Relevant bibliographies by topics / Spike density

Academic literature on the topic 'Spike density'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Spike density"

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Diggelmann, Roland, Michele Fiscella, Andreas Hierlemann, and Felix Franke. "Automatic spike sorting for high-density microelectrode arrays." Journal of Neurophysiology 120, no. 6 (December 1, 2018): 3155–71. http://dx.doi.org/10.1152/jn.00803.2017.

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High-density microelectrode arrays can be used to record extracellular action potentials from hundreds to thousands of neurons simultaneously. Efficient spike sorters must be developed to cope with such large data volumes. Most existing spike sorting methods for single electrodes or small multielectrodes, however, suffer from the “curse of dimensionality” and cannot be directly applied to recordings with hundreds of electrodes. This holds particularly true for the standard reference spike sorting algorithm, principal component analysis-based feature extraction, followed by k-means or expectation maximization clustering, against which most spike sorters are evaluated. We present a spike sorting algorithm that circumvents the dimensionality problem by sorting local groups of electrodes independently with classical spike sorting approaches. It is scalable to any number of recording electrodes and well suited for parallel computing. The combination of data prewhitening before the principal component analysis-based extraction and a parameter-free clustering algorithm obviated the need for parameter adjustments. We evaluated its performance using surrogate data in which we systematically varied spike amplitudes and spike rates and that were generated by inserting template spikes into the voltage traces of real recordings. In a direct comparison, our algorithm could compete with existing state-of-the-art spike sorters in terms of sensitivity and precision, while parameter adjustment or manual cluster curation was not required. NEW & NOTEWORTHY We present an automatic spike sorting algorithm that combines three strategies to scale classical spike sorting techniques for high-density microelectrode arrays: 1) splitting the recording electrodes into small groups and sorting them independently; 2) clustering a subset of spikes and classifying the rest to limit computation time; and 3) prewhitening the spike waveforms to enable the use of parameter-free clustering. Finally, we combined these strategies into an automatic spike sorter that is competitive with state-of-the-art spike sorters.
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Nwry, Rezhin Ghareb, Shang Haseeb Abdulqader, and Shwana Ahmad Hussain. "Effect of plant population and cultivars on growth, yield and its component of bread wheat (Triticum aestivum L.) under the rain-fed condition in Kurdistan- Iraq." Tikrit journal for agricultural sciences 21, no. 3 (September 30, 2021): 41–51. http://dx.doi.org/10.25130/tjas.21.3.5.

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This experiment was conducted at the research field of College of Agricultural Engineering Sciences-University of Sulaimani at Bakrajo, Sulaimani, Iraq during the growing season of 2016-2017 to assess the effect of three-row spaces (10, 15 and 20) cm and three plant densities (160, 200 and 240) kg/ha with their interaction on grain yield and yield components of two bread wheat cultivars (Adana-99 and Aras). For each trait, ranges of statistical analysis were performed, including a Factorial Experiment in a Completely Randomized Block Design (CRBD) with three replications. At a 5% significance level, mean comparisons were done using the least significant difference (L.S.D). Plant height, number of spikes/m2, spike length, spike weight, number of spikelets/spike, number of grain/spike, the weight of grain/spike, 1000-grain weight, harvest index, biological yield, and grain yield were all calculated as part of grain yield. The results show that row spaces have a significant impact on the studied characters, with 10 cm producing the highest values for all characteristics except the number of spikes/m2, spike length, and harvest index, which were provided by 15 cm. With the exception of the number of spikes/m2, spike length, and biological yields, the impact of varieties on agronomic traits was significant; the Adana-99 variety provided maximum values for all of the studied characters. With the exception of spike length, where 200kg/ha density had the ultimate value, plant density had a major impact on the studied characters, with 160kg/ha density producing maximum values for almost all of the characters, and 240kg/ha density producing maximum values for the number of spikes/m2 and biological yield. Based on our findings, the Adana-99 cultivar should be sown at a seed rate of 160 kg/ha with a 10 cm inter-row spacing in Bakrajo, Sulaimani Region under guaranteed rained conditions.
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Paunovic, Aleksandar, Desimir Knezevic, and Milomirka Madic. "Genotype variations in grain yield of spring barley depending on sowing density." Genetika 38, no. 2 (2006): 107–14. http://dx.doi.org/10.2298/gensr0602107k.

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A three-year study was carried out for grain yield in five cultivars of the spring brewer's barley at the Small Grains Research Center of in Kragujevac from 1996 to 1998. The effect of three sowing densities on the number of spikes, grain number per spike and grain yield was studied for each cultivars. Research results have shown that the cultivars displayed a highly significant effect on the grain number per spike and grain yield. It has also been noticed that, in the course of every research year, sowing density induced increases in spike number and grain yield. In contrast, the higher sowing density brought about a decrease in the grain number per spike.
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Uramoto, Takumi, and Hiroyuki Torikai. "A Calcium-Based Simple Model of Multiple Spike Interactions in Spike-Timing-Dependent Plasticity." Neural Computation 25, no. 7 (July 2013): 1853–69. http://dx.doi.org/10.1162/neco_a_00462.

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Spike-timing-dependent plasticity (STDP) is a form of synaptic modification that depends on the relative timings of presynaptic and postsynaptic spikes. In this letter, we proposed a calcium-based simple STDP model, described by an ordinary differential equation having only three state variables: one represents the density of intracellular calcium, one represents a fraction of open state NMDARs, and one represents the synaptic weight. We shown that in spite of its simplicity, the model can reproduce the properties of the plasticity that have been experimentally measured in various brain areas (e.g., layer 2/3 and 5 visual cortical slices, hippocampal cultures, and layer 2/3 somatosensory cortical slices) with respect to various patterns of presynaptic and postsynaptic spikes. In addition, comparisons with other STDP models are made, and the significance and advantages of the proposed model are discussed.
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Smith, M. A. H., and R. J. Lamb. "Factors influencing oviposition by Sitodiplosis mosellana (Diptera: Cecidomyiidae) on wheat spikes (Gramineae)." Canadian Entomologist 133, no. 4 (August 2001): 533–48. http://dx.doi.org/10.4039/ent133533-4.

