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  1. Cortical modulation of short-latency TMS-evoked potentials

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    Domenica eVeniero

    2013-01-01

    Full Text Available Transcranial magnetic stimulation - electroencephalogram (TMS-EEG co-registration offers the opportunity to test reactivity of brain areas across distinct conditions through TMS-evoked potentials (TEPs. Several TEPs have been described, their functional meaning being largely unknown. In particular, short-latency potentials peaking at 5 (P5 and 8 (N8 ms after the TMS pulse have been recently described, but because of their huge amplitude, the problem of whether their origin is cortical or not has been opened. To gain information about these components, we employed a protocol that modulates primary motor cortex excitability (MI through an exclusively cortical phenomena: low frequency stimulation of premotor area (PMC. TMS was applied simultaneously with EEG recording from 70 electrodes. Amplitude of TEPs evoked by 200 single-pulses TMS delivered over MI at 110% of resting motor threshold was measured before and after applying 900 TMS conditioning stimuli to left premotor cortex with 1 Hz repetition rate. Single subject analyses showed reduction in TEPs amplitude after PMC conditioning in a sample of participants and increase in TEPs amplitude in two subjects. No effects were found on corticospinal excitability as recorded by motor evoked potentials (MEPs. Furthermore, correlation analysis showed an inverse relation between the effects of the conditioning protocol on P5-N8 complex amplitude and MEPs amplitude. Because the effects of the used protocol have been ascribed to a cortical interaction between premotor area and MI, we suggest that despite the sign of P5-N8 amplitude modulation is not consistent across participant, this modulation could indicate, at least in part, their cortical origin. We conclude that with an accurate experimental procedure early-latency components can be used to evaluate the reactivity of the stimulated cortex.

  2. Short-latency crossed responses in the human biceps femoris muscle

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    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre

    Ipsilateral knee (iKnee) joint rotations in seated humans elicit short-latency crossed spinal reflexes in the contralateral biceps femoris (cBF) muscle (Stevenson et al., 2012). The short-latency cBF reflexes were inhibitory following iKnee extension perturbations, and facilitatory following...

  3. Short latency compound action potentials from mammalian gravity receptor organs

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    Jones, T. A.; Jones, S. M.

    1999-01-01

    Gravity receptor function was characterized in four mammalian species using far-field vestibular evoked potentials (VsEPs). VsEPs are compound action potentials of the vestibular nerve and central relays that are elicited by linear acceleration ramps applied to the cranium. Rats, mice, guinea pigs, and gerbils were studied. In all species, response onset occurred within 1.5 ms of the stimulus onset. Responses persisted during intense (116 dBSPL) wide-band (50 to 50 inverted question mark omitted inverted question mark000 Hz) forward masking, whereas auditory responses to intense clicks (112 dBpeSPL) were eliminated under the same conditions. VsEPs remained after cochlear extirpation but were eliminated following bilateral labyrinthectomy. Responses included a series of positive and negative peaks that occurred within 8 ms of stimulus onset (range of means at +6 dBre: 1.0 g/ms: P1=908 to 1062 micros, N1=1342 to 1475 micros, P2=1632 to 1952 micros, N2=2038 to 2387 micros). Mean response amplitudes at +6 dBre: 1.0 g/ms ranged from 0.14 to 0.99 microV. VsEP input/output functions revealed latency slopes that varied across peaks and species ranging from -19 to -51 micros/dB. Amplitude-intensity slopes also varied ranging from 0.04 to 0.08 microV/dB for rats and mice. Latency values were comparable to those of birds although amplitudes were substantially smaller in mammals. VsEP threshold values were considerably higher in mammals compared to birds and ranged from -8.1 to -10.5 dBre 1.0 g/ms across species. These results support the hypothesis that mammalian gravity receptors are less sensitive to dynamic stimuli than are those of birds.

  4. The effect of water immersion on short-latency somatosensory evoked potentials in human

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    Sato Daisuke

    2012-01-01

    Full Text Available Abstract Background Water immersion therapy is used to treat a variety of cardiovascular, respiratory, and orthopedic conditions. It can also benefit some neurological patients, although little is known about the effects of water immersion on neural activity, including somatosensory processing. To this end, we examined the effect of water immersion on short-latency somatosensory evoked potentials (SEPs elicited by median nerve stimuli. Short-latency SEP recordings were obtained for ten healthy male volunteers at rest in or out of water at 30°C. Recordings were obtained from nine scalp electrodes according to the 10-20 system. The right median nerve at the wrist was electrically stimulated with the stimulus duration of 0.2 ms at 3 Hz. The intensity of the stimulus was fixed at approximately three times the sensory threshold. Results Water immersion significantly reduced the amplitudes of the short-latency SEP components P25 and P45 measured from electrodes over the parietal region and the P45 measured by central region. Conclusions Water immersion reduced short-latency SEP components known to originate in several cortical areas. Attenuation of short-latency SEPs suggests that water immersion influences the cortical processing of somatosensory inputs. Modulation of cortical processing may contribute to the beneficial effects of aquatic therapy. Trial Registration UMIN-CTR (UMIN000006492

  5. Increased threshold of short-latency motor evoked potentials in transgenic mice expressing Channelrhodopsin-2.

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    Wu, Wei; Xiong, Wenhui; Zhang, Ping; Chen, Lifang; Fang, Jianqiao; Shields, Christopher; Xu, Xiao-Ming; Jin, Xiaoming

    2017-01-01

    Transgenic mice that express channelrhodopsin-2 or its variants provide a powerful tool for optogenetic study of the nervous system. Previous studies have established that introducing such exogenous genes usually does not alter anatomical, electrophysiological, and behavioral properties of neurons in these mice. However, in a line of Thy1-ChR2-YFP transgenic mice (line 9, Jackson lab), we found that short-latency motor evoked potentials (MEPs) induced by transcranial magnetic stimulation had a longer latency and much lower amplitude than that of wild type mice. MEPs evoked by transcranial electrical stimulation also had a much higher threshold in ChR2 mice, although similar amplitudes could be evoked in both wild and ChR2 mice at maximal stimulation. In contrast, long-latency MEPs evoked by electrically stimulating the motor cortex were similar in amplitude and latency between wild type and ChR2 mice. Whole-cell patch clamp recordings from layer V pyramidal neurons of the motor cortex in ChR2 mice revealed no significant differences in intrinsic membrane properties and action potential firing in response to current injection. These data suggest that corticospinal tract is not accountable for the observed abnormality. Motor behavioral assessments including BMS score, rotarod, and grid-walking test showed no significant differences between the two groups. Because short-latency MEPs are known to involve brainstem reticulospinal tract, while long-latency MEPs mainly involve primary motor cortex and dorsal corticospinal tract, we conclude that this line of ChR2 transgenic mice has normal function of motor cortex and dorsal corticospinal tract, but reduced excitability and responsiveness of reticulospinal tracts. This abnormality needs to be taken into account when using these mice for related optogenetic study.

  6. Auditory brainstem, middle and late latency responses to short gaps in noise at different presentation rates.

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    Alhussaini, Khalid; Bohorquez, Jorge; Delgado, Rafael E; Ozdamar, Ozcan

    2018-01-29

    The effects of rate on auditory-evoked potentials (AEP) to short noise gaps (12 ms) recorded at high sampling rates using wide-band filters were investigated. Auditory brainstem (ABR), middle latency (MLR), late latency (LLR) and steady-state (ASSR) responses were simultaneously recorded in adult subjects at four gap rates (0.5, 1, 5 and 40 Hz). Major components (V, Na, Pa, Nb, Pb, N1 and P2) were identified at each rate and analysed for latency/amplitude characteristics. Gap responses at 40 Hz were recovered from Quasi-ASSRs (QASSR) using the CLAD deconvolution method. Fourteen right ears of young normal hearing subjects were tested. All major components were present in all subjects at 1 Hz. P1 (P50) appeared as a low-pass filtered component of Pa and Pb waves. At higher rates, N1 and P2 disappeared completely while major ABR-MLR components were identified. Peak latencies were mostly determined by noise onsets slightly delayed by offset responses. Major AEP components can be recorded to short gaps at 1 Hz using high sampling rates and wide-band filters. At higher rates, only ABR and MLRs can be recorded. Such simultaneous recordings may provide a complete assessment of temporal resolution and processing at different levels of auditory pathways.

  7. Toward Massive, Ultrareliable, and Low-Latency Wireless Communication With Short Packets

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    Durisi, Giuseppe; Koch, Tobias; Popovski, Petar

    2016-01-01

    that should be received with low latency and ultrahigh reliability. Current wireless systems are not designed to support short-packet transmissions. For example, the design of current systems relies on the assumption that the metadata (control information) is of negligible size compared to the actual...... information payload. Hence, transmitting metadata using heuristic methods does not affect the overall system performance. However, when the packets are short, metadata may be of the same size as the payload, and the conventional methods to transmit it may be highly suboptimal. In this paper, we review recent...

  8. Treating Excessively Slow Responding of a Young Man with Asperger Syndrome Using Differential Reinforcement of Short Response Latencies

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    Tiger, Jeffrey H.; Bouxsein, Kelly J.; Fisher, Wayne W.

    2007-01-01

    Fjellstedt and Sulzer-Azaroff (1973) used differential reinforcement of short latencies to decrease a child's latency to comply with instructions. We replicated this contingency with a young man diagnosed with Asperger syndrome across two tasks (question answering and math problem solving). We added a differential reinforcement contingency to…

  9. Short latency vestibular evoked potentials in the Japanese quail (Coturnix coturnix japonica)

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    Jones, S. M.; Jones, T. A.; Shukla, R.

    1997-01-01

    Short-latency vestibular-evoked potentials to pulsed linear acceleration were characterized in the quail. Responses occurred within 8 ms following the onset of stimuli and were composed of a series of positive and negative peaks. The latencies and amplitudes of the first four peaks were quantitatively characterized. Mean latencies at 1.0 g ms-1 ranged from 1265 +/- 208 microseconds (P1, N = 18) to 4802 +/- 441 microseconds (N4, N = 13). Amplitudes ranged from 3.72 +/- 1.51 microV (P1/N1, N = 18) to 1.49 +/- 0.77 microV (P3/N3, N = 16). Latency-intensity (LI) slopes ranged from -38.7 +/- 7.3 microseconds dB-1 (P1, N = 18) to -71.6 +/- 21.9 microseconds dB-1 (N3, N = 15) and amplitude-intensity (AI) slopes ranged from 0.20 +/- 0.08 microV dB-1 (P1/N1, N = 18) to 0.07 +/- 0.04 microV dB-1 (P3/N3, N = 11). The mean response threshold across all animals was -21.83 +/- 3.34 dB re: 1.0 g ms-1 (N = 18). Responses remained after cochlear extirpation showing that they could not depend critically on cochlear activity. Responses were eliminated by destruction of the vestibular end organs, thus showing that responses depended critically and specifically on the vestibular system. The results demonstrate that the responses are vestibular and the findings provide a scientific basis for using vestibular responses to evaluate vestibular function through ontogeny and senescence in the quail.

  10. Short-latency crossed responses in the human biceps femoris muscle

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    Stevenson, Andrew J T; Kamavuako, Ernest N; Geertsen, Svend Sparre

    2015-01-01

    fast for a transcortical pathway to contribute. The cBF inhibitory and facilitatory reflexes followed the automatic gain control principle, with the size of the response increasing as the level of background pre-contraction in the cBF muscle increased. In addition to the surface EMG, both short...... pathways (likely involving commissural interneurons) from ipsilateral afferents to common motoneurons in the contralateral leg can likely explain the perturbation direction-dependent reversal in the sign of the short-latency cBF reflex. This article is protected by copyright. All rights reserved.......Interlimb reflexes contribute to the central neural coordination between different limbs in both humans and animals. Although commissural interneurons have only been directly identified in animals, spinally mediated interlimb reflexes have been discovered in a number of human lower limb muscles...

  11. Topographic prominence discriminator for the detection of short-latency spikes of retinal ganglion cells

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    Choi, Myoung-Hwan; Ahn, Jungryul; Park, Dae Jin; Lee, Sang Min; Kim, Kwangsoo; Cho, Dong-il Dan; Senok, Solomon S.; Koo, Kyo-in; Goo, Yong Sook

    2017-02-01

    Objective. Direct stimulation of retinal ganglion cells in degenerate retinas by implanting epi-retinal prostheses is a recognized strategy for restoration of visual perception in patients with retinitis pigmentosa or age-related macular degeneration. Elucidating the best stimulus-response paradigms in the laboratory using multielectrode arrays (MEA) is complicated by the fact that the short-latency spikes (within 10 ms) elicited by direct retinal ganglion cell (RGC) stimulation are obscured by the stimulus artifact which is generated by the electrical stimulator. Approach. We developed an artifact subtraction algorithm based on topographic prominence discrimination, wherein the duration of prominences within the stimulus artifact is used as a strategy for identifying the artifact for subtraction and clarifying the obfuscated spikes which are then quantified using standard thresholding. Main results. We found that the prominence discrimination based filters perform creditably in simulation conditions by successfully isolating randomly inserted spikes in the presence of simple and even complex residual artifacts. We also show that the algorithm successfully isolated short-latency spikes in an MEA-based recording from degenerate mouse retinas, where the amplitude and frequency characteristics of the stimulus artifact vary according to the distance of the recording electrode from the stimulating electrode. By ROC analysis of false positive and false negative first spike detection rates in a dataset of one hundred and eight RGCs from four retinal patches, we found that the performance of our algorithm is comparable to that of a generally-used artifact subtraction filter algorithm which uses a strategy of local polynomial approximation (SALPA). Significance. We conclude that the application of topographic prominence discrimination is a valid and useful method for subtraction of stimulation artifacts with variable amplitudes and shapes. We propose that our algorithm

  12. Triceps surae short latency stretch reflexes contribute to ankle stiffness regulation during human running.

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    Neil J Cronin

    Full Text Available During human running, short latency stretch reflexes (SLRs are elicited in the triceps surae muscles, but the function of these responses is still a matter of controversy. As the SLR is primarily mediated by Ia afferent nerve fibres, various methods have been used to examine SLR function by selectively blocking the Ia pathway in seated, standing and walking paradigms, but stretch reflex function has not been examined in detail during running. The purpose of this study was to examine triceps surae SLR function at different running speeds using Achilles tendon vibration to modify SLR size. Ten healthy participants ran on an instrumented treadmill at speeds between 7 and 15 km/h under 2 Achilles tendon vibration conditions: no vibration and 90 Hz vibration. Surface EMG from the triceps surae and tibialis anterior muscles, and 3D lower limb kinematics and ground reaction forces were simultaneously collected. In response to vibration, the SLR was depressed in the triceps surae muscles at all speeds. This coincided with short-lasting yielding at the ankle joint at speeds between 7 and 12 km/h, suggesting that the SLR contributes to muscle stiffness regulation by minimising ankle yielding during the early contact phase of running. Furthermore, at the fastest speed of 15 km/h, the SLR was still depressed by vibration in all muscles but yielding was no longer evident. This finding suggests that the SLR has greater functional importance at slow to intermediate running speeds than at faster speeds.

  13. THE PARABRACHIAL NUCLEUS IS A CRITICAL LINK IN THE TRANSMISSION OF SHORT LATENCY NOCICEPTIVE INFORMATION TO MIDBRAIN DOPAMINERGIC NEURONS

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    Coizet, V.; Dommett, E. J.; Klop, E. M.; Redgrave, P.; Overton, P. G.

    2010-01-01

    Many dopaminergic neurons exhibit a short-latency response to noxious stimuli, the source of which is unknown. Here we report that the nociceptive-recipient parabrachial nucleus appears to be a critical link in the transmission of pain related information to dopaminergic neurons. Injections of

  14. Possible anatomical pathways for short-latency multisensory integration processes in primary sensory cortices.

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    Henschke, Julia U; Noesselt, Tömme; Scheich, Henning; Budinger, Eike

    2015-03-01

    Multisensory integration does not only recruit higher-level association cortex, but also low-level and even primary sensory cortices. Here, we will describe and quantify two types of anatomical pathways, a thalamocortical and a corticocortical that possibly underlie short-latency multisensory integration processes in the primary auditory (A1), somatosensory (S1), and visual cortex (V1). Results were obtained from Mongolian gerbils, a common model-species in neuroscience, using simultaneous injections of different retrograde tracers into A1, S1, and V1. Several auditory, visual, and somatosensory thalamic nuclei project not only to the primary sensory area of their own (matched) but also to areas of other (non-matched) modalities. The crossmodal output ratios of these nuclei, belonging to both core and non-core sensory pathways, vary between 0.4 and 63.5 % of the labeled neurons. Approximately 0.3 % of the sensory thalamic input to A1, 5.0 % to S1, and 2.1 % to V1 arise from non-matched nuclei. V1 has most crossmodal corticocortical connections, projecting strongest to S1 and receiving a similar amount of moderate inputs from A1 and S1. S1 is mainly interconnected with V1. A1 has slightly more projections to V1 than S1, but gets just faint inputs from there. Concerning the layer-specific distribution of the retrogradely labeled somata in cortex, V1 provides the most pronounced feedforward-type outputs and receives (together with S1) most pronounced feedback-type inputs. In contrast, A1 has most pronounced feedback-type outputs and feedforward-type inputs in this network. Functionally, the different sets of thalamocortical and corticocortical connections could underlie distinctive types of integration mechanisms for different modality pairings.

  15. Spatial task context makes short-latency reaches prone to induced Roelofs illusion

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    Bahareh eTaghizadeh

    2014-08-01

    Full Text Available The perceptual localization of an object is often more prone to illusions than an immediate visuomotor action towards that object. The induced Roelofs effect (IRE probes the illusory influence of task-irrelevant visual contextual stimuli on the processing of task-relevant visuospatial instructions during movement preparation. In the IRE, the position of a task-irrelevant visual object induces a shift in the localization of a visual target when subjects indicate the position of the target by verbal response, key-presses or delayed pointing to the target (‘perception’ tasks, but not when immediately pointing or reaching towards it without instructed delay (‘action’ tasks. This discrepancy was taken as evidence for the dual-visual-stream or perception-action hypothesis, but was later explained by a phasic distortion of the egocentric spatial reference frame which is centered on subjective straight-ahead and used for reach planning. Both explanations critically depend on delayed movements to explain the IRE for action tasks. Here we ask: first, if the IRE can be observed for short-latency reaches; second, if the IRE in fact depends on a distorted egocentric frame of reference. Human subjects were tested in new versions of the IRE task in which the reach goal had to be localized with respect to another object, i.e., in an allocentric reference frame. First, we found an IRE even for immediate reaches in our allocentric task, but not for an otherwise similar egocentric control task. Second, the IRE depended on the position of the task-irrelevant frame relative to the reference object, not relative to subjective straight-ahead. We conclude that the IRE for reaching does not mandatorily depend on prolonged response delays, nor does it depend on motor planning in an egocentric reference frame. Instead, allocentric encoding of a movement goal is sufficient to make immediate reaches susceptible to IRE, underlining the context dependence of

  16. Group Ia afferents likely contribute to short-latency interlimb reflexes in the human biceps femoris muscle

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    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre

    2017-01-01

    amplitudes (4 vs. 8°) at the same 150°/s velocity (p’s > 0.08). Conclusion: Because fast conducting group Ia muscle spindle afferents are sensitive to changes in muscle stretch velocity, while group II spindle afferents are sensitive to changes in amplitude (Grey et al., JPhysiol., 2001; Matthews, Trends...... Neurosci., 1991), group Ia velocity sensitive muscle spindle afferents likely contribute to the short-latency crossed spinal reflexes in the cBF muscle following iKnee joint rotations. This supports the findings for the short-latency crossed responses in the human soleus muscle (Stubbs & Mrachacz...... neurons in humans, with primary contributions from group Ia muscle spindle afferents....

  17. Short-term pressure induced suppression of the short-latency response: a new methodology for investigating stretch reflexes

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    Leukel, Christian; Lundbye-Jensen, Jesper; Gruber, Markus

    2009-01-01

    application in more detail. Fifty-eight healthy subjects were divided into seven protocols. Unilateral stretches were applied to the calf muscles to elicit a SLR, and bilateral stretches to evoke a subsequent medium-latency response (MLR). Furthermore, H-reflexes and sensory nerve action potentials (SNAPs......, the introduced method can be a useful tool to study afferent feedback in motor control....

  18. [The use of short-latency auditory evoked potentials in the diagnosis of acoustic neurinomas].

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    Baliazin, V A; Bakhtin, O M; Bu Khaled, Kh E; Filatova, V S

    1993-01-01

    The short-latent acoustic evoked potentials in patients with unilateral neurosensory hypoacusis due to the tumor of the acoustic nerve or other etiology were recorded. It was found that the patients had no potential in the diseased area in monaural sound stimulation, but binaural sound stimulation enabled these potentials to be recorded. With this, the short-latent acoustic evoked potentials in patients with verified neurinoma showed a reduction in the third wave to the point of its disappearance. Those in patients whose neurosensory hypoacusis were unassociated with the development of neoplasms in the area of the acoustic nerve involve the third wave whose magnitude did not differ from that recorded in the examinees with otologically normal hearing. The authors propose to measure the third wave of the short-latent acoustic evoked potential recorded in binaural sound stimulation as a possible screening of persons at a high risk for neurinoma among patients with unilateral neurosensory hypoacusis.

  19. Origin and function of short-latency inputs to the neural substrates underlying the acoustic startle reflex

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    Ricardo eGómez-Nieto

    2014-07-01

    Full Text Available The acoustic startle reflex (ASR is a survival mechanism of alarm, which rapidly alerts the organism to a sudden loud auditory stimulus. In rats, the primary ASR circuit encompasses three serially connected structures: cochlear root neurons (CRNs, neurons in the caudal pontine reticular nucleus (PnC, and motoneurons in the medulla and spinal cord. It is well established that both CRNs and PnC neurons receive short-latency auditory inputs to mediate the ASR. Here, we investigated the anatomical origin and functional role of these inputs using a multidisciplinary approach that combines morphological, electrophysiological and behavioural techniques. Anterograde tracer injections into the cochlea suggest that CRNs somata and dendrites receive inputs depending, respectively, on their basal or apical cochlear origin. Confocal colocalization experiments demonstrated that these cochlear inputs are immunopositive for the vesicular glutamate transporter 1. Using extracellular recordings in vivo followed by subsequent tracer injections, we investigated the response of PnC neurons after contra-, ipsi-, and bilateral acoustic stimulation and identified the source of their auditory afferents. Our results showed that the binaural firing rate of PnC neurons was higher than the monaural, exhibiting higher spike discharges with contralateral than ipsilateral acoustic stimulations. Our histological analysis confirmed the CRNs as the principal source of short-latency acoustic inputs, and indicated that other areas of the cochlear nucleus complex are not likely to innervate PnC. Behaviourally, we observed a strong reduction of ASR amplitude in monaural earplugged rats that corresponds with the binaural summation process shown in our electrophysiological findings. Our study contributes to understand better the role of neuronal mechanisms in auditory alerting behaviours and provides strong evidence that the CRNs-PnC pathway mediates fast neurotransmission and binaural

  20. Short-latency stretch reflexes do not contribute to premature calf muscle activity during the stance phase of gait in spastic patients

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    Niet, M. de; Latour, H.; Hendricks, H.T.; Geurts, A.C.H.; Weerdesteijn, V.G.M.

    2011-01-01

    de Niet M, Latour H, Hendricks H, Geurts AC, Weerdesteyn V. Short-latency stretch reflexes do not contribute to premature calf muscle activity during the stance phase of gait in spastic patients. OBJECTIVE: To identify whether a relationship exists between stretch and activity of the calf muscles

  1. Clustered, regularly interspaced short palindromic repeat (CRISPR) diversity and virulence factor distribution in avian Escherichia coli.

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    Fu, Qiang; Su, Zhixin; Cheng, Yuqiang; Wang, Zhaofei; Li, Shiyu; Wang, Heng'an; Sun, Jianhe; Yan, Yaxian

    In order to investigate the diverse characteristics of clustered, regularly interspaced short palindromic repeat (CRISPR) arrays and the distribution of virulence factor genes in avian Escherichia coli, 80 E. coli isolates obtained from chickens with avian pathogenic E. coli (APEC) or avian fecal commensal E. coli (AFEC) were identified. Using the multiplex polymerase chain reaction (PCR), five genes were subjected to phylogenetic typing and examined for CRISPR arrays to study genetic relatedness among the strains. The strains were further analyzed for CRISPR loci and virulence factor genes to determine a possible association between their CRISPR elements and their potential virulence. The strains were divided into five phylogenetic groups: A, B1, B2, D and E. It was confirmed that two types of CRISPR arrays, CRISPR1 and CRISPR2, which contain up to 246 distinct spacers, were amplified in most of the strains. Further classification of the isolates was achieved by sorting them into nine CRISPR clusters based on their spacer profiles, which indicates a candidate typing method for E. coli. Several significant differences in invasion-associated gene distribution were found between the APEC isolates and the AFEC isolates. Our results identified the distribution of 11 virulence genes and CRISPR diversity in 80 strains. It was demonstrated that, with the exception of iucD and aslA, there was no sharp demarcation in the gene distribution between the pathogenic (APEC) and commensal (AFEC) strains, while the total number of indicated CRISPR spacers may have a positive correlation with the potential pathogenicity of the E. coli isolates. Copyright © 2016. Published by Elsevier Masson SAS.

  2. Factors Influencing Short-term Synaptic Plasticity in the Avian Cochlear Nucleus Magnocellularis

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    Jason Tait Sanchez Quinones

    2015-01-01

    Full Text Available Defined as reduced neural responses during high rates of activity, synaptic depression is a form of short-term plasticity important for the temporal filtering of sound. In the avian cochlear nucleus magnocellularis (NM, an auditory brainstem structure, mechanisms regulating short-term synaptic depression include pre-, post-, and extrasynaptic factors. Using varied paired-pulse stimulus intervals, we found that the time course of synaptic depression lasts up to four seconds at late-developing NM synapses. Synaptic depression was largely reliant on exogenous Ca 2+ -dependent probability of presynaptic neurotransmitter release, and to a lesser extent, on the desensitization of postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptor (AMPA-R. Interestingly, although extrasynaptic glutamate clearance did not play a significant role in regulating synaptic depression, blocking glutamate clearance at early-developing synapses altered synaptic dynamics, changing responses from depression to facilitation. These results suggest a developmental shift in the relative reliance on pre-, post-, and extrasynaptic factors in regulating short-term synaptic plasticity in NM.

  3. Thermal latency adds to lesion depth after application of high-power short-duration radiofrequency energy: Results of a computer-modeling study.

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    Irastorza, Ramiro M; d'Avila, Andre; Berjano, Enrique

    2018-02-01

    The use of ultra-short RF pulses could achieve greater lesion depth immediately after the application of the pulse due to thermal latency. A computer model of irrigated-catheter RF ablation was built to study the impact of thermal latency on the lesion depth. The results showed that the shorter the RF pulse duration (keeping energy constant), the greater the lesion depth during the cooling phase. For instance, after a 10-second pulse, lesion depth grew from 2.05 mm at the end of the pulse to 2.39 mm (17%), while after an ultra-short RF pulse of only 1 second the extra growth was 37% (from 2.22 to 3.05 mm). Importantly, short applications resulted in deeper lesions than long applications (3.05 mm vs. 2.39 mm, for 1- and 10-second pulse, respectively). While shortening the pulse duration produced deeper lesions, the associated increase in applied voltage caused overheating in the tissue: temperatures around 100 °C were reached at a depth of 1 mm in the case of 1- and 5-second pulses. However, since the lesion depth increased during the cooling period, lower values of applied voltage could be applied in short durations in order to obtain lesion depths similar to those in longer durations while avoiding overheating. The thermal latency phenomenon seems to be the cause of significantly greater lesion depth after short-duration high-power RF pulses. Balancing the applied total energy when the voltage and duration are changed is not the optimal strategy since short pulses can also cause overheating. © 2017 Wiley Periodicals, Inc.

  4. Individual differences in sound-in-noise perception are related to the strength of short-latency neural responses to noise.

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    Ekaterina Vinnik

    2011-02-01

    Full Text Available Important sounds can be easily missed or misidentified in the presence of extraneous noise. We describe an auditory illusion in which a continuous ongoing tone becomes inaudible during a brief, non-masking noise burst more than one octave away, which is unexpected given the frequency resolution of human hearing. Participants strongly susceptible to this illusory discontinuity did not perceive illusory auditory continuity (in which a sound subjectively continues during a burst of masking noise when the noises were short, yet did so at longer noise durations. Participants who were not prone to illusory discontinuity showed robust early electroencephalographic responses at 40-66 ms after noise burst onset, whereas those prone to the illusion lacked these early responses. These data suggest that short-latency neural responses to auditory scene components reflect subsequent individual differences in the parsing of auditory scenes.

  5. Short-latency stretch reflexes do not contribute to premature calf muscle activity during the stance phase of gait in spastic patients.

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    de Niet, Mark; Latour, Hilde; Hendricks, Henk; Geurts, Alexander C; Weerdesteyn, Vivian

    2011-11-01

    To identify whether a relationship exists between stretch and activity of the calf muscles during the stance phase of gait in patients with upper motor neuron syndrome (UMNS), while taking into account the physiologic phase shift between these entities. Survey. Ambulatory care and general community. Patients with UMNS (n=15; 9 patients with stroke, 6 patients with hereditary spastic paraparesis) with premature calf muscle activity during the stance phase of gait and healthy controls (n=13). Not applicable. Timing of optimal association (phase shift) between the lengthening velocity of the gastrocnemius muscle and its electromyographic activity as revealed by cross-correlation analyses. Although premature calf muscle activity was evident in the patient groups, the phase shift between calf muscle stretch and its activity did not correspond with the monosynaptic stretch reflex latency (40- to 80-ms time window). However, there was a main effect of group on the phase shifts (F(3,33)=3.23, P=.035). Post hoc analysis revealed that in the paretic leg of stroke patients, the electromyographic activity preceded the lengthening velocity by 9 ± 54ms, whereas in the control group, the electromyographic activity followed the pattern of the muscle-lengthening velocity with a delay of 61 ± 54ms (P=.029). Short-latency stretch reflexes do not significantly contribute to premature calf muscle activity in the stance phase of (spastic) gait. This notion questions the validity of the clinical assessment of hyperreflexia and clonus of the calf as a predictor of calf muscle spasticity during gait. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  6. The Short Isoform of BRD4 Promotes HIV-1 Latency by Engaging Repressive SWI/SNF Chromatin-Remodeling Complexes.

    Science.gov (United States)

    Conrad, Ryan J; Fozouni, Parinaz; Thomas, Sean; Sy, Hendrik; Zhang, Qiang; Zhou, Ming-Ming; Ott, Melanie

    2017-09-21

    BET proteins commonly activate cellular gene expression, yet inhibiting their recruitment paradoxically reactivates latent HIV-1 transcription. Here we identify the short isoform of BET family member BRD4 (BRD4S) as a corepressor of HIV-1 transcription. We found that BRD4S was enriched in chromatin fractions of latently infected T cells, and it was more rapidly displaced from chromatin upon BET inhibition than the long isoform. BET inhibition induced marked nucleosome remodeling at the latent HIV-1 promoter, which was dependent on the activity of BRG1-associated factors (BAF), an SWI/SNF chromatin-remodeling complex with known repressive functions in HIV-1 transcription. BRD4S directly bound BRG1, a catalytic subunit of BAF, via its bromodomain and extraterminal (ET) domain, and this isoform was necessary for BRG1 recruitment to latent HIV-1 chromatin. Using chromatin immunoprecipitation sequencing (ChIP-seq) combined with assay for transposase-accessible chromatin coupled to high-throughput sequencing (ATAC-seq) data, we found that the latent HIV-1 promoter phenotypically resembles endogenous long terminal repeat (LTR) sequences, pointing to a select role of BRD4S-BRG1 complexes in genomic silencing of invasive retroelements. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Reduced Short-Latency Afferent Inhibition in Prefrontal but not Motor Cortex and Its Association With Executive Function in Schizophrenia: A Combined TMS-EEG Study.

    Science.gov (United States)

    Noda, Yoshihiro; Barr, Mera S; Zomorrodi, Reza; Cash, Robin F H; Rajji, Tarek K; Farzan, Faranak; Chen, Robert; George, Tony P; Daskalakis, Zafiris J; Blumberger, Daniel M

    2018-01-13

    Cholinergic dysfunction is increasingly assumed to be involved in the pathophysiology of schizophrenia. Short-latency afferent inhibition (SAI) is a transcranial magnetic stimulation (TMS) paradigm that has been shown to assay central cholinergic activity from the motor cortex (M1). Recently, we established a method to index SAI from the dorsolateral prefrontal cortex (DLPFC), an area implicated in the pathophysiology of schizophrenia. We investigated SAI in M1 and DLPFC in schizophrenia. We hypothesized that modulation of N100 on TMS-evoked potentials (TEPs) from the DLPFC would be attenuated in patients with schizophrenia compared to healthy controls. SAI was examined in 12 patients, whose age was matched to controls, using TMS combined with electroencephalography (EEG). SAI was recorded with TMS applied to left M1 (M1-SAI) and DLPFC (DLPFC-SAI). For group comparison, we used the SAI data of healthy participants in our previous study. In patients, N100 TEP was significantly attenuated with DLPFC-SAI, whereas P180 TEP was significantly increased with M1-SAI. Between patients and controls, there were significant differences in modulation of P180 TEP by M1-SAI (t22 = -2.748, P = .012; patients > controls) and N100 TEP by DLPFC-SAI (t22 = 5.456, P < .0001; patients < controls). Further, modulation of N100 TEP by DLPFC-SAI significantly correlated with executive function (r = -.740, P = .006, N = 12). Our findings suggest that DLPFC-SAI but not M1-SAI were reduced in patients with schizophrenia and this was linked to deficits in cognition. This may reflect prefrontal cholinergic deficits and represent a biomarker for cholinergic and executive dysfunction in patients with schizophrenia. © The Author(s) 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Avian Influenza.

    Science.gov (United States)

    Zeitlin, Gary Adam; Maslow, Melanie Jane

    2005-05-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur.

  9. Feline immunodeficiency virus latency

    Science.gov (United States)

    2013-01-01

    Despite highly effective anti-retroviral therapy, HIV is thought to persist in patients within long-lived cellular reservoirs in the form of a transcriptionally inactive (latent) integrated provirus. Lentiviral latency has therefore come to the forefront of the discussion on the possibility of a cure for HIV infection in humans. Animal models of lentiviral latency provide an essential tool to study mechanisms of latency and therapeutic manipulation. Of the three animal models that have been described, the feline immunodeficiency virus (FIV)-infected cat is the most recent and least characterized. However, several aspects of this model make it attractive for latency research, and it may be complementary to other model systems. This article reviews what is known about FIV latency and chronic FIV infection and how it compares with that of other lentiviruses. It thereby offers a framework for the usefulness of this model in future research aimed at lentiviral eradication. PMID:23829177

  10. Avian anemia's

    Directory of Open Access Journals (Sweden)

    Raukar Jelena

    2005-01-01

    Full Text Available This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematological parameters for every single avian species.

  11. Telemetry System Data Latency

    Science.gov (United States)

    2017-07-13

    Two of the scenarios utilized the Windows Operating System on the GSSrs to broadcast the Chapter 10 data with different settings for buffer sizes...412TW-PA-17485 Telemetry System Data Latency. Jon Morgan AIR FORCE TEST CENTER EDWARDS AFB, CA 13 July 2017 4...Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202

  12. Avian anemia's

    OpenAIRE

    Raukar Jelena

    2005-01-01

    This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematologica...

  13. Chicken MDA5 senses short double-stranded RNA with implications for antiviral response against avian influenza viruses in chicken.

    Science.gov (United States)

    Hayashi, Tsuyoshi; Watanabe, Chiaki; Suzuki, Yasushi; Tanikawa, Taichiro; Uchida, Yuko; Saito, Takehiko

    2014-01-01

    Mammalian melanoma differentiation-associated gene-5 (MDA5) and retinoic acid-inducible gene-I (RIG-I) selectively sense double-stranded RNA (dsRNA) according to length, as well as various RNA viruses to induce an antiviral response. RIG-I, which plays a predominant role in the induction of antiviral responses against influenza virus infection, has been considered to be lacking in chicken, putting the function of chicken MDA5 (chMDA5) under the spotlight. Here, we show that chMDA5, unlike mammalian MDA5, preferentially senses shorter dsRNA synthetic analogues, poly(I:C), in chicken DF-1 fibroblasts. A requirement for caspase activation and recruitment domains for chMDA5-mediated chicken interferon beta (chIFNβ) induction and its interaction with mitochondrial antiviral signaling proteins were demonstrated. We also found that chMDA5 is involved in chIFNβ induction against avian influenza virus infection. Our findings imply that chMDA5 compensates in part the function of RIG-I in chicken, and highlights the importance of chMDA5 in the innate immune response in chicken. © 2013 S. Karger AG, Basel.

  14. Avian Metapneumoviruses

    Science.gov (United States)

    Avian metapneumovirus (aMPV) is an economically important virus that is the primary causal agent of turkey rhinotracheitis (TRT), also known as avian rhinotracheitis (ART). The virus causes an acute highly contagious infection of the upper respiratory tract in turkeys and was first isolated from tur...

  15. Avian Biotechnology.

    Science.gov (United States)

    Nakamura, Yoshiaki

    2017-01-01

    Primordial germ cells (PGCs) generate new individuals through differentiation, maturation and fertilization. This means that the manipulation of PGCs is directly linked to the manipulation of individuals, making PGCs attractive target cells in the animal biotechnology field. A unique biological property of avian PGCs is that they circulate temporarily in the vasculature during early development, and this allows us to access and manipulate avian germ lines. Following the development of a technique for transplantation, PGCs have become central to avian biotechnology, in contrast to the use of embryo manipulation and subsequent transfer to foster mothers, as in mammalian biotechnology. Today, avian PGC transplantation combined with recent advanced manipulation techniques, including cell purification, cryopreservation, depletion, and long-term culture in vitro, have enabled the establishment of genetically modified poultry lines and ex-situ conservation of poultry genetic resources. This chapter introduces the principles, history, and procedures of producing avian germline chimeras by transplantation of PGCs, and the current status of avian germline modification as well as germplasm cryopreservation. Other fundamental avian reproductive technologies are described, including artificial insemination and embryo culture, and perspectives of industrial applications in agriculture and pharmacy are considered, including poultry productivity improvement, egg modification, disease resistance impairment and poultry gene "pharming" as well as gene banking.

  16. Avian influenza

    Science.gov (United States)

    ... develop flu-like symptoms within 10 days of handling infected birds or being in an area with ... your provider if you become sick after you return from your trip. Current information regarding avian flu ...

  17. Avian Flu

    International Nuclear Information System (INIS)

    Eckburg, Paul

    2006-01-01

    Since 2003, a severe form of H5N1 avian influenza has rapidly spread throughout Asia and Europe, infecting over 200 humans in 10 countries. The spread of H5N1 virus from person-to-person has been rare, thus preventing the emergence of a widespread pandemic. However, this ongoing epidemic continues to pose an important public health threat. Avian flu and its pandemic potential in humans will be discussed.

  18. Long Latency Auditory Evoked Potentials during Meditation.

    Science.gov (United States)

    Telles, Shirley; Deepeshwar, Singh; Naveen, Kalkuni Visweswaraiah; Pailoor, Subramanya

    2015-10-01

    The auditory sensory pathway has been studied in meditators, using midlatency and short latency auditory evoked potentials. The present study evaluated long latency auditory evoked potentials (LLAEPs) during meditation. Sixty male participants, aged between 18 and 31 years (group mean±SD, 20.5±3.8 years), were assessed in 4 mental states based on descriptions in the traditional texts. They were (a) random thinking, (b) nonmeditative focusing, (c) meditative focusing, and (d) meditation. The order of the sessions was randomly assigned. The LLAEP components studied were P1 (40-60 ms), N1 (75-115 ms), P2 (120-180 ms), and N2 (180-280 ms). For each component, the peak amplitude and peak latency were measured from the prestimulus baseline. There was significant decrease in the peak latency of the P2 component during and after meditation (Pmeditation facilitates the processing of information in the auditory association cortex, whereas the number of neurons recruited was smaller in random thinking and non-meditative focused thinking, at the level of the secondary auditory cortex, auditory association cortex and anterior cingulate cortex. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  19. Unsupervised, low latency

    Directory of Open Access Journals (Sweden)

    Jayaram Raghuram

    2014-07-01

    Full Text Available We propose a method for detecting anomalous domain names, with focus on algorithmically generated domain names which are frequently associated with malicious activities such as fast flux service networks, particularly for bot networks (or botnets, malware, and phishing. Our method is based on learning a (null hypothesis probability model based on a large set of domain names that have been white listed by some reliable authority. Since these names are mostly assigned by humans, they are pronounceable, and tend to have a distribution of characters, words, word lengths, and number of words that are typical of some language (mostly English, and often consist of words drawn from a known lexicon. On the other hand, in the present day scenario, algorithmically generated domain names typically have distributions that are quite different from that of human-created domain names. We propose a fully generative model for the probability distribution of benign (white listed domain names which can be used in an anomaly detection setting for identifying putative algorithmically generated domain names. Unlike other methods, our approach can make detections without considering any additional (latency producing information sources, often used to detect fast flux activity. Experiments on a publicly available, large data set of domain names associated with fast flux service networks show encouraging results, relative to several baseline methods, with higher detection rates and low false positive rates.

  20. Spatiotemporal variation in avian diversity and the short-term effects of typhoons in tropical reef-karst forests on Taiwan.

    Science.gov (United States)

    Lee, Ya-Fu; Kuo, Yen-Min; Lin, Yu-Hsiu; Chu, Wen-Chen; Wu, Shu-Hui; Wang, Hsiang-Hua; Chao, Jung-Tai

    2008-06-01

    The diversity and spatiotemporal variation of avifauna in different settings of tropical coral reef-karst forests on the Hengchun Peninsula, Taiwan, were examined. The short-term effects on bird assemblages following two typhoons that severely impacted Hengchun were investigated. Line-transect census recorded 46 species of birds, dominated by forest-associated gleaning insectivores or omnivores, and 13% of the endemics of Taiwan. Prior to the typhoons, the continuous-canopy forest was close to the open forest setting in species evenness, but the species heterogeneity was lower and more variable. The continuous-canopy and open forests differed in overall avian composition, whereas two continuous-canopy forest settings were similar in composition. Typhoons did not significantly lower the mean numbers of either species or birds, nor affect the pattern of their spatial distribution in the forest settings. However, they did increase similarities in the species composition between the open and continuous-canopy settings, and caused a decrease in the similarity between forest edges and interiors. Overall, typhoons affected species composition more in the continuous-canopy forests than in the open setting, and more in interiors than in forest edges. This pattern corresponded to an increase in the species heterogeneity and species evenness in the forest interiors, indicating movements of birds from the edge toward the interior. Among different functional groups, gleaning omnivores tended to retain a pattern of higher abundance in the open forest setting than in the continuous-canopy forests, whereas the abundances of gleaning insectivores and cavity-nesting frugivores tended to decline in the latter or both settings.

  1. Short-term effects of avian predation variation on population size and local survival of the multimammate rat, Mastomys natalensis (Rodentia, Muridae)

    DEFF Research Database (Denmark)

    Gulck, T. van; Stocks, R.; Verhagen, Ron

    1998-01-01

    The influence of avian predation on population size and local survival of Mastomys natalensis rats in Tanzania was studied in a capture-recapture study over a six month period on experimental fields with decreased, controlled and increased predation pressure. Bird observations indicated that the ......The influence of avian predation on population size and local survival of Mastomys natalensis rats in Tanzania was studied in a capture-recapture study over a six month period on experimental fields with decreased, controlled and increased predation pressure. Bird observations indicated...... that the placement of perches increased local hunting activity of at least the Black Shouldered Kite but there were no obvious effects on rodent population size or survival. In a single field where avian predation was prevented by covering the field with a net, an increase in survival was observed. The opposite...

  2. Avian influenza

    DEFF Research Database (Denmark)

    EFSA Panel on Animal Health and Welfare; More, Simon; Bicout, Dominique

    2017-01-01

    Previous introductions of highly pathogenic avian influenza virus (HPAIV) to the EU were most likely via migratory wild birds. A mathematical model has been developed which indicated that virus amplification and spread may take place when wild bird populations of sufficient size within EU become...... infected. Low pathogenic avian influenza virus (LPAIV) may reach similar maximum prevalence levels in wild bird populations to HPAIV but the risk of LPAIV infection of a poultry holding was estimated to be lower than that of HPAIV. Only few non-wild bird pathways were identified having a non...

  3. Factors influencing the latency of simple reaction time

    Directory of Open Access Journals (Sweden)

    David L Woods

    2015-03-01

    Full Text Available Simple reaction time (SRT, the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by computer hardware and software used for SRT measurement. We developed a calibrated and temporally-precise SRT paradigm to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs. Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231 ms, 213 ms when corrected for hardware delays and increased significantly with age (0.55 ms/year, but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT was estimated by subtracting movement-initiation time, measured in a speeded finger-tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms. SRT latencies increased with age while SDT latencies did not. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in those from the Victorian era and that age-related increases in SRT latencies are due primarily to slowed motor output.

  4. Factors influencing the latency of simple reaction time.

    Science.gov (United States)

    Woods, David L; Wyma, John M; Yund, E William; Herron, Timothy J; Reed, Bruce

    2015-01-01

    Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

  5. Short (

    NARCIS (Netherlands)

    Telleman, Gerdien; den Hartog, Laurens

    2013-01-01

    Aim: This systematic review assessed the implant survival rate of short (<10 mm) dental implants installed in partially edentulous patients. A case report of a short implant in the posterior region have been added. Materials and methods: A search was conducted in the electronic databases of MEDLINE

  6. Avian cholera

    Science.gov (United States)

    Friend, Milton

    1999-01-01

    Avian cholera is a contagious disease resulting from infection by the bacterium Pasteurella multocida. Several subspecies of bacteria have been proposed for P. multocida, and at least 16 different P. multocida serotypes or characteristics of antigens in bacterial cells that differentiate bacterial variants from each other have been recognized. The serotypes are further differentiated by other methods, including DNA fingerprinting. These evaluations are useful for studying the ecology of avian cholera (Fig. 7.1), because different serotypes are generally found in poultry and free-ranging migratory birds. These evaluations also show that different P. multocida serotypes are found in wild birds in the eastern United States than those that are found in the birds in the rest of the Nation (Fig. 7.2).

  7. Short communication: isolation and phylogenetic analysis of an avian-origin H3N2 canine influenza virus in dog shelter, China.

    Science.gov (United States)

    Su, Shuo; Yuan, Ziguo; Chen, Jidang; Xie, Jiexiong; Li, Huatao; Huang, Zhen; Zhang, Minze; Du, Guohao; Chen, Zhongming; Tu, Liqing; Zou, Yufei; Miao, Junhao; Wang, Hui; Jia, Kun; Li, Shoujun

    2013-06-01

    A H3N2 canine influenza virus, A/canine/Guangdong/3/2011 (H3N2), was isolated from roaming dogs in rural China. Sequence and phylogenetic analysis of eight gene segments revealed that the A/canine/Guangdong/3/2011 (H3N2) was most similar to a recent H3N2 canine influenza virus isolated in cats from South Korea, which originated from an avian strain. To our knowledge, this is the first report of an avian-origin H3N2 CIV which was isolated from roaming dogs in China. The epidemiologic information provided herein suggests that continued study is required to determine if this virus could be established in the roaming dog population in rural China and pose potential threats to public health.

  8. The spatial scale of attention strongly modulates saccade latencies.

    Science.gov (United States)

    Harwood, Mark R; Madelain, Laurent; Krauzlis, Richard J; Wallman, Josh

    2008-04-01

    We have previously shown that when a stimulus consisting of two concentric rings moves, saccade latencies are much longer (by 150 ms) when attention is directed to the larger ring than to the smaller ring. Here, we investigated whether this effect can be explained by a deferral of the "cost" of making a saccade while the target remains inside the attentional field, or by purely visual factors (eccentricity or contrast). We found 1) latencies were shorter when attention was directed to small features irrespective of retinal eccentricity; 2) saccade latency distributions were systematically determined by the ratio between the amplitude of the stimulus step and the diameter of the attended ring: stimulus steps that were larger than the attended ring resulted in short latencies, whereas steps smaller than the attended ring resulted in proportionally longer and more variable latencies; 3) this effect was not seen in manual reaction times to the same target movement; and 4) suprathreshold changes in the contrast of targets, mimicking possible attentional effects on perceived contrast and saliency, had little effect on latency. We argue that the spatial scale of attention determines the urgency of saccade motor preparation processes by changing the rate and rate variability of the underlying decision signal, to defer the cost of saccades that result in little visual benefit.

  9. The Spatial Scale of Attention Strongly Modulates Saccade Latencies

    Science.gov (United States)

    Harwood, Mark R.; Madelain, Laurent; Krauzlis, Richard J.; Wallman, Josh

    2009-01-01

    We have previously shown that when a stimulus consisting of two concentric rings moves, saccade latencies are much longer (by 150 ms) when attention is directed to the larger ring than to the smaller ring. Here, we investigated whether this effect can be explained by a deferral of the “cost” of making a saccade while the target remains inside the attentional field, or by purely visual factors (eccentricity or contrast). We found 1) latencies were shorter when attention was directed to small features irrespective of retinal eccentricity; 2) saccade latency distributions were systematically determined by the ratio between the amplitude of the stimulus step and the diameter of the attended ring: stimulus steps that were larger than the attended ring resulted in short latencies, whereas steps smaller than the attended ring resulted in proportionally longer and more variable latencies; 3) this effect was not seen in manual reaction times to the same target movement; and 4) suprathreshold changes in the contrast of targets, mimicking possible attentional effects on perceived contrast and saliency, had little effect on latency. We argue that the spatial scale of attention determines the urgency of saccade motor preparation processes by changing the rate and rate variability of the underlying decision signal, to defer the cost of saccades that result in little visual benefit. PMID:18234988

  10. Avian influenza

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2006-06-01

    Full Text Available Avian influenza, or “bird flu”, is a contagious disease of animals which crossed the species barrier to infect humans and gave a quite impact on public health in the world since 2004, especially due to the threat of pandemic situation. Until 1st March 2006, laboratory-confirmed human cases have been reported in seven countries: Cambodia, Indonesia, Thailand, Viet Nam, China, Iraq and Turkey with a total of 174 cases and 94 dead (54.02%. Indonesia has 27 cases, 20 were dead (74.07%. AI cases in Indonesia are more in male (62.5% and all have a symptom of fever. An influenza pandemic is a rare but recurrent event. An influenza pandemic happens when a new subtype emerges that has not previously circulated in humans. For this reason, avian H5N1 is a strain with pandemic potential, since it might ultimately adapt into a strain that is contagious among humans. Impact of the pandemic could include high rates of illness and worker absenteeism are expected, and these will contribute to social and economic disruption. Historically, the number of deaths during a pandemic has varied greatly. Death rates are largely determined by four factors: the number of people who become infected, the virulence of the virus, the underlying characteristics and vulnerability of affected populations, and the effectiveness of preventive measures. Accurate predictions of mortality cannot be made before the pandemic virus emerges and begins to spread. (Med J Indones 2006; 15:125-8Keywords: Avian Influenza, Pandemic

  11. Multiple sleep latency measures in narcolepsy and behaviourally induced insufficient sleep syndrome

    OpenAIRE

    Marti, I; Valko, P O; Khatami, R; Bassetti, C L; Baumann, C R

    2009-01-01

    BACKGROUND: Short mean latencies to the first epoch of non-rapid eye movement sleep stage 1 (NREM1) and the presence of 2 sleep onset REM (SOREM) periods on multiple sleep latency test (MSLT) occur in both narcolepsy-cataplexy (NC) and behaviourally induced insufficient sleep syndrome (BIISS). It is not known whether specific MSLT findings help differentiate the two disorders. METHODS: We analyzed MSLT data including sleep latencies to and between different sleep stages of 60 age-, gender- an...

  12. Achieving low latency and energy consumption by 5G TDD mode optimization

    DEFF Research Database (Denmark)

    Lähetkangas, Eeva; Pajukoski, Kari; Vihriälä, Jaakko

    2014-01-01

    The target for a new 5G radio access technology is to support multi-Gbps and ms latency connectivity simultaneously at noticeably lower energy consumption and cost compared to the existing 4G technologies, such as LTE-Advanced. Extremely short air interface latency is required to achieve...... these requirements in a TDD-based local area network. In this paper, we discuss how the required short TDD latency can be achieved and further utilized in 5G physical air interface. First, we investigate the enablers and limits of TDD latency by analyzing the performance of OFDM in different channel environments...... and discussing on the consequent frame length limits. We then provide a description on how the achieved short TDD latency can further be utilized to enable remarkably low energy consumption. A numerical analysis comparing the battery life time of the suggested 5G TDD air interface and LTE is provided, showing...

  13. Estimation of transmission parameters of H5N1 avian influenza virus in chickens.

    Directory of Open Access Journals (Sweden)

    Annemarie Bouma

    2009-01-01

    Full Text Available Despite considerable research efforts, little is yet known about key epidemiological parameters of H5N1 highly pathogenic influenza viruses in their avian hosts. Here we show how these parameters can be estimated using a limited number of birds in experimental transmission studies. Our quantitative estimates, based on Bayesian methods of inference, reveal that (i the period of latency of H5N1 influenza virus in unvaccinated chickens is short (mean: 0.24 days; 95% credible interval: 0.099-0.48 days; (ii the infectious period of H5N1 virus in unvaccinated chickens is approximately 2 days (mean: 2.1 days; 95%CI: 1.8-2.3 days; (iii the reproduction number of H5N1 virus in unvaccinated chickens need not be high (mean: 1.6; 95%CI: 0.90-2.5, although the virus is expected to spread rapidly because it has a short generation interval in unvaccinated chickens (mean: 1.3 days; 95%CI: 1.0-1.5 days; and (iv vaccination with genetically and antigenically distant H5N2 vaccines can effectively halt transmission. Simulations based on the estimated parameters indicate that herd immunity may be obtained if at least 80% of chickens in a flock are vaccinated. We discuss the implications for the control of H5N1 avian influenza virus in areas where it is endemic.

  14. Avian respiratory system disorders

    Science.gov (United States)

    Olsen, Glenn H.

    1989-01-01

    Diagnosing and treating respiratory diseases in avian species requires a basic knowledge about the anatomy and physiology of this system in birds. Differences between mammalian and avian respiratory system function, diagnosis, and treatment are highlighted.

  15. Avian Influenza (Bird Flu)

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Subtypes Transmission of Avian Influenza A Viruses Between Animals and People Related Links Research Glossary of Influenza (Flu) Terms ...

  16. Avian Influenza in Birds

    Science.gov (United States)

    ... However, some ducks can be infected without any signs of illness. Top of Page Avian Influenza in Wild Birds Avian influenza A viruses have ... hours. Some ducks can be infected without any signs of illness. Avian influenza outbreaks are of concern in domesticated birds for ...

  17. Avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

  18. Identification of noisy response latency

    Science.gov (United States)

    Tamborrino, Massimiliano; Ditlevsen, Susanne; Lansky, Petr

    2012-08-01

    In many physical systems there is a time delay before an applied input (stimulation) has an impact on the output (response), and the quantification of this delay is of paramount interest. If the response can only be observed on top of an indistinguishable background signal, the estimation can be highly unreliable, unless the background signal is accounted for in the analysis. In fact, if the background signal is ignored, however small it is compared to the response and however large the delay is, the estimate of the time delay will go to zero for any reasonable estimator when increasing the number of observations. Here we propose a unified concept of response latency identification in event data corrupted by a background signal. It is done in the context of information transfer within a neural system, more specifically on spike trains from single neurons. The estimators are compared on simulated data and the most suitable for specific situations are recommended.

  19. Identification of noisy response latency

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano; Ditlevsen, Susanne; Lansky, Petr

    2012-01-01

    the number of observations. Here we propose a unified concept of response latency identification in event data corrupted by a background signal. It is done in the context of information transfer within a neural system, more specifically on spike trains from single neurons. The estimators are compared......In many physical systems there is a time delay before an applied input (stimulation) has an impact on the output (response), and the quantification of this delay is of paramount interest. If the response can only be observed on top of an indistinguishable background signal, the estimation can...... be highly unreliable, unless the background signal is accounted for in the analysis. In fact, if the background signal is ignored, however small it is compared to the response and however large the delay is, the estimate of the time delay will go to zero for any reasonable estimator when increasing...

  20. Onset Latency of Motor Evoked Potentials in Motor Cortical Mapping with Neuronavigated Transcranial Magnetic Stimulation.

