Bibliografías temáticas / Spike detector

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Literatura académica sobre el tema "Spike detector"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 29 de enero de 2023

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Artículos de revistas sobre el tema "Spike detector"

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Kramer, Mark A., Lauren M. Ostrowski, Daniel Y. Song, Emily L. Thorn, Sally M. Stoyell, McKenna Parnes, Dhinakaran Chinappen et al. "Scalp recorded spike ripples predict seizure risk in childhood epilepsy better than spikes". Brain 142, n.º 5 (25 de marzo de 2019): 1296–309. http://dx.doi.org/10.1093/brain/awz059.

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Abstract In the past decade, brief bursts of fast oscillations in the ripple range have been identified in the scalp EEG as a promising non-invasive biomarker for epilepsy. However, investigation and clinical application of this biomarker have been limited because standard approaches to identify these brief, low amplitude events are difficult, time consuming, and subjective. Recent studies have demonstrated that ripples co-occurring with epileptiform discharges (‘spike ripple events’) are easier to detect than ripples alone and have greater pathological significance. Here, we used objective techniques to quantify spike ripples and test whether this biomarker predicts seizure risk in childhood epilepsy. We evaluated spike ripples in scalp EEG recordings from a prospective cohort of children with a self-limited epilepsy syndrome, benign epilepsy with centrotemporal spikes, and healthy control children. We compared the rate of spike ripples between children with epilepsy and healthy controls, and between children with epilepsy during periods of active disease (active, within 1 year of seizure) and after a period of sustained seizure-freedom (seizure-free, >1 year without seizure), using semi-automated and automated detection techniques. Spike ripple rate was higher in subjects with active epilepsy compared to healthy controls (P = 0.0018) or subjects with epilepsy who were seizure-free ON or OFF medication (P = 0.0018). Among epilepsy subjects with spike ripples, each month seizure-free decreased the odds of a spike ripple by a factor of 0.66 [95% confidence interval (0.47, 0.91), P = 0.021]. Comparing the diagnostic accuracy of the presence of at least one spike ripple versus a classic spike event to identify group, we found comparable sensitivity and negative predictive value, but greater specificity and positive predictive value of spike ripples compared to spikes (P = 0.016 and P = 0.006, respectively). We found qualitatively consistent results using a fully automated spike ripple detector, including comparison with an automated spike detector. We conclude that scalp spike ripple events identify disease and track with seizure risk in this epilepsy population, using both semi-automated and fully automated detection methods, and that this biomarker outperforms analysis of spikes alone in categorizing seizure risk. These data provide evidence that spike ripples are a specific non-invasive biomarker for seizure risk in benign epilepsy with centrotemporal spikes and support future work to evaluate the utility of this biomarker to guide medication trials and tapers in these children and predict seizure risk in other at-risk populations.
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Vemuru, Krishnamurthy V. "Implementation of the Canny Edge Detector Using a Spiking Neural Network". Future Internet 14, n.º 12 (11 de diciembre de 2022): 371. http://dx.doi.org/10.3390/fi14120371.

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Edge detectors are widely used in computer vision applications to locate sharp intensity changes and find object boundaries in an image. The Canny edge detector is the most popular edge detector, and it uses a multi-step process, including the first step of noise reduction using a Gaussian kernel and a final step to remove the weak edges by the hysteresis threshold. In this work, a spike-based computing algorithm is presented as a neuromorphic analogue of the Canny edge detector, where the five steps of the conventional algorithm are processed using spikes. A spiking neural network layer consisting of a simplified version of a conductance-based Hodgkin–Huxley neuron as a building block is used to calculate the gradients. The effectiveness of the spiking neural-network-based algorithm is demonstrated on a variety of images, showing its successful adaptation of the principle of the Canny edge detector. These results demonstrate that the proposed algorithm performs as a complete spike domain implementation of the Canny edge detector.
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Zhang, Dongmao, Karim N. Jallad y Dor Ben-Amotz. "Stripping of Cosmic Spike Spectral Artifacts Using a New Upper-Bound Spectrum Algorithm". Applied Spectroscopy 55, n.º 11 (noviembre de 2001): 1523–31. http://dx.doi.org/10.1366/0003702011953757.

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A new upper-bound spectrum (UBS) method for removal of cosmic spike artifacts from spectra or images collected using a charge-coupled device (CCD) detector is proposed. This algorithm, which is shown to outperform previous methods, relies on an upper-bound spectrum, derived from scaled copies of consecutively collected spectra, which serves as a threshold for the detection of suspected cosmic spikes. Detected spikes are removed by replacement with the corresponding points in other spectra. Thus, unlike other commonly used methods, the UBS algorithm requires no smoothing or noise filtering and more reliably removes cosmic spikes of all magnitudes while introducing far less (if any) spectral distortion. The UBS method is tested using both synthetic and experimental (gypsum and gypsum/hematite mixture) spectra containing variable background (fluorescence), noise, and cosmic spike interference. The UBS method may in rare instances mistakenly identify spectral noise or photo-induced changes in band intensity (or shape) as cosmic spikes. However, as demonstrated through the use of both synthetic and experimental examples, such misidentifications produce little or no spectral distortion or artifacts in the resulting cosmic-spike-free output spectra.
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Zhao, Jianqing, Xiaohu Zhang, Jiawei Yan, Xiaolei Qiu, Xia Yao, Yongchao Tian, Yan Zhu y Weixing Cao. "A Wheat Spike Detection Method in UAV Images Based on Improved YOLOv5". Remote Sensing 13, n.º 16 (5 de agosto de 2021): 3095. http://dx.doi.org/10.3390/rs13163095.

