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Sample records for synchronous solitary brain

  1. Outcomes of aggressive treatment in esophageal cancer patients with synchronous solitary brain metastasis.

    Science.gov (United States)

    Onal, Cem; Akkus Yildirim, Berna; Guler, Ozan Cem

    2017-07-01

    The aim of the present study was to investigate the outcomes of esophageal cancer (EC) patients with isolated synchronous brain oligometastasis (oligo-BM) treated with chemoradiotherapy (CRT) of the primary site and localized treatment of the BM with surgery, radiotherapy (RT) or radiosurgery. Of 125 EC patients investigated, seven patients (6%) had solitary BM. Six patients were diagnosed prior to, and one patient was diagnosed during, treatment. All patients were treated with neoadjuvant chemotherapy and whole-brain RT (WBRT) for BM. All but one patient received definitive CRT with a median RT dose of 50.4 Gy using conventional fractionation RT. The median age at diagnosis was 59 years (range, 48-77 years). Six patients succumbed to mortality, and one continued to receive systemic chemotherapy at the last visit. The median survival time of the patients was 18.9 months (range, 10.0-27.2 months). Median time to progression after completion of the treatments was 8 months (range, 3-9 months). Two patients had progression of the primary tumor, and one patient had progression of the BM. The neurological status of three patients with BM who were identified during the staging work-up did not deteriorate as a consequence of WBRT. In conclusion, the present study has demonstrated that aggressive treatment of the primary tumor and oligo-BM in patients with EC may prolong the survival time.

  2. Broadband criticality of human brain network synchronization.

    Science.gov (United States)

    Kitzbichler, Manfred G; Smith, Marie L; Christensen, Søren R; Bullmore, Ed

    2009-03-01

    Self-organized criticality is an attractive model for human brain dynamics, but there has been little direct evidence for its existence in large-scale systems measured by neuroimaging. In general, critical systems are associated with fractal or power law scaling, long-range correlations in space and time, and rapid reconfiguration in response to external inputs. Here, we consider two measures of phase synchronization: the phase-lock interval, or duration of coupling between a pair of (neurophysiological) processes, and the lability of global synchronization of a (brain functional) network. Using computational simulations of two mechanistically distinct systems displaying complex dynamics, the Ising model and the Kuramoto model, we show that both synchronization metrics have power law probability distributions specifically when these systems are in a critical state. We then demonstrate power law scaling of both pairwise and global synchronization metrics in functional MRI and magnetoencephalographic data recorded from normal volunteers under resting conditions. These results strongly suggest that human brain functional systems exist in an endogenous state of dynamical criticality, characterized by a greater than random probability of both prolonged periods of phase-locking and occurrence of large rapid changes in the state of global synchronization, analogous to the neuronal "avalanches" previously described in cellular systems. Moreover, evidence for critical dynamics was identified consistently in neurophysiological systems operating at frequency intervals ranging from 0.05-0.11 to 62.5-125 Hz, confirming that criticality is a property of human brain functional network organization at all frequency intervals in the brain's physiological bandwidth.

  3. Bronchogenic adenocarcinoma presenting as a synchronous solitary lytic skull lesion with ischaemic stroke--case report and literature review.

    LENUS (Irish Health Repository)

    O'Connell, David

    2011-01-01

    The authors describe a rare case of metastatic bronchogenic adenocarcinoma in a 55-year-old man presenting with concomittant solitary lytic skull lesion and ischaemic stroke. Metastatic bronchogenic carcinoma is known to present as lytic skull lesions. Primary brain tumours are also known to cause ischaemic brain injury. An underlying stroke risk may be exagerated by cranial tumour surgery. Patients with brain tumours are well known to be predisposed to an increased risk of developing thromboembolic disease. It is unusual to see metastatic bronchogenic adenocarcinoma presenting as ischaemic stroke with a background of concomittant cerebral metastasis. The aetio-pathogenesis of this rare occurrence is discussed with a review of literature.

  4. Scalp Seeding Post Craniotomy and Radiosurgery for Solitary Brain Metastasis: A Case Report and Systematic Review

    OpenAIRE

    Sharieff, Waseem; Mulroy, Liam; Weeks, Adrienne; Mansoor, Samina; Pahil, Rajbir; Islam, Muhammad U

    2017-01-01

    Background?? Radiosurgery is being increasingly used post craniotomy for brain metastasis, instead of whole-brain radiation. We report a case of scalp metastasis following craniotomy and radiosurgery, along with a systematic review of the literature. Methods???????? Our patient was a 70-year-old male who presented with a scalp metastasis, two years after craniotomy and radiosurgery, for a solitary brain metastasis from esophageal carcinoma. Using Medline? (United States National Library of Me...

  5. Fundamental Dynamical Modes Underlying Human Brain Synchronization

    Directory of Open Access Journals (Sweden)

    Catalina Alvarado-Rojas

    2012-01-01

    Full Text Available Little is known about the long-term dynamics of widely interacting cortical and subcortical networks during the wake-sleep cycle. Using large-scale intracranial recordings of epileptic patients during seizure-free periods, we investigated local- and long-range synchronization between multiple brain regions over several days. For such high-dimensional data, summary information is required for understanding and modelling the underlying dynamics. Here, we suggest that a compact yet useful representation is given by a state space based on the first principal components. Using this representation, we report, with a remarkable similarity across the patients with different locations of electrode placement, that the seemingly complex patterns of brain synchrony during the wake-sleep cycle can be represented by a small number of characteristic dynamic modes. In this space, transitions between behavioral states occur through specific trajectories from one mode to another. These findings suggest that, at a coarse level of temporal resolution, the different brain states are correlated with several dominant synchrony patterns which are successively activated across wake-sleep states.

  6. Accuracy and interobserver variation in the interpretation of computed tomography in solitary brain lesions

    NARCIS (Netherlands)

    Heimans, J. J.; de Visser, M.; Polman, C. H.; Nauta, J.; Kamphorst, W.; Troost, D.

    1990-01-01

    The clinical data and computed tomographic findings of 64 patients with solitary supratentorial brain lesions were presented to two panels of six experienced clinicians. The diagnoses predicted by these clinicians were compared with each other (interobserver variation) and with the definite

  7. Estimation of degree of synchronization in epileptic brain

    Science.gov (United States)

    Moskalenko, Olga I.; Koronovskii, Alexey A.; Pavlov, Alexey N.; Hramov, Alexander E.; Zhuravlev, Maksim O.

    2016-03-01

    The method for calculation of zero conditional Lyapunov exponent from time series has been proposed. Such method is shown to define the degree of synchronization of the regime realized in the system. It has been applied to real experimental neurophysiological time series represented by electroencephalograms of WAG/Rij rats having genetic predisposition to absence-epilepsy. The degree of synchronization in epileptic brain has been found.

  8. Practical consensus recommendations on Her2 +ve breast cancer with solitary brain mets

    Directory of Open Access Journals (Sweden)

    Nitesh Rohatgi

    2018-01-01

    Full Text Available Breast cancer is a common cause of brain metastases, with metastases occurring in at least 10–16% of patients. Longer survival of patients with metastatic breast cancer and the use of better imaging techniques are associated with an increased incidence of brain metastases. Current therapies include surgery, whole-brain radiation therapy, stereotactic radiosurgery, chemotherapy and targeted therapies. However, the timing and appropriate use of these therapies is controversial and careful patient selection by using available prognostic tools is extremely important. Expert oncologist discussed on the mode of treatment to extend the OS and improve the quality of life ofHER2-positivebreast cancer patients with Solitary brain metastases. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at this practical consensus recommendations for the benefit of community oncologists.

  9. Survival prognostic factors for patients with synchronous brain oligometastatic non-small-cell lung carcinoma receiving local therapy

    Science.gov (United States)

    Bai, Hao; Xu, Jianlin; Yang, Haitang; Jin, Bo; Lou, Yuqing; Wu, Dan; Han, Baohui

    2016-01-01

    Introduction Clinical evidence for patients with synchronous brain oligometastatic non-small-cell lung carcinoma is limited. We aimed to summarize the clinical data of these patients to explore the survival prognostic factors for this population. Methods From September 1995 to July 2011, patients with 1–3 synchronous brain oligometastases, who were treated with stereotactic radiosurgery (SRS) or surgical resection as the primary treatment, were identified at Shanghai Chest Hospital. Results A total of 76 patients (22 patients underwent brain surgery as primary treatment and 54 patients received SRS) were available for survival analysis. The overall survival (OS) for patients treated with SRS and brain surgery as the primary treatment were 12.6 months (95% confidence interval [CI] 10.3–14.9) and 16.4 months (95% CI 8.8–24.1), respectively (adjusted hazard ratio =0.59, 95% CI 0.33–1.07, P=0.08). Among 76 patients treated with SRS or brain surgery, 21 patients who underwent primary tumor resection did not experience a significantly improved OS (16.4 months, 95% CI 9.6–23.2), compared with those who did not undergo resection (11.9 months, 95% CI 9.7–14.0; adjusted hazard ratio =0.81, 95% CI 0.46–1.44, P=0.46). Factors associated with survival benefits included stage I–II of primary lung tumor and solitary brain metastasis. Conclusion There was no significant difference in OS for patients with synchronous brain oligometastasis receiving SRS or surgical resection. Among this population, the number of brain metastases and stage of primary lung disease were the factors associated with a survival benefit. PMID:27471395

  10. Solitary epidural brain metastasis of Neuroepithelioma (a Primitive Neuroectodermal Tumor: case report

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    Farnaz Farshidfar

    2008-08-01

    Full Text Available A 14 years old male was referred to Computerized tomography scan (CT of our hospital for evaluation of headache. The patient was known case of cervical soft tissue Primitive neuroectodermal tumor (PNET which has undergone surgery and radiotherapy 4 years ago. The CT scan showed large solitary extra axial, epidural lesion in right parietal region, with mass effect and bony involvement. Then surgery was done for him and the resultant biopsy was Neuroepithelioma. After diagnosis the patient has undergone chemotherapy and radiotherapy. He has no signs or symptoms of malignancy, and also follow up CT scan of the brain, chest, and abdomen were normal after two years of surgery. This is the first reported case of epidural metastasis of a head and neck PNET in an adolescent.

  11. Role of synchronized oscillatory brain activity for human pain perception.

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    Hauck, Michael; Lorenz, Jürgen; Engel, Andreas K

    2008-01-01

    The understanding of cortical pain processing in humans has significantly improved since the development of modern neuroimaging techniques. Non-invasive electrophysiological approaches such as electro- and magnetoencephalography have proven to be helpful tools for the real-time investigation of neuronal signals and synchronous communication between cortical areas. In particular, time-frequency decomposition of signals recorded with these techniques seems to be a promising approach because different pain-related oscillatory changes can be observed within different frequency bands, which are likely to be linked to specific sensory and motor functions. In this review we discuss the latest evidence on pain-induced time-frequency signals and propose that changes in oscillatory activity reflect an essential communication mechanism in the brain that is modulated during pain processing. The importance of synchronization processes for normal and pathological pain processing, such as chronic pain states, is discussed.

  12. Applying protein-based amide proton transfer MR imaging to distinguish solitary brain metastases from glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hao; Zou, Tianyu; Wang, Xianlong; Du, Yongxing; Jiang, Chunxiu; Ma, Ling; Zhu, Jianbin; He, Wen; Rui, Qihong; Wen, Zhibo [Zhujiang Hospital, Southern Medical University, Department of Radiology, Guangzhou, Guangdong (China); Lou, Huiling [The First People' Hospital of Guangzhou, Department of Geriatrics, Guangzhou, Guangdong (China); Jiang, Shanshan [Zhujiang Hospital, Southern Medical University, Department of Radiology, Guangzhou, Guangdong (China); Johns Hopkins University School of Medicine, Division of MR Research, Department of Radiology, Baltimore, MD (United States); Huang, Zhongqing [Shantou University Medical College, Department of Medical Image Center, Yuebei People' s Hospital, Shantou, Guangdong (China); Zhou, Jianyuan [Johns Hopkins University School of Medicine, Division of MR Research, Department of Radiology, Baltimore, MD (United States)

    2017-11-15

    To determine the utility of amide proton transfer-weighted (APTw) MR imaging in distinguishing solitary brain metastases (SBMs) from glioblastomas (GBMs). Forty-five patients with SBMs and 43 patients with GBMs underwent conventional and APT-weighted sequences before clinical intervention. The APTw parameters and relative APTw (rAPTw) parameters in the tumour core and the peritumoral brain zone (PBZ) were obtained and compared between SBMs and GBMs. The receiver-operating characteristic (ROC) curve was used to assess the best parameter for distinguishing between the two groups. The APTw{sub max}, APTw{sub min}, APTw{sub mean}, rAPTw{sub max}, rAPTw{sub min} or rAPTw{sub mean} values in the tumour core were not significantly different between the SBM and GBM groups (P = 0.141, 0.361, 0.221, 0.305, 0.578 and 0.448, respectively). However, the APTw{sub max}, APTw{sub min}, APTw{sub mean}, rAPTw{sub max}, rAPTw{sub min} or rAPTw{sub mean} values in the PBZ were significantly lower in the SBM group than in the GBM group (P < 0.001). The APTw{sub min} values had the highest area under the ROC curve 0.905 and accuracy 85.2% in discriminating between the two neoplasms. As a noninvasive imaging method, APT-weighted MR imaging can be used to distinguish SBMs from GBMs. (orig.)

  13. Survival prognostic factors for patients with synchronous brain oligometastatic non-small-cell lung carcinoma receiving local therapy

    Directory of Open Access Journals (Sweden)

    Bai H

    2016-07-01

    Full Text Available Hao Bai,1,* Jianlin Xu,1,* Haitang Yang,2,* Bo Jin,1 Yuqing Lou,1 Dan Wu,3 Baohui Han1 1Department of Pulmonary, 2Department of Pathology, 3Central Laboratory, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Introduction: Clinical evidence for patients with synchronous brain oligometastatic non-small-cell lung carcinoma is limited. We aimed to summarize the clinical data of these patients to explore the survival prognostic factors for this population. Methods: From September 1995 to July 2011, patients with 1–3 synchronous brain oligometastases, who were treated with stereotactic radiosurgery (SRS or surgical resection as the primary treatment, were identified at Shanghai Chest Hospital.Results: A total of 76 patients (22 patients underwent brain surgery as primary treatment and 54 patients received SRS were available for survival analysis. The overall survival (OS for patients treated with SRS and brain surgery as the primary treatment were 12.6 months (95% confidence interval [CI] 10.3–14.9 and 16.4 months (95% CI 8.8–24.1, respectively (adjusted hazard ratio =0.59, 95% CI 0.33–1.07, P=0.08. Among 76 patients treated with SRS or brain surgery, 21 patients who underwent primary tumor resection did not experience a significantly improved OS (16.4 months, 95% CI 9.6–23.2, compared with those who did not undergo resection (11.9 months, 95% CI 9.7–14.0; adjusted hazard ratio =0.81, 95% CI 0.46–1.44, P=0.46. Factors associated with survival benefits included stage I–II of primary lung tumor and solitary brain metastasis. Conclusion: There was no significant difference in OS for patients with synchronous brain oligometastasis receiving SRS or surgical resection. Among this population, the number of brain metastases and stage of primary lung disease were the factors associated with a survival benefit. Keywords: non-small-cell lung carcinoma

  14. Differentiation of solitary brain metastasis from glioblastoma multiforme: a predictive multiparametric approach using combined MR diffusion and perfusion

    International Nuclear Information System (INIS)

    Bauer, Adam Herman; Moser, Franklin G.; Maya, Marcel; Erly, William; Nael, Kambiz

    2015-01-01

    Solitary brain metastasis (MET) and glioblastoma multiforme (GBM) can appear similar on conventional MRI. The purpose of this study was to identify magnetic resonance (MR) perfusion and diffusion-weighted biomarkers that can differentiate MET from GBM. In this retrospective study, patients were included if they met the following criteria: underwent resection of a solitary enhancing brain tumor and had preoperative 3.0 T MRI encompassing diffusion tensor imaging (DTI), dynamic contrast-enhanced (DCE), and dynamic susceptibility contrast (DSC) perfusion. Using co-registered images, voxel-based fractional anisotropy (FA), mean diffusivity (MD), K trans , and relative cerebral blood volume (rCBV) values were obtained in the enhancing tumor and non-enhancing peritumoral T2 hyperintense region (NET2). Data were analyzed by logistic regression and analysis of variance. Receiver operating characteristic (ROC) analysis was performed to determine the optimal parameter/s and threshold for predicting of GBM vs. MET. Twenty-three patients (14 M, age 32-78 years old) met our inclusion criteria. Pathology revealed 13 GBMs and 10 METs. In the enhancing tumor, rCBV, K trans , and FA were higher in GBM, whereas MD was lower, neither without statistical significance. In the NET2, rCBV was significantly higher (p = 0.05) in GBM, but MD was significantly lower (p < 0.01) in GBM. FA and K trans were higher in GBM, though not reaching significance. The best discriminative power was obtained in NET2 from a combination of rCBV, FA, and MD, resulting in an area under the curve (AUC) of 0.98. The combination of MR diffusion and perfusion matrices in NET2 can help differentiate GBM over solitary MET with diagnostic accuracy of 98 %. (orig.)

  15. A network of networks model to study phase synchronization using structural connection matrix of human brain

    Science.gov (United States)

    Ferrari, F. A. S.; Viana, R. L.; Reis, A. S.; Iarosz, K. C.; Caldas, I. L.; Batista, A. M.

    2018-04-01

    The cerebral cortex plays a key role in complex cortical functions. It can be divided into areas according to their function (motor, sensory and association areas). In this paper, the cerebral cortex is described as a network of networks (cortex network), we consider that each cortical area is composed of a network with small-world property (cortical network). The neurons are assumed to have bursting properties with the dynamics described by the Rulkov model. We study the phase synchronization of the cortex network and the cortical networks. In our simulations, we verify that synchronization in cortex network is not homogeneous. Besides, we focus on the suppression of neural phase synchronization. Synchronization can be related to undesired and pathological abnormal rhythms in the brain. For this reason, we consider the delayed feedback control to suppress the synchronization. We show that delayed feedback control is efficient to suppress synchronous behavior in our network model when an appropriate signal intensity and time delay are defined.

  16. Synchronization

    Indian Academy of Sciences (India)

    Towards the end some real life exam- ples are also discussed. 1. Introduction. Synchronization, in simple terms, ..... certain relationship between their phases is termed as phase locking. GENERAL I ARTICLE ral frequencies beginning to oscillate at a common fre- quency owing to coupling is called frequency locking or.

  17. Synchronization

    Indian Academy of Sciences (India)

    When a swarm of fireflies gather, they have been found to flash in synchrony. GENERAL I ARTICLE node is due to synchronization of the rhythms of the collection of pacemaker cells. In a pathological case, the pacemaker cells become faulty which results in an abnormally low heart rate known as bradycardia. This results in ...

  18. BRAIN Journal - Some Considerations on Seriality and Synchronicity

    OpenAIRE

    Elena Nechita

    2017-01-01

    ABSTRACT This paper presents an overview of the results that have been obtained lately on seriality and synchronicity and their link, in the light of the new theories and within the frame of complexity science.

  19. Relationship of Topology, Multiscale Phase Synchronization, and State Transitions in Human Brain Networks

    Directory of Open Access Journals (Sweden)

    Minkyung Kim

    2017-06-01

    Full Text Available How the brain reconstitutes consciousness and cognition after a major perturbation like general anesthesia is an important question with significant neuroscientific and clinical implications. Recent empirical studies in animals and humans suggest that the recovery of consciousness after anesthesia is not random but ordered. Emergence patterns have been classified as progressive and abrupt transitions from anesthesia to consciousness, with associated differences in duration and electroencephalogram (EEG properties. We hypothesized that the progressive and abrupt emergence patterns from the unconscious state are associated with, respectively, continuous and discontinuous synchronization transitions in functional brain networks. The discontinuous transition is explainable with the concept of explosive synchronization, which has been studied almost exclusively in network science. We used the Kuramato model, a simple oscillatory network model, to simulate progressive and abrupt transitions in anatomical human brain networks acquired from diffusion tensor imaging (DTI of 82 brain regions. To facilitate explosive synchronization, distinct frequencies for hub nodes with a large frequency disassortativity (i.e., higher frequency nodes linking with lower frequency nodes, or vice versa were applied to the brain network. In this simulation study, we demonstrated that both progressive and abrupt transitions follow distinct synchronization processes at the individual node, cluster, and global network levels. The characteristic synchronization patterns of brain regions that are “progressive and earlier” or “abrupt but delayed” account for previously reported behavioral responses of gradual and abrupt emergence from the unconscious state. The characteristic network synchronization processes observed at different scales provide new insights into how regional brain functions are reconstituted during progressive and abrupt emergence from the unconscious

  20. Failure of delayed feedback deep brain stimulation for intermittent pathological synchronization in Parkinson's disease.

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    Andrey Dovzhenok

    Full Text Available Suppression of excessively synchronous beta-band oscillatory activity in the brain is believed to suppress hypokinetic motor symptoms of Parkinson's disease. Recently, a lot of interest has been devoted to desynchronizing delayed feedback deep brain stimulation (DBS. This type of synchrony control was shown to destabilize the synchronized state in networks of simple model oscillators as well as in networks of coupled model neurons. However, the dynamics of the neural activity in Parkinson's disease exhibits complex intermittent synchronous patterns, far from the idealized synchronous dynamics used to study the delayed feedback stimulation. This study explores the action of delayed feedback stimulation on partially synchronized oscillatory dynamics, similar to what one observes experimentally in parkinsonian patients. We employ a computational model of the basal ganglia networks which reproduces experimentally observed fine temporal structure of the synchronous dynamics. When the parameters of our model are such that the synchrony is unphysiologically strong, the feedback exerts a desynchronizing action. However, when the network is tuned to reproduce the highly variable temporal patterns observed experimentally, the same kind of delayed feedback may actually increase the synchrony. As network parameters are changed from the range which produces complete synchrony to those favoring less synchronous dynamics, desynchronizing delayed feedback may gradually turn into synchronizing stimulation. This suggests that delayed feedback DBS in Parkinson's disease may boost rather than suppress synchronization and is unlikely to be clinically successful. The study also indicates that delayed feedback stimulation may not necessarily exhibit a desynchronization effect when acting on a physiologically realistic partially synchronous dynamics, and provides an example of how to estimate the stimulation effect.

  1. Differential synchronization in default and task-specific networks of the human brain

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    Aaron eKirschner

    2012-05-01

    Full Text Available On a regional scale the brain is organized into dynamic functional networks. The activity within one of these, the default network, can be dissociated from that in other task-specific networks. All brain networks are connected structurally, but evidently are only transiently connected functionally. One hypothesis as to how such transient functional coupling occurs is that network formation and dissolution is mediated, or at least accompanied, by increases and decreases in oscillatory synchronization between constituent brain regions. If so, then we should be able to find transient differences in intra-network synchronization between the default network and a task-specific network. In order to investigate this hypothesis we conducted two experiments in which subjects engaged in a Sustained Attention to Response Task (SART while having brain activity recorded via high-density electroencephalography (EEG. We found that during periods when attention was focused internally (mind-wandering there was significantly more neural phase synchronization between brain regions associated with the default network, whereas during periods when subjects were focused on performing the visual task there was significantly more neural phase synchrony within a task-specific brain network that shared some of the same brain regions. These differences in network synchrony occurred in each of theta, alpha, and gamma frequency bands. A similar pattern of differential oscillatory power changes, indicating modulation of local synchronization by attention state, was also found. These results provide further evidence that the human brain is intrinsically organized into default and task-specific brain networks, and confirm that oscillatory synchronization is a potential mechanism for functional coupling within these networks.

  2. Neural dynamics in Parkinsonian brain: The boundary between synchronized and nonsynchronized dynamics

    Science.gov (United States)

    Park, Choongseok; Worth, Robert M.; Rubchinsky, Leonid L.

    2011-04-01

    Synchronous oscillatory dynamics is frequently observed in the human brain. We analyze the fine temporal structure of phase-locking in a realistic network model and match it with the experimental data from Parkinsonian patients. We show that the experimentally observed intermittent synchrony can be generated just by moderately increased coupling strength in the basal ganglia circuits due to the lack of dopamine. Comparison of the experimental and modeling data suggest that brain activity in Parkinson's disease resides in the large boundary region between synchronized and nonsynchronized dynamics. Being on the edge of synchrony may allow for easy formation of transient neuronal assemblies.

  3. Inter-subject synchronization of brain responses during natural music listening.

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    Abrams, Daniel A; Ryali, Srikanth; Chen, Tianwen; Chordia, Parag; Khouzam, Amirah; Levitin, Daniel J; Menon, Vinod

    2013-05-01

    Music is a cultural universal and a rich part of the human experience. However, little is known about common brain systems that support the processing and integration of extended, naturalistic 'real-world' music stimuli. We examined this question by presenting extended excerpts of symphonic music, and two pseudomusical stimuli in which the temporal and spectral structure of the Natural Music condition were disrupted, to non-musician participants undergoing functional brain imaging and analysing synchronized spatiotemporal activity patterns between listeners. We found that music synchronizes brain responses across listeners in bilateral auditory midbrain and thalamus, primary auditory and auditory association cortex, right-lateralized structures in frontal and parietal cortex, and motor planning regions of the brain. These effects were greater for natural music compared to the pseudo-musical control conditions. Remarkably, inter-subject synchronization in the inferior colliculus and medial geniculate nucleus was also greater for the natural music condition, indicating that synchronization at these early stages of auditory processing is not simply driven by spectro-temporal features of the stimulus. Increased synchronization during music listening was also evident in a right-hemisphere fronto-parietal attention network and bilateral cortical regions involved in motor planning. While these brain structures have previously been implicated in various aspects of musical processing, our results are the first to show that these regions track structural elements of a musical stimulus over extended time periods lasting minutes. Our results show that a hierarchical distributed network is synchronized between individuals during the processing of extended musical sequences, and provide new insight into the temporal integration of complex and biologically salient auditory sequences. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  4. Inter-subject synchronization of brain responses during natural music listening

    Science.gov (United States)

    Abrams, Daniel A.; Ryali, Srikanth; Chen, Tianwen; Chordia, Parag; Khouzam, Amirah; Levitin, Daniel J.; Menon, Vinod

    2015-01-01

    Music is a cultural universal and a rich part of the human experience. However, little is known about common brain systems that support the processing and integration of extended, naturalistic ‘real-world’ music stimuli. We examined this question by presenting extended excerpts of symphonic music, and two pseudomusical stimuli in which the temporal and spectral structure of the Natural Music condition were disrupted, to non-musician participants undergoing functional brain imaging and analysing synchronized spatiotemporal activity patterns between listeners. We found that music synchronizes brain responses across listeners in bilateral auditory midbrain and thalamus, primary auditory and auditory association cortex, right-lateralized structures in frontal and parietal cortex, and motor planning regions of the brain. These effects were greater for natural music compared to the pseudo-musical control conditions. Remarkably, inter-subject synchronization in the inferior colliculus and medial geniculate nucleus was also greater for the natural music condition, indicating that synchronization at these early stages of auditory processing is not simply driven by spectro-temporal features of the stimulus. Increased synchronization during music listening was also evident in a right-hemisphere fronto-parietal attention network and bilateral cortical regions involved in motor planning. While these brain structures have previously been implicated in various aspects of musical processing, our results are the first to show that these regions track structural elements of a musical stimulus over extended time periods lasting minutes. Our results show that a hierarchical distributed network is synchronized between individuals during the processing of extended musical sequences, and provide new insight into the temporal integration of complex and biologically salient auditory sequences. PMID:23578016

  5. Structure function relationship in complex brain networks expressed by hierarchical synchronization

    Science.gov (United States)

    Zhou, Changsong; Zemanová, Lucia; Zamora-López, Gorka; Hilgetag, Claus C.; Kurths, Jürgen

    2007-06-01

    The brain is one of the most complex systems in nature, with a structured complex connectivity. Recently, large-scale corticocortical connectivities, both structural and functional, have received a great deal of research attention, especially using the approach of complex network analysis. Understanding the relationship between structural and functional connectivity is of crucial importance in neuroscience. Here we try to illuminate this relationship by studying synchronization dynamics in a realistic anatomical network of cat cortical connectivity. We model the nodes (cortical areas) by a neural mass model (population model) or by a subnetwork of interacting excitable neurons (multilevel model). We show that if the dynamics is characterized by well-defined oscillations (neural mass model and subnetworks with strong couplings), the synchronization patterns are mainly determined by the node intensity (total input strengths of a node) and the detailed network topology is rather irrelevant. On the other hand, the multilevel model with weak couplings displays more irregular, biologically plausible dynamics, and the synchronization patterns reveal a hierarchical cluster organization in the network structure. The relationship between structural and functional connectivity at different levels of synchronization is explored. Thus, the study of synchronization in a multilevel complex network model of cortex can provide insights into the relationship between network topology and functional organization of complex brain networks.

  6. Synchronicity from Synchronized Chaos

    Directory of Open Access Journals (Sweden)

    Gregory S. Duane

    2015-03-01

    Full Text Available The synchronization of loosely-coupled chaotic oscillators, a phenomenon investigated intensively for the last two decades, may realize the philosophical concept of “synchronicity”—the commonplace notion that related eventsmysteriously occur at the same time. When extended to continuous media and/or large discrete arrays, and when general (non-identical correspondences are considered between states, intermittent synchronous relationships indeed become ubiquitous. Meaningful synchronicity follows naturally if meaningful events are identified with coherent structures, defined by internal synchronization between remote degrees of freedom; a condition that has been posited as necessary for synchronizability with an external system. The important case of synchronization between mind and matter is realized if mind is analogized to a computer model, synchronizing with a sporadically observed system, as in meteorological data assimilation. Evidence for the ubiquity of synchronization is reviewed along with recent proposals that: (1 synchronization of different models of the same objective process may be an expeditious route to improved computational modeling and may also describe the functioning of conscious brains; and (2 the nonlocality in quantum phenomena implied by Bell’s theorem may be explained in a variety of deterministic (hidden variable interpretations if the quantum world resides on a generalized synchronization “manifold”.

  7. Analysis of a phase synchronized functional network based on the rhythm of brain activities

    International Nuclear Information System (INIS)

    Li Ling; Jin Zhen-Lan; Li Bin

    2011-01-01

    Rhythm of brain activities represents oscillations of postsynaptic potentials in neocortex, therefore it can serve as an indicator of the brain activity state. In order to check the connectivity of brain rhythm, this paper develops a new method of constructing functional network based on phase synchronization. Electroencephalogram (EEG) data were collected while subjects looking at a green cross in two states, performing an attention task and relaxing with eyes-open. The EEG from these two states was filtered by three band-pass filters to obtain signals of theta (4–7 Hz), alpha (8–13 Hz) and beta (14–30 Hz) bands. Mean resultant length was used to estimate strength of phase synchronization in three bands to construct networks of both states, and mean degree K and cluster coefficient C of networks were calculated as a function of threshold. The result shows higher cluster coefficient in the attention state than in the eyes-open state in all three bands, suggesting that cluster coefficient reflects brain state. In addition, an obvious fronto-parietal network is found in the attention state, which is a well-known attention network. These results indicate that attention modulates the fronto-parietal connectivity in different modes as compared with the eyes-open state. Taken together this method is an objective and important tool to study the properties of neural networks of brain rhythm. (interdisciplinary physics and related areas of science and technology)

  8. Embolic Brain Infarcts: A Rare Fatal Complication of Preoperative Embolization of a Massive Solitary Fibrous Tumor of the Pleura

    International Nuclear Information System (INIS)

    Patel, Shreyas R.; Vachhani, Prasann; Moeslein, Fred

    2017-01-01

    Solitary fibrous tumor of the pleura (SFTP) is a rare intrathoracic neoplasm, often giant in size and highly vascular, which can make surgical resection very challenging. Preoperative percutaneous embolization before surgical removal can significantly reduce the risk of uncontrollable intraoperative hemorrhage. However, a rare potential life threatening complication could result from embolization of SFTP and must be taken into consideration. This report describes a 69-year-old female with a large right thoracic SFTP, who underwent preoperative angiography and embolization and developed diffuse embolic brain infarcts immediately after the administration of polyvinyl alcohol particles.

  9. Embolic Brain Infarcts: A Rare Fatal Complication of Preoperative Embolization of a Massive Solitary Fibrous Tumor of the Pleura

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Shreyas R., E-mail: Shrey000@gmail.com; Vachhani, Prasann; Moeslein, Fred [University of Maryland Medical Center, Department of Diagnostic Radiology and Nuclear Medicine (United States)

    2017-02-15

    Solitary fibrous tumor of the pleura (SFTP) is a rare intrathoracic neoplasm, often giant in size and highly vascular, which can make surgical resection very challenging. Preoperative percutaneous embolization before surgical removal can significantly reduce the risk of uncontrollable intraoperative hemorrhage. However, a rare potential life threatening complication could result from embolization of SFTP and must be taken into consideration. This report describes a 69-year-old female with a large right thoracic SFTP, who underwent preoperative angiography and embolization and developed diffuse embolic brain infarcts immediately after the administration of polyvinyl alcohol particles.

  10. Pink noise: effect on complexity synchronization of brain activity and sleep consolidation.

    Science.gov (United States)

    Zhou, Junhong; Liu, Dongdong; Li, Xin; Ma, Jing; Zhang, Jue; Fang, Jing

    2012-08-07

    In this study, we hypothesized that steady pink noise is able to change the complexity of brain activities into a characteristic level and it might have significant effect on improving sleep stability. First, we carried out the brain synchronization test in which electroencephalogram (EEG) signals of 6 subjects were recorded. The whole experiment procedure was divided into 5 blocks in the alternative feeding process of 10-min quiet and 10-min noise. After the complexity analysis of fractal dimension, we found that the complexity of the EEG signals decreased with the introduction of the pink noise exposure, showing the brain waves tended to synchronize with the pink noise induction to reach a low level. For the sleep quality experiment, 40 subjects were recruited the group of nocturnal sleep experiment and 10 participants were chosen for nap test. Each subjects slept for two consecutive experimental periods, of which one is pink noise exposed and the other is quiet. For both nocturnal sleep and nap tests, the results in the noise exposure group showed significant enhancement in the percentage of stable sleep time compared to the control group based on the analysis of electrocardiography (ECG) signal with cardiopulmonary coupling approach. This study demonstrates that steady pink noise has significant effect on reducing brain wave complexity and inducing more stable sleep time to improve sleep quality of individuals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. A Synchronous Motor Imagery Based Neural Physiological Paradigm for Brain Computer Interface Speller

    Directory of Open Access Journals (Sweden)

    Lei Cao

    2017-05-01

    Full Text Available Brain Computer Interface (BCI speller is a typical BCI-based application to help paralyzed patients express their thoughts. This paper proposed a novel motor imagery based BCI speller with Oct-o-spell paradigm for word input. Furthermore, an intelligent input method was used for improving the performance of the BCI speller. For the English word spelling experiment, we compared synchronous control with previous asynchronous control under the same experimental condition. There were no significant differences between these two control methods in the classification accuracy, information transmission rate (ITR or letters per minute (LPM. And the accuracy rates of over 70% validated the feasibility for these two control strategies. It was indicated that MI-based synchronous control protocol was feasible for BCI speller. And the efficiency of the predictive text entry (PTE mode was superior to that of the Non-PTE mode.

  12. Time and frequency-dependent modulation of local field potential synchronization by deep brain stimulation.

    Directory of Open Access Journals (Sweden)

    Clinton B McCracken

    Full Text Available High-frequency electrical stimulation of specific brain structures, known as deep brain stimulation (DBS, is an effective treatment for movement disorders, but mechanisms of action remain unclear. We examined the time-dependent effects of DBS applied to the entopeduncular nucleus (EP, the rat homolog of the internal globus pallidus, a target used for treatment of both dystonia and Parkinson's disease (PD. We performed simultaneous multi-site local field potential (LFP recordings in urethane-anesthetized rats to assess the effects of high-frequency (HF, 130 Hz; clinically effective, low-frequency (LF, 15 Hz; ineffective and sham DBS delivered to EP. LFP activity was recorded from dorsal striatum (STR, ventroanterior thalamus (VA, primary motor cortex (M1, and the stimulation site in EP. Spontaneous and acute stimulation-induced LFP oscillation power and functional connectivity were assessed at baseline, and after 30, 60, and 90 minutes of stimulation. HF EP DBS produced widespread alterations in spontaneous and stimulus-induced LFP oscillations, with some effects similar across regions and others occurring in a region- and frequency band-specific manner. Many of these changes evolved over time. HF EP DBS produced an initial transient reduction in power in the low beta band in M1 and STR; however, phase synchronization between these regions in the low beta band was markedly suppressed at all time points. DBS also enhanced low gamma synchronization throughout the circuit. With sustained stimulation, there were significant reductions in low beta synchronization between M1-VA and STR-VA, and increases in power within regions in the faster frequency bands. HF DBS also suppressed the ability of acute EP stimulation to induce beta oscillations in all regions along the circuit. This dynamic pattern of synchronizing and desynchronizing effects of EP DBS suggests a complex modulation of activity along cortico-BG-thalamic circuits underlying the therapeutic

  13. How Two Brains Make One Synchronized Mind in the Inferior Frontal Cortex: fNIRS-Based Hyperscanning During Cooperative Singing.

    Science.gov (United States)

    Osaka, Naoyuki; Minamoto, Takehiro; Yaoi, Ken; Azuma, Miyuki; Shimada, Yohko Minamoto; Osaka, Mariko

    2015-01-01

    One form of communication that is common in all cultures is people singing together. Singing together reflects an index of cognitive synchronization and cooperation of human brains. Little is known about the neural synchronization mechanism, however. Here, we examined how two brains make one synchronized behavior using cooperated singing/humming between two people and hyperscanning, a new brain scanning technique. Hyperscanning allowed us to observe dynamic cooperation between interacting participants. We used functional near-infrared spectroscopy (fNIRS) to simultaneously record the brain activity of two people while they cooperatively sang or hummed a song in face-to-face (FtF) or face-to-wall (FtW) conditions. By calculating the inter-brain wavelet transform coherence between two interacting brains, we found a significant increase in the neural synchronization of the left inferior frontal cortex (IFC) for cooperative singing or humming regardless of FtF or FtW compared with singing or humming alone. On the other hand, the right IFC showed an increase in neural synchronization for humming only, possibly due to more dependence on musical processing.

  14. Solitary pulmonary nodule

    Science.gov (United States)

    Lung cancer - solitary nodule; Infectious granuloma - pulmonary nodule; SPN ... More than half of all solitary pulmonary nodules are noncancerous ... infections. Infectious granulomas (which are formed by cells as ...

  15. Interneuron Deficit Associates Attenuated Network Synchronization to Mismatch of Energy Supply and Demand in Aging Mouse Brains

    DEFF Research Database (Denmark)

    Jessen, Sanne Barsballe; Mathiesen, Claus; Lind, Barbara Lykke

    2017-01-01

    Higher cognitive functions depend critically on synchronized network activity in the gamma range (30-100 Hz), which results from activity of fast-spiking parvalbumin-positive (PV) interneurons. Here, we examined synaptic activity in the gamma band in relation to PV interneuron activity, stimulati...... and CMRO2 responses may contribute to increased frailty and risk of cognitive decline in aged brains....

  16. Power law scaling in synchronization of brain signals depends on cognitive load.

    Science.gov (United States)

    Tinker, Jesse; Velazquez, Jose Luis Perez

    2014-01-01

    As it has several features that optimize information processing, it has been proposed that criticality governs the dynamics of nervous system activity. Indications of such dynamics have been reported for a variety of in vitro and in vivo recordings, ranging from in vitro slice electrophysiology to human functional magnetic resonance imaging. However, there still remains considerable debate as to whether the brain actually operates close to criticality or in another governing state such as stochastic or oscillatory dynamics. A tool used to investigate the criticality of nervous system data is the inspection of power-law distributions. Although the findings are controversial, such power-law scaling has been found in different types of recordings. Here, we studied whether there is a power law scaling in the distribution of the phase synchronization derived from magnetoencephalographic recordings during executive function tasks performed by children with and without autism. Characterizing the brain dynamics that is different between autistic and non-autistic individuals is important in order to find differences that could either aid diagnosis or provide insights as to possible therapeutic interventions in autism. We report in this study that power law scaling in the distributions of a phase synchrony index is not very common and its frequency of occurrence is similar in the control and the autism group. In addition, power law scaling tends to diminish with increased cognitive load (difficulty or engagement in the task). There were indications of changes in the probability distribution functions for the phase synchrony that were associated with a transition from power law scaling to lack of power law (or vice versa), which suggests the presence of phenomenological bifurcations in brain dynamics associated with cognitive load. Hence, brain dynamics may fluctuate between criticality and other regimes depending upon context and behaviors.

  17. Power law scaling in synchronization of brain signals depends on cognitive load

    Directory of Open Access Journals (Sweden)

    Jose Luis ePerez Velazquez

    2014-05-01

    Full Text Available As it has several features that optimize information processing, it has been proposed that criticality governs the dynamics of nervous system activity. Indications of such dynamics have been reported for a variety of in vitro and in vivo recordings, ranging from in vitro slice electrophysiology to human functional magnetic resonance imaging. However, there still remains considerable debate as to whether the brain actually operates close to criticality or in another governing state such as stochastic or oscillatory dynamics. A tool used to investigate the criticality of nervous system data is the inspection of power-law distributions. Although the findings are controversial, such power-law scaling has been found in different types of recordings. Here, we studied whether there is a power law scaling in the distribution of the phase synchronization derived from magnetoencephalographic recordings during executive function tasks performed by children with and without autism. Characterizing the brain dynamics that is different between autistic and non-autistic individuals is important in order to find differences that could either aid diagnosis or provide insights as to possible therapeutic interventions in autism. We report in this study that power law scaling in the distributions of a phase synchrony index is not very common and its frequency of occurrence is similar in the control and the autism group. In addition, power law scaling tends to diminish with increased cognitive load (difficulty or engagement in the task. There were indications of changes in the probability distribution functions for the phase synchrony that were associated with a transition from power law scaling to lack of power law (or vice versa, which suggests the presence of phenomenological bifurcations in brain dynamics associated with cognitive load. Hence, brain dynamics may fluctuate between criticality and other regimes depending upon context and behaviours.

  18. Synchronous brain activity during cooperative exchange depends on gender of partner: A fNIRS-based hyperscanning study.

    Science.gov (United States)

    Cheng, Xiaojun; Li, Xianchun; Hu, Yi

    2015-06-01

    Previous studies have shown that brain activity between partners is synchronized during cooperative exchange. Whether this neural synchronization depends on the gender of partner (i.e., opposite or same to the participant) is open to be explored. In current study, we used functional near-infrared spectroscopy (fNIRS) based hyperscanning to study cooperation in a two-person game (female-female, female-male, and male-male) while assaying brain-to-brain interactions. Cooperation was greater in male-male pairs than in female-female pairs, with intermediate cooperation levels for female-male pairs. More importantly, in dyads with partners with opposite gender (female-male pairs), we found significant task-related cross-brain coherence in frontal regions (i.e., frontopolar cortex, orbitofrontal cortex, and left dorsolateral prefrontal cortex) whereas the cooperation in same gender dyads (female-female pairs and male-male pairs) was not associated with such synchronization. Moreover, the changes of such interbrain coherence across task blocks were significantly correlated with change in degree of cooperation only in mixed-sex dyads. These findings suggested that different neural processes underlie cooperation between mixed-sex and same-sex dyadic interactions. © 2015 Wiley Periodicals, Inc.

  19. Alpha synchronization as a brain model for unconscious defense: An overview of the work of Howard Shevrin and his team.

    Science.gov (United States)

    Bazan, Ariane

    2017-10-01

    Howard Shevrin and his team have developed a stringent subliminal priming methodology, which experimentally approximates a situation of an internal, mental triggering of unconscious defense. Through a series of four studies they thus are able to bring evidence for this type of unconscious defense. With event-related potentials, three clinical studies show how synchronization of a specific brain wave, the alpha wave, known for its inhibitory function, is also induced by subliminally presented conflictual subject-specific stimuli. Therefore, alpha synchronization could serve as the brain mechanism of unconscious defense. The results only make sense if we suppose the existence of a dynamic unconscious, which has inherited childhood conflicts, and with privileged connections to neurotic symptom characteristics. Moreover, by showing that the unconscious conflict phrases, inferred by clinicians from clinical interviews, have a similar brain behavior, Shevrin and his team provide evidence that these inferences are not simply clinician-dependent subjective interpretations but also imply some form of independent mental reality. Finally, interpretation of the results has led us to propose two distinct physiological mechanisms for defense: one, unconscious defense, by alpha synchronization in connection with the drive derivatives, and another, repression, based on the indications of reality in connection with the ego. Copyright © 2017 Institute of Psychoanalysis.

  20. Fast sparsely synchronized brain rhythms in a scale-free neural network.

    Science.gov (United States)

    Kim, Sang-Yoon; Lim, Woochang

    2015-08-01

    We consider a directed version of the Barabási-Albert scale-free network model with symmetric preferential attachment with the same in- and out-degrees and study the emergence of sparsely synchronized rhythms for a fixed attachment degree in an inhibitory population of fast-spiking Izhikevich interneurons. Fast sparsely synchronized rhythms with stochastic and intermittent neuronal discharges are found to appear for large values of J (synaptic inhibition strength) and D (noise intensity). For an intensive study we fix J at a sufficiently large value and investigate the population states by increasing D. For small D, full synchronization with the same population-rhythm frequency fp and mean firing rate (MFR) fi of individual neurons occurs, while for large D partial synchronization with fp>〈fi〉 (〈fi〉: ensemble-averaged MFR) appears due to intermittent discharge of individual neurons; in particular, the case of fp>4〈fi〉 is referred to as sparse synchronization. For the case of partial and sparse synchronization, MFRs of individual neurons vary depending on their degrees. As D passes a critical value D* (which is determined by employing an order parameter), a transition to unsynchronization occurs due to the destructive role of noise to spoil the pacing between sparse spikes. For Dsynchronization emerges in the whole population because the spatial correlation length between the neuronal pairs covers the whole system. Furthermore, the degree of population synchronization is also measured in terms of two types of realistic statistical-mechanical measures. Only for the partial and sparse synchronization do contributions of individual neuronal dynamics to population synchronization change depending on their degrees, unlike in the case of full synchronization. Consequently, dynamics of individual neurons reveal the inhomogeneous network structure for the case of partial and sparse synchronization, which is in contrast to the case of

  1. Atypical Bilateral Brain Synchronization in the Early Stage of Human Voice Auditory Processing in Young Children with Autism.

    Directory of Open Access Journals (Sweden)

    Toshiharu Kurita

    Full Text Available Autism spectrum disorder (ASD has been postulated to involve impaired neuronal cooperation in large-scale neural networks, including cortico-cortical interhemispheric circuitry. In the context of ASD, alterations in both peripheral and central auditory processes have also attracted a great deal of interest because these changes appear to represent pathophysiological processes; therefore, many prior studies have focused on atypical auditory responses in ASD. The auditory evoked field (AEF, recorded by magnetoencephalography, and the synchronization of these processes between right and left hemispheres was recently suggested to reflect various cognitive abilities in children. However, to date, no previous study has focused on AEF synchronization in ASD subjects. To assess global coordination across spatially distributed brain regions, the analysis of Omega complexity from multichannel neurophysiological data was proposed. Using Omega complexity analysis, we investigated the global coordination of AEFs in 3-8-year-old typically developing (TD children (n = 50 and children with ASD (n = 50 in 50-ms time-windows. Children with ASD displayed significantly higher Omega complexities compared with TD children in the time-window of 0-50 ms, suggesting lower whole brain synchronization in the early stage of the P1m component. When we analyzed the left and right hemispheres separately, no significant differences in any time-windows were observed. These results suggest lower right-left hemispheric synchronization in children with ASD compared with TD children. Our study provides new evidence of aberrant neural synchronization in young children with ASD by investigating auditory evoked neural responses to the human voice.

  2. [Adenocarcinoma of lung cancer with solitary metastasis to the stomach].

    Science.gov (United States)

    Koh, Sung Ae; Lee, Kyung Hee

    2014-09-25

    Although hematogenous metastasis of cancer to the gastrointestinal track is rare, it sometime has been reported in patients with malignant melanoma and breast cancer. However, it is extremely rare for lung cancer to metastasize to the stomach, not to mention solitary gastric metastasis. Herein, the authors report a case of a 69-year-old man who was initially diagnosed with lung cancer with synchronous primary gastric cancer which proved to be lung cancer with solitary gastric metastasis after the operation.

  3. Brain network dynamics characterization in epileptic seizures. Joint directed graph and pairwise synchronization measures

    Science.gov (United States)

    Rodrigues, A. C.; Machado, B. S.; Florence, G.; Hamad, A. P.; Sakamoto, A. C.; Fujita, A.; Baccalá, L. A.; Amaro, E.; Sameshima, K.

    2014-12-01

    Here we propose and evaluate a new approach to analyse multichannel mesial temporal lobe epilepsy EEG data from eight patients through complex network and synchronization theories. The method employs a Granger causality test to infer the directed connectivity graphs and a wavelet transform based phase synchronization measure whose characteristics allow studying dynamical transitions during epileptic seizures. We present a new combined graph measure that quantifies the level of network hub formation, called network hub out-degree, which closely reflects the level of synchronization observed during the ictus.

  4. Solitary black pigment stones

    International Nuclear Information System (INIS)

    Wolpers, C.; Wosiewitz, U.

    1986-01-01

    Solitary pigment stones of the gall-bladder are rare (1.7%). 82,5% are radiopaque, 17.5% radiolucent. 64,8% of radiopaque solitary pigment stones have the structure of a cockade. Such cockades take years to develop. Solitary cholesterol stones with a nucleus of a radiopaque pigment stone should not be treated for litholysis. 8% of solitary cholesterol stones with a cross diameter below 15 mm. possess a radiolucent pigment stone nucleus. X-ray diagnosis for selecting litholytic treatment remains the safest method, especially if the radiologist compares his films regularly with the specimens after surgery. (orig.) [de

  5. Fast sparsely synchronized brain rhythms in a scale-free neural network

    Science.gov (United States)

    Kim, Sang-Yoon; Lim, Woochang

    2015-08-01

    We consider a directed version of the Barabási-Albert scale-free network model with symmetric preferential attachment with the same in- and out-degrees and study the emergence of sparsely synchronized rhythms for a fixed attachment degree in an inhibitory population of fast-spiking Izhikevich interneurons. Fast sparsely synchronized rhythms with stochastic and intermittent neuronal discharges are found to appear for large values of J (synaptic inhibition strength) and D (noise intensity). For an intensive study we fix J at a sufficiently large value and investigate the population states by increasing D . For small D , full synchronization with the same population-rhythm frequency fp and mean firing rate (MFR) fi of individual neurons occurs, while for large D partial synchronization with fp> ( : ensemble-averaged MFR) appears due to intermittent discharge of individual neurons; in particular, the case of fp>4 is referred to as sparse synchronization. For the case of partial and sparse synchronization, MFRs of individual neurons vary depending on their degrees. As D passes a critical value D* (which is determined by employing an order parameter), a transition to unsynchronization occurs due to the destructive role of noise to spoil the pacing between sparse spikes. For D change depending on their degrees, unlike in the case of full synchronization. Consequently, dynamics of individual neurons reveal the inhomogeneous network structure for the case of partial and sparse synchronization, which is in contrast to the case of statistically homogeneous random graphs and small-world networks. Finally, we investigate the effect of network architecture on sparse synchronization for fixed values of J and D in the following three cases: (1) variation in the degree of symmetric attachment, (2) asymmetric preferential attachment of new nodes with different in- and out-degrees, and (3) preferential attachment between pre-existing nodes (without addition of new nodes). In these

  6. Bumblebees and solitary bees

    DEFF Research Database (Denmark)

    Henriksen, Casper Christian I

    organic fields than in those bordering conventional fields. This was due to the absence of herbicides and to practices inherent to organic farming systems, such as use of clover (a high value bee plant) as a green manure and fodder crop. Solitary bees responded with significantly higher numbers......Summary: The effects of farming system, flower resources and semi-natural habitats on bumblebees and solitary bees in intensively cultivated landscapes in Denmark were investigated in two sets of studies, in 2011 and 2012. The pan trap colour preferences of bumblebees and solitary bees were also...... use as a proxy at four different scales (250, 500, 750 and 1000 m). In 2012, the effect of a four-fold larger area of organic arable fields in simple, homogeneous landscapes on bumblebees and solitary bees was investigated in eight circular landscapes (radius 1000 m). Bumblebees and solitary bees were...

  7. Bumblebees and solitary bees

    DEFF Research Database (Denmark)

    Henriksen, Casper Christian I

    Summary: The effects of farming system, flower resources and semi-natural habitats on bumblebees and solitary bees in intensively cultivated landscapes in Denmark were investigated in two sets of studies, in 2011 and 2012. The pan trap colour preferences of bumblebees and solitary bees were also...... assessed. In 2011, bumblebees and solitary bees were trapped in road verges bordering 14 organic (organic sites) and 14 conventional (conventional sites) winter wheat fields. The quantity and quality of local flower resources in the road verge and adjacent field headland were estimated as overall density...... use as a proxy at four different scales (250, 500, 750 and 1000 m). In 2012, the effect of a four-fold larger area of organic arable fields in simple, homogeneous landscapes on bumblebees and solitary bees was investigated in eight circular landscapes (radius 1000 m). Bumblebees and solitary bees were...

  8. Solitary waves in fluids

    CERN Document Server

    Grimshaw, RHJ

    2007-01-01

    After the initial observation by John Scott Russell of a solitary wave in a canal, his insightful laboratory experiments and the subsequent theoretical work of Boussinesq, Rayleigh and Korteweg and de Vries, interest in solitary waves in fluids lapsed until the mid 1960's with the seminal paper of Zabusky and Kruskal describing the discovery of the soliton. This was followed by the rapid development of the theory of solitons and integrable systems. At the same time came the realization that solitary waves occur naturally in many physical systems, and play a fundamental role in many circumstances. The aim of this text is to describe the role that soliton theory plays in fluids in several contexts. After an historical introduction, the book is divided five chapters covering the basic theory of the Korteweg-de Vries equation, and the subsequent application to free-surface solitary waves in water to internal solitary waves in the coastal ocean and the atmospheric boundary layer, solitary waves in rotating flows, ...

  9. Synchronizing an aging brain: can entraining circadian clocks by food slow Alzheimer's disease?

    Science.gov (United States)

    Kent, Brianne A

    2014-01-01

    Alzheimer's disease (AD) is a global epidemic. Unfortunately, we are still without effective treatments or a cure for this disease, which is having devastating consequences for patients, their families, and societies around the world. Until effective treatments are developed, promoting overall health may hold potential for delaying the onset or preventing neurodegenerative diseases such as AD. In particular, chronobiological concepts may provide a useful framework for identifying the earliest signs of age-related disease as well as inexpensive and noninvasive methods for promoting health. It is well reported that AD is associated with disrupted circadian functioning to a greater extent than normal aging. However, it is unclear if the central circadian clock (i.e., the suprachiasmatic nucleus) is dysfunctioning, or whether the synchrony between the central and peripheral clocks that control behavior and metabolic processes are becoming uncoupled. Desynchrony of rhythms can negatively affect health, increasing morbidity and mortality in both animal models and humans. If the uncoupling of rhythms is contributing to AD progression or exacerbating symptoms, then it may be possible to draw from the food-entrainment literature to identify mechanisms for re-synchronizing rhythms to improve overall health and reduce the severity of symptoms. The following review will briefly summarize the circadian system, its potential role in AD, and propose using a feeding-related neuropeptide, such as ghrelin, to synchronize uncoupled rhythms. Synchronizing rhythms may be an inexpensive way to promote healthy aging and delay the onset of neurodegenerative disease such as AD.

  10. Phase synchronization for classification of spontaneous EEG signals in brain-computer interfaces

    OpenAIRE

    Gysels, Elly; Kunt, Murat; Celka, Patrick

    2007-01-01

    By directly analyzing brain activity, Brain-Computer Interfaces (BCIs) allow for communication that does not rely on any muscular control and therefore constitute a possible communication channel for the completely paralyzed. Typically, the user performs different mental tasks, that correspond to different output commands as recognized by the system. From the recorded brain signals (Electroencephalogram, EEG), features that characterize the mental tasks and allow their discrimination by a cla...