    Science.gov (United States)

    Kallioniemi, Elisa; Pitkänen, Minna; Säisänen, Laura; Julkunen, Petro

    2015-01-01

    Cortical motor mapping in pre-surgical applications can be performed using motor evoked potential (MEP) amplitudes evoked with neuronavigated transcranial magnetic stimulation. The MEP latency, which is a more stable parameter than the MEP amplitude, has not so far been utilized in motor mapping. The latency, however, may provide information about the stress in damaged motor pathways, e.g. compression by tumors, which cannot be observed from the MEP amplitudes. Thus, inclusion of this parameter could add valuable information to the presently used technique of MEP amplitude mapping. In this study, the functional cortical representations of first dorsal interosseous (FDI), abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles were mapped in both hemispheres of ten healthy righthanded volunteers. The cortical muscle representations were evaluated by the area and centre of gravity (CoG) by using MEP amplitudes and latencies. As expected, the latency and amplitude CoGs were congruent and were located in the centre of the maps but in a few subjects, instead of a single centre, several loci with short latencies were observed. In conclusion, MEP latencies may be useful in distinguishing the cortical representation areas with the most direct pathways from those pathways with prolonged latencies. However, the potential of latency mapping to identify stressed motor tract connections at the subcortical level will need to be verified in future studies with patients.

  1. Low latency remote memory access on the Intel Paragon

    Energy Technology Data Exchange (ETDEWEB)

    Rosing, M. [Pacific Northwest Lab., Richland, WA (United States); Pierce, P. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-06-20

    We describe a cooperative project between Pacific Northwest Laboratory and Intel on providing low latency communications on the Intel Paragon. Our interest is in developing modules that are tailored to specific types of communication and are optimized for these cases. The modules described are implemented as simple extensions to the Paragon operating system. The first extension supports remote reads, writes, and accumulates on subsections of matrices. This module is intended to be used where the communication pattern is not known until run time. The second extension is designed to support low latency communication for short messages in a pipelined fashion. Finally, an interface for doing highly structured communication where the patterns of communication are well understood ahead of time is described. This is intended to be used in global communications such as global reduction.

  2. EBV Latency Types Adopt Alternative Chromatin Conformations

    Science.gov (United States)

    Tempera, Italo; Klichinsky, Michael; Lieberman, Paul M.

    2011-01-01

    Epstein-Barr Virus (EBV) can establish latent infections with distinct gene expression patterns referred to as latency types. These different latency types are epigenetically stable and correspond to different promoter utilization. Here we explore the three-dimensional conformations of the EBV genome in different latency types. We employed Chromosome Conformation Capture (3C) assay to investigate chromatin loop formation between the OriP enhancer and the promoters that determine type I (Qp) or type III (Cp) gene expression. We show that OriP is in close physical proximity to Qp in type I latency, and to Cp in type III latency. The cellular chromatin insulator and boundary factor CTCF was implicated in EBV chromatin loop formation. Combining 3C and ChIP assays we found that CTCF is physically associated with OriP-Qp loop formation in type I and OriP-Cp loop formation in type III latency. Mutations in the CTCF binding site located at Qp disrupt loop formation between Qp and OriP, and lead to the activation of Cp transcription. Mutation of the CTCF binding site at Cp, as well as siRNA depletion of CTCF eliminates both OriP-associated loops, indicating that CTCF plays an integral role in loop formation. These data indicate that epigenetically stable EBV latency types adopt distinct chromatin architectures that depend on CTCF and mediate alternative promoter targeting by the OriP enhancer. PMID:21829357

  3. EBV latency types adopt alternative chromatin conformations.

    Directory of Open Access Journals (Sweden)

    Italo Tempera

    2011-07-01

    Full Text Available Epstein-Barr Virus (EBV can establish latent infections with distinct gene expression patterns referred to as latency types. These different latency types are epigenetically stable and correspond to different promoter utilization. Here we explore the three-dimensional conformations of the EBV genome in different latency types. We employed Chromosome Conformation Capture (3C assay to investigate chromatin loop formation between the OriP enhancer and the promoters that determine type I (Qp or type III (Cp gene expression. We show that OriP is in close physical proximity to Qp in type I latency, and to Cp in type III latency. The cellular chromatin insulator and boundary factor CTCF was implicated in EBV chromatin loop formation. Combining 3C and ChIP assays we found that CTCF is physically associated with OriP-Qp loop formation in type I and OriP-Cp loop formation in type III latency. Mutations in the CTCF binding site located at Qp disrupt loop formation between Qp and OriP, and lead to the activation of Cp transcription. Mutation of the CTCF binding site at Cp, as well as siRNA depletion of CTCF eliminates both OriP-associated loops, indicating that CTCF plays an integral role in loop formation. These data indicate that epigenetically stable EBV latency types adopt distinct chromatin architectures that depend on CTCF and mediate alternative promoter targeting by the OriP enhancer.

  4. HUMAN CYTOMEGALOVIRUS LATENCY: Approaching the Gordian Knot

    Science.gov (United States)

    Goodrum, Felicia

    2017-01-01

    Herpesviruses have evolved exquisite virus-host interactions that co-opt or evade a number of host pathways to persist. Persistence of human cytomegalovirus (CMV or HCMV), the prototypical β-herpesvirus, is particularly complex in the host organism. Depending on host physiology and the cell types infected, CMV persistence is comprised of latent, chronic, and productive states that may occur concurrently. Viral latency is a central strategy by which herpesviruses ensure their life-long persistence. While much remains to be defined about the virus-host interactions important to CMV latency, it is clear that checkpoints comprised of viral and cellular factors exist to either maintain a latent state or initiate productive replication in response to host cues. CMV offers a rich platform for defining the virus-host interactions and understanding the host biology important to viral latency. This review describes current understanding of the virus-host interactions that contribute to viral latency and reactivation. PMID:27501258

  5. Long-latency reflexes account for limb biomechanics through several supraspinal pathways

    Directory of Open Access Journals (Sweden)

    Isaac Louis Kurtzer

    2015-01-01

    Full Text Available Accurate control of body posture is enforced by a multitude of corrective actions operating over a range of time scales. The earliest correction is the short-latency reflex which occurs between 20-45 ms following a sudden displacement of the limb and is generated entirely by spinal circuits. In contrast, voluntary reactions are generated by a highly distributed network but at a significantly longer delay after stimulus onset (greater than 100 ms. Between these two epochs is the long-latency reflex (around 50-100 ms which but acts more rapidly than of voluntary reactions but shares some supraspinal pathways and functional capabilities. In particular, the long-latency reflex accounts for the arm’s biomechanical properties rather than only responding to local muscle stretch like the short-latency reflex. This paper will review how the long-latency reflex accounts for the arm’s biomechanical properties and the supraspinal pathways supporting this ability. Relevant experimental paradigms include clinical studies, non-invasive brain stimulation, neural recordings in monkeys, and human behavioral studies. The sum of this effort indicates that primary motor cortex and reticular formation contribute to the the long-latency reflex either by generating or scaling its structured response appropriate for the arm’s biomechanics whereas the cerebellum scales the magnitude of the feedback response. Additional putative pathways are discussed as well as potential research lines.

  6. Latency in Distributed Acquisition and Rendering for Telepresence Systems.

    Science.gov (United States)

    Ohl, Stephan; Willert, Malte; Staadt, Oliver

    2015-12-01

    Telepresence systems use 3D techniques to create a more natural human-centered communication over long distances. This work concentrates on the analysis of latency in telepresence systems where acquisition and rendering are distributed. Keeping latency low is important to immerse users in the virtual environment. To better understand latency problems and to identify the source of such latency, we focus on the decomposition of system latency into sub-latencies. We contribute a model of latency and show how it can be used to estimate latencies in a complex telepresence dataflow network. To compare the estimates with real latencies in our prototype, we modify two common latency measurement methods. This presented methodology enables the developer to optimize the design, find implementation issues and gain deeper knowledge about specific sources of latency.

  7. Incidence and latency of radiation reactions

    International Nuclear Information System (INIS)

    Bentzen, S.M.; Thames, H.D.

    1989-01-01

    Like any other pathological condition, radiation reactions are characterized not only by their incidence (i.e. frequency) but also buy their latent period. The difference between latencies is the basis for the biologically and clinically important distinction between early and late radiation reactions. The authors conclude in this letter that a hazard-rate type of analysis does not allow separation of the effects of incidency and latency. The authors feel that a more adequate framework for analysis of latent-time distributions is provided bu the mixture model. Currenctly, the hydronephrosis data by Knowles and Trott are being reanalyzed using the model. (author). 8 refs.; 1 fig

  8. Short- and long-term protective efficacy against clade 2.3.4.4 H5N2 highly pathogenic avian influenza virus following prime-boost vaccination in turkeys

    Science.gov (United States)

    Highly pathogenic avian influenza virus (HPAIV) infections are frequently associated with systemic disease and high mortality in domestic poultry, particularly in chickens and turkeys. Clade 2.3.4.4 represents a genetic cluster within the Asian HPAIV H5 Goose/Guangdong lineage that has spread throu...

  9. Towards Controlling Latency in Wireless Networks

    KAUST Repository

    Bouacida, Nader

    2017-04-24

    Wireless networks are undergoing an unprecedented revolution in the last decade. With the explosion of delay-sensitive applications in the Internet (i.e., online gaming and VoIP), latency becomes a major issue for the development of wireless technology. Taking advantage of the significant decline in memory prices, industrialists equip the network devices with larger buffering capacities to improve the network throughput by limiting packets drops. Over-buffering results in increasing the time that packets spend in the queues and, thus, introducing more latency in networks. This phenomenon is known as “bufferbloat”. While throughput is the dominant performance metric, latency also has a huge impact on user experience not only for real-time applications but also for common applications like web browsing, which is sensitive to latencies in order of hundreds of milliseconds. Concerns have arisen about designing sophisticated queue management schemes to mitigate the effects of such phenomenon. My thesis research aims to solve bufferbloat problem in both traditional half-duplex and cutting-edge full-duplex wireless systems by reducing delay while maximizing wireless links utilization and fairness. Our work shed lights on buffer management algorithms behavior in wireless networks and their ability to reduce latency resulting from excessive queuing delays inside oversized static network buffers without a significant loss in other network metrics. First of all, we address the problem of buffer management in wireless full-duplex networks by using Wireless Queue Management (WQM), which is an active queue management technique for wireless networks. Our solution is based on Relay Full-Duplex MAC (RFD-MAC), an asynchronous media access control protocol designed for relay full-duplexing. Compared to the default case, our solution reduces the end-to-end delay by two orders of magnitude while achieving similar throughput in most of the cases. In the second part of this thesis

  10. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... outbreaks in poultry have seriously impacted livelihoods, the economy and international trade in affected countries. Other avian influenza A( ... outbreaks in poultry have seriously impacted livelihoods, the economy and international trade in affected countries. Other avian influenza A( ...

  11. The effects of parental divorce: experiences of the child in later latency.

    Science.gov (United States)

    Wallerstein, J S; Kelly, J B

    1976-04-01

    This paper discusses the impact of divorce on 31 children in later latency, as observed shortly after the initial parental separation and one year later. The material is part of an on-going clinical study, begun in 1970, of 131 children and adolescents from 60 divorcing families in Northern California.

  12. An econometric analysis of SARS and Avian flu on international tourist arrivals to Asia

    NARCIS (Netherlands)

    M.J. McAleer (Michael); B-W. Huang (Bing-Wen); H-I. Kuo (Hsiao-I); C-C. Chen (Chi-Chung); C-L. Chang (Chia-Lin)

    2008-01-01

    textabstractThis paper compares the impacts of SARS and human deaths arising from Avian Flu on international tourist arrivals to Asia. The effects of SARS and human deaths from Avian Flu will be compared directly according to human deaths. The nature of the short run and long run relationship is

  13. Group II muscle afferents probably contribute to the medium latency soleus stretch reflex during walking in humans

    DEFF Research Database (Denmark)

    Grey, Michael James; Ladouceur, Michel; Andersen, Jacob B.

    2001-01-01

    1. The objective of this study was to determine which afferents contribute to the medium latency response of the soleus stretch reflex resulting from an unexpected perturbation during human walking. 2. Fourteen healthy subjects walked on a treadmill at approximately 3.5 km h(-1) with the left ankle...... attached to a portable stretching device. The soleus stretch reflex was elicited by applying small amplitude (approximately 8 deg) dorsiflexion perturbations 200 ms after heel contact. 3. Short and medium latency responses were observed with latencies of 55 +/- 5 and 78 +/- 6 ms, respectively. The short...... the hypothesis that, during walking the medium latency component of the stretch reflex resulting from an unexpected perturbation is contributed to by group II muscle afferents....

  14. Arbitration in crossbar interconnect for low latency

    Science.gov (United States)

    Ohmacht, Martin; Sugavanam, Krishnan

    2013-02-05

    A system and method and computer program product for reducing the latency of signals communicated through a crossbar switch, the method including using at slave arbitration logic devices associated with Slave devices for which access is requested from one or more Master devices, two or more priority vector signals cycled among their use every clock cycle for selecting one of the requesting Master devices and updates the respective priority vector signal used every clock cycle. Similarly, each Master for which access is requested from one or more Slave devices, can have two or more priority vectors and can cycle among their use every clock cycle to further reduce latency and increase throughput performance via the crossbar.

  15. Targeting HIV latency: pharmacologic strategies toward eradication

    Science.gov (United States)

    Xing, Sifei; Siliciano, Robert F.

    2013-01-01

    The latent reservoir for HIV-1 in resting CD4+ T cells remains a major barrier to HIV-1 eradication, even though highly active antiretroviral therapy (HAART) can successfully reduce plasma HIV-1 levels to below the detection limit of clinical assays and reverse disease progression. Proposed eradication strategies involve reactivation of this latent reservoir. Multiple mechanisms are believed to be involved in maintaining HIV-1 latency, mostly through suppression of transcription. These include cytoplasmic sequestration of host transcription factors and epigenetic modifications such as histone deacetylation, histone methylation and DNA methylation. Therefore, strategies targeting these mechanisms have been explored for reactivation of the latent reservoir. In this review, we discuss current pharmacological approaches toward eradication, focusing on small molecule latency-reversing agents, their mechanisms, advantages and limitations. PMID:23270785

  16. Latency Minimizing Tasking for Information Processing Systems

    Energy Technology Data Exchange (ETDEWEB)

    Horey, James L [ORNL; Lagesse, Brent J [ORNL

    2011-01-01

    Real-time cyber-physical systems and information processing clusters require system designers to consider the total latency involved in collecting and aggregating data. For example, applications such as wild-fire monitoring require data to be presented to users in a timely manner. However, most models and algorithms for sensor networks have focused on alternative metrics such as energy efficiency. In this paper, we present a new model of sensor network aggregation that focuses on total latency. Our model is flexible and enables users to configure varying transmission and computation time on a node-by-node basis, and thus enables the simulation of complex computational phenomena. In addition, we present results from three tasking algorithms that trade-off local communication for overall latency performance. These algorithms are evaluated in simulated networks of up to 200 nodes. We've presented an aggregation-focused model of sensor networks that can be used to study the trade-offs between computational coverage and total latency. Our model explicitly takes into account transmission and computation times, and enables users to define different values for the basestation. In addition, we've presented three different tasking algorithms that operate over model to produce aggregation schedules of varying quality. In the future, we expect to continue exploring distributed tasking algorithms for information processing systems. We've shown that the gap between highly optimized schedules that use global information is quite large relative to our distributed algorithms. This gives us encouragement that future distributed tasking algorithms can still make large gains.

  17. Detecting Intermediary Hosts by TCP Latency Measurements

    Science.gov (United States)

    Singh, Gurvinder; Eian, Martin; Willassen, Svein Y.; Mjølsnes, Stig Fr.

    Use of intermediary hosts as stepping stones to conceal tracks is common in Internet misuse. It is therefore desirable to find a method to detect whether the originating party is using an intermediary host. Such a detection technique would allow the activation of a number of countermeasures that would neutralize the effects of misuse, and make it easier to trace a perpetrator. This work explores a new approach in determining if a host communicating via TCP is the data originator or if it is acting as a mere TCP proxy. The approach is based on measuring the inter packet arrival time at the receiving end of the connection only, and correlating the observed results with the network latency between the receiver and the proxy. The results presented here indicate that determining the use of a proxy host is possible, if the network latency between the originator and proxy is larger than the network latency between the proxy and the receiver. We show that this technique has potential to be used to detect connections were data is sent through a TCP proxy, such as remote login through TCP proxies, or rejecting spam sent through a bot network.

  18. HIV-1 Latency in Monocytes/Macrophages

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2014-04-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

  19. Glomerular latency coding in artificial olfaction

    Directory of Open Access Journals (Sweden)

    Jaber eAl Yamani

    2012-01-01

    Full Text Available Sensory perception results from the way sensory information is subsequently transformed in the brain. Olfaction is a typical example in which odor representations undergo considerable changes as they pass from olfactory receptor neurons (ORNs to second-order neurons. First, many ORNs expressing the same receptor protein yet presenting heterogeneous dose-response properties converge onto individually identifiable glomeruli. Second, onset latency of glomerular activation is believed to play a role in encoding odor quality and quantity in the context of fast information processing. Taking inspiration from the olfactory pathway, we designed a simple yet robust glomerular latency coding scheme for processing gas sensor data. The proposed bio-inspired approach was evaluated using an in-house Sn02 sensor array. Glomerular convergence was achieved by noting the possible analogy between receptor protein expressed in ORNs and metal catalyst used across the fabricated gas sensor array. Ion implantation was another technique used to account both for sensor heterogeneity and enhanced sensitivity. The response of the gas sensor array was mapped into glomerular latency patterns, whose rank order is concentration-invariant. Gas recognition was achieved by simply looking for a match within a library of spatio-temporal spike fingerprints. Because of its simplicity, this approach enables the integration of sensing and processing onto a single-chip.

  20. Data latency and the user community

    Science.gov (United States)

    Escobar, V. M.; Brown, M. E.; Carroll, M.

    2013-12-01

    The community using NASA Earth science observations in applications has grown significantly, with increasing sophistication to serve national interests. The National Research Council's Earth Science Decadal Survey report stated that the planning for applied and operational considerations in the missions should accompany the acquisition of new knowledge about Earth (NRC, 2007). This directive has made product applications at NASA an integral part of converting the data collected into actionable knowledge that can be used to inform policy. However, successfully bridging scientific research with operational decision making in different application areas requires looking into user data requirements and operational needs. This study was conducted to determine how users are incorporating NASA data into applications and operational processes. The approach included a review of published materials, direct interviews with mission representatives, and an online professional review, which was distributed to over 6000 individuals. We provide a complete description of the findings with definitions and explanations of what goes into measuring latency as well as how users and applications utilize NASA data products. We identified 3 classes of users: operational (need data in 3 hours or less), near real time (need data within a day of acquisition), and scientific users (need highest quality data, time independent). We also determined that most users with applications are interested in specific types of products that may come from multiple missions. These users will take the observations when they are available, however the observations may have additional applications value if they are available either by a certain time of day or within a period of time after acquisition. NASA has supported the need for access to low latency data on an ad-hoc basis and more substantively in stand-alone systems such as the MODIS Rapid Response system and more recently with LANCE. The increased level

  1. Temperature, latency and incubation time of Clarias gariepinus ...

    African Journals Online (AJOL)

    Latency and incubation periods of Clarias gariepinus, Heterobranchus longifilis and the incubation period of C. gariepinuseggs fertilized with sperm of H. longifiliswere studied. There was a negative correlation between the water temperature, latency and incubation periods for the two species and their hybrids. The latency ...

  2. Mobile Low Latency Services in 5G

    DEFF Research Database (Denmark)

    Cattoni, Andrea Fabio; Chandramouli, Devaki; Sartori, Cinzia

    2015-01-01

    Networks beyond 2020 will experience 10000-fold increase in wireless traffic, connect 10-100 times more devices and support the most diverse use cases. Thus, the 5G architecture needs to be flexible and cater for both traffic volumes and diversity of service requirements. Among the set of new use...... cases, support of delay sensitive "mobile" applications, such as vehicular communications (V2X, where X stands for either Vehicle or Infrastructure), require architecture enhancements to natively offer low latency and high mobility. In this paper we propose the necessary technology enablers...

  3. HIV-1 transcription and latency: an update.

    Science.gov (United States)

    Van Lint, Carine; Bouchat, Sophie; Marcello, Alessandro

    2013-06-26

    Combination antiretroviral therapy, despite being potent and life-prolonging, is not curative and does not eradicate HIV-1 infection since interruption of treatment inevitably results in a rapid rebound of viremia. Reactivation of latently infected cells harboring transcriptionally silent but replication-competent proviruses is a potential source of persistent residual viremia in cART-treated patients. Although multiple reservoirs may exist, the persistence of resting CD4+ T cells carrying a latent infection represents a major barrier to eradication. In this review, we will discuss the latest reports on the molecular mechanisms that may regulate HIV-1 latency at the transcriptional level, including transcriptional interference, the role of cellular factors, chromatin organization and epigenetic modifications, the viral Tat trans-activator and its cellular cofactors. Since latency mechanisms may also operate at the post-transcriptional level, we will consider inhibition of nuclear RNA export and inhibition of translation by microRNAs as potential barriers to HIV-1 gene expression. Finally, we will review the therapeutic approaches and clinical studies aimed at achieving either a sterilizing cure or a functional cure of HIV-1 infection, with a special emphasis on the most recent pharmacological strategies to reactivate the latent viruses and decrease the pool of viral reservoirs.

  4. HIV-1 transcription and latency: an update

    Science.gov (United States)

    2013-01-01

    Combination antiretroviral therapy, despite being potent and life-prolonging, is not curative and does not eradicate HIV-1 infection since interruption of treatment inevitably results in a rapid rebound of viremia. Reactivation of latently infected cells harboring transcriptionally silent but replication-competent proviruses is a potential source of persistent residual viremia in cART-treated patients. Although multiple reservoirs may exist, the persistence of resting CD4+ T cells carrying a latent infection represents a major barrier to eradication. In this review, we will discuss the latest reports on the molecular mechanisms that may regulate HIV-1 latency at the transcriptional level, including transcriptional interference, the role of cellular factors, chromatin organization and epigenetic modifications, the viral Tat trans-activator and its cellular cofactors. Since latency mechanisms may also operate at the post-transcriptional level, we will consider inhibition of nuclear RNA export and inhibition of translation by microRNAs as potential barriers to HIV-1 gene expression. Finally, we will review the therapeutic approaches and clinical studies aimed at achieving either a sterilizing cure or a functional cure of HIV-1 infection, with a special emphasis on the most recent pharmacological strategies to reactivate the latent viruses and decrease the pool of viral reservoirs. PMID:23803414

  5. Grid attacks avian flu

    CERN Multimedia

    2006-01-01

    During April, a collaboration of Asian and European laboratories analysed 300,000 possible drug components against the avian flu virus H5N1 using the EGEE Grid infrastructure. Schematic presentation of the avian flu virus.The distribution of the EGEE sites in the world on which the avian flu scan was performed. The goal was to find potential compounds that can inhibit the activities of an enzyme on the surface of the influenza virus, the so-called neuraminidase, subtype N1. Using the Grid to identify the most promising leads for biological tests could speed up the development process for drugs against the influenza virus. Co-ordinated by CERN and funded by the European Commission, the EGEE project (Enabling Grids for E-sciencE) aims to set up a worldwide grid infrastructure for science. The challenge of the in silico drug discovery application is to identify those molecules which can dock on the active sites of the virus in order to inhibit its action. To study the impact of small scale mutations on drug r...

  6. Low latency and persistent data storage

    Science.gov (United States)

    Fitch, Blake G; Franceschini, Michele M; Jagmohan, Ashish; Takken, Todd E

    2014-02-18

    Persistent data storage is provided by a method that includes receiving a low latency store command that includes write data. The write data is written to a first memory device that is implemented by a nonvolatile solid-state memory technology characterized by a first access speed. It is acknowledged that the write data has been successfully written to the first memory device. The write data is written to a second memory device that is implemented by a volatile memory technology. At least a portion of the data in the first memory device is written to a third memory device when a predetermined amount of data has been accumulated in the first memory device. The third memory device is implemented by a nonvolatile solid-state memory technology characterized by a second access speed that is slower than the first access speed.

  7. Avian influenza surveillance and diagnosis

    Science.gov (United States)

    Rapid detection and accurate identification of low (LPAI) and high pathogenicity avian influenza (HPAI) is critical to controlling infections and disease in poultry. Test selection and algorithms for the detection and diagnosis of avian influenza virus (AIV) in poultry may vary somewhat among differ...

  8. Comparative analysis of chest radiological findings between avian human influenza and SARS

    International Nuclear Information System (INIS)

    Cai Mingjin; Mai Weiwen; Xian Jianxing; Zhang Jiayun; Lin Wenjian; Wei Liping; Chen Jincheng

    2008-01-01

    Objective: To study the chest radiological findings of a mortal avian human influenza case. Methods: One patient in our hospital was proved to be infected avian human influenza in Guangdong province on March 1, 2006. The Clinical appearances and chest radiological findings of this case were retrospectively analyzed and compared with that of 3 mortal SARS cases out of 16 cases in 2003. Results: Large consolidated areas in left lower lobe was showed in pulmonary radiological findings of this patient and soon developed into ARDS (adult respiratory distress syndrome). However, the pulmonary radiological findings had no characteristic. Characteristics of soaring size and number during short term appeared in SARS instead of avian human influenza. Final diagnosis was up to the etiology and serology examination. Conclusion: Bronchial dissemination was not observed in this avian human influenza case. Pay attention to the avian human influenza in spite of no history of contract with sick or dead poultry in large city. (authors)

  9. Distal contraction latency: a measure of propagation velocity optimized for esophageal pressure topography studies.

    Science.gov (United States)

    Roman, Sabine; Lin, Zhiyue; Pandolfino, John E; Kahrilas, Peter J

    2011-03-01

    A defining feature of peristalsis is propagation velocity, which determines the timing of the distal contraction relative to the swallow. This study aimed to exploit a coordinate-based strategy to quantify the normal latency of the distal esophageal contraction as a measure of propagation velocity optimized for high-resolution esophageal pressure topography (EPT) studies. EPT studies for 75 healthy volunteers were merged in a computer simulation. Swallows were synchronized and analyzed as a 100 × 200 pixel grid that normalized esophageal length from the pharynx to the stomach for a 20-s period to first calculate a composite for each individual and then to establish normative values for the morphology and latency of the distal contraction among individuals. Stereotyped landmarks in composite EPT studies were pressure troughs in the proximal and distal esophagus isolating the distal segment and the contractile deceleration point (CDP) localizing the termination of peristalsis in the distal segment. Distal contractile latency was timed to the CDP (median 6.0 s, 95% confidence interval 4.8-7.6 s) and to lower esophageal sphincter (LES) contraction (median 9.2 s, 95% confidence interval 6.5-11.5 s). Illustrative examples are shown of rapidly conducted contractions with normal or short latency, suggesting short latency to be the preferable EPT metric of rapid propagation. The proposed scheme, utilizing the topographic coordinates of contraction relative to the swallow as an alternative to conventional measures of peristaltic velocity, lays the foundation for a physiologically grounded classification of peristaltic abnormalities in EPT. Future studies will test the clinical utility of this scheme.

  10. Flow Latency Analysis with the Architecture Analysis & Design Language (AADL)

    National Research Council Canada - National Science Library

    Feiler, Peter; Hansson, Jorgen

    2007-01-01

    .... The latency analysis framework and calculations are illustrated in the context of an example model that uses the flow specification notation of the Architecture Analysis & Design Language (AADL...

  11. Geographically Locating an Internet Node Using Network Latency Measurement

    National Research Council Canada - National Science Library

    Turnbaugh, Eugene

    2004-01-01

    .... The difficulties include accurate latency measure, network address translation (NAT) masking, service blocking, disparate physical configuration, dissimilar network hardware, and inaccurate and limited measuring tools...

  12. Genome Modification Technologies and Their Applications in Avian Species

    Directory of Open Access Journals (Sweden)

    Hong Jo Lee

    2017-10-01

    Full Text Available The rapid development of genome modification technology has provided many great benefits in diverse areas of research and industry. Genome modification technologies have also been actively used in a variety of research areas and fields of industry in avian species. Transgenic technologies such as lentiviral systems and piggyBac transposition have been used to produce transgenic birds for diverse purposes. In recent years, newly developed programmable genome editing tools such as transcription activator-like effector nuclease (TALEN and clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated protein 9 (CRISPR/Cas9 have also been successfully adopted in avian systems with primordial germ cell (PGC-mediated genome modification. These genome modification technologies are expected to be applied to practical uses beyond system development itself. The technologies could be used to enhance economic traits in poultry such as acquiring a disease resistance or producing functional proteins in eggs. Furthermore, novel avian models of human diseases or embryonic development could also be established for research purposes. In this review, we discuss diverse genome modification technologies used in avian species, and future applications of avian biotechnology.

  13. Avian and human metapneumovirus.

    Science.gov (United States)

    Broor, Shobha; Bharaj, Preeti

    2007-04-01

    Pneumovirus infection remains a significant problem for both human and veterinary medicine. Both avian pneumovirus (aMPV, Turkey rhinotracheitis virus) and human metapneumovirus (hMPV) are pathogens of birds and humans, which are associated with respiratory tract infections. Based on their different genomic organization and low level of nucleotide (nt) and amino acid (aa) identity with paramyxoviruses in the genus Pneumovirus, aMPV and hMPV have been classified into a new genus referred to as Metapneumovirus. The advancement of our understanding of pneumovirus biology and pathogenesis of pneumovirus disease in specific natural hosts can provide us with strategies for vaccine formulations and combined antiviral and immunomodulatory therapies.

  14. Minimal Requirements for Primary HIV Latency Models Based on a Systematic Review.

    Science.gov (United States)

    Bonczkowski, Pawel; De Scheerder, Marie-Angélique; De Spiegelaere, Ward; Vandekerckhove, Linos

    2016-01-01

    Due to the scarcity of HIV-1 latently infected cells in patients, in vitro primary latency models are now commonly used to study the HIV-1 reservoir. To this end, a number of experimental systems have been developed. Most of these models differ based on the nature of the primary CD4+ T-cell type, the used HIV strains, activation methods, and latency assessment strategies. Despite these differences, most models share some common characteristics. Here, we provide a systematic review covering the primary HIV latency models that have been used to date with the aim to compare these models and identify minimal requirements for such experiments. A systematic search on PubMed and Web of Science databases generated a short list of 17 unique publications that propose new in vitro latency models. Based on the described methods, we propose and discuss a generalized workflow, visualizing all the necessary steps to perform such an in vitro study, with the key choices and validation steps that need to be made; from cell type selection until the model readout.

  15. Effects of dynamic synapses on noise-delayed response latency of a single neuron

    Science.gov (United States)

    Uzuntarla, M.; Ozer, M.; Ileri, U.; Calim, A.; Torres, J. J.

    2015-12-01

    The noise-delayed decay (NDD) phenomenon emerges when the first-spike latency of a periodically forced stochastic neuron exhibits a maximum for a particular range of noise intensity. Here, we investigate the latency response dynamics of a single Hodgkin-Huxley neuron that is subject to both a suprathreshold periodic stimulus and a background activity arriving through dynamic synapses. We study the first-spike latency response as a function of the presynaptic firing rate f . This constitutes a more realistic scenario than previous works, since f provides a suitable biophysically realistic parameter to control the level of activity in actual neural systems. We first report on the emergence of classical NDD behavior as a function of f for the limit of static synapses. Second, we show that when short-term depression and facilitation mechanisms are included at the synapses, different NDD features can be found due to their modulatory effect on synaptic current fluctuations. For example, an intriguing double NDD (DNDD) behavior occurs for different sets of relevant synaptic parameters. Moreover, depending on the balance between synaptic depression and synaptic facilitation, single NDD or DNDD can prevail, in such a way that synaptic facilitation favors the emergence of DNDD whereas synaptic depression favors the existence of single NDD. Here we report the existence of the DNDD effect in the response latency dynamics of a neuron.

  16. Temporal, but not Directional, Prior Knowledge Shortens Muscle Reflex Latency in Response to Sudden Transition of Support Surface During Walking

    Science.gov (United States)

    Shinya, Masahiro; Kawashima, Noritaka; Nakazawa, Kimitaka

    2016-01-01

    The central nervous system takes advantage of prior knowledge about potential upcoming perturbations for modulating postural reflexes. There are two distinct aspects of prior knowledge: spatial and temporal. This study investigated how each of spatial and temporal prior knowledge contributes to the shortening of muscle response latency. Eleven participants walked on a split-belt treadmill and perturbed by sudden acceleration or deceleration of the right belt at right foot contact. Spatial prior knowledge was given by instruction of possible direction (e.g., only acceleration) of upcoming perturbation at the beginning of an experimental session. Temporal prior knowledge was given to subjects by warning tones at foot contact during three consecutive strides before the perturbation. In response to acceleration perturbation, reflexive muscle activity was observed in soleus (SOL) and gastrocnemius (GAS) muscles. Onset latency of the GAS response was shorter (72 ms vs. 58 ms) when subjects knew the timing of the upcoming perturbation, whereas the latency was independent of directional prior knowledge. SOL onset latency (44 ms) was not influenced by directional nor temporal prior knowledge. Although spinal neural circuit that mediates short-latency reflex was not influenced by the prior knowledge, excitability in supra-spinal neural circuit that mediates medium- and long-latency reflex might be enhanced by knowing the timing of the upcoming perturbation. PMID:26903838

  17. Influence of gap and overlap paradigms on saccade latencies and vergence eye movements in seven-year-old children.

    Science.gov (United States)

    Bucci, Maria Pia; Pouvreau, Nathalie; Yang, Qing; Kapoula, Zoï

    2005-07-01

    The latency of eye movements is influenced by the fixation task; when the fixation stimulus is switched off before the target presentation (gap paradigm) the latency becomes short and express movements occur. In contrast, when the fixation stimulus remains on when the target appears (overlap paradigm), eye movement latency is longer. Several previous studies have shown increased rates of express saccades in children; however the presence of an express type of latency for vergence and combined movements in children has never been explored. The present study examines the effects of the gap and the overlap paradigms on horizontal saccades at far (150 cm) and at close (20 cm) viewing distances, on vergence along the median plane, and on saccades combined with convergence or divergence in 15 normal seven-year-old children. The results show that the gap paradigm produced shorter latency for all eye movements than the overlap paradigm, but the difference was only significant for saccades at close viewing distances, for divergence (pure and combined), and for saccades combined with vergence. The gap paradigm produced significantly higher rates of express latencies for saccades at close viewing distances, for divergence, and for saccades combined with divergence; in contrast, the frequencies of express latencies for saccades at far viewing distances and for convergence (pure or combined) were similar in the gap and the overlap paradigms. Interestingly, the rate of anticipatory latencies (gap paradigm. Our collective findings suggest that the initiation of saccades at close viewing distances and of divergence is more reflexive, particularly in the gap paradigm. The finding of frequent anticipatory divergence that occurs at similar rates for seven-year-old children (this study) and for adults (Coubard et al., 2004, Exp Brain Res 154:368-381) indicates that predictive initiation of divergence is dominant.

  18. Avian Primordial Germ Cells.

    Science.gov (United States)

    Tagami, Takahiro; Miyahara, Daichi; Nakamura, Yoshiaki

    2017-01-01

    Germ cells transmit genetic information to the next generation through gametogenesis. Primordial germ cells (PGCs) are the first germ-cell population established during development, and are the common origins of both oocytes and spermatogonia. Unlike in other species, PGCs in birds undergo blood circulation to migrate toward the genital ridge, and are one of the major biological properties of avian PGCs. Germ cells enter meiosis and arrest at prophase I during embryogenesis in females, whereas in males they enter mitotic arrest during embryogenesis and enter meiosis only after birth. In chicken, gonadal sex differentiation occurs as early as embryonic day 6, but meiotic initiation of female germ cells starts from a relatively late stage (embryonic day 15.5). Retinoic acid controls meiotic entry in developing chicken gonads through the expressions of retinaldehyde dehydrogenase 2, a major retinoic acid synthesizing enzyme, and cytochrome P450 family 26, subfamily B member 1, a major retinoic acid-degrading enzyme. The other major biological property of avian PGCs is that they can be propagated in vitro for the long term, and this technique is useful for investigating proliferation mechanisms. The main factor involved in chicken PGC proliferation is fibroblast growth factor 2, which activates the signaling of MEK/ERK and thus promotes the cell cycle and anti-apoptosis. Furthermore, the activation of PI3K/Akt signaling is indispensable for the proliferation and survival of chicken PGCs.

  19. Characterizing SPDY over High Latency Satellite Channels

    Directory of Open Access Journals (Sweden)

    Luca Caviglione

    2014-12-01

    Full Text Available The increasing complexity ofWeb contents and the growing diffusion of mobile terminals, which use wireless and satellite links to get access to the Internet, impose the adoption of more specialized protocols. In particular, we focus on SPDY, a novel protocol introduced by Google to optimize the retrieval of complex webpages, to manage large Round Trip Times and high packet losses channels. In this perspective, the paper characterizes SPDY over high latency satellite links, especially with the goal of understanding whether it could be an efficient solution to cope with performance degradations typically affecting Web 2.0 services. To this aim, we implemented an experimental set-up, composed of an ad-hoc proxy, a wireless link emulator, and an instrumented Web browser. The results clearly indicate that SPDY can enhance the performances in terms of loading times, and reduce the traffic fragmentation. Moreover, owing to its connection multiplexing architecture, SPDY can also mitigate the transport layer complexity, which is critical when in presence of Performance Enhancing Proxies usually deployed to isolate satellite trunks.

  20. Human hair genealogies and stem cell latency

    Directory of Open Access Journals (Sweden)

    Tavaré Simon

    2006-02-01

    Full Text Available Abstract Background Stem cells divide to reproduce themselves and produce differentiated progeny. A fundamental problem in human biology has been the inability to measure how often stem cells divide. Although it is impossible to observe every division directly, one method for counting divisions is to count replication errors; the greater the number of divisions, the greater the numbers of errors. Stem cells with more divisions should produce progeny with more replication errors. Methods To test this approach, epigenetic errors (methylation in CpG-rich molecular clocks were measured from human hairs. Hairs exhibit growth and replacement cycles and "new" hairs physically reappear even on "old" heads. Errors may accumulate in long-lived stem cells, or in their differentiated progeny that are eventually shed. Results Average hair errors increased until two years of age, and then were constant despite decades of replacement, consistent with new hairs arising from infrequently dividing bulge stem cells. Errors were significantly more frequent in longer hairs, consistent with long-lived but eventually shed mitotic follicle cells. Conclusion Constant average hair methylation regardless of age contrasts with the age-related methylation observed in human intestine, suggesting that error accumulation and therefore stem cell latency differs among tissues. Epigenetic molecular clocks imply similar mitotic ages for hairs on young and old human heads, consistent with a restart with each new hair, and with genealogies surreptitiously written within somatic cell genomes.

  1. Low latency memory access and synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Hoenicke, Dirk (Ossining, NY); Ohmacht, Martin (Brewster, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Takken, Todd E. (Mount Kisco, NY), Vranas; Pavlos M. (Bedford Hills, NY)

    2010-10-19

    A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Bach processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.

  2. Fundamental Tradeoffs among Reliability, Latency and Throughput in Cellular Networks

    DEFF Research Database (Denmark)

    Soret, Beatriz; Mogensen, Preben; Pedersen, Klaus I.

    2014-01-01

    We address the fundamental tradeoffs among latency, reliability and throughput in a cellular network. The most important elements influencing the KPIs in a 4G network are identified, and the inter-relationships among them is discussed. We use the effective bandwidth and the effective capacity......, in which latency and reliability will be two of the principal KPIs....

  3. Analysis of Latency Performance of Bluetooth Low Energy (BLE Networks

    Directory of Open Access Journals (Sweden)

    Keuchul Cho

    2014-12-01

    Full Text Available Bluetooth Low Energy (BLE is a short-range wireless communication technology aiming at low-cost and low-power communication. The performance evaluation of classical Bluetooth device discovery have been intensively studied using analytical modeling and simulative methods, but these techniques are not applicable to BLE, since BLE has a fundamental change in the design of the discovery mechanism, including the usage of three advertising channels. Recently, there several works have analyzed the topic of BLE device discovery, but these studies are still far from thorough. It is thus necessary to develop a new, accurate model for the BLE discovery process. In particular, the wide range settings of the parameters introduce lots of potential for BLE devices to customize their discovery performance. This motivates our study of modeling the BLE discovery process and performing intensive simulation. This paper is focused on building an analytical model to investigate the discovery probability, as well as the expected discovery latency, which are then validated via extensive experiments. Our analysis considers both continuous and discontinuous scanning modes. We analyze the sensitivity of these performance metrics to parameter settings to quantitatively examine to what extent parameters influence the performance metric of the discovery processes.

  4. Analysis of latency performance of bluetooth low energy (BLE) networks.

    Science.gov (United States)

    Cho, Keuchul; Park, Woojin; Hong, Moonki; Park, Gisu; Cho, Wooseong; Seo, Jihoon; Han, Kijun

    2014-12-23

    Bluetooth Low Energy (BLE) is a short-range wireless communication technology aiming at low-cost and low-power communication. The performance evaluation of classical Bluetooth device discovery have been intensively studied using analytical modeling and simulative methods, but these techniques are not applicable to BLE, since BLE has a fundamental change in the design of the discovery mechanism, including the usage of three advertising channels. Recently, there several works have analyzed the topic of BLE device discovery, but these studies are still far from thorough. It is thus necessary to develop a new, accurate model for the BLE discovery process. In particular, the wide range settings of the parameters introduce lots of potential for BLE devices to customize their discovery performance. This motivates our study of modeling the BLE discovery process and performing intensive simulation. This paper is focused on building an analytical model to investigate the discovery probability, as well as the expected discovery latency, which are then validated via extensive experiments. Our analysis considers both continuous and discontinuous scanning modes. We analyze the sensitivity of these performance metrics to parameter settings to quantitatively examine to what extent parameters influence the performance metric of the discovery processes.

  5. Latency and User Performance in Virtual Environments and Augmented Reality

    Science.gov (United States)

    Ellis, Stephen R.

    2009-01-01

    System rendering latency has been recognized by senior researchers, such as Professor Fredrick Brooks of UNC (Turing Award 1999), as a major factor limiting the realism and utility of head-referenced displays systems. Latency has been shown to reduce the user's sense of immersion within a virtual environment, disturb user interaction with virtual objects, and to contribute to motion sickness during some simulation tasks. Latency, however, is not just an issue for external display systems since finite nerve conduction rates and variation in transduction times in the human body's sensors also pose problems for latency management within the nervous system. Some of the phenomena arising from the brain's handling of sensory asynchrony due to latency will be discussed as a prelude to consideration of the effects of latency in interactive displays. The causes and consequences of the erroneous movement that appears in displays due to latency will be illustrated with examples of the user performance impact provided by several experiments. These experiments will review the generality of user sensitivity to latency when users judge either object or environment stability. Hardware and signal processing countermeasures will also be discussed. In particular the tuning of a simple extrapolative predictive filter not using a dynamic movement model will be presented. Results show that it is possible to adjust this filter so that the appearance of some latencies may be hidden without the introduction of perceptual artifacts such as overshoot. Several examples of the effects of user performance will be illustrated by three-dimensional tracking and tracing tasks executed in virtual environments. These experiments demonstrate classic phenomena known from work on manual control and show the need for very responsive systems if they are indented to support precise manipulation. The practical benefits of removing interfering latencies from interactive systems will be emphasized with some

  6. PEALL4: a 4-channel, 12-bit, 40-MSPS, Power Efficient and Low Latency SAR ADC

    Science.gov (United States)

    Rarbi, F.; Dzahini, D.; Gallin-Martel, L.; Bouvier, J.; Zeloufi, M.; Trocme, B.; Gabaldon Ruiz, C.

    2015-01-01

    The PEALL4 chip is a Power Efficient And Low Latency 4-channels, 12-bit and 40-MSPS successive approximation register (SAR) ADC. It was designed featuring a very short latency time in the context of ATLAS Liquid Argon Calorimeter phase I upgrade. Moreover this design could be a good option for ATLAS phase II and other High Energy Physics (HEP) projects. The full functionality of the converter is achieved by an embedded high-speed clock frequency conversion generated by the ADC itself. The design and testing results of the PEALL4 chip implemented in a commercial 130nm CMOS process are presented. The size of this 4-channel ADC with embedded voltage references and sLVS output serializer is 2.8x3.4 mm2. The chip presents a short latency time less than 25 ns defined from the very beginning of the sampling to the last conversion bit made available. A total power consumption below 27mW per channel is measured including the reference buffer and the sLVS serializer.

  7. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... consultations Fact sheets Fact files Questions & answers Features Multimedia Contacts Influenza (Avian and other zoonotic) Fact sheet ... respiratory tract infection (fever and cough), early sputum production and rapid progression to severe pneumonia, sepsis with ...

  8. A Type of Low-Latency Data Gathering Method with Multi-Sink for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chao Sha

    2016-06-01

    Full Text Available To balance energy consumption and reduce latency on data transmission in Wireless Sensor Networks (WSNs, a type of low-latency data gathering method with multi-Sink (LDGM for short is proposed in this paper. The network is divided into several virtual regions consisting of three or less data gathering units and the leader of each region is selected according to its residual energy as well as distance to all of the other nodes. Only the leaders in each region need to communicate with the mobile Sinks which have effectively reduced energy consumption and the end-to-end delay. Moreover, with the help of the sleep scheduling and the sensing radius adjustment strategies, redundancy in network coverage could also be effectively reduced. Simulation results show that LDGM is energy efficient in comparison with MST as well as MWST and its time efficiency on data collection is higher than one Sink based data gathering methods.

  9. Variable impact of tizanidine on the medium latency reflex of upper and lower limbs

    DEFF Research Database (Denmark)

    Kurtzer, Isaac; Bouyer, Laurent J.; Bouffard, J.

    2018-01-01

    Sudden limb displacement evokes a complex sequence of compensatory muscle activity. Following the short-latency reflex and preceding voluntary reactions is an epoch termed the medium-latency reflex (MLR) that could reflect spinal processing of group II muscle afferents. One way to test...... this possibility is oral ingestion of tizanidine, an alpha-2 adrenergic agonist that inhibits the interneurons transmitting group II signals onto spinal motor neurons. We examined whether group II afferents contribute to MLR activity throughout the major muscles that span the elbow and shoulder. MLRs of ankle...... muscles were also tested during walking on the same day, in the same participants as well as during sitting in a different group of subjects. In contrast to previous reports, the ingestion of tizanidine had minimal impact on MLRs of arm or leg muscles during motor actions. A significant decrease...

  10. Methodology for Calculating Latency of GPS Probe Data

    Energy Technology Data Exchange (ETDEWEB)

    Young, Stanley E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Zhongxiang [University of Maryland; Hamedi, Masoud [University of Maryland

    2017-10-01

    Crowdsourced GPS probe data, such as travel time on changeable-message signs and incident detection, have been gaining popularity in recent years as a source for real-time traffic information to driver operations and transportation systems management and operations. Efforts have been made to evaluate the quality of such data from different perspectives. Although such crowdsourced data are already in widespread use in many states, particularly the high traffic areas on the Eastern seaboard, concerns about latency - the time between traffic being perturbed as a result of an incident and reflection of the disturbance in the outsourced data feed - have escalated in importance. Latency is critical for the accuracy of real-time operations, emergency response, and traveler information systems. This paper offers a methodology for measuring probe data latency regarding a selected reference source. Although Bluetooth reidentification data are used as the reference source, the methodology can be applied to any other ground truth data source of choice. The core of the methodology is an algorithm for maximum pattern matching that works with three fitness objectives. To test the methodology, sample field reference data were collected on multiple freeway segments for a 2-week period by using portable Bluetooth sensors as ground truth. Equivalent GPS probe data were obtained from a private vendor, and their latency was evaluated. Latency at different times of the day, impact of road segmentation scheme on latency, and sensitivity of the latency to both speed-slowdown and recovery-from-slowdown episodes are also discussed.

  11. Multiple Histone Lysine Methyltransferases Are Required for the Establishment and Maintenance of HIV-1 Latency

    Directory of Open Access Journals (Sweden)

    Kien Nguyen

    2017-02-01

    Full Text Available We showed previously that the histone lysine methyltransferase (HKMT H3K27me3 (EZH2 is the catalytic subunit of Polycomb repressive complex 2 (PRC2 and is required for the maintenance of HIV-1 latency in Jurkat T cells. Here we show, by using chromatin immunoprecipitation experiments, that both PRC2 and euchromatic histone-lysine N-methyltransferase 2 (EHMT2, the G9a H3K9me2-3 methyltransferase, are highly enriched at the proviral 5′ long terminal repeat (LTR and rapidly displaced upon proviral reactivation. Clustered regularly interspaced short palindromic repeat(s (CRISPR-mediated knockout of EZH2 caused depletion of both EZH2 and EHMT2, but CRISPR-mediated knockout of EHMT2 was selective for EHMT2, consistent with the failure of EHMT2 knockouts to induce latent proviruses in this system. Either (i knockout of methyltransferase by short hairpin RNA in Jurkat T cells prior to HIV-1 infection or (ii inhibition of the enzymes with drugs significantly reduced the levels of the resulting silenced viruses, demonstrating that both enzymes are required to establish latency. To our surprise, inhibition of EZH2 (by GSK-343 or EPZ-6438 or inhibition of EHMT2 (by UNC-0638 in the Th17 primary cell model of HIV latency or resting memory T cells isolated from HIV-1-infected patients receiving highly active antiretroviral therapy, was sufficient to induce the reactivation of latent proviruses. The methyltransferase inhibitors showed synergy with interleukin-15 and suberanilohydroxamic acid. We conclude that both PRC2 and EHMT2 are required for the establishment and maintenance of HIV-1 proviral silencing in primary cells. Furthermore, EZH2 inhibitors such as GSK-343 and EPZ-6438 and the EHMT2 inhibitor UNC-0638 are strong candidates for use as latency-reversing agents in clinical studies.

  12. Multiple Histone Lysine Methyltransferases Are Required for the Establishment and Maintenance of HIV-1 Latency

    Science.gov (United States)

    Nguyen, Kien; Das, Biswajit; Dobrowolski, Curtis

    2017-01-01

    ABSTRACT We showed previously that the histone lysine methyltransferase (HKMT) H3K27me3 (EZH2) is the catalytic subunit of Polycomb repressive complex 2 (PRC2) and is required for the maintenance of HIV-1 latency in Jurkat T cells. Here we show, by using chromatin immunoprecipitation experiments, that both PRC2 and euchromatic histone-lysine N-methyltransferase 2 (EHMT2), the G9a H3K9me2-3 methyltransferase, are highly enriched at the proviral 5′ long terminal repeat (LTR) and rapidly displaced upon proviral reactivation. Clustered regularly interspaced short palindromic repeat(s) (CRISPR)-mediated knockout of EZH2 caused depletion of both EZH2 and EHMT2, but CRISPR-mediated knockout of EHMT2 was selective for EHMT2, consistent with the failure of EHMT2 knockouts to induce latent proviruses in this system. Either (i) knockout of methyltransferase by short hairpin RNA in Jurkat T cells prior to HIV-1 infection or (ii) inhibition of the enzymes with drugs significantly reduced the levels of the resulting silenced viruses, demonstrating that both enzymes are required to establish latency. To our surprise, inhibition of EZH2 (by GSK-343 or EPZ-6438) or inhibition of EHMT2 (by UNC-0638) in the Th17 primary cell model of HIV latency or resting memory T cells isolated from HIV-1-infected patients receiving highly active antiretroviral therapy, was sufficient to induce the reactivation of latent proviruses. The methyltransferase inhibitors showed synergy with interleukin-15 and suberanilohydroxamic acid. We conclude that both PRC2 and EHMT2 are required for the establishment and maintenance of HIV-1 proviral silencing in primary cells. Furthermore, EZH2 inhibitors such as GSK-343 and EPZ-6438 and the EHMT2 inhibitor UNC-0638 are strong candidates for use as latency-reversing agents in clinical studies. PMID:28246360

  13. Waking Up the Sleepers: HIV Latency and Reactivation

    Directory of Open Access Journals (Sweden)

    Hoi Ping Mok

    2008-12-01

    Full Text Available In a patient infected with HIV-1, the presence of latently infected cells from which the virus can be reactivated and rekindle HIV infection in the patient necessitates lifelong administration of antiretroviral treatment. The biology of HIV latency and viral silencing is now becoming clearer at a molecular and cellular level. However, our understanding of HIV-1 latency in vivo is still inadequate. Attempts to therapeutically reactivate the virus in infected patients have yielded disappointing results. This article reviews the research and clinical findings and discusses current thinking on the subject of HIV latency and reactivation.

  14. Automatic latency equalization in VHDL-implemented complex pipelined systems

    Science.gov (United States)

    Zabołotny, Wojciech M.

    2016-09-01

    In the pipelined data processing systems it is very important to ensure that parallel paths delay data by the same number of clock cycles. If that condition is not met, the processing blocks receive data not properly aligned in time and produce incorrect results. Manual equalization of latencies is a tedious and error-prone work. This paper presents an automatic method of latency equalization in systems described in VHDL. The proposed method uses simulation to measure latencies and verify introduced correction. The solution is portable between different simulation and synthesis tools. The method does not increase the complexity of the synthesized design comparing to the solution based on manual latency adjustment. The example implementation of the proposed methodology together with a simple design demonstrating its use is available as an open source project under BSD license.

  15. Lytic Promoters Express Protein during Herpes Simplex Virus Latency

    Science.gov (United States)

    Russell, Tiffany A.; Tscharke, David C.

    2016-01-01

    Herpes simplex virus (HSV) has provided the prototype for viral latency with previously well-defined acute or lytic and latent phases. More recently, the deep quiescence of HSV latency has been questioned with evidence that lytic genes can be transcribed in this state. However, to date the only evidence that these transcripts might be translated has come from immunological studies that show activated T cells persist in the nervous system during latency. Here we use a highly sensitive Cre-marking model to show that lytic and latent phases are less clearly defined in two significant ways. First, around half of the HSV spread leading to latently infected sites occurred beyond the initial acute infection and second, we show direct evidence that lytic promoters can drive protein expression during latency. PMID:27348812

  16. Avian mycoplasmosis update

    Directory of Open Access Journals (Sweden)

    ER Nascimento

    2005-03-01

    Full Text Available Avian mycoplasmas occur in a variety of bird species. The most important mycoplasmas for chickens and turkeys are Mycoplasma gallisepticum (MG, M. synoviae (MS, and M. meleagridis. Besides, M. iowe (MI is an emerging pathogen in turkeys, but of little concern for chickens. Mycoplasmas are bacteria that lack cell wall and belong to the class Mollicutes. Although they have been considered extracellular agents, scientists admit nowadays that some of them are obligatory intracellular microorganisms, whereas all other mycoplasmas are considered facultative intracellular organisms. Their pathogenic mechanism for disease include adherence to host target cells, mediation of apoptosis, innocent bystander damage to host cell due to intimate membrane contact, molecular (antigen mimicry that may lead to tolerance, and mitotic effect for B and/or T lymphocytes, which could lead to suppressed T-cell function and/or production of cytotoxic T cell, besides mycoplasma by-products, such as hydrogen peroxide and superoxide radicals. Moreover, mycoplasma ability to stimulate macrophages, monocytes, T-helper cells and NK cells, results in the production of substances, such as tumor necrosing factor (TNF-alpha, interleukin (IL-1, 2, 6 and interferon (a, b, g. The major clinical signs seen in avian mycoplasmosis are coughing, sneezing, snicks, respiratory rales, ocular and nasal discharge, decreased feed intake and egg production, increased mortality, poor hatchability, and, primarily in turkeys, swelling of the infraorbital sinus(es. Nevertheless, chronic and unapparent infections are most common and more threatening. Mycoplasmas are transmitted horizontally, from bird to bird, and vertically, from dam to offspring through the eggs. Losses attributed to mycoplasmosis, mainly MG and MS infections, result from decreased egg production and egg quality, poor hatchability (high rate of embryonic mortality and culling of day-old birds, poor feed efficiency, increase in

  17. Altered sleep latency and arousal regulation in mice lacking norepinephrine.

    Science.gov (United States)

    Hunsley, Melissa S; Palmiter, Richard D

    2004-08-01

    Latency to sleep and the amount of sensory stimulation required to awaken an animal are measures of arousal threshold, which are ultimately modulated by an arousal regulation system involving many brain areas. Among these brain areas and network connections are wake-promoting nuclei of the brainstem and their corresponding neurotransmitters, including norepinephrine (NE). In this study, we used mice that are unable to produce NE to study its role in regulating sleep latency after a variety of interventions, and to study arousal from sleep after sleep deprivation (SD). Sleep latency was measured after gentle awakening or after injections of saline, caffeine or modafinil. Sleep latency was also measured before and after partial restoration of NE pharmacologically. Arousal threshold was measured by recording the number of decibels of white noise required to wake each mouse from NREM sleep after 0, 3 and 3 + 3 h SD (3 h SD followed by sleep, followed by an additional 3 h SD). Results showed that when mice were awakened without being touched, there were no differences in sleep latency between the genotypes. However, after an injection of saline, the control mice increased their sleep latency, whereas the NE-deficient mice did not. There were no group differences in sleep latency after treatment with either stimulant. The sleep latency difference between the genotypes was ameliorated by partial restoration of NE. The arousal threshold experiments revealed that significantly more noise was required to wake the NE-deficient mice after 3 and 3 + 3 h of SD. These findings show that mice lacking NE fall asleep more rapidly only after a mild stressor, such as an intraperitoneal injection. NE-deficient mice are also more difficult to wake up using audio stimulation after SD. The results presented here suggest that NE promotes wakefulness during transitions between sleep and wake under conditions involving mild stress and SD, but not under baseline circumstances. Copyright 2004

  18. Reducing latency when using Virtual Reality for teaching in sport

    OpenAIRE

    P Iskandar, Yulita Hanum; Gilbert, Lester; Wills, Gary

    2008-01-01

    Latency is a frequently cited shortcoming of Virtual Reality (VR) applications. To compensate for excessive latency, prediction mechanisms may use sophisticated mathematical algorithms, which may not be appropriate for complex virtual teaching applications. This paper suggests that heuristic prediction algorithms could be used to develop more effective and general systems for VR educational applications. A fast synchronization squash simulation illustrates where heuristic prediction can be us...