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Deep-learning-based object detection algorithms have significantly improved the performance of wheat spike detection. However, UAV images crowned with small-sized, highly dense, and overlapping spikes cause the accuracy to decrease for detection. This paper proposes an improved YOLOv5 (You Look Only Once)-based method to detect wheat spikes accurately in UAV images and solve spike error detection and miss detection caused by occlusion conditions. The proposed method introduces data cleaning and data augmentation to improve the generalization ability of the detection network. The network is rebuilt by adding a microscale detection layer, setting prior anchor boxes, and adapting the confidence loss function of the detection layer based on the IoU (Intersection over Union). These refinements improve the feature extraction for small-sized wheat spikes and lead to better detection accuracy. With the confidence weights, the detection boxes in multiresolution images are fused to increase the accuracy under occlusion conditions. The result shows that the proposed method is better than the existing object detection algorithms, such as Faster RCNN, Single Shot MultiBox Detector (SSD), RetinaNet, and standard YOLOv5. The average accuracy (AP) of wheat spike detection in UAV images is 94.1%, which is 10.8% higher than the standard YOLOv5. Thus, the proposed method is a practical way to handle the spike detection in complex field scenarios and provide technical references for field-level wheat phenotype monitoring.
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Arai, Itaru, Yoshiyuki Yamada, Tomomitsu Asaka y Masao Tachibana. "Light-Evoked Oscillatory Discharges in Retinal Ganglion Cells Are Generated by Rhythmic Synaptic Inputs". Journal of Neurophysiology 92, n.º 2 (agosto de 2004): 715–25. http://dx.doi.org/10.1152/jn.00159.2004.

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In the visual system, optimal light stimulation sometimes generates γ-range (ca. 20 ∼ 80 Hz) synchronous oscillatory spike discharges. This phenomenon is assumed to be related to perceptual integration. Applying a planar multi-electrode array to the isolated frog retina, Ishikane et al. demonstrated that dimming detectors, off-sustained type ganglion cells, generate synchronous oscillatory spike discharges in response to diffuse dimming illumination. In the present study, applying the whole cell current-clamp technique to the isolated frog retina, we examined how light-evoked oscillatory spike discharges were generated in dimming detectors. Light-evoked oscillatory (∼30 Hz) spike discharges were triggered by rhythmic (∼30 Hz) fluctuations superimposed on a depolarizing plateau potential. When a suprathreshold steady depolarizing current was injected into a dimming detector, only a few spikes were evoked at the stimulus onset. However, repetitive spikes were triggered by a γ-range sinusoidal current superimposed on the steady depolarizing current. Thus the light-evoked rhythmic fluctuations are likely to be generated presynaptically. The light-evoked rhythmic fluctuations were suppressed not by intracellular application of N-(2,6-dimethyl-phenylcarbamoylmethyl)triethylammonium bromide (QX-314), a Na+ channel blocker, to the whole cell clamped dimming detector but by bath-application of tetrodotoxin to the retina. The light-evoked rhythmic fluctuations were suppressed by a GABAA receptor antagonist but potentiated by a GABAC receptor antagonist, whereas these fluctuations were little affected by a glycine receptor antagonist. Because amacrine cells are spiking neurons and because GABA is one of the main transmitters released from amacrine cells, amacrine cells may participate in generating rhythmically fluctuated synaptic input to dimming detectors.
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Vallicelli, Elia, Marco Reato, Marta Maschietto, Stefano Vassanelli, Daniele Guarrera, Federico Rocchi, Gianmaria Collazuol, Ralf Zeitler, Andrea Baschirotto y Marcello De Matteis. "Neural Spike Digital Detector on FPGA". Electronics 7, n.º 12 (5 de diciembre de 2018): 392. http://dx.doi.org/10.3390/electronics7120392.

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This paper presents a multidisciplinary experiment where a population of neurons, dissociated from rat hippocampi, has been cultivated over a CMOS-based micro-electrode array (MEA) and its electrical activity has been detected and mapped by an advanced spike-sorting algorithm implemented on FPGA. MEAs are characterized by low signal-to-noise ratios caused by both the contactless sensing of weak extracellular voltages and the high noise power coming from cells and analog electronics signal processing. This low SNR forces to utilize advanced noise rejection algorithms to separate relevant neural activity from noise, which are usually implemented via software/off-line. However, off-line detection of neural spikes cannot be obviously used for real-time electrical stimulation. In this scenario, this paper presents a proper FPGA-based system capable to detect in real-time neural spikes from background noise. The output signals of the proposed system provide real-time spatial and temporal information about the culture electrical activity and the noise power distribution with a minimum latency of 165 ns. The output bit-stream can be further utilized to detect synchronous activity within the neural network.
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Lüdtke, Niklas y Mark E. Nelson. "Short-Term Synaptic Plasticity Can Enhance Weak Signal Detectability in Nonrenewal Spike Trains". Neural Computation 18, n.º 12 (diciembre de 2006): 2879–916. http://dx.doi.org/10.1162/neco.2006.18.12.2879.

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We study the encoding of weak signals in spike trains with interspike interval (ISI) correlations and the signals' subsequent detection in sensory neurons. Motivated by the observation of negative ISI correlations in auditory and electrosensory afferents, we assess the theoretical performance limits of an individual detector neuron receiving a weak signal distributed across multiple afferent inputs. We assess the functional role of ISI correlations in the detection process using statistical detection theory and derive two sequential likelihood ratio detector models: one for afferents with renewal statistics; the other for afferents with negatively correlated ISIs. We suggest a mechanism that might enable sensory neurons to implicitly compute conditional probabilities of presynaptic spikes by means of short-term synaptic plasticity. We demonstrate how this mechanism can enhance a postsynaptic neuron's sensitivity to weak signals by exploiting the correlation structure of the input spike trains. Our model not only captures fundamental aspects of early electrosensory signal processing in weakly electric fish, but may also bear relevance to the mammalian auditory system and other sensory modalities.
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Kreuz, Thomas, Mario Mulansky y Nebojsa Bozanic. "SPIKY: a graphical user interface for monitoring spike train synchrony". Journal of Neurophysiology 113, n.º 9 (mayo de 2015): 3432–45. http://dx.doi.org/10.1152/jn.00848.2014.