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AbstractFactors that might contribute to variability in the densities of wheat midge eggs, Sitodiplosis mosellana (Géhin), on common and durum wheats, Triticum aestivum L. and Triticum durum Desf., were investigated to improve the quantification of oviposition preferences in relation to crop resistance. Egg densities on wheat spikes were highly variable, with a similar contagious distribution in the laboratory and field, although variance was highest in the laboratory. Females laid eggs in small groups, usually of one to six eggs; most infested spikes had more than one egg group. Females showed no preference for ovipositing on different parts of a spike, although spikelets on one side and at the base often received fewer eggs because these spikelets were covered by the flag leaf and inaccessible for longer than others. Oviposition rates varied from night to night, probably related to the weather. Females showed no preference for spikes at different growth stages, from the time spikes began to emerge until at least flowering. Spike size did not affect egg density, and spike height was a factor only for spikes deep within or protruding above the canopy. Sources of environmental variation such as effects of weather on oviposition rates in the field or spatial phenomena in cages were measurable but of secondary importance. In the field, comparisons among spikes which emerged on the same day could reduce variation in egg density. In the laboratory, variation in egg density could be reduced by using arrays of excised spikes arranged at the same height, leaving the central portion of the array empty. The primary cause of high variability in egg density among spikes was variation in egg-group size and the presence of multiple egg groups on a single spike, factors which cannot be experimentally controlled because they are the result of oviposition behaviour rather than environmental heterogeneity.
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Daghigh, Ramin G., and Gabor Kunstatter. "Spacetime Metrics and Ringdown Waveforms for Galactic Black Holes Surrounded by a Dark Matter Spike." Astrophysical Journal 940, no. 1 (November 1, 2022): 33. http://dx.doi.org/10.3847/1538-4357/ac940b.

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Abstract Theoretical models suggest the existence of a dark matter spike surrounding the supermassive black holes at the core of galaxies. The spike density is thought to obey a power law that starts at a few times the black hole horizon radius and extends to a distance, R sp, of the order of a kiloparsec. We use the Tolman–Oppenheimer–Volkoff equations to construct the spacetime metric representing a black hole surrounded by such a dark matter spike. We consider the dark matter to be a perfect fluid, but make no other assumption about its nature. The assumed power-law density provides in principle three parameters with which to work: the power-law exponent γ sp, the external radius R sp, and the spike density ρ DM sp at R sp. These in turn determine the total mass of the spike. We focus on Sagittarius A* and M87 for which some theoretical and observational bounds exist on the spike parameters. Using these bounds in conjunction with the metric obtained from the Tolman–Oppenheimer–Volkoff equations, we investigate the possibility of detecting the dark matter spikes surrounding these black holes via the gravitational waves emitted at the ringdown phase of black hole perturbations. Our results suggest that if the spike to black hole mass ratio is roughly constant, greater mass black holes require relatively smaller spike densities to yield potentially observable signals. We find that is unlikely for the spike in M87 to be detected via the ringdown waveform with currently available techniques unless its mass is roughly an order of magnitude larger than existing observational estimates. However, given that the signal increases with black hole mass, dark matter spikes might be observable for more massive galactic black holes in the not too distant future.
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Galimidi, Rachel, Joshua Klein, Maria Politzer, Shiyu Bai, Michael Seaman, Michel Nussenzweig, Anthony West, and Pamela Bjorkman. "Intra-spike crosslinking overcomes antibody evasion by HIV-1 (VIR1P.1131)." Journal of Immunology 194, no. 1_Supplement (May 1, 2015): 74.8. http://dx.doi.org/10.4049/jimmunol.194.supp.74.8.

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Abstract Antibodies developed during HIV-1 infection lose efficacy as the viral spike mutates. We postulated that anti-HIV-1 antibodies primarily bind monovalently because HIV’s low spike density impedes bivalent binding through inter-spike crosslinking, and the spike structure prohibits bivalent binding through intra-spike crosslinking. Monovalent binding reduces avidity and potency, thus expanding the range of mutations permitting antibody evasion. To test this idea, we engineered antibody-based molecules capable of bivalent binding through intra-spike crosslinking. We used DNA as a “molecular ruler” to measure intra-epitope distances on virion-bound spikes and construct intra-spike crosslinking molecules. Optimal bivalent reagents exhibited up to 2.5 orders-of-magnitude increased potency (>100-fold average increases across virus panels) and identified conformational states of virion-bound spikes. The demonstration that intra-spike crosslinking lowers the concentration of antibodies required for neutralization supports the hypothesis that low spike densities facilitate antibody evasion and the use of molecules capable of intra-spike crosslinking for therapy or passive protection.
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Alvarez, J., J. Gómez, A. Martín, and L. Martín. "Gene effects for spike length, spikelets per spike and spike density inHordeum chilense." Cereal Research Communications 38, no. 2 (June 2010): 266–71. http://dx.doi.org/10.1556/crc.38.2010.2.13.

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VAN DIJCK, GERT, KARSTEN SEIDL, OLIVER PAUL, PATRICK RUTHER, MARC M. VAN HULLE, and REINOUD MAEX. "ENHANCING THE YIELD OF HIGH-DENSITY ELECTRODE ARRAYS THROUGH AUTOMATED ELECTRODE SELECTION." International Journal of Neural Systems 22, no. 01 (February 2012): 1–19. http://dx.doi.org/10.1142/s0129065712003055.

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Recently developed CMOS-based microprobes contain hundreds of electrodes on a single shaft with inter-electrode distances as small as 30 μm. So far, neuroscientists needed to select electrodes manually from hundreds of electrodes. Here we present an electronic depth control algorithm that allows to select electrodes automatically, hereby allowing to reduce the amount of data and locating those electrodes that are close to neurons. The electrodes are selected according to a new penalized signal-to-noise ratio (PSNR) criterion that demotes electrodes from becoming selected if their signals are redundant with previously selected electrodes. It is shown that, using the PSNR, interneurons generating smaller spikes are also selected. We developed a model that aims to evaluate algorithms for electronic depth control, but also generates benchmark data for testing spike sorting and spike detection algorithms. The model comprises a realistic tufted pyramidal cell, non-tufted pyramidal cells and inhibitory interneurons. All neurons are synaptically activated by hundreds of fibers. This arrangement allows the algorithms to be tested in more realistic conditions, including backgrounds of synaptic potentials, varying spike rates with bursting and spike amplitude attenuation.
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De Zeeuw, C. I., S. K. E. Koekkoek, D. R. W. Wylie, and J. I. Simpson. "Association Between Dendritic Lamellar Bodies and Complex Spike Synchrony in the Olivocerebellar System." Journal of Neurophysiology 77, no. 4 (April 1, 1997): 1747–58. http://dx.doi.org/10.1152/jn.1997.77.4.1747.