  19. The molecular basis of herpes simplex virus latency

    Science.gov (United States)

    Nicoll, Michael P; Proença, João T; Efstathiou, Stacey

    2012-01-01

    Herpes simplex virus type 1 is a neurotropic herpesvirus that establishes latency within sensory neurones. Following primary infection, the virus replicates productively within mucosal epithelial cells and enters sensory neurones via nerve termini. The virus is then transported to neuronal cell bodies where latency can be established. Periodically, the virus can reactivate to resume its normal lytic cycle gene expression programme and result in the generation of new virus progeny that are transported axonally back to the periphery. The ability to establish lifelong latency within the host and to periodically reactivate to facilitate dissemination is central to the survival strategy of this virus. Although incompletely understood, this review will focus on the mechanisms involved in the regulation of latency that centre on the functions of the virus-encoded latency-associated transcripts (LATs), epigenetic regulation of the latent virus genome and the molecular events that precipitate reactivation. This review considers current knowledge and hypotheses relating to the mechanisms involved in the establishment, maintenance and reactivation herpes simplex virus latency. PMID:22150699

  20. The mTOR Complex Controls HIV Latency.

    Science.gov (United States)

    Besnard, Emilie; Hakre, Shweta; Kampmann, Martin; Lim, Hyung W; Hosmane, Nina N; Martin, Alyssa; Bassik, Michael C; Verschueren, Erik; Battivelli, Emilie; Chan, Jonathan; Svensson, J Peter; Gramatica, Andrea; Conrad, Ryan J; Ott, Melanie; Greene, Warner C; Krogan, Nevan J; Siliciano, Robert F; Weissman, Jonathan S; Verdin, Eric

    2016-12-14

    A population of CD4 T lymphocytes harboring latent HIV genomes can persist in patients on antiretroviral therapy, posing a barrier to HIV eradication. To examine cellular complexes controlling HIV latency, we conducted a genome-wide screen with a pooled ultracomplex shRNA library and in vitro system modeling HIV latency and identified the mTOR complex as a modulator of HIV latency. Knockdown of mTOR complex subunits or pharmacological inhibition of mTOR activity suppresses reversal of latency in various HIV-1 latency models and HIV-infected patient cells. mTOR inhibitors suppress HIV transcription both through the viral transactivator Tat and via Tat-independent mechanisms. This inhibition occurs at least in part via blocking the phosphorylation of CDK9, a p-TEFb complex member that serves as a cofactor for Tat-mediated transcription. The control of HIV latency by mTOR signaling identifies a pathway that may have significant therapeutic opportunities. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Avian influenza : a review article

    Directory of Open Access Journals (Sweden)

    A. Yalda

    2006-07-01

    Full Text Available The purpose of this paper is to provides general information about avian influenza (bird flu and specific information about one type of bird flu, called avian influenza A (H5N1, that has caused infections in birds in Asia and Europe and in human in Asia. The main materials in this report are based on the World Health Organization (WHO , world organization for animal health (OIE , food and agriculture organization of the united nations (FAO information and recommendations and review of the published literature about avian influenza. Since December 2003, highly pathogenic H5N1 avian influenza viruses have swept through poultry populations across Asia and parts of Europe. The outbreaks are historically unprecedented in scale and geographical spread. Their economic impact on the agricultural sector of the affected countries has been large. Human cases, with an overall fatality rate around 50%, have also been reported and almost all human infections can be linked to contact with infected poultry. Influenza viruses are genetically unstable and their behaviour cannot be predicted so the risk of further human cases persists. The human health implications have now gained importance, both for illness and fatalities that have occurred following natural infection with avian viruses, and for the potential of generating a re-assortant virus that could give rise to the next human influenza pandemic.

  2. An overview on avian influenza

    Directory of Open Access Journals (Sweden)

    Nelson Rodrigo da Silva Martins

    2012-06-01

    Full Text Available Avian influenza (AI is considered an exotic disease in the Brazilian poultry industry, according to the National Avian Health Program (PNSA, with permanent monitoring of domestic, exotic and native avian species. Brazil presents privileged environmental conditions of reduced risk. In addition, all commercial poultry and conservation holdings are registered in state or national inventories and geographically located (GPS for health control. Poultry health standards are adopted for the conformity to the international market, mostly for the intensified poultry destined for exportation, but also for companion exotic and native conservation facilities. Guidelines for monitoring and the diagnosis of AI are published by the PNSA and follow the standards proposed by the international health code (World Organization for Animal Health, Organization International des Epizooties - OIE and insure the free of status for avian influenza virus (AIV of LPAIV-low pathogenicity AIV and HPAIV-high pathogenicity AIV. In addition, the infections by mesogenic and velogenic Newcastle disease virus, Mycoplasma gallisepticum, M. synoviae and M. meleagridis, Salmonella enteric subspecies enterica serovar Gallinarum biovars Gallinarum and Pullorum are eradicated from reproduction. Controlled infections by S.enterica subspecies enterica serovars Enteritidis and Typhimurium are monitored for breeders. The vaccination of chickens in ovo or at hatch against Marek's disease is mandatory. Broiler production is an indoor activity, confinement which insures biosecurity, with safe distances from the potential AIV reservoir avian species. Worldwide HPAIV H5N1 notifications to the OIE, in March 2011, included 51 countries.

  3. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2012-06-12

    ... Avian Influenza AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule... importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056...

  4. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2011-05-03

    ... Inspection Service 9 CFR Parts 93, 94, and 95 RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal... products from regions where any subtype of highly pathogenic avian influenza is considered to exist. The... vaccinated for certain types of avian influenza, or that have moved through regions where any subtype of...

  5. Mechanisms of avian songs and calls

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye

    2008-01-01

    . It consists of a skeletal framework, flexible membranes or soft tissue masses, labia, stretched between elements of this framework, and the syringeal muscles. Until a decade ago most of our knowledge about syringeal mechanics was based on such indirect evidence as electromyography, emitted sound, and anatomy....... The use of thin, flexible endoscopes has made direct observation of the syrinx possible in situ. The effects of direct muscle stimulation on the syringeal aperture have identified adductor and abductor muscles, confirming results from electromyographic studies. Endoscopic observations have revealed......-filming during sound production has revealed that sound pulses coincide with short duration formation of slots between the soft tissue masses forming a pneumatic valve, which suggests that the avian sound generating mechanism is a similar to that in the human larynx. Lately studies have revealed surprising...

  6. O plantão noturno em anestesia reduz a latência ao sono El plantón nocturno en anestesia reduce la latencia al sueño Short sleep latency in residents after a period on duty in anesthesia

    Directory of Open Access Journals (Sweden)

    Lígia Andrade da Silva Telles Mathias

    2004-10-01

    ñana, después 24 horas de trabajo, sin dormir, sin plantón en los 3 días anteriores (M2; a las 13 horas de la tarde, después de 30 horas de trabajo, sin dormir, sin plantón en los 3 días anteriores (M3. En todas esas situaciones fue realizado electroencefalograma (EEG continuo, en sala apropiada para registro de los señales de sueño, evaluándose la latencia del sueño (LS. RESULTADOS: Se Verificó reducción significativa de la LS entre los residentes, después de 24 ó 30 horas de plantón sin dormir. Entre los praticantes que tuvieron noche de sueño normal en la víspera del examen, 36,4% presentaron LS en nivel considerado patológico. CONCLUSIONES: La jornada de plantón de 24 ó 30 horas lleva a valores de LS menores que 5 minutos, considerados patológicos, reflejando la fatiga extrema de residentes de Anestesiologia. Pode ser importante la reglamentación del número de horas de descanso pos-plantón.BACKGROUND AND OBJECTIVES: Physicians in general, and anesthesiologists in particular, have long working hours. Residents of Anesthesiology may present significant fatigue and stress. This study aimed at investigating first and second year residents’ sleep latency after a period on duty. METHODS: Participated in this study 11 residents in different situations: at 7:00 am, after a normal night sleep (> 7 h, without on duty period in the last 3 days (M1; at 7:00 am, after 24h of night work, without on duty period in the last 3 days (M2; and at 1:00 pm after 30h of work without on duty period in the last 3 days (M3. Continuous EEG was performed for all situations in adequate room to record sleep signals. Sleep latency (SL was evaluated. RESULTS: There has been significant shorter SL among residents after 24 or 30 hours without sleep. From residents after a normal night sleep the day before the evaluation, 36.4% presented pathological SL levels. CONCLUSIONS: Periods on duty for 24 or 30 hours lead to SL values below 5 minutes, which are considered pathologic and

  7. Impact of Bimodal Traffic on Latency in Optical Burst Switching Networks

    Directory of Open Access Journals (Sweden)

    Yuhua Chen

    2008-01-01

    Full Text Available This paper analyzes the impact of bimodal traffic composition on latency in optical burst switching networks. In particular, it studies the performance degradation to short-length packets caused by longer packets, both of which are part of a heterogeneous traffic model. The paper defines a customer satisfaction index for each of the classes of traffic, and a composite satisfaction index. The impact of higher overall utilization of the network as well as that of the ratio of the traffic mix on each of the customer satisfaction indices is specifically addressed.

  8. On the Impact of Multi-User Traffic Dynamics on Low Latency Communications

    DEFF Research Database (Denmark)

    Gerardino, Guillermo Andrés Pocovi; Pedersen, Klaus I.; Alvarez, Beatriz Soret

    2016-01-01

    In this paper we study the downlink latency performance in a multi-user cellular network. We use a flexible 5G radio frame structure, where the TTI size is configurable on a per-user basis according to their specific service requirements. Results show that at low system loads using a short TTI (e...... efficiency) provide better performance as these better cope with the non-negligible queuing delay. The presented results allow to conclude that support for scheduling with different TTI sizes is important for LLC and should be included in the future 5G....

  9. Avian reproductive physiology

    Science.gov (United States)

    Gee, G.F.; Gibbons, Edward F.; Durrant, Barbara S.; Demarest, Jack

    1995-01-01

    Knowledge of the many physiological factors associated with egg production , fertility, incubation, and brooding in nondomestic birds is limited. Science knows even less about reproduction in most of the 238 endangered or threatened birds. This discussion uses studies of nondomestic and, when necessary, domestic birds to describe physiological control of reproduction. Studies of the few nondomestic avian species show large variation in physiological control of reproduction. Aviculturists, in order to successfully propagate an endangered bird, must understand the bird's reproductive peculiarities. First, investigators can do studies with carefully chosen surrogate species, but eventually they need to confirm the results in the target endangered bird. Studies of reproduction in nondomestic birds increased in the last decade. Still, scientists need to do more comparative studies to understand the mechanisms that control reproduction in birds. New technologies are making it possible to study reproductive physiology of nondomestic species in less limiting ways. These technologies include telemetry to collect information without inducing stress on captives (Howey et al., 1987; Klugman, 1987), new tests for most of the humoral factors associated with reproduction, and the skill to collect small samples and manipulate birds without disrupting the physiological mechanisms (Bercovitz et al., 1985). Managers are using knowledge from these studies to improve propagation in zoological parks, private and public propagation facilities, and research institutions. Researchers need to study the control of ovulation, egg formation, and oviposition in the species of nondomestic birds that lay very few eggs in a season, hold eggs in the oviduct for longer intervals, or differ in other ways from the more thoroughly studied domestic birds. Other techniques that would enhance propagation for nondomestlc birds include tissue culture of cloned embryonic cells, cryopreservation of embryos

  10. A Gene-Based Analysis of Acoustic Startle Latency

    Science.gov (United States)

    Smith, Alicia K.; Jovanovic, Tanja; Kilaru, Varun; Lori, Adriana; Gensler, Lauren; Lee, Samuel S.; Norrholm, Seth Davin; Massa, Nicholas; Cuthbert, Bruce; Bradley, Bekh; Ressler, Kerry J.; Duncan, Erica

    2017-01-01

    Latency of the acoustic startle response is the time required from the presentation of startling auditory stimulus until the startle response is elicited and provides an index of neural processing speed. Latency is prolonged in subjects with schizophrenia compared to controls in some but not all studies and is 68–90% heritable in baseline startle trials. In order to determine the genetic association with latency as a potential inroad into genetically based vulnerability to psychosis, we conducted a gene-based study of latency followed by an independent replication study of significant gene findings with a single-nucleotide polymorphism (SNP)-based analysis of schizophrenia and control subjects. 313 subjects from an urban population of low socioeconomic status with mixed psychiatric diagnoses were included in the gene-based study. Startle testing was conducted using a Biopac M150 system according to our published methods. Genotyping was performed with the Omni-Quad 1M or the Omni Express BeadChip. The replication study was conducted on 154 schizophrenia subjects and 123 psychiatric controls. Genetic analyses were conducted with Illumina Human Omni1-Quad and OmniExpress BeadChips. Twenty-nine SNPs were selected from four genes that were significant in the gene-based analysis and also associated with startle and/or schizophrenia in the literature. Linear regressions on latency were conducted, controlling for age, race, and diagnosis as a dichotomous variable. In the gene-based study, 2,870 genes demonstrated the evidence of association after correction for multiple comparisons (false discovery rate < 0.05). Pathway analysis of these genes revealed enrichment for relevant biological processes including neural transmission (p = 0.0029), synaptic transmission (p = 0.0032), and neuronal development (p = 0.024). The subsequent SNP-based replication analysis revealed a strong association of onset latency with the SNP rs901561 on the neuregulin gene (NRG1

  11. Latency in Visionic Systems: Test Methods and Requirements

    Science.gov (United States)

    Bailey, Randall E.; Arthur, J. J., III; Williams, Steven P.; Kramer, Lynda J.

    2005-01-01

    A visionics device creates a pictorial representation of the external scene for the pilot. The ultimate objective of these systems may be to electronically generate a form of Visual Meteorological Conditions (VMC) to eliminate weather or time-of-day as an operational constraint and provide enhancement over actual visual conditions where eye-limiting resolution may be a limiting factor. Empirical evidence has shown that the total system delays or latencies including the imaging sensors and display systems, can critically degrade their utility, usability, and acceptability. Definitions and measurement techniques are offered herein as common test and evaluation methods for latency testing in visionics device applications. Based upon available data, very different latency requirements are indicated based upon the piloting task, the role in which the visionics device is used in this task, and the characteristics of the visionics cockpit display device including its resolution, field-of-regard, and field-of-view. The least stringent latency requirements will involve Head-Up Display (HUD) applications, where the visionics imagery provides situational information as a supplement to symbology guidance and command information. Conversely, the visionics system latency requirement for a large field-of-view Head-Worn Display application, providing a Virtual-VMC capability from which the pilot will derive visual guidance, will be the most stringent, having a value as low as 20 msec.

  12. Mechanisms of Kaposi's Sarcoma-Associated Herpesvirus Latency and Reactivation

    Directory of Open Access Journals (Sweden)

    Fengchun Ye

    2011-01-01

    Full Text Available The life cycle of Kaposi's sarcoma-associated herpesvirus (KSHV consists of latent and lytic replication phases. During latent infection, only a limited number of KSHV genes are expressed. However, this phase of replication is essential for persistent infection, evasion of host immune response, and induction of KSHV-related malignancies. KSHV reactivation from latency produces a wide range of viral products and infectious virions. The resulting de novo infection and viral lytic products modulate diverse cellular pathways and stromal microenvironment, which promote the development of Kaposi's sarcoma (KS. The mechanisms controlling KSHV latency and reactivation are complex, involving both viral and host factors, and are modulated by diverse environmental factors. Here, we review the cellular and molecular basis of KSHV latency and reactivation with a focus on the most recent advancements in the field.

  13. Effects of psychot herapy on REM latency and REM time.

    Science.gov (United States)

    Karle, W; Hopper, M; Switzer, A; Corriere, R; Woldenberg, L

    1980-08-01

    This study investigated the effect of a functional psychotherapy on the sleep EEG patterns of 6 patients. Contrary to original expectations no significant group differences in REM time and REM latency were found between two nights following therapy sessions and two normal nights. However, across the 4 nights the patients exhibited an average REM latency of 71 min. which was significantly shorter than that recorded in an independent study with the same design and a similar subject population. Clausen, Sersen, and Lidsky (1974) reported an average REM latency of 107.3 min. for 10 normal subjects also recorded across four nights. This result is compared with those in several other studies and discussed in relation to possible changes in dream patterns.

  14. Influenza vaccines for avian species

    Science.gov (United States)

    Beginning in Southeast Asia, in 2003, a multi-national epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity an...

  15. Control strategies against avian influenza

    Science.gov (United States)

    Since 1959, 40 epizootics of high pathogenicity avian influenza (HPAI) have occurred (Figure 1). Thirty-five of these epizootic HPAI viruses were geographically-limited (mostly to single countries), involved farm-to-farm spread and were eradicated from poultry by stamping-out programs; i.e. the HPAI...

  16. Avian metapneumovirus in the USA

    Science.gov (United States)

    In the United States of America (USA), avian metapneumovirus (aMPV) causes an upper respiratory tract infection in turkeys; no outbreaks have been reported in commercial chicken flocks. Typical clinical signs of the disease in turkey poults include coughing, sneezing, nasal discharge, tracheal rale...

  17. Reverse genetics of avian metapneumoviruses

    Science.gov (United States)

    An overview of avian metapneumovirus (aMPV) infection in turkeys and development of a reverse genetics system for aMPV subgroup C (aMPV-C) virus will be presented. By using reverse genetics technology, we generated recombinant aMPV-C viruses containing a different length of glycoprotein (G) gene or...

  18. CpG methylation controls reactivation of HIV from latency.

    Directory of Open Access Journals (Sweden)

    Jana Blazkova

    2009-08-01

    Full Text Available DNA methylation of retroviral promoters and enhancers localized in the provirus 5' long terminal repeat (LTR is considered to be a mechanism of transcriptional suppression that allows retroviruses to evade host immune responses and antiretroviral drugs. However, the role of DNA methylation in the control of HIV-1 latency has never been unambiguously demonstrated, in contrast to the apparent importance of transcriptional interference and chromatin structure, and has never been studied in HIV-1-infected patients. Here, we show in an in vitro model of reactivable latency and in a latent reservoir of HIV-1-infected patients that CpG methylation of the HIV-1 5' LTR is an additional epigenetic restriction mechanism, which controls resistance of latent HIV-1 to reactivation signals and thus determines the stability of the HIV-1 latency. CpG methylation acts as a late event during establishment of HIV-1 latency and is not required for the initial provirus silencing. Indeed, the latent reservoir of some aviremic patients contained high proportions of the non-methylated 5' LTR. The latency controlled solely by transcriptional interference and by chromatin-dependent mechanisms in the absence of significant promoter DNA methylation tends to be leaky and easily reactivable. In the latent reservoir of HIV-1-infected individuals without detectable plasma viremia, we found HIV-1 promoters and enhancers to be hypermethylated and resistant to reactivation, as opposed to the hypomethylated 5' LTR in viremic patients. However, even dense methylation of the HIV-1 5'LTR did not confer complete resistance to reactivation of latent HIV-1 with some histone deacetylase inhibitors, protein kinase C agonists, TNF-alpha, and their combinations with 5-aza-2deoxycytidine: the densely methylated HIV-1 promoter was most efficiently reactivated in virtual absence of T cell activation by suberoylanilide hydroxamic acid. Tight but incomplete control of HIV-1 latency by Cp

  19. Scalla: Structured Cluster Architecture for Low Latency Access

    Energy Technology Data Exchange (ETDEWEB)

    Hanushevsky, Andrew; Wang, Daniel L.; /SLAC

    2012-03-20

    Scalla is a distributed low-latency file access system that incorporates novel techniques that minimize latency and maximize scalability over a large distributed system with a distributed namespace. Scalla's techniques have shown to be effective in nearly a decade of service for the high-energy physics community using commodity hardware and interconnects. We describe the two components used in Scalla that are instrumental in its ability to provide low-latency, fault-tolerant name resolution and load distribution, and enable its use as a high-throughput, low-latency communication layer in the Qserv system, the Large Synoptic Survey Telescope's (LSST's) prototype astronomical query system. Scalla arguably exceeded its three main design objectives: low latency, scaling, and recoverability. In retrospect, these objectives were met using a simple but effective design. Low latency was met by uniformly using linear or constant time algorithms in all high-use paths, avoiding locks whenever possible, and using compact data structures to maximize the memory caching efficiency. Scaling was achieved by architecting the system as a 64-ary tree. Nodes can be added easily and as the number of nodes increases, search performance increases at an exponential rate. Recoverability is inherent in that no permanent state information is maintained and whatever state information is needed it can be quickly constructed or reconstructed in real time. This allows dynamic changes in a cluster of servers with little impact on over-all performance or usability. Today, Scalla is being deployed in environments and for uses that were never conceived in 2001. This speaks well for the systems adaptability but the underlying reason is that the system can meet its three fundamental objectives at the same time.

  20. Pudendal nerve latency time in normal women via intravaginal stimulation

    Directory of Open Access Journals (Sweden)

    Geraldo A. Cavalcanti

    2006-12-01

    Full Text Available INTRODUCTION & OBJECTIVES: Studies of motor conduction for the efferent functional assessment of the pudendal nerve in women with pelvic dysfunctions have been conducted through researching distal motor latency times. The transrectal approach has been the classic approach for this electrophysiological examination. The objective of the present study is to verify the viability of the transvaginal approach in performing the exam, to establish normal values for this method and to analyze the influence of age, stature and parity in the latency value of normal women. MATERIALS AND METHODS: A total of 23 volunteers without genitourinary pathologies participated in this study. In each, pudendal motor latency was investigated through the transvaginal approach, which was chosen due to patient’s higher tolerance levels. RESULTS: The motor response represented by registering the M-wave was obtained in all volunteers on the right side (100% and in 13 volunteers on the left side (56.5%. The mean motor latency obtained in the right and left was respectively: 1.99 ± 0.41 and 1.92 ± 0.48 milliseconds (ms. There was no difference between the sides (p = 0.66. Latency did not correlate with age, stature or obstetric history. The results obtained in the present study were in agreement with those found by other researchers using the transrectal approach. CONCLUSION: The vaginal approach represents an alternative for pudendal nerve distal motor latency time, with similar results to those achieved through the transrectal approach. Normative values obtained herein might serve as a comparative basis for subsequent physiopathological studies.

  1. Immune evasion proteins enhance cytomegalovirus latency in the lungs.

    Science.gov (United States)

    Böhm, Verena; Seckert, Christof K; Simon, Christian O; Thomas, Doris; Renzaho, Angélique; Gendig, Dorothea; Holtappels, Rafaela; Reddehase, Matthias J

    2009-10-01

    CD8 T cells control cytomegalovirus (CMV) infection in bone marrow transplantation recipients and persist in latently infected lungs as effector memory cells for continuous sensing of reactivated viral gene expression. Here we have addressed the question of whether viral immunoevasins, glycoproteins that specifically interfere with antigen presentation to CD8 T cells, have an impact on viral latency in the murine model. The data show that deletion of immunoevasin genes in murine CMV accelerates the clearance of productive infection during hematopoietic reconstitution and leads to a reduced latent viral genome load, reduced latency-associated viral transcription, and a lower incidence of recurrence in lung explants.

  2. The determinants of spoken and written picture naming latencies.

    Science.gov (United States)

    Bonin, Patrick; Chalard, Marylène; Méot, Alain; Fayol, Michel

    2002-02-01

    The influence of nine variables on the latencies to write down or to speak aloud the names of pictures taken from Snodgrass and Vanderwart (1980) was investigated in French adults. The major determinants of both written and spoken picture naming latencies were image variability, image agreement and age of acquisition. To a lesser extent, name agreement was also found to have an impact in both production modes. The implications of the findings for theoretical views of both spoken and written picture naming are discussed.

  3. Latency Performance of Encoding with Random Linear Network Coding

    DEFF Research Database (Denmark)

    Nielsen, Lars; Hansen, René Rydhof; Lucani Rötter, Daniel Enrique

    2018-01-01

    In this paper, we present a performance study of the impact of generation and symbol sizes on latency for encoding with Random Linear Network Coding (RLNC). This analysis is important for low latency applications of RLNC as well as data storage applications that use large blocks of data, where...... the encoding process can be parallelized based on system requirements to reduce data access time within the system. Using a counting argument, we focus on predicting the effect of changes of generation (number of original packets) and symbol size (number of bytes per data packet) configurations on the encoding...

  4. Optimizing latency in Xilinx FPGA implementations of the GBT

    CERN Document Server

    Muschter, S; Bohm, C; Cachemiche, J-P; Baron, S

    2010-01-01

    The GigaBit Transceiver (GBT) {[}1] system has been developed to replace the Timing, Trigger and Control (TTC) system {[}2], currently used by LHC, as well as to provide data transmission between on-detector and off-detector components in future sLHC detectors. A VHDL version of the GBT-SERDES, designed for FPGAs, was released in March 2010 as a GBT-FPGA Starter Kit for future GBT users and for off-detector GBT implementation {[}3]. This code was optimized for resource utilization {[}4], as the GBT protocol is very demanding. It was not, however, optimized for latency - which will be a critical parameter when used in the trigger path. The GBT-FPGA Starter Kit firmware was first analyzed in terms of latency by looking at the separate components of the VHDL version. Once the parts which contribute most to the latency were identified and modified, two possible optimizations were chosen, resulting in a latency reduced by a factor of three. The modifications were also analyzed in terms of logic utilization. The la...

  5. Time and direction preparation of the long latency stretch reflex.

    Science.gov (United States)

    Nikaido, Yasutaka; Hatanaka, Ryota; Jono, Yasutomo; Nomura, Yoshifumi; Tani, Keisuke; Chujo, Yuta; Hiraoka, Koichi

    2016-06-01

    This study investigated time and direction preparation of motor response to force load while intending to maintain the finger at the initial neutral position. Force load extending or flexing the index finger was given while healthy humans intended to maintain the index finger at the initial neutral position. Electromyographic activity was recorded from the first dorsal interosseous muscle. A precue with or without advanced information regarding the direction of the forthcoming force load was given 1000ms before force load. Trials without the precue were inserted between the precued trials. A long latency stretch reflex was elicited by force load regardless of its direction, indicating that the long latency stretch reflex is elicited not only by muscle stretch afferents, but also by direction-insensitive sensations. Time preparation of motor response to either direction of force load enhanced the long latency stretch reflex, indicating that time preparation is not mediated by afferent discharge of muscle stretch. Direction preparation enhanced the long latency stretch reflex and increased corticospinal excitability 0-20ms after force load when force load was given in the direction stretching the muscle. These enhancements must be induced by preset of the afferent pathway mediating segmental stretch reflex. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Monitoring data transfer latency in CMS computing operations

    CERN Document Server

    Bonacorsi, D; Magini, N; Sartirana, A; Taze, M; Wildish, T

    2015-01-01

    During the first LHC run, the CMS experiment collected tens of Petabytes of collision and simulated data, which need to be distributed among dozens of computing centres with low latency in order to make efficient use of the resources. While the desired level of throughput has been successfully achieved, it is still common to observe transfer workflows that cannot reach full completion in a timely manner due to a small fraction of stuck files which require operator intervention.For this reason, in 2012 the CMS transfer management system, PhEDEx, was instrumented with a monitoring system to measure file transfer latencies, and to predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies while the transfer is still in progress, and monitor the long-term performance of the transfer infrastructure to plan the data placement strategy.Based on the data collected for one year with the latency monitoring system, we present a study on the different fact...

  7. Presynaptic Spontaneous Activity Enhances the Accuracy of Latency Coding

    Czech Academy of Sciences Publication Activity Database

    Leváková, Marie; Tamborrino, M.; Košťál, Lubomír; Lánský, Petr

    2016-01-01

    Roč. 28, č. 10 (2016), s. 2162-2180 ISSN 0899-7667 R&D Projects: GA MŠk 7AMB15AT010; GA ČR(CZ) GA15-08066S Institutional support: RVO:67985823 Keywords : neural coding * first-spike latency * spontaneous activity Subject RIV: FH - Neurology Impact factor: 1.938, year: 2016

  8. Accuracy of averaged auditory brainstem response amplitude and latency estimates

    DEFF Research Database (Denmark)

    Madsen, Sara Miay Kim; M. Harte, James; Elberling, Claus

    2017-01-01

    Objective: The aims were to 1) establish which of the four algorithms for estimating residual noise level and signal-to-noise ratio (SNR) in auditory brainstem responses (ABRs) perform better in terms of post-average wave-V peak latency and amplitude errors and 2) determine whether SNR or noise...

  9. Interventions in live poultry markets for the control of avian influenza: A systematic review

    Directory of Open Access Journals (Sweden)

    Vittoria Offeddu

    2016-12-01

    Conclusions: The evidence collected in this review endorses permanent LPM-closure as a long-term objective to reduce the zoonotic risk of avian influenza, although its economic and socio-political implications favour less drastic interventions, e.g. weekly rest days, for implementation in the short-term.

  10. Evidence-Based Advances in Avian Medicine.

    Science.gov (United States)

    Summa, Noémie M; Guzman, David Sanchez-Migallon

    2017-09-01

    This article presents relevant advances in avian medicine and surgery over the past 5 years. New information has been published to improve clinical diagnosis in avian diseases. This article also describes new pharmacokinetic studies. Advances in the understanding and treatment of common avian disorders are presented in this article, as well. Although important progress has been made over the past years, there is still much research that needs to be done regarding the etiology, pathophysiology, diagnosis, and treatment of avian diseases and evidence-based information is still sparse in the literature. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Avian Influenza infection in Human

    Directory of Open Access Journals (Sweden)

    Mohan. M

    2008-08-01

    Full Text Available Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds.All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in humans. There is no evidence, to date that efficient human to human transmission of H5N1 strain has occurred and very often. Efficient transmission among humans is a key property of pandemic strains and a property that the avian H5N1 and H9N2 viruses apparently lacked. The biological and molecular basis for effective aerosol transmission among humans is not known. The virus can improve its transmissibility among humans via two principal mechanisms. The first is a “reassortment” event, in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig.Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread. The second mechanism is a more gradual process of adaptive mutation, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early. As the number of human infections grows, the risk increases that a new virus subtype could emerge, triggering an influenza pandemic. Humans as well as swine must now be considered a potential mixing vessel for the generation of such a virus. This link between widespread infection in poultry and increased risk of human

  12. Using EGEE against avian flu

    CERN Multimedia

    2006-01-01

    During April 2006 avian flu was spreading across the world with the potential of turning into a pandemic, a drug to treat the deadly H5N1 strain was needed. Such a task required the huge processing power provided by EGEE, which analysed 300 000 possible drug components for their suitability. This map shows the network of computer centres and their activity during this time.

  13. Gender determination of avian embryo

    Energy Technology Data Exchange (ETDEWEB)

    Daum, Keith A. (Idaho Falls, ID); Atkinson, David A. (Idaho Falls, ID)

    2002-01-01

    Disclosed is a method for gender determination of avian embryos. During the embryo incubation process, the outer hard shells of eggs are drilled and samples of allantoic fluid are removed. The allantoic fluids are directly introduced into an ion mobility spectrometer (IMS) for analysis. The resulting spectra contain the relevant marker peaks in the positive or negative mode which correlate with unique mobilities which are sex-specific. This way, the gender of the embryo can be determined.

  14. Medium-latency stretch reflexes of foot and leg muscles analysed by cooling the lower limb in standing humans.

    Science.gov (United States)

    Schieppati, M; Nardone, A

    1997-09-15

    1. In standing subjects, an ankle-dorsiflexing perturbation of the supporting surface evokes a short-latency response (SLR) and a medium-latency response (MLR) to stretch in both soleus (Sol) and flexor digitorum brevis (FDB) muscles. The SLR is the counterpart of the monosynaptic reflex, whilst the MLR might be either mediated by Ia fibres, the delay being due to a long-loop central circuit, or by fibres of slower conduction velocity. Since small afferents are slowed more than large ones by low temperature, a greater latency increment for the MLR than the SLR induced by cooling of the limb would point to a peripheral origin of the MLR. 2. In nine subjects, one limb was cooled by circulating water in a tube wrapped around it for about 120 min. Perturbations were delivered to the same limb prior to and during cooling, and after rewarming. EMG was recorded by surface electrodes from the Sol and FDB muscles. 3. The mean increase in latency of MLRs was significantly greater than that of SLRs in both muscles. On average, the Sol SLR increased from 42.4 to 47.0 ms and the Sol MLR from 72.0 to 82.3 ms. The FDB SLR increased from 58.1 to 66.5 ms and the FDB MLR from 94.9 to 110.5 ms. The mean difference (MLR minus SLR) increased from 29.6 to 35.2 ms for Sol, and from 36.8 to 43.9 ms for FDB at the end of cooling. After 30 min of rewarming, the responses of both muscles recovered towards control values. 4. The greater latency increment of the MLRs than of the SLRs favours the hypothesis of a slower conduction velocity of the responsible afferent fibres. The most likely candidate fibres are the spindle group II afferents.

  15. Understanding of and possible strategies to avian influenza outbreak.

    Science.gov (United States)

    Shen, Junkang; Zhang, Andy; Xu, Huifen; Sirois, Pierre; Zhang, Jia; Li, Kai; Xiao, Li

    2013-01-01

    Swine flu and avian flu outbreaks have occurred in recent years in addition to seasonal flu. As mortality rate records are not available at the early stage of an outbreak, two parameters may be useful to assess the viral virulence : 1. the time required for the first domestic case in a newly involved region, and 2. the doubling time of new infected cases. Viral virulence is one of the most important factors in guiding short term and immediate responses. Although routine surveillance and repeated vaccination are useful efforts, some novel strategies that may be relevant to prevent and control the spread of influenza among human beings and domestic animals are discussed.

  16. Signaling filopodia in avian embryogenesis: formation and function

    Directory of Open Access Journals (Sweden)

    Margarethe Draga

    2016-11-01

    Full Text Available In vertebrates and invertebrates specialized cellular protrusions, called signaling filopodia or cytonemes, play an important role in cell-cell communication by carrying receptors and ligands to distant cells to activate various signaling pathways. In the chicken embryo, signaling filopodia were described in limb bud mesenchyme and in somite epithelia. The formation of signaling filopodia depends on the activity of Rho GTPases and reorganization of the cytoskeleton. Here, we give a short overview on the present knowledge on avian signaling filopodia and discuss the molecular basis of cytoskeletal rearrangements leading to filopodia formation.

  17. Rewards modulate saccade latency but not exogenous spatial attention.

    Science.gov (United States)

    Dunne, Stephen; Ellison, Amanda; Smith, Daniel T

    2015-01-01

    The eye movement system is sensitive to reward. However, whilst the eye movement system is extremely flexible, the extent to which changes to oculomotor behavior induced by reward paradigms persist beyond the training period or transfer to other oculomotor tasks is unclear. To address these issues we examined the effects of presenting feedback that represented small monetary rewards to spatial locations on the latency of saccadic eye movements, the time-course of learning and extinction of the effects of rewarding saccades on exogenous spatial attention and oculomotor inhibition of return. Reward feedback produced a relative facilitation of saccadic latency in a stimulus driven saccade task which persisted for three blocks of extinction trials. However, this hemifield-specific effect failed to transfer to peripheral cueing tasks. We conclude that rewarding specific spatial locations is unlikely to induce long-term, systemic changes to the human oculomotor or attention systems.

  18. Molecular Basis of Latency in Pathogenic Human Viruses

    Science.gov (United States)

    Garcia-Blanco, Mariano A.; Cullen, Bryan R.

    1991-11-01

    Several human viruses are able to latently infect specific target cell populations in vivo. Analysis of the replication cycles of herpes simplex virus, Epstein-Barr virus, and human immunodeficiency virus suggests that the latent infections established by these human pathogens primarily result from a lack of host factors critical for the expression of viral early gene products. The subsequent activation of specific cellular transcription factors in response to extracellular stimuli can induce the expression of these viral regulatory proteins and lead to a burst of lytic viral replication. Latency in these eukaryotic viruses therefore contrasts with latency in bacteriophage, which is maintained primarily by the expression of virally encoded repressors of lytic replication.

  19. Long release latencies are increased by acetylcholine at frog endplate

    Czech Academy of Sciences Publication Activity Database

    Samigullin, D.; Bukharaeva, E. A.; Nikolsky, E.; Adámek, S.; Vyskočil, František

    2003-01-01

    Roč. 52, č. 4 (2003), s. 475-480 ISSN 0862-8408 R&D Projects: GA ČR GA305/02/1333; GA ČR GA202/02/1213 Grant - others:RFBR(RU) 02/04/48901 Institutional research plan: CEZ:AV0Z5011922; CEZ:MSM 113100003 Keywords : quantal release * acetylcholine * synaptic latency Subject RIV: ED - Physiology Impact factor: 0.939, year: 2003

  20. Hipster: hybrid task manager for latency-critical cloud workloads

    OpenAIRE

    Nishtala, Rajiv; Carpenter, Paul M.; Petrucci, Vinicius; Martorell Bofill, Xavier

    2017-01-01

    In 2013, U. S. data centers accounted for 2.2% of the country's total electricity consumption, a figure that is projected to increase rapidly over the next decade. Many important workloads are interactive, and they demand strict levels of quality-of-service (QoS) to meet user expectations, making it challenging to reduce power consumption due to increasing performance demands. This paper introduces Hipster, a technique that combines heuristics and reinforcement learning to manage latency-crit...

  1. Auditory middle latency response in children with learning difficulties.

    Science.gov (United States)

    Frizzo, Ana Claudia Figueiredo; Issac, Myriam Lima; Pontes-Fernandes, Angela Cristina; Menezes, Pedro de Lemos; Funayama, Carolina Araújo Rodrigues

    2012-07-01

     This is an objective laboratory assessment of the central auditory systems of children with learning disabilities.  To examine and determine the properties of the components of the Auditory Middle Latency Response in a sample of children with learning disabilities.  This was a prospective, cross-sectional cohort study with quantitative, descriptive, and exploratory outcomes. We included 50 children aged 8-13 years of both genders with and without learning disorders. Those with disorders of known organic, environmental, or genetic causes were excluded.  The Na, Pa, and Nb waves were identified in all subjects. The ranges of the latency component values were as follows: Na = 9.8-32.3 ms, Pa = 19.0-51.4 ms, Nb = 30.0-64.3 ms (learning disorders group) and Na = 13.2-29.6 ms, Pa = 21.8-42.8 ms, Nb = 28.4-65.8 ms (healthy group). The values of the Na-Pa amplitude ranged from 0.3 to 6.8 ìV (learning disorders group) or 0.2-3.6 ìV (learning disorders group). Upon analysis, the functional characteristics of the groups were distinct: the left hemisphere Nb latency was longer in the study group than in the control group. Peculiarities of the electrophysiological measures were observed in the children with learning disorders. This study has provided information on the Auditory Middle Latency Response and can serve as a reference for other clinical and experimental studies in children with these disorders.

  2. CpG methylation controls reactivation of HIV from latency

    Czech Academy of Sciences Publication Activity Database

    Blažková, Jana; Trejbalová, Kateřina; Gondois-Rey, F.; Halfon, P.; Philibert, P.; Guiguen, A.; Verdin, E.; Olive, D.; Van Lint, C.; Hejnar, Jiří; Hirsch, I.

    2009-01-01

    Roč. 5, č. 8 (2009), e1000554-e1000554 E-ISSN 1553-7374 R&D Projects: GA ČR GA204/05/0939; GA ČR GP204/08/P616 Institutional research plan: CEZ:AV0Z50520514 Keywords : HIV-1 * proviral latency * CpG methylation * histone modifications * HAART * epigenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.978, year: 2009

  3. Cerebellar damage diminishes long-latency responses to multijoint perturbations

    Science.gov (United States)

    Trautman, Paxson; Rasquinha, Russell J.; Bhanpuri, Nasir H.; Scott, Stephen H.; Bastian, Amy J.

    2013-01-01

    Damage to the cerebellum can cause significant problems in the coordination of voluntary arm movements. One prominent idea is that incoordination stems from an inability to predictively account for the complex mechanical interactions between the arm's several joints. Motivated by growing evidence that corrective feedback control shares important capabilities and neural substrates with feedforward control, we asked whether cerebellar damage impacts feedback stabilization of the multijoint arm appropriate for the arm's intersegmental dynamics. Specifically, we tested whether cerebellar dysfunction impacts the ability of posterior deltoid to incorporate elbow motion in its long-latency response (R2 = 45–75 ms and R3 = 75–100 ms after perturbation) to an unexpected torque perturbation. Healthy and cerebellar-damaged subjects were exposed to a selected pattern of shoulder-elbow displacements to probe the response pattern from this shoulder extensor muscle. The healthy elderly subjects expressed a long-latency response linked to both shoulder and elbow motion, including an increase/decrease in shoulder extensor activity with elbow flexion/extension. Critically, cerebellar-damaged subjects displayed the normal pattern of activity in the R3 period indicating an intact ability to rapidly integrate multijoint motion appropriate to the arm's intersegmental dynamics. However, cerebellar-damaged subjects had a lower magnitude of activity that was specific to the long-latency period (both R2 and R3) and a slightly delayed onset of multijoint sensitivity. Taken together, our results suggest that the basic motor pattern of the long-latency response is housed outside the cerebellum and is scaled by processes within the cerebellum. PMID:23390311

  4. Short communications: Avian mortality rates on a power line near ...

    African Journals Online (AJOL)

    Scopus: Journal of East African Ornithology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 34 (2015) >. Log in or Register to get access to full text downloads.

  5. Statistical learning methods for aero-optic wavefront prediction and adaptive-optic latency compensation

    Science.gov (United States)

    Burns, W. Robert

    Since the early 1970's research in airborne laser systems has been the subject of continued interest. Airborne laser applications depend on being able to propagate a near diffraction-limited laser beam from an airborne platform. Turbulent air flowing over the aircraft produces density fluctuations through which the beam must propagate. Because the index of refraction of the air is directly related to the density, the turbulent flow imposes aberrations on the beam passing through it. This problem is referred to as Aero-Optics. Aero-Optics is recognized as a major technical issue that needs to be solved before airborne optical systems can become routinely fielded. This dissertation research specifically addresses an approach to mitigating the deleterious effects imposed on an airborne optical system by aero-optics. A promising technology is adaptive optics: a feedback control method that measures optical aberrations and imprints the conjugate aberrations onto an outgoing beam. The challenge is that it is a computationally-difficult problem, since aero-optic disturbances are on the order of kilohertz for practical applications. High control loop frequencies and high disturbance frequencies mean that adaptive-optic systems are sensitive to latency in sensors, mirrors, amplifiers, and computation. These latencies build up to result in a dramatic reduction in the system's effective bandwidth. This work presents two variations of an algorithm that uses model reduction and data-driven predictors to estimate the evolution of measured wavefronts over a short temporal horizon and thus compensate for feedback latency. The efficacy of the two methods are compared in this research, and evaluated against similar algorithms that have been previously developed. The best version achieved over 75% disturbance rejection in simulation in the most optically active flow region in the wake of a turret, considerably outperforming conventional approaches. The algorithm is shown to be

  6. Using Arduino microcontroller boards to measure response latencies.

    Science.gov (United States)

    Schubert, Thomas W; D'Ausilio, Alessandro; Canto, Rosario

    2013-12-01

    Latencies of buttonpresses are a staple of cognitive science paradigms. Often keyboards are employed to collect buttonpresses, but their imprecision and variability decreases test power and increases the risk of false positives. Response boxes and data acquisition cards are precise, but expensive and inflexible, alternatives. We propose using open-source Arduino microcontroller boards as an inexpensive and flexible alternative. These boards connect to standard experimental software using a USB connection and a virtual serial port, or by emulating a keyboard. In our solution, an Arduino measures response latencies after being signaled the start of a trial, and communicates the latency and response back to the PC over a USB connection. We demonstrated the reliability, robustness, and precision of this communication in six studies. Test measures confirmed that the error added to the measurement had an SD of less than 1 ms. Alternatively, emulation of a keyboard results in similarly precise measurement. The Arduino performs as well as a serial response box, and better than a keyboard. In addition, our setup allows for the flexible integration of other sensors, and even actuators, to extend the cognitive science toolbox.

  7. SMYD2-Mediated Histone Methylation Contributes to HIV-1 Latency.

    Science.gov (United States)

    Boehm, Daniela; Jeng, Mark; Camus, Gregory; Gramatica, Andrea; Schwarzer, Roland; Johnson, Jeffrey R; Hull, Philip A; Montano, Mauricio; Sakane, Naoki; Pagans, Sara; Godin, Robert; Deeks, Steven G; Krogan, Nevan J; Greene, Warner C; Ott, Melanie

    2017-05-10

    Transcriptional latency of HIV is a last barrier to viral eradication. Chromatin-remodeling complexes and post-translational histone modifications likely play key roles in HIV-1 reactivation, but the underlying mechanisms are incompletely understood. We performed an RNAi-based screen of human lysine methyltransferases and identified the SET and MYND domain-containing protein 2 (SMYD2) as an enzyme that regulates HIV-1 latency. Knockdown of SMYD2 or its pharmacological inhibition reactivated latent HIV-1 in T cell lines and in primary CD4 + T cells. SMYD2 associated with latent HIV-1 promoter chromatin, which was enriched in monomethylated lysine 20 at histone H4 (H4K20me1), a mark lost in cells lacking SMYD2. Further, we find that lethal 3 malignant brain tumor 1 (L3MBTL1), a reader protein with chromatin-compacting properties that recognizes H4K20me1, was recruited to the latent HIV-1 promoter in a SMYD2-dependent manner. We propose that a SMYD2-H4K20me1-L3MBTL1 axis contributes to HIV-1 latency and can be targeted with small-molecule SMYD2 inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Seasonality, distribution and taxonomic status of avian ...

    African Journals Online (AJOL)

    Description of a new species is based upon morphology of gametocyte development in the peripheral blood of the avian host. This does not distinguish between morphologically identical gametocytes from different avian host families, nor is species or family level a valid taxonomic character. Thus, Haemoproteus and ...

  9. Mechanisms of avian songs and calls

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye

    2008-01-01

    The avian vocal organ, the syrinx, is a specialized structure located rather inaccessibly in an air sac close to the heart where the trachea bifurcates into the two primary bronchi. The syrinx of different avian taxa varies so much in position and morphology that it has been used for taxonomy. It...

  10. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  11. Avian Influenza Policy Analysis | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Governments in Southeast Asia have adopted a range of policies aimed at controlling the disease in animals, preventing its spread to humans and strengthening national preparedness for an avian influenza pandemic. The Asia Partnership for Avian Influenza Research (APAIR) brings together national research agencies ...

  12. MANAGING AVIAN FLU, CARCASS MANAGEMENT & BIOSOLIDS

    Science.gov (United States)

    The avian influenza virus is discussed with emphasis on the impact to poultry and possible movement of the highly pathogenic H5N 1 virus to humans. A review is made of the worldwide effects to date of the avian influenza viruses; methods for the viruses to enter recreational wate...

  13. Innovation and discovery: the application of nucleic acid-based technology to avian virus detection and characterization.

    Science.gov (United States)

    Cavanagh, D

    2001-12-01

    Polymerase chain reaction (PCR)-based approaches to the detection, differentiation and characterization of avian pathogens continue to be developed and refined. The PCRs, or reverse transcriptase-PCRs, may be general, designed to detect all or most variants of a pathogen, or to be serotype, genotype or pathotype specific. Progress is being made with respect to making nucleic acid approaches more suitable for use in diagnostic laboratories. Robotic workstations are now available for extraction of nucleic acid from many samples in a short time, for routine diagnosis. Following general PCR, the DNA products are commonly analyzed by restriction endonuclease mapping (restriction fragment length polymorphism), using a small number of restriction endonucleases, based on a large body of sequence data. Increasingly, however, nucleotide sequencing is being used to analyze the DNA product, in part due to the expanding use of non-radioactive sequencing methods that are safe and enable high throughout. In this review, I highlight some recent developments with many avian viruses: Newcastle disease virus; circoviruses in canary and pigeon; infectious bursal disease virus (Gumboro disease virus); avian adenoviruses, including Angara disease/infectious hydropericardium virus, haemorrhagic enteritis virus of turkeys, and egg drop syndrome virus; avian herpesviruses, including infectious laryngotracheitis virus, duck plague virus, psittacine herpesvirus (Pacheco's parrot disease virus), Marek's disease virus and herpesvirus of turkeys; avian leukosis virus (associated with lymphoid leukosis or myeloid leukosis, and egg transmission); avian pneumoviruses (turkey rhinotracheitis virus); avian coronaviruses, including infectious bronchitis virus, turkey coronavirus and pheasant coronavirus; astrovirus, in the context of poult enteritis and mortality syndrome, and avian nephritis virus; and avian encephalomyelitis virus, a picornavirus related to hepatitis A virus.

  14. Detecting concealed information in less than a second: response latency-based measures

    NARCIS (Netherlands)

    Verschuere, B.; de Houwer, J.; Verschuere, B.; Ben-Shakhar, G.; Meijer, E.

    2011-01-01

    Concealed information can be accurately assessed with physiological measures. To overcome the practical limitations of physiological measures, an assessment using response latencies has been proposed. At first sight, research findings on response latency based concealed information tests seem

  15. Short-latency local actions of nerve growth factor at the growth cone.

    OpenAIRE

    Seeley, P J; Greene, L A

    1983-01-01

    Cultures of neurite-bearing pheochromocytoma (PC12) cells and of sympathetic neurons have been examined by time-lapse video microscopy. In the presence of nerve growth factor (NGF), the neurites of such cultures elongated and their growth cones changed geometry, via microspike and lamellipodial motion, on a time scale of minutes. Withdrawal of NGF caused process extension to cease and a progressive reduction in growth-cone area as a result of retraction of lamellipodia and microspikes. By app...

  16. Relationships between avian richness and landscape structure at multiple scales using multiple landscapes

    Science.gov (United States)

    Mitchell, M.S.; Rutzmoser, S.H.; Wigley, T.B.; Loehle, C.; Gerwin, J.A.; Keyser, P.D.; Lancia, R.A.; Perry, R.W.; Reynolds, C.J.; Thill, R.E.; Weih, R.; White, D.; Wood, P.B.

    2006-01-01

    Little is known about factors that structure biodiversity on landscape scales, yet current land management protocols, such as forest certification programs, place an increasing emphasis on managing for sustainable biodiversity at landscape scales. We used a replicated landscape study to evaluate relationships between forest structure and avian diversity at both stand and landscape-levels. We used data on bird communities collected under comparable sampling protocols on four managed forests located across the Southeastern US to develop logistic regression models describing relationships between habitat factors and the distribution of overall richness and richness of selected guilds. Landscape models generated for eight of nine guilds showed a strong relationship between richness and both availability and configuration of landscape features. Diversity of topographic features and heterogeneity of forest structure were primary determinants of avian species richness. Forest heterogeneity, in both age and forest type, were strongly and positively associated with overall avian richness and richness for most guilds. Road density was associated positively but weakly with avian richness. Landscape variables dominated all models generated, but no consistent patterns in metrics or scale were evident. Model fit was strong for neotropical migrants and relatively weak for short-distance migrants and resident species. Our models provide a tool that will allow managers to evaluate and demonstrate quantitatively how management practices affect avian diversity on landscapes.

  17. Avian cholera, a threat to the viability of an Arctic seabird colony?

    Directory of Open Access Journals (Sweden)

    Sébastien Descamps

    Full Text Available Evidence that infectious diseases cause wildlife population extirpation or extinction remains anecdotal and it is unclear whether the impacts of a pathogen at the individual level can scale up to population level so drastically. Here, we quantify the response of a Common eider colony to emerging epidemics of avian cholera, one of the most important infectious diseases affecting wild waterfowl. We show that avian cholera has the potential to drive colony extinction, even over a very short period. Extinction depends on disease severity (the impact of the disease on adult female survival and disease frequency (the number of annual epidemics per decade. In case of epidemics of high severity (i.e., causing >30% mortality of breeding females, more than one outbreak per decade will be unsustainable for the colony and will likely lead to extinction within the next century; more than four outbreaks per decade will drive extinction to within 20 years. Such severity and frequency of avian cholera are already observed, and avian cholera might thus represent a significant threat to viability of breeding populations. However, this will depend on the mechanisms underlying avian cholera transmission, maintenance, and spread, which are currently only poorly known.

  18. Structural and Biomechanical Properties of the Exchange Tissue of the Avian Lung.

    Science.gov (United States)

    Maina, John N

    2015-10-01

    The blood capillaries (BC) and the air capillaries (ACs) are the terminal gas exchange units of the avian lung. The minuscule structures are astonishingly strong. It is only recently that the morphologies and the biomechanical properties of the BCs and the ACs were investigated. Regarding size and shape, the BCs and the ACs differ remarkably. While they were previously claimed to be tubular (cylindrical) in shape, the ACs are rather rotund structures which interconnect across short, narrow passageways. Atypical of those in other tissues, the BCs in the exchange tissue of the avian lung comprise of distinct segments which are about as long as they are wide and which are coupled in three-dimensions. The thin blood-gas barrier (BGB) which separates the ACs from the BCs is peculiarly strong. The causes of the strengths of the ACs and the BCs in general and the BGB in particular are varied and controversial. Here, the recent morphological and physiological findings on the structure, biomechanical properties, and the strengths of the respiratory units of the avian lung and the BGB have been critically examined. Also, in light of the new morphological findings of the ACs and the BCs, the functional model which is currently in use to assess the gas exchange efficiency of the avian lung should be revised and the inappropriateness of the terms 'blood capillary' and 'air capillary' for the gas exchange units of the avian lung is pointed out. © 2015 Wiley Periodicals, Inc.

  19. A Somatosensory Latency between the Thalamus and Cortex also Correlates with Level of Intelligence.

    Science.gov (United States)

    Reed, T. Edward; Jensen, Arthur R.

    1993-01-01

    Results for sensory thalamocortical latency (3 somatosensory evoked potentials) for 205 college students agree with data that correlate a more extensive visual evoked potential latency with intelligence quotient. Findings suggest that the correlation occurs because the latency indexes cortical nerve conduction velocity. (SLD)

  20. THE AVIAN FLU IMPACT ON THE ROMANIAN POULTRY MARKET

    Directory of Open Access Journals (Sweden)

    Silvius Stanciu

    2015-05-01

    Full Text Available Poultry meat represents one of the most dynamic branches of the local meat production. The poultry sector represents a good quality protein source, at an acceptable price as compared to other animal production domains. There has been an ascending evolution of the sector after the year 2000, although there appeared a series of discontinuities that affected agricultural production, mainly on a short-term basis. The Avian Flu led to 190 million euros’ worth losses at the level of Romanian national economy. Low consumption due to the impact was a short-term consequence, being rapidly amortized by the Romanian producers. The lack of some business continuity insurance measures can further affect the poultry meat sector, which does not have the necessary robustness needed in case of larger shocks. The following article proposes an analysis of the Avian Flu crisis economic effects on the Romanian meat sector, and it is part of a general framework of research regarding the Romanian food chain resilience to critical situations.

  1. Genetic applications in avian conservation

    Science.gov (United States)

    Haig, Susan M.; Bronaugh, Whitcomb M.; Crowhurst, Rachel S.; D'Elia, Jesse; Eagles-Smith, Collin A.; Epps, Clinton W.; Knaus, Brian; Miller, Mark P.; Moses, Michael L.; Oyler-McCance, Sara; Robinson, W. Douglas; Sidlauskas, Brian

    2011-01-01

    A fundamental need in conserving species and their habitats is defining distinct entities that range from individuals to species to ecosystems and beyond (Table 1; Ryder 1986, Moritz 1994, Mayden and Wood 1995, Haig and Avise 1996, Hazevoet 1996, Palumbi and Cipriano 1998, Hebert et al. 2004, Mace 2004, Wheeler et al. 2004, Armstrong and Ball 2005, Baker 2008, Ellis et al. 2010, Winker and Haig 2010). Rapid progression in this interdisciplinary field continues at an exponential rate; thus, periodic updates on theory, techniques, and applications are important for informing practitioners and consumers of genetic information. Here, we outline conservation topics for which genetic information can be helpful, provide examples of where genetic techniques have been used best in avian conservation, and point to current technical bottlenecks that prevent better use of genomics to resolve conservation issues related to birds. We hope this review will provide geneticists and avian ecologists with a mutually beneficial dialogue on how this integrated field can solve current and future problems.