  11. Phase synchronization for classification of spontaneous EEG signals in brain-computer interfaces

    OpenAIRE

    Gysels, Elly

    2005-01-01

    By directly analyzing brain activity, Brain-Computer Interfaces (BCIs) allow for communication that does not rely on any muscular control and therefore constitute a possible communication channel for the completely paralyzed. Typically, the user performs different mental tasks, that correspond to different output commands as recognized by the system. From the recorded brain signals (Electroencephalogram, EEG), features that characterize the mental tasks and allow their discrimination by a cla...

  12. Why Do We Fall into Sync with Others? Interpersonal Synchronization and the Brain's Optimization Principle

    DEFF Research Database (Denmark)

    Koban, Leonie; Ramamoorthy, Anand; Konvalinka, Ivana

    2017-01-01

    in interpersonal coupling, the underlying brain mechanisms are not well understood. Here we argue that more general theories of neural computations, namely predictive coding and the Free Energy Principle, could explain interpersonal coordination dynamics. Each brain minimizes coding costs by reducing the mismatch...

  13. Alpha desynchronization/synchronization during working memory testing is compromised in acute mild traumatic brain injury (mTBI).

    Science.gov (United States)

    Arakaki, Xianghong; Shoga, Michael; Li, Lianyang; Zouridakis, George; Tran, Thao; Fonteh, Alfred N; Dawlaty, Jessica; Goldweber, Robert; Pogoda, Janice M; Harrington, Michael G

    2018-01-01

    Diagnosing and monitoring recovery of patients with mild traumatic brain injury (mTBI) is challenging because of the lack of objective, quantitative measures. Diagnosis is based on description of injuries often not witnessed, subtle neurocognitive symptoms, and neuropsychological testing. Since working memory (WM) is at the center of cognitive functions impaired in mTBI, this study was designed to define objective quantitative electroencephalographic (qEEG) measures of WM processing that may correlate with cognitive changes associated with acute mTBI. First-time mTBI patients and mild peripheral (limb) trauma controls without head injury were recruited from the emergency department. WM was assessed by a continuous performance task (N-back). EEG recordings were obtained during N-back testing on three occasions: within five days, two weeks, and one month after injury. Compared with controls, mTBI patients showed abnormal induced and evoked alpha activity including event-related desynchronization (ERD) and synchronization (ERS). For induced alpha power, TBI patients had excessive frontal ERD on their first and third visit. For evoked alpha, mTBI patients had lower parietal ERD/ERS at the second and third visits. These exploratory qEEG findings offer new and non-invasive candidate measures to characterize the evolution of injury over the first month, with potential to provide much-needed objective measures of brain dysfunction to diagnose and monitor the consequences of mTBI.

  14. Malignant Solitary Fibrous Tumor Metastatic to Widely Invasive Hurthle Cell Thyroid Carcinoma: A Distinct Tumor-to-Tumor Metastasis.

    Science.gov (United States)

    Kolson Kokohaare, Eva; Riva, Francesco M G; Bernstein, Jonathan M; Miah, Aisha B; Thway, Khin

    2018-04-01

    We illustrate a case of synchronous malignant solitary fibrous tumor of the thoracic cavity, and widely invasive thyroid Hurthle cell carcinoma. The Hurthle cell carcinoma was found to harbor distinct areas of malignant solitary fibrous tumor. This is a unique case of tumor-to-tumor metastasis that, to the best of our knowledge, has not been previously reported.

  15. NIRS-Based Hyperscanning Reveals Inter-brain Neural Synchronization during Cooperative Jenga Game with Face-to-Face Communication.

    Science.gov (United States)

    Liu, Ning; Mok, Charis; Witt, Emily E; Pradhan, Anjali H; Chen, Jingyuan E; Reiss, Allan L

    2016-01-01

    Functional near-infrared spectroscopy (fNIRS) is an increasingly popular technology for studying social cognition. In particular, fNIRS permits simultaneous measurement of hemodynamic activity in two or more individuals interacting in a naturalistic setting. Here, we used fNIRS hyperscanning to study social cognition and communication in human dyads engaged in cooperative and obstructive interaction while they played the game of Jenga™. Novel methods were developed to identify synchronized channels for each dyad and a structural node-based spatial registration approach was utilized for inter-dyad analyses. Strong inter-brain neural synchrony (INS) was observed in the posterior region of the right middle and superior frontal gyrus, in particular Brodmann area 8 (BA8), during cooperative and obstructive interaction. This synchrony was not observed during the parallel game play condition and the dialog section, suggesting that BA8 was involved in goal-oriented social interaction such as complex interactive movements and social decision-making. INS was also observed in the dorsomedial prefrontal cortex (dmPFC), in particular Brodmann 9, during cooperative interaction only. These additional findings suggest that BA9 may be particularly engaged when theory-of-mind (ToM) is required for cooperative social interaction. The new methods described here have the potential to significantly extend fNIRS applications to social cognitive research.

  16. Solitary magnetohydrodynamic vortices

    International Nuclear Information System (INIS)

    Silaev, I.I.; Skvortsov, A.T.

    1990-01-01

    This paper reports on the analytical description of fluid flow by means of localized vortices which is traditional for hydrodynamics, oceanology, plasma physics. Recently it has been widely applied to different structure turbulence models. Considerable results involved have been presented where it was shown that in magnetohydrodynamics alongside with the well-known kinds of localized vortices (e.g. Hill's vortex), which are characterized by quite a weak decrease of disturbed velocity or magnetic field (as a power of the inverse distance from vortex center), the vortices with screening (or solitary vortices) may exist. All disturbed parameters either exponentially vanish or become identically zero in outer region in the latter case. (In a number of papers numerical simulations of such the vortices are presented). Solutions in a form of solitary vortices are of particular interest due to their uniformity and solitonlike behavior. On the basis of these properties one can believe for such structures to occur in real turbulent flows

  17. MAP training: combining meditation and aerobic exercise reduces depression and rumination while enhancing synchronized brain activity.

    Science.gov (United States)

    Alderman, B L; Olson, R L; Brush, C J; Shors, T J

    2016-02-02

    Mental and physical (MAP) training is a novel clinical intervention that combines mental training through meditation and physical training through aerobic exercise. The intervention was translated from neuroscientific studies indicating that MAP training increases neurogenesis in the adult brain. Each session consisted of 30 min of focused-attention (FA) meditation and 30 min of moderate-intensity aerobic exercise. Fifty-two participants completed the 8-week intervention, which consisted of two sessions per week. Following the intervention, individuals with major depressive disorder (MDD; n=22) reported significantly less depressive symptoms and ruminative thoughts. Typical healthy individuals (n=30) also reported less depressive symptoms at follow-up. Behavioral and event-related potential indices of cognitive control were collected at baseline and follow-up during a modified flanker task. Following MAP training, N2 and P3 component amplitudes increased relative to baseline, especially among individuals with MDD. These data indicate enhanced neural responses during the detection and resolution of conflicting stimuli. Although previous research has supported the individual beneficial effects of aerobic exercise and meditation for depression, these findings indicate that a combination of the two may be particularly effective in increasing cognitive control processes and decreasing ruminative thought patterns.

  18. Solitary intraosseous neurofibroma of mandible.

    Directory of Open Access Journals (Sweden)

    Vivek N

    2006-01-01

    Full Text Available Solitary intraosseous neurofibroma is a rare benign non-odontogenic tumor. Although neurofibromas occur predominantly as a feature of neurofibromatosis affecting the soft tissue, a few cases of solitary intraosseous neurofibromas of the jaw have been reported. We herewith report a case of solitary intraosseous neurofibroma of mandible in a middle-aged woman with a discussion on its clinical, radiological, and histopathological presentation along with review of cases.

  19. Synchronous Oligometastatic Non-Small Cell Lung Cancer and Isolated Renal Cell Carcinoma: A Case Report and Literature Review.

    Science.gov (United States)

    Nguyen, Timothy K; Louie, Alexander V

    2015-10-27

    A 58-year-old gentleman presenting with a progressive headache, visual disturbance, decreased appetite, and weight loss was found to have a localized clear cell carcinoma of the kidney and synchronous Stage IV non-small cell lung cancer with a solitary brain metastasis. This case illustrates the challenges in distinguishing between primary and metastatic disease in a patient with both renal cell carcinoma and lung cancer. We highlight the uncertainties in the diagnosis and management of this unique clinical scenario and the potential implications on prognosis.

  20. Solitary eyelid schwannoma

    Directory of Open Access Journals (Sweden)

    Renu M Magdum

    2014-01-01

    Full Text Available Schwannomas are rare benign tumors arising from Schwann cells of peripheral nerves that form the neural sheath. While there have been reports of such tumors in the orbit, solitary schwannomas arising from the eyelids are very rare. There are reports of schwannomas being erroneously diagnosed as chalazion, inclusion cysts or even eyelid malignancy. We are reporting a case of a 20-year-old female who presented with a painless, non-tender, slow-growing mass in the upper eyelid of the right eye. The external appearance of the mass was suggestive of an implantation cyst of the eyelid and it could be completely excised as it had a well-defined capsule. Histopathological examination showed characteristic hypercellular and hypocellular areas with fusiform nuclei that tended to form palisades. The purpose of reporting this case of schwannoma in a young female is to recommend the inclusion of this entity as a differential diagnosis of well-defined lid tumors.

  1. On the time course of synchronization patterns of neuronal discharges in the human brain during cognitive tasks

    Czech Academy of Sciences Publication Activity Database

    Brázdil, M.; Janeček, Jiří; Klimeš, Petr; Mareček, R.; Roman, R.; Jurák, Pavel; Chládek, Jan; Daniel, P.; Rektor, I.; Halámek, Josef; Plešinger, Filip; Jirsa, V.

    2013-01-01

    Roč. 8, č. 5 (2013), e63293:1-9 E-ISSN 1932-6203 R&D Projects: GA ČR GAP103/11/0933; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : visual oddball task * working- memory * interareal synchronization * cortical areas Subject RIV: FH - Neurology Impact factor: 3.534, year: 2013

  2. Brief communication: Multiscaled solitary waves

    Science.gov (United States)

    Derzho, Oleg G.

    2017-11-01

    It is analytically shown how competing nonlinearities yield multiscaled structures for internal solitary waves in stratified shallow fluids. These solitary waves only exist for large amplitudes beyond the limit of applicability of the Korteweg-de Vries (KdV) equation or its usual extensions. The multiscaling phenomenon exists or does not exist for almost identical density profiles. The trapped core inside the wave prevents the appearance of such multiple scales within the core area. The structural stability of waves of large amplitudes is briefly discussed. Waves of large amplitudes displaying quadratic, cubic and higher-order nonlinear terms have stable and unstable branches. Multiscaled waves without a vortex core are shown to be structurally unstable. It is anticipated that multiscaling phenomena will exist for solitary waves in various physical contexts.

  3. Solitary eccrine syringofibroadenoma - Case Report*

    Science.gov (United States)

    Bottino, Caroline Bertolini; Guimarães, Tais Ferreira; Gomes, Flávio Rezende; D'Acri, Antonio Macedo; Lima, Ricardo Barbosa; Martins, Carlos José

    2015-01-01

    Eccrine syringofibroadenoma is a rare benign adnexal neoplasm derived from cells of the acrosyringium of eccrine sweat glands. ESFA usually manifests as a solitary nodule on the extremities of elderly patients, but it may also present as papules, nodules or plaques. Its clinical appearance is nonspecific and malignant neoplasms should beconsidered in the differential diagnosis. However, histopathological findings are typical. The main treatment is surgical excision. In order to illustrate a typical presentation of the tumor, we report a case of solitary eccrine syringofibroadenoma, including the surgical treatment used and its result. PMID:26312727

  4. Aging and body size in solitary bees

    Science.gov (United States)

    Solitary bees are important pollinators of crops and non-domestic plants. Osmia lignaria is a native, commercially-reared solitary bee used to maximize pollination in orchard crops. In solitary bees, adult body size is extremely variable depending on the nutritional resources available to the develo...

  5. Solitary waves and homoclinic orbits

    International Nuclear Information System (INIS)

    Balmforth, N.J.

    1994-03-01

    The notion that fluid motion often organizes itself into coherent structures has increasingly permeated modern fluid dynamics. Such localized objects appear in laminar flows and persist in turbulent states; from the water on windows on rainy days, to the circulations in planetary atmospheres. This review concerns solitary waves in fluids. More specifically, it centres around the mathematical description of solitary waves in a single spatial dimension. Moreover, it concentrates on strongly dissipative dynamics, rather than integrable systems like the KdV equation. One-dimensional solitary waves, or pulses and fronts as they are also called, are the simplest kinds of coherent structure (at least from a geometrical point of view). Nevertheless, their dynamics can be rich and complicated. In some circumstances this leads to the formation of spatio-temporal chaos in the systems giving birth to the solitary waves, and understanding that phenomenon is one of the major goals in the theory outlined in this review. Unfortunately, such a goal is far from achieved to date, and the author assess its current status and incompleteness

  6. Solitary waves and homoclinic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Balmforth, N.J.

    1994-03-01

    The notion that fluid motion often organizes itself into coherent structures has increasingly permeated modern fluid dynamics. Such localized objects appear in laminar flows and persist in turbulent states; from the water on windows on rainy days, to the circulations in planetary atmospheres. This review concerns solitary waves in fluids. More specifically, it centres around the mathematical description of solitary waves in a single spatial dimension. Moreover, it concentrates on strongly dissipative dynamics, rather than integrable systems like the KdV equation. One-dimensional solitary waves, or pulses and fronts as they are also called, are the simplest kinds of coherent structure (at least from a geometrical point of view). Nevertheless, their dynamics can be rich and complicated. In some circumstances this leads to the formation of spatio-temporal chaos in the systems giving birth to the solitary waves, and understanding that phenomenon is one of the major goals in the theory outlined in this review. Unfortunately, such a goal is far from achieved to date, and the author assess its current status and incompleteness.

  7. Solitary waves in particle beams

    International Nuclear Information System (INIS)

    Bisognano, J.J.

    1996-01-01

    Since space charge waves on a particle beam exhibit both dispersive and nonlinear character, solitary waves or solitons are possible. Dispersive, nonlinear wave propagation in high current beams is found to be similar to ion-acoustic waves in plasmas with an analogy between Debye screening and beam pipe shielding. Exact longitudinal solitary wave propagation is found for potentials associated with certain transverse distributions which fill the beam pipe. For weak dispersion, the waves satisfy the Korteweg-deVries (KdV) equation, but for strong dispersion they exhibit breaking. More physically realizable distributions which do not fill the beam pipe are investigated and shown to also satisfy a KdV equation for weak dispersion if averaging over rapid transverse motion is physically justified. Scaling laws are presented to explore likely parameter regimes where these phenomena may be observed experimentally

  8. Nonlinear positron acoustic solitary waves

    International Nuclear Information System (INIS)

    Tribeche, Mouloud; Aoutou, Kamel; Younsi, Smain; Amour, Rabia

    2009-01-01

    The problem of nonlinear positron acoustic solitary waves involving the dynamics of mobile cold positrons is addressed. A theoretical work is presented to show their existence and possible realization in a simple four-component plasma model. The results should be useful for the understanding of the localized structures that may occur in space and laboratory plasmas as new sources of cold positrons are now well developed.

  9. Epilepsy, electroacupuncture and the nucleus of the solitary tract.

    Science.gov (United States)

    Cakmak, Yusuf Ozgur

    2006-12-01

    Vagal nerve stimulation and electroacupuncture have some promise as neuroprotective therapies for patients with poorly controlled epilepsy. It has been demonstrated that stimulation of acupuncture points on the extremities results in stimulation of the vagus nerve. It is possible that the antiepileptic effects of these two applications might be targeting the same centre in the brain. The nucleus of the solitary tract, which is a primary site at which vagal afferents terminate, is also the site for afferent pathways of facial, scalp and auricular acupuncture via trigeminal, cervical spinal and glossopharyngeal nerves. Taken together with laboratory findings, the neuroprotective pathways of electroacupuncture in epileptic models may stem from the collaboration of its anti-inflammatory and neurotrophic actions through the nucleus of the solitary tract via vagus nerve stimulation.

  10. Solitary Intraosseous Neurofibroma of the Mandible

    Directory of Open Access Journals (Sweden)

    Hamideh Kadeh

    2014-07-01

    Full Text Available Neurofibroma is a benign neoplasm derived from peripheral nerve cells. Neurofibroma can occur as a solitary tumor also it may associate with neurofibromatosis. Intraosseous neurofibroma is a rare tumor particularly in the oral cavity. So far, few cases of solitary intraosseous neurofibroma of the mandible have been reported. In the present study, a 39 years old woman which has a diagnosis of solitary intraosseous neurofibroma of the mandible is reported. Clinical, radiographic, histopathologic and immunohistochemical features are described.

  11. Multi-component optical solitary waves

    DEFF Research Database (Denmark)

    Kivshar, Y. S.; Sukhorukov, A. A.; Ostrovskaya, E. A.

    2000-01-01

    We discuss several novel types of multi-component (temporal and spatial) envelope solitary waves that appear in fiber and waveguide nonlinear optics. In particular, we describe multi-channel solitary waves in bit-parallel-wavelength fiber transmission systems for highperformance computer networks......, multi-color parametric spatial solitary waves due to cascaded nonlinearities of quadratic materials, and quasiperiodic envelope solitons due to quasi-phase-matching in Fibonacci optical superlattices. (C) 2000 Elsevier Science B.V. All rights reserved....

  12. Synchronization, non-linear dynamics and low-frequency fluctuations: Analogy between spontaneous brain activity and networked single-transistor chaotic oscillators

    Science.gov (United States)

    Minati, Ludovico; Chiesa, Pietro; Tabarelli, Davide; D'Incerti, Ludovico; Jovicich, Jorge

    2015-03-01

    In this paper, the topographical relationship between functional connectivity (intended as inter-regional synchronization), spectral and non-linear dynamical properties across cortical areas of the healthy human brain is considered. Based upon functional MRI acquisitions of spontaneous activity during wakeful idleness, node degree maps are determined by thresholding the temporal correlation coefficient among all voxel pairs. In addition, for individual voxel time-series, the relative amplitude of low-frequency fluctuations and the correlation dimension (D2), determined with respect to Fourier amplitude and value distribution matched surrogate data, are measured. Across cortical areas, high node degree is associated with a shift towards lower frequency activity and, compared to surrogate data, clearer saturation to a lower correlation dimension, suggesting presence of non-linear structure. An attempt to recapitulate this relationship in a network of single-transistor oscillators is made, based on a diffusive ring (n = 90) with added long-distance links defining four extended hub regions. Similarly to the brain data, it is found that oscillators in the hub regions generate signals with larger low-frequency cycle amplitude fluctuations and clearer saturation to a lower correlation dimension compared to surrogates. The effect emerges more markedly close to criticality. The homology observed between the two systems despite profound differences in scale, coupling mechanism and dynamics appears noteworthy. These experimental results motivate further investigation into the heterogeneity of cortical non-linear dynamics in relation to connectivity and underline the ability for small networks of single-transistor oscillators to recreate collective phenomena arising in much more complex biological systems, potentially representing a future platform for modelling disease-related changes.

  13. Synchronization, non-linear dynamics and low-frequency fluctuations: Analogy between spontaneous brain activity and networked single-transistor chaotic oscillators

    International Nuclear Information System (INIS)

    Minati, Ludovico; Chiesa, Pietro; Tabarelli, Davide; Jovicich, Jorge; D'Incerti, Ludovico

    2015-01-01

    In this paper, the topographical relationship between functional connectivity (intended as inter-regional synchronization), spectral and non-linear dynamical properties across cortical areas of the healthy human brain is considered. Based upon functional MRI acquisitions of spontaneous activity during wakeful idleness, node degree maps are determined by thresholding the temporal correlation coefficient among all voxel pairs. In addition, for individual voxel time-series, the relative amplitude of low-frequency fluctuations and the correlation dimension (D 2 ), determined with respect to Fourier amplitude and value distribution matched surrogate data, are measured. Across cortical areas, high node degree is associated with a shift towards lower frequency activity and, compared to surrogate data, clearer saturation to a lower correlation dimension, suggesting presence of non-linear structure. An attempt to recapitulate this relationship in a network of single-transistor oscillators is made, based on a diffusive ring (n = 90) with added long-distance links defining four extended hub regions. Similarly to the brain data, it is found that oscillators in the hub regions generate signals with larger low-frequency cycle amplitude fluctuations and clearer saturation to a lower correlation dimension compared to surrogates. The effect emerges more markedly close to criticality. The homology observed between the two systems despite profound differences in scale, coupling mechanism and dynamics appears noteworthy. These experimental results motivate further investigation into the heterogeneity of cortical non-linear dynamics in relation to connectivity and underline the ability for small networks of single-transistor oscillators to recreate collective phenomena arising in much more complex biological systems, potentially representing a future platform for modelling disease-related changes

  14. Synchronous changes of cortical thickness and corresponding white matter microstructure during brain development accessed by diffusion MRI tractography from parcellated cortex

    Directory of Open Access Journals (Sweden)

    Tina eJeon

    2015-12-01

    Full Text Available Cortical thickness (CT changes during normal brain development is associated with complicated cellular and molecular processes including synaptic pruning and apoptosis. In parallel, the microstructural enhancement of developmental white matter (WM axons with their neuronal bodies in the cerebral cortex has been widely reported with measurements of metrics derived from diffusion tensor imaging (DTI, especially fractional anisotropy (FA. We hypothesized that the changes of CT and microstructural enhancement of corresponding axons are highly interacted during development. DTI and T1-weighted images of 50 healthy children and adolescents between the ages of 7 to 25 years were acquired. With the parcellated cortical gyri transformed from T1-weighted images to DTI space as the tractography seeds, probabilistic tracking was performed to delineate the WM fibers traced from specific parcellated cortical regions. CT was measured at certain cortical regions and FA was measured from the WM fibers traced from same cortical regions. The CT of all frontal cortical gyri, includeing Brodmann areas 4, 6, 8, 9, 10, 11, 44, 45, 46 and 47, decreased significantly and heterogeneously; concurrently, significant and heterogeneous increases of FA of WM traced from corresponding regions were found. We further revealed significant correlation between the slopes of the CT decrease and the slopes of corresponding WM FA increase in all frontal cortical gyri, suggesting coherent cortical pruning and corresponding WM microstructural enhancement. Such correlation was not found in cortical regions other than frontal cortex. The molecular and cellular mechanisms of these synchronous changes may be associated with overlapping signaling pathways of axonal guidance, synaptic pruning, neuronal apoptosis and more prevalent interstitial neurons in the prefrontal cortex. Revealing the coherence of cortical and WM structural changes during development may open a new window for

  15. Long-term survival in patients with non-small cell lung cancer and synchronous brain metastasis treated with whole-brain radiotherapy and thoracic chemoradiation

    International Nuclear Information System (INIS)

    Arrieta, Oscar; Villarreal-Garza, Cynthia; Zamora, Jesús; Blake-Cerda, Mónika; Mata, María D de la; Zavala, Diego G; Muñiz-Hernández, Saé; Garza, Jaime de la

    2011-01-01

    Brain metastases occur in 30-50% of Non-small cell lung cancer (NSCLC) patients and confer a worse prognosis and quality of life. These patients are usually treated with Whole-brain radiotherapy (WBRT) followed by systemic therapy. Few studies have evaluated the role of chemoradiotherapy to the primary tumor after WBRT as definitive treatment in the management of these patients. We reviewed the outcome of 30 patients with primary NSCLC and brain metastasis at diagnosis without evidence of other metastatic sites. Patients were treated with WBRT and after induction chemotherapy with paclitaxel and cisplatin for two cycles. In the absence of progression, concurrent chemoradiotherapy for the primary tumor with weekly paclitaxel and carboplatin was indicated, with a total effective dose of 60 Gy. If disease progression was ruled out, four chemotherapy cycles followed. Median Progression-free survival (PFS) and Overall survival (OS) were 8.43 ± 1.5 and 31.8 ± 15.8 months, respectively. PFS was 39.5% at 1 year and 24.7% at 2 years. The 1- and 2-year OS rates were 71.1 and 60.2%, respectively. Three-year OS was significantly superior for patients with N0-N1 stage disease vs. N2-N3 (60 vs. 24%, respectively; Response rate [RR], 0.03; p= 0.038). Patients with NSCLC and brain metastasis might benefit from treatment with WBRT and concurrent thoracic chemoradiotherapy. The subgroup of N0-N1 patients appears to achieve the greatest benefit. The result of this study warrants a prospective trial to confirm the benefit of this treatment

  16. Solitary odontodysplasia: A rare entity

    Directory of Open Access Journals (Sweden)

    D Gurunathan

    2011-01-01

    Full Text Available Odontodysplasia is a rare, non-hereditary developmental anomaly affecting dental tissues derived from both the mesoderm and ectoderm which results in a bizarre clinical and radiographic appearance. Regional odontodysplasia describes the segmental and localized nature of the condition. Odontodysplasia occurring in a single tooth is a rare occurrence. A case of Solitary odontodysplasia in an eleven year and half old male whose chief complaint was the absence of eruption of permanent maxillary right central incisor teeth is presented. Clinical, radiographic and histological findings of a single tooth, odontodysplasia are described in this case report.

  17. Management of a solitary thyroid nodule

    International Nuclear Information System (INIS)

    Rao, R.S.

    1999-01-01

    Solitary nodule in the thyroid is a common clinical entity. A careful clinical assessment is the crucial first step in deciding the modality of treatment. The only worthwhile investigation is FNAC. Other investigations are done merely for the sake of a complete academic work up and can usually be dispensed with in most of the cases. Not every solitary nodule requires surgery. The optimum surgery for a solitary nodule is a total lobectomy. The specimen should be subjected to histological examination before recommending further treatment

  18. Solitary Fibrous Tumor of the Uterus

    Directory of Open Access Journals (Sweden)

    Po-Wei Chu

    2006-12-01

    Conclusion: The behavior of solitary fibrous tumors arising from the uterus is difficult to evaluate; therefore, complete surgical excision featuring clear margins and comprehensive follow-up is recommended.

  19. The cytology of giant solitary trichoepithelioma

    Directory of Open Access Journals (Sweden)

    Krishnamurthy Jayashree

    2010-01-01

    Full Text Available Giant solitary trichoepithelioma (GST is a rare trichogenic tumor, which may present as a pigmented lesion. An 80-year-old man was diagnosed to have giant solitary trichoepithelioma on fine-needle aspiration cytology. The cytological findings represented the histological features. The recognition of GST is important because of its close resemblance to basal cell carcinoma and other skin adnexal tumors - clinically, cytologically and histologically.

  20. Solitary sternal lesions in breast cancer

    International Nuclear Information System (INIS)

    Morales, R.; Cano, R.; Mendoza, G.; Guzman, C.; Cotrina, M.; Aguilar, C.

    1993-01-01

    In a retrospective review of bone scans performed in 1740 patients with breast cancer from January 1988 to April 1993, twenty had a solitary sternal lesion. Etiology was found correlating this finding with pathology, x-rays and/or final outcome. Nineteen lesions were due to metastases and one to infection. This experience suggests that solitary sternal lesions in breast cancer patients are uncommon and are most frequently (95%) associated with malignant etiology. (Authors). 10 refs., 2 figs

  1. Social modulation of the daily activity rhythm in a solitary subterranean rodent, the tuco-tuco (Ctenomys sp) : SI: Chronobiology in Latin America

    NARCIS (Netherlands)

    Tomotani, Barbara Mizumo; Amaya, Juan Pablo; Oda, Gisele Akemi; Valentinuzzi, Veronica Sandra

    2016-01-01

    Abstract South American subterranean rodents are mainly described as solitary and mutual synchronization was never observed among individuals maintained together in laboratory. We report that a single birth event was capable of disrupting the robust nocturnal activity rhythm of singly housed

  2. Solitary wave propagation in solar flux tubes

    International Nuclear Information System (INIS)

    Erdelyi, Robert; Fedun, Viktor

    2006-01-01

    The aim of the present work is to investigate the excitation, time-dependent dynamic evolution, and interaction of nonlinear propagating (i.e., solitary) waves on vertical cylindrical magnetic flux tubes in compressible solar atmospheric plasma. The axisymmetric flux tube has a field strength of 1000 G at its footpoint, which is typical for photospheric regions. Nonlinear waves that develop into solitary waves are excited by a footpoint driver. The propagation of the nonlinear signal is investigated by solving numerically a set of fully nonlinear 2.0D magnetohydrodynamic (MHD) equations in cylindrical coordinates. For the initial conditions, axisymmetric solutions of the linear dispersion relation for wave modes in a magnetic flux tube are applied. In the present case, we focus on the sausage mode only. The dispersion relation is solved numerically for a range of plasma parameters. The equilibrium state is perturbed by a Gaussian at the flux tube footpoint. Two solitary solutions are found by solving the full nonlinear MHD equations. First, the nonlinear wave propagation with external sound speed is investigated. Next, the solitary wave propagating close to the tube speed, also found in the numerical solution, is studied. In contrast to previous analytical and numerical works, here no approximations were made to find the solitary solutions. A natural application of the present study may be spicule formation in the low chromosphere. Future possible improvements in modeling and the relevance of the photospheric chromospheric transition region coupling by spicules is suggested

  3. Solitary restriction endonucleases in prokaryotic genomes.

    Science.gov (United States)

    Ershova, Anna S; Karyagina, Anna S; Vasiliev, Mikhail O; Lyashchuk, Alexander M; Lunin, Vladimir G; Spirin, Sergey A; Alexeevski, Andrei V

    2012-11-01

    Prokaryotic restriction-modification (R-M) systems defend the host cell from the invasion of a foreign DNA. They comprise two enzymatic activities: specific DNA cleavage activity and DNA methylation activity preventing cleavage. Typically, these activities are provided by two separate enzymes: a DNA methyltransferase (MTase) and a restriction endonuclease (RE). In the absence of a corresponding MTase, an RE of Type II R-M system is highly toxic for the cell. Genes of the R-M system are linked in the genome in the vast majority of annotated cases. There are only a few reported cases in which the genes of MTase and RE from one R-M system are not linked. Nevertheless, a few hundreds solitary RE genes are present in the Restriction Enzyme Database (http://rebase.neb.com) annotations. Using the comparative genomic approach, we analysed 272 solitary RE genes. For 57 solitary RE genes we predicted corresponding MTase genes located distantly in a genome. Of the 272 solitary RE genes, 99 are likely to be fragments of RE genes. Various explanations for the existence of the remaining 116 solitary RE genes are also discussed.

  4. Convergence of cranial visceral afferents within the solitary tract nucleus.

    Science.gov (United States)

    McDougall, Stuart J; Peters, James H; Andresen, Michael C

    2009-10-14

    Primary afferent axons within the solitary tract (ST) relay homeostatic information via glutamatergic synapses directly to second-order neurons within the nucleus of the solitary tract (NTS). These primary afferents arise from multiple organ systems and relay multiple sensory modalities. How this compact network organizes the flow of primary afferent information will shape central homeostatic control. To assess afferent convergence and divergence, we recorded ST-evoked synaptic responses in pairs of medial NTS neurons in horizontal brainstem slices. ST shocks activated EPSCs along monosynaptic or polysynaptic pathways. Gradations in shock intensity discriminated multiple inputs and stimulus recruitment profiles indicated that each EPSC was unitary. In 24 pairs, 75% were second-order neurons with 64% receiving one direct ST input with the remainder receiving additional convergent ST afferent inputs (22% two; 14% three monosynaptic ST-EPSCs). Some (34%) second-order neurons received polysynaptic EPSCs. Neurons receiving only higher-order inputs were uncommon (13%). Most ST-EPSCs were completely independent, but 4 EPSCs of a total of 81 had equal thresholds, highly correlated latencies, and synchronized synaptic failures consistent with divergence from a single source ST axon or from a common interneuron producing a pair of polysynaptic EPSCs. We conclude that ST afferent inputs are remarkably independent with little evidence of substantial shared information. Individual cells receive highly focused information from the viscera. Thus, afferent excitation of second-order NTS neurons is generally dominated by single visceral afferents and therefore focused on a single afferent modality and/or organ region.

  5. Cervical vagus nerve stimulation augments spontaneous discharge in second- and higher-order sensory neurons in the rat nucleus of the solitary tract.

    Science.gov (United States)

    Beaumont, Eric; Campbell, Regenia P; Andresen, Michael C; Scofield, Stephanie; Singh, Krishna; Libbus, Imad; KenKnight, Bruce H; Snyder, Logan; Cantrell, Nathan

    2017-08-01

    Vagus nerve stimulation (VNS) currently treats patients with drug-resistant epilepsy, depression, and heart failure. The mild intensities used in chronic VNS suggest that primary visceral afferents and central nervous system activation are involved. Here, we measured the activity of neurons in the nucleus of the solitary tract (NTS) in anesthetized rats using clinically styled VNS. Our chief findings indicate that VNS at threshold bradycardic intensity activated NTS neuron discharge in one-third of NTS neurons. This VNS directly activated only myelinated vagal afferents projecting to second-order NTS neurons. Most VNS-induced activity in NTS, however, was unsynchronized to vagal stimuli. Thus, VNS activated unsynchronized activity in NTS neurons that were second order to vagal afferent C-fibers as well as higher-order NTS neurons only polysynaptically activated by the vagus. Overall, cardiovascular-sensitive and -insensitive NTS neurons were similarly activated by VNS: 3/4 neurons with monosynaptic vagal A-fiber afferents, 6/42 neurons with monosynaptic vagal C-fiber afferents, and 16/21 polysynaptic NTS neurons. Provocatively, vagal A-fibers indirectly activated C-fiber neurons during VNS. Elevated spontaneous spiking was quantitatively much higher than synchronized activity and extended well into the periods of nonstimulation. Surprisingly, many polysynaptic NTS neurons responded to half the bradycardic intensity used in clinical studies, indicating that a subset of myelinated vagal afferents is sufficient to evoke VNS indirect activation. Our study uncovered a myelinated vagal afferent drive that indirectly activates NTS neurons and thus central pathways beyond NTS and support reconsideration of brain contributions of vagal afferents underpinning of therapeutic impacts. NEW & NOTEWORTHY Acute vagus nerve stimulation elevated activity in neurons located in the medial nucleus of the solitary tract. Such stimuli directly activated only myelinated vagal afferents

  6. Total ureterectomy and ileal ureteric replacement for TCC ureter in a solitary kidney.

    Science.gov (United States)

    Banerji, John S; George, Arun J P

    2014-11-01

    Traditional treatment of upper tract transitional cell carcinoma (TCC) is nephroureterectomy with a bladder cuff. This is in keeping with the nature of the disease, in that TCC is a panurothelial disease. However, there are a few rare occasions when this would mean making a subject anephric, as in a TCC in a solitary kidney or bilateral synchronous/metachronous disease. We present a case of a patient with a dysplastic, poorly functioning left kidney and with a TCC of the ureter on the right side.

  7. Solitary waves in dimer binary collision model

    Science.gov (United States)

    Ahsan, Zaid; Jayaprakash, K. R.

    2017-01-01

    Solitary wave propagation in nonlinear diatomic (dimer) chains is a very interesting topic of research in the study of nonlinear lattices. Such waves were recently found to be supported by the essentially nonlinear granular lattice and Toda lattice. An interesting aspect of this discovery is attributed to the realization of a spectrum of the mass ratio (the only system parameter governing the dynamics) that supports the propagation of such waves corresponding to the considered interaction potential. The objective of this exposition is to explore solitary wave propagation in the dimer binary collision (BC) model. Interestingly, the dimer BC model supports solitary wave propagation at a discrete spectrum of mass ratios similar to those observed in granular and Toda dimers. Further, we report a qualitative and one-to-one correspondence between the spectrum of the mass ratio corresponding to the dimer BC model and those corresponding to granular and Toda dimer chains.

  8. Solitary neurofibroma of eyelid masquerading as chalazion.

    Science.gov (United States)

    Chen, Nancy; Hsu, Yung-Hsiang; Lee, Yuan-Chieh

    2017-01-01

    Neurofibroma, a benign peripheral nerve sheath tumor, usually appears together with café-au-lait spots, iris nodules, and other tumors within the scope of neurofibromatosis von Recklinghausen type 1 tumors. A solitary neurofibroma of the eyelid is relatively rare. In this case report, we present a 39-year-old woman who had a lesion on the eyelid crease, previously treated as a chalazion. Due to persistent wound crusting, the lesion was excised above the tarsus. Pathological examination revealed a solitary neurofibroma. The patient did not have other clinical symptoms of neurofibromatosis, and there was no recurrence of the nodule during the 1-year follow-up.

  9. Solitary gastric melanotic schwannoma: sonographic findings.

    Science.gov (United States)

    Chen, Yang-Yuan; Yen, Hsu-Heng; Soon, Maw-Soan

    2007-01-01

    Solitary gastric schwannoma is rare, and solitary melanotic schwannoma is even rarer, posing a dilemma in diagnosis and treatment. We report the case of a 69-year-old woman with gastric melanotic schwannoma who presented with nausea, vomiting, and abdominal pain. Abdominal sonographic examination revealed a 5-cm hypoechoic mass in the epigastric area that was confirmed to be a gastric submucosal tumor on endoscopic examination. The diagnosis of melanotic schwannoma was confirmed via sonographically guided percutaneous core biopsy. The tumor was resected, and no recurrence has occurred in a 3-year follow-up.

  10. Solitary extramedullary plasmacytoma of the sinonasal region.

    Science.gov (United States)

    Hazarika, Produl; Balakrishnan, R; Singh, Rohit; Pujary, Kailesh; Aziz, Benazim

    2011-07-01

    Less than 10% of the patients with plasma cell neoplasms present with a solitary plasmacytoma. Though the nasal cavity is a common extramedullary site, the occurrence is extremely rare. Two cases of solitary extramedullary plasmacytoma of the sinonasal region are reported. The first of which is sinonasal plasmacytoma with concomitant HIV, an association that has been reported rarely in literature to date and is matter of much debate. In the second case report, we present an instance of surgical excision of the tumor using KTP 532 laser. The diagnosis was established using immunohistochemical techniques and multiple myeloma workups were negative in all cases.

  11. Solitary eccrine syringofibroadenoma--Case Report.

    Science.gov (United States)

    Bottino, Caroline Bertolini; Guimarães, Tais Ferreira; Gomes, Flávio Rezende; D'Acri, Antonio Macedo; Lima, Ricardo Barbosa; Martins, Carlos José

    2015-01-01

    Eccrine syringofibroadenoma is a rare benign adnexal neoplasm derived from cells of the acrosyringium of eccrine sweat glands. ESFA usually manifests as a solitary nodule on the extremities of elderly patients, but it may also present as papules, nodules or plaques. Its clinical appearance is nonspecific and malignant neoplasms should be considered in the differential diagnosis. However, histopathological findings are typical. The main treatment is surgical excision. In order to illustrate a typical presentation of the tumor, we report a case of solitary eccrine syringofibroadenoma, including the surgical treatment used and its result.

  12. Formation and Coalescence of Electron Solitary Holes

    DEFF Research Database (Denmark)

    Saeki, K.; Michelsen, Poul; Pécseli, H. L.

    1979-01-01

    Electron solitary holes were observed in a magnetized collisionless plasma. These holes were identified as Bernstein-Green-Kruskal equilibria, thus being purely kinetic phenomena. The electron hole does not damp even though its velocity is close to the electron thermal velocity. Two holes attract...

  13. Electrophysiological effects of the solitary bee "Anthophora

    African Journals Online (AJOL)

    Department of Zoology, Faculty of Science, Suez Canal University, Ismailia, Egypt. ABSTRACT. Effects of the crude venom of the solitary bee (Anthophora pauperata) on cardiac, skeletal and smooth muscles were studied to reveal the mechanism of action of this venom. The main toxic effects on the ECG of isolated toads'.

  14. Peptide Toxins in Solitary Wasp Venoms

    Directory of Open Access Journals (Sweden)

    Katsuhiro Konno

    2016-04-01

    Full Text Available Solitary wasps paralyze insects or spiders with stinging venom and feed the paralyzed preys to their larva. Accordingly, the venoms should contain a variety of constituents acting on nervous systems. However, only a few solitary wasp venoms have been chemically studied despite thousands of species inhabiting the planet. We have surveyed bioactive substances in solitary wasp venoms found in Japan and discovered a variety of novel bioactive peptides. Pompilidotoxins (PMTXs, in the venoms of the pompilid wasps Anoplius samariensis and Batozonellus maculifrons, are small peptides consisting of 13 amino acids without a disulfide bond. PMTXs slowed Na+ channel inactivation, in particular against neuronal type Na+ channels, and were rather selective to the Nav1.6 channel. Mastoparan-like cytolytic and antimicrobial peptides are the major components of eumenine wasp venoms. They are rich in hydrophobic and basic amino acids, adopting a α-helical secondary structure, and showing mast cell degranulating, antimicrobial and hemolytic activities. The venom of the spider wasp Cyphononyx fulvognathus contained four bradykinin-related peptides. They are hyperalgesic and, dependent on the structure, differently associated with B1 or B2 receptors. Further survey led to the isolation of leucomyosuppressin-like FMRFamide peptides from the venoms of the digger wasps Sphex argentatus and Isodontia harmandi. These results of peptide toxins in solitary wasp venoms from our studies are summarized.

  15. Surf similarity and solitary wave runup

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Madsen, Per A.

    2008-01-01

    to a previous parameterization, which was not given in an explicit form. Good coherency with experimental (breaking) runup data is preserved with this simpler parameter. A recasting of analytical (nonbreaking) runup expressions for sinusoidal and solitary waves additionally shows that they contain identical...

  16. CFD Analysis of Water Solitary Wave Reflection

    Directory of Open Access Journals (Sweden)

    K. Smida

    2011-12-01

    Full Text Available A new numerical wave generation method is used to investigate the head-on collision of two solitary waves. The reflection at vertical wall of a solitary wave is also presented. The originality of this model, based on the Navier-Stokes equations, is the specification of an internal inlet velocity, defined as a source line within the computational domain for the generation of these non linear waves. This model was successfully implemented in the PHOENICS (Parabolic Hyperbolic Or Elliptic Numerical Integration Code Series code. The collision of two counter-propagating solitary waves is similar to the interaction of a soliton with a vertical wall. This wave generation method allows the saving of considerable time for this collision process since the counter-propagating wave is generated directly without reflection at vertical wall. For the collision of two solitary waves, numerical results show that the run-up phenomenon can be well explained, the solution of the maximum wave run-up is almost equal to experimental measurement. The simulated wave profiles during the collision are in good agreement with experimental results. For the reflection at vertical wall, the spatial profiles of the wave at fixed instants show that this problem is equivalent to the collision process.

  17. Histoplasmosis presenting with solitary pulmonary nodule: Two ...

    African Journals Online (AJOL)

    Pulmonary histoplasmosis is a granulomatous disease, whose diagnosis is not always easy, as it may simulate metastatic lesions due to similar radiographic findings. We herein report two cases of histoplasmosis with solitary pulmonary nodule in asymptomatic patients with histories of cancer surgeries, whose diagnoses ...

  18. Position of solitary thyroid nodules by gammagraphy

    International Nuclear Information System (INIS)

    Basteris M, J.; Gomez D, R.

    2007-01-01

    In this work it is presented which it is the position more frequent of the solitary thyroid nodules. It was used the method of retrospective longitudinal observational investigation in 125 patients that went to the laboratory for realization of detection of thyroid nodules in the years 2004 and 2005 through gammagraphy. (Author)

  19. Solitary waves on nonlinear elastic rods. I

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.

    1984-01-01

    Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the elastic medium are taken into account. Solitary wave solutions to these equations have been found. The present paper treats the interaction between...

  20. Solitary waves on nonlinear elastic rods. II

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.

    1987-01-01

    In continuation of an earlier study of propagation of solitary waves on nonlinear elastic rods, numerical investigations of blowup, reflection, and fission at continuous and discontinuous variation of the cross section for the rod and reflection at the end of the rod are presented. The results...

  1. Is percutaneous nephrolithotomy in solitary kidneys safe?

    Science.gov (United States)

    Wong, Kathie Alexina; Sahai, Arun; Patel, Amit; Thomas, Kay; Bultitude, Matthew; Glass, Jonathan

    2013-11-01

    To review our experience from a high volume stone center with a focus on efficacy, safety, and renal function. Stones requiring percutaneous nephrolithotomy (PCNL) in patients with solitary kidneys can pose significant anxiety to the urologist. Limited data are available in published reports in this setting. A comprehensive retrospective review of medical records was performed on patients who underwent PCNL and had a solitary kidney or a single functioning renal unit. Data were collected on patient demographics, stone burden, outcomes, complications, and renal function. Of 378 PCNLs performed between January 2003 and September 2011, 22 were performed in 17 patients with a single functioning kidney. Three procedures were performed in a transplanted kidney. In those with solitary calculus, the longest mean length and stone surface area were 37 mm and 825 mm(2), respectively. Stone-free rate was 59%. Auxiliary procedures were required in 6 cases, resulting in a stone-free rate of 77%. Median inpatient stay was 4 days. Serum creatinine values improved from 144 to 126 umol/L before and after the procedure and mean estimated glomerular filtration rate improved similarly from 51 to 59 mls/minute, respectively. Blood transfusion was required in 1 patient, sepsis developed in 3, and 2 patients required a stent for obstruction. PCNL in solitary kidneys is safe with an acceptable complication rate if performed in a high volume center. Outcomes are good, although auxiliary procedures may be necessary. Renal function remains stable or improves after procedure. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Clinical implications of the solitary functioning kidney

    NARCIS (Netherlands)

    Westland, Rik; Schreuder, Michiel F.; van Goudoever, Johannes B.; Sanna-Cherchi, Simone; van Wijk, Joanna A. E.

    2014-01-01

    Congenital anomalies of the kidney and urinary tract are the major cause of ESRD in childhood. Children with a solitary functioning kidney form an important subgroup of congenital anomalies of the kidney and urinary tract patients, and a significant fraction of these children is at risk for

  3. The solitary sellar plasmacytoma: a diagnostic challenge

    DEFF Research Database (Denmark)

    Soejbjerg, Anne; Dyve, Suzan; Baerentzen, Steen

    2016-01-01

    UNLABELLED: Solitary sellar plasmacytomas are exceedingly rare and difficult to distinguish from other pituitary tumors. We report a case of a 62-year-old woman presenting with blurred vision of the right eye and tenderness of the right temporal region, which was interpreted as temporal arteritis...

  4. Cluster Synchronization Algorithms

    NARCIS (Netherlands)

    Xia, Weiguo; Cao, Ming

    2010-01-01

    This paper presents two approaches to achieving cluster synchronization in dynamical multi-agent systems. In contrast to the widely studied synchronization behavior, where all the coupled agents converge to the same value asymptotically, in the cluster synchronization problem studied in this paper,

  5. Synchronization of chaotic systems

    International Nuclear Information System (INIS)

    Pecora, Louis M.; Carroll, Thomas L.

    2015-01-01

    We review some of the history and early work in the area of synchronization in chaotic systems. We start with our own discovery of the phenomenon, but go on to establish the historical timeline of this topic back to the earliest known paper. The topic of synchronization of chaotic systems has always been intriguing, since chaotic systems are known to resist synchronization because of their positive Lyapunov exponents. The convergence of the two systems to identical trajectories is a surprise. We show how people originally thought about this process and how the concept of synchronization changed over the years to a more geometric view using synchronization manifolds. We also show that building synchronizing systems leads naturally to engineering more complex systems whose constituents are chaotic, but which can be tuned to output various chaotic signals. We finally end up at a topic that is still in very active exploration today and that is synchronization of dynamical systems in networks of oscillators

  6. Partial Differential Equations and Solitary Waves Theory

    CERN Document Server

    Wazwaz, Abdul-Majid

    2009-01-01

    "Partial Differential Equations and Solitary Waves Theory" is a self-contained book divided into two parts: Part I is a coherent survey bringing together newly developed methods for solving PDEs. While some traditional techniques are presented, this part does not require thorough understanding of abstract theories or compact concepts. Well-selected worked examples and exercises shall guide the reader through the text. Part II provides an extensive exposition of the solitary waves theory. This part handles nonlinear evolution equations by methods such as Hirota’s bilinear method or the tanh-coth method. A self-contained treatment is presented to discuss complete integrability of a wide class of nonlinear equations. This part presents in an accessible manner a systematic presentation of solitons, multi-soliton solutions, kinks, peakons, cuspons, and compactons. While the whole book can be used as a text for advanced undergraduate and graduate students in applied mathematics, physics and engineering, Part II w...

  7. On the solitary wave paradigm for tsunamis

    DEFF Research Database (Denmark)

    Madsen, Per A.; Fuhrman, David R.; Schäffer, Hemming Andreas

    2008-01-01

    Since the 1970s, solitary waves have commonly been used to model tsunamis especially in experimental and mathematical studies. Unfortunately, the link to geophysical scales is not well established, and in this work we question the geophysical relevance of this paradigm. In part 1, we simulate...... of finite amplitude solitary wave theory in laboratory studies of tsunamis. We conclude that order-of-magnitude errors in effective temporal and spatial duration occur when this theory is used as an approximation for long waves on a sloping bottom. In part 3, we investigate the phenomenon of disintegration...... of long waves into shorter waves, which has been observed e.g. in connection with the Indian Ocean tsunami in 2004. This happens if the front of the tsunami becomes sufficently steep, and as a result the front turns into an undular bore. We discuss the importance of these very short waves in connection...

  8. A large solitary liver metastasis of thymoma

    International Nuclear Information System (INIS)

    Kang, Si Won; Shinn, Kyung Sub

    1997-01-01

    Extrathoracic metastasis of a thymoma is rare ; we report a case of metastasis to the liver of a large solitary thymoma. Biopsy of the mass showed it to be predominantly lymphocytic and histologically the same as a primary thymoma operated on four years previously. On ultrasound and CT scan, the majority of the metastatic tumor was hemorrhagic, necrotic and/or cystic, with a peripheral, irregularly thick solid component and rather thin, smooth encapsulation

  9. A large solitary liver metastasis of thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Si Won; Shinn, Kyung Sub [Catholic Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-01-01

    Extrathoracic metastasis of a thymoma is rare ; we report a case of metastasis to the liver of a large solitary thymoma. Biopsy of the mass showed it to be predominantly lymphocytic and histologically the same as a primary thymoma operated on four years previously. On ultrasound and CT scan, the majority of the metastatic tumor was hemorrhagic, necrotic and/or cystic, with a peripheral, irregularly thick solid component and rather thin, smooth encapsulation.

  10. Event–Related Synchronization/Desynchronization in Coupled ...

    Indian Academy of Sciences (India)

    V. K. Chandrasekar

    ERS ERD/ERS in an array of coupled Stuart-Landau oscill. Aim . Aim . . To present a general coupled nonlinear oscillator model for event-related synchronization/desynchronization (ESR/ERD). To explain relevant experiment in brain dynamics.

  11. Role of reticular activation in the modulation of intracortical synchronization

    NARCIS (Netherlands)

    Munk, M. H.; Roelfsema, P. R.; König, P.; Engel, A. K.; Singer, W.

    1996-01-01

    During aroused states of the brain, electroencephalographic activity is characterized by fast, irregular fluctuations of low amplitude, which are thought to reflect desynchronization of neuronal activity. This phenomenon seems at odds with the proposal that synchronization of cortical responses may

  12. Estimate of the degree of synchronization in the intermittent phase synchronization regime from a time series (model systems and neurophysiological data)

    Science.gov (United States)

    Moskalenko, O. I.; Koronovskii, A. A.; Hramov, A. E.; Zhuravlev, M. O.

    2016-04-01

    A method for determining the degree of synchronization of intermittent phase synchronization regime from a time series has been proposed on the basis of estimating the zero conditional Lyapunov exponent. The efficiency of the method has been tested on model systems near the boundary of the appearance of the synchronous regime. The method has been used to determine the degree of synchronization between various regions of the brain of rats of the WAG/Rij line having a genetic predisposition to epilepsy.

  13. Malignant solitary fibrous tumor metastatic to the orbit.

    Science.gov (United States)

    Glazer-Hockstein, Carolyn; Syed, Nasreen A; Warhol, Michael; Gausas, Roberta E

    2004-11-01

    A 61-year-old man with a history of malignant solitary fibrous tumor of the chest had development of unusual sites of metastasis involving the sphenoid wing of the orbit and soft tissues of the cheek. He was found to have a solitary fibrous tumor, an uncommon type of spindle cell neoplasm that most often arises in the pleura, which was metastatic to the orbit. This is the first reported case of malignant solitary fibrous tumor metastatic to the orbit. The clinical and histopathologic findings of metastatic malignant solitary fibrous tumor are described.

  14. The cruel and unusual phenomenology of solitary confinement.

    Science.gov (United States)

    Gallagher, Shaun

    2014-01-01

    What happens when subjects are deprived of intersubjective contact? This paper looks closely at the phenomenology and psychology of one example of that deprivation: solitary confinement. It also puts the phenomenology and psychology of solitary confinement to use in the legal context. Not only is there no consensus on whether solitary confinement is a "cruel and unusual punishment," there is no consensus on the definition of the term "cruel" in the use of that legal phrase. I argue that we can find a moral consensus on the meaning of "cruelty" by looking specifically at the phenomenology and psychology of solitary confinement.

  15. Comparison of bed shear under non-breaking and breaking solitary waves

    Digital Repository Service at National Institute of Oceanography (India)

    JayaKumar, S.; Baldock, T.E.

    New experimental measurements of bed shear under solitary waves and solitary bores that represent tsunamis are presented. The total bed shear stress was measured directly using a shear cell apparatus. The solitary wave characteristics were measured...

  16. Bulk solitary waves in elastic solids

    Science.gov (United States)

    Samsonov, A. M.; Dreiden, G. V.; Semenova, I. V.; Shvartz, A. G.

    2015-10-01

    A short and object oriented conspectus of bulk solitary wave theory, numerical simulations and real experiments in condensed matter is given. Upon a brief description of the soliton history and development we focus on bulk solitary waves of strain, also known as waves of density and, sometimes, as elastic and/or acoustic solitons. We consider the problem of nonlinear bulk wave generation and detection in basic structural elements, rods, plates and shells, that are exhaustively studied and widely used in physics and engineering. However, it is mostly valid for linear elasticity, whereas dynamic nonlinear theory of these elements is still far from being completed. In order to show how the nonlinear waves can be used in various applications, we studied the solitary elastic wave propagation along lengthy wave guides, and remarkably small attenuation of elastic solitons was proven in physical experiments. Both theory and generation for strain soliton in a shell, however, remained unsolved problems until recently, and we consider in more details the nonlinear bulk wave propagation in a shell. We studied an axially symmetric deformation of an infinite nonlinearly elastic cylindrical shell without torsion. The problem for bulk longitudinal waves is shown to be reducible to the one equation, if a relation between transversal displacement and the longitudinal strain is found. It is found that both the 1+1D and even the 1+2D problems for long travelling waves in nonlinear solids can be reduced to the Weierstrass equation for elliptic functions, which provide the solitary wave solutions as appropriate limits. We show that the accuracy in the boundary conditions on free lateral surfaces is of crucial importance for solution, derive the only equation for longitudinal nonlinear strain wave and show, that the equation has, amongst others, a bidirectional solitary wave solution, which lead us to successful physical experiments. We observed first the compression solitary wave in the

  17. Synchronization of ;light-sensitive; Hindmarsh-Rose neurons

    Science.gov (United States)

    Castanedo-Guerra, Isaac; Steur, Erik; Nijmeijer, Henk

    2018-04-01

    The suprachiasmatic nucleus is a network of synchronized neurons whose electrical activity follows a 24 h cycle. The synchronization phenomenon (among these neurons) is not completely understood. In this work we study, via experiments and numerical simulations, the phenomenon in which the synchronization threshold changes under the influence of an external (bifurcation) parameter in coupled Hindmarsh-Rose neurons. This parameter ;shapes; the activity of the individual neurons the same way as some neurons in the brain react to light. We corroborate this experimental finding with numerical simulations by quantifying the amount of synchronization using Pearson's correlation coefficient. In order to address the local stability problem of the synchronous state, Floquet theory is applied in the case where the dynamic systems show continuous periodic solutions. These results show how the sufficient coupling strength for synchronization between these neurons is affected by an external cue (e.g. light).