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De Zeeuw, C. I., S.K.E. Koekkoek, D.R.W. Wylie, and J. I. Simpson. Association between dendritic lamellar bodies and complex spike synchrony in the olivocerebellar system. J. Neurophysiol. 77: 1747–1758, 1997. Dendritic lamellar bodies have been reported to be associated with dendrodendritic gap junctions. In the present study we investigated this association at both the morphological and electrophysiological level in the olivocerebellar system. Because cerebellar GABAergic terminals are apposed to olivary dendrites coupled by gap junctions, and because lesions of cerebellar nuclei influence the coupling between neurons in the inferior olive, we postulated that if lamellar bodies and gap junctions are related, then the densities of both structures will change together when the cerebellar input is removed. Lesions of the cerebellar nuclei in rats and rabbits resulted in a reduction of the density of lamellar bodies, the number of lamellae per lamellar body, and the density of gap junctions in the inferior olive, whereas the number of olivary neurons was not significantly reduced. The association between lamellar bodies and electrotonic coupling was evaluated electrophysiologically in alert rabbits by comparing the occurrence of complex spike synchrony in different Purkinje cell zones of the flocculus that receive their climbing fibers from olivary subnuclei with different densities of lamellar bodies. The complex spike synchrony of Purkinje cell pairs, that receive their climbing fibers from an olivary subnucleus with a high density of lamellar bodies, was significantly higher than that of Purkinje cells, that receive their climbing fibers from a subnucleus with a low density of lamellar bodies. To investigate whether the complex spike synchrony is related to a possible synchrony between simple spikes, we recorded simultaneously the complex spike and simple spike responses of Purkinje cell pairs during natural visual stimulation. Synchronous simple spike responses did occur, and this synchrony tended to increase as the synchrony between the complex spikes increased. This relation raises the possibility that synchronously activated climbing fibers evoke their effects in part via the simple spike response of Purkinje cells. The present results indicate that dendritic lamellar bodies and dendrodendritic gap junctions can be downregulated concomitantly, and that the density of lamellar bodies in different olivary subdivisions is correlated with the degree of synchrony of their climbing fiber activity. Therefore these data support the hypothesis that dendritic lamellar bodies can be associated with dendrodendritic gap junctions. Considering that the density of dedritic lamellar bodies in the inferior olive is higher than in any other area of the brain, this conclusion implies that electrotonic coupling is important for the function of the olivocerebellar system.
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Dissertations / Theses on the topic "Spike density"

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Leibig, Christian [Verfasser], and Matthias [Akademischer Betreuer] Bethge. "Unsupervised neural spike identification for large-scale, high-density micro-electrode arrays / Christian Leibig ; Betreuer: Matthias Bethge." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1164018396/34.

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Hassanpour, Hamid. "Time-frequency based detection of newborn EEG seizure." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15853/1/Hamid_Hassanpour_Thesis.pdf.

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Neurological diseases in newborns are usually first revealed by seizures, which are characterised by a synchronous discharge of a large number of neurons. Failure to control seizures may lead to brain damage or even death. The importance of this problem prompted many researchers to look for accurate automatic methods for seizure detection. Nonstationarity and multicomponent behaviour of newborn EEG signals made this task very challenging. The significant overlap in the characteristic of background and seizure activities in newborn EEG signals added to the difficulty of seizure detection. This research uses time-frequency based methods for automatic seizure detection. Since time-frequency signal analysis methods use joint representation in both time and frequency domains, they proved to be very suitable for analysis and processing of nonstationary and multicomponent signals such as newborn EEG. Before using any seizure detector, the EEG data is pre-processed in order to reduce the noise effects using a time-frequency based technique. The proposed method is based on the singular value decomposition (SVD) technique applied to the matrix representing the time-frequency distribution (TFD) of the EEG signal. It has been shown that by appropriately filtering the singular vectors associated with the TFD, one can effectively enhance the desired information embedded in the signal. Neonatal EEG seizures can have signatures in both low frequency (lower than 10 Hz) and high frequency (higher than 70 Hz) areas. The seizure detection techniques proposed in the literature concentrated on using either low frequency or high frequency signatures but not both simultaneously. These methods tend to miss the seizures that reveal themselves only in one of the two frequency areas. In this research, we propose a detection method that uses seizure features in both low and high frequency areas. To detect EEG seizures using the low frequency signatures, an SVD-based technique is employed. The technique uses the estimated distribution function of the singular vectors associated with the time-frequency distribution of EEG epochs to discriminate between seizure and nonseizure patterns. The high frequency signatures of seizures are mostly the result of spike events in the EEG signals. To detect these spike events, the signal is mapped into the TF domain. The high instantaneous energy of spikes is reflected as a localised energy in the high frequency area of the TF domain. Consequently, a spike can be seen as a ridge in this area of the TF domain. It has been shown that during seizure activity there is regularity in the distribution of the interspike intervals. This feature has been used as the basis for discriminating between seizure and nonseizure patterns. The performance results obtained by applying the proposed methods on EEG signals extracted from a number of newborns show the superiority of these methods over the existing ones.
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Hassanpour, Hamid. "Time-Frequency Based Detection of Newborn EEG Seizure." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15853/.