  2. Avian Respiratory Coinfection and Impact on Avian Influenza Pathogenicity in Domestic Poultry: Field and Experimental Findings.

    Science.gov (United States)

    Samy, Ahmed; Naguib, Mahmoud M

    2018-02-24

    The avian respiratory system hosts a wide range of commensal and potential pathogenic bacteria and/or viruses that interact with each other. Such interactions could be either synergistic or antagonistic, which subsequently determines the severity of the disease complex. The intensive rearing methods of poultry are responsible for the marked increase in avian respiratory diseases worldwide. The interaction between avian influenza with other pathogens can guarantee the continuous existence of other avian pathogens, which represents a global concern. A better understanding of the impact of the interaction between avian influenza virus and other avian respiratory pathogens provides a better insight into the respiratory disease complex in poultry and can lead to improved intervention strategies aimed at controlling virus spread.

  3. CTCF prevents the epigenetic drift of EBV latency promoter Qp.

    Directory of Open Access Journals (Sweden)

    Italo Tempera

    2010-08-01

    Full Text Available The establishment and maintenance of Epstein-Barr Virus (EBV latent infection requires distinct viral gene expression programs. These gene expression programs, termed latency types, are determined largely by promoter selection, and controlled through the interplay between cell-type specific transcription factors, chromatin structure, and epigenetic modifications. We used a genome-wide chromatin-immunoprecipitation (ChIP assay to identify epigenetic modifications that correlate with different latency types. We found that the chromatin insulator protein CTCF binds at several key regulatory nodes in the EBV genome and may compartmentalize epigenetic modifications across the viral genome. Highly enriched CTCF binding sites were identified at the promoter regions upstream of Cp, Wp, EBERs, and Qp. Since Qp is essential for long-term maintenance of viral genomes in type I latency and epithelial cell infections, we focused on the role of CTCF in regulating Qp. Purified CTCF bound approximately 40 bp upstream of the EBNA1 binding sites located at +10 bp relative to the transcriptional initiation site at Qp. Mutagenesis of the CTCF binding site in EBV bacmids resulted in a decrease in the recovery of stable hygromycin-resistant episomes in 293 cells. EBV lacking the Qp CTCF site showed a decrease in Qp transcription initiation and a corresponding increase in Cp and Fp promoter utilization at 8 weeks post-transfection. However, by 16 weeks post-transfection, bacmids lacking CTCF sites had no detectable Qp transcription and showed high levels of histone H3 K9 methylation and CpG DNA methylation at the Qp initiation site. These findings provide direct genetic evidence that CTCF functions as a chromatin insulator that prevents the promiscuous transcription of surrounding genes and blocks the epigenetic silencing of an essential promoter, Qp, during EBV latent infection.

  4. CTCF Prevents the Epigenetic Drift of EBV Latency Promoter Qp

    Science.gov (United States)

    Tempera, Italo; Wiedmer, Andreas; Dheekollu, Jayaraju; Lieberman, Paul M.

    2010-01-01

    The establishment and maintenance of Epstein-Barr Virus (EBV) latent infection requires distinct viral gene expression programs. These gene expression programs, termed latency types, are determined largely by promoter selection, and controlled through the interplay between cell-type specific transcription factors, chromatin structure, and epigenetic modifications. We used a genome-wide chromatin-immunoprecipitation (ChIP) assay to identify epigenetic modifications that correlate with different latency types. We found that the chromatin insulator protein CTCF binds at several key regulatory nodes in the EBV genome and may compartmentalize epigenetic modifications across the viral genome. Highly enriched CTCF binding sites were identified at the promoter regions upstream of Cp, Wp, EBERs, and Qp. Since Qp is essential for long-term maintenance of viral genomes in type I latency and epithelial cell infections, we focused on the role of CTCF in regulating Qp. Purified CTCF bound ∼40 bp upstream of the EBNA1 binding sites located at +10 bp relative to the transcriptional initiation site at Qp. Mutagenesis of the CTCF binding site in EBV bacmids resulted in a decrease in the recovery of stable hygromycin-resistant episomes in 293 cells. EBV lacking the Qp CTCF site showed a decrease in Qp transcription initiation and a corresponding increase in Cp and Fp promoter utilization at 8 weeks post-transfection. However, by 16 weeks post-transfection, bacmids lacking CTCF sites had no detectable Qp transcription and showed high levels of histone H3 K9 methylation and CpG DNA methylation at the Qp initiation site. These findings provide direct genetic evidence that CTCF functions as a chromatin insulator that prevents the promiscuous transcription of surrounding genes and blocks the epigenetic silencing of an essential promoter, Qp, during EBV latent infection. PMID:20730088

  5. Delayed Latency of Postural Muscles of Individuals with Intellectual Disabilities

    Directory of Open Access Journals (Sweden)

    J. Walter Tolentino-Castro

    2018-02-01

    Full Text Available Individuals with intellectual disabilities (ID (50 < IQ < 79 show impaired motor and postural control, these impairments are highly related to falls and injuries. Recent studies demonstrated these impairments are related with fine and gross motor development, which are more strongly associated with cognition, and consequently language for individuals with ID than for without ID. Despite these studies, little is known about the structure and functioning of this population's spinal cord, which is highly involved in postural control. The aim of our study was to assess the latency of the reflex responses in postural muscles after unexpected lateral external perturbations, in individuals with intellectual disabilities compared to typically developed participants. We assessed 16 participants with intellectual disabilities, 9 males and 7 females (aged 24.06 ± 8.66 years and 20 typical developed participants (CG, 11 females, 9 males, (aged 21.20±1.96 years. While the participants were in an upright standing position electromyography was used to collect data from M. obliquus externus abdominis (OE muscles, which were activated by unpredictable perturbations applied by a servomotor on a hand-held grip, following the lateral external perturbation to the trunk. The intellectual disabilities group presented contralateral OE muscles latency of 85.71±27.24 ms, and CG group presented 68.62±10.25 ms, no differences was found. Ipsilateral OE muscles latency also did not differs between the groups, ID group showed 96.60±30.20 ms and CG group showed 95.57±33.53 ms. Our study furthers the knowledge about the muscular activity of individuals with intellectual disabilities. The present experimental results may suggest unique spinal cord processing of individuals with intellectual disabilities when they are faced with unexpected lateral external perturbations.

  6. First-spike latency in the presence of spontaneous activity

    Czech Academy of Sciences Publication Activity Database

    Pawlas, Z.; Klebanov, L. B.; Beneš, V.; Prokešová, M.; Popelář, Jiří; Lánský, Petr

    2010-01-01

    Roč. 22, č. 7 (2010), s. 1675-1693 ISSN 0899-7667 R&D Projects: GA ČR(CZ) GA309/07/1336; GA MŠk(CZ) LC554 Grant - others:GA AVCR(CZ) IAA101120604; GA ČR(CZ) GP201/08/P100 Program:IA Institutional research plan: CEZ:AV0Z50390703; CEZ:AV0Z50110509 Keywords : spike trans * inferior colliculus * response latency Subject RIV: FH - Neurology Impact factor: 2.290, year: 2010

  7. The Development of Defense Mechanisms During the Latency Period.

    Science.gov (United States)

    Cramer, Phebe

    2018-02-06

    The developmental period of latency, during middle childhood, has not been previously studied for possible change in the use of defense mechanisms. Using a validated narrative method to assess defenses, the present research examines change in children's defense use during this period. As predicted from theory, there was a significant increase in the use of the defense of Identification. This finding is consistent with theory that posits a shift at this time from defense against anxiety that is based on lack of impulse control to defense that is based on anxiety due to violation of conscience.

  8. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    OpenAIRE

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2012-01-01

    Please cite this paper as: Hall et al. (2012) Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00358.x. Background  Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are l...

  9. The effect of apparent latency on simulator sickness while using a see-through helmet-mounted display: reducing apparent latency with predictive compensation.

    Science.gov (United States)

    Buker, Timothy J; Vincenzi, Dennis A; Deaton, John E

    2012-04-01

    The aim of this study was to determine the effect of head movement frequency and predictive compensation on (a) latency produced in a monocular see-through helmet-mounted display (HMD) test bed and (b) simulator sickness experienced by users wearing the HMD. There is conflicting research regarding latency as a significant factor in the onset of simulator sickness. Predictive compensation has been shown to mitigate the magnitude of latency, but little is known about the extent of its effect on simulator sickness. A video camera recorded HMD and simulator imagery to accurately measure apparent latency produced at three head movement frequencies. Predictive compensation strategies were manipulated to measure the difference in apparent latency produced by the test bed in various conditions. Similar methodology was employed with human participants to measure simulator sickness experienced by users of this test bed. In Experiment 1, apparent latency increased significantly as head movement frequency increased. Predictive compensation strategies significantly reduced apparent latency present in the test bed. In Experiment 2, predictive compensation significantly reduced the magnitude of simulator sickness. Predictive compensation can be effectively implemented to reduce apparent latency, resulting in a lower magnitude of simulator sickness. Potential applications include HMD use in which head position is tracked and visual imagery is linked to head or body movement, such as in virtual and augmented reality systems, and is thus critical to functionality and performance.

  10. Monitoring auditory cortical plasticity in hearing aid users with long latency auditory evoked potentials: a longitudinal study.

    Science.gov (United States)

    Leite, Renata Aparecida; Magliaro, Fernanda Cristina Leite; Raimundo, Jeziela Cristina; Bento, Ricardo Ferreira; Matas, Carla Gentile

    2018-02-19

    The objective of this study was to compare long-latency auditory evoked potentials before and after hearing aid fittings in children with sensorineural hearing loss compared with age-matched children with normal hearing. Thirty-two subjects of both genders aged 7 to 12 years participated in this study and were divided into two groups as follows: 14 children with normal hearing were assigned to the control group (mean age 9 years and 8 months), and 18 children with mild to moderate symmetrical bilateral sensorineural hearing loss were assigned to the study group (mean age 9 years and 2 months). The children underwent tympanometry, pure tone and speech audiometry and long-latency auditory evoked potential testing with speech and tone burst stimuli. The groups were assessed at three time points. The study group had a lower percentage of positive responses, lower P1-N1 and P2-N2 amplitudes (speech and tone burst), and increased latencies for the P1 and P300 components following the tone burst stimuli. They also showed improvements in long-latency auditory evoked potentials (with regard to both the amplitude and presence of responses) after hearing aid use. Alterations in the central auditory pathways can be identified using P1-N1 and P2-N2 amplitude components, and the presence of these components increases after a short period of auditory stimulation (hearing aid use). These findings emphasize the importance of using these amplitude components to monitor the neuroplasticity of the central auditory nervous system in hearing aid users.

  11. Global EOS: exploring the 300-ms-latency region

    Science.gov (United States)

    Mascetti, L.; Jericho, D.; Hsu, C.-Y.

    2017-10-01

    EOS, the CERN open-source distributed disk storage system, provides the highperformance storage solution for HEP analysis and the back-end for various work-flows. Recently EOS became the back-end of CERNBox, the cloud synchronisation service for CERN users. EOS can be used to take advantage of wide-area distributed installations: for the last few years CERN EOS uses a common deployment across two computer centres (Geneva-Meyrin and Budapest-Wigner) about 1,000 km apart (∼20-ms latency) with about 200 PB of disk (JBOD). In late 2015, the CERN-IT Storage group and AARNET (Australia) set-up a challenging R&D project: a single EOS instance between CERN and AARNET with more than 300ms latency (16,500 km apart). This paper will report about the success in deploy and run a distributed storage system between Europe (Geneva, Budapest), Australia (Melbourne) and later in Asia (ASGC Taipei), allowing different type of data placement and data access across these four sites.

  12. CLAS: A Novel Communications Latency Based Authentication Scheme

    Directory of Open Access Journals (Sweden)

    Zuochao Dou

    2017-01-01

    Full Text Available We design and implement a novel communications latency based authentication scheme, dubbed CLAS, that strengthens the security of state-of-the-art web authentication approaches by leveraging the round trip network communications latency (RTL between clients and authenticators. In addition to the traditional credentials, CLAS profiles RTL values of clients and uses them to defend against password compromise. The key challenges are (i to prevent RTL manipulation, (ii to alleviate network instabilities, and (iii to address mobile clients. CLAS addresses the first challenge by introducing a novel network architecture, which makes it extremely difficult for attackers to simulate legitimate RTL values. The second challenge is addressed by outlier removal and multiple temporal profiling, while the last challenge is addressed by augmenting CLAS with out-of-band-channels or other authentication schemes. CLAS restricts login to profiled locations while demanding additional information for nonprofiled ones, which highly reduces the attack surface even when the legitimate credentials are compromised. Additionally, unlike many state-of-the-art authentication mechanisms, CLAS is resilient to phishing, pharming, man-in-the-middle, and social engineering attacks. Furthermore, CLAS is transparent to users and incurs negligible overhead. The experimental results show that CLAS can achieve very low false positive and false negative rates.

  13. Avian Habitat Data; Seward Peninsula, Alaska, 2012

    Data.gov (United States)

    Department of the Interior — This data product contains avian habitat data collected on the Seward Peninsula, Alaska, USA, during 21 May – 10 June 2012. We conducted replicated 10-min surveys...

  14. Isolation of avian influenza virus in Texas.

    Science.gov (United States)

    Glass, S E; Naqi, S A; Grumbles, L C

    1981-01-01

    An avian influenza virus with surface antigens similar to those of fowl plague virus (Hav 1 Nav 2) was isolated in 1979 from 2 commercial turkey flocks in Central Texas. Two flocks in contact with these infected flocks developed clinical signs, gross lesions, and seroconversion but yielded no virus. This was the first recorded incidence of clinical avian influenza in Texas turkeys and only the second time that an agent with these surface antigens was isolated from turkeys in U.S.

  15. Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli.

    Science.gov (United States)

    Jørgensen, Steffen L; Kudirkiene, Egle; Li, Lili; Christensen, Jens P; Olsen, John E; Nolan, Lisa; Olsen, Rikke H

    2017-01-01

    Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production economy and welfare worldwide. An almost defining characteristic of avian pathogenic E. coli is the carriage of plasmids, which may encode virulence factors and antibiotic resistance determinates. For the same reason, plasmids of avian pathogenic E. coli have been intensively studied. However, genes encoded by the chromosome may also be important for disease manifestation and antimicrobial resistance. For the E. coli strain APEC_O2 the plasmids have been sequenced and analyzed in several studies, and E. coli APEC_O2 may therefore serve as a reference strain in future studies. Here we describe the chromosomal features of E. coli APEC_O2. E. coli APEC_O2 is a sequence type ST135, has a chromosome of 4,908,820 bp (plasmid removed), comprising 4672 protein-coding genes, 110 RNA genes, and 156 pseudogenes, with an average G + C content of 50.69%. We identified 82 insertion sequences as well as 4672 protein coding sequences, 12 predicated genomic islands, three prophage-related sequences, and two clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. The wildtype strain of E. coli APEC_O2 is resistant towards multiple antimicrobials, however, no (complete) antibiotic resistance genes were present on the chromosome, but a number of genes associated with extra-intestinal disease were identified. Together, the information provided here on E. coli APEC_O2 will assist in future studies of avian pathogenic E. coli strains, in particular regarding strain of E. coli APEC_O2, and aid in the general understanding of the pathogenesis of avian pathogenic E. coli .

  16. Ecology and conservation biology of avian malaria

    Science.gov (United States)

    LaPointe, Dennis A.; Atkinson, Carter T.; Samuel, Michael D.

    2012-01-01

    Avian malaria is a worldwide mosquito-borne disease caused by Plasmodium parasites. These parasites occur in many avian species but primarily affect passerine birds that have not evolved with the parasite. Host pathogenicity, fitness, and population impacts are poorly understood. In contrast to continental species, introduced avian malaria poses a substantial threat to naive birds on Hawaii, the Galapagos, and other archipelagoes. In Hawaii, transmission is maintained by susceptible native birds, competence and abundance of mosquitoes, and a disease reservoir of chronically infected native birds. Although vector habitat and avian communities determine the geographic distribution of disease, climate drives transmission patterns ranging from continuous high infection in warm lowland forests, seasonal infection in midelevation forests, and disease-free refugia in cool high-elevation forests. Global warming is expected to increase the occurrence, distribution, and intensity of avian malaria across this elevational gradient and threaten high-elevation refugia, which is the key to survival of many susceptible Hawaiian birds. Increased temperatures may have already increased global avian malaria prevalence and contributed to an emergence of disease in New Zealand.

  17. Segment scheduling method for reducing 360° video streaming latency

    Science.gov (United States)

    Gudumasu, Srinivas; Asbun, Eduardo; He, Yong; Ye, Yan

    2017-09-01

    360° video is an emerging new format in the media industry enabled by the growing availability of virtual reality devices. It provides the viewer a new sense of presence and immersion. Compared to conventional rectilinear video (2D or 3D), 360° video poses a new and difficult set of engineering challenges on video processing and delivery. Enabling comfortable and immersive user experience requires very high video quality and very low latency, while the large video file size poses a challenge to delivering 360° video in a quality manner at scale. Conventionally, 360° video represented in equirectangular or other projection formats can be encoded as a single standards-compliant bitstream using existing video codecs such as H.264/AVC or H.265/HEVC. Such method usually needs very high bandwidth to provide an immersive user experience. While at the client side, much of such high bandwidth and the computational power used to decode the video are wasted because the user only watches a small portion (i.e., viewport) of the entire picture. Viewport dependent 360°video processing and delivery approaches spend more bandwidth on the viewport than on non-viewports and are therefore able to reduce the overall transmission bandwidth. This paper proposes a dual buffer segment scheduling algorithm for viewport adaptive streaming methods to reduce latency when switching between high quality viewports in 360° video streaming. The approach decouples the scheduling of viewport segments and non-viewport segments to ensure the viewport segment requested matches the latest user head orientation. A base layer buffer stores all lower quality segments, and a viewport buffer stores high quality viewport segments corresponding to the most recent viewer's head orientation. The scheduling scheme determines viewport requesting time based on the buffer status and the head orientation. This paper also discusses how to deploy the proposed scheduling design for various viewport adaptive video

  18. Neural network connectivity and response latency modelled by stochastic processes

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano

    is connected to thousands of other neurons. The rst question is: how to model neural networks through stochastic processes? A multivariate Ornstein-Uhlenbeck process, obtained as a diffusion approximation of a jump process, is the proposed answer. Obviously, dependencies between neurons imply dependencies...... between their spike times. Therefore, the second question is: how to detect neural network connectivity from simultaneously recorded spike trains? Answering this question corresponds to investigate the joint distribution of sequences of rst passage times. A non-parametric method based on copulas...... generation of pikes. When a stimulus is applied to the network, the spontaneous rings may prevail and hamper detection of the effects of the stimulus. Therefore, the spontaneous rings cannot be ignored and the response latency has to be detected on top of a background signal. Everything becomes more dicult...

  19. Latency reversal and viral clearance to cure HIV-1.

    Science.gov (United States)

    Margolis, David M; Garcia, J Victor; Hazuda, Daria J; Haynes, Barton F

    2016-07-22

    Research toward a cure for human immunodeficiency virus type 1 (HIV-1) infection has joined prevention and treatment efforts in the global public health agenda. A major approach to HIV eradication envisions antiretroviral suppression, paired with targeted therapies to enforce the expression of viral antigen from quiescent HIV-1 genomes, and immunotherapies to clear latent infection. These strategies are targeted to lead to viral eradication--a cure for AIDS. Paired testing of latency reversal and clearance strategies has begun, but additional obstacles to HIV eradication may emerge. Nevertheless, there is reason for optimism that advances in long-acting antiretroviral therapy and HIV prevention strategies will contribute to efforts in HIV cure research and that the implementation of these efforts will synergize to markedly blunt the effect of the HIV pandemic on society. Copyright © 2016, American Association for the Advancement of Science.

  20. Iodine intake not radiation is the probable major influence on the morphology, aggressiveness and latency of papillary thyroid carcinomas (PTC)

    International Nuclear Information System (INIS)

    Williams, Dill; Vowler, Sarah; Bogdanova, Tania; Tronko, Nikol; Ito, Masah; Livolsi, Virg; Thomas, Gerry; Demidchik, Evg

    2005-01-01

    Full text: This study set out to investigate whether radiation induced thyroid cancers differ in morphology and aggressiveness from non radiation induced cancers, and whether other factors such as iodine intake are important. Chernobyl-related thyroid carcinomas, almost all PTCs, are reportedly typically morphologically solid, RET-PTC3 positive, and aggressive. We have studied 152 PTCs, 84 Chernobyl related (Chernobyl Tumour Bank), 23 unexposed children from the same area, and 45 from other countries. We quantified morphological changes and invasion, and found no significant differences between age-matched radiation-exposed and unexposed groups from the Chernobyl regions (papillary differentiation 34.3 v 35.2%, invasion 62 v 65 %). Age-matched tumours from Japan, a country with high dietary iodine, showed significantly more well-differentiated papillary architecture (80.8 v 43.3%, p<0.0001) and significantly less invasion (30 v 57 %, p<0.01) than tumours from Chernobyl regions. PTCs from England and Wales, iodine intake intermediate between Japan and the iodine deficient Chernobyl regions, showed intermediate features. We and others have shown that papillary architecture correlates with RET-PTC1 and solid morphology with RET-PTC3; the proportion of RET-PTC3 positive tumours has declined with increasing latency. We have also previously shown that solid morphology in Chernobyl-related PTCs correlates with short latency irrespective of age at exposure. Conclusion: We conclude that in the 19 years since the Chernobyl accident the radiation and non radiation-induced induced papillary carcinomas from the same areas do not differ in morphology and aggressiveness but both differ significantly from tumours from an iodine rich country. We suggest that these features and the surprisingly short latency after Chernobyl compared to other radiation incidents are influenced by the low dietary iodine intake. (author)

  1. Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

    Science.gov (United States)

    Coates, Peter S.; Casazza, Michael L.; Halstead, Brian J.; Fleskes, Joseph P.; Laughlin, James A.

    2011-01-01

    Radar systems designed to detect avian activity at airfields are useful in understanding factors that influence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfield was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was first explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24-hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coefficients) averaged across models and a relatively simple calculation for safety officers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fit. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refine these inference models and improve our understanding of factors that influence avian activity, which is necessary to inform

  2. Fault latency in the memory - An experimental study on VAX 11/780

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1986-01-01

    Fault latency is the time between the physical occurrence of a fault and its corruption of data, causing an error. The measure of this time is difficult to obtain because the time of occurrence of a fault and the exact moment of generation of an error are not known. This paper describes an experiment to accurately study the fault latency in the memory subsystem. The experiment employs real memory data from a VAX 11/780 at the University of Illinois. Fault latency distributions are generated for s-a-0 and s-a-1 permanent fault models. Results show that the mean fault latency of a s-a-0 fault is nearly 5 times that of the s-a-1 fault. Large variations in fault latency are found for different regions in memory. An analysis of a variance model to quantify the relative influence of various workload measures on the evaluated latency is also given.

  3. Avian cholera in Nebraska's Rainwater Basin

    Science.gov (United States)

    Windingstad, R.M.; Hurt, J.J.; Trout, A.K.; Cary, J.

    1984-01-01

    The first report of avian cholera in North America occurred in northwestern Texas in winter 1944 (Quortrup et al. 1946). In 1975, mortality from avian cholera occurred for the first time in waterfowl in the Rainwater Basin of Nebraska when an estimated 25,000 birds died (Zinkl et al. 1977). Avian cholera has continued to cause mortality in wild birds in specific areas of the Basin each spring since. Losses of waterfowl from avian cholera continue to be much greater in some of the wetlands in the western part of the Basin than in the east. Several wetlands in the west have consistently higher mortality and are most often the wetlands where initial mortality is noticed each spring (Figure 1). The establishment of this disease in Nebraska is of considerable concern because of the importance of the Rainwater Basin as a spring staging area for waterfowl migrating to their breeding grounds. The wetlands in this area are on a major migration route used by an estimated 5 to 9 million ducks and several hundred thousand geese. A large portion of the western mid-continental greater white-fronted goose (Anser albifrons) population stage in the Basin each spring. Occasionally, whooping cranes (Grus americana) use these wetlands during migration, and lesser sandhill cranes (Grus canadensis) staging on the nearby Platte River sometimes use wetlands where avian cholera occurs (Anonymous 1981). Our objectives were to determine whether certain water quality variables in the Rainwater Basin differed between areas of high and low avian cholera incidence. These results would then be used for laboratory studies involving the survivability of Pasteurella multocida, the causative bacterium of avian cholera. Those studies will be reported elsewhere.

  4. Integer-valued Lévy processes and low latency financial econometrics

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Pollard, David G.; Shephard, Neil

    Motivated by features of low latency data in financial econometrics we study in detail integervalued Lévy processes as the basis of price processes for high frequency econometrics. We propose using models built out of the difference of two subordinators. We apply these models in practice to low...... latency data for a variety of different types of futures contracts.futures markets, high frequency econometrics, low latency data, negative binomial, Skellam, tempered stable...

  5. Test Operations Procedure (TOP) 02-2-546 Teleoperated Unmanned Ground Vehicle (UGV) Latency Measurements

    Science.gov (United States)

    2017-01-11

    anti - lock brake systems , or self-leveling systems . 2. FACILITIES AND INSTRUMENTATION. 2.1 Facilities. Testing will be conducted at the...This TOP describes procedures for measuring teleoperated system latencies of Unmanned Ground Vehicles (UGVs) for the purpose of analyzing system ...discrete system components or measurements of latency in autonomous systems . 15. SUBJECT TERMS Unmanned Ground Vehicles, Basic Video Latency, End-to

  6. The Viral Protein Tat Can Inhibit the Establishment of HIV-1 Latency

    OpenAIRE

    Donahue, Daniel A.; Kuhl, Björn D.; Sloan, Richard D.; Wainberg, Mark A.

    2012-01-01

    The establishment of HIV-1 latency can result from limiting levels of transcription initiation or elongation factors, restrictive chromatin modifications, transcriptional interference, and insufficient Tat activity. Since the viral protein Tat can counteract many of these factors, we hypothesized that the presence of exogenous Tat during infection might inhibit the establishment of latency. This was explored using a Jurkat model of latency establishment and reactivation. PCR and reverse trans...

  7. Interferon-γ-inducible protein 16 (IFI16) is required for the maintenance of Epstein-Barr virus latency.

    Science.gov (United States)

    Pisano, Gina; Roy, Arunava; Ahmed Ansari, Mairaj; Kumar, Binod; Chikoti, Leela; Chandran, Bala

    2017-11-13

    Epstein-Barr virus (EBV) exhibits both lytic and latent (Lat. I, II, and III) phases in an infected individual. It's during the latent phase of EBV that all EBV-associated cancers, including Burkitt's lymphoma, nasopharyngeal carcinoma and lymphoproliferative disease arise. Interferon-γ-inducible protein 16 (IFI16) is a well-established innate immune sensor and viral transcriptional regulator involved in response to invading DNA viruses. During latency, IFI16 remains in the nucleus, in part bound to the EBV genome; however, neither its role in EBV lytic cycle or latency has been established. Short interfering RNA against IFI16 and IFI16 overexpression were used to identify the role of IFI16 in the maintenance of EBV latency I. We also studied how induction of the lytic cycle affected IFI16 using the EBV positive, latently infected Akata or MUTU-1 cell lines. Akata cells were induced with TPA and MUTU-1 cells with TGF-β up to 96 h and changes in IFI16 protein were analyzed by Western blotting and immunofluorescence microscopy. To assess the mechanism of IFI16 decrease, EBV DNA replication and late lytic transcripts were blocked using the viral DNA polymerase inhibitor phosphonoacetic acid. Knockdown of IFI16 mRNA by siRNA resulted in enhanced levels of EBV lytic gene expression from all temporal gene classes, as well as an increase in the total EBV genome abundance, whereas overexpression of exogenous IFI16 reversed these effects. Furthermore, 96 h after induction of the lytic cycle with either TPA (Akata) or TGF-β (MUTU-1), IFI16 protein levels decreased up to 80% as compared to the EBV-negative cell line BJAB. Reduction in IFI16 was observed in cells expressing EBV lytic envelope glycoprotein. The decreased levels of IFI16 protein do not appear to be dependent on late lytic transcripts of EBV but suggest involvement of the immediate early, early, or a combination of both gene classes. Reduction of IFI16 protein levels following lytic cycle induction, as well

  8. DIVA vaccination strategies for avian influenza virus.

    Science.gov (United States)

    Suarez, David L

    2012-12-01

    Vaccination for both low pathogenicity avian influenza and highly pathogenic avian influenza is commonly used by countries that have become endemic for avian influenza virus, but stamping-out policies are still common for countries with recently introduced disease. Stamping-out policies of euthanatizing infected and at-risk flocks has been an effective control tool, but it comes at a high social and economic cost. Efforts to identify alternative ways to respond to outbreaks without widespread stamping out has become a goal for organizations like the World Organisation for Animal Health. A major issue with vaccination for avian influenza is trade considerations because countries that vaccinate are often considered to be endemic for the disease and they typically lose their export markets. Primarily as a tool to promote trade, the concept of DIVA (differentiate infected from vaccinated animals) has been considered for avian influenza, but the goal for trade is to differentiate vaccinated and not-infected from vaccinated and infected animals because trading partners are unwilling to accept infected birds. Several different strategies have been investigated for a DIVA strategy, but each has advantages and disadvantages. A review of current knowledge on the research and implementation of the DIVA strategy will be discussed with possible ways to implement this strategy in the field. The increased desire for a workable DIVA strategy may lead to one of these ideas moving from the experimental to the practical.

  9. Avian Flu Epidemic 2003: Public health consequences. Executive summary

    NARCIS (Netherlands)

    Bosman A; Mulder YM; Leeuw JRJ de; Meijer A; Du Ry van Beest Holle M; Kamst RA; Velden PG van der; Conyn-van Spaendonck MAE; Koopmans MPG; Ruijten MWMM; Instituut voor Psychotrauma; CIE; MGO; LIS

    2004-01-01

    Executive summary Avian flu epidemic 2003: public health consequences.Risk factors, health, well-being, health care needs and preventive measures during the H7N7 avian flu outbreak control in the Netherlands.An estimated thousand people, possibly more have been infected with avian flu during the

  10. Proceedings of National Avian-Wind Power Planning Meeting IV

    Energy Technology Data Exchange (ETDEWEB)

    NWCC Avian Subcommittee

    2001-05-01

    OAK-B135 The purpose of the fourth meeting was to (1) share research and update research conducted on avian wind interactions (2) identify questions and issues related to the research results, (3) develop conclusions about some avian/wind power issues, and (4) identify questions and issues for future avian research.

  11. Avian metapneumovirus subgroup C infection in chickens, China.

    Science.gov (United States)

    Wei, Li; Zhu, Shanshan; Yan, Xv; Wang, Jing; Zhang, Chunyan; Liu, Shuhang; She, Ruiping; Hu, Fengjiao; Quan, Rong; Liu, Jue

    2013-07-01

    Avian metapneumovirus causes acute respiratory tract infection and reductions in egg production in various avian species. We isolated and characterized an increasingly prevalent avian metapneumovirus subgroup C strain from meat-type commercial chickens with severe respiratory signs in China. Culling of infected flocks could lead to economic consequences.

  12. Avian Metapneumovirus Subgroup C Infection in Chickens, China

    OpenAIRE

    Wei, Li; Zhu, Shanshan; Yan, Xv; Wang, Jing; Zhang, Chunyan; Liu, Shuhang; She, Ruiping; Hu, Fengjiao; Quan, Rong; Liu, Jue

    2013-01-01

    Avian metapneumovirus causes acute respiratory tract infection and reductions in egg production in various avian species. We isolated and characterized an increasingly prevalent avian metapneumovirus subgroup C strain from meat-type commercial chickens with severe respiratory signs in China. Culling of infected flocks could lead to economic consequences.

  13. Deforestation and avian infectious diseases

    Science.gov (United States)

    Sehgal, R. N. M.

    2010-01-01

    In this time of unprecedented global change, infectious diseases will impact humans and wildlife in novel and unknown ways. Climate change, the introduction of invasive species, urbanization, agricultural practices and the loss of biodiversity have all been implicated in increasing the spread of infectious pathogens. In many regards, deforestation supersedes these other global events in terms of its immediate potential global effects in both tropical and temperate regions. The effects of deforestation on the spread of pathogens in birds are largely unknown. Birds harbor many of the same types of pathogens as humans and in addition can spread infectious agents to humans and other wildlife. It is thought that avifauna have gone extinct due to infectious diseases and many are presently threatened, especially endemic island birds. It is clear that habitat degradation can pose a direct threat to many bird species but it is uncertain how these alterations will affect disease transmission and susceptibility to disease. The migration and dispersal of birds can also change with habitat degradation, and thus expose populations to novel pathogens. Some recent work has shown that the results of landscape transformation can have confounding effects on avian malaria, other haemosporidian parasites and viruses. Now with advances in many technologies, including mathematical and computer modeling, genomics and satellite tracking, scientists have tools to further research the disease ecology of deforestation. This research will be imperative to help predict and prevent outbreaks that could affect avifauna, humans and other wildlife worldwide. PMID:20190120

  14. Deforestation and avian infectious diseases.

    Science.gov (United States)

    Sehgal, R N M

    2010-03-15

    In this time of unprecedented global change, infectious diseases will impact humans and wildlife in novel and unknown ways. Climate change, the introduction of invasive species, urbanization, agricultural practices and the loss of biodiversity have all been implicated in increasing the spread of infectious pathogens. In many regards, deforestation supersedes these other global events in terms of its immediate potential global effects in both tropical and temperate regions. The effects of deforestation on the spread of pathogens in birds are largely unknown. Birds harbor many of the same types of pathogens as humans and in addition can spread infectious agents to humans and other wildlife. It is thought that avifauna have gone extinct due to infectious diseases and many are presently threatened, especially endemic island birds. It is clear that habitat degradation can pose a direct threat to many bird species but it is uncertain how these alterations will affect disease transmission and susceptibility to disease. The migration and dispersal of birds can also change with habitat degradation, and thus expose populations to novel pathogens. Some recent work has shown that the results of landscape transformation can have confounding effects on avian malaria, other haemosporidian parasites and viruses. Now with advances in many technologies, including mathematical and computer modeling, genomics and satellite tracking, scientists have tools to further research the disease ecology of deforestation. This research will be imperative to help predict and prevent outbreaks that could affect avifauna, humans and other wildlife worldwide.

  15. Avian infectious bronchitis virus in Africa: a review.

    Science.gov (United States)

    Khataby, Khadija; Fellahi, Siham; Loutfi, Chafiqa; Mustapha, Ennaji Moulay

    2016-06-01

    Infectious bronchitis virus (IBV) is worldwide in distribution, highly infectious, and extremely difficult to control because it has extensive genetic diversity, a short generation time, and a high mutation rate. IBV is a Gammacoronavirus, single-stranded, and positive-sense RNA virus. Avian infectious bronchitis is well studied in European countries with identification of a large number of IBV variants, whereas in African countries epidemiological and scientific data are poor and not updated. However, previous studies reported that an IBV variant continues to appear regularly in Africa, as currently described in Morocco. No cross-protection between IBV strains was reported, some being unique to a particular country, others having a more general distribution. This review aims to provide a general overview on IB disease distribution in African countries and an update on the available studies of IBV variants in each country.

  16. Nocturnal Rapid Eye Movement Sleep Latency for Identifying Patients With Narcolepsy/Hypocretin Deficiency

    Science.gov (United States)

    Andlauer, Olivier; Moore, Hyatt; Jouhier, Laura; Drake, Christopher; Peppard, Paul E.; Han, Fang; Hong, Seung-Chul; Poli, Francesca; Plazzi, Giuseppe; O’Hara, Ruth; Haffen, Emmanuel; Roth, Thomas; Young, Terry; Mignot, Emmanuel

    2014-01-01

    IMPORTANCE Narcolepsy, a disorder associated with HLA-DQB1*06:02 and caused by hypocretin (orexin) deficiency, is diagnosed using the Multiple Sleep Latency Test (MSLT) following nocturnal polysomnography (NPSG). In many patients, a short rapid eye movement sleep latency (REML) during the NPSG is also observed but not used diagnostically. OBJECTIVE To determine diagnostic accuracy and clinical utility of nocturnal REML measures in narcolepsy/hypocretin deficiency. DESIGN, SETTING, AND PARTICIPANTS Observational study using receiver operating characteristic curves for NPSG REML and MSLT findings (sleep studies performed between May 1976 and September 2011 at university medical centers in the United States, China, Korea, and Europe) to determine optimal diagnostic cutoffs for narcolepsy/hypocretin deficiency compared with different samples: controls, patients with other sleep disorders, patients with other hypersomnias, and patients with narcolepsy with normal hypocretin levels. Increasingly stringent comparisons were made. In a first comparison, 516 age- and sex-matched patients with narcolepsy/hypocretin deficiency were selected from 1749 patients and compared with 516 controls. In a second comparison, 749 successive patients undergoing sleep evaluation for any sleep disorders (low pretest probability for narcolepsy) were compared within groups by final diagnosis of narcolepsy/hypocretin deficiency. In the third comparison, 254 patients with a high pretest probability of having narcolepsy were compared within group by their final diagnosis. Finally, 118 patients with narcolepsy/hypocretin deficiency were compared with 118 age- and sex-matched patients with a diagnosis of narcolepsy but with normal hypocretin levels. MAIN OUTCOME AND MEASURES Sensitivity and specificity of NPSG REML and MSLT as diagnostic tests for narcolepsy/hypocretin deficiency. This diagnosis was defined as narcolepsy associated with cataplexy plus HLA-DQB1*06:02 positivity (no cerebrospinal

  17. Nocturnal rapid eye movement sleep latency for identifying patients with narcolepsy/hypocretin deficiency.

    Science.gov (United States)

    Andlauer, Olivier; Moore, Hyatt; Jouhier, Laura; Drake, Christopher; Peppard, Paul E; Han, Fang; Hong, Seung-Chul; Poli, Francesca; Plazzi, Giuseppe; O'Hara, Ruth; Haffen, Emmanuel; Roth, Thomas; Young, Terry; Mignot, Emmanuel

    2013-07-01

    Narcolepsy, a disorder associated with HLA-DQB1*06:02 and caused by hypocretin (orexin) deficiency, is diagnosed using the Multiple Sleep Latency Test (MSLT) following nocturnal polysomnography (NPSG). In many patients, a short rapid eye movement sleep latency (REML) during the NPSG is also observed but not used diagnostically. To determine diagnostic accuracy and clinical utility of nocturnal REML measures in narcolepsy/hypocretin deficiency. Observational study using receiver operating characteristic curves for NPSG REML and MSLT findings (sleep studies performed between May 1976 and September 2011 at university medical centers in the United States, China, Korea, and Europe) to determine optimal diagnostic cutoffs for narcolepsy/hypocretin deficiency compared with different samples: controls, patients with other sleep disorders, patients with other hypersomnias, and patients with narcolepsy with normal hypocretin levels. Increasingly stringent comparisons were made. In a first comparison, 516 age- and sex-matched patients with narcolepsy/hypocretin deficiency were selected from 1749 patients and compared with 516 controls. In a second comparison, 749 successive patients undergoing sleep evaluation for any sleep disorders (low pretest probability for narcolepsy) were compared within groups by final diagnosis of narcolepsy/hypocretin deficiency. In the third comparison, 254 patients with a high pretest probability of having narcolepsy were compared within group by their final diagnosis. Finally, 118 patients with narcolepsy/hypocretin deficiency were compared with 118 age- and sex-matched patients with a diagnosis of narcolepsy but with normal hypocretin levels. Sensitivity and specificity of NPSG REML and MSLT as diagnostic tests for narcolepsy/hypocretin deficiency. This diagnosis was defined as narcolepsy associated with cataplexy plus HLA-DQB1*06:02 positivity (no cerebrospinal fluid hypocretin-1 results available) or narcolepsy with documented low (≤ 110 pg

  18. Latencies in BOLD response during visual attention processes.

    Science.gov (United States)

    Kellermann, Thilo; Reske, Martina; Jansen, Andreas; Satrapi, Peyman; Shah, N Jon; Schneider, Frank; Habel, Ute

    2011-04-22

    One well-investigated division of attentional processes focuses on alerting, orienting and executive control, which can be assessed applying the attentional network test (ANT). The goal of the present study was to add further knowledge about the temporal dynamics of relevant neural correlates. As a right hemispheric dominance for alerting and orienting has previously been reported for intrinsic but not for phasic alertness, we additionally addressed a potential impact of this lateralization of attention by employing a lateralized version of the ANT, capturing phasic alertness processes. Sixteen healthy subjects underwent event-related functional magnetic resonance imaging (fMRI) while performing the ANT. Analyses of BOLD magnitude replicated the engagement of a fronto-parietal network in the attentional subsystems. The amplitudes of the attentional contrasts interacted with visual field presentation in the sense that the thalamus revealed a greater involvement for spatially cued items presented in the left visual field. Comparisons of BOLD latencies in visual cortices, first, verified faster BOLD responses following contra-lateral stimulus presentation. Second and more importantly, we identified attention-modulated activation in secondary visual and anterior cingulate cortices. Results are discussed in terms of bottom-up and lateralization processes. Although intrinsic and phasic alertness are distinct cognitive processes, we propose that neural substrates of intrinsic alertness may be accessed by phasic alertness provided that the attention-dominant (i.e., the right) hemisphere is activated directly by a warning stimulus. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. The latency complex: the dead hand of anti-development.

    Science.gov (United States)

    Proner, Barry D

    2017-09-01

    It is common knowledge that the same phenomena can be viewed in a variety of ways. This paper considers the implications of a constellation observed in some adult patients who have increasingly reminded the author of some of the children of latency age with whom he has also worked. In the literature these patients may also have been thought about in terms of 'defences of the self' (Fordham), patients who are 'difficult to reach' (Joseph), 'psychic retreats' (Steiner), and those who make 'attacks on linking' (Bion). They may equally be considered in terms of schizoid, narcissistic or borderline personalities, or as showing features on the autistic spectrum, such as mindlessness and extreme obsessionality. Writers such as Helene Deutsch with her concept of an 'as-if personality', Winnicott with his 'false self', and Rosenfeld, discussing the split-off parts of the personality in narcissistic patients, have also offered much to think about in their consideration of some of these phenomena. This paper proposes yet another vertex - the author's own imaginative conjecture - that is by no means mutually exclusive of any of these others. © 2017, The Society of Analytical Psychology.

  20. Origin and evolution of avian microchromosomes.

    Science.gov (United States)

    Burt, D W

    2002-01-01

    The origin of avian microchromosomes has long been the subject of much speculation and debate. Microchromosomes are a universal characteristic of all avian species and many reptilian karyotypes. The typical avian karyotype contains about 40 pairs of chromosomes and usually 30 pairs of small to tiny microchromosomes. This characteristic karyotype probably evolved 100-250 million years ago. Once the microchromosomes were thought to be a non-essential component of the avian genome. Recent work has shown that even though these chromosomes represent only 25% of the genome; they encode 50% of the genes. Contrary to popular belief, microchromosomes are present in a wide range of vertebrate classes, spanning 400-450 million years of evolutionary history. In this paper, comparative gene mapping between the genomes of chicken, human, mouse and zebrafish, has been used to investigate the origin and evolution of avian microchromosomes during this period. This analysis reveals evidence for four ancient syntenies conserved in fish, birds and mammals for over 400 million years. More than half, if not all, microchromosomes may represent ancestral syntenies and at least ten avian microchromosomes are the product of chromosome fission. Birds have one of the smallest genomes of any terrestrial vertebrate. This is likely to be the product of an evolutionary process that minimizes the DNA content (mostly through the number of repeats) and maximizes the recombination rate of microchromosomes. Through this process the properties (GC content, DNA and repeat content, gene density and recombination rate) of microchromosomes and macrochromosomes have diverged to create distinct chromosome types. An ancestral genome for birds likely had a small genome, low in repeats and a karyotype with microchromosomes. A "Fission-Fusion Model" of microchromosome evolution based on chromosome rearrangement and minimization of repeat content is discussed. Copyright 2002 S. Karger AG, Basel

  1. No file left behind - monitoring transfer latencies in PhEDEx

    International Nuclear Information System (INIS)

    Chwalek, T; Egeland, R; Gutsche, O; Huang, C-H; Kaselis, R; Klute, M; Magini, N; Moscato, F; Piperov, S; Ratnikova, N; Rossman, P; Sanchez-Hernandez, A; Sartirana, A; Wildish, T; Yang, M; Xie, S

    2012-01-01

    The CMS experiment has to move Petabytes of data among dozens of computing centres with low latency in order to make efficient use of its resources. Transfer operations are well established to achieve the desired level of throughput, but operators lack a system to identify early on transfers that will need manual intervention to reach completion. File transfer latencies are sensitive to the underlying problems in the transfer infrastructure, and their measurement can be used as prompt trigger for preventive actions. For this reason, PhEDEx, the CMS transfer management system, has recently implemented a monitoring system to measure the transfer latencies at the level of individual files. For the first time now, the system can predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies early, and correct the issues while the transfer is still in progress. Statistics are aggregated for blocks of files, recording a historical log to monitor the long-term evolution of transfer latencies, which are used as cumulative metrics to evaluate the performance of the transfer infrastructure, and to plan the global data placement strategy. In this contribution, we present the typical patterns of transfer latencies that may be identified with the latency monitor, and we show how we are able to detect the sources of latency arising from the underlying infrastructure (such as stuck files) which need operator intervention.

  2. Subtle role of latency for information diffusion in online social networks

    International Nuclear Information System (INIS)

    Xiong Fei; Wang Xi-Meng; Cheng Jun-Jun

    2016-01-01

    Information diffusion in online social networks is induced by the event of forwarding information for users, and latency exists widely in user spreading behaviors. Little work has been done to reveal the effect of latency on the diffusion process. In this paper, we propose a propagation model in which nodes may suspend their spreading actions for a waiting period of stochastic length. These latent nodes may recover their activity again. Meanwhile, the mechanism of forwarding information is also introduced into the diffusion model. Mean-field analysis and numerical simulations indicate that our model has three nontrivial results. First, the spreading threshold does not correlate with latency in neither homogeneous nor heterogeneous networks, but depends on the spreading and refractory parameter. Furthermore, latency affects the diffusion process and changes the infection scale. A large or small latency parameter leads to a larger final diffusion extent, but the intrinsic dynamics is different. Large latency implies forwarding information rapidly, while small latency prevents nodes from dropping out of interactions. In addition, the betweenness is a better descriptor to identify influential nodes in the model with latency, compared with the coreness and degree. These results are helpful in understanding some collective phenomena of the diffusion process and taking measures to restrain a rumor in social networks. (paper)

  3. MAC Layer Enhancements for Ultra-Reliable Low-Latency Communications in Cellular Networks

    DEFF Research Database (Denmark)

    Gerardino, Guillermo Andrés Pocovi; Alvarez, Beatriz Soret; Pedersen, Klaus I.

    2017-01-01

    Ultra-reliable low-latency communications (URLLC) entail the transmission of sporadic and small packets, with low latency and very high reliability. Among many potential areas of optimization for URLLC, the problems of large delays during HARQ retransmissions, and inaccurate link adaptation as a ...

  4. Minimum waste scheduling of dynamic variable-latency and non-manifest fuctional units

    NARCIS (Netherlands)

    Mansour, O.; Molenkamp, Egbert; Krol, Th.

    2002-01-01

    In this paper we address the problem of scheduling algorithms embodied with a mixture of nonmanifest-loops [1], variable-latency and fixed-latency units [2], [3] for high throughput DSP-applications. Nonmanifest loops are loops where the number of iterations needed for a calculation is data

  5. Low Latency Audio Video: Potentials for Collaborative Music Making through Distance Learning

    Science.gov (United States)

    Riley, Holly; MacLeod, Rebecca B.; Libera, Matthew

    2016-01-01

    The primary purpose of this study was to examine the potential of LOw LAtency (LOLA), a low latency audio visual technology designed to allow simultaneous music performance, as a distance learning tool for musical styles in which synchronous playing is an integral aspect of the learning process (e.g., jazz, folk styles). The secondary purpose was…

  6. Long-latency auditory evoked potentials with verbal and nonverbal stimuli,

    Directory of Open Access Journals (Sweden)

    Sheila Jacques Oppitz

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. OBJECTIVE: To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. METHODS: A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000 Hz - frequent and 4000 Hz - rare; and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare. RESULTS: Considering the component N2 for tone burst, the lowest latency found was 217.45 ms for the BA/DI stimulus; the highest latency found was 256.5 ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340 ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. CONCLUSION: There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude.

  7. Measuring the Latency of an Augmented Reality System for Robot-Assisted Minimally Invasive Surgery

    DEFF Research Database (Denmark)

    Jørgensen, Martin Kibsgaard; Kraus, Martin

    2017-01-01

    Minimal latency is important for augmented reality systems and teleoperation interfaces as even small increases in latency can affect user performance. Previously, we have developed an augmented reality system that can overlay stereoscopic video streams with computer graphics in order to improve...

  8. Ribosomal RNA gene functioning in avian oogenesis.

    Science.gov (United States)

    Koshel, Elena; Galkina, Svetlana; Saifitdinova, Alsu; Dyomin, Alexandr; Deryusheva, Svetlana; Gaginskaya, Elena

    2016-12-01

    Despite long-term exploration into ribosomal RNA gene functioning during the oogenesis of various organisms, many intriguing problems remain unsolved. In this review, we describe nucleolus organizer region (NOR) activity in avian oocytes. Whereas oocytes from an adult avian ovary never reveal the formation of the nucleolus in the germinal vesicle (GV), an ovary from juvenile birds possesses both nucleolus-containing and non-nucleolus-containing oocytes. The evolutionary diversity of oocyte NOR functioning and the potential non-rRNA-related functions of the nucleolus in oocytes are also discussed.

  9. Subjective reports versus objective measurement of sleep latency and sleep duration in pregnancy.

    Science.gov (United States)

    Wilson, Danielle L; Fung, Alison; Walker, Susan P; Barnes, Maree

    2013-01-01

    This study compared self-reported sleep latency (SL) and total sleep time (TST) to objective measures on polysomnography (PSG) during pregnancy. Thirty-three women in the third trimester (T3) of pregnancy, 16 women in the first trimester (T1) of pregnancy, and 15 non-pregnant women underwent overnight PSG, and shortly after awakening reported their perceived SL and TST. Results showed that, on average, the T3 group slightly overestimated their TSTs, whereas the T1 and non-pregnant groups underestimated TSTs when compared with objective measurement. All groups overestimated SL, and perceived SL was closest to the first epoch of 10 min of uninterrupted sleep or the first epoch of slow-wave sleep, rather than the first epoch of sleep (the current definition used for diagnostic sleep studies). The wide variation in discrepancies between estimation and PSG measurement for both TST and SL shows that self-reports made by both pregnant and non-pregnant women tend to be unreliable, which has important implications both clinically and for the many studies based on self-reported sleep patterns in pregnancy.

  10. Latency Analysis of Systems with Multiple Interfaces for Ultra-Reliable M2M Communication

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Popovski, Petar

    2016-01-01

    One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms of latency and reliability of such an integr......One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms of latency and reliability...... of such an integrated communication system, we propose an analysis framework that combines traditional reliability models with technology-specific latency probability distributions. In our proposed model we demonstrate how failure correlation between technologies can be taken into account. We show for the considered...

  11. Epstein-Barr virus latency type and spontaneous reactivation predict lytic induction levels.

    Science.gov (United States)

    Phan, An T; Fernandez, Samantha G; Somberg, Jessica J; Keck, Kristin M; Miranda, Jj L

    2016-05-20

    The human Epstein-Barr virus (EBV) evades the immune system by entering a transcriptionally latent phase in B cells. EBV in tumor cells expresses distinct patterns of genes referred to as latency types. Viruses in tumor cells also display varying levels of lytic transcription resulting from spontaneous reactivation out of latency. We measured this dynamic range of lytic transcription with RNA deep sequencing and observed no correlation with EBV latency types among genetically different viruses, but type I cell lines reveal more spontaneous reactivation than isogenic type III cultures. We further determined that latency type and spontaneous reactivation levels predict the relative amount of induced reactivation generated by cytotoxic chemotherapy drugs. Our work has potential implications for personalizing medicine against EBV-transformed malignancies. Identifying latency type or measuring spontaneous reactivation may provide predictive power in treatment contexts where viral production should be either avoided or coerced. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Short philtrum

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003302.htm Short philtrum To use the sharing features on this page, please enable JavaScript. A short philtrum is a shorter than normal distance between ...

  13. The effect of monitor raster latency on VEPs, ERPs and Brain-Computer Interface performance.

    Science.gov (United States)

    Nagel, Sebastian; Dreher, Werner; Rosenstiel, Wolfgang; Spüler, Martin

    2018-02-01

    Visual neuroscience experiments and Brain-Computer Interface (BCI) control often require strict timings in a millisecond scale. As most experiments are performed using a personal computer (PC), the latencies that are introduced by the setup should be taken into account and be corrected. As a standard computer monitor uses a rastering to update each line of the image sequentially, this causes a monitor raster latency which depends on the position, on the monitor and the refresh rate. We technically measured the raster latencies of different monitors and present the effects on visual evoked potentials (VEPs) and event-related potentials (ERPs). Additionally we present a method for correcting the monitor raster latency and analyzed the performance difference of a code-modulated VEP BCI speller by correcting the latency. There are currently no other methods validating the effects of monitor raster latency on VEPs and ERPs. The timings of VEPs and ERPs are directly affected by the raster latency. Furthermore, correcting the raster latency resulted in a significant reduction of the target prediction error from 7.98% to 4.61% and also in a more reliable classification of targets by significantly increasing the distance between the most probable and the second most probable target by 18.23%. The monitor raster latency affects the timings of VEPs and ERPs, and correcting resulted in a significant error reduction of 42.23%. It is recommend to correct the raster latency for an increased BCI performance and methodical correctness. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. In vivo expression of human cytomegalovirus (HCMV) microRNAs during latency.

    Science.gov (United States)

    Meshesha, Mesfin K; Bentwich, Zvi; Solomon, Semaria A; Avni, Yonat Shemer

    2016-01-01

    Viral encoded microRNAs play key roles in regulating gene expression and the life cycle of human herpes viruses. Latency is one of the hallmarks of the human cytomegalovirus (HCMV or HHV5) life cycle, and its control may have immense practical applications. The present study aims to identify HCMV encoded microRNAs during the latency phase of the virus. We used a highly sensitive real time PCR (RTPCR) assay that involves a pre-amplification step before RTPCR. It can detect HCMV encoded microRNAs (miRNAs) during latency in purified monocytes and PBMCs from HCMV IgG positive donors and in latently infected monocytic THP-1 cell lines. During the latency phase, only eight HCMV encoded microRNAs were detected in PBMCs, monocytes and in the THP-1 cells. Five originated from the UL region of the virus genome and three from the US region. Reactivation of the virus from latency, in monocytes obtained from the same donor, using dexamethasone restored the expression of all known HCMV encoded miRNAs including those that were absent during latency. We observed a shift in the abundance of the two arms of mir-US29 between the productive and latency stages of the viral life cycle, suggesting that the star "passenger" form of this microRNA is preferentially expressed during latency. As a whole, our study demonstrates that HCMV expresses during the latency phase, both in vivo and in vitro, only a subset of its microRNAs, which may indicate that they play an important role in maintenance and reactivation of latency. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Extravehicular Activity Operations Concepts Under Communication Latency and Bandwidth Constraints

    Science.gov (United States)

    Beaton, Kara H.; Chappell, Steven P.; Abercromby, Andrew F. J.; Miller, Matthew J.; Nawotniak, Shannon Kobs; Hughes, Scott; Brady, Allyson; Lim, Darlene S. S.

    2017-01-01

    The Biologic Analog Science Associated with Lava Terrains (BASALT) project is a multi-year program dedicated to iteratively develop, implement, and evaluate concepts of operations (ConOps) and supporting capabilities intended to enable and enhance human scientific exploration of Mars. This pa-per describes the planning, execution, and initial results from the first field deployment, referred to as BASALT-1, which consisted of a series of 10 simulated extravehicular activities (EVAs) on volcanic flows in Idaho's Craters of the Moon (COTM) National Monument. The ConOps and capabilities deployed and tested during BASALT-1 were based on previous NASA trade studies and analog testing. Our primary research question was whether those ConOps and capabilities work acceptably when performing real (non-simulated) biological and geological scientific exploration under 4 different Mars-to-Earth communication conditions: 5 and 15 min one-way light time (OWLT) communication latencies and low (0.512 Mb/s uplink, 1.54 Mb/s downlink) and high (5.0 Mb/s uplink, 10.0 Mb/s downlink) bandwidth conditions representing the lower and higher limits of technical communication capabilities currently proposed for future human exploration missions. The synthesized results of BASALT-1 with respect to the ConOps and capabilities assessment were derived from a variety of sources, including EVA task timing data, network analytic data, and subjective ratings and comments regarding the scientific and operational acceptability of the ConOp and the extent to which specific capabilities were enabling and enhancing, and are presented here. BASALT-1 established preliminary findings that baseline ConOp, software systems, and communication protocols were scientifically and operationally acceptable with minor improvements desired by the "Mars" extravehicular (EV) and intravehicular (IV) crewmembers, but unacceptable with improvements required by the "Earth" Mission Support Center. These data will provide a

  16. Effects of drought on avian community structure

    Science.gov (United States)

    Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Curtis H. Flather; Patrick D. Culbert; Brian D. Wardlow; Volker C. Radeloff

    2010-01-01

    Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioural traits, what time periods and indicators of drought are most...