  18. From bell-shaped solitary wave to W/M-shaped solitary wave ...

    Indian Academy of Sciences (India)

    These solitary wave solutions may be applied to neuroscience for providing a math- ematical model and explaining electrophysiological responses of visceral nociceptive neurons and sensitization of dorsal root reflexes [10]. The mathematical results we have obtained about the singular travelling wave equation provide a ...

  19. Solitary lucent epiphyseal lesions in children

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, D.J.; Azouz, E.M.

    1988-10-01

    We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. 40% of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyoxid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion.

  20. Solitary osteoma of body of the mandible

    Directory of Open Access Journals (Sweden)

    Saba Khan

    2013-01-01

    Full Text Available Osteomas are relatively rare benign osteogenic neoplasm′s characterized by the proliferation of compact or cancellous bone. Osteomas can develop as peripheral (periosteal masses attached to the cortical plates or as central lesions arising from endosteal bone surfaces. Although multiple osteomas of the jaws are a hallmark of Gardner′s syndrome (familial adenomatous polyposis, non-syndromic cases are typically solitary. The purpose of this paper is to present a large peripheral osteoma originating from the buccal surface of the mandible and causing asymmetry in a 35-year-old woman.

  1. Microtubules: A network for solitary waves

    Directory of Open Access Journals (Sweden)

    Zdravković Slobodan

    2017-01-01

    Full Text Available In the present paper we deal with nonlinear dynamics of microtubules. The structure and role of microtubules in cells are explained as well as one of models explaining their dynamics. Solutions of the crucial nonlinear differential equation depend on used mathematical methods. Two commonly used procedures, continuum and semi-discrete approximations, are explained. These solutions are solitary waves usually called as kink solitons, breathers and bell-type solitons. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45010

  2. Localization and solitary waves in solid mechanics

    CERN Document Server

    Champneys, A R; Thompson, J M T

    1999-01-01

    This book is a collection of recent reprints and new material on fundamentally nonlinear problems in structural systems which demonstrate localized responses to continuous inputs. It has two intended audiences. For mathematicians and physicists it should provide useful new insights into a classical yet rapidly developing area of application of the rich subject of dynamical systems theory. For workers in structural and solid mechanics it introduces a new methodology for dealing with structural localization and the related topic of the generation of solitary waves. Applications range from classi

  3. Conductive nanogel-interfaced neural microelectrode arrays with electrically controlled in-situ delivery of manganese ions enabling high-resolution MEMRI for synchronous neural tracing with deep brain stimulation.

    Science.gov (United States)

    Huang, Wei-Chen; Lo, Yu-Chih; Chu, Chao-Yi; Lai, Hsin-Yi; Chen, You-Yin; Chen, San-Yuan

    2017-04-01

    Chronic brain stimulation has become a promising physical therapy with increased efficacy and efficiency in the treatment of neurodegenerative diseases. The application of deep brain electrical stimulation (DBS) combined with manganese-enhanced magnetic resonance imaging (MEMRI) provides an unbiased representation of the functional anatomy, which shows the communication between areas of the brain responding to the therapy. However, it is challenging for the current system to provide a real-time high-resolution image because the incorporated MnCl 2 solution through microinjection usually results in image blurring or toxicity due to the uncontrollable diffusion of Mn 2+ . In this study, we developed a new type of conductive nanogel-based neural interface composed of amphiphilic chitosan-modified poly(3,4 -ethylenedioxythiophene) (PMSDT) that can exhibit biomimic structural/mechanical properties and ionic/electrical conductivity comparable to that of Au. More importantly, the PMSDT enables metal-ligand bonding with Mn 2+ ions, so that the system can release Mn 2+ ions rather than MnCl 2 solution directly and precisely controlled by electrical stimulation (ES) to achieve real-time high-resolution MEMRI. With the integration of PMSDT nanogel-based coating in polyimide-based microelectrode arrays, the post-implantation DBS enables frequency-dependent MR imaging in vivo, as well as small focal imaging in response to channel site-specific stimulation on the implant. The MR imaging of the implanted brain treated with 5-min electrical stimulation showed a thalamocortical neuronal pathway after 36 h, confirming the effective activation of a downstream neuronal circuit following DBS. By eliminating the susceptibility to artifact and toxicity, this system, in combination with a MR-compatible implant and a bio-compliant neural interface, provides a harmless and synchronic functional anatomy for DBS. The study demonstrates a model of MEMRI-functionalized DBS based on functional

  4. Synchronicity and Leadership

    NARCIS (Netherlands)

    Merry, Philip

    2017-01-01

    LAY SUMMARY SYNCHRONICITY AND LEADERSHIP TILBURG PHD DISSERTATION, PHILIP MERRY World’s First PhD to Research Synchronicity And Leadership Using Grounded Theory OUT OF THE BLUE COINCIDENCES: research topic Most people have had the experience of thinking of someone and then, almost magically have

  5. Synchronization of networks

    Indian Academy of Sciences (India)

    For networks with time-varying topology we compare the synchronization properties of these networks with the corresponding time-average network. We find that if the different coupling matrices corresponding to the time-varying networks commute with each other then the stability of the synchronized state for both the ...

  6. Solitary drift waves in the presence of magnetic shear

    International Nuclear Information System (INIS)

    Meiss, J.D.; Horton, W.

    1982-07-01

    The two-component fluid equations describing electron drift and ion acoustic waves in a nonuniform magnetized plasma are shown to possess nonlinear two-dimensional solitary wave solutions. In the presence of magnetic shear, radiative shear damping is exponentially small in L/sub s//L/sub n/ for solitary drift waves, in contrast to linear waves

  7. Solitary plane waves in an isotropic hexagonal lattice

    DEFF Research Database (Denmark)

    Zolotaryuk, Yaroslav; Savin, A.V.; Christiansen, Peter Leth

    1998-01-01

    of these solitary waves is investigated numerically by their interactions with vacancies and lattice edges. Propagation of solitary plane waves through finite lattice domains with isotopic disorder is extensively studied. Comparison of these results with the soliton propagation in one-dimensional lattices with mass...

  8. Giant Solitary Hepatocellular Carcinoma. A Case Report. | Asuquo ...

    African Journals Online (AJOL)

    Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver, among indigenous inhabitants of Africa and it may present as solitary or multiple lesions often running a rapidly fatal course. Presented is a case of a 25 year female in apparent general good health with a giant solitary hepatocellular ...

  9. Single-peak solitary wave solutions for the variant Boussinesq ...

    Indian Academy of Sciences (India)

    ∈ H1 loc(R). (iii) Similar to the proof of the above (ii),we omit it here. This completes the proof. 3. Smooth and cusped single-peak solitary wave solutions. Theorem 2.4 gives a classification for all single-peak solitary wave solutions for eq. (2.4).

  10. Intramuscular cysticercosis – The solitary reaper | Singh | Annals of ...

    African Journals Online (AJOL)

    Occurrence of solitary intramuscular cysticercosis without involvement of the central nervous system is rare. We report a case of solitary cysticercosis of the brachioradialis muscle in a 35-year-old woman who presented with discomfort and pain in the right elbow and arm after trivial trauma. There were no systemic or ...

  11. Solitary Plasmacytoma: A Review Of Clinical, Ocular, Neurological ...

    African Journals Online (AJOL)

    Solitary plasmacytomas are defined as proliferation of monoclonal plasma cells without evidence of significant bone-marrow plasma-cell infiltration. They are classified according to location into solitary plasmacytoma of bone if they occur in bone, and extramedullary plasmacytoma if they arise in soft tissues. They are more ...

  12. Solitary neurofibroma of eyelid masquerading as chalazion

    Directory of Open Access Journals (Sweden)

    Chen N

    2017-05-01

    Full Text Available Nancy Chen,1 Yung-Hsiang Hsu,2 Yuan-Chieh Lee1,3 1Department of Ophthalmology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; 2Department of Pathology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; 3Department of Ophthalmology and Visual Science, Tzu Chi University, Hualien, Taiwan Abstract: Neurofibroma, a benign peripheral nerve sheath tumor, usually appears together with café-au-lait spots, iris nodules, and other tumors within the scope of neurofibromatosis von Recklinghausen type 1 tumors. A solitary neurofibroma of the eyelid is relatively rare. In this case report, we present a 39-year-old woman who had a lesion on the eyelid crease, previously treated as a chalazion. Due to persistent wound crusting, the lesion was excised above the tarsus. Pathological examination revealed a solitary neurofibroma. The patient did not have other clinical symptoms of neurofibromatosis, and there was no recurrence of the nodule during the 1-year follow-up. Keywords: neurofibroma, eyelid tumor, chalazion

  13. Radiation therapy for the solitary plasmacytoma

    Directory of Open Access Journals (Sweden)

    Esengül Koçak

    2010-06-01

    Full Text Available Plasma-cell neoplasms are classically categorized into four groups as: multiple myeloma (MM, plasma-cell leukemias, solitary plasmacytomas (SP of the bone (SPB, and extramedullary plasmacytomas (EMP. These tumors may be described as localized or diffuse in presentation. Localized plasma-cell neoplasms are rare, and include SP of the skeletal system, accounting for 2-5% of all plasma-cell neoplasms, and EMP of soft tissue, accounting for approximately 3% of all such neoplasms. SP is defined as a solitary mass of neoplastic plasma cells either in the bone marrow or in various soft tissue sites. There appears to be a continuum in which SP often progresses to MM. The main treatment modality for SP is radiation therapy (RT. However, there are no conclusive data in the literature on the optimal RT dose for SP. This review describes the interrelationship of plasma-cell neoplasms, and attempts to determine the minimal RT dose required to obtain local control.

  14. The solitary sellar plasmacytoma: a diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Anne Soejbjerg

    2016-06-01

    Full Text Available Solitary sellar plasmacytomas are exceedingly rare and difficult to distinguish from other pituitary tumors. We report a case of a 62-year-old woman presenting with blurred vision of the right eye and tenderness of the right temporal region, which was interpreted as temporal arteritis. MRI revealed a pituitary mass lesion (20mm×14mm×17mm without compression of the optic chiasm and her pituitary function was normal. Pituitary surgery was undertaken due to growth of the lesion, and histopathological examination showed a highly cellular neoplasm composed of mature monoclonal plasma cells. Subsequent examinations revealed no evidence of extrasellar myeloma. The patient received pituitary irradiation and has remained well and free of symptoms apart from iatrogenic central diabetes insipidus. Until now, only eight cases of solitary sellar plasmacytoma have been reported. Most frequent symptoms stem from compression of the cranial nerves in the cavernous sinus (III, IV, V, whereas the anterior pituitary function is mostly intact.

  15. Adaptive elimination of synchronization in coupled oscillator

    International Nuclear Information System (INIS)

    Zhou, Shijie; Lin, Wei; Ji, Peng; Feng, Jianfeng; Zhou, Qing; Kurths, Jürgen

    2017-01-01

    We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh–Nagumo spiking oscillators and the Hindmarsh–Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy. (paper)

  16. Adaptive elimination of synchronization in coupled oscillator

    Science.gov (United States)

    Zhou, Shijie; Ji, Peng; Zhou, Qing; Feng, Jianfeng; Kurths, Jürgen; Lin, Wei

    2017-08-01

    We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh-Nagumo spiking oscillators and the Hindmarsh-Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy.

  17. Asynchronized synchronous machines

    CERN Document Server

    Botvinnik, M M

    1964-01-01

    Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids” of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv

  18. Solitary magnetic perturbations at the ELM onset

    Science.gov (United States)

    Wenninger, R. P.; Zohm, H.; Boom, J. E.; Burckhart, A.; Dunne, M. G.; Dux, R.; Eich, T.; Fischer, R.; Fuchs, C.; Garcia-Munoz, M.; Igochine, V.; Hölzl, M.; Luhmann N., C., Jr.; Lunt, T.; Maraschek, M.; Müller, H. W.; Park, H. K.; Schneider, P. A.; Sommer, F.; Suttrop, W.; Viezzer, E.; the ASDEX Upgrade Team

    2012-11-01

    Tokamak H-mode plasmas frequently exhibit edge-localized modes (ELMs). ELMs allow maintaining sufficient plasma purity and thus enable stationary H-mode. On the other hand in a future device ELMs may cause divertor power flux densities far in excess of tolerable material limits. The size of the energy loss per ELM is determined by saturation effects in the non-linear phase of the ELM, which at present is hardly understood. ASDEX Upgrade is now equipped with a set of fast sampling diagnostics, which is well suited to investigate the chain of events around the ELM crash with appropriate temporal resolution (⩽10 µs). Solitary magnetic perturbations (SMPs) are identified as dominant features in the radial magnetic fluctuations below 100 kHz. They are typically observed close (±100 µs) to the onset of pedestal erosion. SMPs are field aligned structures rotating in the electron diamagnetic drift direction with perpendicular velocities of about 10 km s-1. A comparison of perpendicular velocities suggests that the perturbation evoking SMPs is located at or inside the separatrix. Analysis of very pronounced examples showed that the number of peaks per toroidal turn is 1 or 2, which is clearly lower than the corresponding numbers in linear stability calculations. In combination with strong peaking of the magnetic signals this results in a solitary appearance resembling modes like palm tree modes, edge snakes or outer modes. This behaviour has been quantified as solitariness and correlated with main plasma parameters. SMPs may be considered as a signature of the non-linear ELM phase originating at the separatrix or further inside. Thus they provide a handle to investigate the transition from linear to non-linear ELM phase. By comparison with data from gas puff imaging processes in the non-linear phase at or inside the separatrix and in the scrape-off layer (SOL) can be correlated. A connection between the passing of an SMP and the onset of radial filament propagation has

  19. Solitary plasmacytoma of spine with amyloidosis

    Directory of Open Access Journals (Sweden)

    Cui-yun SUN

    2017-01-01

    Full Text Available Objective To report the diagnosis and treatment of one case of solitary plasmacytoma of spine with amyloidosis and investigate the clinicopathological features combined with literatures. Methods and Results The patient was a 46-year-old woman. She suffered from weakness of both lower limbs, unsteady gait and numbness of toes for 20 d. MRI examination revealed an irregular mass behind the spinal cord at T5-7 level and T6-7 vertebral body accessory. The enhanced MRI showed obvious heterogeneous enhancement. The border was clear and spinal dura mater was compressed to shift forward. During operation, T5-7 processus spinosus and vertebral laminae were eroded, and the cortex of bone showed "moth-eaten" erosion. The intraspinal and extradural lesion had rich blood supply, loose bone structure and intact spinal dura mater. Histologically, tumor cells were composed of intensive small cells, and focal plasmacytoid cells were seen. Flake pink staining substance was among them. Artificial cracks were common and multinuclear giant tumor cells were scatteredly distributed. Immunohistochemical analysis showed the cytoplasm of tumor cells were diffusely positive for CD138, CD38 and vimentin (Vim,scatteredly positive for leukocyte common antigen (LCA, and negative for immune globulin κ light chain(IgGκ and λ light chain (IgGλ, CD99, S-100 protein (S-100, pan cytokeratin (PCK, epithelial membrane antigen (EMA, HMB45 and CD34. The Ki-67 labeling index was 1.25%. Congo red staining showed the pink staining substance was brownish red. Hybridization in situ examination showed the DNA content of IgGκ was more than that of IgGλ. The final pathological diagnosis was solitary plasmacytoma of spine with amyloidosis. The patient was treated with postoperative chemotherapy, and there was no recurrence or metastasis during 18-month follow-up period. Conclusions Solitary plasmacytoma of spine with amyloidosis is a rare tumor. The imaging features can offer a few

  20. Dynamical hysteresis and spatial synchronization in coupled non ...

    Indian Academy of Sciences (India)

    behavior of complex biological systems, e.g. seizures in the epileptic brain can be viewed as transitions between different dynamical phases caused by time dependence in the brain's internal coupling. Keywords. Hysteresis; multistability; spatial synchronization; spatio-temporal chaos. PACS Nos 05.45.Xt; 05.45.tp; 05.45.

  1. Emergent explosive synchronization in adaptive complex networks

    Science.gov (United States)

    Avalos-Gaytán, Vanesa; Almendral, Juan A.; Leyva, I.; Battiston, F.; Nicosia, V.; Latora, V.; Boccaletti, S.

    2018-04-01

    Adaptation plays a fundamental role in shaping the structure of a complex network and improving its functional fitting. Even when increasing the level of synchronization in a biological system is considered as the main driving force for adaptation, there is evidence of negative effects induced by excessive synchronization. This indicates that coherence alone cannot be enough to explain all the structural features observed in many real-world networks. In this work, we propose an adaptive network model where the dynamical evolution of the node states toward synchronization is coupled with an evolution of the link weights based on an anti-Hebbian adaptive rule, which accounts for the presence of inhibitory effects in the system. We found that the emergent networks spontaneously develop the structural conditions to sustain explosive synchronization. Our results can enlighten the shaping mechanisms at the heart of the structural and dynamical organization of some relevant biological systems, namely, brain networks, for which the emergence of explosive synchronization has been observed.

  2. Synchronization in complex networks

    Energy Technology Data Exchange (ETDEWEB)

    Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

    2007-12-12

    Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  3. Solitary, explosive and periodic solutions for electron acoustic solitary waves with non-thermal hot ions

    Science.gov (United States)

    Elwakil, S. A.; Abulwafa, E. M.; El-Shewy, E. K.; Abd-El-Hamid, H. M.

    2011-11-01

    A theoretical investigation has been made for electron acoustic waves propagating in a system of unmagnetized collisionless plasma consists of a cold electron fluid and ions with two different temperatures in which the hot ions obey the non-thermal distribution. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation for small but finite amplitude electrostatic waves. It is found that the presence of the energetic population of non-thermal hot ions δ, initial normalized equilibrium density of low temperature ions μ and the ratio of temperatures of low temperature ions to high temperature ions β do not only significantly modify the basic properties of solitary structure, but also change the polarity of the solitary profiles. At the critical hot ions density, the KdV equation is not appropriate for describing the system. Hence, a new set of stretched coordinates is considered to derive the modified KdV equation. In the vicinity of the critical hot ions density, neither KdV nor modified KdV equation is appropriate for describing the electron acoustic waves. Therefore, a further modified KdV equation is derived. An algebraic method with computerized symbolic computation, which greatly exceeds the applicability of the existing tanh, extended tanh methods in obtaining a series of exact solutions of the various KdV-type equations, is used here. Numerical studies have been reveals different solutions e.g., bell-shaped solitary pulses, singular solitary "blowup" solutions, Jacobi elliptic doubly periodic wave, Weierstrass elliptic doubly periodic type solutions, in addition to explosive pulses. The results of the present investigation may be applicable to some plasma environments, such as Earth's magnetotail region.

  4. Synchronous DC Power Supply.

    Science.gov (United States)

    The patent describes a synchronous direct current (dc) power supply which has the power supply input drive synchronized with the pulse repetition...frequency (PRF) of the amplifying or load circuit requiring the dc power for operation. This limits the occurrence of ripple components in the power ... supply output to the spectral positions of the PRF lines, eliminating ripple interference with signal processing in the load. An astable multivibrator is

  5. Solitary Plasmacytoma of the Chest Wall

    Directory of Open Access Journals (Sweden)

    Servet Kayhan

    2014-03-01

    Full Text Available A previously healthy 55-year-old man with right sided lateral chest pain admitted to clinic. It was found a solid and painful mass at the right 4th rib in physical examination. Chest X-ray and thoracic computarized tomography showed an opacity measured 60x33 mm within the right chest wall destructing the 4th rib. Needle aspiration was performed from tumor and cytologic examination showed atypic plasma cell infiltration. The patient was scheduled for a chest wall resection and reconstructive surgery. Examination of a permanent section showed that the chest wall tumor was solitary plasmacytoma. There was no evidence of multiple myeloma recurrence after two years from the operation.

  6. A solitary fibrous tumor of the kidney

    Directory of Open Access Journals (Sweden)

    Anuruddha M Abeygunasekera

    2015-01-01

    Full Text Available A solitary fibrous tumor (SFT is an uncommon spindle cell neoplasm that usually occurs in the pleura, but may occur in extrapleural sites. Its occurrence in the kidney is rare. We report a SFT, clinically thought to be a renal cell carcinoma arising in the kidney of a 68-year-old female. The tumor was well-circumscribed and composed of a mixture of spindle cells and dense collagenous bands. Immunohistochemical studies revealed reactivity for CD34, CD99, and Bcl-2 protein, with no staining for keratin or muscle markers, confirming the diagnosis. The immunohistochemical study was the key to diagnosis. Several younger members of her family had colorectal and lung cancers suggesting the possibility of a familial or genetic susceptibility.

  7. Benign solitary solid cold thyroid nodules

    DEFF Research Database (Denmark)

    Døssing, Helle; Bennedbaek, Finn Noe; Karstrup, Steen

    2002-01-01

    PURPOSE: To evaluate the effects of ultrasonography (US)-guided interstitial laser photocoagulation (ILP) on the volume of benign solitary solid cold thyroid nodules and any nodule-related symptoms. MATERIALS AND METHODS: ILP was performed in 16 patients with normal thyroid function and a solid...... benign thyroid nodule. None of the patients had uptake on a radionuclide scan. Patients underwent one ILP session. A needle was positioned in the thyroid nodule with US guidance, and the laser fiber was placed in the lumen of the needle. Patients were treated for 287-1,200 seconds with an output power...... of 1-3 W. ILP was performed with continuous US guidance and terminated when the echogenic changes were stationary. Thyroid nodule volume and thyroid function were evaluated before and 1, 3, and 6 months after treatment. During the same period, 15 untreated patients (control group) were followed up...

  8. Electromagnetic solitary waves in magnetized plasmas

    International Nuclear Information System (INIS)

    Hazeltine, R.D.; Holm, D.D.; Morrison, P.J.

    1985-03-01

    A Hamiltonian formulation, in terms of noncanonical Poisson bracket, is presented for a nonlinear fluid system that includes reduced magnetohydrodynamics and the Hasegawa-Mima equation as limiting cases. The single-helicity and axisymmetric versions possess three nonlinear Casimir invariants, from which a generalized potential can be constructed. Variation of the generalized potential yields a description of exact nonlinear stationary states. The new equilibria, allowing for plasma flow as well as partial electron adiabaticity, are distinct from those found in conventional magnetohydrodynamic theory. They differ from electrostatic stationary states in containing plasma current and magnetic field excitation. One class of steady-state solutions is shown to provide a simple electromagnetic generalization of drift-solitary waves

  9. Solitary Rectal Ulcer Syndrome: A Biopsychosocial Assessment

    Directory of Open Access Journals (Sweden)

    Hamed Daghaghzadeh

    2016-06-01

    Full Text Available Background: Solitary rectal ulcer syndrome (SRUS is a chronic disorder of the gastrointestinal tract and its etiology is not well understood. There is no specific treatment for this syndrome and patients with SRUS may, for years, experience many complications. The aim of the present research was the biopsychosocial study of patients with SRUS.Methods: The study participants consisted of 16 patients with SRUS (7 men and 9 women. Their medical records were reviewed retrospectively to evaluate the clinical spectrum of the patients along with the endoscopic and histological findings. Moreover, psychiatric and personality disorders [based on Diagnostic and Statistical Manual of Mental Disorders, 4th ed, Text Revision (DSM IV-TR], psychosocial stressors, early life traumas, and coping mechanisms were assessed through structured interviews.Results: At presentation, mean age of the patients was 39 years (16 to 70. Common symptoms reported included rectal bleeding (93.8%, rectal self-digitations (81.2%, passage of mucous (75%, anal pain (75%, and straining (75%. Endoscopically, solitary and multiple lesions were present in 9 (60% and 4 (26.7% patients, respectively, and 87% of lesions were ulcerative and 13.3% polypoidal. The most common histological findings were superficial ulceration (92.85% and intercryptic fibromuscular obliteration (87.71%. Common psychosocial findings included anxiety disorders (50%, depression (37.5%, obsessive-compulsive personality disorder (OCPD or traits (62.5%, interpersonal problems (43.75%, marital conflicts (43.75%, occupational stress (37.5%, early life traumas, physical abuse (31.25%, sexual abuse (31.25%, dysfunctional coping mechanisms, emotional inhibition (50%, and non-assertiveness (37.5%.Conclusion: Given the evidence in this study, we cannot ignore the psychosocial problems of patients with SRUS and biopsychosocial assessment of SRUS is more appropriate than biomedical evaluation alone.

  10. Widespread occurrence of honey bee pathogens in solitary bees.

    Science.gov (United States)

    Ravoet, Jorgen; De Smet, Lina; Meeus, Ivan; Smagghe, Guy; Wenseleers, Tom; de Graaf, Dirk C

    2014-10-01

    Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Solitary fibrous tumor of the orbit with intracranial involvement.

    Science.gov (United States)

    Young, Thomas K; Hardy, Thomas G

    2011-01-01

    Solitary fibrous tumor of the orbit is a rare neoplasm that often follows a benign course. Additional involvement beyond the orbit is even rarer, having only been reported in 2 cases previously. The authors describe a 62-year-old patient with a primarily intracranial lesion including orbital extension which was debulked and initially diagnosed as meningioma. Two recurrences 3 and 4 years later disclosed a solitary fibrous tumor, with the initial histopathology being revised to the same diagnosis. This rare presentation of an orbital solitary fibrous tumor highlights the surgical challenge faced when the tumor straddles the cranio-orbital junction and demonstrates the potential for rapid regrowth after incomplete excision.

  12. Robust Master-Slave Synchronization of Neuronal Systems

    Directory of Open Access Journals (Sweden)

    Hector Puebla

    2017-01-01

    Full Text Available The desire to understand physiological mechanisms of neuronal systems has led to the introduction of engineering concepts to explain how the brain works. The synchronization of neurons is a central topic in understanding the behavior of living organisms in neurosciences and has been addressed using concepts from control engineering. We introduce a simple and reliable robust synchronization approach for neuronal systems. The proposed synchronization method is based on a master-slave configuration in conjunction with a coupling input enhanced with compensation of model uncertainties. Our approach has two nice features for the synchronization of neuronal systems: (i a simple structure that uses the minimum information and (ii good robustness properties against model uncertainties and noise. Two benchmark neuronal systems, Hodgkin-Huxley and Hindmarsh-Rose neurons, are used to illustrate our findings. The proposed synchronization approach is aimed at gaining insight into the effect of external electrical stimulation of nerve cells.

  13. Emergence of dynamical order synchronization phenomena in complex systems

    CERN Document Server

    Manrubia, Susanna C; Zanette, Damián H

    2004-01-01

    Synchronization processes bring about dynamical order and lead tospontaneous development of structural organization in complex systemsof various origins, from chemical oscillators and biological cells tohuman societies and the brain. This book provides a review and adetailed theoretical analysis of synchronization phenomena in complexsystems with different architectures, composed of elements withperiodic or chaotic individual dynamics. Special attention is paid tostatistical concepts, such as nonequilibrium phase transitions, orderparameters and dynamical glasses.

  14. Synchronizing weighted automata

    Directory of Open Access Journals (Sweden)

    Szabolcs Iván

    2014-05-01

    Full Text Available We introduce two generalizations of synchronizability to automata with transitions weighted in an arbitrary semiring K=(K,+,*,0,1. (or equivalently, to finite sets of matrices in K^nxn. Let us call a matrix A location-synchronizing if there exists a column in A consisting of nonzero entries such that all the other columns of A are filled by zeros. If additionally all the entries of this designated column are the same, we call A synchronizing. Note that these notions coincide for stochastic matrices and also in the Boolean semiring. A set M of matrices in K^nxn is called (location-synchronizing if M generates a matrix subsemigroup containing a (location-synchronizing matrix. The K-(location-synchronizability problem is the following: given a finite set M of nxn matrices with entries in K, is it (location-synchronizing? Both problems are PSPACE-hard for any nontrivial semiring. We give sufficient conditions for the semiring K when the problems are PSPACE-complete and show several undecidability results as well, e.g. synchronizability is undecidable if 1 has infinite order in (K,+,0 or when the free semigroup on two generators can be embedded into (K,*,1.

  15. Treatment of metastatic brain lesion

    Directory of Open Access Journals (Sweden)

    A. M. Zaytsev

    2015-01-01

    Full Text Available Objective. Increasing survival in patients with secondary brain damage, and identifying the factors of favorable and adverse prognosis.Material and method. In P. A. Hertsen Moscow Oncology Research Institute from 2007 to 2013 there were treated 268 patients with brain metastases. The mean age was 55.8 years (from 24 to 81 years. Metastases of colorectal cancer identified in 7.8%, cases of lung cancer in 34%, melanoma 9.3 %, breast cancer in 26%, kidney cancer in 11%, with non-identified primary tumor in 4.5%, other tumors accounted for 6.7%. Solitary metastasis was diagnosed in 164 (61,19% patients, oligometastasis (2-3 - 72 (26,87% patients with polymetastasis (more than 3 – 32 (11,94% patients. In 106 (39,55% of patients with brain metastases it was the only manifestation of the generalization process. To control the radical removal of the tumor in 93 (34,7% patients we used the method of fluorescence navigation (FN with the drug Alasens. In 66 (24,6% patients intraoperatively was held a session of photodynamic therapy (PDT. In 212 (79,1% cases, the removal of metastasis performed totally, 55 (20,9% patients stated Subtotal removal.Results. The observation period for the patients ranged from 3 to 79 months. Survival median among the entire group of patients with metastatic brain lesion was 12 months. Overall survival was significantly dependent on RPA class, the volume of postoperative treatment, histological type of primary tumor, number of intracerebral metastases and the timing of the relapse-free period.Conclusions. Factors that affects the overall survival are the features of the histology of the primary lesion, multiplicity of metastatic lesions, RPA class and the synchronous nature of the metastasis. The median of overall survival of patients who did not receive after surgical treatment of a particular type of therapy was only 4 months. If to use the combined treatment (surgical treatment with the irradiation of the whole brain median

  16. Solitary osteochondroma arising from cervical spina bifida occulta.

    Science.gov (United States)

    Ofluoglu, Ali Ender; Abdallah, Anas; Gokcedag, Akin

    2013-01-01

    Solitary osteochondromas are common benign long bone tumors originating from cartilage. They may produce a wide variety of symptoms and complications depending on their spinal location. These may include compressive myelopathy, nerve root compression, pathologic fracture and malignant degeneration, or in some cases only pain. Solitary cervical spine osteochondromas have been reported mostly in the neural arch or vertebral body. This report describes a patient presenting with neck pain, with a benign osteochondroma arising in the right bifid C5 lamina.

  17. Reducing the use and impact of solitary confinement in corrections.

    Science.gov (United States)

    Ahalt, Cyrus; Haney, Craig; Rios, Sarah; Fox, Matthew P; Farabee, David; Williams, Brie

    2017-03-13

    Purpose Although the reform of solitary confinement is underway in many jurisdictions around world, isolation remains in widespread use in many jails and prisons. The purpose of this paper is to discuss opportunities for reform in the USA that could also be applied globally. Design/methodology/approach A review of the evidence on solitary confinement policies and practices in the USA to develop recommendations for reform with global application. Findings Focusing on this evidence, the authors argue that solitary confinement is overused and recommend a multi-level approach available to correctional systems worldwide including: immediately limiting solitary confinement to only those cases in which a violent behavioral infraction has been committed for which safety cannot otherwise be achieved, ensuring the briefest terms of isolation needed to achieve legitimate and immediate correctional goals, prohibiting its use entirely for some populations, regularly reviewing all isolated prisoners for as-soon-as-possible return to general population, including the immediate return of those showing mental and physical health risk factors, assisting individuals who are transitioning out of isolation (either to the general population or to the community), and partnering with medical, public health, and criminal justice experts to develop evidence-based alternatives to solitary confinement for nearly all prisoners. Originality/value This paper provides an overview of the evidence supporting an overhaul of solitary confinement policy in the USA and globally where solitary confinement remains in wide use and offers recommendations for immediate steps that can be taken toward achieving evidence-based solitary confinement reform.

  18. Spontaneous Remission of Solitary-Type Infantile Myofibromatosis

    Directory of Open Access Journals (Sweden)

    Kazuhiro Kikuchi

    2011-08-01

    Full Text Available Infantile myofibromatosis is a rare fibrous tumor of infancy. The cutaneous solitary type has typically an excellent prognosis. However, histologically, it is important to rule out leiomyosarcoma, which has a poor prognosis. The low frequency of mitosis was definitive for a diagnosis of infantile myofibromatosis. We present a cutaneous solitary-type case of infantile myofibromatosis. Following incisional biopsy, the tumor remitted spontaneously.

  19. THE STUDY OF CLINICAL PRESENTATION OF SOLITARY NODULE THYROID

    Directory of Open Access Journals (Sweden)

    Lakshmikanthan Premalatha

    2017-07-01

    Full Text Available BACKGROUND Thyroid disorders are the most common endocrine disorder seen in clinical practice and solitary thyroid nodule is one of the common presentations of thyroid disease. A discrete swelling in an otherwise impalpable gland is termed isolated or solitary nodule of thyroid.1 The prevalence of thyroid nodule increases from near zero at 15 years to 50% by about 60 to 65 years on sonography. At most 10% of these nodules are palpable even by experienced clinicians. This study is about the clinical presentation, histopathology and management of solitary nodule thyroid in MGM GH Tiruchirappalli. AIMS AND OBJECTIVES- To determine the age and sex incidence among the cases of solitary nodule thyroid. To study the percentage of euthyroid, hypothyroid or hyperthyroid state in patients presenting with solitary nodule thyroid. To study the proportion of malignant and benign cases among the solitary nodule thyroid at M.G.M. Govt. Hospital, Tiruchirappalli. MATERIALS AND METHODS This study includes 58 cases of solitary nodule of thyroid noted during the period Jan 2016-Dec 2016. Factors were tabulated and analysed statistically. RESULTS From the present study, the mean age at presentation found to be 42.5 years with preponderance to females. Because of periods of fluctuations in the demands of the hormonal requirement in female in their life cycle (puberty, menstrual cycles, pregnancy, menopause, the chances of thyroid nodule formation are very high as compared with male counterparts. From the study, distribution of malignancy is about 10.34. The incidence of malignancy found to be 12%, sensitivity is 87.5%, specificity is 100% for FNAC and HPE. CONCLUSION Majority of the patients are between 30-49 years of age. Incidence of solitary thyroid nodule is more common in female. Female: male ratio is almost about 15:1 Commonest symptom is swelling over anterior or lateral aspect of neck Among the benign lesion dominant nodule is most common and papillary and

  20. Solitary necrotic nodule of the liver: parasitic origin?

    OpenAIRE

    Tsui, W. M.; Yuen, R. W.; Chow, L. T.; Tse, C. C.

    1992-01-01

    AIMS: To report further cases of solitary necrotic nodule of the liver and to study its nature. METHODS: Seven nodules were retrieved from 4000 necropsy and surgical liver specimens coming to light over the past five years. All of them satisfied the diagnostic criteria of solitary necrotic nodule: a solid lesion with a central necrotic core and a hyalinised fibrotic capsule containing elastic fibres. Their clinicopathological features were reviewed. RESULTS: The nodules were incidental findin...

  1. The solitary electromagnetic waves in the graphene superlattice

    International Nuclear Information System (INIS)

    Kryuchkov, Sergey V.; Kukhar', Egor I.

    2013-01-01

    d’Alembert equation written for the electromagnetic waves propagating in the graphene superlattice is analyzed. The possibility of the propagation of the solitary electromagnetic waves in the graphene superlattice is discussed. The amplitude and the width of the electromagnetic pulse are calculated. The drag current induced by such wave across the superlattice axis is investigated. The numerical estimate of the charge dragged by the solitary wave is made.

  2. Comparison of solitary cerebral metastasis and glioblastoma multiform

    International Nuclear Information System (INIS)

    Kim, Hyun Cheol; Choi, Woo Suk; Kim, Eui Jong; Oh, Joo Hyeong; Yoon, Yup

    1996-01-01

    The purpose of this study is to evaluate the MR images of solitary cerebral metastasis and glioblastoma multiform to determine the differential findings. Ten cases of solitary cerebral metastasis and 14 cases of glioblastoma multiform were retrospectively reviewed, all of which were proved by pathologically. The MR findings were compared in regard to tumor size and location, degree of edema, enhancement pattern, and shape of rime enhancement. Mean maximum diameter or solitary cerebral metastasis was 3.85 cm(s.d. 1.47). Metastatic lesions were located in corticomedullary junction(70%) with cerebellum in 2 cases. The locations of glioblastoma multiform were white matter(64%) without cerebellar involvement and the mean maximum diameter was 5.43 cm(s.d. 0.99). In solitary cerebral metastasis, the size of edema was larger than the tumor diameter in 50%, but glioblastoma multiform did not show severe degree of edema. Rim enhancement seen in 7 cases of solitary cerebral metastasis showed unilocular shape and complete rim in 6 cases, and even thickness and smooth inner margine in 5 cases. However, rim enhancement seen in 11 cases of glioblastoma multiform showed multilocular appearance with septa in all cases, incomplete rim in 5 cases, and uneven thickness and irregular inner margin in 10 cases. Tumor location, degree of edema, and rim enhancement pattern on Gd-enhanced MR may be useful in differentiation between solitary cerebral metastasis and glioblastoma multiform

  3. TRPM5-expressing solitary chemosensory cells respond to odorous irritants.

    Science.gov (United States)

    Lin, Weihong; Ogura, Tatsuya; Margolskee, Robert F; Finger, Thomas E; Restrepo, Diego

    2008-03-01

    Inhaled airborne irritants elicit sensory responses in trigeminal nerves innervating the nasal epithelium, leading to protective reflexes. The sensory mechanisms involved in the detection of odorous irritants are poorly understood. We identified a large population of solitary chemosensory cells expressing the transient receptor potential channel M5 (TRPM5) using transgenic mice where the promoter of TRPM5 drives the expression of green fluorescent protein (GFP). Most of these solitary chemosensory cells lie in the anterior nasal cavity. These GFP-labeled solitary chemosensory cells exhibited immunoreactivity for synaptobrevin-2, a vesicle-associated membrane protein important for synaptic transmission. Concomitantly, we found trigeminal nerve fibers apposed closely to the solitary chemosensory cells, indicating potential transmission of sensory information to trigeminal fibers. In addition, stimulation of the nasal cavity with high concentrations (0.5-5 mM) of a variety of odorants elicited event-related potentials (ERPs) in areas rich in TRPM5-expressing solitary chemosensory cells. Furthermore, odorous chemicals and trigeminal stimuli induced changes in intracellular Ca(2+) levels in isolated TRPM5-expressing solitary chemosensory cells in a concentration-dependent manner. Together, our data show that the TRPM5-expressing cells respond to a variety of chemicals at high exposure levels typical of irritants and are positioned in the nasal cavity appropriately to monitor inhaled air quality.

  4. Optimistic barrier synchronization

    Science.gov (United States)

    Nicol, David M.

    1992-01-01

    Barrier synchronization is fundamental operation in parallel computation. In many contexts, at the point a processor enters a barrier it knows that it has already processed all the work required of it prior to synchronization. The alternative case, when a processor cannot enter a barrier with the assurance that it has already performed all the necessary pre-synchronization computation, is treated. The problem arises when the number of pre-sychronization messages to be received by a processor is unkown, for example, in a parallel discrete simulation or any other computation that is largely driven by an unpredictable exchange of messages. We describe an optimistic O(log sup 2 P) barrier algorithm for such problems, study its performance on a large-scale parallel system, and consider extensions to general associative reductions as well as associative parallel prefix computations.

  5. Giant solitary fibrous tumour of the liver

    Directory of Open Access Journals (Sweden)

    Eggermont Alexander MM

    2006-11-01

    Full Text Available Abstract Background Solitary fibrous tumour (SFT is an uncommon mesenchymal neoplasm that most frequently affects the pleura, although it has been reported with increasing frequency in various other sites such as in the peritoneum, pericardium and in non-serosal sites such as lung parenchyma, upper respiratory tract, orbit, thyroid, parotid gland, or thymus. Liver parenchyma is rarely affected. Clinically, SFTs cause symptoms after having reached a certain size or when vital structures are involved. In recent years, SFTs are more often identified and distinguished from other tumours with a similar appearance due to the availability of characteristic immunohistochemical markers. Case presentation In this manuscript we report the case of a large tumour of the liver, which was histologically diagnosed as a SFT, and showed involvement of a single hepatic segment. Because of the patient's presentation and clinical course, it may represent a radiation-induced lesion. Conclusion When a SFT has been diagnosed, surgery is the treatment of choice. The small number of patients with a SFT of the liver and its unknown natural behaviour creates the need to a careful registration and follow-up of all identified cases

  6. Food searching and superparasitism in solitary parasitoids

    Science.gov (United States)

    Sirot, Etienne; Bernstein, Carlos

    Optimality theory predicts that, provided that a larva resulting from superparasitism has some chance of winning the competition with the other larvae present in the host, under certain conditions, solitatry parasitoids should resort to superparasitism. Both theoretical and experimental studies have shown that the life expectancy of the parasitoid has a strong influence on the decision to reject or to accept superparasitism. In many species, life expectancy on its turn depends on the feeding behaviour of the parasitoids, which have to forage for non-host food (mainly plant materials), for the maintenance of their energy reseves. As many solitary parasitoids do not find non-host food in their host patches, they have to choose at each instant whether to search for food or to search for hosts. In this paper, we develop a stochastic dynamic programming model to study the behavioural choice between host and food searching, and its consequences for the acceptance and rejection of superparasitism. We study the influence of habitat quality and parasitoid physiological state on the optimal choice. The model predicts that the crucial point determining the optimal strategy is the balance between egg-and time-limitation.

  7. Guideline on management of solitary pulmonary nodule.

    Science.gov (United States)

    Álvarez Martínez, Carlos J; Bastarrika Alemañ, Gorka; Disdier Vicente, Carlos; Fernández Villar, Alberto; Hernández Hernández, Jesús R; Maldonado Suárez, Antonio; Moreno Mata, Nicolás; Rosell Gratacós, Antoni

    2014-07-01

    The aim of the proposed recommendations is be a tool to facilitate decision-making in patients with a solitary pulmonary nodule (SPN). For an optimal decision, accessibility to the different diagnostics techniques and patient preferences need to be incorporated. The first assessment, which includes a chest computed tomography scan, separates a group of patients with extrapulmonary neoplasm or a high surgical risk who require individualized management. Another two groups of patients are patients with SPN up to 8mm and those who have a subsolid SPN, for which specific recommendations are established. SPN larger than 8mm are classified according to their probability of malignancy into low (less than 5%), where observation is recommended, high (higher than 65%), which are managed with a presumptive diagnosis of localized stage carcinoma, and intermediate, where positron emission tomography-computed tomography has high yield for reclassifying them into high or low probability. In cases of intermediate or high probability of malignancy, transbronchial needle aspiration or biopsy of the nodule may be an option. Radiologic observation with low radiation computed tomography without contrast is recommended in SPN with low probability of malignancy, and resection with videothoracoscopy in undiagnosed cases with intermediate or high probability of malignancy. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  8. Solid solitary hamartoma of the spleen

    Directory of Open Access Journals (Sweden)

    Grubor Nikica

    2013-01-01

    Full Text Available Introduction. Hamartoma of the spleen is a rare, sometimes asymptomatic similar to hemangioma benign tumor of the spleen, which, owing to the new diagnostic imaging methods, is discovered with increasing frequency. It appears as solitary or multiple tumorous lesions. Case Outline. We present a 48-year-old woman in whom, during the investigation for Helicobacter pylori gastric infection and rectal bleeding, with ultrasonography, a mass 6.5×6.5 cm in diameter was discovered by chance within the spleen. Splenectomy was performed due to suspected lymphoma of the spleen. On histology, tumor showed to be of mixed cellular structure, with areas without white pulp, at places with marked dilatation of sinusoids and capillaries to the formation of „blood lakes“ between which broad hypercellular Billroth’s zones were present. Extramedullary hematopoiesis was found focally. The cells that covered vascular spaces were CD34+ and CD31+ and CD8- and CD21-. Conclusion. Hamartoma has to be taken into consideration always when well circumscribed hypervascular tumor within the spleen is found, particularly in children. Although the diagnosis of hamartoma may be suspected preoperatively, the exact diagnosis is established based on histological and immunohystochemistry examinations. Treatment is most often splenectomy and rarely a partial splenectomy is possible, which is recommended particularly in children.

  9. TERT promoter mutations and prognosis in solitary fibrous tumor.

    Science.gov (United States)

    Bahrami, Armita; Lee, Seungjae; Schaefer, Inga-Marie; Boland, Jennifer M; Patton, Kurt T; Pounds, Stanley; Fletcher, Christopher D

    2016-12-01

    Solitary fibrous tumor is a mesenchymal neoplasm exhibiting a broad spectrum of biological behavior and harboring the NAB2-STAT6 fusion. Clinicopathologic parameters are currently used in risk-prediction models for solitary fibrous tumor, but the molecular determinants of malignancy in solitary fibrous tumors remain unknown. We proposed that the activation of telomere maintenance pathways confers a perpetual malignant phenotype to these tumors. Therefore, we investigated telomerase reverse transcriptase (TERT) reactivation induced by promoter mutations as a potential molecular mechanism for aggressive clinical behavior in solitary fibrous tumor. The retrospective study included tumor samples from 94 patients with solitary fibrous tumor (31 thoracic and 63 extra-thoracic). Follow-up information was available for 68 patients (median, 46 months). TERT promoter mutation analysis was performed by PCR and Sanger sequencing, and TERT mRNA expression was assessed by real-time quantitative reverse transcription PCR. Patients were stratified into clinicopathologic subgroups (high-risk (n=20), moderate-risk (n=28), and low-risk (n=46)) according to the risk-stratification model proposed by Demicco et al. TERT promoter mutations were identified in 26 of 94 (28%) solitary fibrous tumors: -124C>T in 23 tumors (88%), -124C>A in 1 tumor (4%), and -146C>T in 2 tumors (8%). Real-time quantitative reverse transcription PCR revealed that TERT mRNA expression was higher in all solitary fibrous tumors with the mutant TERT promoter than those with the wild-type TERT promoter. TERT promoter mutations were strongly associated with high-risk clinicopathologic characteristics and outcome. An adverse event (relapse, death) occurred in 16 of 68 (24%) patients, 12 with solitary fibrous tumors with TERT promoter mutations and 4 with the wild-type TERT promoter. TERT promoter mutations were strongly associated with older age (P=0.006), larger tumor size (P=0.000002), higher risk classifications

  10. Synchronization of stochastic systems: from paddlefish electroreceptors to human epileptic glial cell cultures

    Science.gov (United States)

    Neiman, Alexander

    2000-03-01

    Synchronization is one of the fundamental nonlinear phenomena observed in nature. We have studied stochastic synchronization in the electrosensitive system of the paddlefish, Polyodon spathula and have also applied synchronization analysis to networks of glial cells cultured from brain tissue of patients with severe epilepsy. We also present theoretical and numerical models for stochastic synchronization. The electrosensitive system of the paddlefish consists of tens of thousands of electroreceptors located mainly on the "rostrum", which serves as an antenna to locate plankton. Each electroreceptor is a noisy oscillator with natural frequencies in the range of 30-90 Hz. We study synchronization in vivo due to 3-20 Hz external periodic electric fields, which correspond to natural signals produced by Daphnia, the usual prey of paddlefish. We find that for signals whose strengths are in the range that paddlefish customarily encounter in the wild, synchronization coding offers a plausible alternative to the more usual rate coding. We also have studied mutual synchronization between different electroreceptors. Although the spontaneous firing of distant electroreceptors is not synchronized, synchronization is observed when external periodic or even noisy electric fields are applied. We have applied the same analysis techniques to examine synchronization between groups of glial cells. In contrast to cultures of healthy astrocytes, which demonstrate calcium waves, the networks from epileptic tissue are characterized by spatially disordered hyper activity. Nevertheless, we have found that, in many cases, synchronized activity is a rather typical for tissue taken from the uncus region of the brain.

  11. Synchronization of networks

    Indian Academy of Sciences (India)

    time. Both the number of nodes and the edges connecting the nodes can vary with time. Such a time-varying topology can occur in social networks, computer networks, WWW, biological systems, spread of epidemics etc. Here, we investigate the synchronization properties of networks with time-varying structure and compare.

  12. Synchronization of networks

    Indian Academy of Sciences (India)

    We study the synchronization of coupled dynamical systems on networks. The dynamics is governed by a local nonlinear oscillator for each node of the network and interactions connecting different nodes via the links of the network. We consider existence and stability conditions for both single- and multi-cluster ...

  13. (statcom) in synchronous compensator

    African Journals Online (AJOL)

    eobe

    for adoption of advanced control technologies such as Flexible Alternating Current Transmission System (FACTS) with fast ... APPLICATION OF STATIC SYNCHRONOUS COMPENSATOR (STATCOM) IN IMPROVING POWER SYSTEM PERFORMANCE, R.A Jokojeje .... supply at bus i and is the reactive power demand at.

  14. Polysialic Acid Regulates Sympathetic Outflow by Facilitating Information Transfer within the Nucleus of the Solitary Tract.

    Science.gov (United States)

    Bokiniec, Phillip; Shahbazian, Shila; McDougall, Stuart J; Berning, Britt A; Cheng, Delfine; Llewellyn-Smith, Ida J; Burke, Peter G R; McMullan, Simon; Mühlenhoff, Martina; Hildebrandt, Herbert; Braet, Filip; Connor, Mark; Packer, Nicolle H; Goodchild, Ann K

    2017-07-05

    Expression of the large extracellular glycan, polysialic acid (polySia), is restricted in the adult, to brain regions exhibiting high levels of plasticity or remodeling, including the hippocampus, prefrontal cortex, and the nucleus of the solitary tract (NTS). The NTS, located in the dorsal brainstem, receives constant viscerosensory afferent traffic as well as input from central regions controlling sympathetic nerve activity, respiration, gastrointestinal functions, hormonal release, and behavior. Our aims were to determine the ultrastructural location of polySia in the NTS and the functional effects of enzymatic removal of polySia, both in vitro and in vivo polySia immunoreactivity was found throughout the adult rat NTS. Electron microscopy demonstrated polySia at sites that influence neurotransmission: the extracellular space, fine astrocytic processes, and neuronal terminals. Removing polySia from the NTS had functional consequences. Whole-cell electrophysiological recordings revealed altered intrinsic membrane properties, enhancing voltage-gated K + currents and increasing intracellular Ca 2+ Viscerosensory afferent processing was also disrupted, dampening low-frequency excitatory input and potentiating high-frequency sustained currents at second-order neurons. Removal of polySia in the NTS of anesthetized rats increased sympathetic nerve activity, whereas functionally related enzymes that do not alter polySia expression had little effect. These data indicate that polySia is required for the normal transmission of information through the NTS and that changes in its expression alter sympathetic outflow. polySia is abundant in multiple but discrete brain regions, including sensory nuclei, in both the adult rat and human, where it may regulate neuronal function by mechanisms identified here. SIGNIFICANCE STATEMENT All cells are coated in glycans (sugars) existing predominantly as glycolipids, proteoglycans, or glycoproteins formed by the most complex form of

  15. Solitary pancreas retransplant: Study of 22 cases

    Directory of Open Access Journals (Sweden)

    Tércio Genzini

    2006-03-01

    Full Text Available Objective: To present our experience with pancreas retransplantin patients previously submitted to simultaneous pancreas-kidneytransplant, pancreas after kidney transplant and pancreastransplant alone. Methods: Between January/1996 and December/2005, 330 pancreas transplants were performed: 308 primarytransplants and 22 (6% retransplants of solitary pancreas. Thefollowing variables were analyzed: patient age; time elapsedbetween the first and the second transplant; causes of loss of thefirst graft; technical characteristics of the transplant andretransplant and the criteria for selecting donors for retransplant.These clinical data were submitted to statistical analysis. Results:The mean age of patients was 34.3 years and the mean elapsedtime between the first and second transplant was 19.3 months.The causes of the first graft loss were venous (8; 35% and arterial(5; 23% thrombosis, chronic rejection (4; 18%, ischemia/reperfusion injury (2, reflux pancreatitis (1, primary non-function(1 and sepsis (1. A second transplant was performed in thesame iliac fossa in 16 patients (72%. Venous drainage wasperformed in the iliac vein in 16 patients (72%, in the inferior venacava in 5 patients (22% and in the portal vein in one patient. 6 allbladder drainage was the technique used in 18 (82% cases andenteric drainage, in 4 patients (18%. Immunosuppressive regimenapplied to all cases was quadruple therapy with antilymphocyteinduction, tacrolimus, mycophenolate mofetil and steroids. Therewas one early death due to sepsis. One-year patient and pancreasgraft survival rates for retransplants were, respectively, 95% and85%. There was no additional risk for removing the pancreas graftat retransplant. Conclusion: Pancreas retransplant was technicallyfeasible in all cases and results similar to those described in theliterature were found for primary pancreas transplant.

  16. Imaging features of intracranial solitary fibrous tumors

    International Nuclear Information System (INIS)

    Yu Shuilian; Man Yuping; Ma Longbai; Liu Ying; Wei Qiang; Zhu Youkai

    2012-01-01

    Objective: To summarize the imaging features of intracranial solitary fibrous tumors (ISFT). Methods: Ten patients with ISFT proven histopathologically were collected. Four cases had CT data and all cases had MR data. The imaging features and pathological results were retrospectively analyzed. Results: All cases were misdiagnosed as meningioma at pre-operation. All lesions arose from intracranial meninges including 5 lesions above the tentorium, 4 lesions beneath the tentorium and 1 lesion growing around the tentorium. The margins of all the masses were well defined, and 8 lesions presented multilobular shape. CT demonstrated hyerattenuated masses in all 4 lesions, smooth erosion of the basicranial skull in 1 lesion, and punctiform calcification of the capsule in 1 lesion. T 1 WI showed most lesions with isointense or slight hyperintense signals including homogeneous in 4 lesions and heterogeneous in 6 lesions. T 2 WI demonstrated isointense or slight hyperintense in 2 lesions, mixed hypointense and hyperintense signals in 4, cystic portion in 2, and two distinct portion of hyperintense and hypointense signal, so called 'yin-yang' pattern, in 2. Strong enhanced was found in all lesions, especially in 8 lesion with heterogeneous with the low T 2 signal. 'Dural tail' was found in 4 lesions. Conclusions: ISFI has some specific CT and MR features including heterogeneous signal intensity on T 2 WI, strong enhancement of areas with low T 2 signal intensity, slight or no 'dural tail', without skull thickening, and the typical 'yin-yang' pattern. (authors)

  17. Solitary median maxillary central incisor (SMMCI syndrome

    Directory of Open Access Journals (Sweden)

    Hall Roger K

    2006-04-01

    Full Text Available Abstract Solitary median maxillary central incisor syndrome (SMMCI is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s operating in utero about the 35th–38th day(s from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18–22 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated.

  18. Acute solitary localized pneumonia: CT diagnosis

    International Nuclear Information System (INIS)

    Li Tieyi

    1999-01-01

    Objective: To evaluate CT in the differential diagnosis of solitary localized pneumonia. Method: Only plain CT without contrast study was done because of different types of CT scanners weed. There were 25 cases with localized pneumonia with initial diagnosis as suspected peripheral bronchogenic carcinoma. All patients were over forty years of age, 84% 50-80 years, 13(52%) patients were asymptomatic, 5(20%) patients had bloody sputum. Results: The CT features were divided into three patterns: (1) irregular nodule with relatively well-defined margin, ground-glass opacity and a few punctuate high densities. (2) irregular nodule with sharply circumscribed, spiculate border and homogeneous density. (3) regular nodule with relatively well-defined margin, and homogeneous density. The third type was most frequent (60%) with predilection for the dorsal segments of the lower lobes, or the posterior basal segments. Of the 25 patients 3 had operation, the remaining cases were treated as pneumonia, the lesions were resolved in 18(82%) patients in 2-3 weeks. Conclusions: Sometimes it is very difficult to differentiate localized pneumonia from peripheral lung cancer on the basis of clinical presentation and imaging. The spiculate margins of irregular nodule shown on CT could be indeterminate on chest radiography, and as a result chest radiograph is helpful in differential diagnosis of localized pneumonia. Change in size of the lesion as observed at the same cross-section scan, smaller at mediastinal window than at lung window is in favor of localized pneumonia, however, with the exception of alveolar carcinoma, treatment with antibiotic therapy for a period of 2-3 weeks, helps differentiate these diseases

  19. Bed failure induced by internal solitary waves

    Science.gov (United States)

    Rivera-Rosario, Gustavo A.; Diamessis, Peter J.; Jenkins, James T.