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Neurological diseases in newborns are usually first revealed by seizures, which are characterised by a synchronous discharge of a large number of neurons. Failure to control seizures may lead to brain damage or even death. The importance of this problem prompted many researchers to look for accurate automatic methods for seizure detection. Nonstationarity and multicomponent behaviour of newborn EEG signals made this task very challenging. The significant overlap in the characteristic of background and seizure activities in newborn EEG signals added to the difficulty of seizure detection. This research uses time-frequency based methods for automatic seizure detection. Since time-frequency signal analysis methods use joint representation in both time and frequency domains, they proved to be very suitable for analysis and processing of nonstationary and multicomponent signals such as newborn EEG. Before using any seizure detector, the EEG data is pre-processed in order to reduce the noise effects using a time-frequency based technique. The proposed method is based on the singular value decomposition (SVD) technique applied to the matrix representing the time-frequency distribution (TFD) of the EEG signal. It has been shown that by appropriately filtering the singular vectors associated with the TFD, one can effectively enhance the desired information embedded in the signal. Neonatal EEG seizures can have signatures in both low frequency (lower than 10 Hz) and high frequency (higher than 70 Hz) areas. The seizure detection techniques proposed in the literature concentrated on using either low frequency or high frequency signatures but not both simultaneously. These methods tend to miss the seizures that reveal themselves only in one of the two frequency areas. In this research, we propose a detection method that uses seizure features in both low and high frequency areas. To detect EEG seizures using the low frequency signatures, an SVD-based technique is employed. The technique uses the estimated distribution function of the singular vectors associated with the time-frequency distribution of EEG epochs to discriminate between seizure and nonseizure patterns. The high frequency signatures of seizures are mostly the result of spike events in the EEG signals. To detect these spike events, the signal is mapped into the TF domain. The high instantaneous energy of spikes is reflected as a localised energy in the high frequency area of the TF domain. Consequently, a spike can be seen as a ridge in this area of the TF domain. It has been shown that during seizure activity there is regularity in the distribution of the interspike intervals. This feature has been used as the basis for discriminating between seizure and nonseizure patterns. The performance results obtained by applying the proposed methods on EEG signals extracted from a number of newborns show the superiority of these methods over the existing ones.
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Oppong, Francis. "Prenatal Alcohol Exposure Reduces Dendritic Spine Density across Sensory Cortices." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2482.

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Dendritic spines are the major site of excitatory synapses in cortex, and factors that reduce dendritic spine numbers will produce serious cortical processing deficits, such as has been demonstrated for mental retardation and other psychiatric disorders. Prenatal alcohol exposure also has detrimental effects on brain development that lead to Fetal Alcohol Spectrum Disorder (FASD), which results in reduction of dendritic spine numbers in the hippocampus, prefrontal cortex and somatosensory cortex. FASD also is associated with temporal processing disorders involving sequential auditory stimuli that would be processed in auditory cortical areas. However, it is unknown if the reduction of spine density following prenatal alcohol exposure occurs at auditory cortex, or is generally reduced across the different sensory cortices. This present study examined that question. Young adult ferrets (176 days old, 1 male, 1 female), that were exposed to alcohol during the equivalent of third-trimester development, were used to prepare Golgi-Cox stained sections through primary auditory cortex (A1). Other cortical regions examined included primary somatosensory (S1), and higher-level multisensory cortices of lateral rostral suprasylvian (LRSS) and rostral posterior parietal (PPr) areas. Control values from normal animals (n=3) were derived from a previous study. The results of this present study demonstrated that, dendritic spine density was significantly (Student's t-test, P < 0.05) lower in the alcohol treated group than in normal controls in all the cortical regions examined. These data indicate that although reduced spine density in auditory cortex may underlie temporal processing disorders in FASD, pre-natal alcohol exposure has widespread consequences for sensory cortical processing in general.
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Bajwa, Moazzum. "Dendritic Spine Density Varies Between Unisensory and Multisensory Cortical Regions." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/87.

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In the brain, the dendritic spine is a point of information exchange that extends the neuronal surface on which synapses occur, as well as facilitates and stabilizes those contacts. Furthermore, dendritic spines dynamically change in shape and number in response to a variety of factors. Dendritic spine numbers are reduced in mental retardation, enhanced during development, sensory enrichment or physical exercise, or fluctuate during the reproductive cycle. Thus, for a given neuron type, it might be expected that dendritic spine number might achieve a dynamic optimum. Indeed, many studies of spine density of pyramidal neurons in sensory cortex indicate that an average of ~1.4 spines/micron occurs is present (Briner et al., 2010). Most such studies examined dendritic spines from primary sensory areas which are dominated by inputs from a single sensory modality. However, there are a large number of neural regions that receive inputs from more than one sensory modality and it is hypothesized that spine density should increase to accommodate these additional inputs. To test this hypothesis, the present experiments used Golgi-Cox stained layer 2-3 pyramidal neurons from ferret primary somatosensory (S1) and auditory (A1) cortical regions, as well as from the higher-level rostral posterior parietal (PPr) and lateral rostral suprasylvian (LRSS) multisensory areas. Spine densities in S1 (avg 1.309 ± 0.247 spines/micron) and A1 (avg 1.343 ± 0.273 spines/micron) were measured to be significantly greater (p<0.05, t-test) than those observed in multisensory regions PPr (avg 1.242 ± 0.205 spines/micron) or LRSS (avg 1.099 ± 0.217 spines/micron). These results also indicate that spine densities are greater in primary (S1, A1) than in higher-level (PPr, LRSS) sensory areas. The functional consequences of such unexpected findings are discussed in light of potential biophysical differences between unisensory and multisensory neurons.
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Fong, Lisa Lynn. "Purkinje cell dendritic spine density from correlated three dimensional light and electron microscopy." Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/fullcit?p1477900.

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Thesis (M.S.)--University of California, San Diego, 2010.
Title from first page of PDF file (viewed July 12, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (leaves 57-62).
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Bauer, Rachel J. "THE EFFECTS OF LONG-TERM DEAFNESS ON DENSITY AND DIAMETER OF DENDRITIC SPINES ON PYRAMIDAL NEURONS IN THE DORSAL ZONE OF THE FELINE AUDITORY CORTEX." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6028.