  17. Serological diagnosis of avian influenza in poultry

    DEFF Research Database (Denmark)

    Comin, Arianna; Toft, Nils; Stegeman, Arjan

    2013-01-01

    Background The serological diagnosis of avian influenza (AI) can be performed using different methods, yet the haemagglutination inhibition (HI) test is considered the gold standard' for AI antibody subtyping. Although alternative diagnostic assays have been developed, in most cases, their accuracy...

  18. New Avian Hepadnavirus in Palaeognathous Bird, Germany

    NARCIS (Netherlands)

    Jo, Wendy K; Pfankuche, Vanessa M; Petersen, Henning; Frei, Samuel; Kummrow, Maya; Lorenzen, Stephan; Ludlow, Martin; Metzger, Julia; Baumgärtner, Wolfgang; Osterhaus, Albert; van der Vries, Erhard

    2017-01-01

    In 2015, we identified an avian hepatitis B virus associated with hepatitis in a group of captive elegant-crested tinamous (Eudromia elegans) in Germany. The full-length genome of this virus shares <76% sequence identity with other avihepadnaviruses. The virus may therefore be considered a new

  19. Avian Disease & Oncology Lab (ADOL) Research Update

    Science.gov (United States)

    Employing Genomics, Epigenetics, and Immunogenetics to Control Diseases Induced by Avian Tumor Viruses - Gene expression is a major factor accounting for phenotypic variation. Taking advantage of allele-specific expression (ASE) screens, we found the use of genetic markers was superior to traditiona...

  20. Viral vectors for avian influenza vaccines

    Science.gov (United States)

    Prior to 2003, vaccines against avian influenza (AI) had limited, individual country or regional use in poultry. In late 2003, H5N1 high pathogenicity (HP) AI spread from China to multiple Southeast Asian countries, and to Europe during 2005 and Africa during 2006, challenging governments and all p...

  1. the Avian Park Service Learning Centre story

    African Journals Online (AJOL)

    The Ukwanda Centre for Rural Health (UCRH) opened in 2001, followed 10 years later by the establishment of the Ukwanda Rural Clinical School in one of the rural health districts of the Western Cape. This paper relates the journey of the Faculty with the underserviced community of Avian Park through the provision of ...

  2. Presumptive diagnosis of Avian encephalomyelitis in Japanese ...

    African Journals Online (AJOL)

    A report of Avian encephalomyelitis outbreak in two flocks of adult Japanese quail is presented. High mortalities, tremor, ataxia and lateral recumbency were the prominent clinical signs observed. Absence of gross pathology and microscopic lesions of gliosis, neuronal degeneration, meningitis, congested blood vessel with ...

  3. The genetics and evolution of avian migration

    NARCIS (Netherlands)

    Pulido, F.

    2007-01-01

    One of the characteristics of avian migration is its variability within and among species. Variation in migratory behavior, and in physiological and morphological adaptations to migration, is to a large extent due to genetic differences. Comparative studies suggest that migratory behavior has

  4. Solar activity affects avian timing of reproduction

    NARCIS (Netherlands)

    Visser, M.E.; Sanz, J.J.

    2009-01-01

    Avian timing of reproduction is strongly affected by ambient temperature. Here we show that there is an additional effect of sunspots on laying date, from five long-term population studies of great and blue tits (Parus major and Cyanistes caeruleus), demonstrating for the first time that solar

  5. Vocal communication in an avian hybrid zone

    NARCIS (Netherlands)

    Hartog, Paula Maria den

    2008-01-01

    Avian vocalizations function in mate attraction and territorial defence. Vocalizations can act as behavioural barriers and play an important role in speciation processes. Hybrid zones illustrate behavioural barriers are not always impermeable and provide a natural laboratory to examine the role of

  6. Fossil avian eggshell preserves ancient DNA

    DEFF Research Database (Denmark)

    Oskam, Charlotte L; Haile, James Seymour; McLay, Emma

    2010-01-01

    Owing to exceptional biomolecule preservation, fossil avian eggshell has been used extensively in geochronology and palaeodietary studies. Here, we show, to our knowledge, for the first time that fossil eggshell is a previously unrecognized source of ancient DNA (aDNA). We describe the successful...

  7. Measuring Steroid Hormones in Avian Eggs

    NARCIS (Netherlands)

    Engelhardt, Nikolaus von; Groothuis, Ton G.G.

    2005-01-01

    Avian eggs contain substantial levels of various hormones of maternal origin and have recently received a lot of interest, mainly from behavioral ecologists. These studies strongly depend on the measurement of egg hormone levels, but the method of measuring these levels has received little

  8. Measuring steroid hormones in avian eggs

    NARCIS (Netherlands)

    Von Engelhardt, Nikolaus; Groothuis, Ton G. G.; Bauchinger, U; Goymann, W; JenniEiermann, S

    2005-01-01

    Avian eggs contain substantial levels of various hormones of maternal origin and have recently received a lot of interest, mainly from behavioral ecologists. These studies strongly depend on the measurement of egg hormone levels, but the method of measuring these levels has received little

  9. Trial latencies estimation of event-related potentials in EEG by means of genetic algorithms

    Science.gov (United States)

    Da Pelo, P.; De Tommaso, M.; Monaco, A.; Stramaglia, S.; Bellotti, R.; Tangaro, S.

    2018-04-01

    Objective. Event-related potentials (ERPs) are usually obtained by averaging thus neglecting the trial-to-trial latency variability in cognitive electroencephalography (EEG) responses. As a consequence the shape and the peak amplitude of the averaged ERP are smeared and reduced, respectively, when the single-trial latencies show a relevant variability. To date, the majority of the methodologies for single-trial latencies inference are iterative schemes providing suboptimal solutions, the most commonly used being the Woody’s algorithm. Approach. In this study, a global approach is developed by introducing a fitness function whose global maximum corresponds to the set of latencies which renders the trial signals most aligned as possible. A suitable genetic algorithm has been implemented to solve the optimization problem, characterized by new genetic operators tailored to the present problem. Main results. The results, on simulated trials, showed that the proposed algorithm performs better than Woody’s algorithm in all conditions, at the cost of an increased computational complexity (justified by the improved quality of the solution). Application of the proposed approach on real data trials, resulted in an increased correlation between latencies and reaction times w.r.t. the output from RIDE method. Significance. The above mentioned results on simulated and real data indicate that the proposed method, providing a better estimate of single-trial latencies, will open the way to more accurate study of neural responses as well as to the issue of relating the variability of latencies to the proper cognitive and behavioural correlates.

  10. Low-Latency Science Exploration of Planetary Bodies: How ISS Might Be Used as Part of a Low-Latency Analog Campaign for Human Exploration

    Science.gov (United States)

    Thronson, Harley; Valinia, Azita; Bleacher, Jacob; Eigenbrode, Jennifer; Garvin, Jim; Petro, Noah

    2014-01-01

    We suggest that the International Space Station be used to examine the application and validation of low-latency telepresence for surface exploration from space as an alternative, precursor, or potentially as an adjunct to astronaut "boots on the ground." To this end, controlled experiments that build upon and complement ground-based analog field studies will be critical for assessing the effects of different latencies (0 to 500 milliseconds), task complexity, and alternate forms of feedback to the operator. These experiments serve as an example of a pathfinder for NASA's roadmap of missions to Mars with low-latency telerobotic exploration as a precursor to astronaut's landing on the surface to conduct geological tasks.

  11. Auditory Brain-Stem and Middle-and Long-Latency Evoked Potentials in Coma

    OpenAIRE

    Rosenberg, C; Wogensen, K; Starr, A

    1984-01-01

    Twenty-five patients in coma, each with a Glascow Coma Scale measure less than or equal to five, were studied within the first three days of hospitalization with auditory brain-stem and middle- and long-latency evoked potentials. Survival was related to the simultaneous preservation of long- and middle-latency and brain-stem evoked potentials. The preservation of just middle-latency and/or brain-stem components did not correlate with survival. However, if the group of patients in coma due to ...

  12. Latency and Jitter Analysis for IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    Sungkwan Youm

    2013-01-01

    Full Text Available This paper presents a numerical analysis of latency and jitter for IEEE 802.11e wireless local area networks (WLANs in a saturation condition, by using a Markov model. We use this model to explicate how the enhanced distributed coordination function (EDCF differentiates classes of service and to characterize the probability distribution of the medium access control (MAC layer packet latency and jitter, on which the quality of the voice over Internet protocol (VoIP calls is dependent. From the proposed analytic model, we can estimate the available number of nodes determining the system performance, in order to satisfy user demands on the latency and jitter.

  13. A Scheduling Discipline for Latency and Bandwidth Guarantees in Asynchronous Network-on-Chip

    DEFF Research Database (Denmark)

    Bjerregaard, Tobias; Sparsø, Jens

    2005-01-01

    Guaranteed services (GS) are important in that they provide predictability in the complex dynamics of shared communication structures. This paper discusses the implementation of GS in asynchronous Network-on-Chip. We present a novel scheduling discipline called Asynchronous Latency Guarantee (ALG......) scheduling, which provides latency and bandwidth guarantees in accessing a shared media, e.g. a physical link shared between a number of virtual channels. ALG overcomes the drawbacks of existing scheduling disciplines, in particular the coupling between latency and bandwidth guarantees. A 0.12 &956;m CMOS...

  14. Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

    for some of the HI listeners. The behavioral auditory-filter bandwidths accounted for the across-listener variability in the ABR latencies: Cochlear response time decreased with increasing filter bandwidth, consistent with linear-system theory. The results link cochlear response time and frequency...... response times. For the same listeners, auditory-filter bandwidths at 2 kHz were estimated using a behavioral notched-noise masking paradigm. Generally, shorter derived-band latencies were observed for the HI than for the NH listeners. Only at low click sensation levels, prolonged latencies were obtained...

  15. Systematic analysis of transcription start sites in avian development.

    Directory of Open Access Journals (Sweden)

    Marina Lizio

    2017-09-01

    Full Text Available Cap Analysis of Gene Expression (CAGE in combination with single-molecule sequencing technology allows precision mapping of transcription start sites (TSSs and genome-wide capture of promoter activities in differentiated and steady state cell populations. Much less is known about whether TSS profiling can characterize diverse and non-steady state cell populations, such as the approximately 400 transitory and heterogeneous cell types that arise during ontogeny of vertebrate animals. To gain such insight, we used the chick model and performed CAGE-based TSS analysis on embryonic samples covering the full 3-week developmental period. In total, 31,863 robust TSS peaks (>1 tag per million [TPM] were mapped to the latest chicken genome assembly, of which 34% to 46% were active in any given developmental stage. ZENBU, a web-based, open-source platform, was used for interactive data exploration. TSSs of genes critical for lineage differentiation could be precisely mapped and their activities tracked throughout development, suggesting that non-steady state and heterogeneous cell populations are amenable to CAGE-based transcriptional analysis. Our study also uncovered a large set of extremely stable housekeeping TSSs and many novel stage-specific ones. We furthermore demonstrated that TSS mapping could expedite motif-based promoter analysis for regulatory modules associated with stage-specific and housekeeping genes. Finally, using Brachyury as an example, we provide evidence that precise TSS mapping in combination with Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR-on technology enables us, for the first time, to efficiently target endogenous avian genes for transcriptional activation. Taken together, our results represent the first report of genome-wide TSS mapping in birds and the first systematic developmental TSS analysis in any amniote species (birds and mammals. By facilitating promoter-based molecular analysis and genetic

  16. Modeling Adenovirus Latency in Human Lymphocyte Cell Lines ▿ †

    OpenAIRE

    Zhang, Yange; Huang, Wen; Ornelles, David A.; Gooding, Linda R.

    2010-01-01

    Species C adenovirus establishes a latent infection in lymphocytes of the tonsils and adenoids. To understand how this lytic virus is maintained in these cells, four human lymphocytic cell lines that support the entire virus life cycle were examined. The T-cell line Jurkat ceased proliferation and died shortly after virus infection. BJAB, Ramos (B cells), and KE37 (T cells) continued to divide at nearly normal rates while replicating the virus genome. Viral genome numbers peaked and then decl...

  17. Effects of Precommercial Thinning and Midstory Control on Avian and Small Mammal Communities during Longleaf Pine Savanna Restoration.

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Vanessa R [Abraham Baldwin Agricultural College; Kilgo, John C [USDA Forest Service, Southern Research Station

    2015-01-01

    Abstract - Restoring longleaf pine (Pinus palustris Mill.) savanna is a goal of many southern land managers, and longleaf plantations may provide a mechanism for savanna restoration. However, the effects of silvicultural treatments used in the management of longleaf pine plantations on wildlife communities are relatively unknown. Beginning in 1994, we examined effects of longleaf pine restoration with plantation silviculture on avian and small mammal communities using four treatments in four 8- to 11- year-old plantations within the Savannah River Site in South Carolina. Treatments included prescribed burning every 3 to 5 years, plus: (1) no additional treatment (burn-only control); (2) precommercial thinning; (3) non-pine woody control with herbicides; and (4) combined thinning and woody control. We surveyed birds (1996-2003) using 50-m point counts and small mammals with removal trapping. Thinning and woody control alone had short-lived effects on avian communities, and the combination treatment increased avian parameters over the burn-only control in all years. Small mammal abundance showed similar trends as avian abundance for all three treatments when compared with the burn-only control, but only for 2 years post-treatment. Both avian and small mammal communities were temporarily enhanced by controlling woody vegetation with chemicals in addition to prescribed fire and thinning. Therefore, precommercial thinning in longleaf plantations, particularly when combined with woody control and prescribed fire, may benefit early-successional avian and small mammal communities by developing stand conditions more typical of natural longleaf stands maintained by periodic fire.

  18. Latency of the auditory evoked neuromagnetic field components: stimulus dependence and insights toward perception.

    Science.gov (United States)

    Roberts, T P; Ferrari, P; Stufflebeam, S M; Poeppel, D

    2000-03-01

    This review will focus on investigations of the auditory evoked neuromagnetic field component, the M100, detectable in the magnetoencephalogram recorded during presentation of auditory stimuli, approximately 100 milliseconds after stimulus onset. In particular, the dependence of M100 latency on attributes of the stimulus, such as intensity, pitch and timbre will be discussed, along with evidence relating M100 latency observations to perceptual features of the stimuli. Comparison with investigation of the analogous electrical potential component, the N1, will be made. Parametric development of stimuli from pure tones through complex tones to speech elements will be made, allowing the influence of spectral pitch, virtual pitch and perceptual categorization to be delineated and suggesting implications for the role of such latency observations in the study of speech processing. The final section will deal with potential clinical applications offered by M100 latency measurements, as objective indices of normal and abnormal cortical processing.

  19. Rein: Taming Tail Latency in Key-Value Stores via Multiget Scheduling

    KAUST Repository

    Reda, Waleed

    2017-04-17

    We tackle the problem of reducing tail latencies in distributed key-value stores, such as the popular Cassandra database.We focus on workloads of multiget requests, which batch together access to several data elements and parallelize read operations across the data store machines. We first analyze a production trace of a real system and quantify the skew due to multiget sizes, key popularity, and other factors. We then proceed to identify opportunities for reduction of tail latencies by recognizing the composition of aggregate requests and by carefully scheduling bottleneck operations that can otherwise create excessive queues. We design and implement a system called Rein, which reduces latency via inter-multiget scheduling using low overhead techniques. We extensively evaluate Rein via experiments in Amazon Web Services (AWS) and simulations. Our scheduling algorithms reduce the median, 95, and 99 percentile latencies by factors of 1.5, 1.5, and 1.9, respectively.

  20. Ocular herpes simplex virus: how are latency, reactivation, recurrent disease and therapy interrelated?

    Science.gov (United States)

    Al-Dujaili, Lena J; Clerkin, Patrick P; Clement, Christian; McFerrin, Harris E; Bhattacharjee, Partha S; Varnell, Emily D; Kaufman, Herbert E; Hill, James M

    2012-01-01

    Most humans are infected with herpes simplex virus (HSV) type 1 in early childhood and remain latently infected throughout life. While most individuals have mild or no symptoms, some will develop destructive HSV keratitis. Ocular infection with HSV-1 and its associated sequelae account for the majority of corneal blindness in industrialized nations. Neuronal latency in the peripheral ganglia is established when transcription of the viral genome is repressed (silenced) except for the latency-associated transcripts and microRNAs. The functions of latency-associated transcripts have been investigated since 1987. Roles have been suggested relating to reactivation, establishment of latency, neuronal protection, antiapoptosis, apoptosis, virulence and asymptomatic shedding. Here, we review HSV-1 latent infections, reactivation, recurrent disease and antiviral therapies for the ocular HSV diseases. PMID:21861620

  1. Reducing audio stimulus presentation latencies across studies, laboratories, and hardware and operating system configurations.

    Science.gov (United States)

    Babjack, Destiny L; Cernicky, Brandon; Sobotka, Andrew J; Basler, Lee; Struthers, Devon; Kisic, Richard; Barone, Kimberly; Zuccolotto, Anthony P

    2015-09-01

    Using differing computer platforms and audio output devices to deliver audio stimuli often introduces (1) substantial variability across labs and (2) variable time between the intended and actual sound delivery (the sound onset latency). Fast, accurate audio onset latencies are particularly important when audio stimuli need to be delivered precisely as part of studies that depend on accurate timing (e.g., electroencephalographic, event-related potential, or multimodal studies), or in multisite studies in which standardization and strict control over the computer platforms used is not feasible. This research describes the variability introduced by using differing configurations and introduces a novel approach to minimizing audio sound latency and variability. A stimulus presentation and latency assessment approach is presented using E-Prime and Chronos (a new multifunction, USB-based data presentation and collection device). The present approach reliably delivers audio stimuli with low latencies that vary by ≤1 ms, independent of hardware and Windows operating system (OS)/driver combinations. The Chronos audio subsystem adopts a buffering, aborting, querying, and remixing approach to the delivery of audio, to achieve a consistent 1-ms sound onset latency for single-sound delivery, and precise delivery of multiple sounds that achieves standard deviations of 1/10th of a millisecond without the use of advanced scripting. Chronos's sound onset latencies are small, reliable, and consistent across systems. Testing of standard audio delivery devices and configurations highlights the need for careful attention to consistency between labs, experiments, and multiple study sites in their hardware choices, OS selections, and adoption of audio delivery systems designed to sidestep the audio latency variability issue.

  2. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1997-12-01

    Studies on crisis stability, deterrence, and latency are presented in chronological order, which also reflects their logical order of development, captures the main features of stability analysis; relates first strike, crisis, and arms control stability as seen from US and Russian perspective; and addresses questions such as whether uncertainty in damage preference or defense deployment can be destabilizing. It illustrates the problems with alternative metrics, latency and reconstitution, and deep unilateral and proportional force reductions.

  3. Latency Estimation-Based Data Delivery Scheme for Vehicular Ad Hoc Networks

    OpenAIRE

    Gong, Haigang; Yu, Lingfei; Liu, Ke; Xu, Fulong; Wang, Xiaomin

    2012-01-01

    Data delivery is the most compelling issue for the applications in vehicular ad hoc networks. The characteristics of VAENTs such as highly dynamic topology and the road-constrained mobility pose great challenges for data delivery in vehicular ad hoc networks. In this paper, a latency estimation-based data delivery (LED) scheme is presented. According to the current location and the moving direction of the vehicles, LED calculates the expected delivery latency (EDL) of each vehicle and chooses...

  4. Identification of viral epitopes recognized by the immune system following vaccination and challenge with the H7N9 avian influenza virus from China

    Science.gov (United States)

    In March of 2013, the first cases of H7N9 influenza were reported in humans in China, and shortly thereafter the virus was confirmed from poultry in live bird markets. Since that time the virus has persisted in both human and avian populations. The genetic composition of these H7N9 influenza virus...

  5. Small-molecule screening using a human primary cell model of HIV latency identifies compounds that reverse latency without cellular activation

    Science.gov (United States)

    Yang, Hung-Chih; Xing, Sifei; Shan, Liang; O’Connell, Karen; Dinoso, Jason; Shen, Anding; Zhou, Yan; Shrum, Cynthia K.; Han, Yefei; Liu, Jun O.; Zhang, Hao; Margolick, Joseph B.; Siliciano, Robert F.

    2009-01-01

    The development of highly active antiretroviral therapy (HAART) to treat individuals infected with HIV-1 has dramatically improved patient outcomes, but HAART still fails to cure the infection. The latent viral reservoir in resting CD4+ T cells is a major barrier to virus eradication. Elimination of this reservoir requires reactivation of the latent virus. However, strategies for reactivating HIV-1 through nonspecific T cell activation have clinically unacceptable toxicities. We describe here the development of what we believe to be a novel in vitro model of HIV-1 latency that we used to search for compounds that can reverse latency. Human primary CD4+ T cells were transduced with the prosurvival molecule Bcl-2, and the resulting cells were shown to recapitulate the quiescent state of resting CD4+ T cells in vivo. Using this model system, we screened small-molecule libraries and identified a compound that reactivated latent HIV-1 without inducing global T cell activation, 5-hydroxynaphthalene-1,4-dione (5HN). Unlike previously described latency-reversing agents, 5HN activated latent HIV-1 through ROS and NF-κB without affecting nuclear factor of activated T cells (NFAT) and PKC, demonstrating that TCR pathways can be dissected and utilized to purge latent virus. Our study expands the number of classes of latency-reversing therapeutics and demonstrates the utility of this in vitro model for finding strategies to eradicate HIV-1 infection. PMID:19805909

  6. Validation of prospective portion size and latency to eat as measures of reactivity to snack foods.

    Science.gov (United States)

    van den Akker, Karolien; Bongers, Peggy; Hanssen, Imke; Jansen, Anita

    2017-09-01

    In experimental studies that investigate reactivity to the sight and smell of highly palatable snack foods, ad libitum food intake is commonly used as a behavioural outcome measure. However, this measure has several drawbacks. The current study investigated two intake-related measures not yet validated for food cue exposure research involving common snack foods: prospective portion size and latency to eat. We aimed to validate these measures by assessing prospective portion size and eating latencies in female undergraduate students who either underwent snack food exposure or a control exposure. Furthermore, we correlated prospective portion size and latency to eat with commonly used measures of food cue reactivity, i.e., self-reported desire to eat, salivation, and ad libitum food intake. Results showed increases in prospective portion size after food cue exposure but not after control exposure. Latency to eat did not differ between the two conditions. Prospective portion size correlated positively with desire to eat and food intake, and negatively with latency to eat. Latency to eat was also negatively correlated with desire to eat and food intake. It is concluded that the current study provides initial evidence for the prospective portion size task as a valid measure of reactivity to snack foods in a Dutch female and mostly healthy weight student population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Cellular and molecular mechanisms involved in the establishment of HIV-1 latency

    Directory of Open Access Journals (Sweden)

    Donahue Daniel A

    2013-02-01

    Full Text Available Abstract Latently infected cells represent the major barrier to either a sterilizing or a functional HIV-1 cure. Multiple approaches to reactivation and depletion of the latent reservoir have been attempted clinically, but full depletion of this compartment remains a long-term goal. Compared to the mechanisms involved in the maintenance of HIV-1 latency and the pathways leading to viral reactivation, less is known about the establishment of latent infection. This review focuses on how HIV-1 latency is established at the cellular and molecular levels. We first discuss how latent infection can be established following infection of an activated CD4 T-cell that undergoes a transition to a resting memory state and also how direct infection of a resting CD4 T-cell can lead to latency. Various animal, primary cell, and cell line models also provide insights into this process and are discussed with respect to the routes of infection that result in latency. A number of molecular mechanisms that are active at both transcriptional and post-transcriptional levels have been associated with HIV-1 latency. Many, but not all of these, help to drive the establishment of latent infection, and we review the evidence in favor of or against each mechanism specifically with regard to the establishment of latency. We also discuss the role of immediate silent integration of viral DNA versus silencing of initially active infections. Finally, we discuss potential approaches aimed at limiting the establishment of latent infection.

  8. Temporal processing and long-latency auditory evoked potential in stutterers

    Directory of Open Access Journals (Sweden)

    Raquel Prestes

    Full Text Available Abstract Introduction: Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. Objective: To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. Methods: The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n = 20 and non-stutters (n = 21, compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Results: Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Conclusion: Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components.

  9. Photosensor-Based Latency Measurement System for Head-Mounted Displays

    Directory of Open Access Journals (Sweden)

    Min-Woo Seo

    2017-05-01

    Full Text Available In this paper, a photosensor-based latency measurement system for head-mounted displays (HMDs is proposed. The motion-to-photon latency is the greatest reason for motion sickness and dizziness felt by users when wearing an HMD system. Therefore, a measurement system is required to accurately measure and analyze the latency to reduce these problems. The existing measurement system does not consider the actual physical movement in humans, and its accuracy is also very low. However, the proposed system considers the physical head movement and is highly accurate. Specifically, it consists of a head position model-based rotary platform, pixel luminance change detector, and signal analysis and calculation modules. Using these modules, the proposed system can exactly measure the latency, which is the time difference between the physical movement for a user and the luminance change of an output image. In the experiment using a commercial HMD, the latency was measured to be up to 47.05 ms. In addition, the measured latency increased up to 381.17 ms when increasing the rendering workload in the HMD.

  10. Impact of wave propagation delay on latency in optical communication systems

    Science.gov (United States)

    Kawanishi, Tetsuya; Kanno, Atsushi; Yoshida, Yuki; Kitayama, Ken-ichi

    2012-12-01

    Latency is an important figure to describe performance of transmission systems for particular applications, such as data transfer for earthquake early warning, transaction for financial businesses, interactive services such as online games, etc. Latency consists of delay due to signal processing at nodes and transmitters, and of signal propagation delay due to propagation of electromagnetic waves. The lower limit of the latency in transmission systems using conventional single mode fibers (SMFs) depends on wave propagation speed in the SMFs which is slower than c. Photonic crystal fibers, holly fibers and large core fibers can have low effective refractive indices, and can transfer light faster than in SMFs. In free-space optical systems, signals propagate with the speed c, so that the latency could be smaller than in optical fibers. For example, LEO satellites would transmit data faster than optical submarine cables, when the transmission distance is longer than a few thousand kilometers. This paper will discuss combination of various transmission media to reduce negative impact of the latency, as well as applications of low-latency systems.

  11. Comparison of middle latency responses in presbycusis patients with two different speech recognition scores.

    Science.gov (United States)

    Kirkim, Gunay; Madanoglu, Nevma; Akdas, Ferda; Serbetcioglu, M Bulent

    2007-12-01

    The purpose of this study is to evaluate whether the middle latency responses (MLR) can be used for an objective differentiation of patients with presbycusis having relatively good (Group I) and relatively poor speech recognition scores (Group II). All the participants of these groups had high frequency down-sloping hearing loss with an average of 26-60 dB HL. Data were collected from two described study groups and a control group, using pure tone audiometry, monosyllabic phonetically balanced word and synthetic sentence identification, as well as MLR. The study groups were compared with the control group. When patients in Group I were compared with the control group, only ipsilateral Na latency of middle latency evoked response was statistically significant in the right ear whereas ipsilateral Na latency in the right ear, ipsilateral and contralateral Na latency in the left ear of the patients in Group II were statistically significant. Thus, as an objective complementary tool for the evaluation of the speech perception ability of the patients with presbycusis, Na latency of MLR may be used in combination with the speech discrimination tests.

  12. Avian brains: Insights from development, behaviors and evolution.

    Science.gov (United States)

    Nomura, Tadashi; Izawa, Ei-Ichi

    2017-05-01

    Birds are an extensively specialized animal group with unique anatomical, physiological and ecological characteristics. Sophisticated social behaviors and remarkable cognitive abilities are present in several avian lineages, driven by their enlarged brains and intricate neural networks. These unique traits could be a result of adaptive evolution under the wide range of environmental constraints; however, the intrinsic mechanisms of avian brain development and evolution remain unclear. Here, we introduce recent findings regarding developmental aspects of avian brain organization and neuronal networks for specific avian behaviors, which provide an insight into the link between the evolution of brain development and complex cognitive functions. © 2017 Japanese Society of Developmental Biologists.

  13. Avian use of Norris Hill Wind Resource Area, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Harmata, A.; Podruzny, K.; Zelenak, J. [Montana State Univ., Bozeman, MT (United States). Biology Dept.

    1998-07-01

    This document presents results of a study of avian use and mortality in and near a proposed wind resource area in southwestern Montana. Data collected in autumn 1995 through summer 1996 represented preconstruction condition; it was compiled, analyzed, and presented in a format such that comparison with post-construction data would be possible. The primary emphasis of the study was recording avian migration in and near the wind resource area using state-of-the-art marine surveillance radar. Avian use and mortality were investigated during the breeding season by employing traditional avian sampling methods, radiotelemetry, radar, and direct visual observation. 61 figs., 34 tabs.

  14. Avian Circadian Organization: A Chorus of Clocks

    Science.gov (United States)

    Cassone, Vincent M

    2013-01-01

    In birds, biological clock function pervades all aspects of biology, controlling daily changes in sleep: wake, visual function, song, migratory patterns and orientation, as well as seasonal patterns of reproduction, song and migration. The molecular bases for circadian clocks are highly conserved, and it is likely the avian molecular mechanisms are similar to those expressed in mammals, including humans. The central pacemakers in the avian pineal gland, retinae and SCN dynamically interact to maintain stable phase relationships and then influence downstream rhythms through entrainment of peripheral oscillators in the brain controlling behavior and peripheral tissues. Birds represent an excellent model for the role played by biological clocks in human neurobiology; unlike most rodent models, they are diurnal, they exhibit cognitively complex social interactions, and their circadian clocks are more sensitive to the hormone melatonin than are those of nocturnal rodents. PMID:24157655

  15. INFECTION PECULIARITIES OF PLACENTA IN WOMEN WITH PREMATURE RUPTURE OF MEMBRANES AT 22 - 36 WEEKS DEPEND ON LATENCY

    Directory of Open Access Journals (Sweden)

    Наталья Николаевна Елизарова

    2017-05-01

    Results. With the increase in latency period, the incidence of infection of the placenta increased, including, placental chorioamnionitis, subchorial intervillusitis, membranitis, vascular-stromal funikulitis in comparison with women with less duration of latency period. When the latency period more than 7 days were statistically significantly more often recorded hyperplastic form and subcompensation degree of placental insufficiency (PI relative to women with less duration of latency period. The results of the microbiological study of the sequences did not depend on the duration of the latency period, but according to microbiological study, gram-positive flora is most often allocated: Staphylococcus epidermidis and Enterococcus faecalis.

  16. Procedure to measure real time latency using software defined radio in a W-band fiber-wireless link

    DEFF Research Database (Denmark)

    Rico-Martínez, Mónica; Morales, Alvaro; Mehmeri, Victor

    2017-01-01

    Reducing latency is a major challenge for current telecommunications systems. 5G networks are envisioned to achieve end-to-end latencies below 1 ms, thus enabling the Internet of Things (IoT) evolution and new applications such as Tactile Internet. In this article, we present a new procedure to m...... to measure real time latency in hybrid optical-wireless links. We obtained 2 ms end to end latency using Software Defined Radio to measure latency in a physical setup. We tested the procedure on W-band fiber-wireless link and validated the results against PING over GRE tunnel....

  17. Avian Radar - Is It Worth the Cost?

    Science.gov (United States)

    2012-06-01

    DC: The Federal Aviation Administration, in cooperation with the U.S. Department of Agriculture, Animal and Plant Health Inspection Service , Wildlife...Agriculture Animal and Plant Health Inspection Service Wildlife Services. York, D. L., Engeman, R. M., Cummings, J. L., Rossi, C. L., & Sinnett, D. R... Health Inspection Service , Wildlife Services. DOT/FAA/AR-09/61. (2010). Deployments of Avian Radars at Civil Airports. Springfield: National

  18. Common Avian Infection Plagued the Tyrant Dinosaurs

    Science.gov (United States)

    Wolff, Ewan D. S.; Salisbury, Steven W.; Horner, John R.; Varricchio, David J.

    2009-01-01

    Background Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name ‘Sue’) has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. Methodology/Principal Findings We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. Conclusions/Significance This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation. PMID:19789646

  19. Common avian infection plagued the tyrant dinosaurs.

    Directory of Open Access Journals (Sweden)

    Ewan D S Wolff

    Full Text Available BACKGROUND: Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue' has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. METHODOLOGY/PRINCIPAL FINDINGS: We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. CONCLUSIONS/SIGNIFICANCE: This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation.

  20. Avian influenza in birds and mammals.

    Science.gov (United States)

    Cardona, Carol J; Xing, Zheng; Sandrock, Christian E; Davis, Cristina E

    2009-07-01

    The disease syndromes caused by avian influenza viruses are highly variable depending on the host species infected, its susceptibility and response to infection and the virulence of the infecting viral strain. Although avian influenza viruses have a broad host range in general, it is rare for an individual strain or subtype to infect more than one species. The H5N1 highly pathogenic avian influenza virus (HPAIV) lineages of viruses that descended from A/goose/Guandong/96 (H5N1 HPAIV) are unusual in the diversity of species they have infected worldwide. Although the species affected by H5N1 HPAI in the field and those that have been experimentally studied are diverse, their associated disease syndromes are remarkably similar across species. In some species, multi-organ failure and death are rapid and no signs of the disease are observed. Most prominently in this category are chickens and other avian species of the order Galliformes. In other species, neurologic signs develop resulting in the death of the host. This is what has been reported in domestic cats (Carnivora), geese (Anseriformes), ratites (Struthioniformes), pigeons inoculated with high doses (Columbiformes) and ducks infected with H5N1 HPAIV isolated since 2002 (Anseriformes). In some other species, the disease is more prolonged and although multi-organ failure and death are the eventual outcomes, the signs of disease are more extensive. Predominantly, these species include humans (Primates) and the laboratory models of human disease, the ferret (Carnivora), mouse (Rodentia) and cynamologous macaques (Primates). Finally, some species are more resistant to infection with H5N1 HPAIV and show few or no signs of disease. These species include pigeons in some studies (Columbiformes), ducks inoculated with pre-2002 isolates (Anseriformes), and pigs (Artiodactyla).

  1. Common avian infection plagued the tyrant dinosaurs.

    Science.gov (United States)

    Wolff, Ewan D S; Salisbury, Steven W; Horner, John R; Varricchio, David J

    2009-09-30

    Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue') has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation.

  2. The Avian Transcriptome Response to Malaria Infection

    OpenAIRE

    Videvall, Elin; Cornwallis, Charlie K.; Palinauskas, Vaidas; Valki?nas, Gediminas; Hellgren, Olof

    2015-01-01

    Malaria parasites are highly virulent pathogens which infect a wide range of vertebrates. Despite their importance, the way different hosts control and suppress malaria infections remains poorly understood. With recent developments in next-generation sequencing techniques, however, it is now possible to quantify the response of the entire transcriptome to infections. We experimentally infected Eurasian siskins (Carduelis spinus) with avian malaria parasites (Plasmodium ashfordi), and used hig...

  3. Integration and Validation of Avian Radars (IVAR)

    Science.gov (United States)

    2011-07-01

    shape, density, gender ) is problematic; • Not suited to high-clutter environments (e.g., in forests, near buildings); • Health & safety issues...Fuca and the Saratoga Passage and within the rain shadow of the Olympic Mountains, NAS Whidbey Island offers high quality year round training...was to demonstrate that the digital avian radars being evaluated by the IVAR project can automatically discriminate the echoes of moving targets

  4. Applications of thermal imaging in avian science

    OpenAIRE

    McCafferty, D.J.

    2013-01-01

    Thermal imaging, or infrared thermography, has been used in avian science since the 1960s. More than 30 species of birds, ranging in size from passerines to ratites, have been studied using this technology. The main strength of this technique is that it is a non-invasive and non-contact method of measuring surface temperature. Its limitations and measurement errors are well understood and suitable protocols have been developed for a variety of experimental settings. Thermal imaging has been u...

  5. Tracing the evolution of avian wing digits.

    Science.gov (United States)

    Xu, Xing; Mackem, Susan

    2013-06-17

    It is widely accepted that birds are a subgroup of dinosaurs, but there is an apparent conflict: modern birds have been thought to possess only the middle three fingers (digits II-III-IV) of an idealized five-digit tetrapod hand based on embryological data, but their Mesozoic tetanuran dinosaur ancestors are considered to have the first three digits (I-II-III) based on fossil evidence. How could such an evolutionary quirk arise? Various hypotheses have been proposed to resolve this paradox. Adding to the confusion, some recent developmental studies support a I-II-III designation for avian wing digits whereas some recent paleontological data are consistent with a II-III-IV identification of the Mesozoic tetanuran digits. A comprehensive analysis of both paleontological and developmental data suggests that the evolution of the avian wing digits may have been driven by homeotic transformations of digit identity, which are more likely to have occurred in a partial and piecemeal manner. Additionally, recent genetic studies in mouse models showing plausible mechanisms for central digit loss invite consideration of new alternative possibilities (I-II-IV or I-III-IV) for the homologies of avian wing digits. While much progress has been made, some advances point to the complexity of the problem and a final resolution to this ongoing debate demands additional work from both paleontological and developmental perspectives, which will surely yield new insights on mechanisms of evolutionary adaptation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Avian cytokines in health and disease

    Directory of Open Access Journals (Sweden)

    Wigley P

    2003-01-01

    Full Text Available Cytokines are proteins secreted by cells that play an important role in the activation and regulation of other cells and tissues during inflammation and immune responses. Although well described in several mammalian species, the role of cytokines and other related proteins is poorly understood in avian species. Recent advances in avian genetics and immunology have begun to allow the exploration of cytokines in health and disease. Cytokines may be classified in a number of ways, but may be conveniently arranged into four broad groups on the basis of their function. Proinflammatory cytokines such as interleukin-6 and interleukin-1beta play a role in mediating inflammation during disease or injury. Th1 cytokines, including interleukin-12 and interferon-gamma, are involved in the induction of cell-mediated immunity, whereas Th2 cytokines such as interleukin-4 are involved in the induction of humoral immunity. The final group Th3 or Tr cytokines play a role in regulation of immunity. The role of various cytokines in infectious and non-infectious diseases of chickens and turkeys is now being investigated. Although there are only a few reliable ELISAs or bioassays developed for avian cytokines, the use of molecular techniques, and in particular quantitative RT-PCR (Taqman has allowed investigation of cytokine responses in a number of diseases including salmonellosis, coccidiosis and autoimmune thyroiditis. In addition the use of recombinant cytokines as therapeutic agents or as vaccine adjuvants is now being explored.

  7. Global phylogeographic limits of Hawaii's avian malaria

    Science.gov (United States)

    Beadell, J.S.; Ishtiaq, F.; Covas, R.; Melo, M.; Warren, B.H.; Atkinson, C.T.; Bensch, S.; Graves, G.R.; Jhala, Y.V.; Peirce, M.A.; Rahmani, A.R.; Fonseca, D.M.; Fleischer, R.C.

    2006-01-01

    The introduction of avian malaria (Plasmodium relictum) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite within a global ecological and evolutionary context. Using fragments of the parasite mitochondrial gene cytochrome b and the nuclear gene dihydrofolate reductase-thymidylate synthase obtained from a global survey of greater than 13 000 avian samples, we show that Hawaii's avian malaria, which can cause high mortality and is a major limiting factor for many species of native passerines, represents just one of the numerous lineages composing the morphological parasite species. The single parasite lineage detected in Hawaii exhibits a broad host distribution worldwide and is dominant on several other remote oceanic islands, including Bermuda and Moorea, French Polynesia. The rarity of this lineage in the continental New World and the restriction of closely related lineages to the Old World suggest limitations to the transmission of reproductively isolated parasite groups within the morphological species. ?? 2006 The Royal Society.

  8. Short stature

    Science.gov (United States)

    ... as her parents. Providers call this "constitutional growth delay." If one or both parents are short, your ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  9. SHORT COMMUNICATION

    African Journals Online (AJOL)

    PROF P.T. KAYE

    . SHORT COMMUNICATION. Formation and Structural Analysis of Novel Dibornyl Ethers. Perry T. Kaye*, Andrew R. Duggan, Joseph M. Matjila, Warner E. Molema, and. Swarnam S. Ravindran. Department of Chemistry, Rhodes University, Grahamstown, ...

  10. A method to preserve low parasitaemia Plasmodium-infected avian blood for host and vector infectivity assays.

    Science.gov (United States)

    Carlson, Jenny S; Giannitti, Federico; Valkiūnas, Gediminas; Tell, Lisa A; Snipes, Joy; Wright, Stan; Cornel, Anthony J

    2016-03-11

    Avian malaria vector competence studies are needed to understand more succinctly complex avian parasite-vector-relations. The lack of vector competence trials may be attributed to the difficulty of obtaining gametocytes for the majority of Plasmodium species and lineages. To conduct avian malaria infectivity assays for those Plasmodium spp. and lineages that are refractory to in vitro cultivation, it is necessary to obtain and preserve for short periods sufficient viable merozoites to infect naïve donor birds to be used as gametocyte donors to infect mosquitoes. Currently, there is only one described method for long-term storage of Plasmodium spp.-infected wild avian blood and it is reliable at a parasitaemia of at least 1%. However, most naturally infected wild-caught birds have a parasitaemia of much less that 1%. To address this problem, a method for short-term storage of infected wild avian blood with low parasitaemia (even ≤ 0.0005%) has been explored and validated. To obtain viable infective merozoites, blood was collected from wild birds using a syringe containing the anticoagulant and the red blood cell preservative citrate phosphate dextrose adenine solution (CPDA). Each blood sample was stored at 4 °C for up to 48 h providing sufficient time to determine the species and parasitaemia of Plasmodium spp. in the blood by morphological examination before injecting into donor canaries. Plasmodium spp.--infected blood was inoculated intravenously into canaries and once infection was established, Culex stigmatosoma, Cx. pipiens and Cx. quinquefasciatus mosquitoes were then allowed to feed on the infected canaries to validate the efficacy of this method for mosquito vector competence assays. Storage of Plasmodium spp.--infected donor blood at 4 °C yielded viable parasites for 48 h. All five experimentally-infected canaries developed clinical signs and were infectious. Pathologic examination of three canaries that later died revealed splenic lesions typical of

  11. Characterisation and Identification of Avian Influenza Virus (AI

    Directory of Open Access Journals (Sweden)

    Dyah Ayu Hewajuli

    2008-06-01

    Full Text Available Avian Influenza is caused by Influenza A virus which is a member of Orthomyxoviridae family. Influenza A virus is enveloped single stranded RNA with eight-segmented, negative polarity and filament or oval form, 50 – 120 by 200 – 300 nm diameters. Influenza A viruses have been found to infect birds, human, pig, horse and sometimes in the other mammalian such as seal and whale. The viruses are divided into different subtypes based on the antigenic protein which covers the virus surface i.e. Haemaglutinin (HA and Neuraminidase (NA. In addition, the nomenclature of subtype virus is based on HA and NA i.e HxNx, for example H5N1, H9N2 and the others. According to pathogenic, it could be divided into two distinct groups, they are Highly Pathogenic Avian Influenza (HPAI and Low Pathogenic Avian Influenza (LPAI. The Avian Influenza viruses have been continuously occurred and spread out in some continents such us America, Europe, Africa and Asian countries. The outbreak of Avian Influenza caused high mortality on birds and it has been reported that in human case Avian Influenza subtype H5N1 virus has caused several deaths. To anticipate this condition, an effort to prevent the transmission of Avian Influenza is needed. These strategic attempts include biosecurity, depopulation, vaccination, control of virus movement, monitoring and evaluation. Laboratory diagnostic plays an important role for successful prevention, control and eradication programs of Avian Influenza. Recently, there are two diagnostic methods for Avian Influenza. They are conventional (virological diagnosis and molecular methods. The conventional method is usually used for initial diagnostic of Avian Influenza. The conventional method takes more time and more costly, whereas the molecular method is more effective than conventional method. Based on the available diagnostic technique, basically diagnostic of Avian Influenza is done by serology test, isolation and identification as well

  12. Trade-off between synergy and efficacy in combinations of HIV-1 latency-reversing agents.

    Science.gov (United States)

    Gupta, Vipul; Dixit, Narendra M

    2018-02-01

    Eradicating HIV-1 infection is difficult because of the reservoir of latently infected cells that gets established soon after infection, remains hidden from antiretroviral drugs and host immune responses, and retains the capacity to reignite infection following the cessation of treatment. Drugs called latency-reversing agents (LRAs) are being developed to reactivate latently infected cells and render them susceptible to viral cytopathicity or immune killing. Whereas individual LRAs have failed to induce adequate reactivation, pairs of LRAs have been identified recently that act synergistically and hugely increase reactivation levels compared to individual LRAs. The maximum synergy achievable with LRA pairs is of clinical importance, as it would allow latency-reversal with minimal drug exposure. Here, we employed stochastic simulations of HIV-1 transcription and translation in latently infected cells to estimate this maximum synergy. We incorporated the predominant mechanisms of action of the two most promising classes of LRAs, namely, protein kinase C agonists and histone deacetylase inhibitors, and quantified the activity of individual LRAs in the two classes by mapping our simulations to corresponding in vitro experiments. Without any adjustable parameters, our simulations then quantitatively captured experimental observations of latency-reversal when the LRAs were used in pairs. Performing simulations representing a wide range of drug concentrations, we estimated the maximum synergy achievable with these LRA pairs. Importantly, we found with all the LRA pairs we considered that concentrations yielding the maximum synergy did not yield the maximum latency-reversal. Increasing concentrations to increase latency-reversal compromised synergy, unravelling a trade-off between synergy and efficacy in LRA combinations. The maximum synergy realizable with LRA pairs would thus be restricted by the desired level of latency-reversal, a constrained optimum we elucidated with

  13. HIV Reactivation from Latency after Treatment Interruption Occurs on Average Every 5-8 Days--Implications for HIV Remission.

    Directory of Open Access Journals (Sweden)

    Mykola Pinkevych

    2015-07-01

    Full Text Available HIV infection can be effectively controlled by anti-retroviral therapy (ART in most patients. However therapy must be continued for life, because interruption of ART leads to rapid recrudescence of infection from long-lived latently infected cells. A number of approaches are currently being developed to 'purge' the reservoir of latently infected cells in order to either eliminate infection completely, or significantly delay the time to viral recrudescence after therapy interruption. A fundamental question in HIV research is how frequently the virus reactivates from latency, and thus how much the reservoir might need to be reduced to produce a prolonged antiretroviral-free HIV remission. Here we provide the first direct estimates of the frequency of viral recrudescence after ART interruption, combining data from four independent cohorts of patients undergoing treatment interruption, comprising 100 patients in total. We estimate that viral replication is initiated on average once every ≈6 days (range 5.1- 7.6 days. This rate is around 24 times lower than previous thought, and is very similar across the cohorts. In addition, we analyse data on the ratios of different 'reactivation founder' viruses in a separate cohort of patients undergoing ART-interruption, and estimate the frequency of successful reactivation to be once every 3.6 days. This suggests that a reduction in the reservoir size of around 50-70-fold would be required to increase the average time-to-recrudescence to about one year, and thus achieve at least a short period of anti-retroviral free HIV remission. Our analyses suggests that time-to-recrudescence studies will need to be large in order to detect modest changes in the reservoir, and that macaque models of SIV latency may have much higher frequencies of viral recrudescence after ART interruption than seen in human HIV infection. Understanding the mean frequency of recrudescence from latency is an important first step in

  14. HIV Reactivation from Latency after Treatment Interruption Occurs on Average Every 5-8 Days—Implications for HIV Remission

    Science.gov (United States)

    Pinkevych, Mykola; Cromer, Deborah; Tolstrup, Martin; Grimm, Andrew J.; Cooper, David A.; Lewin, Sharon R.; Søgaard, Ole S.; Rasmussen, Thomas A.; Kent, Stephen J.; Kelleher, Anthony D.; Davenport, Miles P.

    2015-01-01

    HIV infection can be effectively controlled by anti-retroviral therapy (ART) in most patients. However therapy must be continued for life, because interruption of ART leads to rapid recrudescence of infection from long-lived latently infected cells. A number of approaches are currently being developed to ‘purge’ the reservoir of latently infected cells in order to either eliminate infection completely, or significantly delay the time to viral recrudescence after therapy interruption. A fundamental question in HIV research is how frequently the virus reactivates from latency, and thus how much the reservoir might need to be reduced to produce a prolonged antiretroviral-free HIV remission. Here we provide the first direct estimates of the frequency of viral recrudescence after ART interruption, combining data from four independent cohorts of patients undergoing treatment interruption, comprising 100 patients in total. We estimate that viral replication is initiated on average once every ≈6 days (range 5.1- 7.6 days). This rate is around 24 times lower than previous thought, and is very similar across the cohorts. In addition, we analyse data on the ratios of different ‘reactivation founder’ viruses in a separate cohort of patients undergoing ART-interruption, and estimate the frequency of successful reactivation to be once every 3.6 days. This suggests that a reduction in the reservoir size of around 50-70-fold would be required to increase the average time-to-recrudescence to about one year, and thus achieve at least a short period of anti-retroviral free HIV remission. Our analyses suggests that time-to-recrudescence studies will need to be large in order to detect modest changes in the reservoir, and that macaque models of SIV latency may have much higher frequencies of viral recrudescence after ART interruption than seen in human HIV infection. Understanding the mean frequency of recrudescence from latency is an important first step in approaches to

  15. 2 original article non-attenuation of highly pathogenic avian ...

    African Journals Online (AJOL)

    Dr Oboro VO

    Ularamu, H. G1., Ponman, S1 and Nwagbo, I2., 1 FAO Regional Laboratory for Avian Influenza and Newcastle. Disease (West and Central ... Avian influenza H5N1 represents one of the most researched viruses in laboratories world-wide in recent times with regards ..... Cayouette B. Kinetics of ultra- violet light inactivation of.

  16. High prevalence of avian malaria infection to avifauna at Cape ...

    African Journals Online (AJOL)

    This investigation was undertaken during January and February 2004, to determine the epidemiological risk of avian malaria infection to seabirds at the proposed marine animal rehabilitation complex, to be sited at Cape Receife. Despite low numbers of mosquitoes trapped, the incidence of avian malaria infections was ...

  17. Genetic differences between avian and human isolates of Candida dubliniensis.

    LENUS (Irish Health Repository)

    McManus, Brenda A

    2009-09-01

    When Candida dubliniensis isolates obtained from seabird excrement and from humans in Ireland were compared by using multilocus sequence typing, 13 of 14 avian isolates were genetically distinct from human isolates. The remaining avian isolate was indistinguishable from a human isolate, suggesting that transmission may occur between humans and birds.

  18. Avian fossils from the Early Miocene Moghra Formation of Egypt ...

    African Journals Online (AJOL)

    Avian remains from the Early Miocene (~17 Ma) Moghra Formation of Egypt include new records of 'waterbirds' (storks, herons, pelicans and allies) and a ratite. Only a single avian fossil has been previously reported from Wadi Moghra and, thus, additional knowledge of the avifauna complements previously documented ...

  19. Avian influenza, Newcastle and Gumboro disease antibodies and ...

    African Journals Online (AJOL)

    Studies on avian influenza and Newcastle disease focus on waterfowls, considered natural reservoirs of these viruses. This study surveyed avian influenza (AI), Gumboro and Newcastle disease antibodies and antigens in birds in live wild bird markets (LWBMs), live poultry markets (LPMs) and free flying in Kaduna State ...

  20. Flock-based surveillance for lowpathogenic avian influenza virus in ...

    African Journals Online (AJOL)

    Flock-based surveillance for lowpathogenic avian influenza virus in commercial breeders and layers, southwest Nigeria. ... African Journal of Infectious Diseases ... Background: Flock surveillance systems for avian influenza (AI) virus play a critical role in countries where vaccination is not practiced so as to establish the ...

  1. Avian nestling predation by endangered Mount Graham red squirrel

    Science.gov (United States)

    Claire A. Zugmeyer; John L. Koprowski

    2007-01-01

    Studies using artificial nests or remote cameras have documented avian predation by red squirrels (Tamiasciurus hudsonicus). Although several direct observations of avian predation events are known in the northern range of the red squirrel distribution, no accounts have been reported in the southern portion. We observed predation upon a hermit thrush...

  2. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ..., Killed Virus. 113.208 Section 113.208 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian Encephalomyelitis Vaccine, Killed Virus. Avian...

  3. Prevention and Treatment of Avian Influenza A Viruses in People

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  4. Avian Influenza A (H7N9) Virus

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  5. Avian research in the U.S. Forest Service

    Science.gov (United States)

    Beatrice Van Horne

    2005-01-01

    Avian research in the Federal Government is in a crisis. Yes, there is a strong interest in avian research, as evidenced by the size and level of interest in this conference. But political parties increasingly see wildlife research as expendable. At the same time, the reaction to environment-friendly legislation of the 1970s and 1980s has been strong from both sides....

  6. Molecular cloning and functional characterization of avian interleukin-19

    Science.gov (United States)

    The present study describes the cloning and functional characterization of avian interleukin (IL)-19, a cytokine that, in mammals, alters the balance of Th1 and Th2 cells in favor of the Th2 phenotype. The full-length avian IL-19 gene, located on chromosome 26, was amplified from LPS-stimulated chi...

  7. Socioeconomic Impacts of Avian Influenza on Small and Backyard ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    and compensation schemes are more difficult to enforce than in large commercial poultry farms. Moreover, small and backyard farmers have fewer reserves to cope with the financial impact of avian influenza and, possibly, greater motivation to circumvent government control measures. The Asian Partnership for Avian ...

  8. Ontogeny of avian thermoregulation from a neural point of view

    NARCIS (Netherlands)

    Baarendse, P.J.J.; Debonne, M.; Decuypere, M.P.; Kemp, B.; Brand, van den H.

    2007-01-01

    The ontogeny of thermoregulation differs among (avian) species, but in all species both neural and endocrinological processes are involved. In this review the neural processes in ontogeny of thermoregulation during the prenatal and early postnatal phase are discussed. Only in a few avian species

  9. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Science.gov (United States)

    2010-01-01

    ... Isolate. 113.70 Section 113.70 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or modified...

  10. Detection of avian nephritis virus and chicken astrovirus in Nigerian ...

    African Journals Online (AJOL)

    Avian nephritis virus (ANV) and chicken astrovirus (CAstV) are widely distributed in poultry flocks worldwide, causing growth retardation. However, these avian astroviruses have not been previously diagnosed in poultry species in Nigeria. Real-time reverse transcriptase-polymerase chain reaction (rRTPCR) and reverse ...

  11. Nanostructures for the development of vaccines against avian ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2018-01-12

    Jan 12, 2018 ... Photo: IDRC / Sven Torfinn. The impact of avian influenza. The livelihoods of smallholder farmers, who most frequently own poultry have been severely impacted by recent outbreaks of avian influenza (AI). The severity of the disease can range from mild to extremely severe cases with up to a 100% mortality ...

  12. Compound motor action potential duration and latency are markers of recurrent laryngeal nerve injury.

    Science.gov (United States)

    Bhatt, Neel K; Park, Andrea M; Al-Lozi, Mohammad T; Gale, Derrick C; Paniello, Randal C

    2017-08-01

    Compound motor action potential (CMAP) can quantitatively evaluate innervation following injury to the recurrent laryngeal nerve (RLN) in canines. CMAP duration (the total time of CMAP) and latency (the time between the nerve impulse and the onset of action potentials) have not been assessed following RLN injury. Animal study. Twelve canine hemilaryngeal preparations were investigated. Baseline CMAP duration and latency were derived. Group A (n = 5) underwent RLN stretch injury, and group B (n = 7) underwent RLN transection/repair. The change in CMAP duration and latency was assessed between the baseline and 6-month measurements using receiver operator characteristic (ROC) curves for each group individually and combined. Six months following injury, transection/repair injuries had the most significant increase in CMAP duration (2.8 ± 0.6 ms vs. 4.2 ± 0.8 ms, difference 1.4 ms 95% confidence interval [CI]: 0.43 to 2.40) and latency (2.6 ± 0.5 ms vs. 5.6 ± 1.5 ms, difference 3.0 ms 95% CI: 1.65 to 4.38). Stretch injuries also caused an increase in CMAP duration (2.3 ± 0.8 ms vs. 3.0 ± 0.6 ms, difference 0.7 ms 95% CI: -0.49 to 1.77) and latency (2.5 ± 0.8 ms vs. 4.7 ± 1.5 ms, difference 2.3 95% CI: 0.76 to 3.80). Using ROC curves, CMAP duration and latency differentiated between the baseline control and RLN injury at 6 months (area under the curve = 0.78 and 0.98, respectively). CMAP duration and latency are both quantitative measures that may have clinical utility as markers of RLN injury. CMAP latency had superior discrimination between injured and uninjured RLNs. Increased CMAP duration and latency may be explained by incomplete myelination and focal conduction block. NA. Laryngoscope, 127:1855-1860, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  13. Transvaginal cervical length and amniotic fluid index: can it predict delivery latency following preterm premature rupture of membranes?