    2017-07-01

    The pressure field inside a porous bed induced by the passage of an Internal Solitary Wave (ISW) of depression is examined using high-accuracy numerical simulations. The velocity and density fields are obtained by solving the Dubreil-Jacotin-Long Equation, for a two-layer, continuously stratified water column. The total wave-induced pressure across the surface of the bed is computed by vertically integrating for the hydrostatic and nonhydrostatic contributions. The bed is assumed to be a continuum composed of either sand or silt, with a small amount of trapped gas. Results show variations in pore-water pressure penetrating deeper into more conductive materials and remaining for a prolonged period after the wave has passed. In order to quantify the potential for failure, the vertical pressure gradient is compared against the buoyant weight of the bed. The pressure gradient exceeds this weight for weakly conductive materials. Failure is further enhanced by a decrease in bed saturation, consistent with studies in surface-wave induced failure. In deeper water, the ISW-induced pressure is stronger, causing failure only for weakly conductive materials. The pressure associated with the free-surface displacement that accompanies ISWs is significant, when the water depth is less than 100 m, but has little influence when it is greater than 100 m, where the hydrostatic pressure due to the pycnocline displacement is much larger. Since the pore-pressure gradient reduces the specific weight of the bed, results show that particles are easier for the flow to suspend, suggesting that pressure contributes to the powerful resuspension events observed in the field.

  20. Stochastic resonance modulates neural synchronization within and between cortical sources.

    Directory of Open Access Journals (Sweden)

    Lawrence M Ward

    Full Text Available Neural synchronization is a mechanism whereby functionally specific brain regions establish transient networks for perception, cognition, and action. Direct addition of weak noise (fast random fluctuations to various neural systems enhances synchronization through the mechanism of stochastic resonance (SR. Moreover, SR also occurs in human perception, cognition, and action. Perception, cognition, and action are closely correlated with, and may depend upon, synchronized oscillations within specialized brain networks. We tested the hypothesis that SR-mediated neural synchronization occurs within and between functionally relevant brain areas and thus could be responsible for behavioral SR. We measured the 40-Hz transient response of the human auditory cortex to brief pure tones. This response arises when the ongoing, random-phase, 40-Hz activity of a group of tuned neurons in the auditory cortex becomes synchronized in response to the onset of an above-threshold sound at its "preferred" frequency. We presented a stream of near-threshold standard sounds in various levels of added broadband noise and measured subjects' 40-Hz response to the standards in a deviant-detection paradigm using high-density EEG. We used independent component analysis and dipole fitting to locate neural sources of the 40-Hz response in bilateral auditory cortex, left posterior cingulate cortex and left superior frontal gyrus. We found that added noise enhanced the 40-Hz response in all these areas. Moreover, added noise also increased the synchronization between these regions in alpha and gamma frequency bands both during and after the 40-Hz response. Our results demonstrate neural SR in several functionally specific brain regions, including areas not traditionally thought to contribute to the auditory 40-Hz transient response. In addition, we demonstrated SR in the synchronization between these brain regions. Thus, both intra- and inter-regional synchronization of neural

  1. Synchronizing XPath Views

    DEFF Research Database (Denmark)

    Pedersen, Dennis; Pedersen, Torben Bach

    2004-01-01

    . However, the XML data sources are often independent of the data consumers and may change their schemas without notification, invalidating the XML views defined by the data consumers. This requires the view definitions to be updated to reflect the new structure of the data sources, a process termed view......The increasing availability of XML-based data sources, e.g., for publishing data on the WWW, means that more and more applications (data consumers) rely on accessing and using XML data. Typically, the access is achieved by defining views over the XML data, and accessing data through these views...... synchronization. XPath is the most commonly used language for retrieving parts of XML documents, and is thus an important cornerstone for XML view definitions. This paper presents techniques for discovering schema changes in XML data sources and synchronizing XPath-based views to reflect these schema changes...

  2. LHC synchronization test successful

    CERN Multimedia

    The synchronization of the LHC's clockwise beam transfer system and the rest of CERN's accelerator chain was successfully achieved last weekend. Tests began on Friday 8 August when a single bunch of a few particles was taken down the transfer line from the SPS accelerator to the LHC. After a period of optimization, one bunch was kicked up from the transfer line into the LHC beam pipe and steered about 3 kilometres around the LHC itself on the first attempt. On Saturday, the test was repeated several times to optimize the transfer before the operations group handed the machine back for hardware commissioning to resume on Sunday. The anti-clockwise synchronization systems will be tested over the weekend of 22 August.Picture:http://lhc-injection-test.web.cern.ch/lhc-injection-test/

  3. Programmable synchronous communications module

    International Nuclear Information System (INIS)

    Horelick, D.

    1979-10-01

    The functional characteristics of a programmable, synchronous serial communications CAMAC module with buffering in block format are described. Both bit and byte oriented protocols can be handled in full duplex depending on the program implemented. The main elements of the module are a Signetics 2652 Multi-Protocol Communications Controller, a Zilog Z-808 8 bit microprocessor with PROM and RAM, and FIFOs for buffering

  4. Solitary waves in a magneto-electro-elastic circular rod

    International Nuclear Information System (INIS)

    Xue, C X; Pan, E; Zhang, S Y

    2011-01-01

    A simple nonlinear model is proposed in this paper to study the solitary wave in a circular magneto-electro-elastic rod. Based on the constitutive relation for transversely isotropic piezoelectric and piezomagnetic materials, combined with the differential equations of motion, we derive the longitudinal wave motion equation in a long circular rod. The nonlinearity considered is geometrically associated with the nonlinear normal strain in the longitudinal rod direction and the transverse Poisson's effect is included by introducing the effective Poisson's ratio. The nonlinear solitary wave equation is solved by the Jacobi elliptic function expansion method and numerical examples demonstrate not only the existence of such a wave but also some interesting characteristics of the solitary wave in the rod made of different multiphase coupled materials

  5. Giant solitary trichoepithelioma with desmoplasia on histopathology: An unusual finding

    Directory of Open Access Journals (Sweden)

    Sundeep Chowdhry

    2016-10-01

    Full Text Available Trichoepithelioma is a well-recognized hamartoma of hair germ clinically presenting as solitary or multiple papules. Uncommonly, it may present as a large solitary lesion, termed as giant solitary trichoepithelioma (GST. A 50-year old man presented with a large, pedunculated mass over the root of nose obstructing visual field. It was excised and sent for histopathological examination. H&E staining revealed in addition to characteristic features of trichoepithelioma, a desmoplastic hypocellular stroma. After taking into account the clinical and histopathological features, a diagnosis of GST was made. This case is the first case to the best of authors’ knowledge describing desmoplastic stroma in a case of GST. It is also noteworthy because it reports the largest GST described so far over the nose.

  6. Ulcerative giant solitary trichoepithelioma of scalp: a rare presentation

    Directory of Open Access Journals (Sweden)

    Sundeep Chowdhry

    2016-07-01

    Full Text Available Trichoepithelioma is a trichogenic tumor which arises from the inferior segment of hair follicle epithelium as hamartoma. Giant solitary trichoepithelioma (GST has been defined as a solitary trichoepithelioma with a diameter greater than 2 cm. A 49-year-old female presented with a slow growing skin coloured swelling on the scalp of 8 years duration with recent history of ulceration and occasional bleeding. The local examination revealed a single well defined nodular swelling which was irregular in shape measuring approximately 2 × 2.5 cm. Histopathology from biopsy specimen revealed dark basaloid cells with scanty cytoplasm and darkly stained nucleus arranged in nests with horn cysts lacking high-grade atypia and mitosis, which was consistent with features of trichoepithelioma. Giant solitary trichoepithelioma of scalp is itself a rare entity and the present case is being reported with the additional component of ulceration in the lesion.

  7. An Uncommon Case of Solitary Peripheral Osteoma in the Mandible

    Directory of Open Access Journals (Sweden)

    Rohit Agrawal

    2015-01-01

    Full Text Available Osteoma is a benign osteogenic lesion which is composed of well differentiated mature compact and/or cancellous bone that proliferates continuously. Its prevalence is 4%. Its pathogenesis is still controversial. Solitary peripheral osteoma of craniofacial region is a rare finding. We report a case of 30-year-old female having solitary peripheral osteoma present on the lingual cortex of the left posterior mandible which was initially asymptomatic but now is causing discomfort while chewing and not associated with Gardner’s syndrome. We also laid emphasis on its clinical, differential diagnosis, radiological, surgical, and histopathological features. The aim of this paper is to present an uncommon case of solitary peripheral osteoma in the mandible along with analysis of literature for peripheral osteomas of jaws and to contribute to the knowledge concerning the pathogenesis, differential diagnosis, and management of these lesions.

  8. Public Health and Solitary Confinement in the United States.

    Science.gov (United States)

    Cloud, David H; Drucker, Ernest; Browne, Angela; Parsons, Jim

    2015-01-01

    The history of solitary confinement in the United States stretches from the silent prisons of 200 years ago to today's supermax prisons, mechanized panopticons that isolate tens of thousands, sometimes for decades. We examined the living conditions and characteristics of the populations in solitary confinement. As part of the growing movement for reform, public health agencies have an ethical obligation to help address the excessive use of solitary confinement in jails and prisons in accordance with established public health functions (e.g., violence prevention, health equity, surveillance, and minimizing of occupational and psychological hazards for correctional staff). Public health professionals should lead efforts to replace reliance on this overly punitive correctional policy with models based on rehabilitation and restorative justice.

  9. A solitary fibrous tumor of the retroperitoneum: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Min; Kim, Chong Soo; Lee, Dong Keun; Cho, Baek Hwan [Chonbuk National Univ. College of Medicine, Chunju (Korea, Republic of); Han, Hyun Young [Euljy Mecical School, Seoul (Korea, Republic of)

    1999-01-01

    The solitary fibrous tumor is a rare spindle cell neoplasm of mesodermal origin. It usually arises in the pleura, though has recently been reported in the peritoneum and at nonserosal sites ; it is, however, extremely rare in the retroperitonum. The authors describe one case of a solitary fibrous tumor that occurred as a huge complex mass in the retroperitoneum of an adult. Preenhanced CT scans showed that the mass was sharply delineated from surrounding organs and that tumor density was the same as that of surrounding musculature. Peripheral Calcifications were noted, and postenhanced scans showed intense, gradual enhancement of solid portions of the mass, with nonenhanced cystic portions. Although not specific, solitary fibrous tumors must be included in the differential diagnosis of a large retroperitoneal tumor of complex consistency and with internal calcification.

  10. Numerical Simulation of Cylindrical Solitary Waves in Periodic Media

    KAUST Repository

    Quezada de Luna, Manuel

    2013-07-14

    We study the behavior of nonlinear waves in a two-dimensional medium with density and stress relation that vary periodically in space. Efficient approximate Riemann solvers are developed for the corresponding variable-coefficient first-order hyperbolic system. We present direct numerical simulations of this multiscale problem, focused on the propagation of a single localized perturbation in media with strongly varying impedance. For the conditions studied, we find little evidence of shock formation. Instead, solutions consist primarily of solitary waves. These solitary waves are observed to be stable over long times and to interact in a manner approximately like solitons. The system considered has no dispersive terms; these solitary waves arise due to the material heterogeneity, which leads to strong reflections and effective dispersion.

  11. Diffractons: Solitary Waves Created by Diffraction in Periodic Media

    KAUST Repository

    Ketcheson, David I.

    2015-03-31

    A new class of solitary waves arises in the solution of nonlinear wave equations with constant impedance and no dispersive terms. These solitary waves depend on a balance between nonlinearity and a dispersion-like effect due to spatial variation in the sound speed of the medium. A high-order homogenized model confirms this effective dispersive behavior, and its solutions agree well with those obtained by direct simulation of the variable-coefficient system. These waves are observed to be long-time stable, globally attracting solutions that arise in general as solutions to nonlinear wave problems with periodically varying sound speed. They share some properties with known classes of solitary waves but possess important differences as well.

  12. Digital Synchronizer without Metastability

    Science.gov (United States)

    Simle, Robert M.; Cavazos, Jose A.

    2009-01-01

    A proposed design for a digital synchronizing circuit would eliminate metastability that plagues flip-flop circuits in digital input/output interfaces. This metastability is associated with sampling, by use of flip-flops, of an external signal that is asynchronous with a clock signal that drives the flip-flops: it is a temporary flip-flop failure that can occur when a rising or falling edge of an asynchronous signal occurs during the setup and/or hold time of a flip-flop. The proposed design calls for (1) use of a clock frequency greater than the frequency of the asynchronous signal, (2) use of flip-flop asynchronous preset or clear signals for the asynchronous input, (3) use of a clock asynchronous recovery delay with pulse width discriminator, and (4) tying the data inputs to constant logic levels to obtain (5) two half-rate synchronous partial signals - one for the falling and one for the rising edge. Inasmuch as the flip-flop data inputs would be permanently tied to constant logic levels, setup and hold times would not be violated. The half-rate partial signals would be recombined to construct a signal that would replicate the original asynchronous signal at its original rate but would be synchronous with the clock signal.

  13. Solitary splenic metastasis from ovarian carcinosarcoma: a case report

    Directory of Open Access Journals (Sweden)

    Gillespie Thomas

    2011-02-01

    Full Text Available Abstract Introduction Metastatic tumors to the spleen are rare but are usually found in conjunction with metastasis to other organs. The most common sources of splenic metastasis are breast, lung and colorectal cancers as well as melanoma and ovarian carcinoma. A solitary carcinosarcoma metastasis to the spleen of any origin is very rare. To the best of our knowledge, there are fewer than 30 reported cases of ovarian primary tumors with solitary metastasis to the spleen, and only three solitary primary carcinosarcomas to the spleen have been reported, of which one is female. We present what is, to the best of our knowledge, the first case of a solitary metastatic carcinosarcoma to the spleen arising from a primary ovarian carcinsarcoma. Case presentation A 72-year-old Hispanic woman status post-total abdominal hysterectomy for ovarian carcinosarcoma presented with complaints of early satiety and abdominal pain for the past two months with a 30-lb unintentional weight loss. An initial computed tomographic scan of her abdomen and pelvis revealed a 30 cm × 27 cm splenic mass with displacement of the left kidney, stomach and liver. The patient was found to have a solitary metastatic carcinosarcoma of the spleen with biphasic epithelial (carcinomatous and mesenchymal (sarcomatous elements consistent with carcinosarcoma. Conclusion Carcinosarcoma of the spleen is a rare tumor. Carcinosarcomas are a biphasic neoplasm comprising malignant epithelial and mesenchymal components arising from a stem cell capable of differentiation. They can arise anywhere in the female genital tract, most commonly from the endometrium. Even though it is rare, carcinosarcomas can metastasize to the spleen. This unique case of a solitary splenic metastasis from ovarian carcinosarcoma has particular interest in medicine, especially for the specialties of surgical oncology, pathology and hematology/oncology.

  14. A case of congenital solitary Langerhans cell histiocytoma.

    LENUS (Irish Health Repository)

    Ricciardo, Bernadette

    2012-02-01

    A newborn baby boy was referred to the Paediatric Dermatology Unit with a solitary asymptomatic nodule overlying his right nasolabial fold. Complete physical examination, full blood count, serum chemistry, liver function tests and baseline imaging were unremarkable. Histopathological examination showed an atypical dermal infiltrate of mononuclear cells that stained positive with CD1a and S100. A diagnosis of congenital solitary Langerhans cell histiocytoma was made. The lesion completely resolved by 4 months of age. The baby is now 15 months old and repeat systemic evaluation has remained normal.

  15. Solitary peripheral osteoma of the mandible: Report of 2 cases

    Directory of Open Access Journals (Sweden)

    Sanat Kumar Bhuyan

    2015-01-01

    Full Text Available Osteomas are benign slow-growing lesions. A very few cases of the peripheral type arising from periosteum have been reported. In the facial region, periosteal osteomas mostly occur in the paranasal sinuses; thus, solitary osteomas of the jaws bones are rare. The etiology is unknown although it could be attributed to as a developmental anomaly, due to trauma or infection. Herein, we have reported two cases of large solitary peripheral osteoma discussing the clinical, radiological, and histological features of the lesion located in the buccal and lingual surface in the left posterior part of mandible causing facial asymmetry and the other being asymptomatic.

  16. Solitary cellular neurofibroma of alveolar mucosa unassociated with neurofibromatosis-1

    Directory of Open Access Journals (Sweden)

    Laxmidevi B Lankesh

    2015-01-01

    Full Text Available Neurofibromas (NFs are rare neurogenic tumors of the oral cavity. They can present as solitary, or multiple when associated with neurofibromatosis-1 (NF-1/von Recklinghausen′s disease. Solitary intraoral NFs unassociated with NF-1 are sporadic and mimic any other soft tissue tumors of the oral cavity. Hence, final diagnosis can only be rendered after histopathological examination although they exhibit numerous microscopic variants. They show numerous mast cells and immunopositive for S-100 protein. Here, we are presenting one such case of NF in a 55-year-old male patient.

  17. Solitary schwannoma of sciatic nerve. Diagnosis by CT

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M.; Handa, J. (Shiga Univ. of Medical Science, Ohtsu, Shiga (Japan)); Koyama, T.

    1982-05-01

    A solitary schwannoma of the peripheral nerve may arise sporadically in patients who have no evidence of a genetic predetermination of von Recklinghausen's disease. In the leg, schwannomas usually appear on the flexor aspect, especially near the elbow, wrist and knee, and the feet are usually spared. A solitary schwannoma of the sciatic nerve is very rare as a case of a sciatic pain, and the CT diagnosis of such a lesion has not been previously reported. In the present case, the deeply situated, small lesion was clearly delineated with high resolution CT.

  18. Asymptomatic solitary mediastinal cystic lymphangioma: a rare entity.

    Science.gov (United States)

    Misthos, Panagiotis; Sepsas, Evangelos; Kokotsakis, Ioannis; Skottis, Ion

    2006-12-01

    Solitary mediastinal cystic lymphangioma is an extremely rare tumor-like abnormality of the lymphatic system, of congenital origin. From 1996 to 2003, 4 cases of solitary mediastinal cystic lymphangioma were managed in our department. The clinicopathologic characteristics were recorded and analyzed. The incidence proved to be 1.2% among all cases of mediastinal masses admitted to our department. All patients were asymptomatic, they shared common radiologic features, and all were managed by radical surgical excision. No recurrence or mortality were noted during follow-up ranging from 2 to 7 years. Complete excision of this benign entity has an excellent prognosis.

  19. Solitary wave collisions in the regularized long wave equation

    Directory of Open Access Journals (Sweden)

    Henrik Kalisch

    2013-01-01

    Full Text Available The regularized long-wave equation admits families of positive and negative solitary waves. Interactions of these waves are studied, and it is found that interactions of pairs of positive and pairs of negative solitary waves feature the same phase shift asymptotically as the wave velocities grow large as long as the same amplitude ratio is maintained. The collision of a positive with a negative wave leads to a host of phenomena, including resonance, annihilation and creation of secondary waves. A sharp criterion on the resonance for positive-negative interactions is found.

  20. Solitary solution for the Kadomstev- Petviashvili equation at critical density

    International Nuclear Information System (INIS)

    Elhanbly, A.M.; El-shawey, E.K.; Radwan, N.K.; El-kamash, I.S.

    2011-01-01

    The nonlinear properties of small amplitude electron-acoustic solitary waves ( EASWs) in a homogeneous system of unmagnetized collisionless plasma consisted of a cold electron fluid and isothermal ions with two different temperatures obeying Boltzmann type distributions have been investigated.A reductive perturbation method was employed to obtain the Kadomstev-Petviashvili (KP) equation.At the critical density, the KP equation is not appropriate for describing the system. Hence, a new set of stretched coordinates is considered to derive the modified KP equation. The present investigation can be of relevance to the electrostatic solitary structures observed in various space plasma environments

  1. CT-guided percutaneous treatment of solitary pyogenic splenic abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Pombo, F. [Dept. of Radiology, Hospital Juan Canalejo, La Coruna (Spain); Suarez, I. [Dept. of Radiology, Hospital Juan Canalejo, La Coruna (Spain); Marini, M. [Dept. of Radiology, Hospital Juan Canalejo, La Coruna (Spain); Arrojo, L. [Dept. of Radiology, Hospital Juan Canalejo, La Coruna (Spain); Echaniz, A. [Dept. of Internal Medicine, Hospital Juan Canalejo, La Coruna (Spain)

    1991-08-01

    Six patients with solitary pyogenic splenic abscesses treated by CT-guided percutaneous drainage (by catheter or needle), are presented. There were 3 unilocular, purely intrasplenic abscesses and 3 complex lesions with loculations and perisplenic involvement. Percutaneous drainage and intravenous antibiotics were curative in 4 patients. In the other 2, who had multiloculated abscesses, despite initially successful drainage, splenectomy was performed because of intractable left upper quadrant pain in one case and persistent fever and drainage of pus after 30 days in the other. These patients also developed large, sterile left pleural effusions. Solitary pyogenic splenic abscesses - particularly if uniloculated - can be effectively treated by CT-guided percutaneous drainage. (orig.)

  2. Solitary Eccrine Syringofibroadenoma and Successful Treatment with Cryotherapy.

    Science.gov (United States)

    Ozkaya, Dilek Biyik; Su, Ozlem; Bahalı, Anıl Gülsel; Topukçu, Bugce; Dizman, Didem; Tosuner, Zeynep; Demirkesen, Cuyan; Onsun, Nahide

    2016-05-01

    First described in 1963, eccrine syringofibroadenoma (ESFA) is a rare benign tumor that proliferates with differentiation toward ductal eccrine structures. There are many clinical presentations, including plaques, papules, verrucous plaques, keratotic tumors, and solitary tumors. The age of onset varies, with presentation between 16 and 80 years; however, solitary lesions are seen most commonly in the seventh and eighth decades. Here, we present the case of a 72-year-old woman referred to our outpatient clinic with a nodule on her leg. The histopathology result was ESFA. The lesion regressed after six cryotherapy sessions. Physicians should consider the possibility of ESFA and must remember its malignant potential in elderly patients.

  3. A Solitary Fibrous Tumor of the Pleura Revealed by Hiccups

    Directory of Open Access Journals (Sweden)

    A. Chafik

    2011-01-01

    Full Text Available Solitary fibrous tumors of the pleura are rare and benign primary localized tumors; they possess a malignant potential and thus should be excised. We report a case of a 43-year-old woman, who had suffered for 5 years from right basithoracic pain associated with progressive dyspnea and persistent hiccups during the last 6 months. We have not found any similar case in the literature. Further testing after excision by thoracotomy revealed a solitary fibrous pleural tumor. A brief discussion of the clinical presentation and incidence of these tumors is included.

  4. Solitary-wave propagation and interactions for a sixth-order generalized Boussinesq equation

    Directory of Open Access Journals (Sweden)

    Bao-Feng Feng

    2005-01-01

    based on the phase plane analysis around the equilibrium point, is used to construct the solitary-wave solutions for this nonintegrable equation. A symmetric three-level implicit finite difference scheme with a free parameter θ is proposed to study the propagation and interactions of solitary waves. Numerical simulations show the propagation of a single solitary wave of SGBE, and two solitary waves pass by each other without changing their shapes in the head-on collisions.

  5. The role of cerebral blood flow gradient in peritumoral edema for differentiation of glioblastomas from solitary metastatic lesions.

    Science.gov (United States)

    Lin, Lin; Xue, Yunjing; Duan, Qing; Sun, Bin; Lin, Hailong; Huang, Xinming; Chen, Xiaodan

    2016-10-18

    Differentiation of glioblastomas from solitary brain metastases using conventional MRI remains an important unsolved problem. In this study, we introduced the conception of the cerebral blood flow (CBF) gradient in peritumoral edema-the difference in CBF values from the proximity of the enhancing tumor to the normal-appearing white matter, and investigated the contribution of perfusion metrics on the discrimination of glioblastoma from a metastatic lesion. Fifty-two consecutive patients with glioblastoma or a solitary metastatic lesion underwent three-dimensional arterial spin labeling (3D-ASL) before surgical resection. The CBF values were measured in the peritumoral edema (near: G1; Intermediate: G2; Far: G3). The CBF gradient was calculated as the subtractions CBFG1 -CBFG3, CBFG1 - CBFG2 and CBFG2 - CBFG3. A receiver operating characteristic (ROC) curve analysis was used to seek for the best cutoff value permitting discrimination between these two tumors. The absolute/related CBF values and the CBF gradient in the peritumoral regions of glioblastomas were significantly higher than those in metastases(P edema appears to be a more promising ASL perfusion metrics in differentiating high grade glioma from a solitary metastasis.

  6. Radiosurgery without whole brain radiotherapy in melanoma brain metastases

    International Nuclear Information System (INIS)

    Grob, J.J.; Regis, J.; Laurans, R.; Delaunay, M.; Wolkenstein, P.; Paul, K.; Souteyrand, P.; Koeppel, M.C.; Murraciole, X.; Perragut, J.C.; Bonerandi, J.J.

    1998-01-01

    To evaluate the effectiveness of radiosurgery without whole brain radiotherapy in the palliative treatment of melanoma brain metastases, we retrospectively assessed the results in 35 patients: 4 with a solitary brain metastasis, 13 with a single brain metastasis and metastases elsewhere and 18 with multiple brain metastases. The local control rate was 98.2% (55/56 metastases) at 3 months. Median survival was 22 months in patients with a solitary brain metastasis, 7.5 months in patients with a single brain metastasis and metastases elsewhere, and 4 months in patients with multiple brain metastases. Complications were unusual and surgery was required in 2 of 35 patients. These results show for the first time that melanoma patients with a unique brain metastasis with or without metastases elsewhere clearly benefit from tumour control easily obtained by radiosurgery. Although the comparison of radiosurgery with surgery and/or whole brain radiotherapy cannot be adequately addressed, radiosurgery alone seems to provide similar results with lower morbidity and impact on quality of life. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Synchronized Drumming Enhances Activity in the Caudate and Facilitates Prosocial Commitment - If the Rhythm Comes Easily

    NARCIS (Netherlands)

    Kokal, Idil; Engel, Annerose; Kirschner, Sebastian; Keysers, Christian

    2011-01-01

    Why does chanting, drumming or dancing together make people feel united? Here we investigate the neural mechanisms underlying interpersonal synchrony and its subsequent effects on prosocial behavior among synchronized individuals. We hypothesized that areas of the brain associated with the

  8. Cramped synchronized general movements in preterm infants as an early marker for cerebral palsy

    NARCIS (Netherlands)

    Ferrari, F; Cioni, G; Einspieler, C; Roversi, MF; Bos, AF; Paolicelli, PB; Ranzi, A; Prechtl, HFR

    Objective: To ascertain whether specific abnormalities (ie, cramped synchronized general movements [GMs]) can predict cerebral palsy and the severity of later motor impairment in preterm infants affected by brain lesions. Design: Traditional neurological examination was performed, and GMs were

  9. Solitary Secondary Malignant Melanoma of Clavicle Two Years after Enuclation for Ocular Melanoma

    Directory of Open Access Journals (Sweden)

    Halil Tozum

    2013-01-01

    Full Text Available Solitary metastasis of uveal melanoma to bone is extremely rare and usually associated with other organ involvement. We present a rare case of an ocular melanoma patient presenting with solitary metastasis to the clavicle two years after enucleation, without any other organ involvement. In this report, we tried to present our treatment strategy for the solitary metastasis of bone.

  10. The transient ladder synchronization of chaotic systems

    International Nuclear Information System (INIS)

    Chen, H.-K.; Sheu, L.-J.

    2006-01-01

    A new type for chaotically synchronizing systems, transient ladder chaos synchronization, is proposed in this Letter. For some physical systems, chaotic synchronization is possible in only some of the variables. It is shown that, for the non-synchronizing variable, synchronization up to a constant difference for t 1 = 2 is possible. The transient ladder chaos synchronization and anti-synchronization are illustrated by using two identical chaotic Froude pendulums. Numerical simulations are shown for demonstration

  11. Control of synchronous motors

    CERN Document Server

    Louis, Jean-Paul

    2013-01-01

    Synchronous motors are indubitably the most effective device to drive industrial production systems and robots with precision and rapidity. Their control law is thus critical for combining at the same time high productivity to reduced energy consummation. As far as possible, the control algorithms must exploit the properties of these actuators. Therefore, this work draws on well adapted models resulting from the Park's transformation, for both the most traditional machines with sinusoidal field distribution and for machines with non-sinusoidal field distribution which are more and more used in

  12. Psychic energy and synchronicity.

    Science.gov (United States)

    Zabriskie, Beverley

    2014-04-01

    Given Jung's interest in physics' formulations of psychic energy and the concept of time, overlaps and convergences in the themes addressed in analytical psychology and in quantum physics are to be expected. These are informed by the active intersections between the matter of mind and mindfulness re matter. In 1911, Jung initiated dinners with Einstein. Jung's definition of libido in the pivotal 1912 Fordham Lectures reveals the influence of these conversations. Twenty years later, a significant period in physics, Wolfgang Pauli contacted Jung. Their collaboration led to the theory of synchronicity. © 2014, The Society of Analytical Psychology.

  13. Logarithmically slow onset of synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Benkoe, Gil; Jensen, Henrik Jeldtoft [Institute for Mathematical Sciences, Imperial College London, 53 Prince' s Gate, South Kensington Campus, SW7 2PG, London (United Kingdom)], E-mail: g.benkoe@imperial.ac.uk, E-mail: h.jensen@imperial.ac.uk

    2010-04-23

    The transient of a synchronizing system is investigated, considering synchronization as a relaxation phenomenon. The stepwise establishment of synchronization is studied in the system of dynamically coupled maps introduced by Ito and Kaneko (2001 Phys. Rev. Lett. 88 028701, 2003 Phys. Rev. E 67 046226), where the plasticity of dynamical couplings might be relevant in the context of neuroscience. Logarithmically slow dynamics in the transient of a fully deterministic dynamical system are shown to occur.

  14. Solitary wave solution to a singularly perturbed generalized Gardner ...

    Indian Academy of Sciences (India)

    2015-11-27

    Home; Journals; Pramana – Journal of Physics; Volume 88; Issue 4. Solitary wave solution to a singularly perturbed generalized ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: ...

  15. Reconstructive surgery in eight children with solitary kidneys

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens

    1989-01-01

    Within a 10-year period reconstructive urinary tract surgery has been carried out in eight children with solitary kidneys. The children were 0-5 years old. Six had unilateral renal agenesis and two had unilateral multicystic kidney. In five children ureteroneocystostomy was performed, in two...

  16. Solitary wave solution to a singularly perturbed generalized Gardner ...

    Indian Academy of Sciences (India)

    2017-03-24

    Mar 24, 2017 ... which is one model in plasma physics and solid physics. [3]. Hamdi et al [4] obtained an exact solitary wave solution to eq. (1.2). They also derived three conserva- tion laws and three invariants of motion for eq. (1.2). [5]. Antonova and Biswas [6] exploited the soliton perturbation theory to eq. (1.2) with γ = 1.

  17. Observations of Solitary Structures in a Magnetized, Plasma Loaded Waveguide

    DEFF Research Database (Denmark)

    Lynov, Jens-Peter; Michelsen, Poul; Pécseli, Hans

    1979-01-01

    Two types of solitary structure were investigated experimentally and numerically in a magnetized, plasma-loaded waveguide. One was identified as an ordinary KdV soliton and its properties were investigated with particular attention to the damping by resonant particles. The other type of pulse was...

  18. Solitary wave solutions of two-dimensional nonlinear Kadomtsev ...

    Indian Academy of Sciences (India)

    2017-09-13

    Sep 13, 2017 ... Home; Journals; Pramana – Journal of Physics; Volume 89; Issue 3. Solitary wave solutions of ... Nonlinear two-dimensional Kadomtsev–Petviashvili (KP) equation governs the behaviour of nonlinear waves in dusty plasmas with variable dust charge and two temperature ions. By using the reductive ...

  19. The frequency of carcinoma in solitary thyroid nodules and in ...

    African Journals Online (AJOL)

    Muhimbili Medical Centre, Dar es Salaam was made to determine the frequency of malignancy in patients with solitary non-toxic thyroid nodule (STN) and in those with multinodular goitre (MNG). There were 60 cases of STN and. 178 with MNG. Nodular goitre was found to be predominantly a disease of females with sex.

  20. African Journal of Science and Technology (AJST) SOLITARY ...

    African Journals Online (AJOL)

    Department of Physics, University of Yaounde 1, Yaoundé, Cameroon. E-mail: lenouo@yahoo.fr. ABSTRACT: Weakly nonlinear .... By using a multiple scale method, we can write a stream function ψ in the form of a ..... applicable to description of Rossby solitary waves. This requires the choice of additional wind speed C1.

  1. Dust acoustic solitary and shock waves in strongly coupled dusty ...

    Indian Academy of Sciences (India)

    between nonlinear and dispersion effects can result in the formation of symmetrical solitary waves. Also shock ... et al have studied the effect of nonadiabatic dust charge variation on the nonlinear dust acoustic wave with ..... Figure 5 presents the border between oscillatory- and monotonic-type shock waves as functions of ...

  2. Acute inflammation at a mandibular solitary horizontal incompletely impacted molar

    Directory of Open Access Journals (Sweden)

    Minoru Yamaoka

    2009-04-01

    Full Text Available Minoru Yamaoka, Yusuke Ono, Masahide Ishizuka, Yoko Hasumi-Nakayama, Ryosuke Doto, Kouichi Yasuda, Takashi Uematsu, Kiyofumi FurusawaOral and Maxillofacial Surgery, Matsumoto Dental University School of Dentistry, Shiojiri, Nagano, JapanAbstract: Acute inflammation is frequently seen in the elderly around incompletely impacted molars located apart from molars or premolars. To identify the factors causing acute inflammation in the solitary molars without second molars or without second and first molars, ages of patients and rates of acute inflammation in 75 horizontal incompletely impacted mandibular molars in contact or not in contact with molars in subjects 41 years old or older were studied using orthopantomographs. Acute inflammation was seen in nine third molars out of 48 third molars in contact with second molars (18.8%, whereas acute inflammation was seen in 11 molars out of 19 solitary molars without second molars or without first and second molars (57.9% (p < 0.01. The mean age of 48 subjects with third molars in contact with the second molar was 50.42 ± 7.62 years, and the mean age of 19 subjects with isolated molars was 65.16 ± 10.41 years (p < 0.0001. These indicate that a solitary horizontal incompletely impacted molar leads more frequently to acute inflammation along with aging due to possible bone resorption resulting from teeth loss.Keywords: mandible, third molar, impaction, elderly, acute inflammation, solitary molar

  3. Periodic and solitary wave solutions of cubic–quintic nonlinear ...

    Indian Academy of Sciences (India)

    physics pp. 1253–1258. Periodic and solitary wave solutions of cubic–quintic nonlinear reaction-diffusion equation with variable convection coefficients. S B BHARDWAJ1,2,∗ ... 3Department of Mathematics, National Institute of Technology, Delhi 110 040, India. 4Department of .... 3.1 Fractional transform soliton solutions.

  4. An efficient algorithm for computation of solitary wave solutions to ...

    Indian Academy of Sciences (India)

    2017-09-08

    Sep 8, 2017 ... Nonlinear mathematical problems and their solutions attain much attention in solitary waves. In soliton theory, an efficient tool to attain various types of soliton solutions is the exp ( − φ ( ζ ) ) -expansion technique. This article is devoted to find exact travelling wave solutions of Drinfeld–Sokolov equation via a ...

  5. Is DNA a nonlinear dynamical system where solitary conformational ...

    Indian Academy of Sciences (India)

    Unknown

    DNA is considered as a nonlinear dynamical system in which solitary conformational waves can be excited. The history of the approach, the main results, and arguments in favour and against are presented. Perspectives are discussed pertaining to studies of DNA's nonlinear properties. 1. Introduction. In recent years, many ...

  6. Accelerated processing of solitary and clustered abasic site DNA ...

    Indian Academy of Sciences (India)

    The stimulatory effect of the aqueous extract of G. lucidum, a basidiomycetes class fungus in the APE1-enzyme-mediated processing of solitary and bistranded clustered abasic sites DNA damages is presented. Abasic sites are considered the most common type of DNA damage lesions. Our study shows enhanced activity ...

  7. An efficient algorithm for computation of solitary wave solutions to ...

    Indian Academy of Sciences (India)

    KAMRAN AYUB

    2017-09-08

    Sep 8, 2017 ... exact solitary wave solutions of nonlinear differential equations is a great achievement. In nonlinear physical sciences, an essential contribution is of exact solutions and because of this we can study physical behaviours and discus more features of the problem which give direction to more applications.

  8. Interaction of solitary pulses in single mode optical fibres | Usman ...

    African Journals Online (AJOL)

    Two solitary waves launched, by way of incidence, into an optical fibre from a single pulse if the pulses are in-phase as understood from results of inverse scattering transform method applied to the cubic nonlinear Schrödinger equations, (CNLSE\\'s). The single CNLSE is then understood to describe evolution of coupled ...

  9. Solitary Extramedullary Plasmacytoma of the Cricoid Cartilage—Case Report

    Directory of Open Access Journals (Sweden)

    Simone Krebs

    2017-11-01

    Full Text Available Solitary plasmacytoma (SP is an extremely rare form of hematologic malignancy that can be classified as solitary bone plasmacytoma or solitary extramedullary plasmacytoma. Here, we report a patient who presented with progressive shortness of breath and foreign body sensation in his throat. Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT demonstrated an abnormal FDG-avid soft tissue mass arising from the larynx involving the cricoid cartilage without additional suspicious lesions. Histology revealed an abundance of plasma cells; immunohistochemistry was positive for CD138 expression and lambda chains, and negative for CD20. Comprehensive imaging studies and panendoscopy of the ENT tract confirmed solitary disease involvement. Following additional systemic work-up, a diagnosis of extramedullary plasmacytoma was rendered. The patient underwent definitive radiotherapy using intensity-modulated radiation therapy (total dose of 46 Gy, divided in 23 fractions of 200 cGy. Serial PET/CT showed the stepwise resolution of abnormal FDG uptake and resolution of the cricoid cartilage lesion. With 22 months of follow-up, the patient remains free of disease. We describe the rare case of SP presenting as a FDG-avid hypermetabolic soft tissue mass in the cricoid cartilage, which should be considered in the differential diagnosis of laryngeal tumors. Of note, SP is radiosensitive; favorable outcome can be expected once treated with doses of 40–50 Gy. FDG PET/CT is helpful in diagnosis and response assessment for this disease.

  10. Quantum ion-acoustic solitary waves in weak relativistic plasma

    Indian Academy of Sciences (India)

    A linear dispersion relation is also obtained taking into account the relativistic effect. The properties of quantum ion-acoustic solitary waves, obtained from the deformed KdV equation, are studied taking into account the quantum mechanical effects in the weak relativistic limit. It is found that relativistic effects significantly ...

  11. Electron-acoustic solitary waves in the Earth's inner magnetosphere

    Science.gov (United States)

    Dillard, C. S.; Vasko, I. Y.; Mozer, F. S.; Agapitov, O. V.; Bonnell, J. W.

    2018-02-01

    The broadband electrostatic turbulence observed in the inner magnetosphere is produced by large-amplitude electrostatic solitary waves of generally two types. The solitary waves with symmetric bipolar parallel (magnetic field-aligned) electric field are electron phase space holes. The solitary waves with highly asymmetric bipolar parallel electric field have been recently shown to correspond to the electron-acoustic plasma mode (existing due to two-temperature electron population). Through theoretical and numerical analysis of hydrodynamic and modified Korteweg-de Vries equations, we demonstrate that the asymmetric solitary waves appear due to the steepening of initially quasi-monochromatic electron-acoustic perturbation arrested at some moment by collisionless dissipation (Landau damping). The typical steepening time is found to be from a few to tens of milliseconds. The steepening of the electron-acoustic waves has not been reproduced in self-consistent kinetic simulations yet, and factors controlling the formation of steepened electron-acoustic waves, rather than electron phase space holes, remain unclear.

  12. Accelerated processing of solitary and clustered abasic site DNA ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... The stimulatory effect of the aqueous extract of G. lucidum, a basidiomycetes class fungus in the APE1-enzyme-mediated processing of solitary and bistranded clustered abasic sites DNA damages is presented. Abasic sites are considered the most common type of DNA damage lesions. Our study shows ...

  13. Novel antimicrobial peptides from the venom of solitary bees

    Czech Academy of Sciences Publication Activity Database

    Čeřovský, Václav; Cvačka, Josef; Voburka, Zdeněk; Hovorka, Oldřich; Slaninová, Jiřina; Fučík, Vladimír; Bednárová, Lucie

    2008-01-01

    Roč. 14, č. 8 (2008), s. 92-92 ISSN 1075-2617. [European Peptide Symposium /30./. 31.08.2008-05.09.2008, Helsinki] Institutional research plan: CEZ:AV0Z40550506 Keywords : antimicrobial peptides * solitary bees * melectin * isolation and characterization Subject RIV: CC - Organic Chemistry

  14. An efficient algorithm for computation of solitary wave solutions to ...

    Indian Academy of Sciences (India)

    KAMRAN AYUB

    2017-09-08

    Sep 8, 2017 ... Abstract. Nonlinear mathematical problems and their solutions attain much attention in solitary waves. In soliton theory, an efficient tool to attain various types of soliton solutions is the exp(−ϕ(ζ))-expansion technique. This article is devoted to find exact travelling wave solutions of Drinfeld–Sokolov equation ...

  15. Giant solitary fibrous tumor of the lung: A case report

    OpenAIRE

    Xiao, Ping; Sun, Linlin; Zhong, Diansheng; Lian, Linjuan; Xu, Dongbo

    2014-01-01

    A solitary fibrous tumor arising from the lung parenchyma is rarely described. Here, we present the clinical, imaging, and histological features of a case of a 54-year-old woman with an incidental lung mass of the right lower lobe on a chest radiograph.

  16. Measurement and modeling of bed shear stress under solitary waves

    Digital Repository Service at National Institute of Oceanography (India)

    Jayakumar, S.; Guard, P.A.; Baldock, T.E.

    Direct measurements of bed shear stresses (using a shear cell apparatus) generated by non-breaking solitary waves are presented. The measurements were carried out over a smooth bed in laminar and transitional flow regimes (~ 10 sup (4) < R sub (e...

  17. Solitary pulmonary nodule: radiologic features and diagnostic approach

    International Nuclear Information System (INIS)

    Rodriguez Cambronero, Luis Enrique

    2012-01-01

    A literature review is conducted on the solitary pulmonary nodule, to determine the diagnostic methods and specific characteristics. The diagnostic methods used have been: chest radiography, computed tomography, positron emission tomography and magnetic resonance imaging. The radiological features are defined: location, size, definition of contours or edges (margins), densitometric and attenuation characteristics, cavitation, air bronchogram, growth, doubling time, satellite nodules, nutrient vessels [es

  18. Solitary wave and periodic wave solutions for Burgers, Fisher ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 85; Issue 1. Solitary wave and periodic wave solutions for Burgers, Fisher, Huxley and combined forms of these equations by the (′/)-expansion method. Jalil Manafian Mehrdad Lakestani. Volume 85 Issue 1 July 2015 pp 31-52 ...

  19. Is DNA a nonlinear dynamical system where solitary conformational ...

    Indian Academy of Sciences (India)

    Unknown

    DNA is considered as a nonlinear dynamical system in which solitary conformational waves can be excited. The history of the approach, the ..... nucleotides; K is the coupling constant along each strand;. R0 is the radius of DNA; a is .... Let us note that the system of equations (12)–(17) can be divided into two independent ...

  20. Periodic and solitary wave solutions of cubic–quintic nonlinear ...

    Indian Academy of Sciences (India)

    odic, double-kink, bell and antikink-type solutions for cubic–quintic nonlinear reaction-diffusion equation are extracted. Such solutions can be used to explain various biological and physical phenomena. Keywords. Variable coefficient reaction-diffusion equation; solitary wave solution; cubic–quintic nonlinearity. PACS No.

  1. Periodic and solitary wave solutions of cubic–quintic nonlinear ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 6. Periodic and solitary wave solutions of cubic–quintic nonlinear reaction-diffusion equation with variable convection coefficients. BHARDWAJ S B SINGH RAM MEHAR SHARMA KUSHAL MISHRA S C. Regular Volume 86 Issue 6 June 2016 pp 1253-1258 ...

  2. Quantum ion-acoustic solitary waves in weak relativistic plasma

    Indian Academy of Sciences (India)

    Abstract. Small amplitude quantum ion-acoustic solitary waves are studied in an unmagnetized two- species relativistic quantum plasma system, comprised of electrons and ions. The one-dimensional quantum hydrodynamic model (QHD) is used to obtain a deformed Korteweg–de Vries (dKdV) equation by reductive ...

  3. Sonographic Appearance of a Solitary Intramuscular Cysticercosis: A Case Report

    International Nuclear Information System (INIS)

    Moon, Ju Hee; Joo, Seung Ho; Shim, Joo Eun; Kim, Yee Jeong; Oh, Hyun Cheol; Kim, Tae Hwan

    2009-01-01

    The development of antiparasitic drugs and public health strategies has reduced the prevalence of cysticercosis in South Korea. In contrast, the disease is still endemic in Southeast Asia. The influx of immigrants from endemic areas has been on the increase. We report the sonographic and pathological findings of cysticercosis that presented as an intramuscular solitary mass in a 27-year-old Philippine woman

  4. Grid Synchronization for Distributed Generations

    DEFF Research Database (Denmark)

    Peyghami, Saeed; Mokhtari, Hossein; Blaabjerg, Frede

    2017-01-01

    Distributed generators (DGs) like photovoltaic arrays, wind turbines, and fuel cell modules, as well as distributed storage (DS) units introduce some advantages to the power systems and make it more reliable, flexible, and controllable in comparison with the conventional power systems. Grid...... of interfaces needs to be synchronized with the grid or microgird, and hence, a precise synchronization algorithm—mostly based on phase-locked loop—is required to estimate the phase angle and frequency of the voltage at the coupling point. Unlike synchronous generators, in power electronic interfaced DGs...... grid. Therefore, the synchronization is an important issue in DGs to have a stable and reliable operation....

  5. Percutaneous nephrolithotomy in patients with a solitary kidney

    Directory of Open Access Journals (Sweden)

    Tufan Süelözgen

    2014-12-01

    Full Text Available Material and method: The results of percutaneous nephrolithotomy applied to 716 patients in our clinic between January 2008 and January 2014 were retrospectively evaluated. Age, gender, urinary calculi size (mm2, urinary calculi localization, ESWL history, operation duration (min, fluoroscopy duration (sec, access type, reason of solitary kidney, hemoglobin drawdown (g/dl and operation success of the patients with a solitary kidney were recorded. The patients having no preoperative and postoperative non contrast abdominal tomography were excluded from the study. Results: Fifteen of nineteen patients (79% were men and 4 of them (21% were women. The average age of the patients was 42.52 ± 16.72 (14-72. Ten patients had anatomical solitary kidney and nine patients had physiological solitary kidney. In fact counter kidney was non functional in 9 patients (47% whereas there was agenesis in 2 (11% and outcome of nephrectomy in 8 (42% patients. In our study, presence of residual stone less than 4 mm at 1st month postoperative non contrast abdominal tomography was accepted as a successful result and accordingly our success rate was detected as 84%. Mean urinary calculi size was 405 ± 252.9 mm2; urinary calculi localization was pelvic, lower pole, upper-middle pole, middle-lower pole and staghorn in 11 (58%, 4 (21%, 1 (5%, 1 (5% and 1 (5% patients, respectively; previous ESWL history was 16%; operation duration was 55.47-± 28.1 min and fluoroscopy duration 131.10 ± 87.6 sec; access type was subcostal in 79%, supracostal in 10.5% and multiple in 10.5%; hemoglobin drawdown was 1.75 ± 0.97 mg/dl. Conclusions: PNL can be effectively and safely administered for the treatment of solitary kidney. In the treatment of large urinary calculi in patients with a solitary kidney, PNL has some advantages such as short surgery duration, less complication, acceptable hemoglobin drawdown and high success rates. According to our study, PNL operation in patients with a

  6. Interaction of synchronized dynamics in cortex and basal ganglia in Parkinson's disease.

    Science.gov (United States)

    Ahn, Sungwoo; Zauber, S Elizabeth; Worth, Robert M; Witt, Thomas; Rubchinsky, Leonid L

    2015-09-01

    Parkinson's disease pathophysiology is marked by increased oscillatory and synchronous activity in the beta frequency band in cortical and basal ganglia circuits. This study explores the functional connections between synchronized dynamics of cortical areas and synchronized dynamics of subcortical areas in Parkinson's disease. We simultaneously recorded neuronal units (spikes) and local field potentials (LFP) from subthalamic nucleus (STN) and electroencephalograms (EEGs) from the scalp in parkinsonian patients, and analysed the correlation between the time courses of the spike-LFP synchronization and inter-electrode EEG synchronization. We found the (non-invasively obtained) time course of the synchrony strength between EEG electrodes and the (invasively obtained) time course of the synchrony between spiking units and LFP in STN to be weakly, but significantly, correlated with each other. This correlation is largest for the bilateral motor EEG synchronization, followed by bilateral frontal EEG synchronization. Our observations suggest that there may be multiple functional modes by which the cortical and basal ganglia circuits interact with each other in Parkinson's disease: not only may synchronization be observed between some areas in cortex and the basal ganglia, but also synchronization within cortex and within basal ganglia may be related, suggesting potentially a more global functional interaction. More coherent dynamics in one brain region may modulate or activate the dynamics of another brain region in a more powerful way, causing correlations between changes in synchrony strength in the two regions. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  7. FPGA based fast synchronous serial multi-wire links synchronization

    Science.gov (United States)

    Pozniak, Krzysztof T.

    2013-10-01

    The paper debates synchronization method of multi-wire, serial link of constant latency, by means of pseudo-random numbers generators. The solution was designed for various families of FPGA circuits. There were debated synchronization algorithm and functional structure of parameterized transmitter and receiver modules. The modules were realized in VHDL language in a behavioral form.

  8. Concordant DNA Methylation in Synchronous Colorectal Carcinomas

    Science.gov (United States)

    Konishi, Kazuo; Shen, Lanlan; Jelinek, Jaroslav; Watanabe, Yoshiyuki; Ahmed, Saira; Kaneko, Kazuhiro; Kogo, Mari; Takano, Toshihumi; Imawari, Michio; Hamilton, Stanley R.; Issa, Jean-Pierre J.

    2012-01-01

    Epigenetic changes have been proposed as mediators of the field defect in colorectal carcinogenesis, which has implications for risk assessment and cancer prevention. As a test of this hypothesis, we evaluated the methylation status of eight genes (MINT1, 2, 31, MLH1, p16, p14, MGMT, and ESR1), as well as BRAF and KRAS mutations, in 57 multiple colorectal neoplasias (M-CRN) and compared these to 69 solitary colorectal cancers (S-CRC). There were no significant differences in methylation between M-CRNs and S-CRCs except for p14 and MGMT that was significantly higher in M-CRNs than S-CRCs (16.1% versus 9.3%; 26.5% versus 17.3%, respectively; P < 0.05). We found significant (P < 0.05) correlations for MINT1 (r = 0.8), p16 (r = 0.8), MLH1 (r = 0.9), and MGMT (r = 0.6) methylation between tumors pairs of the same site (proximal/proximal and distal/distal). KRAS showed no concordance in mutations. BRAF mutation showed concordance in proximal site pairs but was discordant in different site pairs. Histologically, eight of 10 paired cancers with similar locations were concordant for a cribriform glandular configuration. We conclude that synchronous colorectal tumors of the same site are highly concordant for methylation of multiple genes, BRAF mutations, and a cribriform glandular configuration, all consistent with a patient-specific predisposition to particular subtypes of colorectal cancers. Screening for and secondary prevention of colon cancer should take this fact into account. PMID:19737982

  9. Delayed feedback control of bursting synchronization in a scale-free neuronal network.

    Science.gov (United States)

    Batista, C A S; Lopes, S R; Viana, R L; Batista, A M

    2010-01-01

    Several neurological diseases (e.g. essential tremor and Parkinson's disease) are related to pathologically enhanced synchronization of bursting neurons. Suppression of these synchronized rhythms has potential implications in electrical deep-brain stimulation research. We consider a simplified model of a neuronal network where the local dynamics presents a bursting timescale, and the connection architecture displays the scale-free property (power-law distribution of connectivity). The networks exhibit collective oscillations in the form of synchronized bursting rhythms, without affecting the fast timescale dynamics. We investigate the suppression of these synchronized oscillations using a feedback control in the form of a time-delayed signal. We located domains of bursting synchronization suppression in terms of perturbation strength and time delay, and present computational evidence that synchronization suppression is easier in scale-free networks than in the more commonly studied global (mean-field) networks.

  10. The Nucleus of the Solitary Tract and the coordination of respiratory and sympathetic activities

    Directory of Open Access Journals (Sweden)

    Daniel B. Zoccal

    2014-06-01

    Full Text Available It is well known that breathing introduces rhythmical oscillations in the heart rate and arterial pressure levels. Sympathetic oscillations coupled to the respiratory activity have been suggested as an important homeostatic mechanism optimizing tissue perfusion and blood gas uptake/delivery. This respiratory-sympathetic coupling is strengthened in conditions of blood gas challenges (hypoxia and hypercapnia as a result of the synchronized activation of brainstem respiratory and sympathetic neurons, culminating with the emergence of entrained cardiovascular and respiratory reflex responses. Studies have proposed that the ventrolateral region of the medulla oblongata is a major site of synaptic interaction between respiratory and sympathetic neurons. However, other brainstem regions also play a relevant role in the patterning of respiratory and sympathetic motor outputs. Recent findings suggest that the neurons of the nucleus of the solitary tract (NTS, in the dorsal medulla, are essential for the processing and coordination of respiratory and sympathetic responses to hypoxia. The NTS is the first synaptic station of the cardiorespiratory afferent inputs, including peripheral chemoreceptors, baroreceptors and pulmonary stretch receptors. The synaptic profile of the NTS neurons receiving the excitatory drive from afferent inputs is complex and involves distinct neurotransmitters, including glutamate, ATP and acetylcholine. In the present review we discuss the role of the NTS circuitry in coordinating sympathetic and respiratory reflex responses. We also analyze the neuroplasticity of NTS neurons and their contribution for the development of cardiorespiratory dysfunctions, as observed in neurogenic hypertension, obstructive sleep apnea and metabolic disorders.

  11. Exploiting Schemas in Data Synchronization

    DEFF Research Database (Denmark)

    Foster, J. Nathan; Greenwald, Michael B.; Kirkegaard, Christian

    2005-01-01

    Increased reliance on optimistic data replication has led to burgeoning interest in tools and frameworks for disconnected updates to replicated data.We have implemented a generic synchronization framework, called HARMONY, that can be used to build state-based synchronizers for a wide variety...

  12. Exploiting Schemas in Data Synchronization

    DEFF Research Database (Denmark)

    Foster, J. Nathan; Greenwald, Michael B.; Kirkegaard, Christian

    2005-01-01

    Increased reliance on optimistic data replication has led to burgeoning interest in tools and frameworks for disconnected updates to replicated data.We have implemented a generic synchronization framework, called HARMONY, that can be used to build state-based synchronizers for a wide variety of t...

  13. Synchronizing clocks in distributed networks

    NARCIS (Netherlands)

    Xia, Weiguo; Cao, Ming

    2011-01-01

    Very recently it has been shown that clocks in distributed networks cannot be synchronized precisely even in idealized situations when asymmetric delays are present [1]. In this paper by determining the clock synchronization errors in the similar settings of the impossibility result just mentioned,

  14. Synchronizing clocks in distributed networks

    NARCIS (Netherlands)

    Xia, Weiguo; Cao, Ming

    2011-01-01

    While various time synchronization protocols for clocks in wired and/or wireless networks are under development, recently it has been shown by Freris, Graham and Kumar that clocks in distributed networks cannot be synchronized precisely even in idealized situations. In this paper by determining the

  15. Digital synchronization and communication techniques

    Science.gov (United States)

    Lindsey, William C.