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Neuroplasticity has been researched in many different ways, from the growing neonatal brain to neural responses to trauma and injury. According to recent research, neuroplasticity is also prevalent in the ability of the brain to repurpose areas that are not of use, like in the case of a loss of a sense. Specifically, behavioral studies have shown that deaf humans (Bavalier and Neville, 2002) and cats have increased visual ability, and that different areas of the auditory cortex enhance specific kinds of sight. One such behavioral test demonstrated that the dorsal zone (DZ) of the auditory cortex enhances sensitivity to visual motion through cross-modal plasticity (Lomber et. al., 2010). Current research seeks to examine the anatomical structures responsible for these changes through analysis of excitatory neuron dendritic spine density and spine head diameter. This present study focuses on the examination of DZ neuron spine density, distribution, and size in deaf and hearing cats to corroborate the visual changes seen in behavioral studies. Using Golgi-stained tissue and light microscopy, our results showed a decrease in overall spine density but slight increase in spine head diameter in deaf cats compared to hearing cats. These results, along with several other studies, support multiple theories on how cross-modal reorganization of the auditory cortex occurs after deafening
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Strong, J. Eric. "Effects of Different Jumping Programs on Hip and Spine Bone Mineral Density in Pre-Menopausal Women." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/667.

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Sixty premenopausal women (age 25-50) finished a 16 week randomized controlled trial looking at the effects of different jump programs on hip and spine bone mineral density (BMD). Subjects were randomly assigned to a control group or one of two jumping groups. The Jump 10 group performed 10 jumps with 30 seconds of rest between jumps, twice daily, while the Jump 20 group performed the same protocol but with 20 jumps. At 8 weeks, BMD percent change (%Δ) at the hip was significantly different among groups when age, weight change, and subject compliance were simultaneously adjusted. In particular, the Jump 20 group had a greater %Δ in hip BMD compared to controls. However, %Δ in BMD for the neck of the hip (NOH), trochanter, or spine was not different among groups at 8 weeks. Following 16 weeks of jumping, BMD %Δ at the total hip and trochanter were significantly different among groups after adjusting for all covariates. Specifically, at the hip and trochanter, the Jump 10 and Jump 20 groups showed significantly greater %Δ in BMD compared to controls. There were no significant differences among groups for the BMD %Δ at NOH or spine at 16 weeks. Within-group analyses revealed no significant changes from baseline to 16 weeks for the jumping groups, but controls lost significant BMD. In conclusion, after 16 weeks of high-impact jump training, BMD at the hip and trochanter can be improved by jumping 10 or 20 times, twice daily, with 30 seconds of rest between each jump, compared to controls.
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Whitcher, Lee T. "Postnatal binge-like alcohol exposure reduces spine density without affecting dendritic morphology in rat medial prefrontal cortex." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 34 p, 2008. http://proquest.umi.com/pqdweb?did=1459903421&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Lewerenz, Martha Elisabeth [Verfasser], and Gabriele [Akademischer Betreuer] Rune. "Hippocampal aromatase expression and spine synapse density in reeler mutant mouse / Martha Elisabeth Lewerenz ; Betreuer: Gabriele Rune." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1161847499/34.

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Books on the topic "Spike density"

1

Brueckner, Jan K. Fares and network 'feed': Estimating economies of traffic density in airline hub-and-spoke systems. Champaign: University of Illinois at Urbana-Champaign, 1991.

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National Center for Health Statistics (U.S.) and National Health and Nutrition Examination Survey (U.S.), eds. Lumbar spine and proximal femur bone mineral density, bone mineral content, and bone area, United States, 2005-2008: Data from the National Health and Nutrition Examnination Survey (NHANES). Hyattsville, Md: U.S. Dept. of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics, 2012.

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Wang, Shi Ping. Influence of planting density on spike size and grain yield in five winter wheat cultivars. 1990.

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High Density Packaging and McMs (Proceedings of SPIE). Society of Photo Optical, 1999.

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Goldenberg, Deborah Susan *. Enhancement of synaptic density through conservation of axial volume: a novel approach to the question of function of the dendritic spine. 1989.

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Hoftman, Gil D., and Dean F. Salisbury. Neurobiology of Schizophrenia. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199331505.003.0005.

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Schizophrenia is a brain disease with unknown etiology; a variety of neurodevelopmental mechanisms contribute to its pathogenesis. In this chapter, we review some of the most salient neurobiological findings that seem to be linked with the pathophysiology of psychosis generally and schizophrenia specifically. Several important findings have been made from neuroimaging and neuropathology, including reduced whole-brain volume, enlarged ventricles, and decreased cortical gray matter. Abnormalities in the prefrontal cortex, such as decreased dendritic spine density, are particularly important for cognitive and negative symptoms in schizophrenia. Functional imaging suggests that patterns of activation may be closely linked to symptom clusters. We will review neurotransmitter abnormalities, especially dopamine but also glutamate and GABA, and relevant circuitry and connectivity problems related to pathology. Finally, we will discuss genetics and heritability, and the challenges of identifying relevant loci in such a complex disorder.
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Proceedings: 2001 HD International Conference on High-Density Interconnect and Systems Packaging : April 17-20, 2001, Santa Clara Convention Center, Santa Clara, California (SPIE proceedings series). Published in cooperation with SPIE, 2001.

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Wolman, Roger. Sports injuries in the pelvic region. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199550647.003.007015.

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♦ The pelvis acts as a fulcrum for the forces transmitted between the lower limb and trunk especially on twisting and turning movements while running, and in the reverse direction when kicking. Sports injuries around the pelvis are therefore common in weight-bearing sports, such as running, football, rugby, and basketball♦ Injury can occur to the various structures around the pelvis. Bone stress injuries affect the symphysis pubis, pubic rami, femoral neck, and sacrum. Stress fractures are more common in women and may occur as part of the female athlete triad (Box 7.15.1) where there is hypo-oestrogenaemia and low bone density♦ Tendon injuries, including enthesopathies, most commonly affect the adductors, lower abdominals, glutei and hamstrings. Hip injuries can occur as a result of labral tears and femoroacetabular impingement. Sacroiliac joint instability may also cause symptoms especially in the buttock region. Synovitis of either joint may suggest an inflammatory arthritis♦ Pain is the most common symptom. However it may be referred from elsewhere, especially the lumbar spine. Pain may also originate from other systems including the reproductive organs and the gastrointestinal and urinary tracts.
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Elder, Grahame J. Metabolic bone disease after renal transplantation. Edited by Jeremy R. Chapman. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0288.