    Science.gov (United States)

    Mehra, Suwan; Amon, Erol; Hopkins, Sarah; Gavard, Jeffrey A; Shyken, Jaye

    2015-03-01

    We sought to determine whether transvaginal cervical length (TVCL), amniotic fluid index (AFI), or a combination of both can predict delivery latency within 7 days in women presenting with preterm premature rupture of membranes (PPROM). This was a prospective observational study of TVCL measurements in 106 singleton pregnancies with PPROM between 23-33 weeks. Delivery latency was defined as the period (in days) from the initial TVCL after PPROM to delivery of the infant, with our primary outcome being delivery within 7 days of TVCL. The independent predictability of significant characteristics for delivery within 7 days was determined using multiple logistic regression. Sensitivity, specificity, and predictive values were used to examine whether the presence of a short TVCL, AFI, or a combination of both affected the risk of delivery within 7 days. Delivery within 7 days occurred in 51/106 (48%) of pregnancies. Median duration (interquartile range) from PPROM to delivery and TVCL to delivery was 8 days (4.0-16.0) and 8 days (3.0-15.0), respectively. Using multiple regression TVCL as a continuous variable (odds ratio, 0.65; 95% confidence interval, 0.44-0.97; P 7 days for TVCL >2 cm alone was 61%. This predictive value changed when analyzed in conjunction with an AFI ≤5 cm and >5 cm at 42% and 89%, respectively. A shorter TVCL and an AFI ≤5 cm independently predict delivery within 7 days in women presenting with PPROM. The combination of an AFI >5 cm and TVCL >2 cm greatly improved the potential to remain undelivered at 7 days following cervical length assessment. These findings may be helpful for counseling and optimizing maternal and neonatal care in women with PPROM. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    Science.gov (United States)

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  15. The utility of a 5(th) nap in multiple sleep latency test.

    Science.gov (United States)

    Muza, Rexford; Lykouras, Dimosthenis; Rees, Kate

    2016-02-01

    This is the first study that aimed to look specifically at the utility of the 5(th) nap in the multiple sleep latency test (MSLT), a test used to assist in the diagnosis of narcolepsy. Data was retrospectively collected from the Sleep Disorders Centre of a Tertiary Hospital on patients that had a 5(th) nap during their MSLT from the 08(th) November 2011 to 12(th) November 2014. Fifty-three patients had a 5(th) nap performed out of 378 MSLT studies. In 16% of cases a diagnosis of narcolepsy was given directly due to the inclusion of the 5(th) nap on the MSLT. Here a 5(th) nap allowed diagnostic criteria of mean sleep latency 2 SOREMPS to be met. In 53% of cases the mean sleep latency increased due to 5(th) nap inclusion; the mean sleep latency of the first four naps was 5.6 vs. 6.7 after inclusion of the 5(th) nap. The 5(th) nap is not often performed within the MSLT studies. Our study shows that only a few patients may benefit from a 5(th) nap opportunity which also led to increase of the mean sleep latency at the expense of extra time, cost, labour and increased patient anxiety.

  16. Dynamics of HIV latency and reactivation in a primary CD4+ T cell model.

    Directory of Open Access Journals (Sweden)

    Pejman Mohammadi

    2014-05-01

    Full Text Available HIV latency is a major obstacle to curing infection. Current strategies to eradicate HIV aim at increasing transcription of the latent provirus. In the present study we observed that latently infected CD4+ T cells from HIV-infected individuals failed to produce viral particles upon ex vivo exposure to SAHA (vorinostat, despite effective inhibition of histone deacetylases. To identify steps that were not susceptible to the action of SAHA or other latency reverting agents, we used a primary CD4+ T cell model, joint host and viral RNA sequencing, and a viral-encoded reporter. This model served to investigate the characteristics of latently infected cells, the dynamics of HIV latency, and the process of reactivation induced by various stimuli. During latency, we observed persistence of viral transcripts but only limited viral translation. Similarly, the reactivating agents SAHA and disulfiram successfully increased viral transcription, but failed to effectively enhance viral translation, mirroring the ex vivo data. This study highlights the importance of post-transcriptional blocks as one mechanism leading to HIV latency that needs to be relieved in order to purge the viral reservoir.

  17. LATENCY DELAY OF THE VASTUS MEDIALIS OBLIQUE AND VASTUS LATERALIS IN INDIVIDUALS WITH PATELLOFEMORAL PAIN SYNDROME

    Directory of Open Access Journals (Sweden)

    Eduardo Enrique Guzmán Muñoz

    2016-11-01

    Full Text Available Purpose: To determine the onset latency of the vastus medialis oblique (VMO and vastus lateralis (VL muscles in individuals with patellofemoral pain syndrome (PFPS. Methodology: A case-control study. Fourteen female participants with PFPS and fifteen female participants without PFPS performed a sudden lower extremity perturbation test in anterior and posterior directions. The electromyographic onset latency of the VMO and VL were measured during this test. A student’s t-test was used to compare muscle latency between the groups. Significance level was established a priori at P < 0.05. Results: During sudden anterior perturbation a significant latency delay of the VMO (p < 0.001 and VL muscles (p = 0.019 was observed in participants with PFPS. In the sudden posterior perturbation a delayed response in the activation of VMO (p = 0.023 and VL (p < 0.038 muscles was observed in individuals with PFPS. Conclusions: The results of this study indicate that individuals with PFPS have a motor deficit reflected in the latency delay of VMO and VL muscles during a sudden perturbation in the sagittal plane.

  18. Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins.

    Science.gov (United States)

    Khan, Sheraz; Iqbal, Mazhar; Tariq, Muhammad; Baig, Shahid M; Abbas, Wasim

    2018-01-01

    HIV-1 latency allows the virus to persist until reactivation, in a transcriptionally silent form in its cellular reservoirs despite the presence of effective cART. Such viral persistence represents a major barrier to HIV eradication since treatment interruption leads to rebound plasma viremia. Polycomb group (PcG) proteins have recently got a considerable attention in regulating HIV-1 post-integration latency as they are involved in the repression of proviral gene expression through the methylation of histones. This epigenetic regulation plays an important role in the establishment and maintenance of HIV-1 latency. In fact, PcG proteins act in complexes and modulate the epigenetic signatures of integrated HIV-1 promoter. Key role played by PcG proteins in the molecular control of HIV-1 latency has led to hypothesize that PcG proteins may represent a valuable target for future HIV-1 therapy in purging HIV-1 reservoirs. In this regard, various small molecules have been synthesized or explored to specifically block the epigenetic activity of PcG. In this review, we will highlight the possible therapeutic approaches to achieve either a functional or sterilizing cure of HIV-1 infection with special focus on histone methylation by PcG proteins together with current and novel pharmacological approaches to reactivate HIV-1 from latency that could ultimately lead towards a better clearance of viral latent reservoirs.

  19. Molecular control of HIV-1 postintegration latency: implications for the development of new therapeutic strategies

    Directory of Open Access Journals (Sweden)

    Van Lint Carine

    2009-12-01

    Full Text Available Abstract The persistence of HIV-1 latent reservoirs represents a major barrier to virus eradication in infected patients under HAART since interruption of the treatment inevitably leads to a rebound of plasma viremia. Latency establishes early after infection notably (but not only in resting memory CD4+ T cells and involves numerous host and viral trans-acting proteins, as well as processes such as transcriptional interference, RNA silencing, epigenetic modifications and chromatin organization. In order to eliminate latent reservoirs, new strategies are envisaged and consist of reactivating HIV-1 transcription in latently-infected cells, while maintaining HAART in order to prevent de novo infection. The difficulty lies in the fact that a single residual latently-infected cell can in theory rekindle the infection. Here, we review our current understanding of the molecular mechanisms involved in the establishment and maintenance of HIV-1 latency and in the transcriptional reactivation from latency. We highlight the potential of new therapeutic strategies based on this understanding of latency. Combinations of various compounds used simultaneously allow for the targeting of transcriptional repression at multiple levels and can facilitate the escape from latency and the clearance of viral reservoirs. We describe the current advantages and limitations of immune T-cell activators, inducers of the NF-κB signaling pathway, and inhibitors of deacetylases and histone- and DNA- methyltransferases, used alone or in combinations. While a solution will not be achieved by tomorrow, the battle against HIV-1 latent reservoirs is well- underway.

  20. ScriptingRT: A Software Library for Collecting Response Latencies in Online Studies of Cognition.

    Directory of Open Access Journals (Sweden)

    Thomas W Schubert

    Full Text Available ScriptingRT is a new open source tool to collect response latencies in online studies of human cognition. ScriptingRT studies run as Flash applets in enabled browsers. ScriptingRT provides the building blocks of response latency studies, which are then combined with generic Apache Flex programming. Six studies evaluate the performance of ScriptingRT empirically. Studies 1-3 use specialized hardware to measure variance of response time measurement and stimulus presentation timing. Studies 4-6 implement a Stroop paradigm and run it both online and in the laboratory, comparing ScriptingRT to other response latency software. Altogether, the studies show that Flash programs developed in ScriptingRT show a small lag and an increased variance in response latencies. However, this did not significantly influence measured effects: The Stroop effect was reliably replicated in all studies, and the found effects did not depend on the software used. We conclude that ScriptingRT can be used to test response latency effects online.

  1. Cytomegalovirus latency and reactivation: Recent insights into an age old problem

    Science.gov (United States)

    Dupont, L.; Reeves, M.B.

    2017-01-01

    Summary Human cytomegalovirus (HCMV) infection remains a major cause of morbidity in patient populations. In certain clinical settings it is the reactivation of the pre-existing latent infection in the host that poses the health risk. The prevailing view of HCMV latency was that the virus was essentially quiescent in myeloid progenitor cells and that terminal differentiation resulted in the initiation of the lytic lifecycle and reactivation of infectious virus. However, our understanding of HCMV latency and reactivation at the molecular level has been greatly enhanced through recent advancements in systems biology approaches to perform global analyses of both experimental and natural latency. These approaches, in concert with more classical reductionist experimentation, are furnishing researchers with new concepts in cytomegalovirus latency and suggest that latent infection is far more active than first thought. In this review we will focus on new studies that suggest that distinct sites of cellular latency could exist in the human host which, when coupled with recent observations that report different transcriptional programmes within cells of the myeloid lineage, argues for multiple latent phenotypes that could impact differently on the biology of this virus in vivo. Finally, we will also consider how the biology of the host cell where the latent infection persists further contributes to the concept of a spectrum of latent phenotypes in multiple cell types which can be exploited by the virus. PMID:26572645

  2. Avian mycobacteriosis in companion birds: 20-year survey.

    Science.gov (United States)

    Manarolla, Giovanni; Liandris, Emmanouil; Pisoni, Giuliano; Sassera, Davide; Grilli, Guido; Gallazzi, Daniele; Sironi, Giuseppe; Moroni, Paolo; Piccinini, Renata; Rampin, Tiziana

    2009-02-02

    The causative agents of avian mycobacteriosis in pet birds are rarely identified. The aim of this study is to add information about the etiology of avian mycobacteriosis. The identification of mycobacterium species in 27 cases of avian mycobacteriosis in pet birds was investigated by polymerase chain reaction (PCR) and sequencing of a rRNA hypervariable region. Avian mycobacteriosis appeared to be an infrequent diagnosis. Interestingly, a few cases of avian mycobacteriosis were recorded in very young birds. The most commonly affected species were the canary (Serinus canarius), the Eurasian goldfinch (Carduelis carduelis) and the red siskin (Spinus cucullatus). All but one bird were infected with Mycobacterium genavense. Mycobacterium avium was identified only in one case.

  3. Short Stature

    DEFF Research Database (Denmark)

    Christesen, Henrik Boye Thybo; Pedersen, Birgitte Tønnes; Pournara, Effie

    2016-01-01

    The use of appropriate growth standards/references is of significant clinical importance in assessing the height of children with short stature as it may determine eligibility for appropriate therapy. The aim of this study was to determine the impact of using World Health Organization (WHO) instead...... of national growth standards/references on height assessment in short children. Data were collected from routine clinical practice (1998-2014) from nine European countries that have available national growth references and were enrolled in NordiNet® International Outcome Study (IOS) (NCT00960128), a large......-scale, non-interventional, multinational study. The patient cohort consisted of 5996 short pediatric patients diagnosed with growth hormone deficiency (GHD), Turner syndrome (TS) or born small for gestational age (SGA). The proportions of children with baseline height standard deviation score (SDS) below...

  4. Modeling adenovirus latency in human lymphocyte cell lines.

    Science.gov (United States)

    Zhang, Yange; Huang, Wen; Ornelles, David A; Gooding, Linda R

    2010-09-01

    Species C adenovirus establishes a latent infection in lymphocytes of the tonsils and adenoids. To understand how this lytic virus is maintained in these cells, four human lymphocytic cell lines that support the entire virus life cycle were examined. The T-cell line Jurkat ceased proliferation and died shortly after virus infection. BJAB, Ramos (B cells), and KE37 (T cells) continued to divide at nearly normal rates while replicating the virus genome. Viral genome numbers peaked and then declined in BJAB cells below one genome per cell at 130 to 150 days postinfection. Ramos and KE37 cells maintained the virus genome at over 100 copies per cell over a comparable period of time. BJAB cells maintained the viral DNA as a monomeric episome. All three persistently infected cells lost expression of the cell surface coxsackie and adenovirus receptor (CAR) within 24 h postinfection, and CAR expression remained low for at least 340 days postinfection. CAR loss proceeded via a two-stage process. First, an initial loss of cell surface staining for CAR required virus late gene expression and a CAR-binding fiber protein even while CAR protein and mRNA levels remained high. Second, CAR mRNA disappeared at around 30 days postinfection and remained low even after virus DNA was lost from the cells. At late times postinfection (day 180), BJAB cells could not be reinfected with adenovirus, even when CAR was reintroduced to the cells via retroviral transduction, suggesting that the expression of multiple genes had been stably altered in these cells following infection.

  5. assessment of the economic and social implications of the avian flu ...

    African Journals Online (AJOL)

    Admin

    2006-01-22

    Jan 22, 2006 ... KEYWORDS: Assessment, Economic, Social Implications, Avian Flu, Nigerian Poultry. INTRODUCTION. Avian flu is a highly infectious, contagious and zoonotic disease of man, poultry and other birds caused by the avian influenza type A virus, Emmanuel et.al. (2006). The avian influenza virus belongs to ...

  6. New USDA licensed avian influenza vaccine (rHVT-AI) for protection against H5 avian influenza and usage discussion

    Science.gov (United States)

    Recently, a new avian influenza vaccine was licensed by USDA for use in the United States for protection of commercial poultry. The vaccine is a recombinant herpes virus of turkeys expressing the hemagglutinin gene of an H5 subtype avian influenza virus belonging to the 2.2 clade of the H5N1 highly ...

  7. [Epidemiological perspectives on SARS and avian influenza].

    Science.gov (United States)

    del Rey Calero, Juan

    2004-01-01

    SARS is a respiratory infection caused by Coronavirus (Nidoviruses, RNA) from which 3 groups are known. Group 1 affects dogs, cats, pigs, and the human agent is 229 E. Group 2 affects bovines or rodents, and the human agent is OC43. And group 3 corresponds to the avian pathology.... The epidemics emerged on February 2003 in Guangdong, South China, due to consumption of exotic animals (Civeta, etc.), and it spread through interperson contagion to other regions in Asia, America and Europe. Incubation period is about 2-7 days. Transmission Of the virus is person-to person, but also by excretions and residual water. Basic reproductive rate is 2 to 4, and it is considered that 2.7 persons are infected from the initial case. In June 2003, SARS affected over 8,000 people and 774 were killed. Mortality approaches to 10%, and it is higher among older people rising up to 50% in those aged over 65 years. It is important to quickly establish action protocols regarding clinical, epidemiological and prevention aspects. Avian influenza is an infection caused by type A Influenza Orthomixovirus, in which migration birds and wild ducks are the main reservoir. Avian viruses correspond to H5, H7, H9. In 1997 it was observed that type AH5N1 jumped interspecies barrier and affected 18 humans, and 6 of them died. At the end of 2003 and in 2004 this type of poultry flu was described in Asia. FAO has emphasized that sacrifice of chicken in affected farms is the most effective measure to fight against the disease. It has also been established suppression of imports from these countries. There is no evidence on interperson contagion from chicken contagion, nor on food-borne contagion to humans.

  8. The avian transcriptome response to malaria infection.

    Science.gov (United States)

    Videvall, Elin; Cornwallis, Charlie K; Palinauskas, Vaidas; Valkiūnas, Gediminas; Hellgren, Olof

    2015-05-01

    Malaria parasites are highly virulent pathogens which infect a wide range of vertebrates. Despite their importance, the way different hosts control and suppress malaria infections remains poorly understood. With recent developments in next-generation sequencing techniques, however, it is now possible to quantify the response of the entire transcriptome to infections. We experimentally infected Eurasian siskins (Carduelis spinus) with avian malaria parasites (Plasmodium ashfordi), and used high-throughput RNA-sequencing to measure the avian transcriptome in blood collected before infection (day 0), during peak parasitemia (day 21 postinfection), and when parasitemia was decreasing (day 31). We found considerable differences in the transcriptomes of infected and uninfected individuals, with a large number of genes differentially expressed during both peak and decreasing parasitemia stages. These genes were overrepresented among functions involved in the immune system, stress response, cell death regulation, metabolism, and telomerase activity. Comparative analyses of the differentially expressed genes in our study to those found in other hosts of malaria (human and mouse) revealed a set of genes that are potentially involved in highly conserved evolutionary responses to malaria infection. By using RNA-sequencing we gained a more complete view of the host response, and were able to pinpoint not only well-documented host genes but also unannotated genes with clear significance during infection, such as microRNAs. This study shows how the avian blood transcriptome shifts in response to malaria infection, and we believe that it will facilitate further research into the diversity of molecular mechanisms that hosts utilize to fight malaria infections. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  9. Avian magnetic compass: Its functional properties and physical basis

    Directory of Open Access Journals (Sweden)

    Roswitha WILTSCHKO, Wolfgang WILTSCHKO

    2010-06-01

    Full Text Available The avian magnetic compass was analyzed in bird species of three different orders – Passeriforms, Columbiforms and Galliforms – and in three different behavioral contexts, namely migratory orientation, homing and directional conditioning. The respective findings indicate similar functional properties: it is an inclination compass that works only within a functional window around the ambient magnetic field intensity; it tends to be lateralized in favor of the right eye, and it is wavelength-dependent, requiring light from the short-wavelength range of the spectrum. The underlying physical mechanisms have been identified as radical pair processes, spin-chemical reactions in specialized photopigments. The iron-based receptors in the upper beak do not seem to be involved. The existence of the same type of magnetic compass in only very distantly related bird species suggests that it may have been present already in the common ancestors of all modern birds, where it evolved as an all-purpose compass mechanism for orientation within the home range [Current Zoology 56 (3: 265–276, 2010].

  10. Maternal sensitivity and latency to positive emotion following challenge: pathways through effortful control.

    Science.gov (United States)

    Conway, Anne; McDonough, Susan C; Mackenzie, Michael; Miller, Alison; Dayton, Carolyn; Rosenblum, Katherine; Muzik, Maria; Sameroff, Arnold

    2014-01-01

    The ability to self-generate positive emotions is an important component of emotion regulation. In this study, we focus on children's latency to express positive emotions following challenging situations and assess whether this ability operates through early maternal sensitivity and children's effortful control. Longitudinal relations between maternal sensitivity, infant negative affect, effortful control, and latency to positive emotion following challenge were examined in 156 children who were 33 months of age. Structural equation models supported the hypothesis that maternal sensitivity during infancy predicted better effortful control and, in turn, shorter latencies to positive emotions following challenge at 33 months. Directions for future research are discussed. © 2014 Michigan Association for Infant Mental Health.

  11. Prolongation of latencies for passive avoidance responses in rats treated with aniracetam or piracetam.

    Science.gov (United States)

    Yamada, K; Inoue, T; Tanaka, M; Furukawa, T

    1985-04-01

    Effects of aniracetam (1-anysoyl-2-pyrrolodone) and piracetam (1-acetamido-2-pyrrolidone) on passive avoidance behavior were studied in 2 and 18 months old rats using a step-down passive avoidance task. Repeated administration of aniracetam (30 and 50 mg/kg, IP X 5 days) or piracetam (100 mg/kg, IP X 5 days) significantly prolonged step-down latencies for a passive avoidance task in 2 months old rats. Administration of aniracetam (50 mg/kg, IP) or piracetam (100 mg/kg, IP), however, did not affect locomotor activity. This prolongation of latencies was also seen with oral administration of aniracetam (50 mg/kg X 5 days). Similar prolongation of latencies also occurred in 18 months old rat treated with aniracetam (50 mg/kg, IP X 5 days). The results imply that aniracetam may improve learning and/or memory in 2 and 18 months old rats.

  12. Epstein-Barr virus growth/latency III program alters cellular microRNA expression

    International Nuclear Information System (INIS)

    Cameron, Jennifer E.; Fewell, Claire; Yin, Qinyan; McBride, Jane; Wang Xia; Lin Zhen

    2008-01-01

    The Epstein-Barr virus (EBV) is associated with lymphoid and epithelial cancers. Initial EBV infection alters lymphocyte gene expression, inducing cellular proliferation and differentiation as the virus transitions through consecutive latency transcription programs. Cellular microRNAs (miRNAs) are important regulators of signaling pathways and are implicated in carcinogenesis. The extent to which EBV exploits cellular miRNAs is unknown. Using micro-array analysis and quantitative PCR, we demonstrate differential expression of cellular miRNAs in type III versus type I EBV latency including elevated expression of miR-21, miR-23a, miR-24, miR-27a, miR-34a, miR-146a and b, and miR-155. In contrast, miR-28 expression was found to be lower in type III latency. The EBV-mediated regulation of cellular miRNAs may contribute to EBV signaling and associated cancers

  13. Preterm prelabour rupture of membranes: effect of latency on neonatal and maternal outcomes.

    Science.gov (United States)

    Frenette, Priscilla; Dodds, Linda; Armson, B Anthony; Jangaard, Krista

    2013-08-01

    To compare risks of infection and prematurity-related outcomes according to latency periods among women with preterm prelabour rupture of membranes (PPROM). Women with PPROM occurring between 24+0 and 36+6 weeks of gestation were identified from a provincial population-based perinatal database in Nova Scotia. The primary outcomes included composite variables for serious maternal and neonatal infectious morbidity and neonatal prematurity-related morbidity. Logistic regression was used to quantify the relationship between latency period (prematurity-related morbidity were significantly decreased at the latency periods of 48 hours or more compared with prematurity-related morbidity at 48 hours to prematurity-related morbidity, even close to term, without putting mother or neonate at substantial risk for serious infectious morbidity. Generalization of these findings to other obstetric populations should be informed by the underlying risk of infection.

  14. Double sliding-window technique: a new method to calculate the neuronal response onset latency.

    Science.gov (United States)

    Berényi, Antal; Benedek, György; Nagy, Attila

    2007-10-31

    Neuronal response onset latency provides important data on the information processing within the central nervous system. In order to enhance the quality of the onset latency estimation, we have developed a 'double sliding-window' technique, which combines the advantages of mathematical methods with the reliability of standard statistical processes. This method is based on repetitive series of statistical probes between two virtual time windows. The layout of the significance curve reveals the starting points of changes in neuronal activity in the form of break-points between linear segments. A second-order difference function is applied to determine the position of maximum slope change, which corresponds to the onset of the response. In comparison with Poisson spike-train analysis, the cumulative sum technique and the method of Falzett et al., this 'double sliding-window, technique seems to be a more accurate automated procedure to calculate the response onset latency of a broad range of neuronal response characteristics.

  15. The threshold of a stochastic avian-human influenza epidemic model with psychological effect

    Science.gov (United States)

    Zhang, Fengrong; Zhang, Xinhong

    2018-02-01

    In this paper, a stochastic avian-human influenza epidemic model with psychological effect in human population and saturation effect within avian population is investigated. This model describes the transmission of avian influenza among avian population and human population in random environments. For stochastic avian-only system, persistence in the mean and extinction of the infected avian population are studied. For the avian-human influenza epidemic system, sufficient conditions for the existence of an ergodic stationary distribution are obtained. Furthermore, a threshold of this stochastic model which determines the outcome of the disease is obtained. Finally, numerical simulations are given to support the theoretical results.

  16. Crystallization of the C-terminal head domain of the avian adenovirus CELO long fibre

    Energy Technology Data Exchange (ETDEWEB)

    Guardado Calvo, Pablo [Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela (Spain); Llamas-Saiz, Antonio L. [Unidad de Difracción de Rayos X, Laboratorio Integral de Dinámica y Estructura de Biomoléculas José R. Carracido, Edificio CACTUS, Universidad de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela (Spain); Langlois, Patrick [Agence Francaise de Securité Sanitaire des Aliments, Unité Génétique Virale et Biosecurité, Site Les Croix, BP 53, F-22440 Ploufragan (France); Raaij, Mark J. van, E-mail: vanraaij@usc.es [Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela (Spain); Unidad de Difracción de Rayos X, Laboratorio Integral de Dinámica y Estructura de Biomoléculas José R. Carracido, Edificio CACTUS, Universidad de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela (Spain)

    2006-05-01

    Avian adenovirus long-fibre head trimers were expressed, purified and crystallized. The crystals belong to space group C2 (unit-cell parameters a = 216.5, b = 59.2, c = 57.5 Å, β = 101.3°). A complete highly redundant data set was collected to 2.2 Å resolution at 100 K using a rotating-anode X-ray source. Avian adenovirus CELO contains two different fibres: fibre 1, the long fibre, and fibre 2, the short fibre. The short fibre is responsible for binding to an unknown avian receptor and is essential for infection of birds. The long fibre is not essential, but is known to bind the coxsackievirus and adenovirus receptor protein. Both trimeric fibres are attached to the same penton base, of which each icosahedral virus contains 12 copies. The short fibre extends straight outwards, while the long fibre emerges at an angle. The carboxy-terminal amino acids 579–793 of the avian adenovirus long fibre have been expressed with an amino-terminal hexahistidine tag and the expressed trimeric protein has been purified by nickel-affinity chromatography and crystallized. Crystals were grown at low pH using PEG 10 000 as precipitant and belonged to space group C2. The crystals diffracted rotating-anode Cu Kα radiation to at least 1.9 Å resolution and a complete data set was collected from a single crystal to 2.2 Å resolution. Unit-cell parameters were a = 216.5, b = 59.2, c = 57.5 Å, β = 101.3°, suggesting one trimer per asymmetric unit and a solvent content of 46%. The long fibre head does not have significant sequence homology to any other protein of known structure and molecular-replacement attempts with known fibre-head structures were unsuccessful. However, a map calculated using SIRAS phasing shows a clear trimer with a shape similar to known adenovirus fibre-head structures. Structure solution is in progress.

  17. Short communication

    African Journals Online (AJOL)

    Personal

    Short communication. A PRELIMINARY SURVEY OF ERYTHROCEBUS PATAS IN ANBESA CHAKA,. BAMBESI WOREDA OF BENISHANGUL-GUMUZ REGION, WESTERN ETHIOPIA. Solomon Yirga 1, Manyingerew Shenkut 1, .... the guard or watch dog of the group whereas the females are group leaders that initiate ...

  18. Short communication

    African Journals Online (AJOL)

    UPuser

    South African Society for Animal Science. 27. Short communication. Polymorphisms of the CAST gene in the Meishan and five other pig populations in China. Q.S. Wang. 1. , Y.C. Pan. 1#. , L.B. Sun. 2 and H. Meng. 1. 1 Department of Animal Science, School of Agriculture and Biology, Shanghai Jiaotong University, ...

  19. Short Report

    African Journals Online (AJOL)

    2016-10-02

    Oct 2, 2016 ... Short Report. Identifying educational strategies to assess and address the health needs of communities is a high priority, ... using different learning strategies and activities. One such setting is the community, as .... Using the IDEA framework in an interprofessional didactic elective course to facilitate positive ...

  20. Current genomic editing approaches in avian transgenesis.

    Science.gov (United States)

    Park, Tae Sub; Kang, Kyung Soo; Han, Jae Yong

    2013-09-01

    The chicken was domesticated from Red Jungle Fowl over 8000years ago and became one of the major food sources worldwide. At present, the poultry industry is one of the largest industrial animal stocks in the world, and its economic scale is expanding significantly with increasing consumption. Additionally, since Aristotle used chicken eggs as a model to provide remarkable insights into how life begins, chickens have been used as invaluable and powerful experimental materials for studying embryo development, immune systems, biomedical processes, and hormonal regulation. Combined with advancements in efficient transgenic technology, avian models have become even more important than would have been expected. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. USGS highly pathogenic avian influenza research strategy

    Science.gov (United States)

    Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

    2015-09-09

    Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

  2. Avian influenza overview September–November 2017

    DEFF Research Database (Denmark)

    Brown, Ian; Kuiken, Thijs; Mulatti, Paolo

    2017-01-01

    the outbreaks, no transmission to humans has been identified in the EU. The report includes an update of the list of wild bird target species for passive surveillance activities that is based on reported AI-infected wild birds since 2006. The purpose of this list is to provide information on which bird species...... the continuing threat of this avian influenza virus to human health and possible introduction via migratory wild birds into Europe. Close monitoring is required of the situation in Africa with regards to HPAI of the subtypes A(H5N1) and A(H5N8), given the rapidity of the evolution and the uncertainty...

  3. Parathyroid hormone binding to cultured avian osteoclasts

    Energy Technology Data Exchange (ETDEWEB)

    Teti, A.; Rizzoli, R.; Zambonin Zallone, A. (Univ. of Bari (Italy))

    1991-02-14

    Parathyroid hormone (PTH) increases serum calcium concentration via a controversial cellular mechanism. We investigated whether PTH binds avian osteoclasts. Isolated hypocalcaemic hen osteoclasts were incubated with ({sup 125}I)--bovine PTH (1-84). Specific binding of the hormone to the cells, which reached the equilibrium within 60 min, was observed. Half maximal binding was reached by 10 min. Binding was competitively inhibited by increasing doses of unlabeled PTH, and was about 55% displaced by adding, at the equilibrium, 10(-6) M unlabeled PTH. Autoradiography demonstrated specific label on the osteoclast. The cellular mechanism activated by the hormone remains to be elucidated.

  4. Tissue interactions of avian viral attachment proteins

    OpenAIRE

    Ambepitiya Wickramasinghe, I.N.

    2015-01-01

    Viruses can infect a wide range of hosts; varying from bacteria and plants to animals and humans. While many viral infections may pass unnoticed, some are of major importance due to their implications on health and welfare of plants, animals and/or humans. In particular, viruses that can infect avian hosts have been studied intensively due the occurrence of the pandemics of highly pathogenic influenza A virus infection or “bird flu’’. Viral infections in domesticated birds can result in huge ...

  5. Response probability and latency: a straight line, an operational definition of meaning and the structure of short term memory

    OpenAIRE

    Tarnow, Dr. Eugen

    2008-01-01

    The functional relationship between response probability and time is investigated in data from Rubin, Hinton and Wenzel (1999) and Anderson (1981). Recall/recognition probabilities and search times are linearly related through stimulus presentation lags from 6 seconds to 600 seconds in the former experiment and for repeated learning of words in the latter. The slope of the response time vs. probability function is related to the meaningfulness of the items used. The Rubin et al data sugges...

  6. De novo synthesis of VP16 coordinates the exit from HSV latency in vivo.

    Directory of Open Access Journals (Sweden)

    Richard L Thompson

    2009-03-01

    Full Text Available The mechanism controlling the exit from herpes simplex virus latency (HSV is of central importance to recurrent disease and transmission of infection, yet interactions between host and viral functions that govern this process remain unclear. The cascade of HSV gene transcription is initiated by the multifunctional virion protein VP16, which is expressed late in the viral replication cycle. Currently, it is widely accepted that VP16 transactivating function is not involved in the exit from latency. Utilizing the mouse ocular model of HSV pathogenesis together with genetically engineered viral mutants and assays to quantify latency and the exit from latency at the single neuron level, we show that in vivo (i the VP16 promoter confers distinct regulation critical for viral replication in the trigeminal ganglion (TG during the acute phase of infection and (ii the transactivation function of VP16 (VP16TF is uniquely required for the exit from latency. TG neurons latently infected with the VP16TF mutant in1814 do not express detectable viral proteins following stress, whereas viruses with mutations in the other major viral transcription regulators ICP0 and ICP4 do exit the latent state. Analysis of a VP16 promoter/reporter mutant in the background of in1814 demonstrates that the VP16 promoter is activated in latently infected neurons following stress in the absence of other viral proteins. These findings support the novel hypothesis that de novo expression of VP16 regulates entry into the lytic program in neurons at all phases of the viral life cycle. HSV reactivation from latency conforms to a model in which stochastic derepression of the VP16 promoter and expression of VP16 initiates entry into the lytic cycle.

  7. The immunology of human cytomegalovirus latency: could latent infection be cleared by novel immunotherapeutic strategies?

    Science.gov (United States)

    Wills, Mark R; Poole, Emma; Lau, Betty; Krishna, Ben; Sinclair, John H

    2015-01-01

    While the host immune response following primary human cytomegalovirus (HCMV) infection is generally effective at stopping virus replication and dissemination, virus is never cleared by the host and like all herpesviruses, persists for life. At least in part, this persistence is known to be facilitated by the ability of HCMV to establish latency in myeloid cells in which infection is essentially silent with, importantly, a total lack of new virus production. However, although the viral transcription programme during latency is much suppressed, a number of viral genes are expressed during latent infection at the protein level and many of these have been shown to have profound effects on the latent cell and its environment. Intriguingly, many of these latency-associated genes are also expressed during lytic infection. Therefore, why the same potent host immune responses generated during lytic infection to these viral gene products are not recognized during latency, thereby allowing clearance of latently infected cells, is far from clear. Reactivation from latency is also a major cause of HCMV-mediated disease, particularly in the immune compromised and immune naive, and is also likely to be a major source of virus in chronic subclinical HCMV infection which has been suggested to be associated with long-term diseases such as atherosclerosis and some neoplasias. Consequently, understanding latency and why latently infected cells appear to be immunoprivileged is crucial for an understanding of the pathogenesis of HCMV and may help to design strategies to eliminate latent virus reservoirs, at least in certain clinical settings. PMID:25132454

  8. A primary neuron culture system for the study of herpes simplex virus latency and reactivation.

    Science.gov (United States)

    Kobayashi, Mariko; Kim, Ju-Youn; Camarena, Vladimir; Roehm, Pamela C; Chao, Moses V; Wilson, Angus C; Mohr, Ian

    2012-04-02

    Herpes simplex virus type-1 (HSV-1) establishes a life-long latent infection in peripheral neurons. This latent reservoir is the source of recurrent reactivation events that ensure transmission and contribute to clinical disease. Current antivirals do not impact the latent reservoir and there are no vaccines. While the molecular details of lytic replication are well-characterized, mechanisms controlling latency in neurons remain elusive. Our present understanding of latency is derived from in vivo studies using small animal models, which have been indispensable for defining viral gene requirements and the role of immune responses. However, it is impossible to distinguish specific effects on the virus-neuron relationship from more general consequences of infection mediated by immune or non-neuronal support cells in live animals. In addition, animal experimentation is costly, time-consuming, and limited in terms of available options for manipulating host processes. To overcome these limitations, a neuron-only system is desperately needed that reproduces the in vivo characteristics of latency and reactivation but offers the benefits of tissue culture in terms of homogeneity and accessibility. Here we present an in vitro model utilizing cultured primary sympathetic neurons from rat superior cervical ganglia (SCG) (Figure 1) to study HSV-1 latency and reactivation that fits most if not all of the desired criteria. After eliminating non-neuronal cells, near-homogeneous TrkA(+) neuron cultures are infected with HSV-1 in the presence of acyclovir (ACV) to suppress lytic replication. Following ACV removal, non-productive HSV-1 infections that faithfully exhibit accepted hallmarks of latency are efficiently established. Notably, lytic mRNAs, proteins, and infectious virus become undetectable, even in the absence of selection, but latency-associated transcript (LAT) expression persists in neuronal nuclei. Viral genomes are maintained at an average copy number of 25 per neuron

  9. Quiescence Promotes Latent HIV Infection and Resistance to Reactivation from Latency with Histone Deacetylase Inhibitors.

    Science.gov (United States)

    Painter, Mark M; Zaikos, Thomas D; Collins, Kathleen L

    2017-12-15

    Human immunodeficiency virus type 1 (HIV-1) establishes transcriptionally silent latent infections in resting memory T cells and hematopoietic stem and progenitor cells (HSPCs), which allows the virus to persist in infected individuals despite antiretroviral therapy. Developing in vitro models of HIV-1 latency that recapitulate the characteristics of latently infected cells in vivo is crucial to identifying and developing effective latency-reversing therapies. HSPCs exist in a quiescent state in vivo , and quiescence is correlated with latent infections in T cells. However, current models for culturing HSPCs and for infecting T cells in vitro require that the cells be maintained in an actively proliferating state. Here we describe a novel culture system in which primary human HSPCs cultured under hypothermic conditions are maintained in a quiescent state. We show that these quiescent HSPCs are susceptible to predominantly latent infection with HIV-1, while actively proliferating and differentiating HSPCs obtain predominantly active infections. Furthermore, we demonstrate that the most primitive quiescent HSPCs are more resistant to spontaneous reactivation from latency than more differentiated HSPCs and that quiescent HSPCs are resistant to reactivation by histone deacetylase inhibitors or P-TEFb activation but are susceptible to reactivation by protein kinase C (PKC) agonists. We also demonstrate that inhibition of HSP90, a known regulator of HIV transcription, recapitulates the quiescence and latency phenotypes of hypothermia, suggesting that hypothermia and HSP90 inhibition may regulate these processes by similar mechanisms. In summary, these studies describe a novel model for studying HIV-1 latency in human primary cells maintained in a quiescent state. IMPORTANCE Human immunodeficiency virus type 1 (HIV-1) establishes a persistent infection for which there remains no feasible cure. Current approaches are unable to clear the virus despite decades of therapy due

  10. An Ultra-Low-Latency Geo-Routing Scheme for Team-Based Unmanned Vehicular Applications

    KAUST Repository

    Bader, Ahmed

    2016-02-26

    Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile systems whereby a cluster of unmanned autonomous vehicles are deployed to accomplish a critical mission under human supervision. The contention-free nature of the developed scheme lends itself to jointly achieve lower latency and higher throughput. Implementation challenges are presented and corresponding resolutions are discussed herewith. © 2015 IEEE.

  11. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The principal results of studies on crisis stability, deterrence, and latency are presented in their order of development. They capture the main features of stability analysis; relate first strike, crisis, and arms control stability as seen from US and Russian perspective; and address whether different metrics, uncertain damage preferences, or the deployment of defenses can be destabilizing. The report explores differences between unilateral and proportional force reductions in the region of deep reductions where concern shifts from stability to latency.

  12. Optimized Interface Diversity for Ultra-Reliable Low Latency Communication (URLLC)

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Liu, Rongkuan; Popovski, Petar

    2017-01-01

    An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use interface diversity and integrate multiple communication interfaces, each interface based on a different...... technology. Our approach is to use rateless codes to seamlessly distribute coded payload and redundancy data across multiple available communication interfaces. We formulate an optimization problem to find the payload allocation weights that maximize the reliability at specific target latency values...

  13. Parametric inference of neuronal response latency in presence of a background signal

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano; Ditlevsen, Susanne; Lansky, Petr

    2013-01-01

    Neurons are commonly characterized by spontaneous generation of action potentials (spikes), which appear without any apparent or controlled stimulation. When a stimulus is applied, the spontaneous firing may prevail and hamper identification of the effect of the stimulus. Therefore, for any...... will persist even when sample size is increasing. The first question is: what is the response latency to the stimulus? Answering this question becomes even more difficult if the latency is of a complex nature, for example composed of a physically implied deterministic part and a stochastic part. This scenario...

  14. Influence of ageing on carotid baroreflex peak response latency in humans

    DEFF Research Database (Denmark)

    Fisher, J.P.; Kim, A.; Young, C.N.

    2009-01-01

    The stability of a physiological control system, such as the arterial baroreflex, depends critically upon both the magnitude (i.e. gain or sensitivity) and timing (i.e. latency) of the effector response. Although studies have examined resting arterial baroreflex sensitivity in older subjects......, little attention has been given to the influence of ageing on the latency of peak baroreflex responses. First, we compared the temporal pattern of heart rate (HR) and mean arterial blood pressure (BP) responses to selective carotid baroreceptor (CBR) unloading and loading in 14 young (22 +/- 1 years...

  15. Avian-like breathing mechanics in maniraptoran dinosaurs.

    Science.gov (United States)

    Codd, Jonathan R; Manning, Phillip L; Norell, Mark A; Perry, Steven F

    2008-01-22

    In 1868 Thomas Huxley first proposed that dinosaurs were the direct ancestors of birds and subsequent analyses have identified a suite of 'avian' characteristics in theropod dinosaurs. Ossified uncinate processes are found in most species of extant birds and also occur in extinct non-avian maniraptoran dinosaurs. Their presence in these dinosaurs represents another morphological character linking them to Aves, and further supports the presence of an avian-like air-sac respiratory system in theropod dinosaurs, prior to the evolution of flight. Here we report a phylogenetic analysis of the presence of uncinate processes in Aves and non-avian maniraptoran dinosaurs indicating that these were homologous structures. Furthermore, recent work on Canada geese has demonstrated that uncinate processes are integral to the mechanics of avian ventilation, facilitating both inspiration and expiration. In extant birds, uncinate processes function to increase the mechanical advantage for movements of the ribs and sternum during respiration. Our study presents a mechanism whereby uncinate processes, in conjunction with lateral and ventral movements of the sternum and gastral basket, affected avian-like breathing mechanics in extinct non-avian maniraptoran dinosaurs.

  16. Collapsing avian community on a Hawaiian island

    Science.gov (United States)

    Paxton, Eben H.; Camp, Richard J.; Gorresen, P. Marcos; Crampton, Lisa H.; Leonard, David L.; VanderWerf, Eric

    2016-01-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing.

  17. Developmental studies of avian brain organization.

    Science.gov (United States)

    Puelles, Luis

    2018-01-01

    Avian brain organization or brain Bauplan is identical with that of vertebrates in general. This essay visits avian studies that contained advances or discussions about brain organization, trying to explain critically what they contributed. In order to start from a specific background, the new prevailing paradigm as regards brain organization, the prosomeric model, is presented first. Next a brief historic survey is made of how ideas on this topic evolved from the start of modern neuromorphology at the end of the 19th century. Longitudinal zonal organization with or without transverse segmentation (neuromeres) was the first overall concept applied to the brain. The idea of neuromeric structure later decayed in favour of a columnar model. This emphasized functional correlations rather than causal developmental content, assimilating forebrain functions to hindbrain ones. Though it became prevalent in the post-world-war period of neuroscience, in the last decades of the 20th century advances in molecular biology allowed developmental genes to be mapped, and it became evident that gene expression patterns support the old neuromeric model rather than the columnar one. This was also corroborated by modern experimental approaches (fate-mapping and analysis of patterning).

  18. Seasonal change in the avian hippocampus.

    Science.gov (United States)

    Sherry, David F; MacDougall-Shackleton, Scott A

    2015-04-01

    The hippocampus plays an important role in cognitive processes, including memory and spatial orientation, in birds. The hippocampus undergoes seasonal change in food-storing birds and brood parasites, there are changes in the hippocampus during breeding, and further changes occur in some species in association with migration. In food-storing birds, seasonal change in the hippocampus occurs in fall and winter when the cognitively demanding behaviour of caching and retrieving food occurs. The timing of annual change in the hippocampus of food-storing birds is quite variable, however, and appears not to be under photoperiod control. A variety of factors, including cognitive performance, exercise, and stress may all influence seasonal change in the avian hippocampus. The causal processes underlying seasonal change in the avian hippocampus have not been extensively examined and the more fully described hormonal influences on the mammalian hippocampus may provide hypotheses for investigating the control of hippocampal seasonality in birds. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. PATHOMORPHOLOGICAL AND HISTOPATHOLOGICAL CHANGES OF AVIAN CHLAMYDIOSIS

    Directory of Open Access Journals (Sweden)

    Edin Šatrović

    2013-01-01

    Full Text Available Avian chlamydiosis is an infectious disease of birds caused by gram-negative bacterium Chlamydophila psittaci. However, this disease can occure among other mammals including humans. Chlamydiosis often presents as an inapparent infection, especially in older birds. During stressful conditions (deficient diet, transportation, great population density in small spaces, etc. and comorbidity, however, the birds usually begin to either present with the clinical signs of chlamydiosis, or secrete many causative agents to the environment. Depending on the serotype of the causative agent, and the type and age of the host, the disease usually causes systemic disorders, and is often fatal. The affected birds present with lethargy, fever, typical yellow-green discharge from the eyes and nose, diarrhea, anorexia and the weight lost. Bearing capacity is reduced. Autopsy findings show hepatomegaly with necrotic foci, splenomegaly and fibrinous inflammation of the pericardium, peritoneum and air sacs. Pathohistological findings reveal elementary bodies in the intercellular space dyed red to reddish purple using the Gimenez technique.Key words: avian chlamydiosis, pathomorphological changes, histopathological changes

  20. Avian colibacillosis: still many black holes.

    Science.gov (United States)

    Guabiraba, Rodrigo; Schouler, Catherine

    2015-08-01

    Avian pathogenic Escherichia coli (APEC) strains cause severe respiratory and systemic diseases, threatening food security and avian welfare worldwide. Intensification of poultry production and the quick expansion of free-range production systems will increase the incidence of colibacillosis through greater exposure of birds to pathogens and stress. Therapy is mainly based on antibiotherapy and current vaccines have poor efficacy. Serotyping remains the most frequently used diagnostic method, only allowing the identification of a limited number of APEC strains. Several studies have demonstrated that the most common virulence factors studied in APEC are all rarely present in the same isolate, showing that APEC strains constitute a heterogeneous group. Different isolates may harbor different associations of virulence factors, each one able to induce colibacillosis. Despite its economical relevance, pathogenesis of colibacillosis is poorly understood. Our knowledge on the host response to APEC is based on very descriptive studies, mostly restricted to bacteriological and histopathological analysis of infected organs such as lungs. Furthermore, only a small number of APEC isolates have been used in experimental studies. In the present review, we discuss current knowledge on APEC diversity and virulence, including host response to infection and the associated inflammatory response with a focus on pulmonary colibacillosis. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Functional window of the avian compass.

    Science.gov (United States)

    Poonia, Vishvendra Singh; Kondabagil, Kiran; Saha, Dipankar; Ganguly, Swaroop

    2017-05-01

    The functional window is an experimentally observed property of the avian compass that refers to its selectivity around the geomagnetic-field strength. We show that the simple radical-pair model, using biologically feasible hyperfine parameters, can qualitatively explain the salient features of the avian compass as observed in behavioral experiments: its functional window, as well as disruption of the compass action by radio-frequency fields of specific frequencies. Further, we show that adjustment of the hyperfine parameters can tune the functional window, suggesting a possible mechanism for its observed adaptation to field variation. While these lend support to the radical-pair model, we find that in its simplest form-or even with minor augmentations-it cannot quantitatively explain the observed width of the functional window. This suggests deeper generalization of the model, possibly in terms of more nuclei or more subtle environmental interaction than has been considered hitherto. Finally, we examine a possible biological purpose for the functional window; even assuming evolutionary benefit from radical-pair magnetoreception, it seems likely that the functional window could be just a corollary thereof, imparting no additional advantage.

  2. Milestones in avian coccidiosis research: a review.

    Science.gov (United States)

    Chapman, H D

    2014-03-01

    This article describes some of the milestones in research concerned with protozoan parasites of the genus Eimeria that infect birds and cause the disease coccidiosis. The time period covered is from 1891, when oocysts were first found in the ceca of diseased chickens, to the present. Progress in our understanding has lagged behind that of other protozoan parasites such as Toxoplasma and Plasmodium despite the enormous importance of Eimeria to animal livestock production. Nevertheless, applied research by universities, government agencies, and private industry has resulted in the successful development of methods of control, research that continues today. The topics covered and the references provided are selective and include life cycles and biology, pathology, ultrastructure, biochemistry, immunity, genetics, host cell invasion, species identification, taxonomy, chemotherapy, vaccination, and literature concerned with avian coccidiosis. This review is primarily concerned with the avian species of Eimeria that infect poultry, but some important advances, principally in immunology, have been made using species that infect rodents and rabbits. These are included where appropriate.

  3. Replication of avian influenza A viruses in mammals.

    OpenAIRE

    Hinshaw, V S; Webster, R G; Easterday, B C; Bean, W J

    1981-01-01

    The recent appearance of an avian influenza A virus in seals suggests that viruses are transmitted from birds to mammals in nature. To examine this possibility, avian viruses of different antigenic subtypes were evaluated for their ability to replicate in three mammals-pigs, ferrets, and cats. In each of these mammals, avian strains replicated to high titers in the respiratory tract (10(5) to 10(7) 50% egg infective doses per ml of nasal wash), with peak titers at 2 to 4 days post-inoculation...

  4. Data base on avian mortality on man-made structures

    Energy Technology Data Exchange (ETDEWEB)

    Dailey, N. S.

    1978-01-01

    A computerized data base concerning avian mortality on man-made structures is available for searching at the Ecological Sciences Information Center of the Information Center Complex, Information Division, Oak Ridge National Laboratory. This data base, which contains entries from the available literature, provides information on avian mortality from either collision into or electrocution on man-made structures. Primary emphasis has been placed on avian collision with obstacles such as television and radio towers, airport ceilometers, transmission lines, and cooling towers. Other structures included in the studies are fences, glass walls and windows, lighthouses, telegraph and telephone wires, buildings, monuments, smokestacks, and water towers.

  5. Comparative genomics reveals insights into avian genome evolution and adaptation

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Cai; Li, Qiye

    2014-01-01

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size...... this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits....

  6. Punctured Scheduling for Critical Low Latency Data on a Shared Channel with Mobile Broadband

    DEFF Research Database (Denmark)

    Pedersen, Klaus I.; Gerardino, Guillermo Andrés Pocovi; Steiner, Jens

    2017-01-01

    In this paper, we present a punctured scheduling scheme for efficient transmission of low latency communication (LLC) traffic, multiplexed on a downlink shared channel with enhanced mobile broadband traffic (eMBB). Puncturing allows to schedule eMBB traffic on all shared channel resources, without...

  7. The role of latency period in quality management for free-breathing coronary wall MRI.

    Science.gov (United States)

    Lin, Kai; Lloyd-Jones, Donald M; Liu, Ying; Bi, Xiaoming; Lu, Biao; Li, Debiao; Carr, James C

    2015-03-01

    The aim of the present study was to determine the effects of the latency period on the performance of free-breathing coronary wall MRI. With the approval of IRB, 70 participants were recruited for coronary wall magnetic resonance imaging (MRI) and provided written informed consent. In 35 subjects, right coronary segments (RCA1-3) were imaged first; in the remaining subjects, the left coronary segments (LM and LAD1-3) were imaged first. The images were classified into groups; group 1 contained right coronary images from the subjects whose right coronary segments were imaged first and left coronary images from the subjects whose left coronary segments were imaged first. Group 2 contained the other coronary segments. The image scores (ranked1-3), latency periods, drift of the position of the navigator (NAV), scan efficiency were compared between image groups. Image group 1 has higher scores (1.66 ± 0.55 vs. 1.46 ± 0.51), shorter latency periods (32.04 ± 4.24 vs. 44.22 ± 5.57 min), lower drift in the location of the NAV (1.90 ± 1.27 mm vs. 2.61 ± 1.71 mm) and higher scan efficiency (32.7 ± 7.6 vs. 29.9 ± 7.9%) than group 2. Long latency periods have a significantly negative impact on the image quality of coronary wall MRI.

  8. Reversible silencing of cytomegalovirus genomes by type I interferon governs virus latency.

    Directory of Open Access Journals (Sweden)

    Franziska Dağ

    2014-02-01

    Full Text Available Herpesviruses establish a lifelong latent infection posing the risk for virus reactivation and disease. In cytomegalovirus infection, expression of the major immediate early (IE genes is a critical checkpoint, driving the lytic replication cycle upon primary infection or reactivation from latency. While it is known that type I interferon (IFN limits lytic CMV replication, its role in latency and reactivation has not been explored. In the model of mouse CMV infection, we show here that IFNβ blocks mouse CMV replication at the level of IE transcription in IFN-responding endothelial cells and fibroblasts. The IFN-mediated inhibition of IE genes was entirely reversible, arguing that the IFN-effect may be consistent with viral latency. Importantly, the response to IFNβ is stochastic, and MCMV IE transcription and replication were repressed only in IFN-responsive cells, while the IFN-unresponsive cells remained permissive for lytic MCMV infection. IFN blocked the viral lytic replication cycle by upregulating the nuclear domain 10 (ND10 components, PML, Sp100 and Daxx, and their knockdown by shRNA rescued viral replication in the presence of IFNβ. Finally, IFNβ prevented MCMV reactivation from endothelial cells derived from latently infected mice, validating our results in a biologically relevant setting. Therefore, our data do not only define for the first time the molecular mechanism of IFN-mediated control of CMV infection, but also indicate that the reversible inhibition of the virus lytic cycle by IFNβ is consistent with the establishment of CMV latency.

  9. Evaluation of DECT for low latency real-time industrial control networks

    NARCIS (Netherlands)

    Das, Kallol; Havinga, Paul J.M.

    2013-01-01

    Wireless sensor networks (WSNs) have revolutionized the industrial networks by enabling wireless sensing and control to the machine parts where wiring is impossible. However, new challenges in terms of communication reliability and latency, appear with the advances in the industrial wireless control

  10. Without Latency: Cathode Immersions and the Neglected Practice of Xenocasting for Television and Radio

    NARCIS (Netherlands)

    Hulbert, Adam

    2015-01-01

    abstractThis paper discusses a three-year radio project Cathode Immersions, which was aired on 2SER in Sydney Australia. The audio that accompanied free-to-air television was remixed and rebroadcast in real time without latency. It explores the human and non-human aspects of the convergence of these

  11. A quantitative technique for the study of the latency of Aujeszky virus.

    Science.gov (United States)

    Schang, L M; Osorio, F A

    1993-06-01

    Latency represents a challenge for any herpesvirus vaccine. Vaccines could differ in their ability to minimize latency of pseudorabies virus (PRV). To study this possibility, a quantitative and differential PRV-specific polymerase chain reaction (PCR) was developed by the authors. Efficiency of amplification in different tubes is measured by co-amplification with the viral targets (either gI or gp50 genes) of the porcine gene nuclear factor 1. The criteria used to select this approach to a quantitative PCR, as well as for the selection of the standard, are discussed. The amplified products are measured by Southern blot or, alternatively, high performance liquid chromatography. Sensitivity and reproducibility of the technique are evaluated. The ability of this technique to discriminate between the level of latency established by two different PRV strains in trigeminal ganglia is also evaluated. Using this technique, the authors are currently studying whether different vaccines could possess differing levels of ability to minimize, by interference, establishment of wild-type latency.

  12. Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks

    Science.gov (United States)

    Anwar, Farhat; Masud, Mosharrof H.; Latif, Suhaimi A.

    2013-12-01

    Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6.

  13. Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks

    International Nuclear Information System (INIS)

    Anwar, Farhat; Masud, Mosharrof H; Latif, Suhaimi A

    2013-01-01

    Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6

  14. PRINCE - A Low-Latency Block Cipher for Pervasive Computing Applications: Extended Abstract

    DEFF Research Database (Denmark)

    Borghoff, J.; Canteaut, Anne Michele; Guneysu, T.

    2012-01-01

    his paper presents a block cipher that is optimized with respect to latency when implemented in hardware. Such ciphers are desirable for many future pervasive applications with real-time security needs. Our cipher, named PRINCE, allows encryption of data within one clock cycle with a very...

  15. Auditory Processing in Dyslexia: Middle Latency Event-Related Potentials and Temporal Sequencing.

    Science.gov (United States)

    Krull, Kevin R.

    Behavioral and electrophysiological processing of sequential tones were investigated in reading delayed (RD) and non-reading delayed (NRD) children matched on intelligence and reading level. NRD children performed consistently better on sequencing of tonal patterns. Middle latency event-related potentials from the RD group indicated reduced…

  16. Flash Memory Reliability: Read, Program, and Erase Latency Versus Endurance Cycling

    Science.gov (United States)

    Heidecker, Jason

    2010-01-01

    This report documents the efforts and results of the fiscal year (FY) 2010 NASA Electronic Parts and Packaging Program (NEPP) task for nonvolatile memory (NVM) reliability. This year's focus was to measure latency (read, program, and erase) of NAND Flash memories and determine how these parameters drift with erase/program/read endurance cycling.