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Techniques for recording large-scale neuronal spiking activity are developing very fast. This leads to an increasing demand for algorithms capable of analyzing large amounts of experimental spike train data. One of the most crucial and demanding tasks is the identification of similarity patterns with a very high temporal resolution and across different spatial scales. To address this task, in recent years three time-resolved measures of spike train synchrony have been proposed, the ISI-distance, the SPIKE-distance, and event synchronization. The Matlab source codes for calculating and visualizing these measures have been made publicly available. However, due to the many different possible representations of the results the use of these codes is rather complicated and their application requires some basic knowledge of Matlab. Thus it became desirable to provide a more user-friendly and interactive interface. Here we address this need and present SPIKY, a graphical user interface that facilitates the application of time-resolved measures of spike train synchrony to both simulated and real data. SPIKY includes implementations of the ISI-distance, the SPIKE-distance, and the SPIKE-synchronization (an improved and simplified extension of event synchronization) that have been optimized with respect to computation speed and memory demand. It also comprises a spike train generator and an event detector that makes it capable of analyzing continuous data. Finally, the SPIKY package includes additional complementary programs aimed at the analysis of large numbers of datasets and the estimation of significance levels.
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Ware, George M. "Method Validation Study of Hypoglycin A Determination in Ackee Fruit". Journal of AOAC INTERNATIONAL 85, n.º 4 (1 de julio de 2002): 933–37. http://dx.doi.org/10.1093/jaoac/85.4.933.

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Abstract A study was conducted to validate the performance characteristics of a published method entitled “Reversed-Phase Liquid Chromatographic Detection of Hypoglycin A in Canned Ackee Fruit Sample.” Hypoglycin A (HG-A) was extracted from ackee fruit with 80% ethanol–water, centrifuged, and filtered; the sample extract then was reacted with phenylisothiocyanate. HG-A was separated by reversed-phase chromatography as the phenylthiocarbamyl derivative and detected at the low nanogram level using a UV detector at 254 nm. A study was conducted to determine recovery of HG-A added to a control ackee fruit sample. A control sample containing a low level of HG-A was spiked with 403.2, 201.6, 96.8, and 48.4 μg HG-A/g ackee fruit, respectively. Twelve replicates were analyzed for each spike level. The mean percent recovery ± standard deviation for spike levels 403.2, 201.6, 96.8, and 48.4 μg HG-A/g were 94.37 ± 1.27, 99.12 ± 2.09, 107.95 ± 5.42, and 129.18 ± 15.32%, respectively. The percent coefficient of variation (%CV) for spike levels 403.2, 201.6, 96.8, and 48.4 μg HG-A/g were 1.35, 2.11, 5.02, and 11.86%, respectively. The recovery data indicate that HG-A can be recovered from ackee fruit with excellent accuracy and precision. Precision data obtained from replicate assays of ackee fruit naturally contaminated with low, medium, and high HG-A levels is presented.
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Barker, Peter D. R. "Sensitization and multiplicative noise in the descending contralateral movement detector (DCMD) of the locust". Visual Neuroscience 10, n.º 5 (septiembre de 1993): 791–809. http://dx.doi.org/10.1017/s0952523800006040.

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AbstractSpike discharges from the descending contralateral movement detector (DCMD) were recorded extracellularly from the ventral nerve cord of the locust in complete darkness, in response to dim flashes of constant-intensity light, and in response to pairs of identical flashes presented different intervals apart. Three phenomena were discovered: novel long-term sensitization which changes the DCMD's sensitivity to light, a multiplicative cascade process driven by shot events, and the suppression of the spike discharge shortly after a dim flash.The DCMD's spike discharge is stochastic. It can be considered as a two-stage cascade process producing intrinsic multiplicative noise. An effective photon, or thermal isomerization in complete darkness, produces an unseen shot event which in turn initiates a random number of DCMD spikes in a cluster. A shot initiates a variable number of spikes when it directs the rate of a Poisson process. The results of statistical analyses are consistent with this model when the amplitudes of shot events are variable. The transmission efficiency is low because at least 2.4–9.6 quantum bumps are required to produce one extra DCMD spike.The DCMD has a constant mean discharge rate of 0.25–1.5 spikes/s in complete darkness. Clustering about particular points in time (shots) leads to a lack of independence between interspike intervals, and the overdispersion of interspike interval and number distributions compared with those from a simple Poisson process. The mean cluster size is 1.3–1.6 spikes in darkness. Similar clustering was found in response to flashes of light.A dim flash changes the DCMD's sensitivity to light, even at threshold when no spike discharge results. Sensitization occurs because the average number of shot events produced by isoquantal flashes depends on the history of visual stimulation. This contributes to the nonlinear response-intensity function. The evolution of sensitization is roughly constant in different DCMD cells, lasting approximately 3 s after a flash. Sensitization was observed in response to light only, presumably because the intensity of dark-light is too low. It is proposed that sensitization is associated with a set of processes or molecular state in the presynaptic region of a chemical synapse.
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Tesis sobre el tema "Spike detector"

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Ervin, Brian. "Neural Spike Detection and Classification Using Massively Parallel Graphics Processing". University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1377868773.

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Carey, Howard J. III. "EEG Interictal Spike Detection Using Artificial Neural Networks". VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4648.

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Epilepsy is a neurological disease causing seizures in its victims and affects approximately 50 million people worldwide. Successful treatment is dependent upon correct identification of the origin of the seizures within the brain. To achieve this, electroencephalograms (EEGs) are used to measure a patient’s brainwaves. This EEG data must be manually analyzed to identify interictal spikes that emanate from the afflicted region of the brain. This process can take a neurologist more than a week and a half per patient. This thesis presents a method to extract and process the interictal spikes in a patient, and use them to reduce the amount of data for a neurologist to manually analyze. The effectiveness of multiple neural network implementations is compared, and a data reduction of 3-4 orders of magnitude, or upwards of 99%, is achieved.
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Malvestio, Irene. "Detection of directional interactions between neurons from spike trains". Doctoral thesis, Universitat Pompeu Fabra, 2019. http://hdl.handle.net/10803/666226.

