH) scores were examined across cohorts for correlations between pairs of indices; concordant classifications into index score quintiles; associations with all-cause, cardiovascular disease (CVD), and cancer mortality with the use of Cox proportional hazards models; and dietary intake of foods and nutrients corresponding to index quintiles. Across all cohorts in women and men, there was a high degree of correlation and consistent classifications between index pairs. Higher diet quality (top quintile) was significantly and consistently associated with an 11–28% reduced risk of death due to all causes, CVD, and cancer compared with the lowest quintile, independent of known confounders. This was true for all diet index–mortality associations, with the exception of AHEI-2010 and cancer mortality in WHI-OS women. In all cohorts, survival benefit was greater with a higher-quality diet, and relatively small intake differences distinguished the index quintiles. The reductions in mortality risk started at relatively lower levels of diet quality. Higher scores on each of the indices, signifying higher diet quality, were associated with marked reductions in mortality

  1. Eyewitness identification in simultaneous and sequential lineups: an investigation of position effects using receiver operating characteristics.

    Science.gov (United States)

    Meisters, Julia; Diedenhofen, Birk; Musch, Jochen

    2018-04-20

    For decades, sequential lineups have been considered superior to simultaneous lineups in the context of eyewitness identification. However, most of the research leading to this conclusion was based on the analysis of diagnosticity ratios that do not control for the respondent's response criterion. Recent research based on the analysis of ROC curves has found either equal discriminability for sequential and simultaneous lineups, or higher discriminability for simultaneous lineups. Some evidence for potential position effects and for criterion shifts in sequential lineups has also been reported. Using ROC curve analysis, we investigated the effects of the suspect's position on discriminability and response criteria in both simultaneous and sequential lineups. We found that sequential lineups suffered from an unwanted position effect. Respondents employed a strict criterion for the earliest lineup positions, and shifted to a more liberal criterion for later positions. No position effects and no criterion shifts were observed in simultaneous lineups. This result suggests that sequential lineups are not superior to simultaneous lineups, and may give rise to unwanted position effects that have to be considered when conducting police lineups.

  2. Hemodynamic analysis of sequential graft from right coronary system to left coronary system.

    Science.gov (United States)

    Wang, Wenxin; Mao, Boyan; Wang, Haoran; Geng, Xueying; Zhao, Xi; Zhang, Huixia; Xie, Jinsheng; Zhao, Zhou; Lian, Bo; Liu, Youjun

    2016-12-28

    Sequential and single grafting are two surgical procedures of coronary artery bypass grafting. However, it remains unclear if the sequential graft can be used between the right and left coronary artery system. The purpose of this paper is to clarify the possibility of right coronary artery system anastomosis to left coronary system. A patient-specific 3D model was first reconstructed based on coronary computed tomography angiography (CCTA) images. Two different grafts, the normal multi-graft (Model 1) and the novel multi-graft (Model 2), were then implemented on this patient-specific model using virtual surgery techniques. In Model 1, the single graft was anastomosed to right coronary artery (RCA) and the sequential graft was adopted to anastomose left anterior descending (LAD) and left circumflex artery (LCX). While in Model 2, the single graft was anastomosed to LAD and the sequential graft was adopted to anastomose RCA and LCX. A zero-dimensional/three-dimensional (0D/3D) coupling method was used to realize the multi-scale simulation of both the pre-operative and two post-operative models. Flow rates in the coronary artery and grafts were obtained. The hemodynamic parameters were also showed, including wall shear stress (WSS) and oscillatory shear index (OSI). The area of low WSS and OSI in Model 1 was much less than that in Model 2. Model 1 shows optimistic hemodynamic modifications which may enhance the long-term patency of grafts. The anterior segments of sequential graft have better long-term patency than the posterior segments. With rational spatial position of the heart vessels, the last anastomosis of sequential graft should be connected to the main branch.

  3. Sequential test procedures for inventory differences

    International Nuclear Information System (INIS)

    Goldman, A.S.; Kern, E.A.; Emeigh, C.W.

    1985-01-01

    By means of a simulation study, we investigated the appropriateness of Page's and power-one sequential tests on sequences of inventory differences obtained from an example materials control unit, a sub-area of a hypothetical UF 6 -to-U 3 O 8 conversion process. The study examined detection probability and run length curves obtained from different loss scenarios. 12 refs., 10 figs., 2 tabs

  4. The effects of sequential attention shifts within visual working memory.

    Science.gov (United States)

    Li, Qi; Saiki, Jun

    2014-01-01

    Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM) representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: (1) orienting attention to one location, and then withdrawing attention from it, and (2) switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed equivalent benefits of the first and second spatial cues, suggesting that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first-cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance was still better at first-cued locations than at uncued and neutral locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance.

  5. The effects of sequential attention shifts within visual working memory

    Science.gov (United States)

    Li, Qi; Saiki, Jun

    2014-01-01

    Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM) representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: (1) orienting attention to one location, and then withdrawing attention from it, and (2) switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed equivalent benefits of the first and second spatial cues, suggesting that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first-cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance was still better at first-cued locations than at uncued and neutral locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance. PMID:25237306

  6. Regularized principal covariates regression and its application to finding coupled patterns in climate fields

    Science.gov (United States)

    Fischer, M. J.

    2014-02-01

    There are many different methods for investigating the coupling between two climate fields, which are all based on the multivariate regression model. Each different method of solving the multivariate model has its own attractive characteristics, but often the suitability of a particular method for a particular problem is not clear. Continuum regression methods search the solution space between the conventional methods and thus can find regression model subspaces that mix the attractive characteristics of the end-member subspaces. Principal covariates regression is a continuum regression method that is easily applied to climate fields and makes use of two end-members: principal components regression and redundancy analysis. In this study, principal covariates regression is extended to additionally span a third end-member (partial least squares or maximum covariance analysis). The new method, regularized principal covariates regression, has several attractive features including the following: it easily applies to problems in which the response field has missing values or is temporally sparse, it explores a wide range of model spaces, and it seeks a model subspace that will, for a set number of components, have a predictive skill that is the same or better than conventional regression methods. The new method is illustrated by applying it to the problem of predicting the southern Australian winter rainfall anomaly field using the regional atmospheric pressure anomaly field. Regularized principal covariates regression identifies four major coupled patterns in these two fields. The two leading patterns, which explain over half the variance in the rainfall field, are related to the subtropical ridge and features of the zonally asymmetric circulation.

  7. Plasmon-driven sequential chemical reactions in an aqueous environment.

    Science.gov (United States)

    Zhang, Xin; Wang, Peijie; Zhang, Zhenglong; Fang, Yurui; Sun, Mengtao

    2014-06-24

    Plasmon-driven sequential chemical reactions were successfully realized in an aqueous environment. In an electrochemical environment, sequential chemical reactions were driven by an applied potential and laser irradiation. Furthermore, the rate of the chemical reaction was controlled via pH, which provides indirect evidence that the hot electrons generated from plasmon decay play an important role in plasmon-driven chemical reactions. In acidic conditions, the hot electrons were captured by the abundant H(+) in the aqueous environment, which prevented the chemical reaction. The developed plasmon-driven chemical reactions in an aqueous environment will significantly expand the applications of plasmon chemistry and may provide a promising avenue for green chemistry using plasmon catalysis in aqueous environments under irradiation by sunlight.

  8. Better together: reduced compliance after sequential versus simultaneous bilateral hearing aids fitting.

    Science.gov (United States)

    Lavie, Limor; Banai, Karen; Attias, Joseph; Karni, Avi

    2014-03-01

    The purpose of this study was to determine the effects of sequential versus simultaneous bilateral hearing aids fitting on patient compliance. Thirty-six older adults with hearing impairment participated in this study. Twelve were fitted with bilateral hearing aids simultaneously. The remaining participants were fitted sequentially: One hearing aid (to the left or to the right ear) was used initially; 1 month later, the other ear was also fitted with a hearing aid for bilateral use. Self-reports on usefulness and compliance were elicited after the first and second months of hearing aid use. In addition, the number of hours the hearing aids were used was extracted from the data loggings of each device. Simultaneous fitting resulted in high levels of compliance and consistent usage throughout the study period. Sequential fitting resulted in abrupt reduction in compliance and hours of use once the second hearing aid was added, both in the clinical scoring and in the data loggings. Simultaneous fitting of bilateral hearing aids results in better compliance compared with sequential fitting. The addition of a second hearing aid after a relatively short period of monaural use may lead to inconsistent use of both hearing aids.