  17. Neuromagnetic Oscillations Predict Evoked-Response Latency Delays and Core Language Deficits in Autism Spectrum Disorders

    Science.gov (United States)

    Edgar, J. Christopher; Khan, Sarah Y.; Blaskey, Lisa; Chow, Vivian Y.; Rey, Michael; Gaetz, William; Cannon, Katelyn M.; Monroe, Justin F.; Cornew, Lauren; Qasmieh, Saba; Liu, Song; Welsh, John P.; Levy, Susan E.; Roberts, Timothy P. L.

    2015-01-01

    Previous studies have observed evoked response latency as well as gamma band superior temporal gyrus (STG) auditory abnormalities in individuals with autism spectrum disorders (ASD). A limitation of these studies is that associations between these two abnormalities, as well as the full extent of oscillatory phenomena in ASD in terms of frequency…

  18. Predictive factors for latency period in viable pregnancies complicated by preterm premature rupture of the membranes.

    Science.gov (United States)

    Çetin, Cihan; Büyükkurt, Selim; Cömert, Ercan; Özlü, Ferda; Bahar, Nilgün; Demir, Cansun

    2015-03-01

    In this study, we aimed to evaluate some laboratory and clinical factors in the prediction of latency period for pregnant patients complicated with preterm premature rupture of the membranes. Sixty-five pregnant patients between 24 and 34 weeks of gestation, who were admitted to University of Çukurova School of Medicine Hospital with the diagnosis of preterm premature rupture of the membranes (PPROM) between January 01, 2013 and December 31, 2013, were included in this study. Serum CRP, procalcitonin, sedimentation rate, leukocyte count and cervical length (measured with transvaginal ultrasound) of patients were analyzed for the correlation with the latency period. None of the parameters were found to be correlated with the latency period. However, patients with cervical length of premature rupture of the membranes is thought to be either an infection-based disease or a disease increasing the risk of infectious complications, major infection markers are not found to be helpful criteria for the prediction of latency period. Patients with a cervical length of <25 mm can be expected to deliver earlier and, therefore, can be referred to a tertiary center earlier.

  19. An Optimized WSN Design for Latency-Critical Smart Grid Applications

    Directory of Open Access Journals (Sweden)

    Mounib Khanafer

    2017-01-01

    Full Text Available The growing popularity of the Internet of Things (IoT systems such as the smart grid, Body Area Networks (BANs, and the Intelligent Transportation System (ITS is driving Wireless Sensor Network (WSN systems to the limit in terms of abilities and performance. WSNs were initially designed for low power, low data rate, and latency-tolerant applications. However, this paradigm is changing because of the nature of the new applications. Therefore, instead of only focusing on power-efficient WSN design, researchers and industries are now developing Quality of Service (QoS protocols for WSNs. In addition to that, latency- and reliability-critical protocol designs are also becoming significantly important in WSNs. In this paper, we present an overview of some important smart grid latency-critical applications and highlight WSNs implementation challenges for these smart grid applications. Furthermore, we develop and evaluate two novel optimization models that solve for the optimum values of the end-to-end latency and power consumption in a clustered WSN given lower bounds on reliability and other network parameters.

  20. Effects of latency period on aspects of the reproductive biology of ...

    African Journals Online (AJOL)

    Heterobranchus longifilisbroodstock were procured, acclimatized and hypophycised with ovaprim. Eggs were stripped from the females between 8 and17 hrs. After hypophysation, while milt was obtained from the males by dissection. Proliferation and ease of flow of eggs were observed as the latency period increased.

  1. Act quickly, decide later: long-latency visual processing underlies perceptual decisions but not reflexive behavior.

    Science.gov (United States)

    Jolij, Jacob; Scholte, H Steven; van Gaal, Simon; Hodgson, Timothy L; Lamme, Victor A F

    2011-12-01

    Humans largely guide their behavior by their visual representation of the world. Recent studies have shown that visual information can trigger behavior within 150 msec, suggesting that visually guided responses to external events, in fact, precede conscious awareness of those events. However, is such a view correct? By using a texture discrimination task, we show that the brain relies on long-latency visual processing in order to guide perceptual decisions. Decreasing stimulus saliency leads to selective changes in long-latency visually evoked potential components reflecting scene segmentation. These latency changes are accompanied by almost equal changes in simple RTs and points of subjective simultaneity. Furthermore, we find a strong correlation between individual RTs and the latencies of scene segmentation related components in the visually evoked potentials, showing that the processes underlying these late brain potentials are critical in triggering a response. However, using the same texture stimuli in an antisaccade task, we found that reflexive, but erroneous, prosaccades, but not antisaccades, can be triggered by earlier visual processes. In other words: The brain can act quickly, but decides late. Differences between our study and earlier findings suggesting that action precedes conscious awareness can be explained by assuming that task demands determine whether a fast and unconscious, or a slower and conscious, representation is used to initiate a visually guided response.

  2. Extending the permissible control loop latency for the controlled inverted pendulum

    NARCIS (Netherlands)

    Sieber, J.; Krauskopf, B.

    2005-01-01

    A pendulum can be stabilized in its upright position by proportional-plus-derivative (PD) feedback control only if the latency in the control loop is smaller than a certain critical delay. This critical delay is determined by the presence of a fully symmetric triple-zero eigenvalue singularity, a

  3. Changes in the Motor and Sensory Latencies of Median Nerve According to Age

    Directory of Open Access Journals (Sweden)

    HR Elmi

    2006-10-01

    Full Text Available Introduction: Even though there is a high prevalence of carpal tunnel syndrome patients, there are very few reliable papers on the study of normal values and changes in sensory and motor latency parameters of the median nerve in the wrist region on the basis of age of patients .This retrospective study was on the basis of 5 years data (1998 -2003 from the electro diagnostic department of Sh. Sadoughi teaching hospital of Yazd. Methods: In this analytic and observational study, subjects included 1200 patients referring to the electrodiagnostic clinic and also randomly selected healthy patients. Exclusion criteria included systemic diseases such as diabetes, radiculopathy of cervical spine , peripheral neuropathy , positive Phallen test or Tinel sign and atrophy in the thenar region of the hand. Subjects were divided to ten groups on the basis of age. ( 10-80 years Sensory and motor latency parameters of median nerve were studied in each age group. All data was evaluated using SPSS statistical software and ANOVA , LSDREST curve regression tests were used for analysis. All values less than 0.05 were considered significant. Results: In this study, normal values for distal motor latency of median nerve were between 2.5-4.2ms with a ±2SD and mean value of 3.3ms. Increment in this value was mild (0.1ms per decade after 5th decade of life. This value was calculated using the formula: Distal motor latency: Normal value for distal sensory latency of median nerve was 2.7-3.7ms with a ±2SD and mean value of 3.2ms. Increment in this value also was 0.1ms per decade after 5th decade of life. This value was calculated by the formula: Distal sensory latency: Conclusion: It seems that age has a meaningful relationship with distal motor and sensory latencies in the wrist region and therefore in the future, electro diagnostic evaluation along with other increments in these parameters according to age should be considered when evaluating patients with carpal

  4. Tracking latency in image-based dynamic MLC tracking with direct image access.

    Science.gov (United States)

    Fledelius, Walther; Keall, Paul J; Cho, Byungchul; Yang, Xinhui; Morf, Daniel; Scheib, Stefan; Poulsen, Per R

    2011-08-01

    Target tracking is a promising method for motion compensation in radiotherapy. For image-based dynamic multileaf collimator (DMLC) tracking, latency has been shown to be the main contributor to geometrical errors in tracking of respiratory motion, specifically due to slow transfer of image data from the image acquisition system to the tracking system via image file storage on a hard disk. The purpose of the current study was to integrate direct image access with a DMLC tracking system and to quantify the tracking latency of the integrated system for both kV and MV image-based tracking. A DMLC tracking system integrated with a linear accelerator was used for tracking of a motion phantom with an embedded tungsten marker. Real-time target localization was based on x-ray images acquired either with a portal imager or a kV imager mounted orthogonal to the treatment beam. Images were processed directly without intermediate disk access. Continuous portal images and system log files were stored during treatment delivery for detailed offline analysis of the tracking latency. The mean tracking system latency for kV and MV image-based tracking as function of the imaging interval ΔT(image) increased linearly with ΔT(image) as 148 ms + 0.58 * ΔT(image) (kV) and 162 ms + 1.1 * ΔT(image) (MV). The latency contribution from image acquisition and image transfer for kV image-based tracking was independent on ΔT(image) at 103 ± 14 ms. For MV-based tracking, it increased with ΔT(image) as 124 ms + 0.44 * ΔT(image). For ΔT(image) = 200 ms (5 Hz imaging), the total latency was reduced from 550 ms to 264 ms for kV image-based tracking and from 500 ms to 382 ms for MV image-based tracking as compared to the previously used indirect image transfer via image file storage on a hard disk. kV and MV image-based DMLC tracking was successfully integrated with direct image access. It resulted in substantial tracking latency reductions compared with image-based tracking without direct

  5. Reprint of: Overview of avian toxicity studies for the Deepwater Horizon Natural Resource Damage Assessment

    Science.gov (United States)

    Bursian, Steven J.; Alexander, C.R.; Cacela, Dave; Cunningham, Fred L.; Dean, Karen M.; Dorr, Brian S.; Ellis, Christine K.; Godard-Codding, Céline A.J.; Guglielmo, Christopher G.; Hanson-Dorr, Katie C.; Harr, Kendall E.; Healy, Katherine A.; Hooper, Michael J.; Horak, Katherine E.; Isanhart, John P.; Kennedy, Lisa V.; Link., Jane E.; Maggini, Ivan; Moye, John K.; Perez, Christina R.; Pritsos, Chris A.; Shriner, Susan A.; Trust, Kinberly A.; Tuttle, Peter L.

    2017-01-01

    The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1–20 ml of artificially weathered Mississippi Canyon 252 oil kg bw-1 day-1 from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts

  6. The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task

    Directory of Open Access Journals (Sweden)

    Maciej ePerdziak

    2014-10-01

    Full Text Available The term amblyopia is used to describe reduced visual function in one eye (or both eyes, though not so often which cannot be fully improved by refractive correction and explained by the organic cause observed during regular eye examination. This developmental disorder of spatial vision affects about 2-5% of the population and is associated with abnormal visual experience (e.g. anisometropia, strabismus during infancy or early childhood. Several studies have shown prolongation of saccadic latency time in amblyopic eye. In our opinion, study of saccadic latency in the context of central vision deficits assessment, should be based on central retina stimulation. For this reason, we proposed saccade delayed task. It requires inhibitory processing for maintaining fixation on the central target until it disappears – what constitutes the GO signal for saccade. The experiment consisted of 100 trials for each eye and was performed under two viewing conditions: monocular amblyopic / non-dominant eye and monocular dominant eye. We examined saccadic latency in 16 subjects (mean age 30±11 years with anisometropic amblyopia (two subjects had also microtropia and in 17 control subjects (mean age 28±8 years. Participants were instructed to look at central (fixation target and when it disappears, to make the saccade toward the periphery (10 deg as fast as possible, either left or the right target. The study results have proved the significant difference in saccadic latency between the amblyopic (mean 262±48 ms and dominant (mean 237±45 ms eye, in anisometropic group. In the control group, the saccadic latency for dominant (mean 226±32ms and non-dominant (mean 230±29 ms eye was not significantly different.By the use of LATER (Linear Approach to the Threshold with Ergodic Rate decision model we interpret our findings as a decrease in accumulation of visual information acquired by means of central (affected retina in subjects with anisometropic amblyopia.

  7. Tap Arduino: An Arduino microcontroller for low-latency auditory feedback in sensorimotor synchronization experiments.

    Science.gov (United States)

    Schultz, Benjamin G; van Vugt, Floris T

    2016-12-01

    Timing abilities are often measured by having participants tap their finger along with a metronome and presenting tap-triggered auditory feedback. These experiments predominantly use electronic percussion pads combined with software (e.g., FTAP or Max/MSP) that records responses and delivers auditory feedback. However, these setups involve unknown latencies between tap onset and auditory feedback and can sometimes miss responses or record multiple, superfluous responses for a single tap. These issues may distort measurements of tapping performance or affect the performance of the individual. We present an alternative setup using an Arduino microcontroller that addresses these issues and delivers low-latency auditory feedback. We validated our setup by having participants (N = 6) tap on a force-sensitive resistor pad connected to the Arduino and on an electronic percussion pad with various levels of force and tempi. The Arduino delivered auditory feedback through a pulse-width modulation (PWM) pin connected to a headphone jack or a wave shield component. The Arduino's PWM (M = 0.6 ms, SD = 0.3) and wave shield (M = 2.6 ms, SD = 0.3) demonstrated significantly lower auditory feedback latencies than the percussion pad (M = 9.1 ms, SD = 2.0), FTAP (M = 14.6 ms, SD = 2.8), and Max/MSP (M = 15.8 ms, SD = 3.4). The PWM and wave shield latencies were also significantly less variable than those from FTAP and Max/MSP. The Arduino missed significantly fewer taps, and recorded fewer superfluous responses, than the percussion pad. The Arduino captured all responses, whereas at lower tapping forces, the percussion pad missed more taps. Regardless of tapping force, the Arduino outperformed the percussion pad. Overall, the Arduino is a high-precision, low-latency, portable, and affordable tool for auditory experiments.

  8. Development of the Plate Boundary Observatory GPS Low Latency Salton Trough Radio Network

    Science.gov (United States)

    Walls, C.; Miller, S.; Wilson, B.; Lawrence, S.; Arnitz, E.

    2008-05-01

    UNAVCO is developing a 20 GPS station low latency radio network that spans the San Andreas and San Jacinto faults in the region of highest strain in southern California and the narrowest part of the North America-Pacific plate boundary. The Salton Trough Radio Network (STRN) is instrumented with Ethernet bridge Intuicom EB6+ (900 MHz) radios to transmit a high rate low latency data stream from each permanent GPS site for the purpose of the following: 1) telemeter 15 second data (1 MB/day/station) to the Plate Boundary Observatory archive, 2) accommodate the timely download of 1 and 5 sample per second data following large earthquakes (4 MB/hour/station), and 3) test the UStream of 1Hz BINEX and RTCM data. Three of four phases have been completed. Office radio testing yielded transfer rates of 30-50 KB/s with subsecond latency while streaming 1 Hz data. Latency climbed to ~1.8 seconds while simultaneously streaming 1 Hz and downloading hourly 1 and 5 sample per second data files. Field testing demonstrated rates on the order of 30 KB/s. At present the radios are installed and have transfer rates of 10-40 KB/s between sites that span 10-32 km. The final phase will be the installation of the main telemetry relay where master radios will be connected to a high speed ISP near the town of Brawley. The high-rate low latency UStream data will be available to researchers who are developing prototype earthquake early warning systems in Southern California. A goal of the STRN is to make the data available rapidly enough for GPS-derived coseismic and dynamic displacements to be integrated into early warning system earthquake models. The improved earthquake models will better assist emergency response. UStream data will also aid surveyors who wish to use PBO GPS stations as permanent, high-quality base stations in real-time kinematic surveys.

  9. Understanding and Analyzing Latency of Near Real-time Satellite Data

    Science.gov (United States)

    Han, W.; Jochum, M.; Brust, J.

    2016-12-01

    Acquiring and disseminating time-sensitive satellite data in a timely manner is much concerned by researchers and decision makers of weather forecast, severe weather warning, disaster and emergency response, environmental monitoring, and so on. Understanding and analyzing the latency of near real-time satellite data is very useful and helpful to explore the whole data transmission flow, indentify the possible issues, and connect data providers and users better. The STAR (Center for Satellite Applications and Research of NOAA) Central Data Repository (SCDR) is a central repository to acquire, manipulate, and disseminate various types of near real-time satellite datasets to internal and external users. In this system, important timestamps, including observation beginning/end, processing, uploading, downloading, and ingestion, are retrieved and organized in the database, so the time length of each transmission phase can be figured out easily. Open source NoSQL database MongoDB is selected to manage the timestamp information because of features of dynamic schema, aggregation and data processing. A user-friendly user interface is developed to visualize and characterize the latency interactively. Taking the Himawari-8 HSD (Himawari Standard Data) file as an example, the data transmission phases, including creating HSD file from satellite observation, uploading the file to HimawariCloud, updating file link in the webpage, downloading and ingesting the file to SCDR, are worked out from the above mentioned timestamps. The latencies can be observed by time of period, day of week, or hour of day in chart or table format, and the anomaly latencies can be detected and reported through the user interface. Latency analysis provides data providers and users actionable insight on how to improve the data transmission of near real-time satellite data, and enhance its acquisition and management.

  10. Ocular HSV-1: Is the Cornea a Reservoir for Viral Latency or a Fast Pit Stop?

    Science.gov (United States)

    Kennedy, David P.; Clement, Christian; Arceneaux, Richard L.; Bhattacharjee, Partha S.; Huq, Tashfin S.; Hill, James M.

    2010-01-01

    Purpose To present a review supporting and refuting evidence from mouse, rabbit, non-human primate, and human studies of herpes simplex virus type 1 (HSV-1) concerning corneal latency. Methods More than 50 research papers on HSV-1 published in peer-reviewed journals were examined. Results Infectious HSV-1 has been found in mouse denervated tissues and in tissues with negative cultures from the corresponding ganglion. However, the different mouse strains have shown varied responses to different strains of HSV, making it difficult to relate such findings to humans. Rabbit studies provide excellent evidence for HSV-1 corneal latency including data on HSV-1 migration from the cornea into the corneoscleral rim and on the distribution of HSV-1 DNA in the cornea. However, the available methods for the detection of infectious HSV-1 may not be sensitive enough to detect low-level infection. Infectious HSV-1 has been successfully isolated from the tears of non-human primates in the absence of detectable corneal lesions. The recurrence of corneal ulcers in non-human primates before the appearance of infectious HSV-1 in tears suggests that the origin of the HSV-1 is the cornea, rather than the TG. Human studies presented evidence of both ganglion and corneal latency. Conclusion Understanding HSV-1 disease progression and the possibility of corneal latency could lead to more effective treatments for herpetic keratitis. However, it is unlikely that operational latency in the cornea will be definitively proven unless a new method with higher sensitivity for the detection of infectious virus is developed. PMID:21304287

  11. LATENCY DETERMINATION AND COMPENSATION IN REAL-TIME GNSS/INS INTEGRATED NAVIGATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    P. D. Solomon

    2012-09-01

    Full Text Available Unmanned Aerial Vehicle (UAV technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA navigation system. In practical Real-Time Navigation Systems (RTNS there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  12. Channel noise effects on first spike latency of a stochastic Hodgkin-Huxley neuron

    Science.gov (United States)

    Maisel, Brenton; Lindenberg, Katja

    2017-02-01

    While it is widely accepted that information is encoded in neurons via action potentials or spikes, it is far less understood what specific features of spiking contain encoded information. Experimental evidence has suggested that the timing of the first spike may be an energy-efficient coding mechanism that contains more neural information than subsequent spikes. Therefore, the biophysical features of neurons that underlie response latency are of considerable interest. Here we examine the effects of channel noise on the first spike latency of a Hodgkin-Huxley neuron receiving random input from many other neurons. Because the principal feature of a Hodgkin-Huxley neuron is the stochastic opening and closing of channels, the fluctuations in the number of open channels lead to fluctuations in the membrane voltage and modify the timing of the first spike. Our results show that when a neuron has a larger number of channels, (i) the occurrence of the first spike is delayed and (ii) the variation in the first spike timing is greater. We also show that the mean, median, and interquartile range of first spike latency can be accurately predicted from a simple linear regression by knowing only the number of channels in the neuron and the rate at which presynaptic neurons fire, but the standard deviation (i.e., neuronal jitter) cannot be predicted using only this information. We then compare our results to another commonly used stochastic Hodgkin-Huxley model and show that the more commonly used model overstates the first spike latency but can predict the standard deviation of first spike latencies accurately. We end by suggesting a more suitable definition for the neuronal jitter based upon our simulations and comparison of the two models.

  13. The avian fossil record in Insular Southeast Asia and its implications for avian biogeography and palaeoecology

    Directory of Open Access Journals (Sweden)

    Hanneke J.M. Meijer

    2014-03-01

    Full Text Available Excavations and studies of existing collections during the last decades have significantly increased the abundance as well as the diversity of the avian fossil record for Insular Southeast Asia. The avian fossil record covers the Eocene through the Holocene, with the majority of bird fossils Pleistocene in age. Fossil bird skeletal remains represent at least 63 species in 54 genera and 27 families, and two ichnospecies are represented by fossil footprints. Birds of prey, owls and swiftlets are common elements. Extinctions seem to have been few, suggesting continuity of avian lineages since at least the Late Pleistocene, although some shifts in species ranges have occurred in response to climatic change. Similarities between the Late Pleistocene avifaunas of Flores and Java suggest a dispersal route across southern Sundaland. Late Pleistocene assemblages of Niah Cave (Borneo and Liang Bua (Flores support the rainforest refugium hypothesis in Southeast Asia as they indicate the persistence of forest cover, at least locally, throughout the Late Pleistocene and Holocene.

  14. Status of Avian Research at the National Renewable Energy Laboratory

    International Nuclear Information System (INIS)

    Sinclair, K.

    2001-01-01

    As the use of wind energy expands across the United States, concerns about the impacts of commercial wind farms on bird and bat populations are frequently raised. Two primary areas of concern are (1) possible litigation resulting from the killing of even one bird if it is protected by the Migratory Bird Treaty Act, the Endangered Species Act, or both; and (2) the effect of avian mortality on bird populations. To properly address these concerns, the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) supports scientifically based avian/wind power interaction research. In this paper I describe NREL's field-based research projects and summarize the status of the research. I also summarize NREL's other research activities, including lab-based vision research to increase the visibility of moving turbine blades and avian acoustic research, as well as our collaborative efforts with the National Wind Coordinating Committee's Avian Subcommittee

  15. Avian Models for Human Cognitive Neuroscience: A Proposal.

    Science.gov (United States)

    Clayton, Nicola S; Emery, Nathan J

    2015-06-17

    Research on avian cognitive neuroscience over the past two decades has revealed the avian brain to be a better model for understanding human cognition than previously thought, despite differences in the neuroarchitecture of avian and mammalian brains. The brain, behavior, and cognition of songbirds have provided an excellent model of human cognition in one domain, namely learning human language and the production of speech. There are other important behavioral candidates of avian cognition, however, notably the capacity of corvids to remember the past and plan for the future, as well as their ability to think about another's perspective, and physical reasoning. We review this work and assess the evidence that the corvid brain can support such a cognitive architecture. We propose potential applications of these behavioral paradigms for cognitive neuroscience, including recent work on single-cell recordings and neuroimaging in corvids. Finally, we discuss their impact on understanding human developmental cognition. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Effects of task variables on measures of the mean onset latency of LRP depend on the scoring method.

    NARCIS (Netherlands)

    Smulders, F.T.Y.; Kenemans, J.L.; Kok, A.

    1996-01-01

    The lateralized readiness potential (LRP) can be used to index the start of response activation. The onset of the average LRP can be computed as the latency at which the component starts to deviate significantly from zero or as the latency at which a certain proportion of its maximum amplitude is

  17. Latency and bit-error-rate evaluation for radio-over-ethernet in optical fiber front-haul networks

    DEFF Research Database (Denmark)

    Sayadi, Mohammadjavad; Rodríguez, Sebastián; Olmos, Juan José Vegas

    2018-01-01

    evaluate this Ethernet packet as a case of study for RoE applications. The packet is transmitted through different fiber spans, measuring the BER and latency on each case. The system achieves BER values below the FEC limit and a manageable latency. These results serve as a guideline and proof of concept...

  18. Artist conception of the Avian Development Facility

    Science.gov (United States)

    2003-01-01

    The Avian Development Facility (ADF) supports 36 eggs in two carousels, one of which rotates to provide a 1-g control for comparing to eggs grown in microgravity. The ADF was designed to incubate up to 36 Japanese quail eggs, 18 in microgravity and 18 in artificial gravity. The two sets of eggs were exposed to otherwise identical conditions, the first time this is been accomplished in space. Eggs are preserved at intervals to provide snapshots of their development for later analysis. Quails incubate in just 15 days, so they are an ideal species to be studied within the duration of space shuttle missions. Further, several investigators can use the same specimens to address different questions. The ADF originated in NASA's Shuttle Student Involvement program in the 1980s and was developed under the NASA Small Business Irnovation Research program. In late 2001, the ADF made its first flight and carried eggs used in two investigations.

  19. Avian Influenza spread and transmission dynamics

    Science.gov (United States)

    Bourouiba, Lydia; Gourley, Stephen A.; Liu, Rongsong; Takekawa, John Y.; Wu, Jianhong; Chen, Dongmei; Moulin, Bernard; Wu, Jianhong

    2015-01-01

    The spread of highly pathogenic avian influenza (HPAI) viruses of type A of subtype H5N1 has been a serious threat to global public health. Understanding the roles of various (migratory, wild, poultry) bird species in the transmission of these viruses is critical for designing and implementing effective control and intervention measures. Developing appropriate models and mathematical techniques to understand these roles and to evaluate the effectiveness of mitigation strategies have been a challenge. Recent development of the global health surveillance (especially satellite tracking and GIS techniques) and the mathematical theory of dynamical systems combined have gradually shown the promise of some cutting-edge methodologies and techniques in mathematical biology to meet this challenge.

  20. Ontogeny of avian thermoregulation from a neural point of view

    OpenAIRE

    Baarendse, P.J.J.; Debonne, M.; Decuypere, M.P.; Kemp, B.; Brand, van den, H.

    2007-01-01

    The ontogeny of thermoregulation differs among (avian) species, but in all species both neural and endocrinological processes are involved. In this review the neural processes in ontogeny of thermoregulation during the prenatal and early postnatal phase are discussed. Only in a few avian species (chicken, ducklings) the ontogeny of some important neural structures are described. In the early post hatching phase, peripheral and deep-body thermoreceptors are present and functional, even in altr...

  1. Will Wallace's Line Save Australia from Avian Influenza?

    Directory of Open Access Journals (Sweden)

    Hamish I. McCallum

    2008-12-01

    Full Text Available Australia is separated from the Asian faunal realm by Wallace's Line, across which there is relatively little avian migration. Although this does diminish the risk of high pathogenicity avian influenza of Asian origin arriving with migratory birds, the barrier is not complete. Migratory shorebirds, as well as a few landbirds, move through the region on annual migrations to and from Southeast Asia and destinations further north, although the frequency of infection of avian influenza in these groups is low. Nonetheless, high pathogenicity H5N1 has recently been recorded on the island of New Guinea in West Papua in domestic poultry. This event increases interest in the movements of birds between Wallacea in eastern Indonesia, New Guinea, and Australia, particularly by waterbirds. There are frequent but irregular movements of ducks, geese, and other waterbirds across Torres Strait between New Guinea and Australia, including movements to regions in which H5N1 has occurred in the recent past. Although the likelihood of avian influenza entering Australia via an avian vector is presumed to be low, the nature and extent of bird movements in this region is poorly known. There have been five recorded outbreaks of high pathogenicity avian influenza in Australian poultry flocks, all of the H7 subtype. To date, Australia is the only inhabited continent not to have recorded high pathogenicity avian influenza since 1997, and H5N1 has never been recorded. The ability to map risk from high pathogenicity avian influenza to Australia is hampered by the lack of quantitative data on the extent of bird movements between Australia and its northern neighbors. Recently developed techniques offer the promise to fill this knowledge gap.

  2. Spleen necrosis virus, an avian retrovirus, can infect primate cells.

    OpenAIRE

    Koo, H M; Brown, A M; Ron, Y; Dougherty, J P

    1991-01-01

    Spleen necrosis virus (SNV) is an avian retrovirus that can infect some mammalian cells such as dog cells as well as all avian cells tested to date. We were interested in testing whether SNV could also infect primate cells. For these experiments, we used HeLa and COS-7 cells. Initially, we determined whether the SNV long terminal repeat promoter was functional in HeLa and COS-7 cells. In transient transfection assays, the SNV promoter efficiently directed chloramphenicol acetyltransferase gen...

  3. Pathogenesis of avian pneumovirus infection in turkeys.

    Science.gov (United States)

    Jirjis, F F; Noll, S L; Halvorson, D A; Nagaraja, K V; Shaw, D P

    2002-05-01

    Avian pneumovirus (APV) is the cause of a respiratory disease of turkeys characterized by coughing, ocular and nasal discharge, and swelling of the infraorbital sinuses. Sixty turkey poults were reared in isolation conditions. At 3 weeks of age, serum samples were collected and determined to be free of antibodies against APV, avian influenza, hemorrhagic enteritis, Newcastle disease, Mycoplasma gallisepticum, Mycoplasma synoviae, Mycoplasma meleagridis, Ornithobacterium rhinotracheale, and Bordetella avium. When the poults were 4 weeks old, they were inoculated with cell culture-propagated APV (APV/Minnesota/turkey/2a/97) via the conjunctival spaces and nostrils. After inoculation, four poults were euthanatized every 2 days for 14 days, and blood, swabs, and tissues were collected. Clinical signs consisting of nasal discharge, swelling of the infraorbital sinuses, and frothy ocular discharge were evident by 2 days postinoculation (PI) and persisted until day 12 PI. Mild inflammation of the mucosa of the nasal turbinates and infraorbital sinuses was present between days 2 and 10 PI. Mild inflammatory changes were seen in tracheas of poults euthanatized between days 4 and 10 PI. Antibody to APV was detected by day 7 PI. The virus was detected in tissue preparations and swabs of nasal turbinates and infraorbital sinuses by reverse transcription polymerase chain reaction, virus isolation, and immunohistochemical staining methods between days 2 and 10 PI. Virus was detected in tracheal tissue and swabs between days 2 and 6 PI using the same methods. In this experiment, turkey poults inoculated with tissue culture-propagated APV developed clinical signs similar to those seen in field cases associated with infection with this virus.

  4. Impacts of climate change on avian populations.

    Science.gov (United States)

    Jenouvrier, Stephanie

    2013-07-01

    This review focuses on the impacts of climate change on population dynamics. I introduce the MUP (Measuring, Understanding, and Predicting) approach, which provides a general framework where an enhanced understanding of climate-population processes, along with improved long-term data, are merged into coherent projections of future population responses to climate change. This approach can be applied to any species, but this review illustrates its benefit using birds as examples. Birds are one of the best-studied groups and a large number of studies have detected climate impacts on vital rates (i.e., life history traits, such as survival, maturation, or breeding, affecting changes in population size and composition) and population abundance. These studies reveal multifaceted effects of climate with direct, indirect, time-lagged, and nonlinear effects. However, few studies integrate these effects into a climate-dependent population model to understand the respective role of climate variables and their components (mean state, variability, extreme) on population dynamics. To quantify how populations cope with climate change impacts, I introduce a new universal variable: the 'population robustness to climate change.' The comparison of such robustness, along with prospective and retrospective analysis may help to identify the major climate threats and characteristics of threatened avian species. Finally, studies projecting avian population responses to future climate change predicted by IPCC-class climate models are rare. Population projections hinge on selecting a multiclimate model ensemble at the appropriate temporal and spatial scales and integrating both radiative forcing and internal variability in climate with fully specified uncertainties in both demographic and climate processes. © 2013 Blackwell Publishing Ltd.

  5. A computational feedforward model predicts categorization of masked emotional body language for longer, but not for shorter, latencies.

    Science.gov (United States)

    Stienen, Bernard M C; Schindler, Konrad; de Gelder, Beatrice

    2012-07-01

    Given the presence of massive feedback loops in brain networks, it is difficult to disentangle the contribution of feedforward and feedback processing to the recognition of visual stimuli, in this case, of emotional body expressions. The aim of the work presented in this letter is to shed light on how well feedforward processing explains rapid categorization of this important class of stimuli. By means of parametric masking, it may be possible to control the contribution of feedback activity in human participants. A close comparison is presented between human recognition performance and the performance of a computational neural model that exclusively modeled feedforward processing and was engineered to fulfill the computational requirements of recognition. Results show that the longer the stimulus onset asynchrony (SOA), the closer the performance of the human participants was to the values predicted by the model, with an optimum at an SOA of 100 ms. At short SOA latencies, human performance deteriorated, but the categorization of the emotional expressions was still above baseline. The data suggest that, although theoretically, feedback arising from inferotemporal cortex is likely to be blocked when the SOA is 100 ms, human participants still seem to rely on more local visual feedback processing to equal the model's performance.

  6. Latency modulation of collicular neurons induced by electric stimulation of the auditory cortex in Hipposideros pratti: In vivo intracellular recording.

    Directory of Open Access Journals (Sweden)

    Kang Peng

    Full Text Available In the auditory pathway, the inferior colliculus (IC receives and integrates excitatory and inhibitory inputs from the lower auditory nuclei, contralateral IC, and auditory cortex (AC, and then uploads these inputs to the thalamus and cortex. Meanwhile, the AC modulates the sound signal processing of IC neurons, including their latency (i.e., first-spike latency. Excitatory and inhibitory corticofugal projections to the IC may shorten and prolong the latency of IC neurons, respectively. However, the synaptic mechanisms underlying the corticofugal latency modulation of IC neurons remain unclear. Thus, this study probed these mechanisms via in vivo intracellular recording and acoustic and focal electric stimulation. The AC latency modulation of IC neurons is possibly mediated by pre-spike depolarization duration, pre-spike hyperpolarization duration, and spike onset time. This study suggests an effective strategy for the timing sequence determination of auditory information uploaded to the thalamus and cortex.

  7. Performance test and verification of an off-the-shelf automated avian radar tracking system.

    Science.gov (United States)

    May, Roel; Steinheim, Yngve; Kvaløy, Pål; Vang, Roald; Hanssen, Frank

    2017-08-01

    Microwave radar is an important tool for observation of birds in flight and represents a tremendous increase in observation capability in terms of amount of surveillance space that can be covered at relatively low cost. Based on off-the-shelf radar hardware, automated radar tracking systems have been developed for monitoring avian movements. However, radar used as an observation instrument in biological research has its limitations that are important to be aware of when analyzing recorded radar data. This article describes a method for exploring the detection capabilities of a dedicated short-range avian radar system used inside the operational Smøla wind-power plant. The purpose of the testing described was to find the maximum detection range for various sized birds, while controlling for the effects of flight tortuosity, flight orientation relative to the radar and ground clutter. The method was to use a dedicated test target in form of a remotely controlled unmanned aerial vehicle (UAV) with calibrated radar cross section (RCS), which enabled the design of virtually any test flight pattern within the area of interest. The UAV had a detection probability of 0.5 within a range of 2,340 m from the radar. The detection performance obtained by the RCS-calibrated test target (-11 dBm 2 , 0.08 m 2 RCS) was then extrapolated to find the corresponding performance of differently sized birds. Detection range depends on system sensitivity, the environment within which the radar is placed and the spatial distribution of birds. The avian radar under study enables continuous monitoring of bird activity within a maximum range up to 2 km dependent on the size of the birds in question. While small bird species may be detected up to 0.5-1 km, larger species may be detected up to 1.5-2 km distance from the radar.

  8. Analysis of immunoglobulin transcripts in the ostrich Struthio camelus, a primitive avian species.

    Directory of Open Access Journals (Sweden)

    Tian Huang

    Full Text Available Previous studies on the immunoglobulin (Ig genes in avian species are limited (mainly to galliformes and anseriformes but have revealed several interesting features, including the absence of the IgD and Igκ encoding genes, inversion of the IgA encoding gene and the use of gene conversion as the primary mechanism to generate an antibody repertoire. To better understand the Ig genes and their evolutionary development in birds, we analyzed the Ig genes in the ostrich (Struthio camelus, which is one of the most primitive birds. Similar to the chicken and duck, the ostrich expressed only three IgH chain isotypes (IgM, IgA and IgY and λ light chains. The IgM and IgY constant domains are similar to their counterparts described in other vertebrates. Although conventional IgM, IgA and IgY cDNAs were identified in the ostrich, we also detected a transcript encoding a short membrane-bound form of IgA (lacking the last two C(H exons that was undetectable at the protein level. No IgD or κ encoding genes were identified. The presence of a single leader peptide in the expressed heavy chain and light chain V regions indicates that gene conversion also plays a major role in the generation of antibody diversity in the ostrich. Because the ostrich is one of the most primitive living aves, this study suggests that the distinct features of the bird Ig genes appeared very early during the divergence of the avian species and are thus shared by most, if not all, avian species.

  9. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation

    Science.gov (United States)

    Kennedy, Peter G. E.; Rovnak, Joel; Badani, Hussain

    2015-01-01

    Herpes simplex virus type 1 (HSV-1; human herpesvirus 1) and varicella-zoster virus (VZV; human herpesvirus 3) are human neurotropic alphaherpesviruses that cause lifelong infections in ganglia. Following primary infection and establishment of latency, HSV-1 reactivation typically results in herpes labialis (cold sores), but can occur frequently elsewhere on the body at the site of primary infection (e.g. whitlow), particularly at the genitals. Rarely, HSV-1 reactivation can cause encephalitis; however, a third of the cases of HSV-1 encephalitis are associated with HSV-1 primary infection. Primary VZV infection causes varicella (chickenpox) following which latent virus may reactivate decades later to produce herpes zoster (shingles), as well as an increasingly recognized number of subacute, acute and chronic neurological conditions. Following primary infection, both viruses establish a latent infection in neuronal cells in human peripheral ganglia. However, the detailed mechanisms of viral latency and reactivation have yet to be unravelled. In both cases latent viral DNA exists in an ‘end-less’ state where the ends of the virus genome are joined to form structures consistent with unit length episomes and concatemers, from which viral gene transcription is restricted. In latently infected ganglia, the most abundantly detected HSV-1 RNAs are the spliced products originating from the primary latency associated transcript (LAT). This primary LAT is an 8.3 kb unstable transcript from which two stable (1.5 and 2.0 kb) introns are spliced. Transcripts mapping to 12 VZV genes have been detected in human ganglia removed at autopsy; however, it is difficult to ascribe these as transcripts present during latent infection as early-stage virus reactivation may have transpired in the post-mortem time period in the ganglia. Nonetheless, low-level transcription of VZV ORF63 has been repeatedly detected in multiple ganglia removed as close to death as possible. There is

  10. Analog Testing of Operations Concepts for Mitigation of Communication Latency During Human Space Exploration

    Science.gov (United States)

    Chappell, Steven P.; Abercromby, Andrew F.; Miller, Matthew J.; Halcon, Christopher; Gernhardt, Michael L.

    2016-01-01

    OBJECTIVES: NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. Three missions were undertaken from 2014-2015, NEEMO's 18-20. All missions were performed at the Aquarius undersea research habitat. During each mission, the effects of varying operations concepts and tasks type and complexity on representative communication latencies associated with Mars missions were studied. METHODS: 12 subjects (4 per mission) were weighed out to simulate near-zero or partial gravity extravehicular activity (EVA) and evaluated different operations concepts for integration and management of a simulated Earth-based science backroom team (SBT) to provide input and direction during exploration activities. Exploration traverses were planned in advance based on precursor data collected. Subjects completed science-related tasks including presampling surveys, geologic-based sampling, and marine-based sampling as a portion of their tasks on saturation dives up to 4 hours in duration that were to simulate extravehicular activity (EVA) on Mars or the moons of Mars. One-way communication latencies, 5 and 10 minutes between space and mission control, were simulated throughout the missions. Objective data included task completion times, total EVA times, crew idle time, translation time, SBT assimilation time (defined as time available for SBT to discuss data/imagery after it has been collected, in addition to the time taken to watch imagery streaming over latency). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. RESULTS: Precursor data can be used effectively to plan and execute exploration traverse EVAs (plans included detailed location of science sites, high-fidelity imagery of the sites, and directions to landmarks of interest within a site). Operations concepts that

  11. Economic impacts of avian influenza outbreaks in Kerala, India.

    Science.gov (United States)

    Govindaraj, G; Sridevi, R; Nandakumar, S N; Vineet, R; Rajeev, P; Binu, M K; Balamurugan, V; Rahman, H

    2018-04-01

    This study assessed the short-run impact to poultry farmers, duck hatcheries, control costs, compensation paid to stakeholders (transfer payments) and market reactions on own and substitute product prices and backwater tourism (boat operators) due to avian influenza (AI) outbreaks in Kuttanad region of Kerala, India, during 2014. The primary data from 91 poultry farms (duck farms, broiler chicken and backyard poultry), four hatcheries and 90 backwater boat owners were collected through pre-tested schedules. The secondary data on transfer payments and expenditure incurred to control AI were collected from developmental departments and were analysed. The estimated loss (culling live birds, eggs and feed destruction) per duck farm was USD 9,181, USD 3,889 and USD 156 in case of commercial farms reared for meat, dual-purpose and backyard farms, respectively. The loss incurred by small-scale broiler and backyard poultry farms was USD 453 and USD 40, respectively. The loss incurred by large and small duck hatcheries was USD 11,963 and USD 5,790, respectively, due to culling of hatchlings, young birds and destroying eggs. The government invested USD 744,890 to contain the disease spread through massive culling, surveillance and monitoring of poultry and humans due to zoonotic nature of the disease. A sharp market reaction on own and substitute product prices and eight weeks' time lag in price recovery was observed. The consequential impact on tourism especially for the backwater boat operators amounted to a loss of USD 2,280/boat due to fall in tourist inflow. Since, control measures are post-incidence, it is necessary to adopt appropriate preventive bio-security measures at the farm level besides periodical screening of domestic birds in migratory birds' flyway locations like Kuttanad to reduce the AI burden on various stakeholders including government. © 2017 Blackwell Verlag GmbH.

  12. Synergy between avian pneumovirus and Ornithobacterium rhinotracheale in turkeys.

    Science.gov (United States)

    Marien, Maja; Decostere, Annemie; Martel, An; Chiers, Koen; Froyman, Robrecht; Nauwynck, Hans

    2005-06-01

    The purpose of this study was to assess the possible synergism between Ornithobacterium rhinotracheale (ORT) and avian pneumovirus (APV), inoculated into turkeys via the natural route, for the reproduction of respiratory disease. Three-week-old specific pathogen free turkeys were inoculated oculonasally with either APV subtype A, ORT or both agents using two different time intervals (3 and 5 days) between APV and ORT. The birds were observed clinically on a daily basis and swabbed intratracheally at short, regular intervals. They were killed at 1, 3, 5, 8 and 15 days post single or dual inoculation and examined for gross lesions at necropsy. Samples of the turbinates, trachea, lungs, air sacs, heart, pericardium and liver were taken for bacteriological and/or histological examination. Combined APV/ORT infections resulted in overt clinical signs and a longer persistence of ORT in the respiratory tract and aggravated the macroscopic and histological lesions in comparison with the groups given single infections. In all ORT-challenged turkeys, ORT was isolated from the turbinates, trachea and lungs, but in turkeys infected with both agents ORT was frequently found in the air sacs and on a single occasion in the heart and pericardium. The time interval between APV and ORT inoculation did not have a significant effect on the outcome of the dual infection. A conspicuous important feature was the attachment of ORT to the cilia of the epithelium of the turbinates and trachea of both ORT-infected and APV/ORT-infected birds. In conclusion, the results show that ORT is able to adhere to and colonize the respiratory tract but, under the circumstances used in this study, is not capable of inducing respiratory disease without viral priming.

  13. Relationship between Measures of HIV Reactivation and Decline of the Latent Reservoir under Latency-Reversing Agents.

    Science.gov (United States)

    Petravic, Janka; Rasmussen, Thomas A; Lewin, Sharon R; Kent, Stephen J; Davenport, Miles P

    2017-05-01

    Antiretroviral-free HIV remission requires substantial reduction of the number of latently infected cells and enhanced immune control of viremia. Latency-reversing agents (LRAs) aim to eliminate latently infected cells by increasing the rate of reactivation of HIV transcription, which exposes these cells to killing by the immune system. As LRAs are explored in clinical trials, it becomes increasingly important to assess the effect of an increased HIV reactivation rate on the decline of latently infected cells and to estimate LRA efficacy in increasing virus reactivation. However, whether the extent of HIV reactivation is a good predictor of the rate of decline of the number of latently infected cells is dependent on a number of factors. Our modeling shows that the mechanisms of maintenance and clearance of the reservoir, the life span of cells with reactivated HIV, and other factors may significantly impact the relationship between measures of HIV reactivation and the decline in the number of latently infected cells. The usual measures of HIV reactivation are the increase in cell-associated HIV RNA (CA RNA) and/or plasma HIV RNA soon after administration. We analyze two recent studies where CA RNA was used to estimate the impact of two novel LRAs, panobinostat and romidepsin. Both drugs increased the CA RNA level 3- to 4-fold in clinical trials. However, cells with panobinostat-reactivated HIV appeared long-lived (half-life > 1 month), suggesting that the HIV reactivation rate increased by approximately 8%. With romidepsin, the life span of cells that reactivated HIV was short (2 days), suggesting that the HIV reactivation rate may have doubled under treatment. IMPORTANCE Long-lived latently infected cells that persist on antiretroviral treatment (ART) are thought to be the source of viral rebound soon after ART interruption. The elimination of latently infected cells is an important step in achieving antiretroviral-free HIV remission. Latency-reversing agents

  14. Peri-threshold encoding of stimulus frequency and intensity in the M100 latency.

    Science.gov (United States)

    Stufflebeam, S M; Poeppel, D; Rowley, H A; Roberts, T P

    1998-01-05

    Recent work has suggested that, in addition to spatial tonotopy, pitch and timbre information may be encoded in the temporal activity of the auditory cortex. Specifically, the post-stimulus latency of the maximal cortical evoked neuromagnetic field (M100 or N1m) is a function of stimulus frequency. We investigated the additional effect of varying the stimulus intensity on the M100 response. A 37-channel biomagnetometer recorded neuromagnetic fields over the temporal lobe of healthy volunteers in response to monaurally presented tones. The frequency dependence of the M100 latency remained remarkably invariant even at low stimulus intensity. Thus, for peri-threshold stimuli, frequency information appears encoded in the temporal form of the evoked response.

  15. A study of application sensitivity to variation in message passing latency and bandwidth

    Energy Technology Data Exchange (ETDEWEB)

    Worley, P.H.; Mackay, D.R. [Oak Ridge National Lab., TN (United States); Robinson, A.C. [Sandia National Labs, Albuquerque, NM (United States); Barragy, E.J. [Intel Corp., Beaverton, OR (United States)

    1996-06-01

    This study measures the effects of changes in message latency and bandwidth for production-level codes on a current generation tightly coupled MPP, the Intel Paragon. Messages are sent multiple times to study the application sensitivity to variations in band - width and latency. This method preserves the effects of contention on the interconnection network. Two applications are studied, PCTH, a shock physics code developed at Sandia National Laboratories, and PSTSWM, a spectral shallow water code developed at Oak Ridge National Laboratory and Argonne National Laboratory. These codes are significant in that PCTH is a {open_quote}full physics{close_quotes} application code in production use, while PSTSWM serves as a parallel algorithm test bed and benchmark for production codes used in atmospheric modeling. They are also significant in that the message-passing behavior differs significantly between the two codes, each representing an important class of scientific message-passing applications.

  16. Low-Latency Telerobotics from Mars Orbit: The Case for Synergy Between Science and Human Exploration

    Science.gov (United States)

    Valinia, A.; Garvin, J. B.; Vondrak, R.; Thronson, H.; Lester, D.; Schmidt, G.; Fong, T.; Wilcox, B.; Sellers, P.; White, N.

    2012-01-01

    Initial, science-directed human exploration of Mars will benefit from capabilities in which human explorers remain in orbit to control telerobotic systems on the surface (Figure 1). Low-latency, high-bandwidth telerobotics (LLT) from Mars orbit offers opportunities for what the terrestrial robotics community considers to be high-quality telepresence. Such telepresence would provide high quality sensory perception and situation awareness, and even capabilities for dexterous manipulation as required for adaptive, informed selection of scientific samples [1]. Astronauts on orbit in close communication proximity to a surface exploration site (in order to minimize communication latency) represent a capability that would extend human cognition to Mars (and potentially for other bodies such as asteroids, Venus, the Moon, etc.) without the challenges, expense, and risk of putting those humans on hazardous surfaces or within deep gravity wells. Such a strategy may be consistent with goals for a human space flight program that, are currently being developed within NASA.

  17. Reduced complexity and latency for a massive MIMO system using a parallel detection algorithm

    Directory of Open Access Journals (Sweden)

    Shoichi Higuchi

    2017-09-01

    Full Text Available In recent years, massive MIMO systems have been widely researched to realize high-speed data transmission. Since massive MIMO systems use a large number of antennas, these systems require huge complexity to detect the signal. In this paper, we propose a novel detection method for massive MIMO using parallel detection with maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD to reduce the complexity and latency. The proposed scheme obtains an R matrix after permutation of an H matrix and QR decomposition. The R matrix is also eliminated using a Gauss–Jordan elimination method. By using a modified R matrix, the proposed method can detect the transmitted signal using parallel detection. From the simulation results, the proposed scheme can achieve a reduced complexity and latency with a little degradation of the bit error rate (BER performance compared with the conventional method.

  18. Intraindividual reaction time variability affects P300 amplitude rather than latency

    Directory of Open Access Journals (Sweden)

    Anusha eRamchurn

    2014-07-01

    Full Text Available The neural correlates of intraindividual response variability were investigated in a serial choice reaction time (CRT task. Reaction times (RTs from the faster and slower portions of the RT distribution for the task were separately aggregated and associated P300 event-related potentials computed. Independent behavioral measures of executive function and IQ were also recorded. Across frontal, fronto-central, central, centro-parietal and parietal scalp regions, P300 amplitudes were significantly greater for faster relative to slower behavioral responses. However, P300 peak amplitude latencies did not differ according to the speed of the behavioral RT. Importantly, controlling for select independent measures of executive function attenuated shared variance in P300 amplitude for faster and slower trials. The findings suggest that P300 amplitude rather than latency is associated with the speed of behavioral RTs, and the possibility that fluctuations in executive control underlie variability in speeded responding.

  19. Regulation of HIV-1 latency by chromatin structure and nuclear architecture.

    Science.gov (United States)

    Lusic, Marina; Giacca, Mauro

    2015-02-13

    Current antiretroviral therapies fail to cure HIV-1 (human immunodeficiency virus type 1) infection because HIV-1 persists as a transcriptionally inactive provirus in resting memory CD4(+) T cells. Multiple molecular events are known to regulate HIV-1 gene expression, yet the mechanisms governing the establishment and maintenance of latency remain incompletely understood. Here we summarize different molecular aspects of viral latency, from its establishment in resting CD4(+) T cells to the mechanisms involved in the reactivation of latent viral reservoirs. We focus on the relevance of chromatin structure and nuclear architecture in determining the transcriptional fate of integrated HIV-1 genomes, in light of recent findings indicating that proximity to specific subnuclear neighborhoods regulates HIV-1 gene expression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Low-latency analysis pipeline for compact binary coalescences in the advanced gravitational wave detector era

    International Nuclear Information System (INIS)

    Adams, T; Buskulic, D; Germain, V; Marion, F; Mours, B; Guidi, G M; Montani, M; Piergiovanni, F; Wang, G

    2016-01-01

    The multi-band template analysis (MBTA) pipeline is a low-latency coincident analysis pipeline for the detection of gravitational waves (GWs) from compact binary coalescences. MBTA runs with a low computational cost, and can identify candidate GW events online with a sub-minute latency. The low computational running cost of MBTA also makes it useful for data quality studies. Events detected by MBTA online can be used to alert astronomical partners for electromagnetic follow-up. We outline the current status of MBTA and give details of recent pipeline upgrades and validation tests that were performed in preparation for the first advanced detector observing period. The MBTA pipeline is ready for the outset of the advanced detector era and the exciting prospects it will bring. (paper)

  1. Treatment of high-latency microcapsules containing an aluminium complex with an epoxy-functionalised trialkoxysilane.

    Science.gov (United States)

    Kamiya, Kazunobu; Suzuki, Noboru

    2016-12-01

    Some aluminium complexes are excellent catalysts of cationic polymerisation and are used for low-temperature and fast-curing adhesive, used in electronic part mounting. Microencapsulation is a suitable technique for getting high latency of the catalysts and long shelf life of the adhesives. For the higher latency in a cycloaliphatic epoxy compound, the microcapsule surface which retained small amount of aluminium complex was coated with epoxy polymer and the effect was examined. From the X-ray photoelectron spectroscopic results, the surface was recognised to be sufficiently coated and the differential scanning calorimetric analyses showed that the coating did not significantly affect the low-temperature and fast-curing properties of adhesive. After storing the mixture of cycloaliphatic epoxy compound, coated microcapsules, triphenylsilanol and silane coupling agent for 48 h at room temperature, the increase in viscosity was only 0.01 Pa s, resulting in the excellent shelf life.

  2. Research Short report

    African Journals Online (AJOL)

    Heinecken L, Vorster J, du Plessis J. Socio-economic and social capital assessment of Avian Park residents,. Worcester. Stellenbosch: Department of Sociology and Social Anthropology, Stellenbosch University, 2011. 9. Van Schalkwyk S, Bezuidenhout J, Conradie HH, et al. 'Going rural': driving change through a rural ...

  3. Noticing the self: Implicit assessment of self-focused attention using word recognition latencies

    OpenAIRE

    Eichstaedt, Dr Jan; Silvia, Dr Paul J.

    2003-01-01

    Self-focused attention is difficult to measure. Two studies developed an implicit measure of self-focus based on word recognition latencies. Self-focused attention activates self-content, so self-focused people should recognize self-relevant words more quickly. Study 1 measured individual-differences in self-focused attention. People scoring high in private self-consciousness recognized self-relevant words more quickly. Study 2 manipulated objective self-awareness with a writing task. People ...

  4. Without Latency: Cathode Immersions and the Neglected Practice of Xenocasting for Television and Radio

    OpenAIRE

    Adam Hulbert

    2015-01-01

    This paper discusses a three-year radio project Cathode Immersions, which was aired on 2SER in Sydney Australia. The audio that accompanied free-to-air television was remixed and rebroadcast in real time without latency. It explores the human and non-human aspects of the convergence of these two media, introducing ideas of xenocasting and media adjacency. The weekly xenocast of Cathode Immersions afforded unique translations of cultural narratives, from commentary on the Gulf War to machinic ...

  5. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep.

    Directory of Open Access Journals (Sweden)

    David Longbottom

    Full Text Available Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus.Three groups of sheep (groups 1, 2 and 3 were experimentally infected with different doses of C. abortus (5×10(3, 5×10(5 and 5×10(7 inclusion forming units (IFU, respectively prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b or were inoculated subcutaneously on day 70 of gestation with 2×10(6 IFU C. abortus (group 5. Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium.The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.

  6. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep.

    Science.gov (United States)

    Longbottom, David; Livingstone, Morag; Maley, Stephen; van der Zon, Arjan; Rocchi, Mara; Wilson, Kim; Wheelhouse, Nicholas; Dagleish, Mark; Aitchison, Kevin; Wattegedera, Sean; Nath, Mintu; Entrican, Gary; Buxton, David

    2013-01-01

    Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus. Three groups of sheep (groups 1, 2 and 3) were experimentally infected with different doses of C. abortus (5×10(3), 5×10(5) and 5×10(7) inclusion forming units (IFU), respectively) prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b) or were inoculated subcutaneously on day 70 of gestation with 2×10(6) IFU C. abortus (group 5). Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium. The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.

  7. The relationship of graft survival and herpes simplex virus latency in recipient corneal buttons

    OpenAIRE

    Aydemir, Orhan; Türkçüoğlu, Peykan; Bulut, Yasemin; Kalkan, Ahmet

    2007-01-01

    Orhan Aydemir1, Peykan Türkçüoglu1, Yasemin Bulut2, Ahmet Kalkan31Firat University School of Medicine, Department of Ophthalmology, Elazig, Turkey; 2Firat University School of Medicine, Department of Microbiology, Elazig, Turkey; 3Firat University School of Medicine, Department of Infectious Diseases, Elazig, TurkeyPurpose: To demonstrate relationship between herpes simplex virus (HSV) corneal latency and graft survival.Methods: Prospective case control study. 28 ...

  8. High-throughput and low-latency network communication with NetIO

    OpenAIRE

    Schumacher, Jorn; Plessl, Christian; Vandelli, Wainer

    2017-01-01

    HPC network technologies like Infiniband, TrueScale or OmniPath provide low-latency and high-throughput communication between hosts, which makes them attractive options for data-acquisition systems in large-scale high-energy physics experiments. Like HPC networks, DAQ networks are local and include a well specified number of systems. Unfortunately traditional network communication APIs for HPC clusters like MPI or PGAS target exclusively the HPC community and are not suited well for DAQ appli...