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An important problem in neuroscience is the assessment of the connectivity between neurons from their spike trains. One recent approach developed for the detection of directional couplings between dynamics based on recorded point processes is the nonlinear interdependence measure L. In this thesis we first use the Hindmarsh-Rose model system to test L in the presence of noise and for different spiking regimes of the dynamics. We then compare the performance of L against the linear cross-correlogram and two spike train distances. Finally, we apply all measures to neuronal spiking data from an intracranial whole-night recording of a patient with epilepsy. When applied to simulated data, L proves to be versatile, robust and more sensitive than the linear measures. Instead, in the real data the linear measures find more connections than L, in particular for neurons in the same brain region and during slow wave sleep.
Un problema important en la neurociència és determinar la connexió entre neurones utilitzant dades dels seus trens d’impulsos. Un mètode recent que afronta la detecció de connexions direccionals entre dinàmiques utilitzant processos puntuals és la mesura d’interdependència no lineal L. En aquesta tesi, utilitzem el model de Hindmarsh-Rose per testejar L en presència de soroll i per diferents règims dinàmics. Després comparem el desempenyorament de L en comparació al correlograma lineal i a dues mesures de trens d’impulsos. Finalment, apliquem totes aquestes mesures a dades d’impulsos de neurones obtingudes de senyals intracranials electroencefalogràfiques gravades durant una nit a un pacient amb epilèpsia. Quan utilitzem dades simulades, L demostra que és versàtil, robusta i més sensible que les mesures lineals. En canvi, utilitzant dades reals, les mesures lineals troben més connexions que L, especialment entre neurones en la mateixa àrea del cervell i durant la fase de son d’ones lentes.
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4

Guo, Bin. "A bio-inspired electronic nose micro-system based on integrated gas sensor array and log-spike processing /". View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20GUO.

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Chen, Hung Tat. "A portable electronic nose micro-system based on bio-inspired log-spike processing /". View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?ECED%202009%20CHEN.

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Armstrong, Brian Clement. "Processing techniques for improved radar detection in spiky clutter". Thesis, University College London (University of London), 1992. http://discovery.ucl.ac.uk/1317536/.

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The problem of improved radar detection of targets embedded in spiky clutter is addressed. Two main areas where improvements may be possible are investigated, namely improved clutter suppression by doppler filtering, and improved Constant False Alarm Rate (CFAR) processing. The clutter suppression performance of several doppler processors is quantified under a wide range of conditions. It is shown that in spatially homogeneous clutter ideal optimal (Hsiao) filters offer 2 to 3 dB higher improvement factor than conventional techniques. Adaptive Hsiao filters are evaluated under conditions of spatially heterogeneous clutter, and it is shown that practical losses due to filter adaptivity and spectral heterogeneity will outweigh the superior performance of ideal Hsiao filters in homogeneous clutter. It is concluded that improved doppler filtering offers little scope for improving detection performance in spiky clutter, and that more significant benefits are to be gained through improved CFAR processing. The performance of three current generation CFAR processors is evaluated in spatially uncorrelated K-distributed clutter to quantify detection losses. It is shown that losses of in excess of 10 dB can be expected in spiky clutter. Reducing the loss by exploitation of any spatial correlation of the underlying clutter power is investigated. To this end a mathematically rigorous model for spatially correlated K-distributed clutter is derived. An improved CFAR processor based on optimal weighting of reference cells is formulated and evaluated. It is shown that in highly correlated clutter CFAR loss can be reduced by 2 to 5 dB compared to Cell Averaging CFAR processors. An alternative "RDT-CFAR" processor is formulated to eliminate reliance on spatial correlation, and this is shown to reduce CFAR loss by more than 10 dB in spectrally homogeneous spiky clutter. However, an increase in false alarm rate in clutter without constant spectrum is demonstrated. The RDT-CFAR processor has been modified to eliminate dependence on surrounding range bins. The resulting "δ-CFAR" processor reduces CFAR loss by more than 10 dB in even moderately spiky clutter. It is also immune to extraneous targets and clutter edges, and its false alarm performance is insensitive to clutter spikiness.
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Shallwani, Aziz. "An adaptive playout algorithm with delay spike detection for real-time VoIP /". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80143.

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As the Internet is a best-effort delivery network, audio packets may be delayed or lost en route to the receiver due to network congestion. To compensate for the variation in network delay, audio applications buffer received packets before playing them out. Basic algorithms adjust the packet playout time during periods of silence such that all packets within a talkspurt are equally delayed. Another approach is to scale individual voice packets using a dynamic time-scale modification technique based on the WSOLA algorithm.
In this work, an adaptive playout algorithm based on the normalized least mean square algorithm, is improved by introducing a spike-detection mode to rapidly adjust to delay spikes. Simulations on Internet traces show that the enhanced bi-modal playout algorithm improves performance by reducing both the average delay and the loss rate as compared to the original algorithm.
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Enatsu, Rei. "Usefulness of MEG magnetometer for spike detection in patients with mesial temporal epileptic focus". Kyoto University, 2008. http://hdl.handle.net/2433/124240.

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Elaraby, Nashwa. "ARCHITECTURE DESIGN FOR A NEURAL SPIKE-BASED DATA REDUCTION PLATFORM PROCESSING THOUSANDS OF RECORDING CHANNELS". Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/259825.

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Electrical Engineering
Ph.D.
Simultaneous recordings of single and multi-unit neural signals from multiple cortical areas in the brain are a vital tool for gaining more understanding of the operating mechanism of the brain as well as for developing Brain Machine Interfaces. Monitoring the activity levels of hundreds or even thousands of neurons can lead to reliable decoding of brain signals for controlling prosthesis of multiple degrees of freedom and different functionalities. With the advancement of high density microelectrode arrays, the craving of neuroscience research to record the activity of thousands of neurons is achievable. Recently CMOS-based Micro-electrode Arrays MEAs featuring high spatial and temporal resolution have been reported. The augmentation in the number of recording sites carries different challenges to the neural signal processing system. The primary challenge is the massive increase in the incoming data that needs to be transmitted and processed in real time. Data reduction based on the sparse nature of the neural signals with respect to time becomes essential. The dissertation presents the design of a neural spike-based data reduction platform that can handle a few thousands of channels on Field Programmable Gate Arrays (FPGAs), making use of their massive parallel processing capabilities and reconfigurability. For Standalone implementation the spike detector core uses Finite State Machines (FSMs) to control the interface with the data acquisition as well as sending the spike waveforms to a common output FIFO. The designed neural signal processing platform integrates the application of high-speed serial Multi-Gigabit transceivers on FPGAs to allow massive data transmission in real time. It also provides a design for autonomous threshold setting for each channel.
Temple University--Theses
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Scandellari, Carolina. "Algortimi di spike detection per applicazioni neuroprotesiche: sviluppo di modelli, implementazione e valutazione delle performance". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19904/.