  9. Adjuvant sequential chemo and radiotherapy improves the oncological outcome in high risk endometrial cancer

    Science.gov (United States)

    Signorelli, Mauro; Lissoni, Andrea Alberto; De Ponti, Elena; Grassi, Tommaso; Ponti, Serena

    2015-01-01

    Objective Evaluation of the impact of sequential chemoradiotherapy in high risk endometrial cancer (EC). Methods Two hundred fifty-four women with stage IB grade 3, II and III EC (2009 FIGO staging), were included in this retrospective study. Results Stage I, II, and III was 24%, 28.7%, and 47.3%, respectively. Grade 3 tumor was 53.2% and 71.3% had deep myometrial invasion. One hundred sixty-five women (65%) underwent pelvic (+/- aortic) lymphadenectomy and 58 (22.8%) had nodal metastases. Ninety-eight women (38.6%) underwent radiotherapy, 59 (23.2%) chemotherapy, 42 (16.5%) sequential chemoradiotherapy, and 55 (21.7%) were only observed. After a median follow-up of 101 months, 78 women (30.7%) relapsed and 91 women (35.8%) died. Sequential chemoradiotherapy improved survival rates in women who did not undergo nodal evaluation (disease-free survival [DFS], p=0.040; overall survival [OS], p=0.024) or pelvic (+/- aortic) lymphadenectomy (DFS, p=0.008; OS, p=0.021). Sequential chemoradiotherapy improved both DFS (p=0.015) and OS (p=0.014) in stage III, while only a trend was found for DFS (p=0.210) and OS (p=0.102) in stage I-II EC. In the multivariate analysis, only age (≤65 years) and sequential chemoradiotherapy were statistically related to the prognosis. Conclusion Sequential chemoradiotherapy improves survival rates in high risk EC compared with chemotherapy or radiotherapy alone, in particular in stage III. PMID:26197768

  10. Eyewitness decisions in simultaneous and sequential lineups: a dual-process signal detection theory analysis.

    Science.gov (United States)

    Meissner, Christian A; Tredoux, Colin G; Parker, Janat F; MacLin, Otto H

    2005-07-01

    Many eyewitness researchers have argued for the application of a sequential alternative to the traditional simultaneous lineup, given its role in decreasing false identifications of innocent suspects (sequential superiority effect). However, Ebbesen and Flowe (2002) have recently noted that sequential lineups may merely bring about a shift in response criterion, having no effect on discrimination accuracy. We explored this claim, using a method that allows signal detection theory measures to be collected from eyewitnesses. In three experiments, lineup type was factorially combined with conditions expected to influence response criterion and/or discrimination accuracy. Results were consistent with signal detection theory predictions, including that of a conservative criterion shift with the sequential presentation of lineups. In a fourth experiment, we explored the phenomenological basis for the criterion shift, using the remember-know-guess procedure. In accord with previous research, the criterion shift in sequential lineups was associated with a reduction in familiarity-based responding. It is proposed that the relative similarity between lineup members may create a context in which fluency-based processing is facilitated to a greater extent when lineup members are presented simultaneously.

  11. Sequential and Simultaneous Processing Abilities of High-Functioning Autistic and Language-Impaired Children.

    Science.gov (United States)

    Allen, Mark H.; And Others

    1991-01-01

    This study found that a group of 20 children (ages 6-12) with autism and a group of 20 children with developmental receptive language disorder both manifested a relative sequential processing deficit. The groups did not differ significantly on overall sequential and simultaneous processing capabilities relative to their degree of language…

  12. Sequential boundaries approach in clinical trials with unequal allocation ratios

    Directory of Open Access Journals (Sweden)

    Ayatollahi Seyyed

    2006-01-01

    Full Text Available Abstract Background In clinical trials, both unequal randomization design and sequential analyses have ethical and economic advantages. In the single-stage-design (SSD, however, if the sample size is not adjusted based on unequal randomization, the power of the trial will decrease, whereas with sequential analysis the power will always remain constant. Our aim was to compare sequential boundaries approach with the SSD when the allocation ratio (R was not equal. Methods We evaluated the influence of R, the ratio of the patients in experimental group to the standard group, on the statistical properties of two-sided tests, including the two-sided single triangular test (TT, double triangular test (DTT and SSD by multiple simulations. The average sample size numbers (ASNs and power (1-β were evaluated for all tests. Results Our simulation study showed that choosing R = 2 instead of R = 1 increases the sample size of SSD by 12% and the ASN of the TT and DTT by the same proportion. Moreover, when R = 2, compared to the adjusted SSD, using the TT or DTT allows to retrieve the well known reductions of ASN observed when R = 1, compared to SSD. In addition, when R = 2, compared to SSD, using the TT and DTT allows to obtain smaller reductions of ASN than when R = 1, but maintains the power of the test to its planned value. Conclusion This study indicates that when the allocation ratio is not equal among the treatment groups, sequential analysis could indeed serve as a compromise between ethicists, economists and statisticians.

  13. Accurately controlled sequential self-folding structures by polystyrene film

    Science.gov (United States)

    Deng, Dongping; Yang, Yang; Chen, Yong; Lan, Xing; Tice, Jesse

    2017-08-01

    Four-dimensional (4D) printing overcomes the traditional fabrication limitations by designing heterogeneous materials to enable the printed structures evolve over time (the fourth dimension) under external stimuli. Here, we present a simple 4D printing of self-folding structures that can be sequentially and accurately folded. When heated above their glass transition temperature pre-strained polystyrene films shrink along the XY plane. In our process silver ink traces printed on the film are used to provide heat stimuli by conducting current to trigger the self-folding behavior. The parameters affecting the folding process are studied and discussed. Sequential folding and accurately controlled folding angles are achieved by using printed ink traces and angle lock design. Theoretical analyses are done to guide the design of the folding processes. Programmable structures such as a lock and a three-dimensional antenna are achieved to test the feasibility and potential applications of this method. These self-folding structures change their shapes after fabrication under controlled stimuli (electric current) and have potential applications in the fields of electronics, consumer devices, and robotics. Our design and fabrication method provides an easy way by using silver ink printed on polystyrene films to 4D print self-folding structures for electrically induced sequential folding with angular control.

  14. Loss-pattern identification in near-real-time accounting systems

    International Nuclear Information System (INIS)

    Argentesi, F.; Hafer, J.F.; Markin, J.T.; Shipley, J.P.

    1982-01-01

    To maximize the benefits from an advanced safeguards technique such as near-real-time accounting (NRTA), sophisticated methods of analyzing sequential materials accounting data are necessary. The methods must be capable of controlling the overall false-alarm rate while assuring good power of detection against all possible diversion scenarios. A method drawn from the field of pattern recognition and related to the alarm-sequence chart appears to be promising. Power curves based on Monte Carlo calculations illustrate the improvements over more conventional methods. 3 figures, 2 tables

  15. Sequential capillary electrophoresis analysis using optically gated sample injection and UV/vis detection.

    Science.gov (United States)

    Liu, Xiaoxia; Tian, Miaomiao; Camara, Mohamed Amara; Guo, Liping; Yang, Li

    2015-10-01

    We present sequential CE analysis of amino acids and L-asparaginase-catalyzed enzyme reaction, by combing the on-line derivatization, optically gated (OG) injection and commercial-available UV-Vis detection. Various experimental conditions for sequential OG-UV/vis CE analysis were investigated and optimized by analyzing a standard mixture of amino acids. High reproducibility of the sequential CE analysis was demonstrated with RSD values (n = 20) of 2.23, 2.57, and 0.70% for peak heights, peak areas, and migration times, respectively, and the LOD of 5.0 μM (for asparagine) and 2.0 μM (for aspartic acid) were obtained. With the application of the OG-UV/vis CE analysis, sequential online CE enzyme assay of L-asparaginase-catalyzed enzyme reaction was carried out by automatically and continuously monitoring the substrate consumption and the product formation every 12 s from the beginning to the end of the reaction. The Michaelis constants for the reaction were obtained and were found to be in good agreement with the results of traditional off-line enzyme assays. The study demonstrated the feasibility and reliability of integrating the OG injection with UV/vis detection for sequential online CE analysis, which could be of potential value for online monitoring various chemical reaction and bioprocesses. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Simultaneous Versus Sequential Side-by-Side Bilateral Metal Stent Placement for Malignant Hilar Biliary Obstructions.