    1992-01-01

    Information on digital synchronization and communication techniques is given in viewgraph form. Topics covered include phase shift keying, modems, characteristics of open loop digital synchronizers, an open loop phase and frequency estimator, and a digital receiver structure using an open loop estimator in a decision directed architecture.

  16. Benefits of Synchronous Online Courses

    Science.gov (United States)

    Moser, Scott; Smith, Phil

    2015-01-01

    Most online courses are offered as "asynchronous" courses and have no real-time contact with students. The Synchronous online alternative provides normal scheduled class time and allows students to login to a virtual online classroom with the instructor. We provide an overview of two different platforms for hosting synchronous classes…

  17. Business cycle synchronization in Europe

    DEFF Research Database (Denmark)

    Bergman, Ulf Michael; Jonung, Lars

    2011-01-01

    In this paper we study business cycle synchronization in the three Scandinavian countries Denmark, Norway and Sweden prior to, during and after the Scandinavian Currency Union 1873–1913. We find that the degree of synchronization tended to increase during the currency union, thus supporting earlier...

  18. Synchronization dynamics of two different dynamical systems

    International Nuclear Information System (INIS)

    Luo, Albert C.J.; Min Fuhong

    2011-01-01

    Highlights: → Synchronization dynamics of two distinct dynamical systems. → Synchronization, de-synchronization and instantaneous synchronization. → A controlled pendulum synchronizing with the Duffing oscillator. → Synchronization invariant set. → Synchronization parameter map. - Abstract: In this paper, synchronization dynamics of two different dynamical systems is investigated through the theory of discontinuous dynamical systems. The necessary and sufficient conditions for the synchronization, de-synchronization and instantaneous synchronization (penetration or grazing) are presented. Using such a synchronization theory, the synchronization of a controlled pendulum with the Duffing oscillator is systematically discussed as a sampled problem, and the corresponding analytical conditions for the synchronization are presented. The synchronization parameter study is carried out for a better understanding of synchronization characteristics of the controlled pendulum and the Duffing oscillator. Finally, the partial and full synchronizations of the controlled pendulum with periodic and chaotic motions are presented to illustrate the analytical conditions. The synchronization of the Duffing oscillator and pendulum are investigated in order to show the usefulness and efficiency of the methodology in this paper. The synchronization invariant domain is obtained. The technique presented in this paper should have a wide spectrum of applications in engineering. For example, this technique can be applied to the maneuvering target tracking, and the others.

  19. Paternal kin recognition in the high frequency / ultrasonic range in a solitary foraging mammal

    Directory of Open Access Journals (Sweden)

    Kessler Sharon E

    2012-11-01

    Full Text Available Abstract Background Kin selection is a driving force in the evolution of mammalian social complexity. Recognition of paternal kin using vocalizations occurs in taxa with cohesive, complex social groups. This is the first investigation of paternal kin recognition via vocalizations in a small-brained, solitary foraging mammal, the grey mouse lemur (Microcebus murinus, a frequent model for ancestral primates. We analyzed the high frequency/ultrasonic male advertisement (courtship call and alarm call. Results Multi-parametric analyses of the calls’ acoustic parameters and discriminant function analyses showed that advertisement calls, but not alarm calls, contain patrilineal signatures. Playback experiments controlling for familiarity showed that females paid more attention to advertisement calls from unrelated males than from their fathers. Reactions to alarm calls from unrelated males and fathers did not differ. Conclusions 1 Findings provide the first evidence of paternal kin recognition via vocalizations in a small-brained, solitarily foraging mammal. 2 High predation, small body size, and dispersed social systems may select for acoustic paternal kin recognition in the high frequency/ultrasonic ranges, thus limiting risks of inbreeding and eavesdropping by predators or conspecific competitors. 3 Paternal kin recognition via vocalizations in mammals is not dependent upon a large brain and high social complexity, but may already have been an integral part of the dispersed social networks from which more complex, kin-based sociality emerged.

  20. Synchronous, bilateral tonsillar carcinomas

    DEFF Research Database (Denmark)

    Saber, Camelia Nami; Grønhøj, Christian; Jensen, David Hebbelstrup

    2017-01-01

    -based, consecutive cohort of OPSCCs. METHODS: We identified all patients diagnosed with tonsillar squamous cell carcinoma (TSCC) in eastern Denmark during a 15-year period to detect the incidence of synchronous BiTSCCs. The tumours were assessed for p16Ink4a expression, the presence of HPV DNA and HPV genotypes....... Furthermore, we systematically reviewed the literature examining BiTSCCs. RESULTS: Of the total of 1119 TSCCs diagnosed in eastern Denmark from 2000 to 2014, we identified 12 BiTSCCs, nine of which initially presented as a cancer of unknown primary (CUP) in the neck. Nine cases were bilaterally HPV16 positive...... (HPV16+), while two cases were HPV16+ in one tonsil and respectively, HPV33 and HPV35 positive in the contralateral tonsil. One case was bilaterally HPV-negative. We also identified an increase in the incidence of BiTSCCs after 2012 when histological examination of the entire tonsil tissue became...

  1. Adrenalectomy does not improve survival rates of patients with solitary adrenal metastasis from non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Huang S

    2017-03-01

    73.2%. All of the patients had died by 30 months. There was no significant survival difference between patients who underwent primary and metastasis resection (n=10 and those treated conservatively (n=12, (P=0.209. Univariate analysis identified Eastern Cooperative Oncology Group performance status (ECOG PS as the significant predictor of survival (P=0.024. Age (<65 vs ≥65 years, sex, pathologic type, mediastinal lymph node stage (N2 vs N0/N1, primary tumor size (<5 vs ≥5 cm, primary location (central vs peripheral, metastatic tumor size (<5 vs ≥5 cm, metastasis laterality, synchronous metastasis, and metastatic field radiotherapy were not identified as potential prognostic factors in relation to survival rate. In multivariate analysis, a stepwise selection procedure allowed both ECOG PS (P=0.007, relative risk =3.57 and pathologic type (P=0.069 to enter the Cox’s hazard function.Conclusion: Primary and metastatic radical resection may not prolong the survival of NSCLC patients with solitary adrenal metastasis. ECOG PS and pathologic type might be the prognostic factors for these patients. Keywords: adrenalectomy, solitary metastasis, non-small cell lung cancer, survival, prognostic factors

  2. Diagnosis, treatment, and response assessment in solitary plasmacytoma

    DEFF Research Database (Denmark)

    Caers, J; Paiva, B; Zamagni, E

    2018-01-01

    Solitary plasmacytoma is an infrequent form of plasma cell dyscrasia that presents as a single mass of monoclonal plasma cells, located either extramedullary or intraosseous. In some patients, a bone marrow aspiration can detect a low monoclonal plasma cell infiltration which indicates a high ris......, but studies exploring the potential benefit of systemic therapies for high-risk patients are urgently needed. In this review, a panel of expert European hematologists updates the recommendations on the diagnosis and management of patients with solitary plasmacytoma....... of early progression to an overt myeloma disease. Before treatment initiation, whole body positron emission tomography-computed tomography or magnetic resonance imaging should be performed to exclude the presence of additional malignant lesions. For decades, treatment has been based on high-dose radiation...

  3. Existence and Stability of Relativistic Solitary Waves in Warm Plasmas

    International Nuclear Information System (INIS)

    Maza-Palacios, Marco A.; Herrera-Velazquez, J. Julio E.

    2006-01-01

    A variational mehod for one dimensional relativistic solitons is established, within the two fluid model framework, including finite temperature effects. Our starting point is a Lagrangian for a two species fluid plasma, which allows the deduction of the conserved quantities of the system by means of Noether's theorem, as well as the model equations. At a first stage, travelling wave solutions are studied with the usual shape of envelope solitary waves. It is found that bounded travelling waves (bright solitons) exist for most velocities, if both ions and electrons are assumed to be relativistic, except for a window at small values of v/c. In order to study their stability, we obtain the evolution equations of the solitary wave parameters, along those of radiation

  4. Solitary eccrine syringofibroadenoma with prominent plasma cell infiltration.

    Science.gov (United States)

    Kim, Ji Yeon; Kim, You Chan; Lee, Eun-So

    2007-02-01

    Eccrine syringofibroadenoma (ESFA) is a rare, benign, adnexal neoplasm thought to be eccrine ductal differentiation displaying variable clinical findings and characteristic histological features. It usually occurs as a solitary nodule on the extremities of an elderly person. Histological findings typically show a proliferation of anastomosing strands, cords, and columns of monomorphous epithelial cells that harbor eccrine duct formations embedded in a fibrovascular stroma. Acrosyringial nevus, though usually regarded as an identical lesion, is sometimes regarded as a different entity showing prominent plasma cell infiltration. We report two cases of solitary ESFA with prominent plasma cell infiltration. Clinicopathological features of both cases suggest that acrosyringeal nevus and ESFA may be of the same disease entity. Prominent plasma cell infiltration may be just one of the common histological features of ESFA.

  5. Nutritional recommendations for synchronized swimming.

    Science.gov (United States)

    Robertson, Sherry; Benardot, Dan; Mountjoy, Margo

    2014-08-01

    The sport of synchronized swimming is unique, because it combines speed, power, and endurance with precise synchronized movements and high-risk acrobatic maneuvers. Athletes must train and compete while spending a great amount of time underwater, upside down, and without the luxury of easily available oxygen. This review assesses the scientific evidence with respect to the physiological demands, energy expenditure, and body composition in these athletes. The role of appropriate energy requirements and guidelines for carbohydrate, protein, fat, and micronutrients for elite synchronized swimmers are reviewed. Because of the aesthetic nature of the sport, which prioritizes leanness, the risks of energy and macronutrient deficiencies are of significant concern. Relative Energy Deficiency in Sport and disordered eating/eating disorders are also of concern for these female athletes. An approach to the healthy management of body composition in synchronized swimming is outlined. Synchronized swimmers should be encouraged to consume a well-balanced diet with sufficient energy to meet demands and to time the intake of carbohydrate, protein, and fat to optimize performance and body composition. Micronutrients of concern for this female athlete population include iron, calcium, and vitamin D. This article reviews the physiological demands of synchronized swimming and makes nutritional recommendations for recovery, training, and competition to help optimize athletic performance and to reduce risks for weight-related medical issues that are of particular concern for elite synchronized swimmers.

  6. Generalized synchronization between chimera states

    Science.gov (United States)

    Andrzejak, Ralph G.; Ruzzene, Giulia; Malvestio, Irene

    2017-05-01

    Networks of coupled oscillators in chimera states are characterized by an intriguing interplay of synchronous and asynchronous motion. While chimera states were initially discovered in mathematical model systems, there is growing experimental and conceptual evidence that they manifest themselves also in natural and man-made networks. In real-world systems, however, synchronization and desynchronization are not only important within individual networks but also across different interacting networks. It is therefore essential to investigate if chimera states can be synchronized across networks. To address this open problem, we use the classical setting of ring networks of non-locally coupled identical phase oscillators. We apply diffusive drive-response couplings between pairs of such networks that individually show chimera states when there is no coupling between them. The drive and response networks are either identical or they differ by a variable mismatch in their phase lag parameters. In both cases, already for weak couplings, the coherent domain of the response network aligns its position to the one of the driver networks. For identical networks, a sufficiently strong coupling leads to identical synchronization between the drive and response. For non-identical networks, we use the auxiliary system approach to demonstrate that generalized synchronization is established instead. In this case, the response network continues to show a chimera dynamics which however remains distinct from the one of the driver. Hence, segregated synchronized and desynchronized domains in individual networks congregate in generalized synchronization across networks.

  7. Exact and explicit solitary wave solutions to some nonlinear equations

    International Nuclear Information System (INIS)

    Jiefang Zhang

    1996-01-01

    Exact and explicit solitary wave solutions are obtained for some physically interesting nonlinear evolutions and wave equations in physics and other fields by using a special transformation. These equations include the KdV-Burgers equation, the MKdV-Burgers equation, the combined KdV-MKdV equation, the Newell-Whitehead equation, the dissipative Φ 4 -model equation, the generalized Fisher equation, and the elastic-medium wave equation

  8. Existence of solitary waves in dipolar quantum gases

    KAUST Repository

    Antonelli, Paolo

    2011-02-01

    We study a nonlinear Schrdinger equation arising in the mean field description of dipolar quantum gases. Under the assumption of sufficiently strong dipolar interactions, the existence of standing waves, and hence solitons, is proved together with some of their properties. This gives a rigorous argument for the possible existence of solitary waves in BoseEinstein condensates, which originate solely due to the dipolar interaction between the particles. © 2010 Elsevier B.V. All rights reserved.

  9. Synchronization of weighted networks and complex synchronized regions

    International Nuclear Information System (INIS)

    Duan Zhisheng; Chen Guanrong; Huang Lin

    2008-01-01

    Since the Laplacian matrices of weighted networks usually have complex eigenvalues, the problem of complex synchronized regions should be investigated carefully. The present Letter addresses this important problem by converting it to a matrix stability problem with respect to a complex parameter, which gives rise to several types of complex synchronized regions, including bounded, unbounded, disconnected, and empty regions. Because of the existence of disconnected synchronized regions, the convexity characteristic of stability for matrix pencils is further discussed. Then, some efficient methods for designing local feedback controllers and inner-linking matrices to enlarge the synchronized regions are developed and analyzed. Finally, a weighted network of smooth Chua's circuits is presented as an example for illustration

  10. Solitary central osteoma of the jaws: a diagnostic dilemma.

    Science.gov (United States)

    Kaplan, Ilana; Nicolaou, Zoe; Hatuel, Dorian; Calderon, Shlomo

    2008-09-01

    Osteomas are relatively rare benign osteogenic neoplasms, characterized by the proliferation of compact and/or cancellous bone. Osteomas can develop as peripheral (periosteal) masses attached to the cortical plates or as central lesions arising from endosteal bone surfaces. Although multiple osteomas of the jaws are a hallmark of Gardner syndrome (familial adenomatous polyposis), nonsyndromic cases are typically solitary. A search of the literature identified 91 well documented cases of solitary osteoma of the jaws published since 1955: 93.4% were peripheral and only 6.6% central, a ratio of 14:1 in favor of peripheral osteomas. Solitary central osteomas of the jaws seem to be very rare, with only 6 such cases reported since 1955. Adding the 4 new cases described here brings the total to 10 central osteomas, 30% occurring in the maxilla and 70% in the mandible. Whereas peripheral osteomas are fairly easy to diagnose, central osteomas pose a more challenging diagnostic problem and need to be differentiated from other similar lesions of the jaws, such as central ossifying fibroma, condensing osteitis, idiopathic osteosclerosis, osteoblastoma, cementoblastoma, and complex odontoma. With such a low number of cases of central osteoma reported, the objectives of the present report are to describe 4 new cases, analyze the clinical and radiographic characteristics, and discuss the features which distinguish these lesions from other similar lesions of the jaws.

  11. Laparoscopic warm renal ischemia in the solitary porcine kidney model.

    Science.gov (United States)

    Baldwin, D Duane; Maynes, Lincoln J; Berger, Kenneth A; Desai, Premal J; Zuppan, Craig W; Zimmerman, Grenith J; Winkielman, Ada M; Sterling, Todd H; Tsai, Christopher K; Ruckle, Herbert C

    2004-09-01

    To determine the effect of a laparoscopic approach on warm renal ischemia in the pig with a solitary kidney. Although the maximal safe duration for warm ischemia during open partial nephrectomy is commonly accepted to be 30 minutes, the maximal safe ischemic time during laparoscopic partial nephrectomy has not been previously determined. Sixteen farm pigs underwent unilateral laparoscopic right nephrectomy. Two weeks later, the pigs underwent complete laparoscopic mobilization of the remaining left kidney and were randomized to complete hilar clamp times of 0, 30, 60, or 90 minutes. Serum creatinine was evaluated before right nephrectomy and at days 0, 2, 4, 7, 14, and 30 after renal ischemia during laparoscopy. All renal specimens were evaluated by an experienced nephropathologist in a blinded fashion. The serum creatinine remained stable at all points in the control and 30-minute ischemia groups. The serum creatinine level rose initially on days 2 and 4 in the 60-minute and 90-minute ischemia groups but returned to baseline by day 7. At harvest, no statistically significant difference was found among the groups in serum creatinine or histologic features. Renal ischemic times up to 90 minutes during laparoscopy were well tolerated by the solitary porcine kidney. Possible explanations for this finding include the protective effect of a solitary kidney and the potential protective effect of relative ischemic preconditioning provided by the pneumoperitoneum.

  12. Distress tolerance in social versus solitary college student drinkers.

    Science.gov (United States)

    Williams, Catherine L; Vik, Peter W; Wong, Maria M

    2015-11-01

    Low distress tolerance has been an inconsistent predictor of alcohol-related consequences in college students, but its relationships to depression and coping motives for alcohol have received stronger support. Research on college students who drink heavily in isolation suggests that this population is more likely to have a greater number and severity of alcohol-related problems, depression, and coping motives. Solitary heavy drinkers were therefore hypothesized to have lower distress tolerance than other drinkers. This study examined differences in self-reported and behavioral distress tolerance across two groups of university students: those who endorsed heavy solitary drinking (20.1%) versus those who endorsed other types of drinking. Students completed a self-report measure (Distress Intolerance Self-Report, or DISR) and behavioral measure of distress tolerance (Paced Auditory Serial Addition Test, or PASAT). Students who reported drinking heavily in isolation differed from other students on the DISR, F(1, 132) = 4.645, p = .033, η(2) = .034, but not on the PASAT, F(1, 132) = 0.056, p = .813. These students also endorsed more coping motives for alcohol. Distress tolerance did not predict drinking consequences directly, yet a mediation model linking distress tolerance to consequences through coping motives supports previous findings of distress tolerance as a distal, indirect predictor of drinking problems. The unique characteristics of solitary binge drinkers and the significance of distress tolerance as an indirect predictor of alcohol-related consequences are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Propagation of three-dimensional electron-acoustic solitary waves

    Science.gov (United States)

    Shalaby, M.; El-Labany, S. K.; Sabry, R.; El-Sherif, L. S.

    2011-06-01

    Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.

  14. Propagation of three-dimensional electron-acoustic solitary waves

    International Nuclear Information System (INIS)

    Shalaby, M.; El-Sherif, L. S.; El-Labany, S. K.; Sabry, R.

    2011-01-01

    Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.

  15. Peptide and lipid modulation of glutamatergic afferent synaptic transmission in the solitary tract nucleus

    Directory of Open Access Journals (Sweden)

    Michael C. Andresen

    2013-01-01

    Full Text Available The brainstem nucleus of the solitary tract (NTS holds the first central neurons in major homeostatic reflex pathways. These homeostatic reflexes regulate and coordinate multiple organ systems from gastrointestinal to cardiopulmonary functions. The core of many of these pathways arise from cranial visceral afferent neurons that enter the brain as the solitary tract (ST with more than two-thirds arising from the gastrointestinal system. About one quarter of ST afferents have myelinated axons but the majority are classed as unmyelinated C-fibers. All ST afferents release the fast neurotransmitter glutamate with remarkably similar, high-probability release characteristics. Second order NTS neurons receive surprisingly limited primary afferent information with one or two individual inputs converging on single second order NTS neurons. A- and C-fiber afferents never mix at NTS second order neurons. Many transmitters modify the basic glutamatergic excitatory postsynaptic current (EPSC often by reducing glutamate release or interrupting terminal depolarization. Thus, a distinguishing feature of ST transmission is presynaptic expression of G-protein coupled receptors for peptides common to peripheral or forebrain (e.g. hypothalamus neuron sources. Presynaptic receptors for angiotensin (AT1, vasopressin (V1a, oxytocin (OT, opioid (MOR, ghrelin (GHSR1 and cholecystokinin (CCK differentially control glutamate release on particular subsets of neurons with most other ST afferents unaffected. Lastly, lipid-like signals are transduced by two key ST presynaptic receptors, the transient receptor potential vanilloid type 1 (TRPV1 and the cannabinoid receptor (CB1 that oppositely control glutamate release. Increasing evidence suggests that peripheral nervous signaling mechanisms are repurposed at central terminals to control excitation and are major sites of signal integration of peripheral and central inputs particularly from the hypothalamus.

  16. Incidence of metachronous gastric cancer in the remnant stomach after synchronous multiple cancer surgery.

    Science.gov (United States)

    Nozaki, Isao; Hato, Shinji; Kobatake, Takaya; Ohta, Koji; Kubo, Yoshirou; Nishimura, Rieko; Kurita, Akira

    2014-01-01

    In the preoperative evaluation for gastric cancer, high-resolution endoscopic technologies allow us to detect small accessory lesions. However, it is not known if the gastric remnant after partial gastrectomy for synchronous multiple gastric cancers has a greater risk for metachronous cancer. The purpose of this study was to determine the incidence of metachronous cancer in this patient subset compared with that after solitary cancer surgery. Data on a consecutive series of 1,281 patients gastrectomized for early gastric cancer from 1991 to 2007 were analyzed retrospectively. The 715 gastric remnants after distal gastrectomy were periodically surveyed by endoscopic examination in Shikoku Cancer Center. Among those surveyed cases, 642 patients were pathologically diagnosed with solitary lesion (SO group) and 73 patients with synchronous multiple lesions (MU group) at the time of the initial surgery. In the follow-up period, 15 patients in the SO group and 3 patients in the MU group were diagnosed as having metachronous cancer in the gastric remnant. The cumulative 4-year incidence rate was 1.9 % in the SO group and 5.5 % in the MU group. The difference did not reach the significant level by the log-rank test. The incidence of metachronous cancer is higher after multiple cancer surgery; however, the difference is not statistically significant.

  17. Noncoherent Symbol Synchronization Techniques

    Science.gov (United States)

    Simon, Marvin

    2005-01-01

    Traditional methods for establishing symbol synchronization (sync) in digital communication receivers assume that carrier sync has already been established, i.e., the problem is addressed at the baseband level assuming that a 'perfect' estimate of carrier phase is available. We refer to this approach as coherent symbol sync. Since, for NRZ signaling, a suppressed carrier sync loop such as an I-Q Costas loop includes integrate-and-dump (I and D) filters in its in-phase (1) and quadrature (Q) arms, the traditional approach is to first track the carrier in the absence of symbol sync information, then feed back the symbol sync estimate to these filters, and then iterate between the two to a desirable operating level In this paper, we revisit the symbol sync problem by examining methods for obtaining such sync in the absence of carrier phase information, i.e., so-called noncoherent symbol sync loops. We compare the performance of these loops with that of a well-known coherent symbol sync loop and examine the conditions under which one is preferable over the other.

  18. Potential mechanisms for imperfect synchronization in parkinsonian basal ganglia.

    Directory of Open Access Journals (Sweden)

    Choongseok Park

    Full Text Available Neural activity in the brain of parkinsonian patients is characterized by the intermittently synchronized oscillatory dynamics. This imperfect synchronization, observed in the beta frequency band, is believed to be related to the hypokinetic motor symptoms of the disorder. Our study explores potential mechanisms behind this intermittent synchrony. We study the response of a bursting pallidal neuron to different patterns of synaptic input from subthalamic nucleus (STN neuron. We show how external globus pallidus (GPe neuron is sensitive to the phase of the input from the STN cell and can exhibit intermittent phase-locking with the input in the beta band. The temporal properties of this intermittent phase-locking show similarities to the intermittent synchronization observed in experiments. We also study the synchronization of GPe cells to synaptic input from the STN cell with dependence on the dopamine-modulated parameters. Earlier studies showed how the strengthening of dopamine-modulated coupling may lead to transitions from non-synchronized to partially synchronized dynamics, typical in Parkinson's disease. However, dopamine also affects the cellular properties of neurons. We show how the changes in firing patterns of STN neuron due to the lack of dopamine may lead to transition from a lower to a higher coherent state, roughly matching the synchrony levels observed in basal ganglia in normal and parkinsonian states. The intermittent nature of the neural beta band synchrony in Parkinson's disease is achieved in the model due to the interplay of the timing of STN input to pallidum and pallidal neuronal dynamics, resulting in sensitivity of pallidal output to the phase of the arriving STN input. Thus the mechanism considered here (the change in firing pattern of subthalamic neurons through the dopamine-induced change of membrane properties may be one of the potential mechanisms responsible for the generation of the intermittent synchronization

  19. Existence domain of the compressive ion acoustic super solitary wave in a two electron temperature warm multi-ion plasma

    Science.gov (United States)

    Steffy, S. V.; Ghosh, S. S.

    2017-10-01

    The transition of an ion acoustic solitary wave into a "supersoliton," or a super solitary wave have been explored in a two electron temperature warm multi-ion plasma using the Sagdeev pseudopotential technique. It is generally believed that the ion acoustic solitary wave can be transformed to a super solitary wave only through a double layer. The present work shows that the transition route of an ion acoustic solitary wave to a super solitary wave is not unique. Depending on the electron temperature ratio, a regular solitary wave may transform to a super solitary wave either via the double layer, or through an extra-nonlinear solitary structure whose morphology differs from that of a regular one. These extra-nonlinear structures are associated with a fluctuation of the charge separation within the potential profile and are named as "variable solitary waves." Depending on these analyses, the upper and lower bounds of a super solitary wave have been deciphered and its existence domain has been delineated in the parametric space. It reveals that super solitary waves are a subset of a more generalized class of extra-nonlinear solitary structures called variable solitary waves.

  20. Cross-spectrum symbol synchronization

    Science.gov (United States)

    Mccallister, R. D.; Simon, M. K.

    1981-01-01

    A popular method of symbol synchronization exploits one aspect of generalized harmonic analysis, normally referred to as the cross-spectrum. Utilizing nonlinear techniques, the input symbol energy is effectively concentrated onto multiples of the symbol clock frequency, facilitating application of conventional phase lock synchronization techniques. A general treatment of the cross-spectrum technique is developed and shown to be applicable across a broad class of symbol modulation formats. An important specific symbol synchronization application is then treated, focusing the general development to provide both insight and quantitative measure of the performance impact associated with variation in these key synchronization parameters: symbol modulation format, symbol transition probability, symbol energy to noise density ratio, and symbol rate to filter bandwidth ratio.

  1. Incoherence-Mediated Remote Synchronization

    Science.gov (United States)

    Zhang, Liyue; Motter, Adilson E.; Nishikawa, Takashi

    2017-04-01

    In previously identified forms of remote synchronization between two nodes, the intermediate portion of the network connecting the two nodes is not synchronized with them but generally exhibits some coherent dynamics. Here we report on a network phenomenon we call incoherence-mediated remote synchronization (IMRS), in which two noncontiguous parts of the network are identically synchronized while the dynamics of the intermediate part is statistically and information-theoretically incoherent. We identify mirror symmetry in the network structure as a mechanism allowing for such behavior, and show that IMRS is robust against dynamical noise as well as against parameter changes. IMRS may underlie neuronal information processing and potentially lead to network solutions for encryption key distribution and secure communication.

  2. Neural synchronization during face-to-face communication.

    Science.gov (United States)

    Jiang, Jing; Dai, Bohan; Peng, Danling; Zhu, Chaozhe; Liu, Li; Lu, Chunming

    2012-11-07

    Although the human brain may have evolutionarily adapted to face-to-face communication, other modes of communication, e.g., telephone and e-mail, increasingly dominate our modern daily life. This study examined the neural difference between face-to-face communication and other types of communication by simultaneously measuring two brains using a hyperscanning approach. The results showed a significant increase in the neural synchronization in the left inferior frontal cortex during a face-to-face dialog between partners but none during a back-to-back dialog, a face-to-face monologue, or a back-to-back monologue. Moreover, the neural synchronization between partners during the face-to-face dialog resulted primarily from the direct interactions between the partners, including multimodal sensory information integration and turn-taking behavior. The communicating behavior during the face-to-face dialog could be predicted accurately based on the neural synchronization level. These results suggest that face-to-face communication, particularly dialog, has special neural features that other types of communication do not have and that the neural synchronization between partners may underlie successful face-to-face communication.

  3. Differences between endocrinologists and endocrine surgeons in management of the solitary thyroid nodule

    DEFF Research Database (Denmark)

    Walsh, John P; Ryan, Simon A; Lisewski, Dean

    2007-01-01

    BACKGROUND: It is not known whether management of the solitary thyroid nodule differs between endocrinologists and endocrine surgeons. METHODS: A questionnaire containing a hypothetical case (a 42-year-old euthyroid woman with a 2-x-3-cm solitary thyroid nodule) and 13 clinical variations was sent...... Thyroid Association members (predominantly endocrinologists) demonstrated considerable international differences in management. CONCLUSION: There are clinically significant differences between Australian endocrinologists and endocrine surgeons in management of the solitary thyroid nodule...

  4. Optimization models for synchronization planning

    OpenAIRE

    Morey, Christopher

    1991-01-01

    Approved for public release; distribution is unlimited Planning for the synchronization of activities on the battlefield for an Army battalion task force requires detailed planning for movement of subordinate units, allocation of personnel and assets to tasks, and many other activities to ensure that maximum damage is inflicted on an enemy force. Currently, this synchronization planning is done manually by task force officers, primarily the operations officer. The process is time consumi...

  5. Leader emergence through interpersonal neural synchronization.

    Science.gov (United States)

    Jiang, Jing; Chen, Chuansheng; Dai, Bohan; Shi, Guang; Ding, Guosheng; Liu, Li; Lu, Chunming

    2015-04-07

    The neural mechanism of leader emergence is not well understood. This study investigated (i) whether interpersonal neural synchronization (INS) plays an important role in leader emergence, and (ii) whether INS and leader emergence are associated with the frequency or the quality of communications. Eleven three-member groups were asked to perform a leaderless group discussion (LGD) task, and their brain activities were recorded via functional near infrared spectroscopy (fNIRS)-based hyperscanning. Video recordings of the discussions were coded for leadership and communication. Results showed that the INS for the leader-follower (LF) pairs was higher than that for the follower-follower (FF) pairs in the left temporo-parietal junction (TPJ), an area important for social mentalizing. Although communication frequency was higher for the LF pairs than for the FF pairs, the frequency of leader-initiated and follower-initiated communication did not differ significantly. Moreover, INS for the LF pairs was significantly higher during leader-initiated communication than during follower-initiated communications. In addition, INS for the LF pairs during leader-initiated communication was significantly correlated with the leaders' communication skills and competence, but not their communication frequency. Finally, leadership could be successfully predicted based on INS as well as communication frequency early during the LGD (before half a minute into the task). In sum, this study found that leader emergence was characterized by high-level neural synchronization between the leader and followers and that the quality, rather than the frequency, of communications was associated with synchronization. These results suggest that leaders emerge because they are able to say the right things at the right time.

  6. Synchronous thymoma and oligodendroglioma: A rare association.

    Science.gov (United States)

    Vaziri, Mohammad; Rad, Kamelia

    2016-01-01

    Patients with thymoma are found to have another systemic illness and a broadly increased risk for secondary malignancies. We present the case of a 53-year-old female patient who harbored two synchronous primary malignant neoplasms-an anaplastic oligodendroglioma of the right frontal lobe and an anterior mediastinal thymoma. A 53-year-old female patient presented in her first hospital admission with nausea, chest pain and non-pulsatile bitemporal headache. Continued headache and nausea along with negative cardiac findings prompted radiological evaluation including chest CT scan and brain CT scan which revealed simultaneous anterior mediastinal mass and frontal lobe calcification respectively. The patient underwent craniotomy and the pathological diagnosis was anaplastic oligodendriglioma. The anterior mediastinal tumor resection was performed three months later, while the patient had no newly onset of any symptoms necessitating more investigation. Multiple primary malignancies have been diagnosed by the following criteria: each tumor must have an obvious picture of malignancy, each must be separate and discrete and the probability that one was a metastatic lesion from the other must be excluded. Treatment strategies in cases of double malignancy involve treating the malignancy that is more advanced first. In our case we concluded that synchronous double malignancy can be treated successfully according to the above mentioned criteria. Clinicians should be aware of the possibility of synchronous malignancies in order to use screening procedures in patients with reported increased risk of double malignancy. Such clinical alertness may lead to a better outcome for double primary tumor cases. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Hybrid synchronization of hyperchaotic Lu system

    Indian Academy of Sciences (India)

    In this paper, we study the hybrid synchronization between two identical hyperchaotic Lu systems. Hybrid synchronization of hyperchaotic Lu system is achieved through synchronization of two pairs of states and anti-synchronization of the other two pairs of states. Active controls are designed to achieve hybrid ...

  8. Hybrid synchronization of hyperchaotic Lu system

    Indian Academy of Sciences (India)

    hyperchaotic Lu systems. Hybrid synchronization of hyperchaotic Lu system is achieved through synchronization of two pairs of states and anti-synchronization of the other two pairs of states. Active controls are designed to achieve hybrid synchronization between drive and response systems using the sum and difference of ...

  9. Multiswitching combination–combination synchronization of chaotic ...

    Indian Academy of Sciences (India)

    2017-02-09

    Feb 9, 2017 ... Abstract. In this paper, a novel synchronization scheme is investigated for a class of chaotic systems. The multiswitching synchronization scheme is extended to the combination–combination synchronization scheme such that the combination of state variables of two drive systems synchronize with different ...

  10. Multiswitching combination–combination synchronization of chaotic ...

    Indian Academy of Sciences (India)

    In this paper, a novel synchronization scheme is investigated for a class of chaotic systems. Themultiswitching synchronization scheme is extended to the combination–combination synchronization scheme such that the combination of state variables of two drive systems synchronize with different combination of state ...

  11. A new model for algebraic Rossby solitary waves in rotation fluid and its solution

    Science.gov (United States)

    Chen, Yao-Deng; Yang, Hong-Wei; Gao, Yu-Fang; Yin, Bao-Shu; Feng, Xing-Ru

    2015-09-01

    A generalized Boussinesq equation that includes the dissipation effect is derived to describe a kind of algebraic Rossby solitary waves in a rotating fluid by employing perturbation expansions and stretching transformations of time and space. Using this equation, the conservation laws of algebraic Rossby solitary waves are discussed. It is found that the mass, the momentum, the energy, and the velocity of center of gravity of the algebraic solitary waves are conserved in the propagation process. Finally, the analytical solution of the equation is generated. Based on the analytical solution, the properties of the algebraic solitary waves and the dissipation effect are discussed. The results point out that, similar to classic solitary waves, the dissipation can cause the amplitude and the speed of solitary waves to decrease; however, unlike classic solitary waves, the algebraic solitary waves can split during propagation and the decrease of the detuning parameter can accelerate the occurrence of the solitary waves fission phenomenon. Project supported by the Shandong Provincial Key Laboratory of Marine Ecology and Environment and Disaster Prevention and Mitigation Project, China (Grant No. 2012010), the National Natural Science Foundation of China (Grant Nos. 41205082 and 41476019), the Special Funds for Theoretical Physics of the National Natural Science Foundation of China (Grant No. 11447205), and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), China.

  12. Synchronization and anti-synchronization coexist in Chen-Lee chaotic systems

    International Nuclear Information System (INIS)

    Chen, J.-H.; Chen, H.-K.; Lin, Y.-K.

    2009-01-01

    This study demonstrates that synchronization and anti-synchronization can coexist in Chen-Lee chaotic systems by direct linear coupling. Based on Lyapunov's direct method, a linear controller was designed to assure that two different types of synchronization can simultaneously be achieved. Further, the hybrid projective synchronization of Chen-Lee chaotic systems was studied using a nonlinear control scheme. The nonlinear controller was designed according to the Lyapunov stability theory to guarantee the hybrid projective synchronization, including synchronization, anti-synchronization, and projective synchronization. Finally, numerical examples are presented in order to illustrate the proposed synchronization approach.

  13. Adaptive Time Synchronization for Homogeneous WSNs

    Directory of Open Access Journals (Sweden)

    Siddhartha Chauhan

    2012-11-01

    cluster heads (CHs are synchronized with the sink and then the cluster nodes (CNs are synchronized with their respective CHs. CNs are synchronized with the help of time synchronization node (TSN chosen by the respective CHs. Simulation results show that proposed protocol requires considerably fewer synchronization messages as compared with the reference broadcast synchronization (RBS protocol and minimum variance unbiased estimation (MUVE method. Clock skew correction mechanism applied in proposed protocol guarantees long term stability and hence decreases re‐synchronization frequency thereby conserving more energy.

  14. Synchronized drumming enhances activity in the caudate and facilitates prosocial commitment--if the rhythm comes easily

    NARCIS (Netherlands)

    Kokal, Idil; Engel, Annerose; Kirschner, Sebastian; Keysers, Christian

    2011-01-01

    Why does chanting, drumming or dancing together make people feel united? Here we investigate the neural mechanisms underlying interpersonal synchrony and its subsequent effects on prosocial behavior among synchronized individuals. We hypothesized that areas of the brain associated with the

  15. Experience drives synchronization

    DEFF Research Database (Denmark)

    Pallesen, Karen Johanne; Bailey, Christopher J; Brattico, Elvira

    2015-01-01

    Musical expertise is associated with structural and functional changes in the brain that underlie facilitated auditory perception. We investigated whether the phase locking (PL) and amplitude modulations (AM) of neuronal oscillations in response to musical chords are correlated with musical......, while watching a silenced movie. We then analyzed the PL and AM of ongoing oscillations in the theta (4–8 Hz) alpha (8–14 Hz), beta- (14–30 Hz) and gamma- (30–80 Hz) bands to these chords. We found that musical expertise was associated with strengthened PL of ongoing oscillations to chords over a wide...

  16. Unidirectional synchronization of Hodgkin-Huxley neurons

    International Nuclear Information System (INIS)

    Cornejo-Perez, Octavio; Femat, Ricardo

    2005-01-01

    Synchronization dynamics of two noiseless Hodgkin-Huxley (HH) neurons under the action of feedback control is studied. The spiking patterns of the action potentials evoked by periodic external modulations attain synchronization states under the feedback action. Numerical simulations for the synchronization dynamics of regular-irregular desynchronized spiking sequences are displayed. The results are discussed in context of generalized synchronization. It is also shown that the HH neurons can be synchronized in face of unmeasured states

  17. Unidirectional synchronization of Hodgkin-Huxley neurons

    Energy Technology Data Exchange (ETDEWEB)

    Cornejo-Perez, Octavio [Division de Matematicas Aplicadas y Sistemas, Computacionales, IPICYT, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosi (Mexico)]. E-mail: octavio@ipicyt.edu.mx; Femat, Ricardo [Division de Matematicas Aplicadas y Sistemas, Computacionales, IPICYT, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosi (Mexico)]. E-mail: rfemat@ipicyt.edu.mx

    2005-07-01

    Synchronization dynamics of two noiseless Hodgkin-Huxley (HH) neurons under the action of feedback control is studied. The spiking patterns of the action potentials evoked by periodic external modulations attain synchronization states under the feedback action. Numerical simulations for the synchronization dynamics of regular-irregular desynchronized spiking sequences are displayed. The results are discussed in context of generalized synchronization. It is also shown that the HH neurons can be synchronized in face of unmeasured states.

  18. Chaotic neuron dynamics, synchronization and feature binding

    Science.gov (United States)

    Arecchi, F. T.

    2004-07-01

    Neuroscience studies how a large collection of coupled neurons combines external data with internal memories into coherent patterns of meaning. Such a process is called “feature binding”, insofar as the coherent patterns combine together features which are extracted separately by specialized cells, but which do not make sense as isolated items. A powerful conjecture, with experimental confirmation, is that feature binding implies the mutual synchronization of axonal spike trains in neurons which can be far away and yet contribute to a well defined perception by sharing the same time code. Based on recent investigations of homoclinic chaotic systems, and how they mutually synchronize, a novel conjecture on the dynamics of the single neuron is formulated. Homoclinic chaos implies the recurrent return of the dynamical trajectory to a saddle focus, in whose neighbourhood the system susceptibility (response to an external perturbation) is very high and hence it is very easy to lock to an external stimulus. Thus homoclinic chaos appears as the easiest way to encode information by a train of equal spikes occurring at erratic times. In conventional measurements we read the number indicated by a meter's pointer and assign to the measured object a set position corresponding to that number. On the contrary, a time code requires a decision time T¯ sufficiently longer than the minimal interspike separation t1, so that the total number of different set elements is related in some way to the size T¯/t 1. In neuroscience it has been shown that T¯≃200 ms while t 1≃3 ms. In a sensory layer of the brain neocortex an external stimulus spreads over a large assembly of neurons building up a collective state, thus synchronization of trains of different individual neurons is the basis of a coherent perception. The percept space can be given a metric structure by introducing a distance measure. This distance is conjugate of the duration time in the sense that an uncertainty

  19. SOLITARY PARAGANGLIOMA OF THE HYPOGLOSSAL NERVE: CASE REPORT.

    LENUS (Irish Health Repository)

    2012-02-01

    SOLITARY PARAGANGLIOMA OF THE HYPOGLOSSAL NERVE:: Case Report BACKGROUND AND IMPORTANCE:: We report the case history of solitary hypoglossal paraganglioma in a 64-year-old woman. The surgical difficulties encountered in the removal of this challenging tumour are discussed with literature review. CLINICAL PRESENTATION:: A 64-year-old woman presented with a short history of dysphonia, occasional dysphagia, tinnitus, altered taste, and unilateral left sided tongue wasting. On examination there was left lower motor hypoglossal paralysis. Imaging showed a discrete enhancing lobulated mass, measuring 2cm x 2cm, in the region of the hypoglossal nerve extending into the hypoglossal canal suggestive of hypoglossal paraganglioma. A left dorsolateral sub occipital craniotomy was carried out in the sitting position. The hypoglossal nerve appeared to be enlarged and the jugular foramen was normal. Complete surgical debulking of the tumour was not attempted due to its vascular nature. The nerve was decompressed and neuropathology confirmed a low grade paraganglioma arising from the hypoglossal nerve. The patient is scheduled to receive stereotactic radiation for further management. CONCLUSION:: When a case of solitary hypoglossal paraganglioma is encountered in clinical practice, the aim of management should be mainly focussed on achieving a diagnosis and preserving the hypoglossal nerve function. If there is evidence of vascularity in the lesion noted in the MRI scan, a pre-operative angiogram should be performed with a view for embolisation.We decompressed the hypoglossal canal and achieved a good improvement in the patient\\'s symptoms. We recommend stereotactic radiosurgery for remnant and small hypoglossal tumours and regular follow up with MRI scans.

  20. SOLITARY PARAGANGLIOMA OF THE HYPOGLOSSAL NERVE: CASE REPORT.

    LENUS (Irish Health Repository)

    Raza, Kazim

    2011-01-25

    SOLITARY PARAGANGLIOMA OF THE HYPOGLOSSAL NERVE:: Case Report BACKGROUND AND IMPORTANCE:: We report the case history of solitary hypoglossal paraganglioma in a 64-year-old woman. The surgical difficulties encountered in the removal of this challenging tumour are discussed with literature review. CLINICAL PRESENTATION:: A 64-year-old woman presented with a short history of dysphonia, occasional dysphagia, tinnitus, altered taste, and unilateral left sided tongue wasting. On examination there was left lower motor hypoglossal paralysis. Imaging showed a discrete enhancing lobulated mass, measuring 2cm x 2cm, in the region of the hypoglossal nerve extending into the hypoglossal canal suggestive of hypoglossal paraganglioma. A left dorsolateral sub occipital craniotomy was carried out in the sitting position. The hypoglossal nerve appeared to be enlarged and the jugular foramen was normal. Complete surgical debulking of the tumour was not attempted due to its vascular nature. The nerve was decompressed and neuropathology confirmed a low grade paraganglioma arising from the hypoglossal nerve. The patient is scheduled to receive stereotactic radiation for further management. CONCLUSION:: When a case of solitary hypoglossal paraganglioma is encountered in clinical practice, the aim of management should be mainly focussed on achieving a diagnosis and preserving the hypoglossal nerve function. If there is evidence of vascularity in the lesion noted in the MRI scan, a pre-operative angiogram should be performed with a view for embolisation.We decompressed the hypoglossal canal and achieved a good improvement in the patient\\'s symptoms. We recommend stereotactic radiosurgery for remnant and small hypoglossal tumours and regular follow up with MRI scans.

  1. Solitary rectal ulcer syndrome: demographic, clinical, endoscopic and histological panorama

    International Nuclear Information System (INIS)

    Abbasi, A.; Bhutto, K. A.R.; Baloch, A.

    2015-01-01

    To assess the demographic, clinical, endoscopic and histological spectrum of Solitary Rectal Ulcer Syndrome (SRUS). Study Design: Cross-sectional observational study. Place and Duration of Study: Medical Unit-III, Civil Hospital Karachi (CHK) and Ward 7, Jinnah Postgraduate Medical Centre (JPMC), Karachi, from January 2009 to June 2012. Methodology: Patients with SRUS, based on characteristic endoscopic and histological findings, were enrolled. Patients were excluded if they had other causes of the rectal lesions (neoplasm, infection, inflammatory bowel disease, and trauma). Endoscopically, lesions were divided on the basis of number (solitary or multiple) and appearance (ulcerative, polypoidal/nodular or erythematous mucosa). Demographic, clinical and endoscopic characteristics of subjects were evaluated. Results: Forty-four patients met the inclusion criteria; 21 (47.7%) were females and 23 (52.3%) were males with overall mean age of 33.73 ±13.28 years. Symptom-wise 41 (93.2%) had bleeding per rectum, 39 (88.6%) had mucous discharge, 34 (77.3%) had straining, 34 (77.3%) had constipation, 32 (72.7%) had tenesmus, 5 (11.4%) had rectal prolapse and 2 (4.5%) had fecal incontinence. Twelve (27.27%) patients presented with hemoglobin less 10 gm/dl, 27 (61.36%) with 10 - 12 gm/dl and 05 (11.36%) subjects had hemoglobin more than 12 gm/dl. Endoscopically, 26 (59.1%) patients had mucosal ulceration, 11 (25.0%) had mucosal ulceration with polypoid characteristics; while only polypoid features were found in 7 (15.9%) subjects. Conclusion: Solitary rectal ulcer syndrome affects adults of both genders with diverse clinical presentation and nonspecific endoscopic features. (author)

  2. Solitary Rectal Ulcer Syndrome: Demographic, Clinical, Endoscopic and Histological Panorama.

    Science.gov (United States)

    Abbasi, Amanullah; Bhutto, Abdul Rabb; Taj, Ali; Aurangzaib; Baloch, Akhtar; Masroor, Muhammad; Munir, S M

    2015-12-01

    To assess the demographic, clinical, endoscopic and histological spectrum of Solitary Rectal Ulcer Syndrome (SRUS). Cross-sectional observational study. Medical Unit-III, Civil Hospital Karachi (CHK) and Ward 7, Jinnah Postgraduate Medical Centre (JPMC), Karachi, from January 2009 to June 2012. Patients with SRUS, based on characteristic endoscopic and histological findings, were enrolled. Patients were excluded if they had other causes of the rectal lesions (neoplasm, infection, inflammatory bowel disease, and trauma). Endoscopically, lesions were divided on the basis of number (solitary or multiple) and appearance (ulcerative, polypoidal/nodular or erythematous mucosa). Demographic, clinical and endoscopic characteristics of subjects were evaluated. Forty-four patients met the inclusion criteria; 21 (47.7%) were females and 23 (52.3%) were males with overall mean age of 33.73 ±13.28 years. Symptom-wise 41 (93.2%) had bleeding per rectum, 39 (88.6%) had mucous discharge, 34 (77.3%) had straining, 34 (77.3%) had constipation, 32 (72.7%) had tenesmus, 5 (11.4%) had rectal prolapse and 2 (4.5%) had fecal incontinence. Twelve (27.27%) patients presented with hemoglobin less 10 gm/dl, 27 (61.36%) with 10 - 12 gm/dl and 05 (11.36%) subjects had hemoglobin more than 12 gm/dl. Endoscopically, 26 (59.1%) patients had mucosal ulceration, 11 (25.0%) had mucosal ulceration with polypoid characteristics; while only polypoid features were found in 7 (15.9%) subjects. Solitary rectal ulcer syndrome affects adults of both genders with diverse clinical presentation and nonspecific endoscopic features.

  3. Solitary fibrous tumor arising in an intrathoracic goiter

    DEFF Research Database (Denmark)

    Larsen, Stine Rosenkilde; Godballe, Christian; Krogdahl, Annelise

    2010-01-01

    . CONCLUSION: The histological appearance and immunohistochemical reaction pattern of SFT is characteristic. The entity should be considered when dealing with a spindle cell lesion in the thyroid gland. All cases of this site of origin reported have had a benign clinical course. As only a small number of cases......BACKGROUND: Solitary fibrous tumor (SFT) is a rare spindle cell tumor most often found in the mediastinal pleura. Nineteen cases of SFT arising in the thyroid gland have been reported. We report a case of SFT of the thyroid gland with immunohistochemical and cytogenetic investigation. SUMMARY: A 58...

  4. A case of solitary fibrous tumor of the kidney

    Directory of Open Access Journals (Sweden)

    H N Naveen

    2011-01-01

    Full Text Available A solitary fibrous tumor (SFT is an unusual spindle cell neoplasm that usually occurs in the pleura but has recently been described in diverse extrapleural sites. Urogenital localization is rare and to our knowledge, only 39 cases of SFT of the kidney have been described. Although SFT of the kidney is extremely rare, this tumor must be included in the differential diagnosis, whenever a renal tumor consisting of mesenchymal elements is encountered. We report a case of a large SFT of the right kidney which was clinically and radiologically thought to be renal cell carcinoma and a final diagnosis of SFT was made only after immunohistochemical study.

  5. Slow solitary waves in multi-layered magnetic structures

    International Nuclear Information System (INIS)

    Ruderman, M.S.; Roberts, B.; Pelinovsky, E.N.; Petrukhin, N.S.

    2001-01-01

    The propagation of slow sausage surface waves in a multi-layered magnetic configuration is considered. The magnetic configuration consists of a central magnetic slab sandwiched between two identical magnetic slabs (with equilibrium quantities different from those in the central slab) which in turn are embedded between two identical semi-infinite regions. The dispersion equation is obtained in the linear approximation. The nonlinear governing equation describing waves with a characteristic wavelength along the central slab much larger than the slab thickness is derived. Solitary wave solutions to this equation are obtained in the case where these solutions deviate only slightly from the algebraic soliton of the Benjamin-Ono equation

  6. Laboratory Measurements of Electrostatic Solitary Structures Generated by Beam Injection

    International Nuclear Information System (INIS)

    Lefebvre, Bertrand; Chen, Li-Jen; Gekelman, Walter; Pribyl, Patrick; Vincena, Stephen; Kintner, Paul; Pickett, Jolene; Chiang, Franklin; Judy, Jack

    2010-01-01

    Electrostatic solitary structures are generated by injection of a suprathermal electron beam parallel to the magnetic field in a laboratory plasma. Electric microprobes with tips smaller than the Debye length (λ De ) enabled the measurement of positive potential pulses with half-widths 4 to 25λ De and velocities 1 to 3 times the background electron thermal speed. Nonlinear wave packets of similar velocities and scales are also observed, indicating that the two descend from the same mode which is consistent with the electrostatic whistler mode and result from an instability likely to be driven by field-aligned currents.

  7. Solitary fibrous tumor of the orbit presenting in pregnancy.

    Science.gov (United States)

    Das, Jayanta K; Sharma, Angshuman Sen; Deka, Akshay Ch; Das, Dipankar

    2009-01-01

    A 32-year-old woman, three months pregnant, reported with the complaint of protrusion of the right eye for six months. She gave history of rapid protrusion of eyeball for the last two months along with the history of double vision for the last one month. Computer tomography (CT) scan revealed a well-defined mass lesion in the intraconal space of the right orbit which was excised through a lateral orbitotomy approach. Histological examination and immunohistochemistry revealed a solitary fibrous tumor, which showed a rapid progression in pregnancy.

  8. Imaging of painful solitary lesions of the sacrum

    International Nuclear Information System (INIS)

    Peh, W. C. G.; Koh, W. L.; Kwek, J. W.; Htoo, M. M.; Tan, P. H.

    2007-01-01

    Full text: In patients with sacral pain, the painful symptoms may be caused by a variety of bony and soft tissue lesions. Benign lesions include giant cell tumour, neurogenic tumour, insufficiency fracture, infection and giant bone island. Malignant lesions include primary bone tumours, Ewing sarcoma, plasmacytoma, lymphoma and chordoma. Soft tissue tumours adjacent to or involving the sacrum may cause painful symptoms. A multimodality approach to imaging is required for full assessment of these lesions. This pictorial essay describes a range of common solitary sacral lesions that may cause pain, with emphasis on imaging features

  9. Linear Stability of the boundary layer under a solitary wave

    OpenAIRE

    Verschaeve, Joris C. G.; Pedersen, Geir K.

    2013-01-01

    A theoretical and numerical analysis of the linear stability of the boundary layer flow under a solitary wave is presented. In the present work, the nonlinear boundary layer equations are solved. The result is compared to the linear boundary layer solution in Liu et al. (2007) reveal- ing that both profiles are disagreeing more than has been found before. A change of frame of reference has been used to allow for a classical linear stability analysis without the need to redefine the notion of ...

  10. Metastatic melanoma mimicking solitary fibrous tumor: report of two cases.

    Science.gov (United States)

    Bekers, Elise M; van Engen-van Grunsven, Adriana C H; Groenen, Patricia J T A; Westdorp, Harm; Koornstra, Rutger H T; Bonenkamp, Johannes J; Flucke, Uta; Blokx, Willeke A M

    2014-02-01

    Malignant melanomas are known for their remarkable morphological variation and aberrant immunophenotype with loss of lineage-specific markers, especially in recurrences and metastases. Hot spot mutations in BRAF, NRAS, GNAQ, and GNA11 and mutations in KIT are oncogenic events in melanomas. Therefore, genotyping can be a useful ancillary diagnostic tool. We present one case each of recurrent and metastatic melanoma, both showing histological and immunohistochemical features of solitary fibrous tumor (SFT). Mutational analysis detected BRAF and NRAS mutations in the primary and secondary lesions, respectively. This result confirmed the diagnosis of recurrent/metastastic melanoma.

  11. Experiments and computation of onshore breaking solitary waves

    DEFF Research Database (Denmark)

    Jensen, A.; Mayer, Stefan; Pedersen, G.K.

    2005-01-01

    This is a combined experimental and computational study of solitary waves that break on-shore. Velocities and accelerations are measured by a two-camera PIV technique and compared to theoretical values from an Euler model with a VOF method for the free surface. In particular, the dynamics of a so......-called collapsing breaker is scrutinized and the closure between the breaker and the beach is found to be akin to slamming. To the knowledge of the authors, no velocity measurements for this kind of breaker have been previously reported....

  12. Explosive and solitary excitations in a very dense magnetoplasma

    Energy Technology Data Exchange (ETDEWEB)

    Sabry, R. [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)], E-mail: refaatsabry@mans.edu.eg; Moslem, W.M. [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)], E-mail: wmmoslem@hotmail.com; Shukla, P.K. [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)], E-mail: ps@tp4.rub.de

    2008-08-25

    A two-component dense magnetoplasma consisting of ions and degenerate electrons is considered. The basic set of hydrodynamic and Poisson equations are reduced to the Zakharov-Kuznetsov (ZK) equation by using the reductive perturbation technique. The basic features of the electrostatic excitations are investigated by applying a new direct method to the ZK equation. It is found that the latter has new solutions, which admit the propagation of either solitary or explosive pulses. The relevance of the new direct method to other nonlinear partial differential equations is also discussed.

  13. Burned-out seminoma revealed by solitary rib bone metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Nishisho, Toshihiko; Miyagi, Ryo; Sairyo, Koichi [Tokushima University Graduate School, Department of Orthopedics, Institute of Biomedical Sciences, Tokushima-city, Tokushima (Japan); Sakaki, Mika [Saitama Medical University International Medical Center, Department of Pathology, Hidaka-city, Saitama (Japan); Takao, Shoichiro [Tokushima University Graduate School, Department of Radiology, Institute of Biomedical Sciences, Tokushima-city, Tokushima (Japan)

    2017-10-15

    Burned-out tumor is a rare phenomenon in which a testicular tumor regresses in the primary lesion and progresses in a metastatic lesion. We report the case of a 30-year-old male with burned-out seminoma revealed by open biopsy of solitary 10th rib bone metastasis. He underwent inguinal orchiectomy, which revealed hyalinization, indicating a spontaneously regressed testicular tumor. Chemotherapy for seminoma was administered in three cycles of bleomycin + etoposide + cisplatin therapy. The chemotherapy was effective, and wide resection of the rib was subsequently performed. No postoperative chemotherapy was performed, and there has been no evidence of recurrence for 3 years postoperatively. (orig.)