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I disordini neurologici costituiscono il 6,3% delle cause di malattia in tutto il mondo, diventando una delle priorità della sanità globale. Per trattare questi disordini si utilizzano farmaci, ma alcuni pazienti possono risultarne resistenti. La Neuroingegneria propone soluzioni innovative per la cura e la riabilitazione di queste patologie, proponendo, tra le varie soluzioni, le neuroprotesi, capaci di sostituire un’area danneggiata del cervello o di ricollegare artificialmente due aree disconnesse bypassando la lesione che ha causato il danno. Tra questi, il dispositivo sviluppato presso la University of Kansas (KUMC) si è dimostrato essere efficace in esperimenti effettuati su topi con lesione focale in area motoria. Il funzionamento di questo dispositivo è basato sull’impianto di micro-elettrodi in due regioni cerebrali disconnesse a causa di una lesione. Questi creano un ponte in grado di ricollegare le due aree scollegate attraverso la registrazione di eventi (spike) in una delle due aree, e la seguente somministrazione di corrente nella seconda. In questo tipo di dispositivi, è importantissimo effettuare una identificazione corretta degli spikes. Il mio lavoro di tesi si inserisce nell’ambito della collaborazione tra il Rehab Technologies Lab (IIT, Genova), dove ho svolto il tirocinio, e la KUMC in relazione al progetto per lo sviluppo di neuroprotesi innovative per il recupero motorio a seguito di danni cerebrali. Nello specifico, il mio lavoro di Tesi si concentra sulla Spike Detection (SD), di cui uno dei problemi fondamentali è la mancanza di un ground truth, ovvero di una conoscenza a priori della localizzazione degli spikes nel tracciato. Nel contesto descritto sopra, si inseriscono gli obiettivi di questa Tesi: fornire un ground truth, studiare e adattare un set di algoritmi di SD già presenti in letteratura, modificare un algoritmo ad alte prestazioni sviluppato all’interno di IIT in passato e confrontare le prestazioni di tutti gli algoritmi di SD.
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Libros sobre el tema "Spike detector"

1

Fan, Zhang, Otis Brian y SpringerLink (Online service), eds. Ultra Low-Power Integrated Circuit Design for Wireless Neural Interfaces. New York, NY: Springer Science+Business Media, LLC, 2011.

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K, Minnifield Nona, Society of Photo-optical Instrumentation Engineers. y United States. National Aeronautics and Space Administration. Technology Transfer/Commercialization Offices., eds. NASA/SPIE Conference on Spin-off Technologies from NASA for Commercial Sensors and Scientific Applications: 25-26 July 1994, San Diego, California. Bellingham, Wash: The Society, 1994.

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SPSE's International Symposium and Exposition on Electronic Imaging Devices and Systems '88 (1988 Los Angeles, Calif.). Three-dimensional imaging and remote sensing imaging: Part of SPSE's International Symposium and Exposition on Electronic Imaging Devices and Systems '88 : sponsored by SPIE - the International Society for Optical Engineering, 14-15 January 1988, Los Angeles, California. Editado por Robbins Woodrow E, Society of Photographic Scientists and Engineers. y Society of Photo-optical Instrumentation Engineers. Bellingham, Wash: SPIE - The International Society for Optical Engineering, 1988.

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Otis, Brian, Fan Zhang y Jeremy Holleman. Ultra Low-Power Integrated Circuit Design for Wireless Neural Interfaces. Springer New York, 2014.

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Photonic Sensing Technologies (Proceedings of SPIE). Society of Photo Optical, 2006.

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Masten, michael K. y Larry A. Stockum. Acquisition, Tracking, And Pointing 19 (Proceedings of SPIE). Society of Photo Optical, 2005.

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Future Infrared Detector Materials (Spie Proceedings, Vol 1106). SPIE-International Society for Optical Engine, 1989.

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Park, Seung-Hun. A knowledge-based approach to abnormal EEG spike detection. 1990.

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Scheggi, Annamaria V. Chemical, Biochemical, and Environmental Fiber Sensors VII: 19-20 June 1995 Munich, Frg (Spie Proceedings, Vol 2508) (Spie Proceedings, Vol 2508). SPIE--The International Society for Optical Engineering, 1995.

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(Editor), Tuan Vo-Dinh, Robert A. Lieberman (Editor) y Gunter Gauglitz (Editor), eds. Advanced Environmental, Chemical and Biological Sensing Technologies 3 (SPIE Conference Proceedings). SPIE-International Society for Optical Engine, 2005.

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Capítulos de libros sobre el tema "Spike detector"

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Tapani, Karoliina T., Sampsa Vanhatalo y Nathan J. Stevenson. "Incorporating spike correlations into an SVM-based neonatal seizure detector". En EMBEC & NBC 2017, 322–25. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5122-7_81.

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Holleman, Jeremy, Fan Zhang y Brian Otis. "Spike Detection and Characterization". En Ultra Low-Power Integrated Circuit Design for Wireless Neural Interfaces, 51–63. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-6727-5_7.

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Divakaran, Dinil Mon, Eitan Altman y Pascale Vicat-Blanc Primet. "Size-Based Flow-Scheduling Using Spike-Detection". En Analytical and Stochastic Modeling Techniques and Applications, 331–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21713-5_24.

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Sarje, A. y P. Abshire. "Spike Detection for Integrated Circuits: Comparative Study". En IFMBE Proceedings, 282–85. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14998-6_72.

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Waykule, Jyoti M. y V. R. Udupi. "Spine Diseases Detection Using SVM". En Techno-Societal 2020, 309–19. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-69921-5_31.