    Science.gov (United States)

    Inoue, Tadahisa; Ishii, Norimitsu; Kobayashi, Yuji; Kitano, Rena; Sakamoto, Kazumasa; Ohashi, Tomohiko; Nakade, Yukiomi; Sumida, Yoshio; Ito, Kiyoaki; Nakao, Haruhisa; Yoneda, Masashi

    2017-09-01

    Endoscopic bilateral self-expandable metallic stent (SEMS) placement for malignant hilar biliary obstructions (MHBOs) is technically demanding, and a second SEMS insertion is particularly challenging. A simultaneous side-by-side (SBS) placement technique using a thinner delivery system may mitigate these issues. We aimed to examine the feasibility and efficacy of simultaneous SBS SEMS placement for treating MHBOs using a novel SEMS that has a 5.7-Fr ultra-thin delivery system. Thirty-four patients with MHBOs underwent SBS SEMS placement between 2010 and 2016. We divided the patient cohort into those who underwent sequential (conventional) SBS placement between 2010 and 2014 (sequential group) and those who underwent simultaneous SBS placement between 2015 and 2016 (simultaneous group), and compared the groups with respect to the clinical outcomes. The technical success rates were 71% (12/17) and 100% (17/17) in the sequential and simultaneous groups, respectively, a difference that was significant (P = .045). The median procedure time was significantly shorter in the simultaneous group (22 min) than in the sequential group (52 min) (P = .017). There were no significant group differences in the time to recurrent biliary obstruction (sequential group: 113 days; simultaneous group: 140 days) or other adverse event rates (sequential group: 12%; simultaneous group: 12%). Simultaneous SBS placement using the novel 5.7-Fr SEMS delivery system may be more straightforward and have a higher success rate compared to that with sequential SBS placement. This new method may be useful for bilateral stenting to treat MHBOs.

  17. Bidding in sequential electricity markets: The Nordic case

    DEFF Research Database (Denmark)

    Boomsma, Trine Krogh; Juul, Nina; Fleten, Stein-Erik

    2014-01-01

    problem as a multi-stage stochastic program. We investigate whether higher risk exposure can explain the hesitation, often observed in practice, to bid into the balancing market, even in cases of higher expected price levels. Furthermore, we quantify the gain from coordinated bidding, and by deriving......For electricity market participants trading in sequential markets with differences in price levels and risk exposure, coordinated bidding is highly relevant. We consider a Nordic power producer who engages in the day-ahead spot market and the near real-time balancing market. In both markets......, clearing prices and dispatched volumes are unknown at the time of bidding. However, in the balancing market, the agent faces an additional risk of not being dispatched. Taking into account the sequential clearing of these markets and the gradual realization of market prices, we formulate the bidding...

  18. Sequential and double sequential fission observed in heavy ion interaction of (11.67 MeV/u)197Au projectile with 197Au target

    International Nuclear Information System (INIS)

    Nasir, Tabassum; Khan, Ehsan Ullah; Baluch, Javaid Jahan; Shafi-Ur-Rehman; Matiullah; Rafique, Muhammad

    2009-01-01

    The heavy ion interaction of 11.67 MeV/u 197 Au+ 197 Au has been investigated using mica as a passive detector. By employing Solid State Nuclear Track Detection Technique the data of elastic scattering as well as inelastic reaction channel was collected. The off-line data analysis of multi-pronged events was performed by measuring the three-dimensional geometrical coordinates of correlated tracks on event-by-event basis. Multi pronged events observed in this reaction were due to sequential and double sequential fission. Using a computer code PRONGY based on the procedure of internal calibration, it was possible to derive quantities like mass transfer, total kinetic energy loss and scattering angles. (author)

  19. General Atomic HTGR fuel reprocessing pilot plant: results of initial sequential equipment operation

    International Nuclear Information System (INIS)

    1978-09-01

    In September 1977, the processing of 20 large high-temperature gas-cooled reactor (LHTGR) fuel elements was completed sequentially through the head-end cold pilot plant equipment. This report gives a brief description of the equipment and summarizes the results of the sequential operation of the pilot plant. 32 figures, 15 tables

  20. Bootstrap Sequential Determination of the Co-integration Rank in VAR Models

    DEFF Research Database (Denmark)

    Guiseppe, Cavaliere; Rahbæk, Anders; Taylor, A.M. Robert

    with empirical rejection frequencies often very much in excess of the nominal level. As a consequence, bootstrap versions of these tests have been developed. To be useful, however, sequential procedures for determining the co-integrating rank based on these bootstrap tests need to be consistent, in the sense...... in the literature by proposing a bootstrap sequential algorithm which we demonstrate delivers consistent cointegration rank estimation for general I(1) processes. Finite sample Monte Carlo simulations show the proposed procedure performs well in practice....

  1. Radiobiological studies of cells in multicellular spheroids using a sequential trypsinization technique

    International Nuclear Information System (INIS)

    Giesbrecht, J.L.; Wilson, W.R.; Hill, R.P.

    1981-01-01

    The radiation response of V79 Chinese hamster cells grown as multicellular spheroids has been investigated by determining survival curves for treatment under a variety of different oxygen concentrations. Spheroids were irradiated under fully oxygenated conditions in air-equilibrated medium at 37 0 C, in medium exposed to lower oxygen tension (5% O 2 ) for times varying from 1 hr to 3 days, or under anoxic conditions. For comparison with the spheroids, using identical treatment conditions, V79 cells were grown in suspension as a subconfluent monolayer attached to Sephadex (microcarrier) beads and irradiated under fully oxygenated or anoxic conditions. The radiation response of cells at different depths within the spheroid was investigated by using a sequential trypsinization technique developed to remove eight or nine shells of cells successively from the spheroid surface. When irradiation was given under fully oxygenated conditions the outer few cell layers were more sensitive than the inner cells, a finding which is not understood. As expected the inner cells in spheroids irradiated in air (at 37 0 C) or in 5% O 2 are more resistant than the outer cells. For an acute exposure to 5% O 2 (1 hr) in the inner cells displayed full radiobiological hypoxia; however, for chronic exposures to low oxygen this was not the case. These results with the sequential trypsinization procedure suggest that the radiation response of cells in spheroids is more complex than anticipted

  2. Comparison of human embryomorphokinetic parameters in sequential or global culture media.

    Science.gov (United States)

    Kazdar, Nadia; Brugnon, Florence; Bouche, Cyril; Jouve, Guilhem; Veau, Ségolène; Drapier, Hortense; Rousseau, Chloé; Pimentel, Céline; Viard, Patricia; Belaud-Rotureau, Marc-Antoine; Ravel, Célia

    2017-08-01

    A prospective study on randomized patients was conducted to determine how morphokinetic parameters are altered in embryos grown in sequential versus global culture media. Eleven morphokinetic parameters of 160 single embryos transferred were analyzed by time lapse imaging involving two University-affiliated in vitro fertilization (IVF) centers. We found that the fading of the two pronuclei occurred earlier in global (22.56±2.15 hpi) versus sequential media (23.63±2.71 hpi; p=0.0297). Likewise, the first cleavage started earlier at 24.52±2.33 hpi vs 25.76±2.95 hpi (p=0.0158). Also, the first cytokinesis was shorter in global medium, lasting 18±10.2 minutes in global versus 36±37.8 minutes in sequential culture medium (p culture medium. Our study highlights the need to adapt morphokinetic analysis accordingly to the type of media used to best support human early embryo development.

  3. Probing finite coarse-grained virtual Feynman histories with sequential weak values

    Science.gov (United States)

    Georgiev, Danko; Cohen, Eliahu

    2018-05-01

    Feynman's sum-over-histories formulation of quantum mechanics has been considered a useful calculational tool in which virtual Feynman histories entering into a coherent quantum superposition cannot be individually measured. Here we show that sequential weak values, inferred by consecutive weak measurements of projectors, allow direct experimental probing of individual virtual Feynman histories, thereby revealing the exact nature of quantum interference of coherently superposed histories. Because the total sum of sequential weak values of multitime projection operators for a complete set of orthogonal quantum histories is unity, complete sets of weak values could be interpreted in agreement with the standard quantum mechanical picture. We also elucidate the relationship between sequential weak values of quantum histories with different coarse graining in time and establish the incompatibility of weak values for nonorthogonal quantum histories in history Hilbert space. Bridging theory and experiment, the presented results may enhance our understanding of both weak values and quantum histories.

  4. Physics-based, Bayesian sequential detection method and system for radioactive contraband

    Science.gov (United States)

    Candy, James V; Axelrod, Michael C; Breitfeller, Eric F; Chambers, David H; Guidry, Brian L; Manatt, Douglas R; Meyer, Alan W; Sale, Kenneth E

    2014-03-18

    A distributed sequential method and system for detecting and identifying radioactive contraband from highly uncertain (noisy) low-count, radionuclide measurements, i.e. an event mode sequence (EMS), using a statistical approach based on Bayesian inference and physics-model-based signal processing based on the representation of a radionuclide as a monoenergetic decomposition of monoenergetic sources. For a given photon event of the EMS, the appropriate monoenergy processing channel is determined using a confidence interval condition-based discriminator for the energy amplitude and interarrival time and parameter estimates are used to update a measured probability density function estimate for a target radionuclide. A sequential likelihood ratio test is then used to determine one of two threshold conditions signifying that the EMS is either identified as the target radionuclide or not, and if not, then repeating the process for the next sequential photon event of the EMS until one of the two threshold conditions is satisfied.