  14. Splenectomy for solitary splenic metastasis of ovarian cancer

    International Nuclear Information System (INIS)

    Koh, Yang Seok; Kim, Jung Chul; Cho, Chol Kyoon

    2004-01-01

    Splenic metastases occur in rare cases with a few case reports of patients in the literature. Generally, splenic metastases mean late dissemination of a disease. Solitary splenic metastases from solid tumors are extremely unusual. We report a case of a patient with ovarian mucinous cystadenocarcinoma who underwent splenectomy for isolated parenchymal metastasis. Ovarian epithelial tumors comprised most of isolated splenic metastases from gynecologic tumor. When isolated splenic recurrence is suspected on image studies and serum tumor markers, intraabdominal gross findings should be examined to exclude peritoneal carcinomatosis. If only spleen was under suspicion of recurrence of ovarian cancer, splenectomy may play a therapeutic role

  15. Synchronization of two Hodgkin-Huxley neurons due to internal noise

    International Nuclear Information System (INIS)

    Casado, Jose Manuel

    2003-01-01

    It is well known that a strong coupling can synchronize a population of nonlinear oscillators. This fact has deep implications for the current understanding of information processing by the brain. The focus of this Letter is on the role of conductance noise on a system of two coupled Hodgkin-Huxley neurons in the so-called excitable region, where both neurons are at rest in the absence of noise. It is shown that, in this region, conductance noise allows the neurons to achieve both frequency and phase synchronization. This suggests that internal noise could play a role in the emergence of synchronous neural activity in populations of weakly coupled neurons

  16. Cognitive and physical training for the elderly: evaluating outcome efficacy by means of neurophysiological synchronization.

    Science.gov (United States)

    Frantzidis, Christos A; Ladas, Aristea-Kiriaki I; Vivas, Ana B; Tsolaki, Magda; Bamidis, Panagiotis D

    2014-07-01

    Recent neuroscientific research has demonstrated that both healthy and pathological aging induces alterations in the co-operative capacity of neuronal populations in the brain. Both compensatory and neurodegenerative mechanisms contribute to neurophysiological synchronization patterns, which provide a valuable marker for age-related cognitive decline. In this study, we propose that neuroplasticity-based training may facilitate coherent interaction of distant brain regions and consequently enhance cognitive performance in elderly people. If this is true, this would make neurophysiological synchronization a valid outcome measure to assess the efficacy of non-pharmacological interventions to prevent or delay age-related cognitive decline. The present study aims at providing an objective, synchronization-based tool to assess cognitive and/or physical interventions, adopting the notion of Relative Wavelet Entropy. This mathematical model employs a robust and parameter-free synchronization metric. By using data mining techniques, a distance value was computed for all participants so as to quantify the proximity of their individual profile to the mean group synchronization increase. In support of our hypothesis, results showed a significant increase in synchronization, for four electrode pairs, in the intervention group as compared to the active control group. It is concluded that the novel introduction of neurophysiological synchronization features could be used as a valid and reliable outcome measure; while the distance-based analysis could provide a reliable means of evaluating individual benefits. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Bodily Synchronization Underlying Joke Telling

    Directory of Open Access Journals (Sweden)

    R. C. Schmidt

    2014-08-01

    Full Text Available Advances in video and time series analysis have greatly enhanced our ability to study the bodily synchronization that occurs in natural interactions. Past research has demonstrated that the behavioral synchronization involved in social interactions is similar to dynamical synchronization found generically in nature. The present study investigated how the bodily synchronization in a joke telling task is spread across different nested temporal scales. Pairs of participants enacted knock-knock jokes and times series of their bodily activity were recorded. Coherence and relative phase analyses were used to evaluate the synchronization of bodily rhythms for the whole trial as well as at the subsidiary time scales of the whole joke, the setup of the punch line, the two-person exchange and the utterance. The analyses revealed greater than chance entrainment of the joke teller’s and joke responder’s movements at all time scales and that the relative phasing of the teller’s movements led those of the responder at the longer time scales. Moreover, this entrainment was greater when visual information about the partner’s movements was present but was decreased particularly at the shorter time scales when explicit gesturing in telling the joke was performed. In short, the results demonstrate that a complex interpersonal bodily dance occurs during structured conversation interactions and that this dance is constructed from a set of rhythms associated with the nested behavioral structure of the interaction.

  18. Vestibular hearing and neural synchronization.

    Science.gov (United States)

    Emami, Seyede Faranak; Daneshi, Ahmad

    2012-01-01

    Objectives. Vestibular hearing as an auditory sensitivity of the saccule in the human ear is revealed by cervical vestibular evoked myogenic potentials (cVEMPs). The range of the vestibular hearing lies in the low frequency. Also, the amplitude of an auditory brainstem response component depends on the amount of synchronized neural activity, and the auditory nerve fibers' responses have the best synchronization with the low frequency. Thus, the aim of this study was to investigate correlation between vestibular hearing using cVEMPs and neural synchronization via slow wave Auditory Brainstem Responses (sABR). Study Design. This case-control survey was consisted of twenty-two dizzy patients, compared to twenty healthy controls. Methods. Intervention comprised of Pure Tone Audiometry (PTA), Impedance acoustic metry (IA), Videonystagmography (VNG), fast wave ABR (fABR), sABR, and cVEMPs. Results. The affected ears of the dizzy patients had the abnormal findings of cVEMPs (insecure vestibular hearing) and the abnormal findings of sABR (decreased neural synchronization). Comparison of the cVEMPs at affected ears versus unaffected ears and the normal persons revealed significant differences (P < 0.05). Conclusion. Safe vestibular hearing was effective in the improvement of the neural synchronization.

  19. Active control strategy for synchronization and anti-synchronization of a fractional chaotic financial system

    Science.gov (United States)

    Huang, Chengdai; Cao, Jinde

    2017-05-01

    This paper is concerned with the issues of synchronization and anti-synchronization for fractional chaotic financial system with market confidence by taking advantage of active control approach. Some sufficient conditions are derived to guarantee the synchronization and anti-synchronization for the proposed fractional system. Moreover, the relationship between the order and synchronization(anti-synchronization) is demonstrated numerically. It reveals that synchronization(anti-synchronization) is faster as the order increases. Finally, two illustrative examples are exploited to verify the efficiency of the obtained theoretical results.

  20. Synchronization in uncertain complex networks.

    Science.gov (United States)

    Chen, Maoyin; Zhou, Donghua

    2006-03-01

    We consider the problem of synchronization in uncertain generic complex networks. For generic complex networks with unknown dynamics of nodes and unknown coupling functions including uniform and nonuniform inner couplings, some simple linear feedback controllers with updated strengths are designed using the well-known LaSalle invariance principle. The state of an uncertain generic complex network can synchronize an arbitrary assigned state of an isolated node of the network. The famous Lorenz system is stimulated as the nodes of the complex networks with different topologies. We found that the star coupled and scale-free networks with nonuniform inner couplings can be in the state of synchronization if only a fraction of nodes are controlled.

  1. Solitary Wave Generation from Constant Continuous Wave in Asymmetric Oppositely Directed Waveguide Coupler

    Directory of Open Access Journals (Sweden)

    Kazantseva E.V.

    2015-01-01

    Full Text Available In a model which describes asymmetric oppositely directed nonlinear coupler it was observed in numerical simulations a phenomenon of solitary wave generation from the input constant continuous wave set at the entrance of a waveguide with negative refraction. The period of solitary wave formation decreases with increase of the continuum wave amplitude.

  2. Vlasov Simulation of Electrostatic Solitary Structures in Multi-Component Plasmas

    Science.gov (United States)

    Umeda, Takayuki; Ashour-Abdalla, Maha; Pickett, Jolene S.; Goldstein, Melvyn L.

    2012-01-01

    Electrostatic solitary structures have been observed in the Earth's magnetosheath by the Cluster spacecraft. Recent theoretical work has suggested that these solitary structures are modeled by electron acoustic solitary waves existing in a four-component plasma system consisting of core electrons, two counter-streaming electron beams, and one species of background ions. In this paper, the excitation of electron acoustic waves and the formation of solitary structures are studied by means of a one-dimensional electrostatic Vlasov simulation. The present result first shows that either electron acoustic solitary waves with negative potential or electron phase-space holes with positive potential are excited in four-component plasma systems. However, these electrostatic solitary structures have longer duration times and higher wave amplitudes than the solitary structures observed in the magnetosheath. The result indicates that a high-speed and small free energy source may be needed as a fifth component. An additional simulation of a five-component plasma consisting of a stable four-component plasma and a weak electron beam shows the generation of small and fast electron phase-space holes by the bump-on-tail instability. The physical properties of the small and fast electron phase-space holes are very similar to those obtained by the previous theoretical analysis. The amplitude and duration time of solitary structures in the simulation are also in agreement with the Cluster observation.

  3. Rare case of solitary plasmacytoma of the skull in a young male ...

    African Journals Online (AJOL)

    Solitary plasmacytoma of bone without signs of multiple myeloma is a rare entity. It usually presents as an osteolytic lesion in the axial skeleton of an elderly patient. Here, we report a case of solitary plasmacytoma in the skull of a young male patient which emphasises the need to consider it in the differential diagnosis of a ...

  4. Risk factors for renal injury in children with a solitary functioning kidney.

    NARCIS (Netherlands)

    Westland, R.; Kurvers, R.A.; Wijk, J.A. van; Schreuder, M.F.

    2013-01-01

    OBJECTIVE: The hyperfiltration hypothesis implies that children with a solitary functioning kidney are at risk to develop hypertension, proteinuria, and chronic kidney disease. We sought to determine the presenting age of renal injury and identify risk factors for children with a solitary

  5. Solitary cysticercosis of the biceps brachii in a vegetarian: a rare and unusual pseudotumor

    Energy Technology Data Exchange (ETDEWEB)

    Abdelwahab, Ibrahim Fikry [Department of Radiology, New York Methodist Hospital Affiliated with Weill Medical College of Cornell University, 506 Sixth Street, Brooklyn, NY 11215 (United States); Klein, Michael J. [Department of Pathology, Mount Sinai Medical Center, 1 Gustave Levy Place, New York, NY 10029 (United States); Hermann, George [Department of Radiology, Mount Sinai Medical Center, 1 Gustave Levy Place, New York, NY 10029 (United States); Abdul-Quader, Mohammed [Department of Radiology, Columbia Presbyterian Medical Center, 177 Fort Washington Avenue, New York, NY 10032 (United States)

    2003-07-01

    We report a 40-year-old man with cysticercosis presenting as a solitary tumor in the biceps brachii muscle. Physical examination revealed an intramuscular mass and magnetic resonance imaging suggested a cyst. The histologic diagnosis was a cysticercus. Such solitary presentation of muscular cysticercosis is extremely rare with only a handful of sporadic reports in the literature. (orig.)

  6. Differential Properties of Venom Peptides and Proteins in Solitary vs. Social Hunting Wasps

    Science.gov (United States)

    Lee, Si Hyeock; Baek, Ji Hyeong; Yoon, Kyungjae Andrew

    2016-01-01

    The primary functions of venoms from solitary and social wasps are different. Whereas most solitary wasps sting their prey to paralyze and preserve it, without killing, as the provisions for their progeny, social wasps usually sting to defend their colonies from vertebrate predators. Such distinctive venom properties of solitary and social wasps suggest that the main venom components are likely to be different depending on the wasps’ sociality. The present paper reviews venom components and properties of the Aculeata hunting wasps, with a particular emphasis on the comparative aspects of venom compositions and properties between solitary and social wasps. Common components in both solitary and social wasp venoms include hyaluronidase, phospholipase A2, metalloendopeptidase, etc. Although it has been expected that more diverse bioactive components with the functions of prey inactivation and physiology manipulation are present in solitary wasps, available studies on venom compositions of solitary wasps are simply too scarce to generalize this notion. Nevertheless, some neurotoxic peptides (e.g., pompilidotoxin and dendrotoxin-like peptide) and proteins (e.g., insulin-like peptide binding protein) appear to be specific to solitary wasp venom. In contrast, several proteins, such as venom allergen 5 protein, venom acid phosphatase, and various phospholipases, appear to be relatively more specific to social wasp venom. Finally, putative functions of main venom components and their application are also discussed. PMID:26805885

  7. A Rare third ventricle solitary tuberculoma | N'da | Pan African ...

    African Journals Online (AJOL)

    The authors report a case of third ventricle solitary Tuberculoma which has occurred in a 10 year old patient and revealed by a syndrome of intracranial hypertension without tuberculosis stigma. This lesion ... The authors insist on the diagnostic and therapeutic difficulties in front of a third ventricle solitary tuberculoma.

  8. Stability of negative solitary waves for an integrable modified Camassa-Holm equation

    International Nuclear Information System (INIS)

    Yin Jiuli; Tian Lixin; Fan Xinghua

    2010-01-01

    In this paper, we prove that the modified Camassa-Holm equation is Painleve integrable. We also study the orbital stability problem of negative solitary waves for this integrable equation. It is shown that the negative solitary waves are stable for arbitrary wave speed of propagation.

  9. Male solitary drinking and hazardous alcohol use in nine countries of the former Soviet Union.

    Science.gov (United States)

    Stickley, Andrew; Koyanagi, Ai; Roberts, Bayard; Murphy, Adrianna; Kizilova, Kseniya; McKee, Martin

    2015-05-01

    Despite evidence that many people engage in solitary drinking and that it might be associated with negative consequences, to date, little research has focused on this form of drinking behaviour. This study examined the prevalence and factors associated with solitary drinking, and assessed whether it is linked with hazardous alcohol use among males in nine countries of the former Soviet Union (fSU). Data came from a cross-sectional population-based survey undertaken in 2010/11 in Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Russia, and Ukraine. Information was obtained on the frequency of solitary drinking among male regular drinkers (i.e., those consuming alcoholic drinks at least once a month), and on problem drinking (CAGE) and heavy episodic drinking (HED). Logistic regression analysis was used to examine associations between the variables. The prevalence of occasional and frequent solitary drinking ranged from 8.4% (Georgia) to 42.4% (Azerbaijan), and 3.1% (Kazakhstan) to 8.2% (Armenia), respectively. Solitary drinking was associated with being older, divorced/widowed, living alone, having a bad/very bad household financial situation, lower levels of social support, and poor self-rated health. Occasional solitary drinking was linked to problem drinking and HED, while frequent solitary alcohol use was related to problem drinking. Solitary drinking is relatively common among male regular drinkers in the fSU and is linked to older age, social and economic disadvantage, and hazardous alcohol use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Endophenotypes in a Dynamically Connected Brain

    NARCIS (Netherlands)

    Smit, D.J.A.; Boersma, M.; van Beijsterveldt, C.E.M.; Posthuma, D.; Boomsma, D.I.; Stam, C.J.; de Geus, E.J.C.

    2010-01-01

    We examined the longitudinal genetic architecture of three parameters of functional brain connectivity. One parameter described overall connectivity (synchronization likelihood, SL). The two others were derived from graph theory and described local (clustering coefficient, CC) and global (average

  11. Control of non-conventional synchronous motors

    CERN Document Server

    Louis, Jean-Paul

    2013-01-01

    Classical synchronous motors are the most effective device to drive industrial production systems and robots with precision and rapidity. However, numerous applications require efficient controls in non-conventional situations. Firstly, this is the case with synchronous motors supplied by thyristor line-commutated inverters, or with synchronous motors with faults on one or several phases. Secondly, many drive systems use non-conventional motors such as polyphase (more than three phases) synchronous motors, synchronous motors with double excitation, permanent magnet linear synchronous motors,

  12. A synchronous game for binary constraint systems

    Science.gov (United States)

    Kim, Se-Jin; Paulsen, Vern; Schafhauser, Christopher

    2018-03-01

    Recently, Slofstra proved that the set of quantum correlations is not closed. We prove that the set of synchronous quantum correlations is not closed, which implies his result, by giving an example of a synchronous game that has a perfect quantum approximate strategy but no perfect quantum strategy. We also exhibit a graph for which the quantum independence number and the quantum approximate independence number are different. We prove new characterisations of synchronous quantum approximate correlations and synchronous quantum spatial correlations. We solve the synchronous approximation problem of Dykema and the second author, which yields a new equivalence of Connes' embedding problem in terms of synchronous correlations.

  13. Measurement of Ultra-Short Solitary Electromagnetic Pulses

    Directory of Open Access Journals (Sweden)

    Eva Gescheidtova

    2004-01-01

    Full Text Available In connection with the events of the last few years and with the increased number of terrorist activities, the problem of identification and measurement of electromagnetic weapons or other systems impact occurred. Among these are also microwave sources, which can reach extensive peak power of up to Pmax = 100 MW. Solitary, in some cases several times repeated, impulses lasting from tp E <1, 60>ns, cause the destruction of semiconductor junctions. These days we can find scarcely no human activity, where semiconductor structures are not used. The problem of security support of the air traffic, transportation, computer nets, banks, national strategic data canter’s, and other applications crops up. Several types of system protection from the ultra-short electromagnetic pulses present itself, passive and active protection. The analysis of the possible measuring methods, convenient for the identification and measurement of the ultra-short solitary electromagnetic pulses in presented in this paper; some of the methods were chosen and used for practical measurement. This work is part of Research object MSM262200022 "Research of microelectronic systems".

  14. Solitary rectal ulcer syndrome: clinical findings, surgical treatment, and outcomes.

    Science.gov (United States)

    Torres, Carlos; Khaikin, Marat; Bracho, Jorge; Luo, Cheng Hua; Weiss, Eric G; Sands, Dana R; Cera, Susan; Nogueras, Juan J; Wexner, Steven D

    2007-11-01

    Solitary rectal ulcer syndrome (SRUS) is a rare disorder often misdiagnosed as a malignant ulcer. Histopathological features of SRUS are characteristic and pathognomonic; nevertheless, the endoscopic and clinical presentations may be confusing. The aim of the present study was to assess the clinical findings, surgical treatment, and outcomes in patients who suffer from SRUS. A retrospective chart review was undertaken, from January 1989 to May 2005 for all patients who were diagnosed with SRUS. Data recorded included: patient's age, gender, clinical presentation, past surgical history, diagnostic and preoperative workup, operative procedure, complications, and outcomes. During the study period, 23 patients were diagnosed with SRUS. Seven patients received only medical treatment, and in three patients, the ulcer healed after medical treatment. Sixteen patients underwent surgical treatment. In four patients, the symptoms persisted after surgery. Two patients presented with postoperative rectal bleeding requiring surgical intervention. Three patients developed late postoperative sexual dysfunction. One patient continued suffering from rectal pain after a colostomy was constructed. Median follow-up was 14 (range 2-84) months. The results of this study show clearly that every patient with SRUS must be assessed individually. Initial treatment should include conservative measures. In patients with refractory symptoms, surgical treatment should be considered. Results of anterior resection and protocolectomy are satisfactory for solitary rectal ulcer.

  15. Dispersal of solitary bees and bumblebees in a winter oilseed rape field

    DEFF Research Database (Denmark)

    Calabuig, Isabel

    2000-01-01

    Dispersal distributions of solitary bees and bumblebees were studied in a winter oilseed rape field. Window-traps were placed in the rape field along a line transect perpendicular to the field edge. 19 species of solitary bees were recorded and all but four species are polylectic, including...... Brassicaceae as host-plant family. Through non-linear regression, the decline in solitary bee individuals versus distance from field edge significantly fitted a steep two-parameter exponential decay function. Activity of solitary bees was clearly highest within 30 metres from the field edge. Apparently......, solitary bees do not play any noteworthy role in the pollination of winter oilseed rape in Denmark. The traps yielded ten species of bumblebees, and a significant linear correlation was found between numbers of individuals and distance from the field edge. This result is attributed to bumblebee foraging...

  16. Asymptotic expansions for solitary gravity-capillary waves in two and three dimensions

    International Nuclear Information System (INIS)

    Ablowitz, M J; Haut, T S

    2010-01-01

    High-order asymptotic series are obtained for gravity-capillary solitary waves, where the first term in the series is the well-known sech 2 solution of the KdV equation. The asymptotic series is used, with nine terms included, to investigate the effects of surface tension on the height and energy of large amplitude waves, and waves close to the solitary version of Stokes' extreme wave. In particular, for surface tension below a critical value, the solitary wave with the maximum energy is obtained. For large surface tension, the series is also used to study the energy related to the solitary waves of depression. Energy considerations suggest that, for large enough surface tension, there are solitary waves that can get close to the fluid bottom. Comparisons are also made with recent experiments.

  17. Formation and dynamics of electrostatic solitary waves associated with relativistic electron beam

    Science.gov (United States)

    Moslem, W. M.; Bencheriet, F.; Sabry, R.; Djebli, M.

    2012-04-01

    Properties of nonlinear electrostatic solitary waves in a plasma are analyzed by using the hydrodynamic model for electrons, positrons, and relativistic electron beam. For this purpose, the Kadomtsev-Petviashvili (KP) equation has been derived and its analytical solution is presented. It is found that the nonlinear solitary structures can propagate as slow and fast modes. The dependence of these modes on the plasma parameters is defined numerically. Furthermore, positive and negative electrostatic solitary structures can exist. In order to show that the characteristics of the solitary wave profile are influenced by the plasma parameters, the relevant numerical analysis of the KP equation is obtained. The electrostatic solitary waves, as predicted here, may be associated with the nonlinear structures caused by the interaction of relativistic jets with plasma medium, such as in the active galactic nuclei and in the magnetosphere of collapsing stars.

  18. Complex dynamical behaviors of compact solitary waves in the perturbed mKdV equation

    International Nuclear Information System (INIS)

    Yin Jiu-Li; Xing Qian-Qian; Tian Li-Xin

    2014-01-01

    In this paper, we give a detailed discussion about the dynamical behaviors of compact solitary waves subjected to the periodic perturbation. By using the phase portrait theory, we find one of the nonsmooth solitary waves of the mKdV equation, namely, a compact solitary wave, to be a weak solution, which can be proved. It is shown that the compact solitary wave easily turns chaotic from the Melnikov theory. We focus on the sufficient conditions by keeping the system stable through selecting a suitable controller. Furthermore, we discuss the chaotic threshold for a perturbed system. Numerical simulations including chaotic thresholds, bifurcation diagrams, the maximum Lyapunov exponents, and phase portraits demonstrate that there exists a special frequency which has a great influence on our system; with the increase of the controller strength, chaos disappears in the perturbed system. But if the controller strength is sufficiently large, the solitary wave vibrates violently. (general)

  19. Synchronization and a secure communication scheme using optical star network

    Science.gov (United States)

    Jeeva Sathya Theesar, S.; Ariffin, M. R. K.; Banerjee, Santo

    2013-12-01

    This work aims to show the effect of synchronization phenomena in multi-nodal star optical network topology as well as to develop an efficient symmetric cryptosystem utilizing available parameters. The optical network is based on chaotic semiconductor laser (SL) systems described by dimensionless modified Lang-Kobayashi's (L-K) delay differential equations. The network nodes are mutually connected with a central semiconductor laser hub with bidirectional linear optical feedback. It has been observed that the laser output can be modulated using a star network setup. The laser intensity increases with the number of nodes and its much more higher than the same for solitary laser, keeping all other inputs as constant. So the network topology is an effective way to optimize the output power. The process by each nodes into the network is illustrated graphically for three, five and seven SLs, respectively. Also the whole network can be implemented as an optical communication system for transmission of signals. Each SL can act as a transceiver during communication. The communication process is examined using a chaotic signal as a plaintext connected with the SL hub and successfully provided a symmetrically secure mechanism upon the communication protocol. The result shows the optimization of output power with the increment of the number of nodes. Also the communication scheme can successfully decode the encrypted signal from SL Hub, at each other nodes.

  20. Synchronizing Strategies under Partial Observability

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Laursen, Simon; Srba, Jiri

    2014-01-01

    Embedded devices usually share only partial information about their current configurations as the communication bandwidth can be restricted. Despite this, we may wish to bring a failed device into a given predetermined configuration. This problem, also known as resetting or synchronizing words, has...

  1. Synchronizing Web Documents with Style

    NARCIS (Netherlands)

    R.L. Guimarães (Rodrigo); D.C.A. Bulterman (Dick); P.S. Cesar Garcia (Pablo Santiago); A.J. Jansen (Jack)

    2014-01-01

    htmlabstractIn this paper we report on our efforts to define a set of document extensions to Cascading Style Sheets (CSS) that allow for structured timing and synchronization of elements within a Web page. Our work considers the scenario in which the temporal structure can be decoupled from the

  2. Learning through synchronous electronic discussion

    NARCIS (Netherlands)

    Kanselaar, G.; Veerman, A.L.; Andriessen, J.E.B.

    2000-01-01

    This article reports a study examining university student pairs carrying out an electronic discussion task in a synchronous computer mediated communication (CMC) system (NetMeeting). The purpose of the assignment was to raise students' awareness concerning conceptions that characterise effective

  3. OVULATORY RESFONSE IN PROGESTERONE SYNCHRONIZED ...

    African Journals Online (AJOL)

    Conception rate and ovarian function following estrus control by progestetone injections in dairy cattle. J. Anim. Sci. 14, 224. VAN NIEKERK, C.H., BELONJE, P.C. & SPREETH, E.B., 1970. Post partum synchronization of the oestrus period of lactating friesland cows with 6-methyl-17-acetozy-Progesterone. (MAP) and PMSG.

  4. Sports Medicine Meets Synchronized Swimming.

    Science.gov (United States)

    Wenz, Betty J.; And Others

    This collection of articles contains information about synchronized swimming. Topics covered include general physiology and cardiovascular conditioning, flexibility exercises, body composition, strength training, nutrition, coach-athlete relationships, coping with competition stress and performance anxiety, and eye care. Chapters are included on…

  5. Generalized synchronization via impulsive control

    International Nuclear Information System (INIS)

    Zhang Rong; Xu Zhenyuan; Yang, Simon X.; He Xueming

    2008-01-01

    This paper demonstrates theoretically that two completely different systems can implement GS via impulsive control, moreover by using impulsive control, for a given manifold y = H(x) we construct a response system to achieve GS with drive system and the synchronization manifold is y = H(x). Our theoretical results are supported by numerical examples

  6. Epidemic Synchronization in Robotic Swarms

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Nielsen, Jens Frederik Dalsgaard; Ngo, Trung Dung

    2009-01-01

    Clock synchronization in swarms of networked mobile robots is studied in a probabilistic, epidemic framework. In this setting communication and synchonization is considered to be a randomized process, taking place at unplanned instants of geographical rendezvous between robots. In combination...... as an infinite-dimensional optimal controlproblem. Illustrative numerical examples are given and commented....

  7. Main injector synchronous timing system

    International Nuclear Information System (INIS)

    Blokland, W.; Steimel, J.

    1998-01-01

    The Synchronous Timing System is designed to provide sub-nanosecond timing to instrumentation during the acceleration of particles in the Main Injector. Increased energy of the beam particles leads to a small but significant increase in speed, reducing the time it takes to complete a full turn of the ring by 61 nanoseconds (or more than 3 rf buckets). In contrast, the reference signal, used to trigger instrumentation and transmitted over a cable, has a constant group delay. This difference leads to a phase slip during the ramp and prevents instrumentation such as dampers from properly operating without additional measures. The Synchronous Timing System corrects for this phase slip as well as signal propagation time changes due to temperature variations. A module at the LLRF system uses a 1.2 Gbit/s G-Link chip to transmit the rf clock and digital data (e.g. the current frequency) over a single mode fiber around the ring. Fiber optic couplers at service buildings split off part of this signal for a local module which reconstructs a synchronous beam reference signal. This paper describes the background, design and expected performance of the Synchronous Timing System. copyright 1998 American Institute of Physics

  8. Main injector synchronous timing system

    International Nuclear Information System (INIS)

    Blokland, Willem; Steimel, James

    1998-01-01

    The Synchronous Timing System is designed to provide sub-nanosecond timing to instrumentation during the acceleration of particles in the Main Injector. Increased energy of the beam particles leads to a small but significant increase in speed, reducing the time it takes to complete a full turn of the ring by 61 nanoseconds (or more than 3 rf buckets). In contrast, the reference signal, used to trigger instrumentation and transmitted over a cable, has a constant group delay. This difference leads to a phase slip during the ramp and prevents instrumentation such as dampers from properly operating without additional measures. The Synchronous Timing System corrects for this phase slip as well as signal propagation time changes due to temperature variations. A module at the LLRF system uses a 1.2 Gbit/s G-Link chip to transmit the rf clock and digital data (e.g. the current frequency) over a single mode fiber around the ring. Fiber optic couplers at service buildings split off part of this signal for a local module which reconstructs a synchronous beam reference signal. This paper describes the background, design and expected performance of the Synchronous Timing System

  9. Synchronized whistlers recorded at Varanasi

    Indian Academy of Sciences (India)

    An attempt has been made to explain the dynamic spectra using lightning discharge generated from magnetospheric sources. Keywords. Whistler-mode wave propagation; dispersion; synchronized whistler. PACS No. 94.20.Mm. It is well-known that electromagnetic waves in wide frequency range are associated with.

  10. Fermi Timing and Synchronization System

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, R.; Staples, J.; Doolittle, L.; Byrd, J.; Ratti, A.; Kaertner, F.X.; Kim, J.; Chen, J.; Ilday, F.O.; Ludwig, F.; Winter, A.; Ferianis, M.; Danailov, M.; D' Auria, G.

    2006-07-19

    The Fermi FEL will depend critically on precise timing of its RF, laser and diagnostic subsystems. The timing subsystem to coordinate these functions will need to reliably maintain sub-100fs synchronicity between distant points up to 300m apart in the Fermi facility. The technology to do this is not commercially available, and has not been experimentally demonstrated in a working facility. Therefore, new technology must be developed to meet these needs. Two approaches have been researched by different groups working with the Fermi staff. At MIT, a pulse transmission scheme has been developed for synchronization of RF and laser devices. And at LBL, a CW transmission scheme has been developed for RF and laser synchronization. These respective schemes have advantages and disadvantages that will become better understood in coming years. This document presents the work done by both teams, and suggests a possible system design which integrates them both. The integrated system design provides an example of how choices can be made between the different approaches without significantly changing the basic infrastructure of the system. Overall system issues common to any synchronization scheme are also discussed.

  11. Neural synchronization via potassium signaling

    DEFF Research Database (Denmark)

    Postnov, Dmitry E; Ryazanova, Ludmila S; Mosekilde, Erik

    2006-01-01

    Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...

  12. Neural Synchronization via Potassium Signaling,

    DEFF Research Database (Denmark)

    Postnov, D. E.; Ryazanova, L. S.; Sosnovtseva, Olga

    2006-01-01

    Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...

  13. Digital device for synchronous storage

    International Nuclear Information System (INIS)

    Kobzar', Yu.M.; Kovtun, V.G.; Pashechko, N.I.

    1991-01-01

    Synchronous storage digital device for IR electron-photon emission spectrometer operating with analogue-to-digital converter F4223 or monocrystal converter K572PV1 is described. The device accomplished deduction of noise-background in each storage cycle. Summation and deduction operational time equals 90 ns, device output code discharge - 20, number of storages -2 23

  14. Research on bit synchronization based on GNSS

    Science.gov (United States)

    Yu, Huanran; Liu, Yi-jun

    2017-05-01

    The signals transmitted by GPS satellites are divided into three components: carrier, pseudocode and data code. The processes of signal acquisition are acquisition, tracking, bit synchronization, frame synchronization, navigation message extraction, observation extraction and position speed calculation, among which bit synchronization is of greatest importance. The accuracy of bit synchronization and the shortening of bit synchronization time can help us to use satellite to realize positioning and acquire the information transmitted by satellite signals more accurately. Even under the condition of weak signal, how to improve bit synchronization performance is what we need to research. We adopt a method of polymorphic energy accumulation minima so as to find the bit synchronization point, as well as complete the computer simulation to conclude that under the condition of extremely weak signal power, this method still has superior synchronization performance, which can achieve high bit edge detection rate and the optimal bit error rate.

  15. Pinning Synchronization of Switched Complex Dynamical Networks

    Directory of Open Access Journals (Sweden)

    Liming Du

    2015-01-01

    Full Text Available Network topology and node dynamics play a key role in forming synchronization of complex networks. Unfortunately there is no effective synchronization criterion for pinning synchronization of complex dynamical networks with switching topology. In this paper, pinning synchronization of complex dynamical networks with switching topology is studied. Two basic problems are considered: one is pinning synchronization of switched complex networks under arbitrary switching; the other is pinning synchronization of switched complex networks by design of switching when synchronization cannot achieved by using any individual connection topology alone. For the two problems, common Lyapunov function method and single Lyapunov function method are used respectively, some global synchronization criteria are proposed and the designed switching law is given. Finally, simulation results verify the validity of the results.

  16. Synchronization of linear systems via relative actuation

    OpenAIRE

    Tuna, S. Emre

    2016-01-01

    Synchronization in networks of discrete-time linear time-invariant systems is considered under relative actuation. Neither input nor output matrices are assumed to be commensurable. A distributed algorithm that ensures synchronization via dynamic relative output feedback is presented.

  17. A Novel Synchronization-Based Approach for Functional Connectivity Analysis

    Directory of Open Access Journals (Sweden)

    Angela Lombardi

    2017-01-01

    Full Text Available Complex network analysis has become a gold standard to investigate functional connectivity in the human brain. Popular approaches for quantifying functional coupling between fMRI time series are linear zero-lag correlation methods; however, they might reveal only partial aspects of the functional links between brain areas. In this work, we propose a novel approach for assessing functional coupling between fMRI time series and constructing functional brain networks. A phase space framework is used to map couples of signals exploiting their cross recurrence plots (CRPs to compare the trajectories of the interacting systems. A synchronization metric is extracted from the CRP to assess the coupling behavior of the time series. Since the functional communities of a healthy population are expected to be highly consistent for the same task, we defined functional networks of task-related fMRI data of a cohort of healthy subjects and applied a modularity algorithm in order to determine the community structures of the networks. The within-group similarity of communities is evaluated to verify whether such new metric is robust enough against noise. The synchronization metric is also compared with Pearson’s correlation coefficient and the detected communities seem to better reflect the functional brain organization during the specific task.

  18. Increased entorhinal-prefrontal theta synchronization parallels decreased entorhinal-hippocampal theta synchronization during learning and consolidation of associative memory.

    Directory of Open Access Journals (Sweden)

    Kaori eTakehara-Nishiuchi

    2012-01-01

    Full Text Available Memories are thought to be encoded as a distributed representation in the neocortex. The medial prefrontal cortex (mPFC has been shown to support the expression of memories that initially depend on the hippocampus (HPC, yet the mechanisms by which the HPC and mPFC access the distributed representations in the neocortex are unknown. By measuring phase synchronization of local field potential (LFP oscillations, we found that learning initiated changes in neuronal communication of the HPC and mPFC with the lateral entorhinal cortex (LEC, an area that is connected with many other neocortical regions. LFPs were recorded simultaneously from the three brain regions while rats formed an association between an auditory stimulus (CS and eyelid stimulation (US in a trace eyeblink conditioning paradigm, as well as during retention one month following learning. Over the course of learning, theta oscillations in the LEC and mPFC became strongly synchronized following the presentation of the CS on trials in which rats exhibited a conditioned response (CR, and this strengthened synchronization was also observed during retention one month after learning. In contrast, CS-evoked theta synchronization between the LEC and HPC decreased with learning. Our results suggest that the communication between the LEC and mPFC is strengthened with learning whereas the communication between the LEC and HPC is concomitantly weakened, suggesting that enhanced LEC-mPFC communication may be a key process for theoretically-proposed neocortical reorganization accompanying encoding and consolidation of a memory.

  19. Synchronization of coupled chaotic dynamics on networks

    Indian Academy of Sciences (India)

    We review some recent work on the synchronization of coupled dynamical systems on a variety of networks. When nodes show synchronized behaviour, two ... [5], congregations of synchronously flashing fireflies [6], and cricket that chirp in unison [7]. Coupled oscillators were first studied by Winfree [8] and Kuramoto [9].

  20. Synchronization of coupled nonidentical multidelay feedback systems

    International Nuclear Information System (INIS)

    Hoang, Thang Manh; Nakagawa, Masahiro

    2007-01-01

    We present the lag synchronization of coupled nonidentical multidelay feedback systems, in which the synchronization signal is the sum of nonlinearly transformed components of delayed state variable. The sufficient condition for synchronization is considered by the Krasovskii-Lyapunov theory. The specific examples will demonstrate and verify the effectiveness of the proposed model

  1. Two novel synchronization criterions for a unified chaotic system

    International Nuclear Information System (INIS)

    Tao Chaohai; Xiong Hongxia; Hu Feng

    2006-01-01

    Two novel synchronization criterions are proposed in this paper. It includes drive-response synchronization and adaptive synchronization schemes. Moreover, these synchronization criterions can be applied to a large class of chaotic systems and are very useful for secure communication

  2. Dynamical aspects of various solitary waves and double layers in dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Das, G.C. [Plasma Physics Division, Institute of Advanced Study in Science Technology, Khanapara, Guwahati-781022, Assam (India); Sarma, J. [Department of Mathematics, R. G. Baruah College, Guwahati-781025, Assam (India); Talukdar, M. [Computer Science Division, Institute of Advanced Study in Science Technology, Khanapara, Guwahati-781022, Assam (India)

    1998-01-01

    Employing quasipotential analysis, the Sagdeev potential equation has been derived in a multicomponent plasma consisting of free and trapped electrons and contaminated by the dust charged grains forming therein by the attachment of electrons to finite-size dust particles. Because of the free and trapped electrons in the dusty plasma, the plasma-acoustic wave exhibits the different features of various solitary waves. The Sagdeev potential equation, at a small-amplitude approximation, leads to the evaluation, by a proposed new formalism of a simple wave solution technique, of the new scenario of solitary wave propagation in a dusty plasma. It has been shown that the ordering of the nonisothermality in the dusty plasma also plays a unique role. In the case of a plasma with first-order nonisothermality, the Sagdeev potential equation derives the compressive solitary wave propagation, while for plasma with higher-order nonisothermality the method might fail to solve the Sagdeev potential equation and, thus, an alternate method is used to reveal the coexistence of compressive and rarefactive solitary waves. In addition, for certain plasma parameters, the solitary waves disappear and a double layer is expected. Again, with the better approximation in the Sagdeev potential, more features of solitary waves, known as spiky and explosive, along with the double layers, are also highlighted. The observations made of the solitary waves could be of further interest in the understanding of laboratory and space plasmas.{copyright} {ital 1998 American Institute of Physics.}

  3. Young children's preference for solitary play: Implications for socio-emotional and school adjustment.

    Science.gov (United States)

    Ooi, Laura L; Baldwin, Danielle; Coplan, Robert J; Rose-Krasnor, Linda

    2018-01-22

    The purpose of this study was to provide additional psychometric support for the Preference for Solitary Play Interview (PSPI) and to examine the associations between self-reported preference for solitary play and indices of adjustment in early childhood. Participants were N = 340 children attending kindergarten and grade 1. Children completed the PSPI, and teachers provided assessments of children's socio-emotional and school adjustment. In support of the validity of the PSPI, preference for solitary play was positively associated with asocial behaviours. Further, preference for solitary play displayed an indirect (but not direct) association with peer exclusion via asocial behaviours. Findings are discussed in terms of the social and behavioural implications of preference for solitary play in early childhood. Statement of contribution What is already known on this subject? Children who spend more time alone are at increased risk of adjustment difficulties. However, some individuals desire to spend time alone because of an appreciation for solitude. A preference for solitude is not associated with negative adjustment in adults and older youth. What does this study add? This study is among the first to examine self-reported preference for solitary in early childhood. Preference for solitude may not be related to emotional or school difficulties in young children. However, a heightened display of solitary behaviours may still evoke negative responses from peers. © 2018 The British Psychological Society.

  4. Solitary plexiform neurofibroma determining pyloric obstruction: a case report

    Directory of Open Access Journals (Sweden)

    Eduardo Cambruzzi

    2014-06-01

    Full Text Available Solitary gastric plexiform neurofibroma (PN is a very rare tumor that originates from the peripheral nerves. PN is a rare cause of pyloric obstruction. A 58 year-old man, reported epigastric discomfort, nausea, and vomiting for two months. Upper digestive endoscopy showed a moderate/accentuated pyloric stenosis. Computed tomography (CT and echoendoscopy revealed a pyloric nodule. The patient underwent to distal gastrectomy. Macroscopically, a gray nodule measuring 1.1 × 1.0 × 1.0 cm was identified. Using microscopy, a benign tumor composed of enlarged tortuous nerve fascicles showing a neurofibromatous proliferation with mild atypia and myxoid matrix was found. The lesion showed positive immunoexpression for S100, Leu7, and epithelial membrane antigen (EMA, and was negative for CD117, DOG-1, desmin, and smooth muscle actin. The diagnosis of PN was then determined.

  5. Solitary rectal ulcer syndrome in children and adolescents.

    Science.gov (United States)

    Perito, Emily R; Mileti, Elizabeth; Dalal, Deepal H; Cho, Soo-Jin; Ferrell, Linda D; McCracken, Marjorie; Heyman, Melvin B

    2012-02-01

    The aim of this study was to describe the presenting symptoms, endoscopic and histologic findings, and clinical courses of pediatric patients diagnosed with solitary rectal ulcer syndrome (SRUS). We describe 15 cases of SRUS diagnosed at our institution during a 13-year period. Cases were identified by review of a pathology database and chart review and confirmed by review of biopsies. Data were collected by retrospective chart review. Presenting symptoms were consistent but nonspecific, most commonly including blood in stools, diarrhea alternating with constipation, and abdominal/perianal pain. Fourteen of 15 patients had normal hemoglobin/hematocrit, erythrocyte sedimentation rate, and albumin at diagnosis. Endoscopic findings, all limited to the distal rectum, ranged from erythema to ulceration and polypoid lesions. Histology revealed characteristic findings. Stool softeners and mesalamine suppositories improved symptoms, but relapse was common. SRUS in children presents with nonspecific symptoms and endoscopic findings. Clinical suspicion is required, and diagnosis requires histologic confirmation. Response to present treatments is variable.

  6. Solitary Large Intestinal Diverticulitis in Leatherback Turtles (Dermochelys coriacea).

    Science.gov (United States)

    Stacy, B A; Innis, C J; Daoust, P-Y; Wyneken, J; Miller, M; Harris, H; James, M C; Christiansen, E F; Foley, A

    2015-07-01

    Leatherback sea turtles are globally distributed and endangered throughout their range. There are limited data available on disease in this species. Initial observations of solitary large intestinal diverticulitis in multiple leatherbacks led to a multi-institutional review of cases. Of 31 subadult and adult turtles for which complete records were available, all had a single exudate-filled diverticulum, as large as 9.0 cm in diameter, arising from the large intestine immediately distal to the ileocecal junction. All lesions were chronic and characterized by ongoing inflammation, numerous intralesional bacteria, marked attenuation of the muscularis, ulceration, and secondary mucosal changes. In three cases, Morganella morganii was isolated from lesions. Diverticulitis was unrelated to the cause of death in all cases, although risk of perforation and other complications are possible. © The Author(s) 2014.

  7. A Rare Differential Diagnosis of a Solitary Anterior Neck Mass

    Directory of Open Access Journals (Sweden)

    Jeyasakthy Saniasiaya

    2016-09-01

    Full Text Available Patients with anterior neck masses commonly present to otorhinolaryngology clinics, but there are limited differential diagnoses for such lesions. Common ones include thyroid nodule and thyroglossal duct cyst. In an elderly patient, a differentiated thyroid carcinoma should be suspected especially if it moves with swallowing. We encountered a typical presentation of a solitary thyroid nodule-like mass with the exception of pulsation in a 65-year-old female. Further investigation, using neck ultrasonography, revealed that it was a variant of right common carotid artery arising from the left common carotid artery. Knowledge of such variants is of great importance as ignorance of such a variation may lead to inadvertent surgical complications during procedures.

  8. Flow and sediment transport induced by a plunging solitary wave

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Sen, M.Berke; Karagali, Ioanna

    2011-01-01

    affected, by as much as a factor of 2, in the runup and hydraulic jump stages. The pore-water pressure measurements showed that the sediment at (or near) the surface of the bed experiences upward-directed pressure gradient forces during the downrush phase. The magnitude of this force can reach values......Two parallel experiments involving the evolution and runup of plunging solitary waves on a sloping bed were conducted: (1) a rigid-bed experiment, allowing direct (hot film) measurements of bed shear stresses, and (2) a sediment-bed experiment, allowing for the measurement of pore-water pressures...... is explained qualitatively in terms of the measured bed shear stress and the pressure gradient forces....

  9. The imaging diagnosis of costal solitary eosinophilic granuloma

    International Nuclear Information System (INIS)

    Cui Fa; Feng Shiting

    2007-01-01

    Objective: To study the imaging features of costal eosinophilic granuloma so as to improve diagnosis accuracy of the disease. Methods: The clinical and imaging materials of 6 patients with costal solitary eosinophilic granuloma which were proved by surgery or histopathology were analyzed retrospectively. X-ray plain films were performed in all the cases, CT in 3 cases, 2 cases were received CT plain scan and I case received both CT plain scan and enhanced CT scan. Results: 4 cases of them located in the anterior ribs. All the lesions were round-like and 5 were single cavity and 1 was multiple cavities. 3 of them were expansile destruction and 3 were cystic destruction. Soft tissue mass around the lesion was identified. Conclusion: X-ray plain films integrating CT play an important role in diagnosis and differential diagnosis of the costal eosinophilic granuloma. (authors)

  10. Sadness and happiness are amplified in solitary listening to music.

    Science.gov (United States)

    Zhang, Jinfan; Yang, Taoxi; Bao, Yan; Li, Hui; Pöppel, Ernst; Silveira, Sarita

    2018-02-01

    Previous studies have shown that music is a powerful means to convey affective states, but it remains unclear whether and how social context shape the intensity and quality of emotions perceived in music. Using a within-subject design, we studied this question in two experimental settings, i.e. when subjects were alone versus in company of others without direct social interaction or feedback. Non-vocal musical excerpts of the emotional qualities happiness or sadness were rated on arousal and valence dimensions. We found evidence for an amplification of perceived emotion in the solitary listening condition, i.e. happy music was rated as happier and more arousing when nobody else was around and, in an analogous manner, sad music was perceived as sadder. This difference might be explained by a shift of attention in the presence of others. The observed interaction of perceived emotion and social context did not differ for stimuli of different cultural origin.

  11. Scattering of quantized solitary waves in the cubic Schrodinger equation

    International Nuclear Information System (INIS)

    Dolan, L.

    1976-01-01

    The quantum mechanics for N particles interacting via a delta-function potential in one space dimension and one time dimension is known. The second-quantized description of this system has for its Euler-Lagrange equations of motion the cubic Schrodinger equation. This nonlinear differential equation supports solitary wave solutions. A quantization of these solitons reproduces the weak-coupling limit to the known quantum mechanics. The phase shift for two-body scattering and the energy of the N-body bound state is derived in this approximation. The nonlinear Schrodinger equation is contrasted with the sine-Gordon theory in respect to the ideas which the classical solutions play in the description of the quantum states

  12. Solitary, spontaneous cervical and large bone fractures in aluminium osteodystrophy

    International Nuclear Information System (INIS)

    Sundaram, M.; Dessner, D.; Ballal, S.

    1991-01-01

    Aluminum-induced bone disease in uremic patients receiving dialysis was first described a little more than 10 years ago. The epidemic form of the disease was seen in centers where there was a high aluminum content in the water dialysate. Although this problem has been corrected, sporadic forms of the disease continue to be noted in dialyzed and nondialyzed patients. Multiple fractures are a radiological feature of aluminum-related bone disease. We present four patients whose nontraumatic fractures involved large bones, without evidence of multiple fractures. Healing was not seen in any of the fractures. In patients receiving dialysis the presence of spontaneous fractures of large bones or cervical vertebrae, which may be clinically silent or vaguely symptomatic, should raise the possibility of aluminum-induced osteomalacia even if these fractures are solitary. (orig./GDG)

  13. Solitary fibrous tumor of the liver: a case report

    Directory of Open Access Journals (Sweden)

    Ying Li-Xiong

    2011-03-01

    Full Text Available Abstract Hepatic solitary fibrous tumor (SFT is a rare tumor originating from the mesenchyme. Here we report a new case of SFT in the liver and review the clinical presentation, radiological and operative findings, diagnosis, treatment, and outcome. The patient was a 59-year-old man who presented with progressive fatigue for 3 months and an abdominal mass for 3 days. On laboratory tests, no abnormality was detected except that abdominal ultrasonography revealed a 9.0 × 6.2 cm hypoechogenic mass in the left lobe of the liver. A computed tomographic scan confirmed a hypodense lesion in the left lobe of the liver. The patient underwent left hepatectomy. SFT was diagnosed on the basis of histopathological findings. The patient was free from all symptoms and had no signs of local recurrence after 24 months' follow up.

  14. Giant Solitary Fibrous Tumor of the Parotid Gland

    Directory of Open Access Journals (Sweden)

    Octavian Chis

    2014-01-01

    Full Text Available Solitary fibrous tumors (SFTs are rare tumors that are mostly found arising from the pleura. SFT of the parotid gland is a rare tumor; only a few cases have been described in the literature. SFTs are benign in most cases. Clinically, SFTs usually manifest as well circumscribed, slow-growing, smooth, and painless masses. CT-Scan and MRI are the most sensitive imaging procedures used. The treatment of choice is complete surgical excision of the lesion. Since recurrence and metastasis can take place after several years, a lifelong clinical and imaging regular follow-up is compulsory. In this paper, we describe the diagnostic and therapeutic challenges of the up-to-now biggest parotid SFT. The clinical presentation, surgical management, and pathological and immunohistochemistry findings are described.

  15. Solitary fibrous tumor of the pleura: 3 case reports

    Directory of Open Access Journals (Sweden)

    Elias Amorim

    2015-06-01

    Full Text Available Summary Introduction: solitary fibrous tumor of the pleura (SFTP is a rare tumor arising from mesenchymatous cells in submesothelial pleural tissue which, unlike mesothelioma, is not related to asbestos or smoking. Methods: report of four patients who underwent surgical treatment for giant SFTP and review of the pertinent literature. Results: of the four patients operated, two presented symptoms including cough, chest pain and feeling of compression, whereas the other two subjects were asymptomatic. All patients underwent complete surgical resection by wide posterolateral thoracotomy, and surgical specimens removed with minimum bleeding. None of the cases required complementary lobectomy or segmentectomy. All tumors were histologically benign. Conclusion: complete resection of the lesion is the treatment of choice in all SFTP cases. Prognosis of the benign lesion is excellent, although close follow-up is necessary. In the rarer, more aggressive forms, treatment may be complemented by adjunctive chemotherapy or radiotherapy, the benefits of which have yet to be confirmed.

  16. Rotating solitary wave at the wall of a cylindrical container

    KAUST Repository

    Amaouche, Mustapha

    2013-04-30

    This paper deals with the theoretical modeling of a rotating solitary surface wave that was observed during water drainage from a cylindrical reservoir, when shallow water conditions were reached. It represents an improvement of our previous study, where the radial flow perturbation was neglected. This assumption led to the classical planar Korteweg–de Vries equation for the wall wave profile, which did not account for the rotational character of the base flow. The present formulation is based on a less restricting condition and consequently corrects the last shortcoming. Now the influence of the background flow appears in the wave characteristics. The theory provides a better physical depiction of the unique experiment by predicting fairly well the wave profile at least in the first half of its lifetime and estimating the speed of the observed wave with good accuracy.

  17. Hypoglyceamia in a Patient with a Solitary Fibrous Tumour

    Directory of Open Access Journals (Sweden)

    Andrew Okpe

    2016-04-01

    Full Text Available Objective: To illustrate an unusual mechanism causing hypoglycaemia. Material and methods: A 76-year-old man presented with episodes of agitation and confusion and was resuscitated with oral glucose gel when found to be hypoglycaemic. Results: A CT scan for an abdominal mass confirmed a solitary fibrous tumour (SFT. The sarcoma multidisciplinary team suggested conservative management. The patient's episodic hypoglycaemia was managed with diet modification including corn-based starch, scheduled snacks and dexamethasone. Glucose levels were within normal range at discharge from hospital. The patient was referred to the palliative care team for follow-up. Conclusion: SFTs causing non-islet cell tumour hypoglycaemia are difficult to treat.

  18. SOLITARY SPLENIC METASTASIS OF COLON CANCER: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Sh. Hashemzadeh M. Safari

    2004-11-01

    Full Text Available Although splenic metastasis is fairly common in disseminated cancer, solitary splenic metastasis in the absence of diffuse dissemination is rare. We report a case of 44 year-old man who developed isolated splenic metastasis of colon cancer. The patient had undergone right sided hemicolectomy for colon cancer in 1988. In 2001, he underwent reoperation because of local recurrence of tumor in the anastomotic site. The patient was admitted to our hospital on Sep 2003 with abdominal pain. Chest X-ray was normal. Abdominal CT scan showed a large cystic lesion in the spleen. Splenectomy was performed for the patient. The spleen was enlarged, firm and irregular. Histological examination showed metastatic mucinous adenocarcinoma. Based on this case, we recommend that clinicians consider possibility of metastasis in cystic lesions of spleen, especially in patients with a history of a malignant disease.

  19. Cramped synchronized general movements in preterm infants as an early marker for cerebral palsy.

    Science.gov (United States)

    Ferrari, Fabrizio; Cioni, Giovanni; Einspieler, Christa; Roversi, M Federica; Bos, Arend F; Paolicelli, Paola B; Ranzi, Andrea; Prechtl, Heinz F R

    2002-05-01

    To ascertain whether specific abnormalities (ie, cramped synchronized general movements [GMs]) can predict cerebral palsy and the severity of later motor impairment in preterm infants affected by brain lesions. Traditional neurological examination was performed, and GMs were serially videotaped and blindly observed for 84 preterm infants with ultrasound abnormalities from birth until 56 to 60 weeks' postmenstrual age. The developmental course of GM abnormalities was compared with brain ultrasound findings alone and with findings from neurological examination, in relation to the patient's outcome at age 2 to 3 years. Infants with consistent or predominant (33 cases) cramped synchronized GMs developed cerebral palsy. The earlier cramped synchronized GMs were observed, the worse was the neurological outcome. Transient cramped synchronized character GMs (8 cases) were followed by mild cerebral palsy (fidgety movements were absent) or normal development (fidgety movements were present). Consistently normal GMs (13 cases) and poor repertoire GMs (30 cases) either lead to normal outcomes (84%) or cerebral palsy with mild motor impairment (16%). Observation of GMs was 100% sensitive, and the specificity of the cramped synchronized GMs was 92.5% to 100% throughout the age range, which is much higher than the specificity of neurological examination. Consistent and predominant cramped synchronized GMs specifically predict cerebral palsy. The earlier this characteristic appears, the worse is the later impairment.