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Martel, Arthur. "Spike Detection Using Advanced Analytics and Data Analysis". En The Minerals, Metals & Materials Series, 485–90. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72284-9_64.

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Braune, Christian, Christian Borgelt y Sonja Grün. "Assembly Detection in Continuous Neural Spike Train Data". En Advances in Intelligent Data Analysis XI, 78–89. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-34156-4_9.

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Focosi, Daniele. "Spike Protein Mutations Detected in Currently Circulating Strains". En SpringerBriefs in Microbiology, 27–54. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-87324-0_5.

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Tiganj, Zoran y Mamadou Mboup. "Spike Detection and Sorting: Combining Algebraic Differentiations with ICA". En Independent Component Analysis and Signal Separation, 475–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00599-2_60.

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Lu, Hu, Zhe Liu y Yuqing Song. "Evolutionary Clustering Detection of Similarity in Neuronal Spike Patterns". En Advances in Neural Networks – ISNN 2014, 558–67. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-12436-0_62.

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Actas de conferencias sobre el tema "Spike detector"

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Lee, Moon-Ho y Seong-Ho Bae. "Spike-like noises of pyroelectric thermal detector". En Symposium on Integrated Optoelectronics, editado por Gail J. Brown y Manijeh Razeghi. SPIE, 2000. http://dx.doi.org/10.1117/12.382139.

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Lin, True L., Jin S. Park, Sarath D. Gunapala, Eric W. Jones y Hector M. Del Castillo. "Long-wavelength infrared doping-spike PtSi detector". En SPIE's 1993 International Symposium on Optics, Imaging, and Instrumentation, editado por Bjorn F. Andresen y Freeman D. Shepherd. SPIE, 1993. http://dx.doi.org/10.1117/12.160558.

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Horak, Peter C., Stephen Meisenhelter, Markus E. Testorf, Andrew C. Connolly, Kathryn A. Davis y Barbara C. Jobst. "Implementation and evaluation of an interictal spike detector". En SPIE Optical Engineering + Applications, editado por Philip J. Bones, Michael A. Fiddy y Rick P. Millane. SPIE, 2015. http://dx.doi.org/10.1117/12.2189248.

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Gagnon-Turcotte, G., Y. LeChasseur, C. Bories, Y. De Koninck y B. Gosselin. "An optimized adaptive spike detector for behavioural experiments". En 2016 IEEE International Symposium on Circuits and Systems (ISCAS). IEEE, 2016. http://dx.doi.org/10.1109/iscas.2016.7527436.

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Peng, Chung-Ching, Pawan Sabharwal y Rizwan Bashirullah. "An adaptive neural spike detector with threshold-lock loop". En 2009 IEEE International Symposium on Circuits and Systems - ISCAS 2009. IEEE, 2009. http://dx.doi.org/10.1109/iscas.2009.5118217.

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Raja, K., S. Saravanan, P. Malini, V. Raveena y R. Sai Praveena. "Design of a spike detector for fully Integrated Neuromodulation SoC". En 2017 11th International Conference on Intelligent Systems and Control (ISCO). IEEE, 2017. http://dx.doi.org/10.1109/isco.2017.7856013.

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Jalalifar, Majid y Gyung-Su Byun. "An ultra-low power spike detector for implantable biomedical systems". En 2013 IEEE 14th Annual Wireless and Microwave Technology Conference (WAMICON). IEEE, 2013. http://dx.doi.org/10.1109/wamicon.2013.6572752.

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Gagnon-Turcotte, G., M. Sawan y B. Gosselin. "Low-power adaptive spike detector based on a sigma-delta control loop". En 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2015. http://dx.doi.org/10.1109/embc.2015.7318819.

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Guo, Xiaorang, MohammadAli Shaeri y Mahsa Shoaran. "An Accurate and Hardware-Efficient Dual Spike Detector for Implantable Neural Interfaces". En 2022 IEEE Biomedical Circuits and Systems Conference (BioCAS). IEEE, 2022. http://dx.doi.org/10.1109/biocas54905.2022.9948602.

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Saggese, Gerardo, Efstratios Zacharelos y Antonio Giuseppe Maria Strollo. "Low Power Spike Detector for Brain-Silicon Interface using Differential Amplitude Slope Operator". En 2022 17th Conference on Ph.D Research in Microelectronics and Electronics (PRIME). IEEE, 2022. http://dx.doi.org/10.1109/prime55000.2022.9816758.

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Informes sobre el tema "Spike detector"

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Perkins, Dustin. Invasive exotic plant monitoring at Golden Spike National Historical Park: 2021 field season. Editado por Alice Wondrak Biel. National Park Service, junio de 2022. http://dx.doi.org/10.36967/2293843.

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Invasive exotic plant (IEP) species are one of the biggest threats to natural ecosystem integrity and biodiversity. Controlling them is a high priority for the National Park Service. The Northern Colorado Plateau Network (NCPN) selected the early detection of IEPs as one of 11 monitoring protocols to be implemented as part of its long-term monitoring program. This report represents work completed during the 2021 field season at Golden Spike National Historical Park (NHP). On June 24–25, 2021, we recorded a total of six priority IEP species during monitoring at the park. A total of 191 priority IEP patches were detected along 20 kilometers (12.4 miles) of 13 monitoring routes that covered all major roads, trails, and riparian areas. Three additional IEP species were recorded only in transects. The highest densities of IEP patches were recorded along the Hydro 1 and Last Cut drainages, followed by the Residence Service Road, East Tour Road, and Visitor Center Sidewalk Area. Rush skeletonweed (Chondrilla juncea) was the most prevalent priority species, representing 46% of all recorded patches. Field bindweed (Convolvulus arvensis) and Scotch thistle (Onopordum acanthium) constituted most other patches. The notable absence of Russian knapweed (Centaurea repens) represents past control efforts for this species. When compared to 2018, there was a dramatic increase in the number of IEP patches in 2021, driven by rush skeletonweed and field bindweed. More-widespread species monitored in transects were still common, with cheatgrass (Bromus tectorum), crested wheatgrass (Agropyron cristatum), and tumble mustard (Sisymbrium altissimum) present in 84%, 45%, and 36% of all transects, respectively. The network plans to return to Golden Spike NHP for an eighth year of monitoring in 2023.
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George, John S. Neuromimetic Computing Systems for Visual Object Detection and SpatioTemporal Inference: Toward Spike-based Computation. Office of Scientific and Technical Information (OSTI), mayo de 2013. http://dx.doi.org/10.2172/1078361.