  5. Catalysis of Silver catfish Major Hepatic Glutathione Transferase proceeds via rapid equilibrium sequential random Mechanism

    Directory of Open Access Journals (Sweden)

    Ayodele O. Kolawole

    Full Text Available Fish hepatic glutathione transferases are connected with the elimination of intracellular pollutants and detoxification of organic micro-pollutants in their aquatic ecosystem. The two-substrate steady state kinetic mechanism of Silver catfish (Synodontis eupterus major hepatic glutathione transferases purified to apparent homogeneity was explored. The enzyme was dimeric enzyme with a monomeric size of 25.6 kDa. Initial-velocity studies and Product inhibition patterns by methyl glutathione and chloride with respect to GSH-CDNB; GSH-ρ-nitrophenylacetate; and GSH-Ethacrynic acid all conforms to a rapid equilibrium sequential random Bi Bi kinetic mechanism rather than steady state sequential random Bi Bi kinetic. α was 2.96 ± 0.35 for the model. The pH profile of Vmax/KM (with saturating 1-chloro-2,4-dinitrobenzene and variable GSH concentrations showed apparent pKa value of 6.88 and 9.86. Inhibition studies as a function of inhibitor concentration show that the enzyme is a homodimer and near neutral GST. The enzyme poorly conjugates 4-hydroxylnonenal and cumene hydroperoxide and may not be involved in oxidative stress protection. The seGST is unique and overwhelmingly shows characteristics similar to those of homodimeric class Pi GSTs, as was indicated by its kinetic mechanism, substrate specificity and inhibition studies. The rate- limiting step, probably the product release, of the reaction is viscosity-dependent and is consequential if macro-viscosogen or micro-viscosogen. Keywords: Silver catfish, Glutathione transferase, Steady-state, Kinetic mechanism, Inhibition

  6. Simultaneous and sequential transfer of proton and alpha-particle in the elastic 11B+16O scattering

    International Nuclear Information System (INIS)

    Kamys, B.; Rudy, Z.; Kisiel, J.; Kwasniewicsz, E.; Wolter, H.H.

    1992-01-01

    We have developed a method to treat multi-nucleon transfer as the transfer of two - possible different - subclusters, as e.g. with ' 5 Li'=(α,p). As a consequence we take into account two reaction mechanisms, the one-step simultaneous and the two-step sequential transfer of the two clusters. We formulate the method of calculation of the simultaneous transfer form factor for two non-identifical particles and also of the two-cluster spectroscopic amplitudes from shell model wave functions. We apply the method to the elastic transfer reaction 11 B( 16 O, 11 B) 11 O together with the single α and p transfer reaction 11 B( 16 O, 15 N) 12 C for E lab between 30 and 60 MeV. We obtain a consistently good description of all the data by reasonable adjustment of the spectroscopic amplitudes. In particular we find that the simultaneous (αp) transfer is considerably more important than the sequential transfer indicating strong five-nucleon correlations in these light nuclei. (orig.)

  7. Sequential accelerated tests: Improving the correlation of accelerated tests to module performance in the field

    Science.gov (United States)

    Felder, Thomas; Gambogi, William; Stika, Katherine; Yu, Bao-Ling; Bradley, Alex; Hu, Hongjie; Garreau-Iles, Lucie; Trout, T. John

    2016-09-01

    DuPont has been working steadily to develop accelerated backsheet tests that correlate with solar panels observations in the field. This report updates efforts in sequential testing. Single exposure tests are more commonly used and can be completed more quickly, and certain tests provide helpful predictions of certain backsheet failure modes. DuPont recommendations for single exposure tests are based on 25-year exposure levels for UV and humidity/temperature, and form a good basis for sequential test development. We recommend a sequential exposure of damp heat followed by UV then repetitions of thermal cycling and UVA. This sequence preserves 25-year exposure levels for humidity/temperature and UV, and correlates well with a large body of field observations. Measurements can be taken at intervals in the test, although the full test runs 10 months. A second, shorter sequential test based on damp heat and thermal cycling tests mechanical durability and correlates with loss of mechanical properties seen in the field. Ongoing work is directed toward shorter sequential tests that preserve good correlation to field data.

  8. Patterning of anteroposterior body axis displayed in the expression of Hox genes in sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Kikuchi, Mani; Omori, Akihito; Kurokawa, Daisuke; Akasaka, Koji

    2015-09-01

    The presence of an anteroposterior body axis is a fundamental feature of bilateria. Within this group, echinoderms have secondarily evolved pentameral symmetric body plans. Although all echinoderms present bilaterally symmetric larval stages, they dramatically rearrange their body axis and develop a pentaradial body plan during metamorphosis. Therefore, the location of their anteroposterior body axis in adult forms remains a contentious issue. Unlike other echinoderms, sea cucumbers present an obvious anteroposterior axis not rearranged during metamorphosis, thus representing an interesting group to study their anteroposterior axis patterning. Hox genes are known to play a broadly conserved role in anteroposterior axis patterning in deuterostomes. Here, we report the expression patterns of Hox genes from early development to pentactula stage in sea cucumber. In early larval stages, five Hox genes (AjHox1, AjHox7, AjHox8, AjHox11/13a, and AjHox11/13b) were expressed sequentially along the archenteron, suggesting that the role of anteroposterior patterning of the Hox genes is conserved in bilateral larvae of echinoderms. In doliolaria and pentactula stages, eight Hox genes (AjHox1, AjHox5, AjHox7, AjHox8, AjHox9/10, AjHox11/13a, AjHox11/13b, and AjHox11/13c) were expressed sequentially along the digestive tract, following a similar expression pattern to that found in the visceral mesoderm of other bilateria. Unlike other echinoderms, pentameral expression patterns of AjHox genes were not observed in sea cucumber. Altogether, we concluded that AjHox genes are involved in the patterning of the digestive tract in both larvae and metamorphosis of sea cucumbers. In addition, the anteroposterior axis in sea cucumbers might be patterned like that of other bilateria.

  9. An automatic system for acidity determination based on sequential injection titration and the monosegmented flow approach.

    Science.gov (United States)

    Kozak, Joanna; Wójtowicz, Marzena; Gawenda, Nadzieja; Kościelniak, Paweł

    2011-06-15

    An automatic sequential injection system, combining monosegmented flow analysis, sequential injection analysis and sequential injection titration is proposed for acidity determination. The system enables controllable sample dilution and generation of standards of required concentration in a monosegmented sequential injection manner, sequential injection titration of the prepared solutions, data collecting, and handling. It has been tested on spectrophotometric determination of acetic, citric and phosphoric acids with sodium hydroxide used as a titrant and phenolphthalein or thymolphthalein (in the case of phosphoric acid determination) as indicators. Accuracy better than |4.4|% (RE) and repeatability better than 2.9% (RSD) have been obtained. It has been applied to the determination of total acidity in vinegars and various soft drinks. The system provides low sample (less than 0.3 mL) consumption. On average, analysis of a sample takes several minutes. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Phylogenetic patterns and phenotypic plasticity of molluscan sexual systems.

    Science.gov (United States)

    Collin, Rachel

    2013-10-01

    Molluscs show a wide diversity of sexual systems and strategies. There are both gastropod and bivalve families that are each primarily dioecious, simultaneous hermaphrodites, or sequential hermaphrodites, and other families in which almost every sexual strategy occurs. The multiple evolutionary transitions of sexual systems within molluscs would allow comparative analyses of the associated ecological factors, but data on all but a few groups are too sparse to draw many solid conclusions. The phylogenetic distribution of sexual systems in the Mollusca shows that gastropods and bivalves demonstrate different patterns, possibly associated with the presence/absence of copulation. The distribution of change of sex suggests that, in gastropods, sequential hermaphrodites do not evolve from simultaneous hermaphrodites, and that sex reversal (flip-flopping) occurs in free-spawners but not in copulators. Three well-studied protandrous gastropod groups (calyptraeids, coralliophilids, and patellogastropods) show similar responses to environmental conditions and associations with conspecifics. They all have the following attributes: (1) they are sedentary, (2) they live in groups, patches, or aggregates, and (3) size at sex change varies among sites and among aggregates. In addition the available experimental evidence suggests that (4) the presence of females or large individuals represses growth and sex change of males, and (5) behavior seems to mediate the repressive influence of large females. Available data from other species tend to support these patterns. Finally, the repression of growth of males by females in protandry likely facilitates the evolution of dwarf males.