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Patients who undergo kidney transplantation have laboratory, bone, and soft tissue abnormalities that characterize chronic kidney disease mineral and bone disorder (CKD-MBD). After successful transplantation, abnormal values of parathyroid hormone, fibroblast growth factor 23, calcium, phosphate, vitamin D sterols, and sex hormones generally improve, but abnormalities often persist. Cardiovascular risk remains high and is influenced by prevalent vascular calcification, and fracture risk increases due to a combination of abnormal bone ‘quality’, compounded by immunosuppressive drugs and reductions in bone mineral density. Patients with well managed CKD-MBD before transplantation generally have a smoother post-transplant course, and it is useful to assess patients soon after transplantation for risk factors relevant to the general population and to patients with CKD. Targeted laboratory assessment, bone densitometry, and X-ray of the spine are useful for guiding therapy to minimize post-transplant effects of CKD-MBD. To reduce fracture risk, general measures include glucocorticoid dose minimization, attaining adequate 25(OH)D levels, and maintaining calcium and phosphate values in the normal range. Calcitriol or its analogues and antiresorptive agents such as bisphosphonates may protect bone from glucocorticoid effects and ongoing hyperparathyroidism, but the efficacy of these therapies to reduce fractures is unproven. Alternate therapies with fewer data include denosumab, strontium ranelate, teriparatide, oestrogen or testosterone hormone replacement therapy, tibolone, selective oestrogen receptor modulators, and cinacalcet. Parathyroidectomy may be necessary, but is generally avoided within the first post-transplant year. A schema is presented in this chapter that aims to minimize harm when allocating therapy.
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Book chapters on the topic "Spike density"

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Holleman, Jeremy, Fan Zhang, and Brian Otis. "NeuralWISP: A Wirelessly Powered Spike Density Recording System." In Ultra Low-Power Integrated Circuit Design for Wireless Neural Interfaces, 97–110. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-6727-5_10.

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Divjak, Matjaž, Lukas G. Wiedemann, Andrew J. McDaid, and A. Holobar. "On the Crosstalk in Motor Unit Spike Train Identification from High-Density Surface Electromyograms." In Biosystems & Biorobotics, 389–93. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70316-5_62.

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Holobar, A., and V. Glaser. "Cumulative Spike Train Outperforms the Root-Mean-Square Metric in Muscle Excitation Estimation from Dynamic High-Density EMG." In Converging Clinical and Engineering Research on Neurorehabilitation III, 1143–47. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-01845-0_228.

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Lundqvist, Udda. "Scandinavian mutation research during the past 90 years - a historical review." In Mutation breeding, genetic diversity and crop adaptation to climate change, 10–23. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0002.

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Abstract In 1928, the Swedish geneticists Herman Nilsson-Ehle and Åke Gustafsson started to act on their own ideas with the first experiments with induced mutations using diploid barley. They started with X-rays and UV irradiation. Very soon the first chlorophyll mutations were obtained and followed by the first 'vital' mutations Erectoides (ert) (Franckowiak and Lundqvist, 2001). Several other valuable mutations were identified as early maturity, high yielding, lodging resistant and characters with altered plant architecture. The experiments expanded to include other different types of irradiation, followed by chemical mutagenesis starting with mustard gas and concluding with sodium azide. The research brought a wealth of observations of general biological importance, such as the physiological effects of radiation as well as the difference in the mutation spectrum with respect to mutagens. This research was non-commercial, even if some mutants have become of important agronomic value. It peaked in activity during the 1950s to 1980s and, throughout, barley was the main experimental crop. About 12,000 different morphological and physiological mutants with a very broad phenotypic diversity were brought together and are incorporated in the Nordic Genetic Resource Centre (NordGen), Sweden. Several important mutant groups have been analysed in more detail genetically, with regard to mutagen specificity and gene cloning. These are: (i) early maturity mutants (Praematurum); (ii) six-rowed and intermedium-spike mutants; (iii) mutants affecting surface wax coating (Eceriferum); and (iv) mutants affecting rachis spike density (Erectoides). Some of these groups are presented in more detail in this review. Once work with induction of mutations began, it was evident that mutations should regularly be included in breeding programmes of crop plants. In Sweden, direct X-ray induced macro-mutants have been successfully released as cultivars, some of them having been used in combination breeding. Their importance for breeding is discussed in more detail.
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Malavena, Gerardo. "Modeling of GIDL–Assisted Erase in 3–D NAND Flash Memory Arrays and Its Employment in NOR Flash–Based Spiking Neural Networks." In Special Topics in Information Technology, 43–53. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-85918-3_4.

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AbstractSince the very first introduction of three-dimensional (3–D) vertical-channel (VC) NAND Flash memory arrays, gate-induced drain leakage (GIDL) current has been suggested as a solution to increase the string channel potential to trigger the erase operation. Thanks to that erase scheme, the memory array can be built directly on the top of a $$n^+$$ n + plate, without requiring any p-doped region to contact the string channel and therefore allowing to simplify the manufacturing process and increase the array integration density. For those reasons, the understanding of the physical phenomena occurring in the string when GIDL is triggered is important for the proper design of the cell structure and of the voltage waveforms adopted during erase. Even though a detailed comprehension of the GIDL phenomenology can be achieved by means of technology computer-aided design (TCAD) simulations, they are usually time and resource consuming, especially when realistic string structures with many word-lines (WLs) are considered. In this chapter, an analysis of the GIDL-assisted erase in 3–D VC nand memory arrays is presented. First, the evolution of the string potential and GIDL current during erase is investigated by means of TCAD simulations; then, a compact model able to reproduce both the string dynamics and the threshold voltage transients with reduced computational effort is presented. The developed compact model is proven to be a valuable tool for the optimization of the array performance during erase assisted by GIDL. Then, the idea of taking advantage of GIDL for the erase operation is exported to the context of spiking neural networks (SNNs) based on NOR Flash memory arrays, which require operational schemes that allow single-cell selectivity during both cell program and cell erase. To overcome the block erase typical of nor Flash memory arrays based on Fowler-Nordheim tunneling, a new erase scheme that triggers GIDL in the NOR Flash cell and exploits hot-hole injection (HHI) at its drain side to accomplish the erase operation is presented. Using that scheme, spike-timing dependent plasticity (STDP) is implemented in a mainstream NOR Flash array and array learning is successfully demonstrated in a prototype SNN. The achieved results represent an important step for the development of large-scale neuromorphic systems based on mature and reliable memory technologies.
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Yang, Yulong, and Shinya Ishii. "Serum Uric Acid and Biomarkers of Lumbar Spine Bone Mineral Density." In Biomarkers in Bone Disease, 201–20. Dordrecht: Springer Netherlands, 2017. http://dx.doi.org/10.1007/978-94-007-7693-7_1.