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Irudayaraj, Joseph, Ze'ev Schmilovitch, Amos Mizrach, Giora Kritzman y Chitrita DebRoy. Rapid detection of food borne pathogens and non-pathogens in fresh produce using FT-IRS and raman spectroscopy. United States Department of Agriculture, octubre de 2004. http://dx.doi.org/10.32747/2004.7587221.bard.

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Rapid detection of pathogens and hazardous elements in fresh fruits and vegetables after harvest requires the use of advanced sensor technology at each step in the farm-to-consumer or farm-to-processing sequence. Fourier-transform infrared (FTIR) spectroscopy and the complementary Raman spectroscopy, an advanced optical technique based on light scattering will be investigated for rapid and on-site assessment of produce safety. Paving the way toward the development of this innovative methodology, specific original objectives were to (1) identify and distinguish different serotypes of Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Bacillus cereus by FTIR and Raman spectroscopy, (2) develop spectroscopic fingerprint patterns and detection methodology for fungi such as Aspergillus, Rhizopus, Fusarium, and Penicillium (3) to validate a universal spectroscopic procedure to detect foodborne pathogens and non-pathogens in food systems. The original objectives proposed were very ambitious hence modifications were necessary to fit with the funding. Elaborate experiments were conducted for sensitivity, additionally, testing a wide range of pathogens (more than selected list proposed) was also necessary to demonstrate the robustness of the instruments, most crucially, algorithms for differentiating a specific organism of interest in mixed cultures was conceptualized and validated, and finally neural network and chemometric models were tested on a variety of applications. Food systems tested were apple juice and buffer systems. Pathogens tested include Enterococcus faecium, Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus, Yersinia enterocolitis, Shigella boydii, Staphylococus aureus, Serratiamarcescens, Pseudomonas vulgaris, Vibrio cholerae, Hafniaalvei, Enterobacter cloacae, Enterobacter aerogenes, E. coli (O103, O55, O121, O30 and O26), Aspergillus niger (NRRL 326) and Fusarium verticilliodes (NRRL 13586), Saccharomyces cerevisiae (ATCC 24859), Lactobacillus casei (ATCC 11443), Erwinia carotovora pv. carotovora and Clavibacter michiganense. Sensitivity of the FTIR detection was 103CFU/ml and a clear differentiation was obtained between the different organisms both at the species as well as at the strain level for the tested pathogens. A very crucial step in the direction of analyzing mixed cultures was taken. The vector based algorithm was able to identify a target pathogen of interest in a mixture of up to three organisms. Efforts will be made to extend this to 10-12 key pathogens. The experience gained was very helpful in laying the foundations for extracting the true fingerprint of a specific pathogen irrespective of the background substrate. This is very crucial especially when experimenting with solid samples as well as complex food matrices. Spectroscopic techniques, especially FTIR and Raman methods are being pursued by agencies such as DARPA and Department of Defense to combat homeland security. Through the BARD US-3296-02 feasibility grant, the foundations for detection, sample handling, and the needed algorithms and models were developed. Successive efforts will be made in transferring the methodology to fruit surfaces and to other complex food matrices which can be accomplished with creative sampling methods and experimentation. Even a marginal success in this direction will result in a very significant breakthrough because FTIR and Raman methods, in spite of their limitations are still one of most rapid and nondestructive methods available. Continued interest and efforts in improving the components as well as the refinement of the procedures is bound to result in a significant breakthrough in sensor technology for food safety and biosecurity.
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Hochman, Ayala, Thomas Nash III y Pamela Padgett. Physiological and Biochemical Characterization of the Effects of Oxidant Air Pollutants, Ozone and Gas-phase Nitric Acid, on Plants and Lichens for their Use as Early Warning Biomonitors of these Air Pollutants. United States Department of Agriculture, enero de 2011. http://dx.doi.org/10.32747/2011.7697115.bard.