  11. Imaging CT findings in cases of subdural hematoma after cardiovascular surgery. Initial signs of SDH

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Michiyuki; Kuriyama, Yoshihiro; Sawada, Tohru; Ogawa, Makoto; Kaneko, Takaji; Sakamoto, Akira; Kawazoe, Kouhei; Fujita, Tsuyoshi; Omae, Teruo

    1987-12-01

    A characteristic initial sign of CT findings, as seen in cases of subdural hematoma (SDH) after cardiovascular surgery, was reported. Central-nervous-system (CNS) complications after cardiovascular surgery have been thought to be due mainly to the ischemic brain damage caused by both reduced cerebral perfusion pressure and microembolism during extracorporeal circulation. However, we observed 8 cases of SDH in 39 patients suffering from major CNS complications after cardiovascular surgery. In view of these experiences, SDH was thought to be one of the most significant factors causing CNS complications after cardiovascular surgery. In the sequential CT scans of 8 cases of SDH, four exhibited a typical, small, spotty high-density area in the early period of SDH. The clinical courses of these four patients were relatively acute or subacute, and the initial small high-density area progressed to definite SDH findings in that region in the follow-up CT. These initial findings of CT scans were regarded as ''initial signs of SDH-ISS-''. Although there have been many reports concerning the sequential CT changes in SDH, there has been no report describing the above-mentioned finding. It was emphasized that ''ISS'' is of great importance in the early management for SDH.

  12. Effect of cryoablation sequential chemotherapy on patients with advanced non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Shu-Hui Yao

    2016-03-01

    Full Text Available Objective: To evaluate the effect of cryoablation sequential chemotherapy on patients with advanced non-small cell lung cancer. Methods: A total of 39 cases with advanced non-small cell lung cancer who received cryoablation sequential chemotherapy and 39 cases with advanced non-small cell lung cancer who received chemotherapy alone were selected and enrolled in sequential group and control group, disease progression and survival of two groups were followed up, and contents of tumor markers and angiogenesis molecules in serum as well as contents of T-lymphocyte subsets in peripheral blood were detected. Results: Progressionfree survival and median overall survival (mOS of sequential group were longer than those of control group, and cumulative cases of tumor progression at various points in time were significantly less than those of control group (P<0.05; 1 month after treatment, serum tumor markers CEA, CYFRA21-1 and NSE contents, serum angiogenesis molecules PCDGF, VEGF and HDGF contents as well as CD3+CD4-CD8+CD28-T cell content in peripheral blood of sequential group were significantly lower than those of control group (P<0.05, and contents of CD3+CD4+CD8-T cell and CD3+CD4-CD8+CD28+T cell in peripheral blood were higher than those of control group (P<0.05. Conclusions: Cryoablation sequential chemotherapy can improve the prognosis of patients with advanced non-small cell lung cancer, delay disease progression, prolong survival time, inhibit angiogenesis and improve immune function.

  13. Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems.

    Science.gov (United States)

    Harari, Colin M; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T; Lubner, Meghan G; Hinshaw, J Louis; Ziemlewicz, Timothy; Brace, Christopher L

    2016-01-01

    To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015.

  14. Programme for test generation for combinatorial and sequential systems

    International Nuclear Information System (INIS)

    Tran Huy Hoan

    1973-01-01

    This research thesis reports the computer-assisted search for tests aimed at failure detection in combinatorial and sequential logic circuits. As he wants to deal with complex circuits with many modules such as those met in large scale integrated circuits (LSI), the author used propagation paths. He reports the development of a method which is valid for combinatorial systems and for several sequential circuits comprising elementary logic modules and JK and RS flip-flops. This method is developed on an IBM 360/91 computer in PL/1 language. The used memory space is limited and adjustable with respect to circuit dimension. Computing time is short when compared to that needed by other programmes. The solution is practical and efficient for failure test and localisation

  15. Sequential changes from minimal pancreatic inflammation to advanced alcoholic pancreatitis.

    Science.gov (United States)

    Noronha, M; Dreiling, D A; Bordalo, O

    1983-11-01

    A correlation of several clinical parameters and pancreatitis morphological alterations observed in chronic alcoholics with and without pancreatic is presented. Three groups of patients were studied: asymptomatic chronic alcoholics (24); non-alcoholic controls (10); and cases with advanced chronic pancreatitis (6). Clinical, biochemical and functional studies were performed. Morphological studies were made on surgical biopsy specimens in light and electron microscopy. The results of this study showed: 1) fat accumulates within pancreatic acinar cells in alcoholics drinking more than 80 g of ethanol per day; 2) ultrastructural changes found in acinar cells of the alcoholics are similar to those described for liver cells; 3) the alterations found in alcoholics without pancreatitis are also observed in those with advanced chronic pancreatitis. An attempt to correlate the sequential changes in the histopathology of alcoholic pancreatic disease with the clinical picture and secretory patterns was made. According to these observations, admitting the ultrastructural similarities between the liver and the pancreas and the recently demonstrated abnormalities of lipid metabolism in pancreatic cells in experimental animal research, the authors postulate a toxic-metabolic mechanism as a likely hypothesis for the pathogenesis of chronic alcoholic inflammation of the pancreas.

  16. Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation

    Directory of Open Access Journals (Sweden)

    Geerte G. J. Ramakers

    2017-11-01

    Full Text Available ImportanceThere is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus.ObjectiveTo investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years.Study designThis study is a secondary analysis as part of a multicenter randomized controlled trial.MethodsThirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI and Tinnitus Questionnaire (TQ.ResultsThe prevalence of preoperative tinnitus was 42% (16/38. One year after bilateral implantation, there was a median difference of −8 (inter-quartile range (IQR: −28 to 4 in THI score and −9 (IQR: −17 to −9 in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group

  17. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin

    2010-01-01

    Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...

  18. In Vivo Evaluation of Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Hansen, Peter Møller; Lange, Theis

    2012-01-01

    Ultrasound in vivo imaging using synthetic aperture sequential beamformation (SASB) is compared with conventional imaging in a double blinded study using side-by-side comparisons. The objective is to evaluate if the image quality in terms of penetration depth, spatial resolution, contrast...

  19. Sequential kidney scintiscanning before and after vascular reconstruction

    International Nuclear Information System (INIS)

    Siems, H.H.; Allenberg, J.R.; Hupp, T.; Clorius, J.H.

    1985-01-01

    In this follow-up study sequential scintigraphy was performed on 20 of selected patients up to 3.4 years after operation, the results are compared with the pre-operative examinations and with the surgical effect on the increased blood pressure. (orig./MG) [de

  20. Exogenous lipoid pneumonia: high-resolution CT findings

    International Nuclear Information System (INIS)

    Lee, J.S.; Song, K.S.; Lim, T.H.; Im, J.G.; Seo, J.B.

    1999-01-01

    The aim of this study was to assess high-resolution computed tomography (HRCT) findings of exogenous lipoid pneumonia. High-resolution computed tomography was obtained in 25 patients with proven exogenous lipoid pneumonia resulting from aspiration of squalene (derived from shark liver oil). Diagnosis was based on biopsy (n = 9), bronchoalveolar lavage (n = 8), or sputum cytology and clinical findings (n = 8). The clinical history of taking squalene was confirmed in all patients. The CT findings were classified into three patterns: diffuse ground-glass opacity, consolidation, and interstitial abnormalities. Distribution of the abnormalities, duration of taking squalene, predisposing factors for aspiration, and route of administration were analyzed. Ten patients showed diffuse ground-glass opacity pattern. Seven of 10 patients had predisposing conditions such as unconsciousness, pharyngeal dysmotility, or motor disturbances, and 6 patients had a recent history of taking large amount of squalene through nasal route. Seven patients who had consolidation pattern had a history of taking squalene for several months and did not have any predisposing factor. All of the 5 patients who had a pattern of interstitial abnormalities had a history of taking squalene longer than 1 year and showed segmental distribution of interstitial thickening with interposing ground-glass opacities. Three patients simultaneously had two different patterns at different lobes of the lung. The HRCT findings of lipoid pneumonia are ground-glass opacities, consolidation, and interstitial abnormalities. These HRCT findings with appropriate inquiries could be useful for diagnosis of exogeneous lipoid pneumonia. (orig.)