  20. Systemic therapy for brain metastases.

    Science.gov (United States)

    Venur, Vyshak Alva; Karivedu, Vidhya; Ahluwalia, Manmeet S

    2018-01-01

    Central nervous system metastases cause grave morbidity in patients with advanced malignancies. Lung cancer, breast cancer, and melanoma are the three most common causes of brain metastases. Although the exact incidence of brain metastases is unclear, there appears to be an increasing incidence which has been attributed to longer survival, better control of systemic disease, and better imaging modalities. Until recently surgical resection of solitary or symptomatic brain metastases, and radiation therapy (either whole-brain radiation therapy or stereotactic radiation) were the mainstay of treatment for patients with brain metastases. The majority of traditional chemotherapies have shown limited activity in the central nervous system, which has been attributed to the blood-brain barrier and the molecular structure of the used agents. The discovery of driver mutations and drugs targeting these mutations has changed the treatment landscape. Several of these targeted small-molecule tyrosine kinase inhibitors do cross the blood-brain barrier and/or have shown activity in the central nervous system. Another major advance in the care of brain metastases has been the advent of new immunotherapeutic agents, for which initial studies have shown intracranial activity. In this chapter, we will review the unique challenges in the treatment of brain metastases. The pertinent clinical studies of chemotherapy in brain metastases will be discussed. The currently reported clinical trials and evidence for use of targeted therapies and immunotherapeutic agents will be emphasized. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Fast Self-Synchronization between LowVoltage Microgrid and Inverter using Virtual Synchronous Converter

    OpenAIRE

    Md Ruhul Amin; Shamsul Aizam Zulkifli

    2017-01-01

    In this paper, a fast self-synchronization known as virtual synchronous converter (VSCon) between single-phase microgrid and inverter in low-voltage microgrid, has been developed in Matlab/Simulink. The idea is to any phase locked loop (PLL) circuit for inverter-microgrid synchronization in order to improve the synchronization time. As known, it is difficult and lengthy process to tune the PLL gain parameters to reach suitable performance for synchronizing among the voltage, phase-angle and f...

  2. Optimal transient growth in thin-interface internal solitary waves

    Science.gov (United States)

    Passaggia, Pierre-Yves; Helfrich, Karl R.; White, Brian L.

    2018-04-01

    The dynamics of perturbations to large-amplitude Internal Solitary Waves (ISW) in two-layered flows with thin interfaces is analyzed by means of linear optimal transient growth methods. Optimal perturbations are computed through direct-adjoint iterations of the Navier-Stokes equations linearized around inviscid, steady ISWs obtained from the Dubreil-Jacotin-Long (DJL) equation. Optimal perturbations are found as a function of the ISW phase velocity $c$ (alternatively amplitude) for one representative stratification. These disturbances are found to be localized wave-like packets that originate just upstream of the ISW self-induced zone (for large enough $c$) of potentially unstable Richardson number, $Ri < 0.25$. They propagate through the base wave as coherent packets whose total energy gain increases rapidly with $c$. The optimal disturbances are also shown to be relevant to DJL solitary waves that have been modified by viscosity representative of laboratory experiments. The optimal disturbances are compared to the local WKB approximation for spatially growing Kelvin-Helmholtz (K-H) waves through the $Ri < 0.25$ zone. The WKB approach is able to capture properties (e.g., carrier frequency, wavenumber and energy gain) of the optimal disturbances except for an initial phase of non-normal growth due to the Orr mechanism. The non-normal growth can be a substantial portion of the total gain, especially for ISWs that are weakly unstable to K-H waves. The linear evolution of Gaussian packets of linear free waves with the same carrier frequency as the optimal disturbances is shown to result in less energy gain than found for either the optimal perturbations or the WKB approximation due to non-normal effects that cause absorption of disturbance energy into the leading face of the wave.

  3. Solitary Waves of Ice Loss Detected in Greenland Crustal Motion

    Science.gov (United States)

    Adhikari, S.; Ivins, E. R.; Larour, E. Y.

    2017-12-01

    The annual cycle and secular trend of Greenland mass loading are well recorded in measurements of solid Earth deformation. While bedrock vertical displacements are in phase with loading as inferred from space observations, horizontal motions have received almost no attention. The horizontal bedrock displacements can potentially track the spatiotemporal detail of mass changes with great fidelity. Our analysis of Greenland crustal motion data reveals that a significant excitation of horizontal amplitudes occurs during the intense Greenland melting. A suite of space geodetic observations and climate reanalysis data cannot explain these large horizontal displacements. We discover that solitary seasonal waves of substantial mass transport traveled through Rink Glacier in 2010 and 2012. We deduce that intense summer melting enhanced either basal lubrication or shear softening, or both, causing the glacier to thin dynamically. The newly routed upstream sublglacial water was likely to be both retarded and inefficient, thus providing a causal mechanism for the prolonged ice transport to continue well into the winter months. As the climate continues to produce increasingly warmer spring and summer, amplified seasonal waves of mass transport may become ever more present in years of future observations. Increased frequency of amplified seasonal mass transport may ultimately strengthen the Greenland's dynamic ice mass loss, a component of the balance that will have important ramifications for sea level rise. This animation shows a solitary wave passing through Rink Glacier, Greenland, in 2012, recorded by the motion of a GPS station (circle with arrow). Darker blue colors within the flow indicate mass loss, red colors show mass gain. The star marks the center of the wave. Credit: NASA/JPL-Caltech

  4. Solitary paraganglioma of the hypoglossal nerve: case report.

    LENUS (Irish Health Repository)

    Raza, Kazim

    2011-04-01

    BACKGROUND AND IMPORTANCE: We report the case history of solitary hypoglossal paraganglioma in a 64-year-old woman. The surgical difficulties encountered in the removal of this challenging tumor are discussed and as a literature review provided. CLINICAL PRESENTATION: A 64-year-old woman presented with a short history of dysphonia, occasional dysphagia, tinnitus, altered taste, and unilateral left-sided tongue wasting. On examination, there was left lower motor hypoglossal paralysis. Imaging showed a discrete enhancing lobulated mass, measuring 2 × 2 cm, in the region of the hypoglossal nerve extending into the hypoglossal canal suggestive of hypoglossal paraganglioma. A left dorsolateral suboccipital craniotomy was performed with the patient in the sitting position. The hypoglossal nerve appeared to be enlarged, and the jugular foramen was normal. Complete surgical debulking of the tumor was not attempted because of its vascular nature. The nerve was decompressed, and neuropathology confirmed a low-grade paraganglioma arising from the hypoglossal nerve. The patient was scheduled to receive stereotactic radiation for further management. CONCLUSION: When a case of solitary hypoglossal paraganglioma is encountered in clinical practice, the aim of management should be mainly focused on achieving a diagnosis and preserving the hypoglossal nerve function. If there is evidence of vascularity in the lesion noted on magnetic resonance imaging, a preoperative angiogram should be obtained with a view for embolization. We decompressed the hypoglossal canal and achieved good improvement in the patient\\'s symptoms. We recommend stereotactic radiosurgery for remnant and small hypoglossal tumors and regular follow-up with magnetic resonance imaging scans.

  5. Solitary paraganglioma of the hypoglossal nerve: case report.

    LENUS (Irish Health Repository)

    Raza, Kazim

    2012-02-01

    BACKGROUND AND IMPORTANCE: We report the case history of solitary hypoglossal paraganglioma in a 64-year-old woman. The surgical difficulties encountered in the removal of this challenging tumor are discussed and as a literature review provided. CLINICAL PRESENTATION: A 64-year-old woman presented with a short history of dysphonia, occasional dysphagia, tinnitus, altered taste, and unilateral left-sided tongue wasting. On examination, there was left lower motor hypoglossal paralysis. Imaging showed a discrete enhancing lobulated mass, measuring 2 x 2 cm, in the region of the hypoglossal nerve extending into the hypoglossal canal suggestive of hypoglossal paraganglioma. A left dorsolateral suboccipital craniotomy was performed with the patient in the sitting position. The hypoglossal nerve appeared to be enlarged, and the jugular foramen was normal. Complete surgical debulking of the tumor was not attempted because of its vascular nature. The nerve was decompressed, and neuropathology confirmed a low-grade paraganglioma arising from the hypoglossal nerve. The patient was scheduled to receive stereotactic radiation for further management. CONCLUSION: When a case of solitary hypoglossal paraganglioma is encountered in clinical practice, the aim of management should be mainly focused on achieving a diagnosis and preserving the hypoglossal nerve function. If there is evidence of vascularity in the lesion noted on magnetic resonance imaging, a preoperative angiogram should be obtained with a view for embolization. We decompressed the hypoglossal canal and achieved good improvement in the patient\\'s symptoms. We recommend stereotactic radiosurgery for remnant and small hypoglossal tumors and regular follow-up with magnetic resonance imaging scans.

  6. VATS intraoperative tattooing to facilitate solitary pulmonary nodule resection

    Directory of Open Access Journals (Sweden)

    Boutros Cherif

    2008-03-01

    Full Text Available Abstract Introduction Video-assisted thoracic surgery (VATS has become routine and widely accepted for the removal of solitary pulmonary nodules of unknown etiology. Thoracosopic techniques continue to evolve with better instruments, robotic applications, and increased patient acceptance and awareness. Several techniques have been described to localize peripheral pulmonary nodules, including pre-operative CT-guided tattooing with methylene blue, CT scan guided spiral/hook wire placement, and transthoracic ultrasound. As pulmonary surgeons well know, the lung and visceral pleura may appear featureless on top of a pulmonary nodule. Case description This paper presents a rapid, direct and inexpensive approach to peripheral lung lesion resection by marking the lung parenchyma on top of the nodule using direct methylene blue injection. Methods In two patients with peripherally located lung nodules (n = 3 scheduled for VATS, we used direct methylene blue injection for intraoperative localization of the pulmonary nodule. Our technique was the following: After finger palpation of the lung, a spinal 25 gauge needle was inserted through an existing port and 0.1 ml of methylene blue was used to tattoo the pleura perpendicular to the localized nodule. The methylene blue tattoo immediately marks the lung surface over the nodule. The surgeon avoids repeated finger palpation, while lining up stapler, graspers and camera, because of the visible tattoo. Our technique eliminates regrasping and repalpating the lung once again to identify a non marked lesion. Results Three lung nodules were resected in two patients. Once each lesion was palpated it was marked, and the area was resected with security of accurate localization. All lung nodules were resected in totality with normal lung parenchymal margins. Our technique added about one minute to the operative time. The two patients were discharged home on the second postoperative day, with no morbidity. Conclusion

  7. Chaos synchronization of coupled hyperchaotic system

    International Nuclear Information System (INIS)

    Yang Lixin; Chu Yandong; Zhang Jiangang; Li Xianfeng

    2009-01-01

    Chaos synchronization, as an important topic, has become an active research subject in nonlinear science. Over the past two decades, chaos synchronization between nonlinear systems has been extensively studied, and many types of synchronization have been announced. This paper introduces synchronization of coupled hyperchaotic system, based on the Lapunov stability theory, asymptotic stability of the system is guaranteed by means of Lapunov function. The numerical simulation was provided in order to show the effectiveness of this method for the synchronization of the chaotic hyperchaotic Chen system and Rossler system.

  8. Targeting engineering synchronization in chaotic systems

    Science.gov (United States)

    Bhowmick, Sourav K.; Ghosh, Dibakar

    2016-07-01

    A method of targeting engineering synchronization states in two identical and mismatch chaotic systems is explained in detail. The method is proposed using linear feedback controller coupling for engineering synchronization such as mixed synchronization, linear and nonlinear generalized synchronization and targeting fixed point. The general form of coupling design to target any desire synchronization state under unidirectional coupling with the help of Lyapunov function stability theory is derived analytically. A scaling factor is introduced in the coupling definition to smooth control without any loss of synchrony. Numerical results are done on two mismatch Lorenz systems and two identical Sprott oscillators.

  9. Modified function projective synchronization of chaotic system

    International Nuclear Information System (INIS)

    Du Hongyue; Zeng Qingshuang; Wang Changhong

    2009-01-01

    This paper presents a new type synchronization called modified function projective synchronization, where the drive and response systems could be synchronized up to a desired scale function matrix. It is obvious that the unpredictability of the scaling functions can additionally enhance the security of communication. By active control scheme, we take Lorenz system as an example to illustrate above synchronization phenomenon. Furthermore, based on modified function projective synchronization, a scheme for secure communication is investigated in theory. The corresponding numerical simulations are performed to verify and illustrate the analytical results.

  10. A Plaque-Type Solitary Reticulohistiocytoma in a Two-Year-Old Boy

    Science.gov (United States)

    Shibuya, Rintaro; Tanizaki, Hideaki; Kaku, Yo; Yonezawa, Masao; Ryu, Yuri; Otsuka, Atsushi; Kabashima, Kenji; Miyachi, Yoshiki

    2015-01-01

    Reticulohistiocytoma (RH) is a dermal histiocytic infiltration composed of large histiocytes with eosinophilic glassy cytoplasm. RH is classified into three clinical forms: solitary RH, diffuse cutaneous RH without systemic involvement and multicentric reticulohistiocytosis with systemic diseases. Solitary RH generally manifests as a nodular lesion in adults without accompanying systemic diseases. Herein, we describe a case of solitary RH with an atypical clinical manifestation as a red-brown-colored plaque in a 2-year-old boy. Atypical presentations of RH may pose diagnostic difficulty unless RH is considered. A correct diagnosis of RH can ensure avoidance of unnecessary invasive procedures. PMID:25759651

  11. A Plaque-Type Solitary Reticulohistiocytoma in a Two-Year-Old Boy

    Directory of Open Access Journals (Sweden)

    Rintaro Shibuya

    2015-01-01

    Full Text Available Reticulohistiocytoma (RH is a dermal histiocytic infiltration composed of large histiocytes with eosinophilic glassy cytoplasm. RH is classified into three clinical forms: solitary RH, diffuse cutaneous RH without systemic involvement and multicentric reticulohistiocytosis with systemic diseases. Solitary RH generally manifests as a nodular lesion in adults without accompanying systemic diseases. Herein, we describe a case of solitary RH with an atypical clinical manifestation as a red-brown-colored plaque in a 2-year-old boy. Atypical presentations of RH may pose diagnostic difficulty unless RH is considered. A correct diagnosis of RH can ensure avoidance of unnecessary invasive procedures.

  12. Solitary Intra-Osseous Myofibroma of the Jaw: A Case Report and Review of Literature.

    Science.gov (United States)

    Dhupar, Anita; Carvalho, Karla; Sawant, Poonam; Spadigam, Anita; Syed, Shaheen

    2017-10-24

    Myofibroma is a rare benign spindle cell neoplasm in children that usually affects both soft tissue and bone in the head and neck region. Approximately one third of these cases are seen within jaw bones as solitary lesions. Solitary intra-osseous myofibroma of the jaw bone shares its clinical, radiographic and histological features with other spindle cell tumors. The rarity of this lesion can make diagnosis difficult for clinicians and pathologists. We report a case of a solitary intra-osseous myofibroma in the mandible of a nine-year-old child.

  13. Solitary submucous neurofibroma of the mandible: review of the literature and report of a rare case

    Directory of Open Access Journals (Sweden)

    Kübler Norbert R

    2009-11-01

    Full Text Available Abstract Solitary neurofibroma is a rare benign non-odontogenic tumor. Particularly in the oral cavity, neurogenic tumors are rare, especially if they are malignant. Neurofibromas may present either as solitary lesions or as part of the generalised syndrome of neurofibromatosis or von Recklinghausen's disease of the skin. Clinically, oral neurofibromas usually appear as pediculated or sessile nodules, with slow growth and mostly without pain. The diagnosis can be confirmed by histological examination. Neurofibromas are immunopositive for the S-100 protein, indicating its neural origin. Treatment is surgical and the prognosis is excellent. For illustration a rare case of a solitary neurofibroma in the mandible is presented.

  14. Malignant conversion of a solitary papilloma in the distal trachea: report of a case.

    Science.gov (United States)

    Lioulias, Achilleas; Misthos, Panagiotis; Papagiannakis, Georgios; Mermigkis, Dimitrios; Karagianidis, Napoleon; Neofotistos, Kostas; Kokotsakis, John

    2008-10-01

    A solitary papilloma versus the usual multiple lesions of papillomatosis is extremely rare. Even more infrequent is a solitary papilloma of the trachea in an adult patient. In the present report, a case of a solitary papilloma in the distal trachea is presented. After two unsuccessful sessions of laser ablation, resection of the lower one-third of the trachea was performed through a right posterolateral thoracotomy. Postoperative histology results disclosed a malignant degeneration into squamous cell carcinoma. The patient had an excellent outcome after resection of the affected portion of the trachea. There was no evidence of recurrence after 20 months of follow-up.

  15. Malignant Conversion of a Solitary Papilloma in the Distal Trachea: Report of a Case

    Directory of Open Access Journals (Sweden)

    Achilleas Lioulias

    2008-01-01

    Full Text Available A solitary papilloma versus the usual multiple lesions of papillomatosis is extremely rare. Even more infrequent is a solitary papilloma of the trachea in an adult patient. In the present report, a case of a solitary papilloma in the distal trachea is presented. After two unsuccessful sessions of laser ablation, resection of the lower one-third of the trachea was performed through a right posterolateral thoracotomy. Postoperative histology results disclosed a malignant degeneration into squamous cell carcinoma. The patient had an excellent outcome after resection of the affected portion of the trachea. There was no evidence of recurrence after 20 months of follow-up.

  16. Solitary wave solutions as a signature of the instability in the discrete nonlinear Schroedinger equation

    Energy Technology Data Exchange (ETDEWEB)

    Arevalo, Edward, E-mail: arevalo@temf.tu-darmstadt.d [Technische Universitaet Darmstadt, Institut fuer Theorie elektromagnetischer Felder, TEMF, Schlossgartenstr. 8, D-64289 Darmstadt (Germany)

    2009-09-21

    The effect of instability on the propagation of solitary waves along one-dimensional discrete nonlinear Schroedinger equation with cubic nonlinearity is revisited. A self-contained quasicontinuum approximation is developed to derive closed-form expressions for small-amplitude solitary waves. The notion that the existence of nonlinear solitary waves in discrete systems is a signature of the modulation instability is used. With the help of this notion we conjecture that instability effects on moving solitons can be qualitative estimated from the analytical solutions. Results from numerical simulations are presented to support this conjecture.

  17. Case report 437: Solitary (unicameral, simple) bone cyst of the scapula

    Energy Technology Data Exchange (ETDEWEB)

    Ruggieri, P.; Biagnini, M.; Picci, P.

    1987-08-01

    A case has been presented of an expanding, aggressive bone cyst in the scapula of an 11-year-old girl. The lesion had the appearance of a highly aggressive, cyst-like disorder that appeared to be benign. Biopsy and histological preparation confirmed the presence of a solitary bone cyst. The clinical, radiological, and pathological criteria associated with a solitary bone cyst, particularly in the scapula, were discussed and the literature was reviewed. The differential diagnosis was stressed and a number of examples of scapular lesions was presented radiologically, particularly lesions that might be confused with solitary bone cyst. (orig./SHA).

  18. Synchronization to auditory and visual rhythms in hearing and deaf individuals

    Science.gov (United States)

    Iversen, John R.; Patel, Aniruddh D.; Nicodemus, Brenda; Emmorey, Karen

    2014-01-01

    A striking asymmetry in human sensorimotor processing is that humans synchronize movements to rhythmic sound with far greater precision than to temporally equivalent visual stimuli (e.g., to an auditory vs. a flashing visual metronome). Traditionally, this finding is thought to reflect a fundamental difference in auditory vs. visual processing, i.e., superior temporal processing by the auditory system and/or privileged coupling between the auditory and motor systems. It is unclear whether this asymmetry is an inevitable consequence of brain organization or whether it can be modified (or even eliminated) by stimulus characteristics or by experience. With respect to stimulus characteristics, we found that a moving, colliding visual stimulus (a silent image of a bouncing ball with a distinct collision point on the floor) was able to drive synchronization nearly as accurately as sound in hearing participants. To study the role of experience, we compared synchronization to flashing metronomes in hearing and profoundly deaf individuals. Deaf individuals performed better than hearing individuals when synchronizing with visual flashes, suggesting that cross-modal plasticity enhances the ability to synchronize with temporally discrete visual stimuli. Furthermore, when deaf (but not hearing) individuals synchronized with the bouncing ball, their tapping patterns suggest that visual timing may access higher-order beat perception mechanisms for deaf individuals. These results indicate that the auditory advantage in rhythmic synchronization is more experience- and stimulus-dependent than has been previously reported. PMID:25460395

  19. Efficient localization of synchronous EEG source activities using a modified RAP-MUSIC algorithm.

    Science.gov (United States)

    Liu, Hesheng; Schimpf, Paul H

    2006-04-01

    Synchronization across different brain regions is suggested to be a possible mechanism for functional integration. Noninvasive analysis of the synchronization among cortical areas is possible if the electrical sources can be estimated by solving the electroencephalography inverse problem. Among various inverse algorithms, spatio-temporal dipole fitting methods such as RAP-MUSIC and R-MUSIC have demonstrated superior ability in the localization of a restricted number of independent sources, and also have the ability to reliably reproduce temporal waveforms. However, these algorithms experience difficulty in reconstructing multiple correlated sources. Accurate reconstruction of correlated brain activities is critical in synchronization analysis. In this study, we modified the well-known inverse algorithm RAP-MUSIC to a multistage process which analyzes the correlation of candidate sources and searches for independent topographies (ITs) among precorrelated groups. Comparative studies were carried out on both simulated data and clinical seizure data. The results demonstrated superior performance with the modified algorithm compared to the original RAP-MUSIC in recovering synchronous sources and localizing the epileptiform activity. The modified RAP-MUSIC algorithm, thus, has potential in neurological applications involving significant synchronous brain activities.

  20. Anticipated and zero-lag synchronization in motifs of delay-coupled systems.

    Science.gov (United States)

    Mirasso, Claudio R; Carelli, Pedro V; Pereira, Tiago; Matias, Fernanda S; Copelli, Mauro

    2017-11-01

    Anticipated and zero-lag synchronization have been observed in different scientific fields. In the brain, they might play a fundamental role in information processing, temporal coding and spatial attention. Recent numerical work on anticipated and zero-lag synchronization studied the role of delays. However, an analytical understanding of the conditions for these phenomena remains elusive. In this paper, we study both phenomena in systems with small delays. By performing a phase reduction and studying phase locked solutions, we uncover the functional relation between the delay, excitation and inhibition for the onset of anticipated synchronization in a sender-receiver-interneuron motif. In the case of zero-lag synchronization in a chain motif, we determine the stability conditions. These analytical solutions provide an excellent prediction of the phase-locked regimes of Hodgkin-Huxley models and Roessler oscillators.

  1. Anticipated and zero-lag synchronization in motifs of delay-coupled systems

    Science.gov (United States)

    Mirasso, Claudio R.; Carelli, Pedro V.; Pereira, Tiago; Matias, Fernanda S.; Copelli, Mauro

    2017-11-01

    Anticipated and zero-lag synchronization have been observed in different scientific fields. In the brain, they might play a fundamental role in information processing, temporal coding and spatial attention. Recent numerical work on anticipated and zero-lag synchronization studied the role of delays. However, an analytical understanding of the conditions for these phenomena remains elusive. In this paper, we study both phenomena in systems with small delays. By performing a phase reduction and studying phase locked solutions, we uncover the functional relation between the delay, excitation and inhibition for the onset of anticipated synchronization in a sender-receiver-interneuron motif. In the case of zero-lag synchronization in a chain motif, we determine the stability conditions. These analytical solutions provide an excellent prediction of the phase-locked regimes of Hodgkin-Huxley models and Roessler oscillators.

  2. Synchronous replication of remote storage

    OpenAIRE

    Mirzoev, Dr. Timur

    2014-01-01

    Storage replication is one of the essential requirements for network environments. While many forms of Network Attached Storage (NAS), Storage Area Networks (SAN) and other forms of network storage exist, there is a need for a reliable synchronous storage replication technique between distant sites (less than 1 mile). Such technology allows setting new standards for network failover and failback systems for virtual servers; specifically, addressing the growing need for effective disaster reco...

  3. Synchronization matters for motor coordination.

    Science.gov (United States)

    Pesce Ibarra, Luigi S

    2018-03-01

    Using electroencephalography and electromyography recordings from healthy participants during a visual-depended bimanual coordination task, de Vries and colleagues showed that functional synchronization is important in motor coordination. The authors reported that higher coordination correlated positively with intermuscular synchrony, but correlated negatively with corticomuscular synchrony. They proposed that these two diverse motor systems operate differently depending on task demands. Similar experimental paradigms could identify motor mechanisms in patients with neurological disorders to design novel rehabilitation strategies.

  4. Radiosurgery for brain metastases: is whole brain radiation therapy necessary?

    International Nuclear Information System (INIS)

    Forstner, Julie M.; Sneed, Penny K.; Lamborn, Kathleen R.; Shu, H.-K.G.; McDermott, Michael W.; Park, Elaine; Ho, Maria; Chang, Susan; Gutin, Philip H.; Phillips, Theodore L.; Wara, William M.; Larson, David A.

    1996-01-01

    Purpose: Because whole brain radiotherapy (WBRT) carries a significant risk of dementia in long-term survivors, it is desirable to determine if some patients with brain metastases may be managed with radiosurgery (RS) alone, reserving WBRT for salvage therapy as needed. To begin to approach this problem, we retrospectively reviewed freedom from brain failure/progression (Brain FFP) and survival of patients with newly-diagnosed solitary or multiple brain metastases treated with Gamma Knife RS ± WBRT. Materials and Methods: All patients treated at our institution with Gamma Knife RS for newly-diagnosed solitary or multiple (2-8) brain metastases from September 1991 through December 1995 were reviewed. Whether or not WBRT was given depended on physician preference and referral patterns. Brain FFP was measured from the date of RS until development of a new brain metastasis or progression of a treated metastasis, with censoring at the time of the last imaging study. Survival was measured from the date of RS until death or last clinical follow-up. Actuarial curves were estimated using the Kaplan-Meier method and compared with the log rank test. Multivariate analyses to adjust for known prognostic variables (age, KPS, history of extracranial metastases, and total target volume) were performed using the Cox proportional hazards model. Results: From September 1991-December 1995, 90 patients with newly-diagnosed brain metastases underwent RS. Three patients treated palliatively to a small component of their intracranial disease were excluded, leaving 54 treated with RS alone and 33 treated with RS + WBRT. Age ranged from 31-83 years (median, 59 years), KPS from 60-100 (median, 90), and total target volume from 0.15-26.1 cm 3 (median, 5.5 cm 3 ). Fifty patients had a history of extracranial metastases. Results are shown below. In the RS alone group, (22(54)) patients (41%) had a brain failure and (20(54)) (37%) died without evidence of brain failure. In the RS + WBRT group

  5. Dynamics of Solitary Wave Pulses Near the Zero-Dispersion Wavelength in Optical Fibers

    National Research Council Canada - National Science Library

    Akylas, Triantaphyllos

    1998-01-01

    .... Near the zero-dispersion wavelength (ZDW), the borderline between normal and anomalous dispersion, however, dispersive effects are relatively weak and it would seem most efficient to operate there, assuming that one can launch solitary wave...

  6. Spectrum of congenital mitral valve abnormalities associated with solitary undifferentiated papillary muscle in adults

    Directory of Open Access Journals (Sweden)

    Jagdish C. Mohan

    2016-09-01

    Conclusion: In adult patients, a high index of suspicion is required to detect congenital mitral stenosis/regurgitation with large solitary PM (resembling a parachute mitral valve which may masquerade as hypertrophic cardiomyopathy or rheumatic mitral valve disease.

  7. The phylogenetic position of the solitary zoanthid genus Sphenopus (Cnidaria: Hexacorallia)

    NARCIS (Netherlands)

    Reimer, J.D.; Lin, M.; Fujii, T.

    2012-01-01

    The zoanthid genus Sphenopus (Cnidaria: Anthozoa: Zoantharia), like many other brachycnemic zoanthids, is found in shallow subtropical and tropical waters, but is uniquely unitary (solitary, monostomatous), azooxanthellate, and free-living. With sparse knowledge of its phylogenetic position, this

  8. Factors influencing malignant evolution and long-term survival in solitary fibrous tumours of the pleura

    OpenAIRE

    Rodríguez-González, Marta; Novoa, Nuria M.; Gomez, Maria T.; García, Juan L.; Ludeña, María Dolores

    2014-01-01

    Solitary pleuro-pulmonary fibrous tumours are relatively uncommon neoplasms that are difficult to manage therapeutically and which, cytogenetically, have been poorly studied. The aim of the present work was to analyse the characteristics of a series of consecutive operated solitary pleural fibrous tumours in an attempt to discover a malignant pattern of evolution. This was a retrospective observational study of 19 cases. Samples were studied for clinical, histological, immunohistochemical and...

  9. Construction of solitary solution and compacton-like solution by variational iteration method

    International Nuclear Information System (INIS)

    He Jihuan; Wu Xuhong

    2006-01-01

    Variational iteration method is used to construct solitary solutions and compacton-like solutions for nonlinear dispersive equations. The chosen initial solution (trial function) can be in compacton form or in soliton form with some unknown parameters which can be determined in the solution procedure. The compacton-like solution can be converted to solitary solution by suitable choice of a parameter, and vice versa

  10. Solitary cystic lymph neck node metastasis of occult thyroid papillary carcinoma

    OpenAIRE

    González García, R.; Román Romero, Leticia; Sastre Pérez, Jesús; Rodríguez Campo, Francisco José; Naval Gias, Luis

    2008-01-01

    The appearance of a solitary lateral cervical cystic mass as the only initial presenting symptom of occult thyroid carcinoma is uncommon. Its presence is often misdiagnosed due to the more frequent branchial cyst in young people. Although oronasopharyngeal squamous cell carcinoma has been reported as the main cause of lymph neck node metastasis, thyroid papillary carcinoma may be responsible for solitary cervical cystic masses as the initial manifestation of the disease. This situation ha...

  11. Polarized seismic and solitary waves run-up at the sea bed

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, L. C.C.; Zainal, A. A.; Faisal, S. Y. [Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia); Universiti Teknologi Malaysia, 81310 Johor Bahru (Malaysia)

    2012-09-26

    The polarization effects in hydrodynamics are studied. Hydrodynamic equation for the nonlinear wave is used along with the polarized solitary waves and seismic waves act as initial waves. The model is then solved by Fourier spectral and Runge-Kutta 4 methods, and the surface plot is drawn. The output demonstrates the inundation behaviors. Consequently, the polarized seismic waves along with the polarized solitary waves tend to generate dissimilar inundation which is more disastrous.

  12. Borrelia burgdorferi sensu lato bacteremia in Slovenian children with solitary and multiple erythema migrans.

    Science.gov (United States)

    Arnež, Maja; Ružić-Sabljić, Eva

    2011-11-01

    To establish the frequency and characteristics of Borrelia burgdorferi sensu lato bacteremia in Slovenian children with solitary and multiple erythema migrans, 1164 patients were included in this prospective study. Bacteremia was established in 11.4% of all patients, 15.8% of patients with multiple erythema migrans, and in 7.6% of patients with solitary erythema migrans. Bacteremia can be detected in children, with untreated erythema migrans, up to 39 days after the onset of skin rash.

  13. Space-charge solitary waves and double layers in n-type compensated semiconductor quantum plasma

    Science.gov (United States)

    Banerjee, S.; Ghosh, B.

    2018-03-01

    Using quantum hydrodynamic (QHD) model and standard reductive perturbation method, we have investigated the formation and characteristics of space-charge solitary waves and double layers in n-type compensated drifting semiconductor plasma with varying doping profiles. Through numerical analysis, it is shown that the structures of space-charge solitary waves and double layers depend significantly on electron drift and compensation parameter which measures a comparative proportion of the donor, acceptor and intrinsic ion concentrations.

  14. Solitary splenic metastasis from nasopharyngeal carcinoma: a case report and systematic review of the literature

    OpenAIRE

    Genova, Pietro; Brunetti, Francesco; Bequignon, Emilie; Landi, Filippo; Lizzi, Vincenzo; Esposito, Francesco; Charpy, Cecile; Calderaro, Julien; Azoulay, Daniel; de?Angelis, Nicola

    2016-01-01

    Background Solitary splenic metastases are a rare occurrence, and the nasopharyngeal carcinoma represents one of the most uncommon primary sources. The present study aimed to describe a rare case of a solitary single splenic metastasis from nasopharyngeal carcinoma and to assess the number of cases of isolated nasopharyngeal carcinoma metastases to the spleen reported in the literature. Main body We describe the case of a 56-year-old man with a history of nasopharyngeal carcinoma and complete...

  15. Magnetic resonance imaging findings of solitary infantile myofibromatosis of the skull: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Eun; Cho, Kil Ho; Suh, Jang Ho; Choi, Joon Hyuk [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    2016-11-15

    Infantile myofibromatosis is a rare, benign mesenchymal disorder of early childhood characterized by solitary or multiple benign myofibroblastic tumors. The tumors may involve the skin, subcutaneous tissue, muscle, bone and visceral organs. We report magnetic resonance imaging findings of solitary infantile myofibromatosis arising in the temporal bone of a ten-month-old boy, and the diagnosis was confirmed by surgical excision and histopathological examination.

  16. A rare cause of severe rectal bleeding: solitary rectal ulcer syndrome.

    Science.gov (United States)

    Urganc, Nafiye; Kalyoncu, Derya; Usta, Merve; Eken, Kamile Gulcin

    2014-10-01

    Solitary rectal ulcer syndrome is a rare benign disorder in children which often goes unrecognized or easily misdiagnosed with other common diseases. It usually presents with rectal bleeding, constipation, mucous discharge, prolonged straining, tenesmus, and lower abdominal pain. The rectal bleeding varies from a little fresh blood to severe hemorrhage that requires blood transfusion. We report herein a pediatric case of solitary rectal ulcer syndrome who admitted to pediatric emergency department with severe rectal bleeding for reminding this rare syndrome.

  17. Stereotactic radiosurgery for brain metastases

    International Nuclear Information System (INIS)

    Obedian, E.; Lotbiniere, A.C.J. de; Haffty, B.G.; Piepmeier, J.M.; Fischer, D.B.; Knisely, J.P.S.

    1997-01-01

    Purpose: This study evaluates the influence of several prognostic factors on overall survival and progression free survival in patients undergoing stereotactic radiosurgery (SRS) for brain metastases. Materials and Methods: Records of 61 coecutive patients with pathologically confirmed extra-cranial malignancies undergoing SRS at Yale University School of Medicine between 12/18/91 and 7/2/96 were reviewed. All patients underwent head frame localization and CT and/or MRI based treatment planning. Outcome was analyzed with respect to age, number of lesions, size of lesions, location of lesions, site and stage of primary tumor, status of primary tumor at time of SRS, history of whole brain radiation therapy (WBRT), surgery, and/or chemotherapy prior to or after SRS, delay in SRS from diagnosis of brain metastases, dose of radiation delivered, and brain metastasis free interval. Both overall survival and progression free survival were analyzed by the Kaplan-Meier method. Tests for statistical significance were performed using the Cox proportional hazards model. Results: Median follow-up was 29 months. 3% ((8(61))) of patients displayed evidence of progressive disease at the site of SRS, and 87% ((53(61))) of patients have died. Overall and progression free survival rates for the entire cohort of patients were 43.8% and 89.5% at 1 year and 11.1% and 71.4% at 2 years, respectively. Patients undergoing SRS for a solitary brain metastasis had a significant improvement in overall survival with 1 year survival rates of 52.6% vs. 32.7% for patients undergoing SRS for more than 1 brain metastasis (p=0.002). Patients who presented with progressive systemic disease at the time of SRS had an inferior overall survival with a 1 year survival rate of 15.4% compared to patients with presumed/known stable disease who had a 1 year survival rate of 51.5%/54.2% (p<0.001). Patients treated for cerebral metastases had a higher progression free survival compared to patients undergoing SRS

  18. Synchronous meningioma and anaplastic large cell lymphoma.

    Science.gov (United States)

    Colen, Chaim B; Rayes, Mahmoud; Kupsky, William J; Guthikonda, Murali

    2010-06-01

    Synchronous primary brain tumors are exceedingly rare. When they occur, most cases are associated with metastatic disease. To the best of our knowledge, we report the first case of an atypical meningioma infiltrated by a T-cell-primary central nervous system lymphoma (PCNSL), specifically anaplastic large cell lymphoma (ALCL). We present a novel, unifying, plausible mechanism for its origin based on theories in the current literature. A 65-year-old man with a history of near-total resection of atypical meningioma presented with a complaint of progressive headaches. Imaging revealed recurrent tumor. Left frontal-temporal craniotomy with near-total tumor resection followed by radiation was performed. Recurrent symptomatic tumor led to repeat left frontotemporal craniotomy with tumor resection and partial anterior temporal lobectomy. Part of the specimen showed predominantly fibrotic neoplasm composed of nests and whorls of meningothelial cells, highlighted by epithelial membrane antigen (EMA) staining. The remainder of the specimen consisted of densely cellular neoplasm centered in connective tissue, including areas involved by meningioma. This tumor was composed of moderately large lymphoid cells with large nuclei, prominent nucleoli, and amphophilic cytoplasm. These cells were strongly immunoreactive for CD3 and CD30 but remained unstained with EMA, anaplastic lymphoma kinase-1 (ALK-1), CD15 or cytotoxic associated antigen TIA-1. Smaller mature lymphocytes, chiefly T-cells, were intermixed. The morphologic and immunohistochemical features were considered typical of anaplastic large T-cell lymphoma. The pathogenesis of this association may have been due to radiation-mediated breakdown of the blood-brain barrier with subsequent T-cell infiltration and proliferation. We advocate aggressive resection and long-term surveillance for individuals with metastasis, especially higher-grade neoplasms that receive radiotherapy.

  19. Solitary cannabis use frequency mediates the relationship between social anxiety and cannabis use and related problems.

    Science.gov (United States)

    Buckner, Julia D; Ecker, Anthony H; Dean, Kimberlye E

    2016-03-01

    Individuals with elevated social anxiety are seven times more likely to meet criteria for cannabis use disorders, yet social anxiety is unrelated to more frequent cannabis use. The lack of relation to cannabis use frequency may be at least partially due to lack of attention to cannabis use context. It may be that socially anxious persons engage in frequent solitary cannabis use, perhaps using before social situations in the hope that being intoxicated during the social event will help them feel less anxious. In fact, using cannabis alone has been associated with experiencing more cannabis-related problems in prior work. The current study sought to identify whether solitary cannabis use frequency mediated the relationship between social anxiety and cannabis-related problems among 276 current cannabis using undergraduates who completed an online survey of putative predictors of substance use. Social anxiety was robustly related to more frequent solitary (but not social) cannabis use and solitary cannabis use frequency uniquely mediated the relation of social anxiety to cannabis use and related problems. Frequent solitary use appears to play an important role in the experience of cannabis-related problems among socially anxious persons. Intervention strategies may benefit from targeting frequent solitary cannabis use, particularly among at-risk users such as those with elevated social anxiety. © American Academy of Addiction Psychiatry.

  20. Dust ion acoustic solitary structures in the presence of isothermal positrons

    Energy Technology Data Exchange (ETDEWEB)

    Paul, A. [Jadavpur University, Department of Mathematics (India); Das, A. [B. N. S. U. P. School (India); Bandyopadhyay, A., E-mail: abandyopadhyay1965@gmail.com [Jadavpur University, Department of Mathematics (India)

    2017-02-15

    The Sagdeev potential technique has been employed to study the dust ion acoustic solitary waves and double layers in an unmagnetized collisionless dusty plasma consisting of negatively charged static dust grains, adiabatic warm ions, isothermally distributed electrons, and positrons. A computational scheme has been developed to draw the qualitatively different compositional parameter spaces or existence domains showing the nature of existence of different solitary structures with respect to any parameter of the present plasma system. The present system supports both positive and negative potential double layers. The negative potential double layer always restricts the occurrence of negative potential solitary waves, i.e., any sequence of negative potential solitary waves having monotonically increasing amplitude converges to a negative potential double layer. However, there exists a parameter regime for which the positive potential double layer is unable to restrict the occurrence of positive potential solitary waves. As a result, in this region of the parameter space, there exist solitary waves after the formation of positive potential double layer, i.e., positive potential supersolitons have been observed.

  1. Solitary Cannabis Use Frequency Mediates the Relationship Between Social Anxiety and Cannabis Use and Related Problems

    Science.gov (United States)

    Buckner, Julia D.; Ecker, Anthony H.; Dean, Kimberlye E.

    2016-01-01

    Background and Objectives Individuals with elevated social anxiety are seven times more likely to meet criteria for cannabis use disorders, yet social anxiety is unrelated to more frequent cannabis use. The lack of relation to cannabis use frequency may be at least partially due to lack of attention to cannabis use context. It may be that socially anxious persons engage in frequent solitary cannabis use, perhaps using before social situations in the hope that being intoxicated during the social event will help them feel less anxious. In fact, using cannabis alone has been associated with experiencing more cannabis-related problems in prior work. Methods The current study sought to identify whether solitary cannabis use frequency mediated the relationship between social anxiety and cannabis-related problems among 276 current cannabis using undergraduates who completed an online survey of putative predictors of substance use. Results Social anxiety was robustly related to more frequent solitary (but not social) cannabis use and solitary cannabis use frequency uniquely mediated the relation of social anxiety to cannabis use and related problems. Discussion and Conclusions Frequent solitary use appears to play an important role in the experience of cannabis-related problems among socially anxious persons. Scientific Significance Intervention strategies may benefit from targeting frequent solitary cannabis use, particularly among at-risk users such as those with elevated social anxiety. PMID:26890064

  2. Large amplitude ion-acoustic solitary waves and double layers in multicomponent plasma with positrons

    International Nuclear Information System (INIS)

    Sabry, R.

    2009-01-01

    A finite amplitude theory for ion-acoustic solitary waves and double layers in multicomponent plasma consisting of hot positrons, cold ions, and electrons with two-electron temperature distributions is presented. Conditions are obtained under which large amplitude stationary ion-acoustic solitary waves and double layers can exist. For the physical parameters of interest, the ion-acoustic solitary wave (double layers) profiles and the relationship between the maximum soliton (double layers) amplitude and the Mach number are found. Also, we have presented the region of existence of the large amplitude ion-acoustic waves by analyzing the structure of the pseudopotential. For the selected range of parameters, it is found that only positive solitary waves and double layers can exist. An analysis for the small amplitude limit through the Sagdeev pseudopotential analysis and the reductive perturbation theory shows the existence of positive and negative ion-acoustic solitary waves and double layers. The effects of positron concentration and temperature ratio on the characteristics of the solitary ion-acoustic waves and double layers (namely, the amplitude and width) are discussed in detail. The relevance of this investigation to space and laboratory plasmas is pointed out.

  3. Large amplitude ion-acoustic solitary waves and double layers in multicomponent plasma with positrons

    Science.gov (United States)

    Sabry, R.

    2009-07-01

    A finite amplitude theory for ion-acoustic solitary waves and double layers in multicomponent plasma consisting of hot positrons, cold ions, and electrons with two-electron temperature distributions is presented. Conditions are obtained under which large amplitude stationary ion-acoustic solitary waves and double layers can exist. For the physical parameters of interest, the ion-acoustic solitary wave (double layers) profiles and the relationship between the maximum soliton (double layers) amplitude and the Mach number are found. Also, we have presented the region of existence of the large amplitude ion-acoustic waves by analyzing the structure of the pseudopotential. For the selected range of parameters, it is found that only positive solitary waves and double layers can exist. An analysis for the small amplitude limit through the Sagdeev pseudopotential analysis and the reductive perturbation theory shows the existence of positive and negative ion-acoustic solitary waves and double layers. The effects of positron concentration and temperature ratio on the characteristics of the solitary ion-acoustic waves and double layers (namely, the amplitude and width) are discussed in detail. The relevance of this investigation to space and laboratory plasmas is pointed out.

  4. Anomalous width variation of rarefactive ion acoustic solitary waves in the context of auroral plasmas

    Directory of Open Access Journals (Sweden)

    S. S. Ghosh

    2004-01-01

    Full Text Available The presence of dynamic, large amplitude solitary waves in the auroral regions of space is well known. Since their velocities are of the order of the ion acoustic speed, they may well be considered as being generated from the nonlinear evolution of ion acoustic waves. However, they do not show the expected width-amplitude correlation for K-dV solitons. Recent POLAR observations have actually revealed that the low altitude rarefactive ion acoustic solitary waves are associated with an increase in the width with increasing amplitude. This indicates that a weakly nonlinear theory is not appropriate to describe the solitary structures in the auroral regions. In the present work, a fully nonlinear analysis based on Sagdeev pseudopotential technique has been adopted for both parallel and oblique propagation of rarefactive solitary waves in a two electron temperature multi-ion plasma. The large amplitude solutions have consistently shown an increase in the width with increasing amplitude. The width-amplitude variation profile of obliquely propagating rarefactive solitary waves in a magnetized plasma have been compared with the recent POLAR observations. The width-amplitude variation pattern is found to fit well with the analytical results. It indicates that a fully nonlinear theory of ion acoustic solitary waves may well explain the observed anomalous width variations of large amplitude structures in the auroral region.

  5. Solitary cannabis use in adolescence as a correlate and predictor of cannabis problems.

    Science.gov (United States)

    Creswell, Kasey G; Chung, Tammy; Clark, Duncan B; Martin, Christopher S

    2015-11-01

    Most adolescent cannabis use occurs in social settings among peers. Solitary cannabis use during adolescence may represent an informative divergence from normative behavior with important implications for understanding risk for cannabis problems. This longitudinal study examined associations of adolescent solitary cannabis use with levels of cannabis use and problems in adolescence and in young adulthood. Cannabis using-adolescents aged 12-18 were recruited from clinical programs (n=354; 43.8% female; 83.3% Caucasian) and community sources (n=93; 52.7% female; 80.6% Caucasian). Participants reported on cannabis use patterns and diagnostic symptoms at baseline and multiple follow-ups into young adulthood. Compared to social-only users, adolescent solitary cannabis users were more likely to be male and reported more frequent cannabis use and more DSM-IV cannabis use disorder (CUD) symptoms. Regression analyses showed that solitary cannabis use in adolescence predicted CUD symptom counts in young adulthood (age 25) after controlling for demographic variables and the frequency of adolescent cannabis use. However, solitary adolescent cannabis use was no longer predictive of age 25 CUD symptoms after additionally controlling for adolescent CUD symptoms. Solitary cannabis use is associated with greater cannabis use and problems during adolescence, but evidence is mixed that it predicts young adult cannabis problems. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. New family of solitary waves in granular dimer chains with no precompression.

    Science.gov (United States)

    Jayaprakash, K R; Starosvetsky, Yuli; Vakakis, Alexander F

    2011-03-01

    In the present paper we report the existence of a new family of solitary waves in general one-dimensional dimer chains with elastic interactions between beads obeying a strongly nonlinear Hertzian force law. These dimers consist of pairs of "heavy" and "light" beads with no precompression. The solitary waves reported herein can be considered as analogous to the solitary waves in general homogeneous granular chains studied by Nesterenko, in the sense that they do not involve separations between beads, but rather satisfy special symmetries or, equivalently antiresonances in their intrinsic dynamics. We conjecture that these solitary waves are the direct products of a countable infinity of antiresonances in the dimer. An interesting finding is that the solitary waves in the dimer propagate faster than solitary waves in the corresponding homogeneous granular chain obtained in the limit of no mass mismatch between beads (i.e., composed of only heavy beads). This finding, which might seem counterintuitive, indicates that under certain conditions nonlinear antiresonances can increase the speed of disturbance transmission in periodic granular media, through the generation of different ways for transferring energy to the far field of these media. From a practical point of view, this result can have interesting implications in applications where granular media are employed as shock transmitters or attenuators.

  7. [Solitary stones of the lower renal calyx: how to treat?

    Science.gov (United States)

    Martov, A G; Ergakov, D V; Andronov, A S; Dutov, S V; Takhaev, R A; Kil'chukov, Z I; Moskalenko, S A

    2017-06-01

    The choice of treatment for the stones of the lower renal calyx is one of the challenging issues of modern urology. The aim of this retrospective and prospective study was to investigate the clinical effectiveness and safety of 3 modern minimally invasive techniques for treating renal stones: percutaneous (PNL) and transurethral (TNL) nephrolithotripsy and extracorporeal shock wave lithotripsy (ESWL) in patients with solitary lower calyx stones sized from 10 to 15 mm. The study included 136 patients with symptomatic stones of the lower calyces, who underwent ESWL, PNL and TNL from November 2010 to the present day. The criteria for inclusion in the study were: the presence of a solitary stone of the lower calyx, the stone size of 10 mm to 15 mm, the performance of the classical (standard) PNL in the prone position (puncture access 28-30 Fr) and the follow-up examination at 3 months after the operation. Forty-six patients underwent ESWL, 49 - PNL, and 41 - TNL. Postoperative follow-up was done at 3 months and included a plain radiography, ultrasound and non-contrast-enhanced computed tomography. The stone free rate (SFR) was used as a criterion for the effectiveness of the intervention, where the stone size of 3 mm was taken as the upper limit for the possible presence of fragments. Besides, the rate of repeat interventions, complications and subjective assessment of patients treatment satisfaction (0 to 10) by using visual analogue scale (VAS) were investigated. The effectiveness analysis of the three methods for treating the lower calyx stones sized 10-15 mm showed that PNL was no more effective than TNL (SFR 95.9% and 85.4%, respectively), but both methods were significantly more effective than ESWL (SFR 69.5%). 29.3% of patients who underwent TNL required repeat interventions (TNL or ESWL), while among those treated with ESWL, 45.6% required repeat ESWL sessions. PNL resulted in stone clearance in one stage. Postoperative inflammatory complications were most

  8. Explosive synchronization coexists with classical synchronization in the Kuramoto model

    Energy Technology Data Exchange (ETDEWEB)

    Danziger, Michael M., E-mail: michael.danziger@biu.ac.il; Havlin, Shlomo [Department of Physics, Bar-Ilan University, Ramat Gan (Israel); Moskalenko, Olga I.; Kurkin, Semen A. [Faculty of Nonlinear Processes, Saratov State University, Astrakhanskaya, 83, Saratov 410012 (Russian Federation); Saratov State Technical University, Politehnicheskaya, 77, Saratov 410054 (Russian Federation); Zhang, Xiyun [Department of Physics, East China Normal University, Shanghai 200062 (China); Boccaletti, Stefano [CNR-Institute of Complex Systems, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Florence (Italy); The Italian Embassy in Israel, 25 Hamered Street, 68125 Tel Aviv (Israel)

    2016-06-15

    Explosive synchronization has recently been reported in a system of adaptively coupled Kuramoto oscillators, without any conditions on the frequency or degree of the nodes. Here, we find that, in fact, the explosive phase coexists with the standard phase of the Kuramoto oscillators. We determine this by extending the mean-field theory of adaptively coupled oscillators with full coupling to the case with partial coupling of a fraction f. This analysis shows that a metastable region exists for all finite values of f > 0, and therefore explosive synchronization is expected for any perturbation of adaptively coupling added to the standard Kuramoto model. We verify this theory with GPU-accelerated simulations on very large networks (N ∼ 10{sup 6}) and find that, in fact, an explosive transition with hysteresis is observed for all finite couplings. By demonstrating that explosive transitions coexist with standard transitions in the limit of f → 0, we show that this behavior is far more likely to occur naturally than was previously believed.

  9. Synchronization in complex networks with switching topology

    International Nuclear Information System (INIS)

    Wang, Lei; Wang, Qing-guo

    2011-01-01

    This Letter investigates synchronization issues of complex dynamical networks with switching topology. By constructing a common Lyapunov function, we show that local and global synchronization for a linearly coupled network with switching topology can be evaluated by the time average of second smallest eigenvalues corresponding to the Laplacians of switching topology. This result is quite powerful and can be further used to explore various switching cases for complex dynamical networks. Numerical simulations illustrate the effectiveness of the obtained results in the end. -- Highlights: → Synchronization of complex networks with switching topology is investigated. → A common Lyapunov function is established for synchronization of switching network. → The common Lyapunov function is not necessary to monotonically decrease with time. → Synchronization is determined by the second smallest eigenvalue of its Laplacian. → Synchronization criterion can be used to investigate various switching cases.

  10. Control for a synchronization-desynchronization switch

    Science.gov (United States)

    He, Zhiwei; Wang, Xingang; Zhang, Guo-Yong; Zhan, Meng

    2014-07-01

    How to freely enhance or suppress synchronization of networked dynamical systems is of great importance in many disciplines. A unified precise control method for a synchronization-desynchronization switch, called the pull-push control method, is suggested. Namely, synchronization can be achieved when the original systems are desynchronous by pulling (or protecting) one node or a certain subset of nodes, whereas desynchronization can be accomplished when the systems are already synchronous by pushing (or kicking) one node or a certain subset of nodes. With this method, the controlled nodes should be chosen by the generalized eigenvector centrality of the critical synchronization mode of the Laplacian matrix. Compared with existing control methods for synchronization, it displays high efficiency, flexibility, and precision as well.

  11. A chimeric path to neuronal synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Essaki Arumugam, Easwara Moorthy; Spano, Mark L. [School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona 85287-9709 (United States)

    2015-01-15

    Synchronization of neuronal activity is associated with neurological disorders such as epilepsy. This process of neuronal synchronization is not fully understood. To further our understanding, we have experimentally studied the progression of this synchronization from normal neuronal firing to full synchronization. We implemented nine FitzHugh-Nagumo neurons (a simplified Hodgkin-Huxley model) via discrete electronics. For different coupling parameters (synaptic strengths), the neurons in the ring were either unsynchronized or completely synchronized when locally coupled in a ring. When a single long-range connection (nonlocal coupling) was introduced, an intermediate state known as a chimera appeared. The results indicate that (1) epilepsy is likely not only a dynamical disease but also a topological disease, strongly tied to the connectivity of the underlying network of neurons, and (2) the synchronization process in epilepsy may not be an “all or none” phenomenon, but can pass through an intermediate stage (chimera)

  12. A chimeric path to neuronal synchronization

    International Nuclear Information System (INIS)

    Essaki Arumugam, Easwara Moorthy; Spano, Mark L.

    2015-01-01

    Synchronization of neuronal activity is associated with neurological disorders such as epilepsy. This process of neuronal synchronization is not fully understood. To further our understanding, we have experimentally studied the progression of this synchronization from normal neuronal firing to full synchronization. We implemented nine FitzHugh-Nagumo neurons (a simplified Hodgkin-Huxley model) via discrete electronics. For different coupling parameters (synaptic strengths), the neurons in the ring were either unsynchronized or completely synchronized when locally coupled in a ring. When a single long-range connection (nonlocal coupling) was introduced, an intermediate state known as a chimera appeared. The results indicate that (1) epilepsy is likely not only a dynamical disease but also a topological disease, strongly tied to the connectivity of the underlying network of neurons, and (2) the synchronization process in epilepsy may not be an “all or none” phenomenon, but can pass through an intermediate stage (chimera)

  13. Potential Mechanisms and Functions of Intermittent Neural Synchronization

    Directory of Open Access Journals (Sweden)

    Sungwoo Ahn

    2017-05-01

    Full Text Available Neural synchronization is believed to play an important role in different brain functions. Synchrony in cortical and subcortical circuits is frequently variable in time and not perfect. Few long intervals of desynchronized dynamics may be functionally different from many short desynchronized intervals although the average synchrony may be the same. Recent analysis of imperfect synchrony in different neural systems reported one common feature: neural oscillations may go out of synchrony frequently, but primarily for a short time interval. This study explores potential mechanisms and functional advantages of this short desynchronizations dynamics using computational neuroscience techniques. We show that short desynchronizations are exhibited in coupled neurons if their delayed rectifier potassium current has relatively large values of the voltage-dependent activation time-constant. The delayed activation of potassium current is associated with generation of quickly-rising action potential. This “spikiness” is a very general property of neurons. This may explain why very different neural systems exhibit short desynchronization dynamics. We also show how the distribution of desynchronization durations may be independent of the synchronization strength. Finally, we show that short desynchronization dynamics requires weaker synaptic input to reach a pre-set synchrony level. Thus, this dynamics allows for efficient regulation of synchrony and may promote efficient formation of synchronous neural assemblies.

  14. Method for Converter Synchronization with RF Injection

    OpenAIRE

    Joshua P. Bruckmeyer; Ivica Kostanic

    2015-01-01

    This paper presents an injection method for synchronizing analog to digital converters (ADC). This approach can eliminate the need for precision routed discrete synchronization signals of current technologies, such as JESD204. By eliminating the setup and hold time requirements at the conversion (or near conversion) clock rate, higher sample rate systems can be synchronized. Measured data from an existing multiple ADC conversion system was used to evaluate the method. Coherent beams were simu...