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Yang, Yulong, and Shinya Ishii. "Serum Uric Acid and Biomarkers of Lumbar Spine Bone Mineral Density." In Biomarkers in Bone Disease, 1–20. Dordrecht: Springer Netherlands, 2015. http://dx.doi.org/10.1007/978-94-007-7745-3_1-1.

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Wang, Zejun, and Henriette van Praag. "Exercise and the Brain: Neurogenesis, Synaptic Plasticity, Spine Density, and Angiogenesis." In Functional Neuroimaging in Exercise and Sport Sciences, 3–24. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-3293-7_1.

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Stoeter, P., and N. Prey. "Pulse-Synchronous Alterations of Contrast Density During Carotid Angiography." In Imaging of Brain Metabolism Spine and Cord Interventional Neuroradiology Free Communications, 649–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74337-5_186.

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Kato, Shuichi, Seiichi Sakatani, and Akira Hirose. "Influence of Dendritic Spine Morphology on Spatiotemporal Change of Calcium/Calmoduline-Dependent Protein Kinase Density." In Neural Information Processing, 31–36. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-30499-9_4.

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Conference papers on the topic "Spike density"

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Cheng, Li-Fang, Tung-Chien Chen, Nai-Fu Chang, and Liang-Gee Chen. "Density-based hardware-oriented classification for spike sorting microsystems." In 5th International IEEE/EMBS Conference on Neural Engineering (NER 2011). IEEE, 2011. http://dx.doi.org/10.1109/ner.2011.5910515.

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Jackel, David, Urs Frey, Michele Fiscella, and Andreas Hierlemann. "Blind source separation for spike sorting of high density microelectrode array recordings." In 5th International IEEE/EMBS Conference on Neural Engineering (NER 2011). IEEE, 2011. http://dx.doi.org/10.1109/ner.2011.5910476.

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Weingartner, Sebastian, Xiaomo Chen, Mehmet Akcakaya, and Tirin Moore. "Robust Online Spike Recovery for High-Density Electrode Recordings using Convolutional Compressed Sensing." In 2019 9th International IEEE/EMBS Conference on Neural Engineering (NER). IEEE, 2019. http://dx.doi.org/10.1109/ner.2019.8717072.

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Yang, Yuning, and Andrew J. Mason. "Optimization of nonlinear energy operator based spike detection circuit for high density neural recordings." In 2014 IEEE International Symposium on Circuits and Systems (ISCAS). IEEE, 2014. http://dx.doi.org/10.1109/iscas.2014.6865405.

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M. Kamboh, Awais, and Andrew J. Mason. "On-chip feature extraction for spike sorting in high density implantable neural recording systems." In 2010 IEEE Biomedical Circuits and Systems Conference (BioCAS 2010). IEEE, 2010. http://dx.doi.org/10.1109/biocas.2010.5709559.

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Jan, Sedivy, Frey Urs, Jackel David, and Hierlemann Andreas. "Independent-component-analysis-based spike sorting algorithm for high-density microelectrode array data processing." In 2009 IEEE Sensors. IEEE, 2009. http://dx.doi.org/10.1109/icsens.2009.5398244.

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Aoki, Takahiro, and Tadashi Tsubone. "Control of inter-spike-interval density of piecewise-constant chaotic spiking oscillator with dead-time." In 2011 European Conference on Circuit Theory and Design (ECCTD). IEEE, 2011. http://dx.doi.org/10.1109/ecctd.2011.6043330.

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Wouters, Jasper, Fabian Kloosterman, and Alexander Bertrand. "A data-driven regularization approach for template matching in spike sorting with high-density neural probes." In 2019 41st Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2019. http://dx.doi.org/10.1109/embc.2019.8856930.

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Ushakov, Y. V., A. A. Dubkov, and B. Spagnolo. "The resemblance of an autocorrelation function to a power spectrum density for a spike train of an auditory model." In PHYSICS, COMPUTATION, AND THE MIND - ADVANCES AND CHALLENGES AT INTERFACES: Proceedings of the 12th Granada Seminar on Computational and Statistical Physics. AIP, 2013. http://dx.doi.org/10.1063/1.4776515.

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Wouters, Jasper, Fabian Kloosterman, and Alexander Bertrand. "Data-Driven Multi-Channel Filter Design with Peak-Interference Suppression for Threshold-Based Spike Sorting in High-Density Neural Probes." In ICASSP 2018 - 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2018. http://dx.doi.org/10.1109/icassp.2018.8462517.

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Reports on the topic "Spike density"

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Varney, Elliot. A New Opportunistic Bone Density Screening Method Based on Colored CT Images of the Spine. Science Repository, May 2019. http://dx.doi.org/10.31487/j.rdi.2019.02.02.

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Mattingly, Margarita Claudia Krieghoff. Rapidity Density Fluctuations in Hadron-Nucleus Interactions: Spikes, Intermittency, and Fractal Properties of Multiple Production in Ag, Au, and Mg Targets with p, $\bar{p}$, and π- Projectiles at 100 and 320 GeV/c. Office of Scientific and Technical Information (OSTI), January 1991. http://dx.doi.org/10.2172/1127927.

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Fields, Michael J., Mordechai Shemesh, and Anna-Riitta Fuchs. Significance of Oxytocin and Oxytocin Receptors in Bovine Pregnancy. United States Department of Agriculture, August 1994. http://dx.doi.org/10.32747/1994.7568790.bard.