  1. Sequential and parallel image restoration: neural network implementations.

    Science.gov (United States)

    Figueiredo, M T; Leitao, J N

    1994-01-01

    Sequential and parallel image restoration algorithms and their implementations on neural networks are proposed. For images degraded by linear blur and contaminated by additive white Gaussian noise, maximum a posteriori (MAP) estimation and regularization theory lead to the same high dimension convex optimization problem. The commonly adopted strategy (in using neural networks for image restoration) is to map the objective function of the optimization problem into the energy of a predefined network, taking advantage of its energy minimization properties. Departing from this approach, we propose neural implementations of iterative minimization algorithms which are first proved to converge. The developed schemes are based on modified Hopfield (1985) networks of graded elements, with both sequential and parallel updating schedules. An algorithm supported on a fully standard Hopfield network (binary elements and zero autoconnections) is also considered. Robustness with respect to finite numerical precision is studied, and examples with real images are presented.

  2. Competence and Praxis: Sequential Analysis in German Sociology

    Directory of Open Access Journals (Sweden)

    Kai-Olaf Maiwald

    2005-09-01

    Full Text Available In German social research nowadays most qualitative methodologies employ sequential analysis. This article explores the similarities and differences in conceptualising and practising this method. First, the working consensus, conceived as a shared set of methodological assumptions, is explicated. Second, with regard to three major paradigms of qualitative research in Germany—conversation analysis, objective hermeneutics, and hermeneutic sociology of knowledge—the dif­ferent ways of doing sequential analysis are investigated to locate the points of departure from a working consensus. It is argued that differences arise from different case-perspectives and, relative to that, from different modes of introducing general knowl­edge, i.e. knowledge that is not specific for the analysed case, into the interpretation. An import­ant notion to emerge from the comparison is the distinction between competence and praxis. URN: urn:nbn:de:0114-fqs0503310

  3. Simultaneous sequential monitoring of efficacy and safety led to masking of effects.

    Science.gov (United States)

    van Eekelen, Rik; de Hoop, Esther; van der Tweel, Ingeborg

    2016-08-01

    Usually, sequential designs for clinical trials are applied on the primary (=efficacy) outcome. In practice, other outcomes (e.g., safety) will also be monitored and influence the decision whether to stop a trial early. Implications of simultaneous monitoring on trial decision making are yet unclear. This study examines what happens to the type I error, power, and required sample sizes when one efficacy outcome and one correlated safety outcome are monitored simultaneously using sequential designs. We conducted a simulation study in the framework of a two-arm parallel clinical trial. Interim analyses on two outcomes were performed independently and simultaneously on the same data sets using four sequential monitoring designs, including O'Brien-Fleming and Triangular Test boundaries. Simulations differed in values for correlations and true effect sizes. When an effect was present in both outcomes, competition was introduced, which decreased power (e.g., from 80% to 60%). Futility boundaries for the efficacy outcome reduced overall type I errors as well as power for the safety outcome. Monitoring two correlated outcomes, given that both are essential for early trial termination, leads to masking of true effects. Careful consideration of scenarios must be taken into account when designing sequential trials. Simulation results can help guide trial design. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. The statistical decay of very hot nuclei: from sequential decay to multifragmentation

    International Nuclear Information System (INIS)

    Carlson, B.V.; Donangelo, R.; Universidad de la Republica, Montevideo; Souza, S.R.; Universidade Federal do Rio Grande do Sul; Lynch, W.G.; Steiner, A.W.; Tsang, M.B.

    2010-01-01

    Full text. At low excitation energies, the compound nucleus typically decays through the sequential emission of light particles. As the energy increases, the emission probability of heavier fragments increases until, at sufficiently high energies, several heavy complex fragments are emitted during the decay. The extent to which this fragment emission is simultaneous or sequential has been a subject of theoretical and experimental study for almost 30 years. The Statistical Multifragmentation Model, an equilibrium model of simultaneous fragment emission, uses the configurations of a statistical ensemble to determine the distribution of primary fragments of a compound nucleus. The primary fragments are then assumed to decay by sequential compound emission or Fermi breakup. As the first step toward a more unified model of these processes, we demonstrate the equivalence of a generalized Fermi breakup model, in which densities of excited states are taken into account, to the microcanonical version of the statistical multifragmentation model. We then establish a link between this unified Fermi breakup / statistical multifragmentation model and the well-known process of compound nucleus emission, which permits to consider simultaneous and sequential emission on the same footing. Within this unified framework, we analyze the increasing importance of simultaneous, multifragment decay with increasing excitation energy and decreasing lifetime of the compound nucleus. (author)

  5. A Bayesian sequential design with adaptive randomization for 2-sided hypothesis test.

    Science.gov (United States)

    Yu, Qingzhao; Zhu, Lin; Zhu, Han

    2017-11-01

    Bayesian sequential and adaptive randomization designs are gaining popularity in clinical trials thanks to their potentials to reduce the number of required participants and save resources. We propose a Bayesian sequential design with adaptive randomization rates so as to more efficiently attribute newly recruited patients to different treatment arms. In this paper, we consider 2-arm clinical trials. Patients are allocated to the 2 arms with a randomization rate to achieve minimum variance for the test statistic. Algorithms are presented to calculate the optimal randomization rate, critical values, and power for the proposed design. Sensitivity analysis is implemented to check the influence on design by changing the prior distributions. Simulation studies are applied to compare the proposed method and traditional methods in terms of power and actual sample sizes. Simulations show that, when total sample size is fixed, the proposed design can obtain greater power and/or cost smaller actual sample size than the traditional Bayesian sequential design. Finally, we apply the proposed method to a real data set and compare the results with the Bayesian sequential design without adaptive randomization in terms of sample sizes. The proposed method can further reduce required sample size. Copyright © 2017 John Wiley & Sons, Ltd.

  6. A Cross-Validation Study of Sequential-Simultaneous Processing at Ages 2 1/2-12 1/2 Using the Kaufman Assessment Battery for Children (K-ABC).

    Science.gov (United States)

    Kamphaus, Randy W.; And Others

    The development of two types of mental processing (sequential and simultaneous) in preschool and elementary children was examined in this study. Specifically, the aims of the study were to develop a revised set of tasks based upon previous findings (Naglieri, Kaufman, Kaufman, & Kamphaus, 1981; Kaufman, Kaufman, Kamphaus, & Naglieri, in…

  7. A comprehensive analysis on preservation patterns of gene co-expression networks during Alzheimer's disease progression.

    Science.gov (United States)

    Ray, Sumanta; Hossain, Sk Md Mosaddek; Khatun, Lutfunnesa; Mukhopadhyay, Anirban

    2017-12-20

    Alzheimer's disease (AD) is a chronic neuro-degenerative disruption of the brain which involves in large scale transcriptomic variation. The disease does not impact every regions of the brain at the same time, instead it progresses slowly involving somewhat sequential interaction with different regions. Analysis of the expression patterns of the genes in different regions of the brain influenced in AD surely contribute for a enhanced comprehension of AD pathogenesis and shed light on the early characterization of the disease. Here, we have proposed a framework to identify perturbation and preservation characteristics of gene expression patterns across six distinct regions of the brain ("EC", "HIP", "PC", "MTG", "SFG", and "VCX") affected in AD. Co-expression modules were discovered considering a couple of regions at once. These are then analyzed to know the preservation and perturbation characteristics. Different module preservation statistics and a rank aggregation mechanism have been adopted to detect the changes of expression patterns across brain regions. Gene ontology (GO) and pathway based analysis were also carried out to know the biological meaning of preserved and perturbed modules. In this article, we have extensively studied the preservation patterns of co-expressed modules in six distinct brain regions affected in AD. Some modules are emerged as the most preserved while some others are detected as perturbed between a pair of brain regions. Further investigation on the topological properties of preserved and non-preserved modules reveals a substantial association amongst "betweenness centrality" and "degree" of the involved genes. Our findings may render a deeper realization of the preservation characteristics of gene expression patterns in discrete brain regions affected by AD.

  8. A sequential mixed methods research approach to investigating HIV ...

    African Journals Online (AJOL)

    2016-09-03

    Sep 3, 2016 ... Sequential mixed methods research is an effective approach for ... show the effectiveness of the research method. ... qualitative data before quantitative datasets ..... whereby both types of data are collected simultaneously.