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Introduction. Ozone and related oxidants are regarded as the most important phytotoxic air pollutant in many parts of the western world. A previously unrecognized component of smog, nitric acid, may have even greater deleterious effects on plants either by itself or by augmenting ozone injury. The effects of ozone on plants are well characterized with respect to structural and physiological changes, but very little is known about the biochemical changes in plants and lichens exposed to ozone and/or HNO3. Objectives.To compare and contrast the responses of crop plants and lichens to dry deposition of HNO3 and O3., separately, and combined in order to assess our working hypothesis that lichens respond to air pollution faster than plants. Lichens are most suitable for use as biomonitors because they offer a live-organism-based system that does not require maintenance and can be attached to any site, without the need for man-made technical support systems. Original Immediate aims To expose the tobacco (Nicotiana tabacum L.) cultivar Bel-W3 that is ozone supersensitive and the ozone sensitive red kidney bean (Phaseolusvulgaris) and the lichen Ramalinamenziesii to controlled HNO3 and O3 fumigations and combined and to follow the resulting structural, physiological and biochemical changes, with special reference to reactive oxygen species related parameters. Revised. Due to technical problems and time limitations we studied the lichen Ramalinamenziesii and two cultivar of tobacco: Bel-W3 that is ozone supersensitive and a resistant cultivar, which were exposed to HNO3 and O3 alone (not combined). Methodology. Plants and lichens were exposed in fumigation experiments to HNO3 and O3, in constantly stirred tank reactors and the resulting structural, physiological and biochemical changes were analyzed. Results. Lichens. Exposure of Ramalinamenziesiito HNO3 resulted in cell membrane damage that was evident by 14 days and continues to worsen by 28 days. Chlorophyll, photosynthesis and respiration all declined significantly in HNO3 treatments, with the toxic effects increasing with dosage. In contrast, O3 fumigations of R. menziesii showed no significant negative effects with no differences in the above response variables between high, moderate and low levels of fumigations. There was a gradual decrease in catalase activity with increased levels of HNO3. The activity of glutathione reductase dropped to 20% in thalli exposed to low HNO3 but increased with its increase. Glucose 6-phosphate dehydrogenase activity increase by 20% with low levels of the pollutants but decreased with its increase. Tobacco. After 3 weeks of exposure of the sensitive tobacco cultivar to ozone there were visible symptoms of toxicity, but no danmage was evident in the tolerant cultivar. Neither cultivar showed any visible symptoms after exposure to HNO3.In tobacco fumigated with O3, there was a significant decrease in maximum photosynthetic CO2 assimilation and stomatal conductance at high levels of the pollutant, while changes in mesophyll conductance were not significant. However, under HNO3 fumigation there was a significant increase in mesophyll conductance at low and high HNO3 levels while changes in maximum photosynthetic CO2 assimilation and stomatal conductance were not significant. We could not detect any activity of the antioxidant enzymes in the fumigated tobacco leaves. This is in spite of the fact that we were able to assay the enzymes in tobacco leaves grown in Israel. Conclusions. This project generated novel data, and potentially applicable to agriculture, on the differential response of lichens and tobacco to HNO3 and O3 pollutants. However, due to experimental problems and time limitation discussed in the body of the report, our data do not justify yet application for a full, 4-year grant. We hope that in the future we shall conduct more experiments related to our objectives, which will serve as a basis for a larger scale project to explore the possibility of using lichens and/or plants for biomonitoring of ozone and nitric acid air pollution.
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Philosoph-Hadas, Sonia, Peter Kaufman, Shimon Meir y Abraham Halevy. Signal Transduction Pathway of Hormonal Action in Control and Regulation of the Gravitropic Response of Cut Flowering Stems during Storage and Transport. United States Department of Agriculture, octubre de 1999. http://dx.doi.org/10.32747/1999.7695838.bard.

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Original objectives: The basic goal of the present project was to increase our understanding of the cellular mechanisms operating during the gravitropic response of cut flowers, for solving their bending problem without affecting flower quality. Thus, several elements operating at the 3 levels o the gravity-induced signal transduction pathway, were proposed to be examined in snapdragon stems according to the following research goals: 1) Signaling: characterize the signal transduction pathway leading to the gravitropic response, regarding the involvement of [Ca2+]cyt as a mediator of IAA movement and sensitivity to auxin. 2) Transduction by plant hormones: a) Examine the involvement of auxin in the gravitropic response of flower stems with regard to: possible participation of auxin binding protein (ABP), auxin redistribution, auxin mechanism of action (activation of H+-ATPase) mediation by changes in [Ca2+]cyt and possible regulation of auxin-induced Ca2+ action b: calmodulin-activated or Ca2+-activated protein kinases (PK). b) Examine the involvement of ethylene in the gravitropic response of flower stems with regard to auxin-induced ethylene production and sensitivity of the tissue to ethylene. 3) Response: examine the effect of gravistimulation on invertase (associated with growth and elongation) activity and invertase gene expression. 4) Commercial practice: develop practical and simple treatments to prevent bending of cut flowers grown for export. Revisions: 1) Model systems: in addition to snapdragon (Antirrhinum majus L.), 3 other model shoe systems, consisting of oat (Avena sativa) pulvini, Ornithogalun 'Nova' cut flowers and Arabidopsis thaliana inflorescence, were targeted to confirm a more general mechanism for shoot gravitropism. 2 Research topics: the involvement of ABP, auxin action, PK and invertase in the gravitropic response of snapdragon stems could not be demonstrated. Alternatively, the involvement in the gravity signaling cascade of several other physiological mediators apart of [Ca2+]cyt such as: IP3, protein phosphorylation and actin cytoskeleton, was shown. Additional topics introduced: starch statolith reorientation, differential expression of early auxin responsive genes, and differential shoot growth. Background to the topic: The gravitropic bending response of flowering shoots occurring upon their horizontal placement during shipment exhibits a major horticultural problem. In spite of extensive studies in various aboveground organs, the gravitropic response was hardly investigated in flowering shoots. Being a complex multistep process that requires the participation of various cellular components acting in succession or in parallel, analysis of the negative gravitropic response of shoot includes investigation of signal transduction elements and various regulatory physiological mediators. Major achievements: 1) A correlative role for starch statoliths as gravireceptors in flowering shoot was initially established. 2) Differentially phosphorylated proteins and IP3 levels across the oat shoe pulvini, as well as a differential appearance of 2 early auxin-responsive genes in snapdragon stems were all detected within 5-30 minutes following gravistimulation. 3) Unlike in roots, involvement of actin cytoskeleton in early events of the gravitropic response of snapdragon shoots was established. 4) An asymmetric IAA distribution, followed by an asymmetric ethylene production across snapdragon stems was found following gravistimulation. 5) The gravity-induced differential growth in shoots of snapdragon was derived from initial shrinkage of the upper stem side and a subsequent elongation o the lower stem side. 6) Shoot bending could be successfully inhibited by Ca2+ antagonists (that serve as a basis for practical treatments), kinase and phosphatase inhibitors and actin-cytoskeleton modulators. All these agents did not affect vertical growth. The essential characterization of these key events and their sequence led us to the conclusion that blocking gravity perception may be the most powerful means to inhibit bending without hampering shoot and flower growth after harvest. Implications, scientific and agriculture: The innovative results of this project have provided some new insight in the basic understanding of gravitropism in flower stalks, that partially filled the gap in our knowledge, and established useful means for its control. Additionally, our analysis has advanced the understanding of important and fundamental physiological processes involved, thereby leading to new ideas for agriculture. Gravitropism has an important impact on agriculture, particularly for controlling the bending of various important agricultural products with economic value. So far, no safe control of the undesired bending problem of flower stalks has been established. Our results show for the first time that shoot bending of cut flowers can be inhibited without adverse effects by controlling the gravity perception step with Ca2+ antagonists and cytoskeleton modulators. Such a practical benefit resulting from this project is of great economic value for the floriculture industry.
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