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Oxytocin has multiple actions in bovine reproductive tract and it was our purpose to determine the nature of these actions and their significance for the physiology of bovine reproduction. The bovine oxytocin receptors (OTR) gene was cloned and its expression studied during the cycle and pregnancy. OTR mRNA changed in parallel with OTR with control occurring mainly at the transcriptional level. However, the endocrine regulation of OTR were found in endometrium and cervical mucosa at estrus and at parturition. In both tissues OTR were suppressed in the luteal phase and early pregnancy. Whereas cervical OTR remained suppressed throughout pregnancy, endometrial OTR began to increase soon after implantation and reached higher concentrations in midpregnancy than at estrus. OTR in caruncles did not increase until third trimester, and OTR in cervical mucosa, cotyledons and fetal membranes increased only at term. Myometrial OTR showed less variation and OTR were present throughout the cycle and pregnancy but increased significantly during mid- and late pregnancy. OTR were localized in endometrial epithelial cells and lumina epithelial cells of cervical mucosa as determined by immunohistochemistry. Endometrial OTR were functional throughout pregnancy and mediated PGF release from day 50 onwards in a receptor density related manner. OTR in cervical mucosa mediated PGE release both in vivo and in vitro, as shown in cyclic cows. The ontogeny of uterine OTR was studied from third trimester fetal stage until puberty. OTR were present in endometrium and cervical mucosa in high concentrations throughout this period; myometrial OTR began to increase somewhat later but also reached adult values by 6-mo of age. In the prepuberal heifers OT injections failed to initiate PGF2a, release. The influence of steroids on the effect of OT was examined. Ovariectomy and E2 were without effect, but P4 with or without E2 induced a massive PGF2a release in response to OT in spite of reduced OTR. Bovine cyclooxygenases (COX-1 and COX-2) were cloned and their expression studied in the endometrium of prepuberal heifers and pregnant cows. Untreated and E2 treated prepuberal heifers did not express COX-2 but P4 treated heifers did express the mRNA for COX-2, albeit weakly. During the second half of pregnancy COX-2 mRNA was strongly expressed in cotyledons and somewhat less in caruncles, whereas endometrium, myometrium and cervical mucosa showed only weak, if any, COX-2 mRNA under basal conditions. However, 2 h after OT injection significant increases in COX-2 mRNA were found in endometrial RNA. Thus OT is capable of inducing the expression of the inducible COX-2 gene, and hence the conversion of arachidonic acid to prostanoids. The results indicate that the functions of OT are numerous and probably essential for successful pregnancy and parturition.
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Guy, Charles, Gozal Ben-Hayyim, Gloria Moore, Doron Holland, and Yuval Eshdat. Common Mechanisms of Response to the Stresses of High Salinity and Low Temperature and Genetic Mapping of Stress Tolerance Loci in Citrus. United States Department of Agriculture, May 1995. http://dx.doi.org/10.32747/1995.7613013.bard.

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The objectives that were outlined in our original proposal have largely been achieved or will be so by the end of the project in February 1995 with one exception; that of mapping cold tolerance loci based on the segregation of tolerance in the BC1 progeny population. Briefly, our goals were to 1) construct a densely populated linkage map of the citrus genome: 2) map loci important in cold and/or salt stress tolerance; and 3) characterize the expression of genes responsive to cold land salt stress. As can be seen by the preceding listing of accomplishments, our original objectives A and B have been realized, objective C has been partially tested, objective D has been completed, and work on objectives E and F will be completed by the end of 1995. Although we have yet to map any loci that contribute to an ability of citrus to maintain growth when irrigated with saline water, our very encouraging results from the 1993 experiment provides us with considerable hope that 1994's much more comprehensive and better controlled experiment will yield the desired results once the data has been fully analyzed. Part of our optimism derives from the findings that loci for growth are closely linked with loci associated with foliar Cl- and Na+ accumulation patterns under non-salinization conditions. In the 1994 experiment, if ion exclusion or sequestration traits are segregating in the population, the experimental design will permit their resolution. Our fortunes with respect to cold tolerance is another situation. In three attempts to quantitatively characterize cold tolerance as an LT50, the results have been too variable and the incremental differences between sensitive and tolerant too small to use for mapping. To adequately determine the LT50 requires many plants, many more than we have been able to generate in the time and space available by making cuttings from small greenhouse-grown stock plants. As it has turned out, with citrus, to prepare enough plants needed to be successful in this objective would have required extensive facilities for both growing and testing hardiness which simply were not available at University of Florida. The large populations necessary to overcome the variability we encountered was unanticipated and unforeseeable at the project's outset. In spite of the setbacks, this project, when it is finally complete will be exceedingly successful. Listing of Accomplishments During the funded interval we have accomplished the following objectives: Developed a reasonably high density linkage map for citrus - mapped the loci for two cold responsive genes that were cloned from Poncirus - mapped the loci for csa, the salt responsive gene for glutathione peroxidase, and ccr a circadian rhythm gene from citrus - identified loci that confer parental derived specific DNA methylation patterns in the Citrus X Poncirus cross - mapped 5 loci that determine shoot vigor - mapped 2 loci that influence leaf Na+ accumulation patterns under non-saline conditions in the BC1 population - mapped 3 loci that influence leaf Na+ accumulation paterns during salt sress - mapped 2 loci that control leaf Cl- accumulation patterns under non-saline conditions - mapped a locus that controls leaf Cl- accumulation patterns during salt stress Screened the BC1 population for growth reduction during salinization (controls and salinized), and cold tolerance - determined population variation for shoot/root ratio of Na+ and Cl- - determined levels for 12 inorganic nutrient elements in an effort to examine the influence of salinization on ion content with emphasis on foliar responses - collected data on ion distribution to reveal patterns of exclusion/sequestration/ accumulation - analyzed relationships between ion content and growth Characterization of gene expression in response to salt or cold stress - cloned the gene for the salt responsive protein csa, identified it as glutathione peroxidase, determined the potential target substrate from enzymatic studies - cloned two other genes responsive to salt stress, one for the citrus homologue of a Lea5, and the other for an "oleosin" like gene - cold regulated (cor) genes belonging to five hybridization classes were isolated from Poncirus, two belonged to the group 2 Lea superfamily of stress proteins, the others show no significant homology to other known sequences - the expression of csa during cold acclimation was examined, and the expression of some of the cor genes were examined in response to salt stress - the influence of salinization on cold tolerance has been examined with seedling populations - conducted protein blot studies for expression of cold stress proteins during salt stress and vice versa
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