  9. Losing a dime with a satisfied mind: positive affect predicts less search in sequential decision making.

    Science.gov (United States)

    von Helversen, Bettina; Mata, Rui

    2012-12-01

    We investigated the contribution of cognitive ability and affect to age differences in sequential decision making by asking younger and older adults to shop for items in a computerized sequential decision-making task. Older adults performed poorly compared to younger adults partly due to searching too few options. An analysis of the decision process with a formal model suggested that older adults set lower thresholds for accepting an option than younger participants. Further analyses suggested that positive affect, but not fluid abilities, was related to search in the sequential decision task. A second study that manipulated affect in younger adults supported the causal role of affect: Increased positive affect lowered the initial threshold for accepting an attractive option. In sum, our results suggest that positive affect is a key factor determining search in sequential decision making. Consequently, increased positive affect in older age may contribute to poorer sequential decisions by leading to insufficient search. 2013 APA, all rights reserved

  10. Collaborative Filtering Based on Sequential Extraction of User-Item Clusters

    Science.gov (United States)

    Honda, Katsuhiro; Notsu, Akira; Ichihashi, Hidetomo

    Collaborative filtering is a computational realization of “word-of-mouth” in network community, in which the items prefered by “neighbors” are recommended. This paper proposes a new item-selection model for extracting user-item clusters from rectangular relation matrices, in which mutual relations between users and items are denoted in an alternative process of “liking or not”. A technique for sequential co-cluster extraction from rectangular relational data is given by combining the structural balancing-based user-item clustering method with sequential fuzzy cluster extraction appraoch. Then, the tecunique is applied to the collaborative filtering problem, in which some items may be shared by several user clusters.

  11. Sequential Uniformly Reweighted Sum-Product Algorithm for Cooperative Localization in Wireless Networks

    OpenAIRE

    Li, Wei; Yang, Zhen; Hu, Haifeng

    2014-01-01

    Graphical models have been widely applied in solving distributed inference problems in wireless networks. In this paper, we formulate the cooperative localization problem in a mobile network as an inference problem on a factor graph. Using a sequential schedule of message updates, a sequential uniformly reweighted sum-product algorithm (SURW-SPA) is developed for mobile localization problems. The proposed algorithm combines the distributed nature of belief propagation (BP) with the improved p...

  12. Pulmonary tuberculosis mimicking lung cancer on radiological findings: Evaluation of chest CT findings in pathologically proven 76 patients

    International Nuclear Information System (INIS)

    Lee, Daun; Shin, Sang Soo; Kim, Yun Hyeon; Kim, Hyoung Ook; Seon, Hyun Ju; Kang, Heoung Keun

    2012-01-01

    To evaluate chest CT features of pulmonary tuberculosis mimicking lung malignancy. We retrospectively reviewed chest CT findings for 76 consecutive patients (21-84 years, average: 63 years; M : F = 30 : 46) who underwent an invasive diagnostic procedure under the suspicion of lung cancer and were pathologically diagnosed as pulmonary tuberculosis by bronchoscopic biopsy (n = 49), transthoracic needle biopsy (n = 17), and surgical resection (n = 10). We categorized the chest CT patterns of those lesions as follows: bronchial narrowing or obstruction without a central mass like lesion (pattern 1), central mass-like lesion with distal atelectasis or obstructive pneumonia (pattern 2), peripheral nodule or mass including mass-like consolidation (pattern 3), and cavitary lesion (pattern 4). CT findings were reviewed with respect to the patterns and the locations of the lesions, parenchymal abnormalities adjacent to the lesions, the size, the border and pattern of enhancement for the peripheral nodule or mass and the thickness of the cavitary wall in the cavitary lesion. We also evaluated the abnormalities regarding the lymph node and pleura. Pattern 1 was the most common finding (n = 34), followed by pattern 3 (n = 23), pattern 2 (n = 11) and finally, pattern 4 (n = 8). The most frequently involving site in pattern 1 and 2 was the right middle lobe (n = 14/45). However, in pattern 3 and 4, the superior segment of right lower lobe (n = 5/31) was most frequently involved. Ill-defined small nodules and/or larger confluent nodules were found in the adjacent lung and at the other segment of the lung in 31 patients (40.8%). Enlarged lymph nodes were most commonly detected in the right paratracheal area (n = 9/18). Pleural effusion was demonstrated in 10 patients. On the CT, pulmonary tuberculosis mimicking lung cancer most commonly presented with bronchial narrowing or obstruction without a central mass-like lesion, which resulted in distal atelectasis and obstructive

  13. Pulmonary tuberculosis mimicking lung cancer on radiological findings: Evaluation of chest CT findings in pathologically proven 76 patients

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Daun; Shin, Sang Soo; Kim, Yun Hyeon [Chonnam National Univ. Hospital, Gwangju, (Korea, Republic of); Kim, Hyoung Ook; Seon, Hyun Ju; Kang, Heoung Keun [Chonnam National Univ. Hwasun Hospital, Hwasun (Korea, Republic of)

    2012-09-15

    To evaluate chest CT features of pulmonary tuberculosis mimicking lung malignancy. We retrospectively reviewed chest CT findings for 76 consecutive patients (21-84 years, average: 63 years; M : F = 30 : 46) who underwent an invasive diagnostic procedure under the suspicion of lung cancer and were pathologically diagnosed as pulmonary tuberculosis by bronchoscopic biopsy (n = 49), transthoracic needle biopsy (n = 17), and surgical resection (n = 10). We categorized the chest CT patterns of those lesions as follows: bronchial narrowing or obstruction without a central mass like lesion (pattern 1), central mass-like lesion with distal atelectasis or obstructive pneumonia (pattern 2), peripheral nodule or mass including mass-like consolidation (pattern 3), and cavitary lesion (pattern 4). CT findings were reviewed with respect to the patterns and the locations of the lesions, parenchymal abnormalities adjacent to the lesions, the size, the border and pattern of enhancement for the peripheral nodule or mass and the thickness of the cavitary wall in the cavitary lesion. We also evaluated the abnormalities regarding the lymph node and pleura. Pattern 1 was the most common finding (n = 34), followed by pattern 3 (n = 23), pattern 2 (n = 11) and finally, pattern 4 (n = 8). The most frequently involving site in pattern 1 and 2 was the right middle lobe (n = 14/45). However, in pattern 3 and 4, the superior segment of right lower lobe (n = 5/31) was most frequently involved. Ill-defined small nodules and/or larger confluent nodules were found in the adjacent lung and at the other segment of the lung in 31 patients (40.8%). Enlarged lymph nodes were most commonly detected in the right paratracheal area (n = 9/18). Pleural effusion was demonstrated in 10 patients. On the CT, pulmonary tuberculosis mimicking lung cancer most commonly presented with bronchial narrowing or obstruction without a central mass-like lesion, which resulted in distal atelectasis and obstructive

  14. Human visual system automatically represents large-scale sequential regularities.

    Science.gov (United States)

    Kimura, Motohiro; Widmann, Andreas; Schröger, Erich

    2010-03-04

    Our brain recordings reveal that large-scale sequential regularities defined across non-adjacent stimuli can be automatically represented in visual sensory memory. To show that, we adopted an auditory paradigm developed by Sussman, E., Ritter, W., and Vaughan, H. G. Jr. (1998). Predictability of stimulus deviance and the mismatch negativity. NeuroReport, 9, 4167-4170, Sussman, E., and Gumenyuk, V. (2005). Organization of sequential sounds in auditory memory. NeuroReport, 16, 1519-1523 to the visual domain by presenting task-irrelevant infrequent luminance-deviant stimuli (D, 20%) inserted among task-irrelevant frequent stimuli being of standard luminance (S, 80%) in randomized (randomized condition, SSSDSSSSSDSSSSD...) and fixed manners (fixed condition, SSSSDSSSSDSSSSD...). Comparing the visual mismatch negativity (visual MMN), an event-related brain potential (ERP) index of memory-mismatch processes in human visual sensory system, revealed that visual MMN elicited by deviant stimuli was reduced in the fixed compared to the randomized condition. Thus, the large-scale sequential regularity being present in the fixed condition (SSSSD) must have been represented in visual sensory memory. Interestingly, this effect did not occur in conditions with stimulus-onset asynchronies (SOAs) of 480 and 800 ms but was confined to the 160-ms SOA condition supporting the hypothesis that large-scale regularity extraction was based on perceptual grouping of the five successive stimuli defining the regularity. 2010 Elsevier B.V. All rights reserved.

  15. Application of full-face round by the sequential blasting machine in tunnel excavation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Y.D.; Park, B.K.; Lee, S.E.; Lim, H.U.

    1995-12-31

    Many methods and techniques have been developed to reduce ground vibrations. Some of them are an adoption of electric millisecond detonators with a sequential blasting machine and an improvement of initiating system with an adequate number of delay intervals. To reduce the level of ground vibration in tunnel excavation, the sequential blasting machine (S.B.M.) with decisecond detonators was adopted. A total of 134 blasts was recorded at various sites and the results were analyzed. The distances blast-to-structures were ranged from 20.3 to 42.0 meter, where charge weights were varied from 0.25 to 0.75kg per delay. It is proved that the sequential blasting in tunnel excavation is very effective to control ground vibration.