  15. Synchronizing a class of uncertain chaotic systems

    International Nuclear Information System (INIS)

    Chen Maoyin; Zhou Donghua; Shang Yun

    2005-01-01

    This Letter deals with the synchronization of a class of uncertain chaotic systems in the drive-response framework. A robust adaptive observer based response system is designed to synchronize a given chaotic system with unknown parameters and external disturbances. Lyapunov stability ensures the global synchronization between the drive and response systems even if Lipschitz constants on function matrices and bounds on uncertainties are unknown. Numerical simulation of Genesio-Tesi system verifies the effectiveness of this scheme

  16. The synchronization of three fractional differential systems

    International Nuclear Information System (INIS)

    Li Changpin; Yan Jianping

    2007-01-01

    In this paper, a new method is proposed and applied to the synchronization of fractional differential systems (or 'differential systems with fractional orders'), where both drive and response systems have the same dimensionality and are coupled by the driving signal. The present technique is based on the stability criterion of linear fractional systems. This method is implemented in (chaos) synchronization of the fractional Lorenz system, Chen system and Chua circuit. Numerical simulations show the present synchronization method works well

  17. Complexity and synchronization in stochastic chaotic systems

    Science.gov (United States)

    Son Dang, Thai; Palit, Sanjay Kumar; Mukherjee, Sayan; Hoang, Thang Manh; Banerjee, Santo

    2016-02-01

    We investigate the complexity of a hyperchaotic dynamical system perturbed by noise and various nonlinear speech and music signals. The complexity is measured by the weighted recurrence entropy of the hyperchaotic and stochastic systems. The synchronization phenomenon between two stochastic systems with complex coupling is also investigated. These criteria are tested on chaotic and perturbed systems by mean conditional recurrence and normalized synchronization error. Numerical results including surface plots, normalized synchronization errors, complexity variations etc show the effectiveness of the proposed analysis.

  18. Impulsive synchronization of Chen's hyperchaotic system

    International Nuclear Information System (INIS)

    Haeri, Mohammad; Dehghani, Mahsa

    2006-01-01

    In this Letter the impulsive synchronization of the Chen's hyperchaotic systems is discussed. Some new and sufficient conditions on varying impulsive distance are established in order to guarantee the synchronizabillity of the systems using the synchronization method. In particular, some simple conditions are derived in synchronizing the systems by equal impulsive distances. Two illustrative examples are provided to show the feasibility and the effectiveness of the proposed method. The boundaries of the stable regions are also estimated

  19. Fitness for synchronization of network motifs

    DEFF Research Database (Denmark)

    Vega, Y.M.; Vázquez-Prada, M.; Pacheco, A.F.

    2004-01-01

    We study the synchronization of Kuramoto's oscillators in small parts of networks known as motifs. We first report on the system dynamics for the case of a scale-free network and show the existence of a non-trivial critical point. We compute the probability that network motifs synchronize, and fi...... that the fitness for synchronization correlates well with motifs interconnectedness and structural complexity. Possible implications for present debates about network evolution in biological and other systems are discussed....

  20. Synchronous Behavior of Two Coupled Biological Neurons

    International Nuclear Information System (INIS)

    Elson, R.C.; Selverston, A.I.; Elson, R.C.; Selverston, A.I.; Huerta, R.; Rulkov, N.F.; Rabinovich, M.I.; Abarbanel, H.D.; Selverston, A.I.; Huerta, R.; Abarbanel, H.D.

    1998-01-01

    We report experimental studies of synchronization phenomena in a pair of biological neurons that interact through naturally occurring, electrical coupling. When these neurons generate irregular bursts of spikes, the natural coupling synchronizes slow oscillations of membrane potential, but not the fast spikes. By adding artificial electrical coupling we studied transitions between synchrony and asynchrony in both slow oscillations and fast spikes. We discuss the dynamics of bursting and synchronization in living neurons with distributed functional morphology. copyright 1998 The American Physical Society

  1. Synchronization of weakly coupled canard oscillators

    OpenAIRE

    Köksal Ersöz, Elif; Desroches, Mathieu; Krupa, Martin

    2017-01-01

    International audience; Synchronization has been studied extensively in the context of weakly coupled oscillators using the so-called phase response curve (PRC) which measures how a change of the phase of an oscillator is affected by a small perturbation. This approach was based upon the work of Malkin, and it has been extended to relaxation oscillators. Namely, synchronization conditions were established under the weak coupling assumption, leading to a criterion for the existence of synchron...

  2. Integrability: mathematical methods for studying solitary waves theory

    Science.gov (United States)

    Wazwaz, Abdul-Majid

    2014-03-01

    In recent decades, substantial experimental research efforts have been devoted to linear and nonlinear physical phenomena. In particular, studies of integrable nonlinear equations in solitary waves theory have attracted intensive interest from mathematicians, with the principal goal of fostering the development of new methods, and physicists, who are seeking solutions that represent physical phenomena and to form a bridge between mathematical results and scientific structures. The aim for both groups is to build up our current understanding and facilitate future developments, develop more creative results and create new trends in the rapidly developing field of solitary waves. The notion of the integrability of certain partial differential equations occupies an important role in current and future trends, but a unified rigorous definition of the integrability of differential equations still does not exist. For example, an integrable model in the Painlevé sense may not be integrable in the Lax sense. The Painlevé sense indicates that the solution can be represented as a Laurent series in powers of some function that vanishes on an arbitrary surface with the possibility of truncating the Laurent series at finite powers of this function. The concept of Lax pairs introduces another meaning of the notion of integrability. The Lax pair formulates the integrability of nonlinear equation as the compatibility condition of two linear equations. However, it was shown by many researchers that the necessary integrability conditions are the existence of an infinite series of generalized symmetries or conservation laws for the given equation. The existence of multiple soliton solutions often indicates the integrability of the equation but other tests, such as the Painlevé test or the Lax pair, are necessary to confirm the integrability for any equation. In the context of completely integrable equations, studies are flourishing because these equations are able to describe the

  3. Shoaling internal solitary waves of depression over gentle slopes

    Science.gov (United States)

    Rivera, Gustavo; Diamessis, Peter

    2017-11-01

    The shoaling of an internal solitary wave (ISW) of depression over gentle slopes is explored through fully nonlinear and non-hydrostatic simulations using a high resolution/accuracy deformed spectral multidomain penalty method. During shoaling, the wave does not disintegrate as in the case of steeper slope but, instead, maintains its symmetric shape. At the core of the wave, an unstable region forms, characterized by the entrapment of heavier-over-light fluid. The formation of this convective instability is attributed to the vertical stretching by the ISW of the near-surface vorticity layer associated with the baroclinic background current. According to recent field observations in the South China Sea, the unstable region drives localized turbulent mixing within the wave, estimated to be up to four times larger than that in the open ocean, in the form of a recirculating trapped core. In this talk, emphasis is placed on the structure of the unstable region and the persistence of a possible recirculating core using simulations which capture 2D wave propagation combined with 3D representation of the transition to turbulence. As such, a preliminary understanding of the underlying fluid mechanics and the potential broader oceanic significance of ISWs with trapped cores is offered. Financial support gratefully acknowledged to NSF OCE Grant 1634257.

  4. MRI diagnosis of solitary fibrous tumor in the orbit

    International Nuclear Information System (INIS)

    Dong Jiyong; Yang Bentao; Zhang Wu; Wang Zhenchang; Xian Junfang

    2012-01-01

    Objective: To explore the MRI features of solitary fibrous tumor (SFT) in the orbit. Methods: The MRI findings of 7 patients with SFT in the orbit confirmed by histopathology were analyzed retrospectively. Results: Of the 7 lesions,5 occurred in the right orbit and 2 in the left orbit. Six lesions were located in the extraconal space near the lacrimal gland fossa, including 5 in the superomedial region and 1 in the inferolateral region. The other one was located in the retrobulbar intraconal space. The lesions with well-defined margin showed elliptic shape in 6 cases and lobulated configuration in 1. The maximum diameter of the lesions ranged from 18 to 40 mm (mean, 31 mm). The lesions showed homogeneous isointense relative to gray matter on T 1 -weighted images in 6 patients. On T 2 -weighted images, the lesions showed heterogeneous hypointense in 5 patients, isointense and hyperintense in one patient respectively. SFT demonstrated markedly homogeneous enhancement in 6 patients and inhomogeneous enhancement in one patient. The time-intensity curves (TIC) of 7 patients exhibited a rapidly enhancing and rapid washout pattern on dynamic contrast-enhanced (DCE) MRI. Conclusion: Hypointense signal on T 2 WI, marked enhancement on contrast-enhanced T 1 WI, and a rapidly enhancing and rapid washout pattern TIC on DCE MRI are the typical MRI features of orbital SFT. (authors)

  5. Antecubital Fossa Solitary Osteochondroma with Associated Bicipitoradial Bursitis

    Directory of Open Access Journals (Sweden)

    Colin Ng

    2015-01-01

    Full Text Available Antecubital fossa lesions are uncommon conditions that present to the orthopaedic clinic. Furthermore, the radius bone is an uncommonly reported location for an osteochondroma, especially when presenting with a concurrent reactive bicipitoradial bursitis. Osteochondromas are a type of developmental lesion rather than a true neoplasm. They constitute up to 15% of all bone tumours and up to 50% of benign bone tumours. They may occur as solitary or multiple lesions. Multiple lesions are usually associated with a syndrome known as hereditary multiple exostoses (HME. Malignant transformation is known to occur but is rare. Bicipitoradial bursitis is a condition which can occur as primary or secondary (reactive pathology. In our case, the radius bone osteochondroma caused reactive bicipitoradial bursitis. The differential diagnosis of such antecubital fossa masses is vast but may be narrowed down through a targeted history, stepwise radiological investigations, and histological confirmation. Our aim is to ensure that orthopaedic clinicians keep a wide differential in mind when dealing with antecubital fossa mass lesions.

  6. Electrostatic solitary waves in dusty pair-ion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Misra, A. P. [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan-731 235, West Bengal (India); Adhikary, N. C. [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Vigyan Path, Paschim Boragaon, Garchuk, Guwahati-781035, Assam (India)

    2013-10-15

    The propagation of electrostatic waves in an unmagnetized collisionless pair-ion plasma with immobile positively charged dusts is studied for both large- and small-amplitude perturbations. Using a two-fluid model for pair-ions, it is shown that there appear two linear ion modes, namely the “fast” and “slow” waves in dusty pair-ion plasmas. The properties of these wave modes are studied with different mass (m) and temperature (T) ratios of negative to positive ions, as well as the effects of immobile charged dusts (δ). For large-amplitude waves, the pseudopotential approach is performed, whereas the standard reductive perturbation technique is used to study the small-amplitude Korteweg-de Vries (KdV) solitons. The profiles of the pseudopotential, the large amplitude solitons as well as the dynamical evolution of KdV solitons, are numerically studied with the system parameters as above. It is found that the pair-ion plasmas with positively charged dusts support the propagation of solitary waves (SWs) with only the negative potential. The results may be useful for the excitation of SWs in laboratory dusty pair-ion plasmas, electron-free industrial plasmas as well as for observation in space plasmas where electron density is negligibly small compared to that of negative ions.

  7. Existence domain of electrostatic solitary waves in the lunar wake

    Science.gov (United States)

    Rubia, R.; Singh, S. V.; Lakhina, G. S.

    2018-03-01

    Electrostatic solitary waves (ESWs) and double layers are explored in a four-component plasma consisting of hot protons, hot heavier ions (He++), electron beam, and suprathermal electrons having κ-distribution using the Sagdeev pseudopotential method. Three modes exist: slow and fast ion-acoustic modes and electron-acoustic mode. The occurrence of ESWs and their existence domain as a function of various plasma parameters, such as the number densities of ions and electron beam, the spectral index, κ, the electron beam velocity, the temperatures of ions, and electron beam, are analyzed. It is observed that both the slow and fast ion-acoustic modes support both positive and negative potential solitons as well as their coexistence. Further, they support a "forbidden gap," the region in which the soliton ceases to propagate. In addition, slow ion-acoustic solitons support the existence of both positive and negative potential double layers. The electron-acoustic mode is only found to support negative potential solitons for parameters relevant to the lunar wake plasma. Fast Fourier transform of a soliton electric field produces a broadband frequency spectrum. It is suggested that all three soliton types taken together can provide a good explanation for the observed electrostatic waves in the lunar wake.

  8. Solitary Langmuir waves in two-electron temperature plasma

    Science.gov (United States)

    Prudkikh, V. V.; Prudkikh

    2014-06-01

    Nonlinear interaction of Langmuir and ion-acoustic waves in two-electron temperature plasma is investigated. New integrable wave interaction regime was discovered, this regime corresponds to the Langmuir soliton with three-hump amplitude, propagating with a speed close to the ion-sound speed in the conditions of strong non-isothermality of electronic components. It was discovered that besides the known analytical solution in the form of one- and two-hump waves, there exists a range of solutions in the form of solitary waves, which in the form of envelope has multi-peak structure and differs from the standard profiles described by hyperbolic functions. In case of fixed plasma parameters, different group velocities correspond to the waves with different number of peaks. It is found that the Langmuir wave package contains both even and uneven numbers of oscillations. Low-frequency potential here has uneven number of peaks. Interrelation of obtained and known earlier results are also discussed.

  9. Landau damping of dust acoustic solitary waves in nonthermal plasmas

    Science.gov (United States)

    Ghai, Yashika; Saini, N. S.; Eliasson, B.

    2018-01-01

    Dust acoustic (DA) solitary and shock structures have been investigated under the influence of Landau damping in a dusty plasma containing two temperature nonthermal ions. Motivated by the observations of Geotail spacecraft that reported two-temperature ion population in the Earth's magnetosphere, we have investigated the effect of resonant wave-particle interactions on DA nonlinear structures. The Korteweg-de Vries (KdV) equation with an additional Landau damping term is derived and its analytical solution is presented. The solution has the form of a soliton whose amplitude decreases with time. Further, we have illustrated the influence of Landau damping and nonthermality of the ions on DA shock structures by a numerical solution of the Landau damping modified KdV equation. The study of the time evolution of shock waves suggests that an initial shock-like pulse forms an oscillatory shock at later times due to the balance of nonlinearity, dispersion, and dissipation due to Landau damping. The findings of the present investigation may be useful in understanding the properties of nonlinear structures in the presence of Landau damping in dusty plasmas containing two temperature ions obeying nonthermal distribution such as in the Earth's magnetotail.

  10. Calculation principles for a synchronous electromagnetic clutch

    Science.gov (United States)

    Panasenkov, M. A.

    1978-01-01

    A detailed explanation of the calculation principles, for a synchronous salient-pole electromagnetic clutch with lumped excitation windings is supplied by direct current. Practical recommendations are given.

  11. Synchronized Data Aggregation for Wireless Sensor Network

    DEFF Research Database (Denmark)

    Dnyaneshwar, Mantri; Prasad, Neeli R.; Prasad, Ramjee

    2014-01-01

    Wireless Sensor Networks (WSNs) are used for monitoring and data collection purposes. A key challenge in effective data collection is to schedule and synchronize the activities of the nodes with global clock. This paper proposes the Synchronized Data Aggregation Algorithm (SDA) using spanning tree...... mechanism. It provides network-wide time synchronization for sensor network. In the initial stage algorithm established the hierarchical structure in the network and then perform the pair - wise synchronization. SDA aggregate data with a global time scale throughout the network. The aggregated packets...

  12. Coupled lasers: phase versus chaos synchronization.

    Science.gov (United States)

    Reidler, I; Nixon, M; Aviad, Y; Guberman, S; Friesem, A A; Rosenbluh, M; Davidson, N; Kanter, I

    2013-10-15

    The synchronization of chaotic lasers and the optical phase synchronization of light originating in multiple coupled lasers have both been extensively studied. However, the interplay between these two phenomena, especially at the network level, is unexplored. Here, we experimentally compare these phenomena by controlling the heterogeneity of the coupling delay times of two lasers. While chaotic lasers exhibit deterioration in synchronization as the time delay heterogeneity increases, phase synchronization is found to be independent of heterogeneity. The experimental results are found to be in agreement with numerical simulations for semiconductor lasers.

  13. Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Ruyue; Fang, Liaoqiong [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Xing, Ruoxi [Institute of Life Science, Chongqing Medical University, Chongqing 400016 (China); Xiong, Yu [Department of Obstetrics and Gynecology, Chongqing Hifu Hospital, Chongqing 401121 (China); Fang, Liaoqiong, E-mail: lqfang06@163.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Wang, Zhibiao, E-mail: wangzb@cqmu.edu.cn [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China)

    2015-12-04

    Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERα and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E{sub 2}) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E{sub 2} concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights: • In both

  14. Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

    International Nuclear Information System (INIS)

    Shao, Ruyue; Fang, Liaoqiong; Xing, Ruoxi; Xiong, Yu; Fang, Liaoqiong; Wang, Zhibiao

    2015-01-01

    Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERα and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E 2 ) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E 2 concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights: • In both multiple

  15. Adaptive synchronization of chaos in permanent magnet synchronous motors based on passivity theory

    International Nuclear Information System (INIS)

    Wei Du-Qu; Luo Xiao-Shu; Zhang Bo

    2012-01-01

    An adaptive synchronization control method is proposed for chaotic permanent magnet synchronous motors based on the property of a passive system. We prove that the controller makes the synchronization error system between the driving and the response systems not only passive but also asymptotically stable. The simulation results show that the proposed method is effective and robust against uncertainties in the systemic parameters. (general)

  16. Investigation of phase synchronization of interictal EEG in right temporal lobe epilepsy

    Science.gov (United States)

    Yu, Haitao; Cai, Lihui; Wu, Xinyu; Song, Zhenxi; Wang, Jiang; Xia, Zijie; Liu, Jing; Cao, Yibin

    2018-02-01

    Epilepsy is commonly associated with abnormally synchronous activity of neurons located in epileptogenic zones. In this study, we investigated the synchronization characteristic of right temporal lobe epilepsy (RTLE). Multichannel electroencephalography (EEG) data were recorded from the RTLE patients during interictal period and normal controls. Power spectral density was first used to analyze the EEG power for two groups of subjects. It was found that the power of epileptics is increased in the whole brain compared with that of the control. We calculated phase lag index (PLI) to measure the phase synchronization between each pair of EEG signals. A higher degree of synchronization was observed in the epileptics especially between distant channels. In particular, the regional synchronization degree was negatively correlated with power spectral density and the correlation was weaker for epileptics. Moreover, the synchronization degree decayed with the increase of relative distance of channels for both the epilepsy and control, but the dependence was weakened in the former. The obtained results may provide new insights into the generation mechanism of epilepsy.

  17. Isolated metachronous splenic metastasis from synchronous colon cancer

    Directory of Open Access Journals (Sweden)

    Aker Fugen

    2006-07-01

    Full Text Available Abstract Background Isolated splenic metastases from colorectal cancer are very rare and there are only 13 cases reported in the English literature so far. Most cases are asymptomatic and the diagnosis is usually made by imaging studies during the evaluation of rising CEA level postoperatively. Case presentation A 76-year-old man underwent an extended left hemicolectomy for synchronous colon cancers located at the left flexure and the sigmoid colon. The tumors were staged as IIIC (T3N2M0 clinically and the patient received adjuvant chemotherapy. During the first year follow-up period, the patient remained asymptomatic with normal levels of laboratory tests including CEA measurement. However, a gradually rising CEA level after the 14th postoperative month necessitated further imaging studies including computed tomography of the abdomen which revealed a mass in the spleen that was subsequently confirmed by 18FDG- PET scanning to be an isolated metastasis. The patient underwent splenectomy 17 months after his previous cancer surgery. Histological diagnosis confirmed a metastatic adenocarcinoma with no capsule invasion. After an uneventful postoperative period, the patient has been symptom-free during the one-year of follow-up with normal blood CEA levels, although he did not accept to receive any further adjuvant therapy. To the best of our knowledge, this 14th case of isolated splenic metastasis from colorectal carcinoma is also the first reported case of splenic metastasis demonstrated preoperatively by 18FDG PET-CT fusion scanning which revealed its solitary nature as well. Conclusion Isolated splenic metastasis is a rare finding in the follow-up of colorectal cancer patients and long-term survival can be achieved with splenectomy.

  18. [Hypoglycemia induced by a solitary fibrous tumor of the lung or Doege-Potter syndrome: Report of one case].

    Science.gov (United States)

    Soutelo, Jimena; Moldes, Sofía; Martin, Ayelén; Lutfi, Rubén; Leal Reyna, Mariela

    2016-01-01

    We report the case of a 75-year-old man who was admitted to the hospital with symptoms of severe hypoglycemia. He had a history of solitary fibrous tumor diagnosed by Pathology after its complete surgical resection eight years before. The laboratory examination reported hypoglycemia with inhibited Insulin secretion. A computed tomography of the thorax revealed a large solid heterogeneous mass in the left hemithorax. Solitary fibrous tumor is a rare neoplasm. The association of solitary fibrous tumor and paraneoplastic hypoglycemia is known as Doege-Potter syndrome and occurs in less than 5% of all solitary fibrous tumors.

  19. In the twinkling of an eye: synchronization of EEG and eye tracking based on blink signatures

    DEFF Research Database (Denmark)

    Bækgaard, Per; Petersen, Michael Kai; Larsen, Jakob Eg

    2014-01-01

    ACHIEVING ROBUST ADAPTIVE SYNCHRONIZATION OF MULTIMODAL BIOMETRIC INPUTS: The recent arrival of wireless EEG headsets that enable mobile real-time 3D brain imaging on smartphones, and low cost eye trackers that provide gaze control of tablets, will radically change how biometric sensors might...... be integrated into next generation user interfaces. In experimental lab settings EEG neuroimaging and eye tracking data are traditionally combined using external triggers to synchronize the signals. However, with biometric sensors increasingly being applied in everyday usage scenarios, there will be a need...

  20. Adaptive projective synchronization between different chaotic ...

    Indian Academy of Sciences (India)

    ... with adaptive projective synchronization between two different chaotic systems with parametric uncertainties and external disturbances. Based on Lyapunov stability theory, the projective synchronization between a pair of different chaotic systems with fully unknown parameters are derived. An adaptive control law and a ...

  1. Synchronization of oscillators in complex networks

    Indian Academy of Sciences (India)

    https://www.ias.ac.in/article/fulltext/pram/070/06/1175-1198 ... Abstract. Theory of identical or complete synchronization of identical oscillators in arbitrary networks is introduced. ... Combined theories are used to explore and compare three types of semirandom networks for their efficacy in synchronizing oscillators.

  2. A clock synchronization skeleton based on RTAI

    NARCIS (Netherlands)

    Huang, Y.; Visser, P.M.; Broenink, Johannes F.

    2006-01-01

    This paper presents a clock synchronization skeleton based on RTAI (Real Time Application Interface). The skeleton is a thin layer that provides unified but extendible interfaces to the underlying operating system, the synchronization algorithms and the upper level applications in need of clock

  3. Principal ideal languages and synchronizing automata

    OpenAIRE

    Gusev, Vladimir V.; Maslennikova, Marina I.; Pribavkina, Elena V.

    2013-01-01

    We study ideal languages generated by a single word. We provide an algorithm to construct a strongly connected synchronizing automaton for which such a language serves as the language of synchronizing words. Also we present a compact formula to calculate the syntactic complexity of this language.

  4. Global chaos synchronization of coupled parametrically excited ...

    Indian Academy of Sciences (India)

    u.vincent@tu-clausthal.de (U E Vincent); njahabdul@yahoo.com (A N Njah). MS received 24 March 2009; ... sufficient criteria for global asymptotic synchronization are derived from which an esti- mated critical coupling is ... ent concepts of synchronization, the reader is referred to the fundamental book by. Pikovsky et al [7].

  5. Synchronization of oscillators in complex networks

    Indian Academy of Sciences (India)

    Abstract. Theory of identical or complete synchronization of identical oscillators in arbitrary networks is introduced. In addition, several graph theory concepts and results that augment the synchronization theory and a tie in closely to random, semirandom, and regular networks are introduced. Combined theories are used to ...

  6. Development of a synchronous subset of AADL

    DEFF Research Database (Denmark)

    Filali, Mamoun; Lawall, Julia

    2010-01-01

    We study the definition and the mapping of an AADL subset: the so called synchronous subset. We show that the data port protocol used for delayed and immediate connections between periodic threads can be interpreted in a  synchronous way. In this paper, we formalize this interpretation and study...

  7. Synchronization in Quantum Key Distribution Systems

    Directory of Open Access Journals (Sweden)

    Anton Pljonkin

    2017-10-01

    Full Text Available In the description of quantum key distribution systems, much attention is paid to the operation of quantum cryptography protocols. The main problem is the insufficient study of the synchronization process of quantum key distribution systems. This paper contains a general description of quantum cryptography principles. A two-line fiber-optic quantum key distribution system with phase coding of photon states in transceiver and coding station synchronization mode was examined. A quantum key distribution system was built on the basis of the scheme with automatic compensation of polarization mode distortions. Single-photon avalanche diodes were used as optical radiation detecting devices. It was estimated how the parameters used in quantum key distribution systems of optical detectors affect the detection of the time frame with attenuated optical pulse in synchronization mode with respect to its probabilistic and time-domain characteristics. A design method was given for the process that detects the time frame that includes an optical pulse during synchronization. This paper describes the main quantum communication channel attack methods by removing a portion of optical emission. This paper describes the developed synchronization algorithm that takes into account the time required to restore the photodetector’s operation state after the photon has been registered during synchronization. The computer simulation results of the developed synchronization algorithm were analyzed. The efficiency of the developed algorithm with respect to synchronization process protection from unauthorized gathering of optical emission is demonstrated herein.

  8. Modified function projective combination synchronization of ...

    Indian Academy of Sciences (India)

    2017-02-08

    Feb 8, 2017 ... Introduction. Since the concept of synchronizing two identical chaotic systems from different initial conditions was ... tography, secure communications [6,7], etc. Many ap- proaches have been proposed for the synchronization ... more secure communication. Hyperchaotic systems characterized by more than.

  9. Control of partial synchronization in chaotic oscillators

    Indian Academy of Sciences (India)

    2015-02-07

    Feb 7, 2015 ... Abstract. A design of coupling is proposed to control partial synchronization in two chaotic oscil- lators in a driver–response mode. A control of synchrony between one response variables is made possible (a transition from a complete synchronization to antisynchronization via amplitude death and vice ...

  10. Modified function projective combination synchronization of ...

    Indian Academy of Sciences (India)

    2017-02-08

    Feb 8, 2017 ... Abstract. In this work, a novel combination synchronization scheme in which synchronization of a new combination hyperchaotic drive system formed by combining state variables of the original drive system with appropriate scaling factors with a response hyperchaotic system is considered.

  11. Analytical treatment for synchronizing chaos through unidirectional ...

    Indian Academy of Sciences (India)

    Driving a nonlinear system with a periodic signal is a common feature in nonlinear dynamics. However, the idea of using a chaotic signal to drive a nonlinear system and to maintain synchronization in phase and amplitude of the driving and the driven systems is rather new. The idea of synchronizing two identical chaotic ...

  12. Synchronization of indirectly coupled Lorenz oscillators: An ...

    Indian Academy of Sciences (India)

    Partial synchronization occurs in a population of chemical oscillators coupled through the concentration of chemical in the surrounding solutions [19]. Two nonlinear chaotic systems coupled indirectly through a common dynamic environment synchronize to in-phase or anti-phase state [20]. The early stages of Alzheimer's ...

  13. Electrotonic vascular signal conduction and nephron synchronization

    DEFF Research Database (Denmark)

    Marsh, D.J.; Toma, I.; Sosnovtseva, Olga

    2009-01-01

    frequencies of both pair members to converge to a common value. The myogenic oscillations also synchronized, and the synchronization between the TGF and the myogenic oscillations showed an increased stability against parameter perturbations. Electronic vascular signal propagation is a plausible mechanism...

  14. The hippocampus: hub of brain network communication for memory.

    NARCIS (Netherlands)

    Battaglia, F.P.; Benchenane, K.; Sirota, A.; Pennartz, C.M.A.; Wiener, S.I.

    2011-01-01

    A complex brain network, centered on the hippocampus, supports episodic memories throughout their lifetimes. Classically, upon memory encoding during active behavior, hippocampal activity is dominated by theta oscillations (6-10Hz). During inactivity, hippocampal neurons burst synchronously,

  15. Juvenile polyps: recurrence in patients with multiple and solitary polyps.

    Science.gov (United States)

    Fox, Victor L; Perros, Stephen; Jiang, Hongyu; Goldsmith, Jeffrey D

    2010-09-01

    Juvenile polyps are benign hamartomas with neoplastic potential that are the most frequent gastrointestinal polyp of childhood. Most information about juvenile polyps in childhood comes from small published series that lack detailed outcome data. We sought to identify a large cohort of children with one or more polyps and analyze clinical characteristics, including polyp recurrence, which might contribute to the development of management guidelines. A retrospective chart review study of patients with juvenile polyps of the colon was performed. Cases were identified by searching a single hospital pathology database from 1990 to 2009 for the diagnosis of juvenile polyps. Recorded information included basic demographics, family history, genetic testing, and colonoscopy and pathology reports. A total of 257 children (median age, 5.6 y; 61.5% male) with juvenile polyps were identified. Among 192 patients who underwent complete colonoscopy at initial diagnosis, 117 (60.9%) had a single polyp, 75 (39.1%) had multiple polyps, 8 (4.2%) had polyps restricted to the right colon, and a total of 1653 polyps were found during 350 colonoscopy examinations. Polyps recurred in 21 of 47 (44.7%) patients after initial eradication, including 3 (16.7%) of 18 presenting with a single polyp. Neoplasia was found in 10 of 257 (3.9%) patients (right colon in 7 patients). Germline DNA abnormalities in mothers against decapentaplegic Drosophila (SMAD4), bone morphogenetic protein receptor 1A (BMPR1A), and phosphatase and tensin homolog (PTEN) were detected in 10 of 23 (43.5%) patients with multiple polyps. Recurrent polyp formation is common in children with juvenile polyps and occurs in patients with multiple and solitary polyps. Standardized protocols for detecting polyp recurrence, associated gene mutations, and neoplasia should be developed for children with juvenile polyps. Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

  16. Solitary juvenile polyps in children and colon cancer.

    Science.gov (United States)

    Kapetanakis, A M; Vini, D; Plitsis, G

    1996-01-01

    Solitary Juvenile Polyps (SJP) are quite common in preschool children, although they may occur at any age. It is not known whether the existence of a single juvenile polyp in a child predisposes to future development of new SJP or is related to colorectal neoplasia. The present study was designed to follow up young patients who had undergone polypectomy for SJP and their first degree relatives to elucidate the development of adenomatous polyps or colon cancer. From 31 children polypectomized for histologically proven SJP between 1983-1995, we were able to contact and gather information on 24. From our records and the information collected we studied age, gender, site of the polyp in the bowel, personal history, and family history. Mean time of follow up was 4.1 years (range 0.4-10, SD +/- 3.1) Mean age was 4.6 years (Range 3.5-9, SD +/- 1.2). There were 14 boys and 10 girls (ratio 1.4/1). Eighteen polyps were located at the rectosigmoid area, 5 in the lower descending colon, and one in the splenic flecture. From the 24 children, only one girl developed rectal bleeding at the age of 15 years, 8 years after polypectomy. However, subsequent evidence from the large bowel did not reveal any abnormality and the symptom was attributed to hemorrhoidal bleeding. Thorough investigation of the history of 146 first degree relatives (dead or alive) siblings, parents, and grandparents revealed that none of them were diagnosed with adenomatous polyps or colorectal cancer. SJP does not predispose to future development of new juvenile polyps and is not associated with a high risk of colorectal malignancy.

  17. Solitary Tracheobronchial Papilloma: Cytomorphology and ancillary studies with histologic correlation

    Directory of Open Access Journals (Sweden)

    Tee U Lang

    2011-01-01

    Full Text Available Solitary tracheobronchial papilloma (STBP is a rare benign tumor that primarily involves the tracheobronchial tree. Human papilloma virus (HPV infection is associated with dysplasia and a high risk of carcinoma in these lesions. The cytomorphology of STBP is not well established in the literature. Our aim is to characterize the cytomorphologic features of STBP, with histologic correlation in a series of 6 patients - 4 males and 2 females - with a mean age of 67 years (range, 53-88 years. There were 5 biopsy-proven squamous papillomas and 1 glandular papilloma. On surgical biopsy, squamous papillomas exhibited cytological atypia (4 graded mild and 1 graded moderate with focal severe dysplasia, surface erosion, and inflammation. Cytology specimens available for review included a combination of 4 fine-needle aspirations (FNAs, 2 bronchoalveolar lavages and 2 (of 3 bronchial brushings. Cytologic findings associated with squamous papillomas included atypical squamous cells and rare squamous cell resembling koilocyte in 1 bronchial brushing. Sheets of squamous cells were identified in another specimen. Several cases had a prominent background of acute inflammation, and candida was present in 1 specimen. HPV in-situ hybridization was positive in 1 case and negative in 2 cases. A p16 immunocytochemical stain performed on 1 cell block was negative. In conclusion, although STBP is a rare neoplasm, these cases may be encountered in respiratory cytology samples. FNA of papillomas yields fewer lesional cells compared to exfoliative samples. These lesions may be mistaken in cytology specimens for squamous cell carcinoma, squamous-lined cavitary lesions, an infectious (fungal process, reactive squamous metaplasia, or oral contamination.

  18. Communicating via robust synchronization of chaotic lasers

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Gutierrez, R.M. [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico); Posadas-Castillo, C. [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico); FIME, Autonomous University of Nuevo Leon (UANL), Pedro de Alba, S.N., Cd. Universitaria, San Nicolas de los Garza, NL (Mexico); Lopez-Mancilla, D. [Departamento de Ciencias Exactas y Tecnologicas, Centro Universitario de los Lagos, Universidad de Guadalajara (CULagos-UdeG), Enrique Diaz de Leon s/n, 47460 Lagos de Moreno, Jal. (Mexico); Cruz-Hernandez, C. [Electronics and Telecommunications Department, Scientific Research and Advanced Studies of Ensenada (CICESE), Km. 107 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico)], E-mail: ccruz@cicese.mx

    2009-10-15

    In this paper, the robust synchronization problem for coupled chaotic Nd:YAG lasers is addressed. We resort to complex systems theory to achieve chaos synchronization. Based on stability theory, it is shown that the state trajectories of the perturbed error synchronization are ultimately bounded, provided the unperturbed synchronization error system is exponentially stable, and some conditions on the bounds of the perturbation terms are satisfied. So that, encoding, transmission, and decoding in chaotic optical communications are presented. We analyze the transmission and recovery of encrypted information when parameter mismatches are considered. Computer simulations are provided to show the effectiveness of this robustness synchronization property, we present the encrypted transmission of image messages, and we show that, the transmitted image is faithfully recovered.

  19. Communicating via robust synchronization of chaotic lasers

    International Nuclear Information System (INIS)

    Lopez-Gutierrez, R.M.; Posadas-Castillo, C.; Lopez-Mancilla, D.; Cruz-Hernandez, C.

    2009-01-01

    In this paper, the robust synchronization problem for coupled chaotic Nd:YAG lasers is addressed. We resort to complex systems theory to achieve chaos synchronization. Based on stability theory, it is shown that the state trajectories of the perturbed error synchronization are ultimately bounded, provided the unperturbed synchronization error system is exponentially stable, and some conditions on the bounds of the perturbation terms are satisfied. So that, encoding, transmission, and decoding in chaotic optical communications are presented. We analyze the transmission and recovery of encrypted information when parameter mismatches are considered. Computer simulations are provided to show the effectiveness of this robustness synchronization property, we present the encrypted transmission of image messages, and we show that, the transmitted image is faithfully recovered.

  20. Synchronization in networks with heterogeneous coupling delays

    Science.gov (United States)

    Otto, Andreas; Radons, Günter; Bachrathy, Dániel; Orosz, Gábor

    2018-01-01

    Synchronization in networks of identical oscillators with heterogeneous coupling delays is studied. A decomposition of the network dynamics is obtained by block diagonalizing a newly introduced adjacency lag operator which contains the topology of the network as well as the corresponding coupling delays. This generalizes the master stability function approach, which was developed for homogenous delays. As a result the network dynamics can be analyzed by delay differential equations with distributed delay, where different delay distributions emerge for different network modes. Frequency domain methods are used for the stability analysis of synchronized equilibria and synchronized periodic orbits. As an example, the synchronization behavior in a system of delay-coupled Hodgkin-Huxley neurons is investigated. It is shown that the parameter regions where synchronized periodic spiking is unstable expand when increasing the delay heterogeneity.

  1. Effects of frustration on explosive synchronization

    Science.gov (United States)

    Huang, Xia; Gao, Jian; Sun, Yu-Ting; Zheng, Zhi-Gang; Xu, Can

    2016-12-01

    In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.

  2. Variance based OFDM frame synchronization

    Directory of Open Access Journals (Sweden)

    Z. Fedra

    2012-04-01

    Full Text Available The paper deals with a new frame synchronization scheme for OFDM systems and calculates the complexity of this scheme. The scheme is based on the computing of the detection window variance. The variance is computed in two delayed times, so a modified Early-Late loop is used for the frame position detection. The proposed algorithm deals with different variants of OFDM parameters including guard interval, cyclic prefix, and has good properties regarding the choice of the algorithm's parameters since the parameters may be chosen within a wide range without having a high influence on system performance. The verification of the proposed algorithm functionality has been performed on a development environment using universal software radio peripheral (USRP hardware.

  3. Synchronization of nonautonomous dynamical systems

    Directory of Open Access Journals (Sweden)

    Peter E. Kloeden

    2003-04-01

    Full Text Available The synchronization of two nonautonomous dynamical systems is considered, where the systems are described in terms of a skew-product formalism, i. e., in which an inputed autonomous driving system governs the evolution of the vector field of a differential equation with the passage of time. It is shown that the coupled trajectories converge to each other as time increases for sufficiently large coupling coefficient and also that the component sets of the pullback attractor of the coupled system converges upper semi continuously as the coupling parameter increases to the diagonal of the product of the corresponding component sets of the pullback attractor of a system generated by the average of the vector fields of the original uncoupled systems.

  4. Synchronization of world economic activity

    Science.gov (United States)

    Groth, Andreas; Ghil, Michael

    2017-12-01

    Common dynamical properties of business cycle fluctuations are studied in a sample of more than 100 countries that represent economic regions from all around the world. We apply the methodology of multivariate singular spectrum analysis (M-SSA) to identify oscillatory modes and to detect whether these modes are shared by clusters of phase- and frequency-locked oscillators. An extension of the M-SSA approach is introduced to help analyze structural changes in the cluster configuration of synchronization. With this novel technique, we are able to identify a common mode of business cycle activity across our sample, and thus point to the existence of a world business cycle. Superimposed on this mode, we further identify several major events that have markedly influenced the landscape of world economic activity in the postwar era.

  5. Phase synchronization in electroencephalographic recordings prognosticates outcome in paediatric coma.

    Directory of Open Access Journals (Sweden)

    Vera Nenadovic

    Full Text Available Brain injury from trauma, cardiac arrest or stroke is the most important cause of death and acquired disability in the paediatric population. Due to the lifetime impact of brain injury, there is a need for methods to stratify patient risk and ultimately predict outcome. Early prognosis is fundamental to the implementation of interventions to improve recovery, but no clinical model as yet exists. Healthy physiology is associated with a relative high variability of physiologic signals in organ systems. This was first evaluated in heart rate variability research. Brain variability can be quantified through electroencephalographic (EEG phase synchrony. We hypothesised that variability in brain signals from EEG recordings would correlate with patient outcome after brain injury. Lower variability in EEG phase synchronization, would be associated with poor patient prognosis. A retrospective study, spanning 10 years (2000-2010 analysed the scalp EEGs of children aged 1 month to 17 years in coma (Glasgow Coma Scale, GCS, <8 admitted to the paediatric critical care unit (PCCU following brain injury from TBI, cardiac arrest or stroke. Phase synchrony of the EEGs was evaluated using the Hilbert transform and the variability of the phase synchrony calculated. Outcome was evaluated using the 6 point Paediatric Performance Category Score (PCPC based on chart review at the time of hospital discharge. Outcome was dichotomized to good outcome (PCPC score 1 to 3 and poor outcome (PCPC score 4 to 6. Children who had a poor outcome following brain injury secondary to cardiac arrest, TBI or stroke, had a higher magnitude of synchrony (R index, a lower spatial complexity of the synchrony patterns and a lower temporal variability of the synchrony index values at 15 Hz when compared to those patients with a good outcome.

  6. Genetic and epigenetic profiling of a solitary Peutz-Jeghers colon polyp.

    Science.gov (United States)

    Linhart, Heinz; Bormann, Felix; Hutter, Barbara; Brors, Benedikt; Lyko, Frank

    2017-05-01

    Colon polyps represent precursor lesions of colon cancers and their malignant potential varies according to histological subtype. A rare subtype of colon polyps is the Peutz-Jeghers (PJ) polyp. PJ polyps mostly occur in the context of Peutz-Jeghers syndrome, which is characterized by the development of multiple polyps in the intestinal tract and hyperpigmentation of oral mucosa and lips. Peutz-Jeghers is an autosomal dominant disorder caused by pathogenic variants of the serine threonine kinase STK11. PJ polyps very rarely occur outside of the syndrome and are then referred to as solitary PJ polyps. Contrary to the situation in Peutz-Jeghers, the genetic basis and the malignant potential of solitary PJ polyps are currently unknown. Here we describe a detailed and comprehensive genetic profile of a solitary PJ polyp. Pathological examination revealed a high tissue homogeneity with >80% epithelial cells. Whole-genome sequencing failed to identify any clonal mutations but demonstrated a significant number of subclonal mutations. No somatic or germline mutations were found at the STK11 locus, suggesting that solitary PJ polyps are genetically distinct from Peutz-Jeghers polyps. In addition, methylome analysis revealed global hypomethylation and CpG island hypermethylation, two features that have been described as hallmarks of the colorectal cancer epigenome. These results provide an example of a premalignant lesion that is defined by epigenetic, rather than genetic changes. Furthermore, our findings support the notion that solitary PJ polyps constitute neoplastic tissue with malignant potential that should be removed for cancer prevention.

  7. Brain Basics

    Medline Plus

    Full Text Available ... About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain Brain ... called the hypothalamic-pituitary-adrenal (HPA) axis. Brain Basics in Real Life Brain Basics in Real Life— ...

  8. Chaos synchronization between Chen system and Genesio system

    International Nuclear Information System (INIS)

    Wu Xianyong; Guan Zhihong; Wu Zhengping; Li Tao

    2007-01-01

    This Letter presents two synchronization schemes between two different chaotic systems. Active control synchronization and adaptive synchronization between Chen system and Genesio system are studied, different controllers are designed to synchronize the drive and response systems, active control synchronization is used when system parameters are known; adaptive synchronization is employed when system parameters are unknown or uncertain. Simulation results show the effectiveness of the proposed schemes

  9. Emergent synchronous bursting of oxytocin neuronal network.

    Directory of Open Access Journals (Sweden)

    Enrico Rossoni

    2008-07-01

    Full Text Available When young suckle, they are rewarded intermittently with a let-down of milk that results from reflex secretion of the hormone oxytocin; without oxytocin, newly born young will die unless they are fostered. Oxytocin is made by magnocellular hypothalamic neurons, and is secreted from their nerve endings in the pituitary in response to action potentials (spikes that are generated in the cell bodies and which are propagated down their axons to the nerve endings. Normally, oxytocin cells discharge asynchronously at 1-3 spikes/s, but during suckling, every 5 min or so, each discharges a brief, intense burst of spikes that release a pulse of oxytocin into the circulation. This reflex was the first, and is perhaps the best, example of a physiological role for peptide-mediated communication within the brain: it is coordinated by the release of oxytocin from the dendrites of oxytocin cells; it can be facilitated by injection of tiny amounts of oxytocin into the hypothalamus, and it can be blocked by injection of tiny amounts of oxytocin antagonist. Here we show how synchronized bursting can arise in a neuronal network model that incorporates basic observations of the physiology of oxytocin cells. In our model, bursting is an emergent behaviour of a complex system, involving both positive and negative feedbacks, between many sparsely connected cells. The oxytocin cells are regulated by independent afferent inputs, but they interact by local release of oxytocin and endocannabinoids. Oxytocin released from the dendrites of these cells has a positive-feedback effect, while endocannabinoids have an inhibitory effect by suppressing the afferent input to the cells.

  10. Solitary fibrous tumor of the male breast: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Sessa Fausto

    2008-02-01

    Full Text Available Abstract Extrapleural solitary fibrous tumors are very rare and occasionally they appear in extraserosal soft tissues or parenchymatous organs. In such cases the right preoperative diagnosis is often difficult and challenging, because both radiological and cytological examinations are not exhaustive. For these reasons, surgical excision is frequently the only way to reach the correct diagnosis and to achieve definitive treatment. A few cases of solitary fibrous tumors have been also described in the breast. Although rare, this lesion opens difficulties in preoperative diagnosis entering in differential diagnosis with other benign lesions as well as with breast cancer. In this article we describe a case of a solitary fibrous tumor of the breast in a 49-year-old man. Problems related to differential diagnosis and the possible pitfalls that can be encountered in the diagnostic iter of such rare tumor are discussed.

  11. Relationship between serum TSH and the responsiveness of toxic solitary autonomous thyroid nodules to radioiodine therapy

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, U; Kirkegaard, B C

    1998-01-01

    OBJECTIVE: To investigate if serum TSH at the time of 131I therapy influences the outcome. DESIGN: A retrospective analysis of data on 39 consecutive patients with toxic solitary autonomous thyroid nodules treated with 131I during a 4 year period. METHODS: Serum TSH was determined by an ultrasens......OBJECTIVE: To investigate if serum TSH at the time of 131I therapy influences the outcome. DESIGN: A retrospective analysis of data on 39 consecutive patients with toxic solitary autonomous thyroid nodules treated with 131I during a 4 year period. METHODS: Serum TSH was determined...... hypothyroidism both had detectable serum TSH at the time of 131I treatment. No other clinical parameter seemed to influence the outcome. CONCLUSION: There is no clinically significant effect of circulating TSH on the response of toxic solitary autonomous thyroid nodules to 131I therapy. However, keeping...

  12. Solitary waves on inclined films: their characteristics and the effects on wall shear stress

    Energy Technology Data Exchange (ETDEWEB)

    Tihon, J. [Academy of Sciences of the Czech Republic, Institute of Chemical Process Fundamentals, Prague 6 (Czech Republic); Serifi, K.; Argyriadi, K.; Bontozoglou, V. [University of Thessaly, Department of Mechanical and Industrial Engineering, Volos (Greece)

    2006-07-15

    The properties of solitary waves, developing from inlet disturbances of controlled frequency along an inclined film flow, are systematically studied experimentally and computationally. Time-variations of film height and wall shear stress are measured, using respectively a capacitance probe and an electrodiffusion sensor. Computational data are provided from simulations performed by a Galerkin finite element scheme. The height and spacing of solitary humps, their phase velocity and the wavelength of the preceding capillary ripples are reported as functions of the Reynolds number (10solitary waves is studied experimentally and computationally as a function of Re. Distinct nonlinear characteristics are noted, including a steep maximum and a negative minimum, with the effects intensifying at intermediate Re. All computer predictions are found to be in good quantitative agreement with the experimental data. (orig.)

  13. Synchronization of Estrus in Cattle: A Review

    Directory of Open Access Journals (Sweden)

    R. Islam

    2011-06-01

    Full Text Available Numbers of estrus synchronization programmes are available in cattle based on the use of various hormones like progesterone, prostaglandin F2a and their various combinations with other hormones like estrogen and Gonadotrophin Releasing hormone (GnRH. Selection of appropriate estrus synchronization protocol should be made on the basis of management capabilities and expectations of the farmer. Synchronization of oestrus can be accomplished with the injection of prostaglandin F2a alone, but it needs proper detection of the ovarian status of the cows as prostaglandin F2a is active in only functional corpus luteum in between 8 to 17 days of estrous cycle. Progesterone may reduce fertility up to 14 percent, but short time progesterone exposure (less than 14 days is beneficial. Addition of GnRH in the Progesterone or Prostaglandin based synchronization programme is helpful for more synchrony in estrus as GnRH may be helpful to synchronize the oestrous cycle in delayed pubertal heifers and post partum cows (Post partum anoestrum and further a single, timed artificial insemination is possible with this method. New methods of synchronizing estrus in which the GnRH-PG protocol is preceded by progesterone treatment offer effective synchronization of estrus with high fertility. [Vet. World 2011; 4(3.000: 136-141

  14. Periodic and aperiodic synchronization in skilled action

    Directory of Open Access Journals (Sweden)

    Fred eCummins

    2011-12-01

    Full Text Available Synchronized action is considered as a manifestation of shared skill. Most synchronized behaviors in humans and other animals are based on periodic repetition. Aperiodic synchronization of complex action is found in the experimental task of synchronous speaking, in which naive subjects read a common text in lock step. The demonstration of synchronized behavior without a periodic basis is presented as a challenge for theoretical understanding. A unified treatment of periodic and aperiodic synchronization is suggested by replacing the sequential processing model of cognitivist approaches with the more local notion of a task-specific sensorimotor coordination. On this view, skilled action is the imposition of constraints on the co-variation of movement and sensory flux such that the boundary conditions that define the skill are met. This non-cognitivist approach originates in the work of John Dewey. It allows a unification of the treatment of sensorimotor synchronization in simple rhythmic behavior and in complex skilled behavior and it suggests that skill sharing is a uniquely human trait of considerable import.

  15. V123 Beam Synchronous Encoder Module

    International Nuclear Information System (INIS)

    Kerner, T.; Conkling, C. R.; Oerter, B.

    1999-01-01

    The V123 Synchronous Encoder Module transmits events to distributed trigger modules and embedded decoders around the RHIC rings where they are used to provide beam instrumentation triggers [1,2,3]. The RHIC beam synchronous event link hardware is mainly comprised of three VMEbus board designs, the central input modules (V201), and encoder modules (V123), and the distributed trigger modules (V124). Two beam synchronous links, one for each ring, are distributed via fiberoptic and fanned out via twisted wire pair cables. The V123 synchronizes with the RF system clock derived from the beam bucket frequency and a revolution fiducial pulse. The RF system clock is used to create the beam synchronous event link carrier and events are synchronized with the rotation fiducial. A low jitter RF clock is later recovered from this carrier by phase lock loops in the trigger modules. Prioritized hardware and software triggers fill up to 15 beam event code transmission slots per revolution while tracking the ramping RF acceleration frequency and storage frequency. The revolution fiducial event is always the first event transmitted which is used to synchronize the firing of the abort kicker and to locate the first bucket for decoders distributed about the ring

  16. Ambulatory blood pressure monitoring is recommended in the clinical management of children with a solitary functioning kidney

    NARCIS (Netherlands)

    Westland, R.; Schreuder, M.F.; Lof, D.F. van der; Vermeulen, A.; Meer, I.M. van der; Bokenkamp, A.; Wijk, J.A. van

    2014-01-01

    BACKGROUND: Children with a solitary functioning kidney are at increased risk of developing chronic kidney disease. Hypertension may be an early indicator of renal dysfunction in these patients. We determined blood pressure (BP) profiles of children with a solitary functioning kidney by using

  17. The Comparison of Solitary and Collaborative Modes of Game-Based Learning on Students' Science Learning and Motivation

    Science.gov (United States)

    Chen, Ching-Huei; Wang, Kuan-Chieh; Lin, Yu-Hsuan

    2015-01-01

    In this study, we investigated and compared solitary and collaborative modes of game-based learning in promoting students' science learning and motivation. A total of fifty seventh grade students participated in this study. The results showed that students who played in a solitary or collaborative mode demonstrated improvement in learning…

  18. Defining Pleasure: A Focus Group Study of Solitary and Partnered Sexual Pleasure in Queer and Heterosexual Women.

    Science.gov (United States)

    Goldey, Katherine L; Posh, Amanda R; Bell, Sarah N; van Anders, Sari M

    2016-11-01

    Solitary and partnered sexuality are typically depicted as fundamentally similar, but empirical evidence suggests they differ in important ways. We investigated how women's definitions of sexual pleasure overlapped and diverged when considering solitary versus partnered sexuality. Based on an interdisciplinary literature, we explored whether solitary pleasure would be characterized by eroticism (e.g., genital pleasure, orgasm) and partnered pleasure by nurturance (e.g., closeness). Via focus groups with a sexually diverse sample of women aged 18-64 (N = 73), we found that women defined solitary and partnered pleasure in both convergent and divergent ways that supported expectations. Autonomy was central to definitions of solitary pleasure, whereas trust, giving pleasure, and closeness were important elements of partnered pleasure. Both solitary and partnered pleasure involved exploration for self-discovery or for growing a partnered relationship. Definitions of pleasure were largely similar across age and sexual identity; however, relative to queer women, heterosexual women (especially younger heterosexual women) expressed greater ambivalence toward solitary masturbation and partnered orgasm. Results have implications for women's sexual well-being across multiple sexual identities and ages, and for understanding solitary and partnered sexuality as overlapping but distinct constructs.

  19. Physiological Synchronization in a Vigilance Dual Task.

    Science.gov (United States)

    Guastello, Stephen J

    2016-01-01

    The synchronization of autonomic arousal levels and other physio-logical responses between people is a potentially important component of work team performance, client-therapist relationships, and other types of human interaction. This study addressed several problems: What statistical models are viable for identifying synchronization for loosely coupled human systems? How is the level of synchronization related to psychosocial variables such as empathy, subjective ratings of workload, and actual performance? Participants were 70 undergraduates who worked in pairs on a vigilance dual task in which they watched a virtual reality security camera, rang a bell when they saw the target intruder, and completed a jig-saw puzzle. Event rates either increased or decreased during the 90 min work period. The average R2 values for each person were .66, .66, .62, and .53 for the linear autoregressive model, linear autoregressive model with a synchronization component, the nonlinear autoregressive model, and the nonlinear autoregressive model with a synchronization component, respectively. All models were more accurate at a lag of 20 sec compared to 50 sec or customized lag lengths. Although the linear models were more accurate overall, the nonlinear synchronization parameters were more often related to psychological variables and performance. In particular, greater synchronization was observed with the nonlinear model when the target event rate increased, compared to when it decreased, which was expected from the general theory of synchronization. Nonlinear models were also more effective for uncovering inhibitory or dampening relationships between the co-workers as well as mutually excitatory relationships. Future research should explore the comparative model results for tasks that induce higher levels of synchronization and involve different types of internal group coordination.

  20. Solitary Fibrous Tumour of the Pleura – Cases Analysis

    International Nuclear Information System (INIS)

    Jadczak, Przemysław; Guz, Wiesław; Kaznowska, Ewa; Ramotowski, Radosław; Szalacha-Tarała, Ewa; Górecki, Andrzej; Samojedny, Antoni

    2014-01-01

    Isolated fibrous tumor of the pleura (SFTP – Solitary fibrous tumour of the pleura/localized fibrous tumour of the pleura) is a rare primary tumour of the pleura of mesenchymal origin. In most cases, it is a benign lesion. It is composed of spindle cells similar to fibroblasts and derives probably from submesothelial mesenchyme. The aim of the study was to analyze clinical symptoms, incidence, possibility of suggesting the diagnosis on the basis of imaging tests, and confirmation of the diagnosis in pathological tests with regard to studies of histochemistry examination. Clinical and morphological material obtained from 14 patients from Department of Thoracic Surgery of Subcarpathian Chest Disease Center treated between year 2004 and 2010 was analysed. In the first stage, selected cases of patients with isolated fibrous tumour of the pleura were chosen from the archives and the analysis of their medical history was carried out. Basic information about age, gender, medical history, smoking habit, physical examination and results of imaging, endoscopic and morphological examinations were noted. The second parallel component of the study was pathomorphological examinations of the surgical material obtained from the patients, including the assessment of morphology and immunohistochemistry. Of the 14 examined patients, fibrous tumour occurred in 8 men and 6 women. The age range of the patients was 37–73 years, with a peak attributable to the 6 th decade of life. In 8 patients the tumour was detected incidentally during routine examinations. In 7 patients there were no clinical signs of respiratory disease, and if present, then the most common complaint was shortness of breath. Regarding symptoms not connected with the respiratory system, anemia occurred most frequently. Fibrous tumour of the pleura was more often associated with the visceral pleura than with the parietal pleura. The largest lesion was approximately 20 cm in size. Fibrous tumour of the pleura is a