  16. Relations between the simultaneous and sequential transfer of two nucleons

    International Nuclear Information System (INIS)

    Satchler, G.R.

    1982-01-01

    The transfer of two nucleons between projectile and target in a direct or peripheral reaction such as (p,t) or ( 16 O, 14 C) may occur in one-step or two-steps. These we refer to as simultaneous and sequential transfers, respectively. In the former, the interaction acts once and both nucleons are transferred. In the latter, the interaction acts once to transfer one nucleon, the system then propagates in one or more intermediate states and is followed by a second action of the interaction to transfer the second nucleon. This process may be symbolized for the examples as (p,d; d,t) and ( 16 O, 15 N; 15 N, 14 C), implying the intermediate formation of a deuteron or the nucleus 15 N. In terms of a perturbation theory expansion, such as the distorted-wave Born series, simultaneous transfer is possible in first order while sequential transfer requires second order. The nuclear forces are predominantly two-body in character; hence, in first-order only one of the two nucleons experiences an interaction. The possibility of finding that the other nucleon has also transferred arises only because its state within the projectile is not orthogonal to the state in the target into which it transfers. In the two-step process each nucleon is transferred under the direct influence of an interaction with the target. The one-step and two-step amplitudes are frequently comparable in magnitude for light-ion reactions while the two-step may dominate in reactions with heavy ions. Our purpose here is to gain some insight into the relationship between the two amplitudes by using a simple approximate form of the theory. For simplicity, we shall discuss a light-ion reaction and, to be specific, we choose the (t,p) reaction (or the inverse (p,t) reaction)

  17. Sequential extraction applied to Peruibe black mud, SP, Brazil

    International Nuclear Information System (INIS)

    Torrecilha, Jefferson Koyaishi

    2014-01-01

    The Peruibe Black mud is used in therapeutic treatments such as psoriasis, peripheral dermatitis, acne and seborrhoea, as well as in the treatment of myalgia, arthritis, rheumatism and non-articular processes. Likewise other medicinal clays, it may not be free from possible adverse health effects due to possible hazardous minerals leading to respiratory system occurrences and other effects, caused by the presence of toxic elements. Once used for therapeutic purposes, any given material should be fully characterized and thus samples of Peruibe black mud were analyzed to determine physical and chemical properties: moisture content, organic matter and loss on ignition; pH, particle size, cation exchange capacity and swelling index. The elemental composition was determined by Neutron Activation Analysis, Atomic Absorption Graphite Furnace and X-ray fluorescence; the mineralogical composition was determined by X-ray diffraction. Another tool widely used to evaluate the behavior of trace elements, in various environmental matrices, is the sequential extraction. Thus, a sequential extraction procedure was applied to fractionate the mud in specific geochemical forms and verify how and how much of the elements may be contained in it. Considering the several sequential extraction procedures, BCR-701 method (Community Bureau of Reference) was used since it is considered the most reproducible among them. A simple extraction with an artificial sweat was, also, applied in order to verify which components are potentially available for absorption by the patient skin during the topical treatment. The results indicated that the mud is basically composed by a silty-clay material, rich in organic matter and with good cation exchange capacity. There were no significant variations in mineralogy and elemental composition of both, in natura and mature mud forms. The analysis by sequential extraction and by simple extraction indicated that the elements possibly available in larger

  18. Effects of simultaneous and optimized sequential cardiac resynchronization therapy on myocardial oxidative metabolism and efficiency.

    Science.gov (United States)

    Christenson, Stuart D; Chareonthaitawee, Panithaya; Burnes, John E; Hill, Michael R S; Kemp, Brad J; Khandheria, Bijoy K; Hayes, David L; Gibbons, Raymond J

    2008-02-01

    Cardiac resynchronization therapy (CRT) can improve left ventricular (LV) hemodynamics and function. Recent data suggest the energy cost of such improvement is favorable. The effects of sequential CRT on myocardial oxidative metabolism (MVO(2)) and efficiency have not been previously assessed. Eight patients with NYHA class III heart failure were studied 196 +/- 180 days after CRT implant. Dynamic [(11)C]acetate positron emission tomography (PET) and echocardiography were performed after 1 hour of: 1) AAI pacing, 2) simultaneous CRT, and 3) sequential CRT. MVO(2) was calculated using the monoexponential clearance rate of [(11)C]acetate (k(mono)). Myocardial efficiency was expressed in terms of the work metabolic index (WMI). P values represent overall significance from repeated measures analysis. Global LV and right ventricular (RV) MVO(2) were not significantly different between pacing modes, but the septal/lateral MVO(2) ratio differed significantly with the change in pacing mode (AAI pacing = 0.696 +/- 0.094 min(-1), simultaneous CRT = 0.975 +/- 0.143 min(-1), and sequential CRT = 0.938 +/- 0.189 min(-1); overall P = 0.001). Stroke volume index (SVI) (AAI pacing = 26.7 +/- 10.4 mL/m(2), simultaneous CRT = 30.6 +/- 11.2 mL/m(2), sequential CRT = 33.5 +/- 12.2 mL/m(2); overall P simultaneous CRT = 4.29 +/- 1.72 mmHg*mL/m(2)*10(6), sequential CRT = 4.79 +/- 1.92 mmHg*mL/m(2)*10(6); overall P = 0.002) also differed between pacing modes. Compared with simultaneous CRT, additional changes in septal/lateral MVO(2), SVI, and WMI with sequential CRT were not statistically significant on post hoc analysis. In this small selected population, CRT increases LV SVI without increasing MVO(2), resulting in improved myocardial efficiency. Additional improvements in LV work, oxidative metabolism, and efficiency from simultaneous to sequential CRT were not significant.

  19. Modelling Odor Decoding in the Antennal Lobe by Combining Sequential Firing Rate Models with Bayesian Inference.

    Directory of Open Access Journals (Sweden)

    Dario Cuevas Rivera

    2015-10-01

    Full Text Available The olfactory information that is received by the insect brain is encoded in the form of spatiotemporal patterns in the projection neurons of the antennal lobe. These dense and overlapping patterns are transformed into a sparse code in Kenyon cells in the mushroom body. Although it is clear that this sparse code is the basis for rapid categorization of odors, it is yet unclear how the sparse code in Kenyon cells is computed and what information it represents. Here we show that this computation can be modeled by sequential firing rate patterns using Lotka-Volterra equations and Bayesian online inference. This new model can be understood as an 'intelligent coincidence detector', which robustly and dynamically encodes the presence of specific odor features. We found that the model is able to qualitatively reproduce experimentally observed activity in both the projection neurons and the Kenyon cells. In particular, the model explains mechanistically how sparse activity in the Kenyon cells arises from the dense code in the projection neurons. The odor classification performance of the model proved to be robust against noise and time jitter in the observed input sequences. As in recent experimental results, we found that recognition of an odor happened very early during stimulus presentation in the model. Critically, by using the model, we found surprising but simple computational explanations for several experimental phenomena.

  20. Sequential vs simultaneous encoding of spatial information: a comparison between the blind and the sighted.

    Science.gov (United States)

    Ruotolo, Francesco; Ruggiero, Gennaro; Vinciguerra, Michela; Iachini, Tina

    2012-02-01

    The aim of this research is to assess whether the crucial factor in determining the characteristics of blind people's spatial mental images is concerned with the visual impairment per se or the processing style that the dominant perceptual modalities used to acquire spatial information impose, i.e. simultaneous (vision) vs sequential (kinaesthesis). Participants were asked to learn six positions in a large parking area via movement alone (congenitally blind, adventitiously blind, blindfolded sighted) or with vision plus movement (simultaneous sighted, sequential sighted), and then to mentally scan between positions in the path. The crucial manipulation concerned the sequential sighted group. Their visual exploration was made sequential by putting visual obstacles within the pathway in such a way that they could not see simultaneously the positions along the pathway. The results revealed a significant time/distance linear relation in all tested groups. However, the linear component was lower in sequential sighted and blind participants, especially congenital. Sequential sighted and congenitally blind participants showed an almost overlapping performance. Differences between groups became evident when mentally scanning farther distances (more than 5m). This threshold effect could be revealing of processing limitations due to the need of integrating and updating spatial information. Overall, the results suggest that the characteristics of the processing style rather than the visual impairment per se affect blind people's spatial mental images. Copyright © 2011 Elsevier B.V. All rights reserved.