  9. IL-15 STIMULATED NATURAL KILLER CELLS CLEAR HIV-1 INFECTED CELLS FOLLOWING LATENCY REVERSAL EX VIVO.

    Science.gov (United States)

    Garrido, Carolina; Abad-Fernandez, Maria; Tuyishime, Marina; Pollara, Justin J; Ferrari, Guido; Soriano-Sarabia, Natalia; Margolis, David M

    2018-03-28

    Current efforts towards HIV eradication include approaches to augment immune recognition and elimination of persistently infected cells following latency reversal. Natural killer (NK) cells, the main effectors of the innate immune system, recognize and clear targets using different mechanisms than CD8 + T cells, offering an alternative or complementary approach for HIV clearance strategies. We assessed the impact of IL-15 treatment on NK cell function and the potential of stimulated NK cells to clear the HIV reservoir. We measured NK cell receptor expression, antibody-dependent cell-dependent cytotoxicity (ADCC), cytotoxicity, IFN-γ production and antiviral activity in autologous HIV replication systems. All NK cell functions were uniformly improved by IL-15, and more importantly, IL-15-treated NK cells were able to clear latently HIV infected cells after exposure to vorinostat, a clinically relevant latency reversing agent. We also demonstrate that NK cells from HIV infected individuals aviremic on antiretroviral therapy can be efficiently stimulated with IL-15. Our work opens a promising line of investigation towards future immunotherapies to clear persistent HIV infection using NK cells. IMPORTANCE In the search for an HIV cure, strategies to enhance immune function to allow recognition and clearance of HIV infected cells following latency reversal are being evaluated. Natural killer (NK) cells possess characteristics that can be exploited for immunotherapy against persistent HIV infection. We demonstrate that NK cells from HIV-positive donors can be strongly stimulated with IL-15, improving their antiviral and cytotoxic potential, and more importantly, clearing HIV infected cells after latency reversal with a clinically relevant drug. Our results encourage further investigation to design NK cell-based immunotherapies to achieve HIV eradication. Copyright © 2018 American Society for Microbiology.

  10. Comparison of noise-induced changes of auditory brainstem and middle latency response amplitudes in rats

    Czech Academy of Sciences Publication Activity Database

    Popelář, Jiří; Grécová, Jolana; Rybalko, Natalia; Syka, Josef

    2008-01-01

    Roč. 245, 1-2 (2008), s. 82-91 ISSN 0378-5955 R&D Projects: GA ČR GA309/07/1336; GA MZd NR8113; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : Noise exposure * Long evans rats * Middle latency responses Subject RIV: FH - Neurology Impact factor: 2.333, year: 2008

  11. The Middle Latency Response (MLR) and Steady State Evoked Potential (SSEP) in Neonates.

    Science.gov (United States)

    1985-05-01

    transplacental infections inducing pre-mature labor, low Apgar scores, neonatal asphyxia , respiratory distress syndrome, acidosis, ototoxic...TYPE OF REPORT A PERIOD COVERED The Middle Latency Response (MLR) and Steady ’YWggfl/DISSERTATION State Evoked Potential (SSEP) in Neonates :- G...Wright-Patterson AFB OH 45433 RESEARCH TITLE: The MLR and SSEP In Neonates AUTHOR: Robert C. Fifer RESEARCH ASSESSMENT QUESTIONS: 1. Did this research

  12. Pemodelan dan Verifikasi Formal Pengaruh Mobility pattern Terhadap Handoff Latency pada Jaringan WiMAX

    Directory of Open Access Journals (Sweden)

    I Nym Saputra Wahyu Wijaya

    2016-01-01

    Full Text Available In order to decrease handoff latency and increase the successful of HHO conventional scheme, a development of handover scheme is done in standard protocol WiMAX IEEE 802.16e by adding mobility pattern. The superiority of handover scheme with mobility pattern can reduce handoff latency up to 50%, mean while the weakness of this scheme is a wrong act in determining target base station are often happen. Simulation can not showing the cause of that error. So, we do formal verification in to hard handover model with mobility pattern.             In this research, behaviour system is modeled with continuous-time Markov chain (CTMC. The model is foccused to aproximating the influence of mobility pattern in to handoff latency from WiMAX hard handover mechanism. In order to set up a series markov chain models handover system can follow steps, such as: represents the state space, give a number in all transitions, generate the rate transition matrix (infinitesimal generator.             Probabilistic model checking in the research are using quantitative properties and qualitative properties. Formal verification concerning properties has relation with handover in WiMAX network showing that 70% from mobile station which doing scanning with mobility pattern are success doing handover. 24% of them doing scanning conventional as a result of wrongness in act determining target base station, so handoff latency which is pictured will bigger than a system that is only use conventional scanning method.

  13. Impact Of Latency In Wireless Networks For Real-time Multiplayer Games On Mobile Devices.

    OpenAIRE

    Vagstad, Martin Nybø; Haugsdal, Erlend Børslid

    2015-01-01

    This project describes the current state for wireless networks with regard to real-time multiplayer games on mobile devices. It looks at the limitations of these networks and mechanics to reduce the impact of the introduced network latency. The goal is to find an implementation where the user is not able to distinguish between an offline, perfect version and an online version where the user plays against other users in real time. To find this implementations the authors discuss the ch...

  14. Comparison of actigraphy immobility rules with polysomnographic sleep onset latency in children and adolescents.

    Science.gov (United States)

    Meltzer, Lisa J; Walsh, Colleen M; Peightal, Ashley A

    2015-12-01

    While actigraphy has gained popularity in pediatric sleep research, questions remain about the validity of actigraphy as an estimate of sleep-wake patterns. In particular, there is little consistency in the field in terms of scoring rules used to determine sleep onset latency. The purpose of this study was to evaluate different criteria of immobility as a measure of sleep onset latency in children and adolescents. Ninety-five youth (ages 3-17 years, 46 % male) wore both the Ambulatory Monitoring Inc. Motionlogger Sleep Watch (AMI) and the Philips Respironics Mini-Mitter Actiwatch-2 (PRMM) during overnight polysomnography in a pediatric sleep lab. We examined different sleep onset latency scoring rules (3, 5, 10, 15, and 20 min of immobility) using different algorithms (Sadeh and Cole-Kripke) and sensitivity settings (low, medium, high) for the devices. Comparisons were also made across age groups (preschoolers, school-aged, adolescents) and sleep disordered breathing status (no obstructive sleep apnea [OSA], mild OSA, clinically significant OSA). For the AMI device, shorter scoring rules performed best for children and longer scoring rules were better for adolescents, with shorter scoring rules best across sleep disordered breathing groups. For the PRMM device, medium to longer scoring rules performed best across age and sleep disordered breathing groups. Researchers are encouraged to determine the scoring rule that best fits their population of interest. Future studies are needed with larger samples of children and adolescents to further validate actigraphic immobility as a proxy for sleep onset latency.

  15. Reactivation of HIV-1 from Latency by an Ingenol Derivative from Euphorbia Kansui

    OpenAIRE

    Wang, Pengfei; Lu, Panpan; Qu, Xiying; Shen, Yinzhong; Zeng, Hanxian; Zhu, Xiaoli; Zhu, Yuqi; Li, Xian; Wu, Hao; Xu, Jianqing; Lu, Hongzhou; Ma, Zhongjun; Zhu, Huanzhang

    2017-01-01

    Cells harboring latent HIV-1 pose a major obstacle to eradication of the virus. The ?shock and kill? strategy has been broadly explored to purge the latent reservoir; however, none of the current latency-reversing agents (LRAs) can safely and effectively activate the latent virus in patients. In this study, we report an ingenol derivative called EK-16A, isolated from the traditional Chinese medicinal herb Euphorbia kansui, which displays great potential in reactivating latent HIV-1. A compari...

  16. Experiences from Implementing a Mobile Multiplayer Real-Time Game for Wireless Networks with High Latency

    Directory of Open Access Journals (Sweden)

    Alf Inge Wang

    2009-01-01

    Full Text Available This paper describes results and experiences from designing, implementing, and testing a multiplayer real-time game over mobile networks with high latency. The paper reports on network latency and bandwidth measurements from playing the game live over GPRS, EDGE, UMTS, and WLAN using the TCP and the UDP protocols. These measurements describe the practical constraints of various wireless networks and protocols when used for mobile multiplayer game purposes. Further, the paper reports on experiences from implementing various approaches to minimize issues related to high latency. Specifically, the paper focuses on a discussion about how much of the game should run locally on the client versus on the server to minimize the load on the mobile device and obtain sufficient consistency in the game. The game was designed to reveal all kinds of implementation issues of mobile network multiplayer games. The goal of the game is for a player to push other players around and into traps where they loose their lives. The game relies heavily on collision detection between the players and game objects. The paper presents experiences from experimenting with various approaches that can be used to handle such collisions, and highlights the advantages and disadvantages of the various approaches.

  17. P300 latency and amplitude in Alzheimer's disease: a systematic review.

    Science.gov (United States)

    Pedroso, Renata Valle; Fraga, Francisco J; Corazza, Danilla Icassatti; Andreatto, Carla Andrezza Almeida; Coelho, Flávia Gomes de Melo; Costa, José Luiz Riani; Santos-Galduróz, Ruth Ferreira

    2012-01-01

    The P300 plays a key role as a method for monitoring and evaluating dementia, including Alzheimer's disease. The goal of this study was to search for articles which analyzed P300 latency and amplitude values in Alzheimer's disease. We searched in the following databases: Web of Science, Pub Med, Psyc Info, Medline, Biological Abstracts and Scielo using the following keywords: speed of information processing, processing speed, information processing, aged, older, elderly, older people, alzheimer dementia, alzheimer disease, Alzheimer and cross-references of selected articles. We found eight studies matching the inclusion criteria. These studies showed that there is a consensus on a P300 latency increase of elderly patients with Alzheimer's disease compared with subjects without the disease. However, it appears that, with respect to the P300 amplitude, there is still no consensus; however, it may be related to different methodological variables adopted in the reviewed studies. There is a need to standardize the variables involved in P300 measurement for senior citizens with Alzheimer's disease in order to be able to compare P300 latency and amplitude values for this population.

  18. JPEG XS, a new standard for visually lossless low-latency lightweight image compression

    Science.gov (United States)

    Descampe, Antonin; Keinert, Joachim; Richter, Thomas; Fößel, Siegfried; Rouvroy, Gaël.

    2017-09-01

    JPEG XS is an upcoming standard from the JPEG Committee (formally known as ISO/IEC SC29 WG1). It aims to provide an interoperable visually lossless low-latency lightweight codec for a wide range of applications including mezzanine compression in broadcast and Pro-AV markets. This requires optimal support of a wide range of implementation technologies such as FPGAs, CPUs and GPUs. Targeted use cases are professional video links, IP transport, Ethernet transport, real-time video storage, video memory buffers, and omnidirectional video capture and rendering. In addition to the evaluation of the visual transparency of the selected technologies, a detailed analysis of the hardware and software complexity as well as the latency has been done to make sure that the new codec meets the requirements of the above-mentioned use cases. In particular, the end-to-end latency has been constrained to a maximum of 32 lines. Concerning the hardware complexity, neither encoder nor decoder should require more than 50% of an FPGA similar to Xilinx Artix 7 or 25% of an FPGA similar to Altera Cyclon 5. This process resulted in a coding scheme made of an optional color transform, a wavelet transform, the entropy coding of the highest magnitude level of groups of coefficients, and the raw inclusion of the truncated wavelet coefficients. This paper presents the details and status of the standardization process, a technical description of the future standard, and the latest performance evaluation results.

  19. Thermal and Cure Kinetics of Epoxy Molding Compounds Cured with Thermal Latency Accelerators

    Directory of Open Access Journals (Sweden)

    Chean-Cheng Su

    2013-01-01

    Full Text Available The cure kinetics and mechanisms of a biphenyl type epoxy molding compounds (EMCs with thermal latency organophosphine accelerators were studied using differential scanning calorimetry (DSC. Although the use of triphenylphosphine-1,4-benzoquinone (TPP-BQ and triphenylphosphine (TPP catalysts in biphenyl type EMCs exhibited autocatalytic mechanisms, thermal latency was higher in the TPP-BQ catalyst in EMCs than in the TPP catalyst in EMCs. Analyses of thermal characteristics indicated that TPP-BQ is inactive at low temperatures. At high temperatures, however, TPP-BQ increases the curing rate of EMC in dynamic and isothermal curing experiments. The reaction of EMCs with the TPP-BQ latent catalyst also had a higher temperature sensitivity compared to the reaction of EMCs with TPP catalyst. In resin transfer molding, EMCs containing the TPP-BQ thermal latency accelerator are least active at a low temperature. Consequently, EMCs have a low melt viscosity before gelation, and the resins and filler are evenly mixed in the kneading process. Additionally, flowability is increased before the EMCs form a network structure in the molding process. The proposed kinetic model adequately describes curing behavior in EMCs cured with two different organophosphine catalysts up to the rubber state in the progress of curing.

  20. Excessive daytime sleepiness in man: multiple sleep latency measurement in narcoleptic and control subjects.

    Science.gov (United States)

    Richardson, G S; Carskadon, M A; Flagg, W; Van den Hoed, J; Dement, W C; Mitler, M M

    1978-11-01

    Excessive daytime sleepiness is a complaint characterizing many disorders of the wakefulness--sleep cycle. This paper addresses the complaint of sleepiness objectively by an attempt to differentiate a group of control subjects from a group of patients with unambiguous narcolepsy. Fourteen control and 27 narcoleptic subjects were evaluated by one of three protocols involving nocturnal recordings, detailed interviews, and 5 or more 20-min opportunities to sleep offered at 2-h intervals beginning at 10.00 o'clock, +/- 30 min. Each 20-min opportunity to sleep was given to subjects lying in a darkened quiet room and asked to try to fall asleep. Polysomnographic variables were monitored and sleep was scored in 30-sec epochs by standard criteria. The interval from the start of each test to the first epoch of NREM (including stage 1 sleep) or REM sleep was called sleep latency. In two of the protocols, the subjects were awakened immediately after sleep onset. In the third protocol, the subjects were awakened after 10 min of sleep. Narcoleptics consistently fell asleep much more readily than did control subjects. We conclude that the Multiple Sleep latency test, in addition to providing opportunities to clinically document sleep onset REM sleep periods, can demonstrate pathological sleepiness. Based on these data, we suggest that an average sleep latency less than 5 min be set as the minimum cutoff point for pathological sleepiness.

  1. Compounds producing an effective combinatorial regimen for disruption of HIV-1 latency.

    Science.gov (United States)

    Hashemi, Pargol; Barreto, Kris; Bernhard, Wendy; Lomness, Adam; Honson, Nicolette; Pfeifer, Tom A; Harrigan, P Richard; Sadowski, Ivan

    2018-02-01

    Highly active antiretroviral therapy (HAART) has improved the outlook for the HIV epidemic, but does not provide a cure. The proposed "shock-and-kill" strategy is directed at inducing latent HIV reservoirs, which may then be purged via boosted immune response or targeting infected cells. We describe five novel compounds that are capable of reversing HIV latency without affecting the general T-cell activation state. The new compounds exhibit synergy for reactivation of latent provirus with other latency-reversing agents (LRAs), in particular ingenol-3-angelate/PEP005. One compound, designated PH02, was efficient at reactivating viral transcription in several cell lines bearing reporter HIV-1 at different integration sites. Furthermore, it was capable of reversing latency in resting CD4 + T lymphocytes from latently infected aviremic patient cells on HAART, while producing minimal cellular toxicity. The combination of PH02 and PEP005 produces a strong synergistic effect for reactivation, as demonstrated through a quantitative viral outgrowth assay (qVOA), on CD4 + T lymphocytes from HIV-1-infected individuals. We propose that the PH02/PEP005 combination may represent an effective novel treatment for abrogating persistent HIV-1 infection. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  2. Zebra Alphaherpesviruses (EHV-1 and EHV-9: Genetic Diversity, Latency and Co-Infections

    Directory of Open Access Journals (Sweden)

    Azza Abdelgawad

    2016-09-01

    Full Text Available Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses’ strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1 and 9 (EHV-9 have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.

  3. Modeling HIV-1 Latency in Primary T Cells Using a Replication-Competent Virus.

    Science.gov (United States)

    Martins, Laura J; Bonczkowski, Pawel; Spivak, Adam M; De Spiegelaere, Ward; Novis, Camille L; DePaula-Silva, Ana Beatriz; Malatinkova, Eva; Trypsteen, Wim; Bosque, Alberto; Vanderkerckhove, Linos; Planelles, Vicente

    2016-02-01

    HIV-1 latently infected cells in vivo can be found in extremely low frequencies. Therefore, in vitro cell culture models have been used extensively for the study of HIV-1 latency. Often, these in vitro systems utilize defective viruses. Defective viruses allow for synchronized infections and circumvent the use of antiretrovirals. In addition, replication-defective viruses cause minimal cytopathicity because they fail to spread and usually do not encode env or accessory genes. On the other hand, replication-competent viruses encode all or most viral genes and better recapitulate the nuances of the viral replication cycle. The study of latency with replication-competent viruses requires the use of antiretroviral drugs in culture, and this mirrors the use of antiretroviral treatment (ART) in vivo. We describe a model that utilizes cultured central memory CD4(+) T cells and replication-competent HIV-1. This method generates latently infected cells that can be reactivated using latency reversing agents in the presence of antiretroviral drugs. We also describe a method for the removal of productively infected cells prior to viral reactivation, which takes advantage of the downregulation of CD4 by HIV-1, and the use of a GFP-encoding virus for increased throughput.

  4. Evaluating Auditory Pathway by Electrical Auditory Middle Latency Response and Postoperative Hearing Rehabilitation.

    Science.gov (United States)

    Wang, Bin; Cao, Keli; Wei, Chaogang; Gao, Zhiqiang; Li, Huan

    2018-03-14

    To establish an effective detection method to evaluate auditory pathway in patients by electrical evoked middle latency response (EMLR) before artificial cochlear implantation, and to analyze the relationship between postoperative hearing rehabilitation and auditory cortex functions. Twenty-three patients with artificial cochlear implant were recruited. EMLR was measured after adjusting the depth of anesthesia. The electrical auditory brainstem response (EABR) mode with monopolar stimulation and two-phase alternating current square waves was selected. The parameters of EMLR waveforms were recorded by the EABR measurement system. Nerve response telemetry (NRT) was examined by measuring threshold level (T value) and comfortable level (C value) 1 month after power-on, and hearing and speech development was followed up 12 months later. The detection rate of EMLR was 95.65%. The waveforms of EMLR were comparable to those of auditory middle latency response (AMLR), showing decreased latency and interval but similar amplitude. The induction rate of NRT was 69.23%, which was much lower than that of EMLR. The EMLR thresholds were significantly correlated to the T and C values, and were comparable to the T values numerically. The Spearman's r value between EMLR waveforms and CAP scores after using the cochlear implant for 12 months was 0.673 (P auditory cortex functions and postoperative hearing rehabilitation.

  5. Targeted HIV-1 Latency Reversal Using CRISPR/Cas9-Derived Transcriptional Activator Systems.

    Directory of Open Access Journals (Sweden)

    Julia K Bialek

    Full Text Available CRISPR/Cas9 technology is currently considered the most advanced tool for targeted genome engineering. Its sequence-dependent specificity has been explored for locus-directed transcriptional modulation. Such modulation, in particular transcriptional activation, has been proposed as key approach to overcome silencing of dormant HIV provirus in latently infected cellular reservoirs. Currently available agents for provirus activation, so-called latency reversing agents (LRAs, act indirectly through cellular pathways to induce viral transcription. However, their clinical performance remains suboptimal, possibly because reservoirs have diverse cellular identities and/or proviral DNA is intractable to the induced pathways. We have explored two CRISPR/Cas9-derived activator systems as targeted approaches to induce dormant HIV-1 proviral DNA. These systems recruit multiple transcriptional activation domains to the HIV 5' long terminal repeat (LTR, for which we have identified an optimal target region within the LTR U3 sequence. Using this target region, we demonstrate transcriptional activation of proviral genomes via the synergistic activation mediator complex in various in culture model systems for HIV latency. Observed levels of induction are comparable or indeed higher than treatment with established LRAs. Importantly, activation is complete, leading to production of infective viral particles. Our data demonstrate that CRISPR/Cas9-derived technologies can be applied to counteract HIV latency and may therefore represent promising novel approaches in the quest for HIV elimination.

  6. Human Space Exploration and Human Space Flight: Latency and the Cognitive Scale of the Universe

    Science.gov (United States)

    Lester, Dan; Thronson, Harley

    2011-01-01

    The role of telerobotics in space exploration as placing human cognition on other worlds is limited almost entirely by the speed of light, and the consequent communications latency that results from large distances. This latency is the time delay between the human brain at one end, and the telerobotic effector and sensor at the other end. While telerobotics and virtual presence is a technology that is rapidly becoming more sophisticated, with strong commercial interest on the Earth, this time delay, along with the neurological timescale of a human being, quantitatively defines the cognitive horizon for any locale in space. That is, how distant can an operator be from a robot and not be significantly impacted by latency? We explore that cognitive timescale of the universe, and consider the implications for telerobotics, human space flight, and participation by larger numbers of people in space exploration. We conclude that, with advanced telepresence, sophisticated robots could be operated with high cognition throughout a lunar hemisphere by astronauts within a station at an Earth-Moon Ll or L2 venue. Likewise, complex telerobotic servicing of satellites in geosynchronous orbit can be carried out from suitable terrestrial stations.

  7. Measurement-based analysis of error latency. [in computer operating system

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1987-01-01

    This paper demonstrates a practical methodology for the study of error latency under a real workload. The method is illustrated with sampled data on the physical memory activity, gathered by hardware instrumentation on a VAX 11/780 during the normal workload cycle of the installation. These data are used to simulate fault occurrence and to reconstruct the error discovery process in the system. The technique provides a means to study the system under different workloads and for multiple days. An approach to determine the percentage of undiscovered errors is also developed and a verification of the entire methodology is performed. This study finds that the mean error latency, in the memory containing the operating system, varies by a factor of 10 to 1 (in hours) between the low and high workloads. It is found that of all errors occurring within a day, 70 percent are detected in the same day, 82 percent within the following day, and 91 percent within the third day. The increase in failure rate due to latency is not so much a function of remaining errors but is dependent on whether or not there is a latent error.

  8. Characterization of Epstein Barr virus latency pattern in Argentine breast carcinoma.

    Directory of Open Access Journals (Sweden)

    Mario A Lorenzetti

    Full Text Available INTRODUCTION: Epstein-Barr virus (EBV-associated tumors show different expression patterns of latency genes. Since in breast carcinoma this pattern is not yet fully described, our aim was to characterize EBV latency pattern in our EBV positive breast carcinoma series. METHODS: The study was conducted on 71 biopsies of breast carcinoma and in 48 non-neoplastic breast controls. EBNA1, LMP2A and LMP1 expression was assessed by immunohistochemistry with monoclonal antibodies, while viral genomic DNA and EBERs RNA transcripts expression was performed by in situ hybridization. EBV presence was confirmed by PCR. RESULTS: EBV genomic DNA and EBNA1 expression were detected in 31% (22/71 of patients specifically restricted to tumor epithelial cells in breast carcinoma while all breast control samples were negative for both viral DNA and EBNA1 protein. LMP2A was detected in 73% of EBNA1 positive cases, none of which expressed either LMP1 protein or EBERs transcripts. CONCLUSIONS: These findings suggest that EBV expression pattern in the studied biopsies could be different from those previously observed in breast carcinoma cell lines and lead us to suggest a new, EBNA1, LMP2A positive and LMP1 and EBERs negative latency profile in breast carcinoma in our population.

  9. Characterization of Epstein Barr virus latency pattern in Argentine breast carcinoma.

    Science.gov (United States)

    Lorenzetti, Mario A; De Matteo, Elena; Gass, Hugo; Martinez Vazquez, Paula; Lara, Julia; Gonzalez, Pedro; Preciado, María Victoria; Chabay, Paola A

    2010-10-22

    Epstein-Barr virus (EBV)-associated tumors show different expression patterns of latency genes. Since in breast carcinoma this pattern is not yet fully described, our aim was to characterize EBV latency pattern in our EBV positive breast carcinoma series. The study was conducted on 71 biopsies of breast carcinoma and in 48 non-neoplastic breast controls. EBNA1, LMP2A and LMP1 expression was assessed by immunohistochemistry with monoclonal antibodies, while viral genomic DNA and EBERs RNA transcripts expression was performed by in situ hybridization. EBV presence was confirmed by PCR. EBV genomic DNA and EBNA1 expression were detected in 31% (22/71) of patients specifically restricted to tumor epithelial cells in breast carcinoma while all breast control samples were negative for both viral DNA and EBNA1 protein. LMP2A was detected in 73% of EBNA1 positive cases, none of which expressed either LMP1 protein or EBERs transcripts. These findings suggest that EBV expression pattern in the studied biopsies could be different from those previously observed in breast carcinoma cell lines and lead us to suggest a new, EBNA1, LMP2A positive and LMP1 and EBERs negative latency profile in breast carcinoma in our population.

  10. Low-Latency Teleoperations for Human Exploration and Evolvable Mars Campaign

    Science.gov (United States)

    Lupisella, Mark; Wright, Michael; Arney, Dale; Gershman, Bob; Stillwagen, Fred; Bobskill, Marianne; Johnson, James; Shyface, Hilary; Larman, Kevin; Lewis, Ruthan; hide

    2015-01-01

    NASA has been analyzing a number of mission concepts and activities that involve low-latency telerobotic (LLT) operations. One mission concept that will be covered in this presentation is Crew-Assisted Sample Return which involves the crew acquiring samples (1) that have already been delivered to space, and or acquiring samples via LLT from orbit to a planetary surface and then launching the samples to space to be captured in space and then returned to the earth with the crew. Both versions of have key roles for low-latency teleoperations. More broadly, the NASA Evolvable Mars Campaign is exploring a number of other activities that involve LLT, such as: (a) human asteroid missions, (b) PhobosDeimos missions, (c) Mars human landing site reconnaissance and site preparation, and (d) Mars sample handling and analysis. Many of these activities could be conducted from Mars orbit and also with the crew on the Mars surface remotely operating assets elsewhere on the surface, e.g. for exploring Mars special regions and or teleoperating a sample analysis laboratory both of which may help address planetary protection concerns. The operational and technology implications of low-latency teleoperations will be explored, including discussion of relevant items in the NASA Technology Roadmap and also how previously deployed robotic assets from any source could subsequently be used by astronauts via LLT.

  11. Latency requirements for head-worn display S/EVS applications

    Science.gov (United States)

    Bailey, Randall E.; Arthur, Jarvis J., III; Williams, Steven P.

    2004-08-01

    NASA's Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas - flight control, flight simulation, and virtual reality - are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

  12. Exploring novel candidate genes from the Mouse Genome Informatics database: Potential implications for avian migration research.

    Science.gov (United States)

    Contina, Andrea; Bridge, Eli S; Kelly, Jeffrey F

    2016-07-01

    To search for genes associated with migratory phenotypes in songbirds, we selected candidate genes through annotations from the Mouse Genome Informatics database and assembled an extensive candidate-gene library. Then, we implemented a next-generation sequencing approach to obtain DNA sequences from the Painted Bunting genome. We focused on those sequences that were conserved across avian species and that aligned with candidate genes in our mouse library. We genotyped short sequence repeats from the following candidate genes: ADRA1d, ANKRD17, CISH and MYH7. We studied the possible correlations between allelic variations occurring in these novel candidate migration genes and avian migratory phenotypes available from the published literature. We found that allele variation at MYH7 correlated with a calculated index of speed of migration (km/day) across 11 species of songbirds. We highlight the potential of the Mouse Genome Informatics database in providing new candidate genes that might play a crucial role in regulating migration in birds and possibly in other taxa. Our research effort shows the benefits and limitations of working with extensive genomic datasets and offers a snapshot of the challenges related to cross-species validation in behavioral and molecular ecology studies. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  13. Endogenous avian leukosis viral loci in the Red Jungle Fowl genome assembly.

    Science.gov (United States)

    Benkel, Bernhard; Rutherford, Katherine

    2014-12-01

    The current build (galGal4) of the genome of the ancestor of the modern chicken, the Red Jungle Fowl, contains a single endogenous avian leukosis viral element (ALVE) on chromosome 1 (designated RSV-LTR; family ERVK). The assembly shows the ALVE provirus juxtaposed with a member of a second family of avian endogenous retroviruses (designated GGERV20; family ERVL); however, the status of the 3' end of the ALVE element as well as its flanking region remain unclear due to a gap in the reference genome sequence. In this study, we filled the gap in the assembly using a combination of long-range PCR (LR-PCR) and a short contig present in the unassembled portion of the reference genome database. Our results demonstrate that the ALVE element (ALVE-JFevB) is inserted into the putative envelope region of a GGERV20 element, roughly 1 kbp from its 3' end, and that ALVE-JFevB is complete, and depending on its expression status, potentially capable of directing the production of virus. Moreover, the unassembled portion of the genome database contains junction fragments for a second, previously characterized endogenous proviral element, ALVE-6. ©2014 Poultry Science Association Inc.

  14. Expression of Immune-Related Genes of Ducks Infected with Avian Pathogenic Escherichia coli (APEC

    Directory of Open Access Journals (Sweden)

    Rong eLi

    2016-05-01

    Full Text Available Avian pathogenic Escherichia coli (APEC can cause severe disease in ducks, characterized by perihepatitis, pericarditis and airsacculitis. Although the studies of bacteria isolation and methods of detection have been reported, host immune responses to APEC infection remain unclear. In response, we systemically examined the expression of immune-related genes and bacteria distribution in APEC-infected ducks. Results demonstrated that APEC can quickly replicate in the liver, spleen and brain, with the highest bacteria content at 2 day post infection. The expression of Toll-like receptors (TLRs, avian β-defensins (AvBDs and major histocompatibility complex (MHC were tested in the liver, spleen and brain of infected ducks. TLR2, TLR4, TLR5 and TLR15 showed different expression patterns, which indicated that they all responded to APEC infection. The expression of AvBD2 was upregulated in all tested tissues during the 3 days of testing, whereas the expression of AvBD4, AvBD5, AvBD7 and AvBD9 were downregulated, and though MHC-I was upregulated on all test days, MHC-II was dramatically downregulated. Overall, our results suggest that APEC can replicate in various tissues in a short time, and the activation of host immune responses begins at onset of infection. These findings thus clarify duck immune responses to APEC infection and offer insights into its pathogenesis.

  15. The Wnt Signaling Pathway Is Differentially Expressed during the Bovine Herpesvirus 1 Latency-Reactivation Cycle: Evidence That Two Protein Kinases Associated with Neuronal Survival, Akt3 and BMPR2, Are Expressed at Higher Levels during Latency.

    Science.gov (United States)

    Workman, Aspen; Zhu, Liqian; Keel, Brittney N; Smith, Timothy P L; Jones, Clinton

    2018-04-01

    Sensory neurons in trigeminal ganglia (TG) of calves latently infected with bovine herpesvirus 1 (BoHV-1) abundantly express latency-related (LR) gene products, including a protein (ORF2) and two micro-RNAs. Recent studies in mouse neuroblastoma cells (Neuro-2A) demonstrated ORF2 interacts with β-catenin and a β-catenin coactivator, high-mobility group AT-hook 1 (HMGA1) protein, which correlates with increased β-catenin-dependent transcription and cell survival. β-Catenin and HMGA1 are readily detected in a subset of latently infected TG neurons but not TG neurons from uninfected calves or reactivation from latency. Consequently, we hypothesized that the Wnt/β-catenin signaling pathway is differentially expressed during the latency and reactivation cycle and an active Wnt pathway promotes latency. RNA-sequencing studies revealed that 102 genes associated with the Wnt/β-catenin signaling pathway were differentially expressed in TG during the latency-reactivation cycle in calves. Wnt agonists were generally expressed at higher levels during latency, but these levels decreased during dexamethasone-induced reactivation. The Wnt agonist bone morphogenetic protein receptor 2 (BMPR2) was intriguing because it encodes a serine/threonine receptor kinase that promotes neuronal differentiation and inhibits cell death. Another differentially expressed gene encodes a protein kinase (Akt3), which is significant because Akt activity enhances cell survival and is linked to herpes simplex virus 1 latency and neuronal survival. Additional studies demonstrated ORF2 increased Akt3 steady-state protein levels and interacted with Akt3 in transfected Neuro-2A cells, which correlated with Akt3 activation. Conversely, expression of Wnt antagonists increased during reactivation from latency. Collectively, these studies suggest Wnt signaling cooperates with LR gene products, in particular ORF2, to promote latency. IMPORTANCE Lifelong BoHV-1 latency primarily occurs in sensory neurons

  16. Avian vocal mimicry: a unified conceptual framework.

    Science.gov (United States)

    Dalziell, Anastasia H; Welbergen, Justin A; Igic, Branislav; Magrath, Robert D

    2015-05-01

    Mimicry is a classical example of adaptive signal design. Here, we review the current state of research into vocal mimicry in birds. Avian vocal mimicry is a conspicuous and often spectacular form of animal communication, occurring in many distantly related species. However, the proximate and ultimate causes of vocal mimicry are poorly understood. In the first part of this review, we argue that progress has been impeded by conceptual confusion over what constitutes vocal mimicry. We propose a modified version of Vane-Wright's (1980) widely used definition of mimicry. According to our definition, a vocalisation is mimetic if the behaviour of the receiver changes after perceiving the acoustic resemblance between the mimic and the model, and the behavioural change confers a selective advantage on the mimic. Mimicry is therefore specifically a functional concept where the resemblance between heterospecific sounds is a target of selection. It is distinct from other forms of vocal resemblance including those that are the result of chance or common ancestry, and those that have emerged as a by-product of other processes such as ecological convergence and selection for large song-type repertoires. Thus, our definition provides a general and functionally coherent framework for determining what constitutes vocal mimicry, and takes account of the diversity of vocalisations that incorporate heterospecific sounds. In the second part we assess and revise hypotheses for the evolution of avian vocal mimicry in the light of our new definition. Most of the current evidence is anecdotal, but the diverse contexts and acoustic structures of putative vocal mimicry suggest that mimicry has multiple functions across and within species. There is strong experimental evidence that vocal mimicry can be deceptive, and can facilitate parasitic interactions. There is also increasing support for the use of vocal mimicry in predator defence, although the mechanisms are unclear. Less progress has

  17. Antimicrobial Products Registered for Disinfection Use against Avian Influenza on Poultry Farms and Other Facilities

    Science.gov (United States)

    EPA registers disinfectants against Avian Influenza A. Although there are no antimicrobial products registered for the H5N2 subtype of Avian Influenza A virus, based on available scientific information these products will work against other HPAI strains.

  18. Auditory-Cortex Short-Term Plasticity Induced by Selective Attention

    Science.gov (United States)

    Jääskeläinen, Iiro P.; Ahveninen, Jyrki

    2014-01-01

    The ability to concentrate on relevant sounds in the acoustic environment is crucial for everyday function and communication. Converging lines of evidence suggests that transient functional changes in auditory-cortex neurons, “short-term plasticity”, might explain this fundamental function. Under conditions of strongly focused attention, enhanced processing of attended sounds can take place at very early latencies (~50 ms from sound onset) in primary auditory cortex and possibly even at earlier latencies in subcortical structures. More robust selective-attention short-term plasticity is manifested as modulation of responses peaking at ~100 ms from sound onset in functionally specialized nonprimary auditory-cortical areas by way of stimulus-specific reshaping of neuronal receptive fields that supports filtering of selectively attended sound features from task-irrelevant ones. Such effects have been shown to take effect in ~seconds following shifting of attentional focus. There are findings suggesting that the reshaping of neuronal receptive fields is even stronger at longer auditory-cortex response latencies (~300 ms from sound onset). These longer-latency short-term plasticity effects seem to build up more gradually, within tens of seconds after shifting the focus of attention. Importantly, some of the auditory-cortical short-term plasticity effects observed during selective attention predict enhancements in behaviorally measured sound discrimination performance. PMID:24551458

  19. [Decrease in N170 evoked potential component latency during repeated presentation of face images].

    Science.gov (United States)

    Verkhliutov, V M; Ushakov, V L; Strelets, V B

    2009-01-01

    The 15 healthy volunteers EEG from 28 channels was recorded during the presentation of visual stimuli in the form of face and building images. The stimuli were presented in two series. The first series consisted of 60 face and 60 building images presented in random order. The second series consisted of 30 face and 30 building images. The second series began 1.5-2 min after the end of the first ore. No instruction was given to the participants. P1, N170 and VPP EP components were identified for both stimuli categories. These components were located in the medial parietal area (Brodmann area 40). P1 and N170 components were recorded in the superior temporal fissure (Brodmann area 21, STS region), the first component had the latency 120 ms, the second one--155 ms. VPP was recorded with the latency 190 ms (Brodmann area 19). Dynamic mapping of EP components with the latency from 97 to 242 ms revealed the removal of positive maximums from occipital to frontal areas through temporal ones and their subsequent returning to occipital areas through the central ones. During the comparison of EP components to face and building images the amplitude differences were revealed in the following areas: P1--in frontal, central and anterior temporal areas, N170--in frontal, central, temporal and parietal areas, VPP--in all areas. It was also revealed that N170 latency was 12 ms shorter for face than for building images. It was proposed that the above mentioned N170 latency decrease for face in comparison with building images is connected with the different space location of the fusiform area responsible for face and building images recognition. Priming--the effect that is revealed during the repetitive face images presentation is interpreted as the manifestation of functional heterogeneity of the fusiform area responsible for the face images recognition. The hypothesis is put forward that the parts of extrastriate cortex which are located closer to the central retinotopical

  20. NEEMO 18-20: Analog Testing for Mitigation of Communication Latency During Human Space Exploration

    Science.gov (United States)

    Chappell, Steven P.; Beaton, Kara H.; Miller, Matthew J.; Graff, Trevor G.; Abercromby, Andrew F. J.; Gernhardt, Michael L.; Halcon, Christopher

    2016-01-01

    NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. Three missions were undertaken from 2014-2015, NEEMO's 18-20. All missions were performed at the Aquarius undersea research habitat. During each mission, the effects of communication latencies on operations concepts, timelines, and tasks were studied. METHODS: Twelve subjects (4 per mission) were weighed out to simulate near-zero or partial gravity extravehicular activity (EVA) and evaluated different operations concepts for integration and management of a simulated Earth-based science team (ST) to provide input and direction during exploration activities. Exploration traverses were preplanned based on precursor data. Subjects completed science-related tasks including pre-sampling surveys, geologic-based sampling, and marine-based sampling as a portion of their tasks on saturation dives up to 4 hours in duration that were designed to simulate extravehicular activity (EVA) on Mars or the moons of Mars. One-way communication latencies, 5 and 10 minutes between space and mission control, were simulated throughout the missions. Objective data included task completion times, total EVA times, crew idle time, translation time, ST assimilation time (defined as time available for ST to discuss data/imagery after data acquisition). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. RESULTS: Precursor data can be used effectively to plan and execute exploration traverse EVAs (plans included detailed location of science sites, high-fidelity imagery of the sites, and directions to landmarks of interest within a site). Operations concepts that allow for pre-sampling surveys enable efficient traverse execution and meaningful Mission Control Center (MCC) interaction across communication latencies and can be

  1. Quantifying risk over the life course - latency, age-related susceptibility, and other time-varying exposure metrics.

    Science.gov (United States)

    Wang, Molin; Liao, Xiaomei; Laden, Francine; Spiegelman, Donna

    2016-06-15

    Identification of the latency period and age-related susceptibility, if any, is an important aspect of assessing risks of environmental, nutritional, and occupational exposures. We consider estimation and inference for latency and age-related susceptibility in relative risk and excess risk models. We focus on likelihood-based methods for point and interval estimation of the latency period and age-related windows of susceptibility coupled with several commonly considered exposure metrics. The method is illustrated in a study of the timing of the effects of constituents of air pollution on mortality in the Nurses' Health Study. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Community response to avian flu in Central Java, Indonesia.

    Science.gov (United States)

    Padmawati, Siwi; Nichter, Mark

    2008-04-01

    This pilot study suggests that it is more appropriate to think of avian flu as a bio-social and bio-political challenge for Indonesia than merely an epidemiological challenge involving a disease of zoonotic origin. Our examination of popular perceptions of avian flu in Central Java reveals important differences of opinion about which types of fowl are responsible for avian flu transmission and the degree of risk H5N1 poses to humans. The opinions of backyard farmers and commercial poultry farmers are motivated by different forms of practical logic and are differentially influenced by media accounts, government education programmes, foreign aid and rumours about who stands to profit from the disease. Rumours reflect collective anxieties about globalization, the agenda of big business and the trustworthiness of the national government. We also illustrate how a commodity chain analysis can assist in the identification of different stake-holders in the informal and formal poultry industries. The position of each stake-holder needs to be considered in any comprehensive investigation of avian flu. An economic analysis of the capital investment of stake-holders provides insight into how each responds to government directives about the reporting of dead chickens, vaccinating birds etc. Finally, we call for research on avian flu preparedness attentive to Indonesia's de-centralized form of political rule and the social organization of communities so that clear lines of communication and command can be established and mutual assistance mobilized.

  3. Persistence of Pasteurella multocida in wetlands following avian cholera outbreaks

    Science.gov (United States)

    Blanchong, Julie A.; Samuel, M.D.; Goldberg, Diana R.; Shadduck, D.J.; Lehr, M.A.

    2006-01-01

    Avian cholera, caused by Pasteurella multocida, affects waterbirds across North America and occurs worldwide among various avian species. Once an epizootic begins, contamination of the wetland environment likely facilitates the transmission of P. multocida to susceptible birds. To evaluate the ability of P. multocida serotype-1, the most common serotype associated with avian cholera in waterfowl in western and central North America, to persist in wetlands and to identify environmental factors associated with its persistence, we collected water and sediment samples from 23 wetlands during winters and springs of 1996a??99. These samples were collected during avian cholera outbreaks and for up to 13 wk following initial sampling. We recovered P. multocida from six wetlands that were sampled following the initial outbreaks, but no P. multocida was isolated later than 7 wk after the initial outbreak sampling. We found no significant relationship between the probability of recovery of P. multocida during resampling and the abundance of the bacterium recovered during initial sampling, the substrate from which isolates were collected, isolate virulence, or water quality conditions previously suggested to be related to the abundance or survival of P. multocida. Our results indicate that wetlands are unlikely to serve as a long-term reservoir for P. multocida because the bacterium does not persist in wetlands for long time periods following avian cholera outbreaks.

  4. Detecting emerging transmissibility of avian influenza virus in human households.

    Directory of Open Access Journals (Sweden)

    Michiel van Boven

    2007-07-01

    Full Text Available Accumulating infections of highly pathogenic H5N1 avian influenza in humans underlines the need to track the ability of these viruses to spread among humans. A human-transmissible avian influenza virus is expected to cause clusters of infections in humans living in close contact. Therefore, epidemiological analysis of infection clusters in human households is of key importance. Infection clusters may arise from transmission events from (i the animal reservoir, (ii humans who were infected by animals (primary human-to-human transmission, or (iii humans who were infected by humans (secondary human-to-human transmission. Here we propose a method of analysing household infection data to detect changes in the transmissibility of avian influenza viruses in humans at an early stage. The method is applied to an outbreak of H7N7 avian influenza virus in The Netherlands that was the cause of more than 30 human-to-human transmission events. The analyses indicate that secondary human-to-human transmission is plausible for the Dutch household infection data. Based on the estimates of the within-household transmission parameters, we evaluate the effectiveness of antiviral prophylaxis, and conclude that it is unlikely that all household infections can be prevented with current antiviral drugs. We discuss the applicability of our method for the detection of emerging human-to-human transmission of avian influenza viruses in particular, and for the analysis of within-household infection data in general.

  5. Next generation sequencing technologies: tool to study avian virus diversity.

    Science.gov (United States)

    Kapgate, S S; Barbuddhe, S B; Kumanan, K

    2015-03-01

    Increased globalisation, climatic changes and wildlife-livestock interface led to emergence of novel viral pathogens or zoonoses that have become serious concern to avian, animal and human health. High biodiversity and bird migration facilitate spread of the pathogen and provide reservoirs for emerging infectious diseases. Current classical diagnostic methods designed to be virus-specific or aim to be limited to group of viral agents, hinder identifying of novel viruses or viral variants. Recently developed approaches of next-generation sequencing (NGS) provide culture-independent methods that are useful for understanding viral diversity and discovery of novel virus, thereby enabling a better diagnosis and disease control. This review discusses the different possible steps of a NGS study utilizing sequence-independent amplification, high-throughput sequencing and bioinformatics approaches to identify novel avian viruses and their diversity. NGS lead to the identification of a wide range of new viruses such as picobirnavirus, picornavirus, orthoreovirus and avian gamma coronavirus associated with fulminating disease in guinea fowl and is also used in describing viral diversity among avian species. The review also briefly discusses areas of viral-host interaction and disease associated causalities with newly identified avian viruses.

  6. An Outbreak Of Highly Pathogenic Avian Influenza (Hpai) In A Mixed ...

    African Journals Online (AJOL)

    An Outbreak Of Highly Pathogenic Avian Influenza (Hpai) In A Mixed Farm By The Introduction Of A Water Fowl. ... C A Meseko, A T Oladokun, B Shehu. Abstract. Avian influenza (AI) is caused by a range of Influenza type A viruses of high and low pathogenicity (Fauci, 2005). H5N1 Highly Pathogenic Avian Influenza (HPAI) ...

  7. The influence of vertical and horizontal habitat structure on nationwide patterns of avian biodiversity

    Science.gov (United States)

    Patrick D. Culbert; Volker C. Radeloff; Curtis H. Flather; Josef M. Kellndorfer; Chadwick D. Rittenhouse; Anna M. Pidgeon

    2013-01-01

    With limited resources for habitat conservation, the accurate identification of high-value avian habitat is crucial. Habitat structure affects avian biodiversity but is difficult to quantify over broad extents. Our goal was to identify which measures of vertical and horizontal habitat structure are most strongly related to patterns of avian biodiversity across the...

  8. 9 CFR 145.15 - Diagnostic surveillance program for low pathogenic avian influenza.

    Science.gov (United States)

    2010-01-01

    ... low pathogenic avian influenza. 145.15 Section 145.15 Animals and Animal Products ANIMAL AND PLANT... pathogenic avian influenza. (a) The Official State Agency must develop a diagnostic surveillance program for H5/H7 low pathogenic avian influenza for all poultry in the State. The exact provisions of the...

  9. Experimental induced avian E. coli salpingitis

    DEFF Research Database (Denmark)

    Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth

    2016-01-01

    Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease manifesta......Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease...... manifestations or from the cloacae of a healthy chicken. The virulence potential of the strains were evaluated in an avian experimental model for ascending infections, and experiments were conducted in both layers and broiler breeders. The clinical outcome of infection was highly depending on the challenge......) had a distinct ability to cause disease. Results of the study shows major differences in virulence of different strains of E. coli in ascending infections; however, there was no indication of tissue-specific adaptation, since strains obtained from lesions unrelated to the reproductive system were...

  10. Avian endocrine responses to environmental pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Rattner, B.A.; Eroschenko, V.P.; Fox, G.A.; Fry, D.M.; Gorsline, J.

    1984-12-01

    Many environmental contaminants are hazardous to populations of wild birds. Chlorinated hydrocarbon pesticides and industrial pollutants are thought to be responsible for population declines of several species of predatory birds through eggshell thinning. Studies have demonstrated that these contaminants have estrogenic potency and may affect the functioning of the gonadal and thyroidal endocrine subsystems. Petroleum crude oil exerts toxicity externally, by oiling of plumage, and internally, by way of ingestion of oil while feeding or preening. Extensive ultrastructural damage to the inner zone of the adrenal, diminished adrenal responsiveness to adrenocorticotrophic hormone, and reduced corticosterone secretion rate suggest that low levels of plasma corticosterone reflect a direct effect of petroleum on the adrenal gland. Suppressive effects of oil on the ovary and decreases in circulating prolactin have been associated with impaired reproductive function. Large-scale field studies of free-living seabirds have confirmed some of the inhibitory effects of oil on reproduction that have been observed in laboratory studies. Organophosphorus insecticides, representing the most widely used class of pesticides in North America, have been shown to impair reproductive function, possibly by altering secretion of luteinizing hormone and progesterone. Relevant areas of future research on the effects of contaminants on avian endocrine function are discussed.

  11. Comparison of lead residues among avian bones

    International Nuclear Information System (INIS)

    Ethier, A.L.M.; Braune, B.M.; Scheuhammer, A.M.; Bond, D.E.

    2007-01-01

    To determine if significant differences exist in lead (Pb) accumulation in different bones, especially those most often used for bone-Pb studies in wildlife, we compared Pb concentrations in radius, ulna, humerus, femur, and tibia of Common Eider (Somateria mollissima); and radius/ulna (combined), femur, and tibia of American Woodcock (Scolopax minor). There were no significant differences in bone-Pb concentrations among woodcock bones over a wide range of Pb concentrations (3-311 μg/g). In eider, where bone-Pb concentrations were low (<10 μg/g), leg bones had significantly higher Pb concentrations (approximately 30-40%) than wing bones from the same individuals. The variation among individual birds was greater than the variation among different bones within a bird. Based on our findings, we conclude that one type of bone may be substituted for another in bone-Pb studies although the same bone type should be analyzed for all birds within a study, whenever possible. - Variability in Pb concentrations among avian bones

  12. Public health risk from avian influenza viruses.

    Science.gov (United States)

    Perdue, Michael L; Swayne, David E

    2005-09-01

    Since 1997, avian influenza (AI) virus infections in poultry have taken on new significance, with increasing numbers of cases involving bird-to-human transmission and the resulting production of clinically severe and fatal human infections. Such human infections have been sporadic and are caused by H7N7 and H5N1 high-pathogenicity (HP) and H9N2 low-pathogenicity (LP) AI viruses in Europe and Asia. These infections have raised the level of concern by human health agencies for the potential reassortment of influenza virus genes and generation of the next human pandemic influenza A virus. The presence of endemic infections by H5N1 HPAI viruses in poultry in several Asian countries indicates that these viruses will continue to contaminate the environment and be an exposure risk with human transmission and infection. Furthermore, the reports of mammalian infections with H5N1 AI viruses and, in particular, mammal-to-mammal transmission in humans and tigers are unprecedented. However, the subsequent risk for generating a pandemic human strain is unknown. More international funding from both human and animal health agencies for diagnosis or detection and control of AI in Asia is needed. Additional funding for research is needed to understand why and how these AI viruses infect humans and what pandemic risks they pose.

  13. Avian Metapneumovirus circulation in Italian broiler farms.

    Science.gov (United States)

    Tucciarone, Claudia Maria; Franzo, Giovanni; Lupini, Caterina; Alejo, Carolina Torres; Listorti, Valeria; Mescolini, Giulia; Brandão, Paulo Eduardo; Martini, Marco; Catelli, Elena; Cecchinato, Mattia

    2018-02-01

    With increasing frequency, avian Metapneumovirus (aMPV) is reported to induce respiratory signs in chickens. An adequate knowledge of current aMPV prevalence among Italian broilers is lacking, with little information available on its economical and health impact on the poultry industry. In order to collect preliminary data on the epidemiological context of aMPV in broiler flocks, a survey was performed in areas of Northern Italy with high poultry density from 2014 to 2016. Upper respiratory tract swabs were collected and processed by A and B subtype-specific multiplex real-time reverse transcription PCR (RT-PCR). Samples were also screened for infectious bronchitis virus (IBV) by generic RT-PCR and sequencing. Productive data and respiratory signs were detailed where possible. The high prevalence of aMPV was confirmed in broilers older than 26 d and also attested in IBV-negative farms. All aMPV detections belonged to subtype B. Italian strain genetic variability was evaluated by the partial attachment (G) gene sequencing of selected strains and compared with contemporary turkey strains and previously published aMPV references, revealing no host specificity and the progressive evolution of this virus in Italy. © 2017 Poultry Science Association Inc.

  14. Worldwide phylogenetic relationship of avian poxviruses

    Science.gov (United States)

    Gyuranecz, Miklós; Foster, Jeffrey T.; Dán, Ádám; Ip, Hon S.; Egstad, Kristina F.; Parker, Patricia G.; Higashiguchi, Jenni M.; Skinner, Michael A.; Höfle, Ursula; Kreizinger, Zsuzsa; Dorrestein, Gerry M.; Solt, Szabolcs; Sós, Endre; Kim, Young Jun; Uhart, Marcela; Pereda, Ariel; González-Hein, Gisela; Hidalgo, Hector; Blanco, Juan-Manuel; Erdélyi, Károly

    2013-01-01

    Poxvirus infections have been found in 230 species of wild and domestic birds worldwide in both terrestrial and marine environments. This ubiquity raises the question of how infection has been transmitted and globally dispersed. We present a comprehensive global phylogeny of 111 novel poxvirus isolates in addition to all available sequences from GenBank. Phylogenetic analysis of Avipoxvirus genus has traditionally relied on one gene region (4b core protein). In this study we have expanded the analyses to include a second locus (DNA polymerase gene), allowing for a more robust phylogenetic framework, finer genetic resolution within specific groups and the detection of potential recombination. Our phylogenetic results reveal several major features of avipoxvirus evolution and ecology and propose an updated avipoxvirus taxonomy, including three novel subclades. The characterization of poxviruses from 57 species of birds in this study extends the current knowledge of their host range and provides the first evidence of the phylogenetic effect of genetic recombination of avipoxviruses. The repeated occurrence of avian family or order-specific grouping within certain clades (e.g. starling poxvirus, falcon poxvirus, raptor poxvirus, etc.) indicates a marked role of host adaptation, while the sharing of poxvirus species within prey-predator systems emphasizes the capacity for cross-species infection and limited host adaptation. Our study provides a broad and comprehensive phylogenetic analysis of the Avipoxvirus genus, an ecologically and environmentally important viral group, to formulate a genome sequencing strategy that will clarify avipoxvirus taxonomy.

  15. Effects of task variables on measures of the mean onset latency of LRP depend on the scoring method.

    Science.gov (United States)

    Smulders, F T; Kenemans, J L; Kok, A

    1996-03-01

    The lateralized readiness potential (LRP) can be used to index the start of response activation. The onset of the average LRP can be computed as the latency at which the component starts to deviate significantly from zero or as the latency at which a certain proportion of its maximum amplitude is attained. The properties of both measures as estimates of the mean onset latency of the LRP were examined. Experiment 1 was a simulation study in which the mean onset latencies were known. Results indicated different types of bias for the two measures and greater reliability for a proportional measure. In Experiment 2, the sensitivity to bias, consistency, and linearity of both measures were evaluated in a set of empirical data. By all three criteria, a proportional onset measure was superior. It is recommended that the choice of the measure should depend on the hypothesis to be tested, so that conclusions are based on the more conservative test.

  16. Outcomes of a NASA Workshop to Develop a Portfolio of Low Latency Datasets for Time-Sensitive Applications

    Science.gov (United States)

    Davies, Diane K.; Brown, Molly E.; Green, David S.; Michael, Karen A.; Murray, John J.; Justice, Christopher O.; Soja, Amber J.

    2016-01-01

    It is widely accepted that time-sensitive remote sensing data serve the needs of decision makers in the applications communities and yet to date, a comprehensive portfolio of NASA low latency datasets has not been available. This paper will describe the NASA low latency, or Near-Real Time (NRT), portfolio, how it was developed and plans to make it available online through a portal that leverages the existing EOSDIS capabilities such as the Earthdata Search Client (https:search.earthdata.nasa.gov), the Common Metadata Repository (CMR) and the Global Imagery Browse Service (GIBS). This paper will report on the outcomes of a NASA Workshop to Develop a Portfolio of Low Latency Datasets for Time-Sensitive Applications (27-29 September 2016 at NASA Langley Research Center, Hampton VA). The paper will also summarize findings and recommendations from the meeting outlining perceived shortfalls and opportunities for low latency research and application science.

  17. Effect of magnesium sulfate administration for neuroprotection on latency in women with preterm premature rupture of membranes.

    LENUS (Irish Health Repository)

    Horton, Amanda L

    2015-03-01

    This study aims to evaluate whether magnesium sulfate administration for neuroprotection prolongs latency in women with preterm premature rupture of membranes (PPROM) between 24 and 31(6\\/7) weeks\\' gestation.

  18. Advances in High-Throughput Speed, Low-Latency Communication for Embedded Instrumentation (7th Annual SFAF Meeting, 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Scott

    2012-06-01

    Scott Jordan on "Advances in high-throughput speed, low-latency communication for embedded instrumentation" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  19. Passive adaptation to stress in adulthood after short-term social instability stress during adolescence in mice.

    Science.gov (United States)

    de Lima, A P N; Massoco, C O

    2017-05-01

    This study reports that short-term social instability stress (SIS) in adolescence increases passive-coping in adulthood in male mice. Short-term SIS decreased the latency of immobility and increased the frequency and time of immobility in tail suspension test. These findings support the hypothesis that adolescent stress can induce a passive adaptation to stress in adulthood, even if it is a short period of stress.

  20. TimeTrader: Exploiting Latency Tail to Save Datacenter Energy for On-line Data-Intensive Applications

    OpenAIRE

    Vamanan, Balajee; Sohail, Hamza Bin; Hasan, Jahangir; Vijaykumar, T. N.

    2015-01-01

    Datacenters running on-line, data-intensive applications (OLDIs) consume significant amounts of energy. However, reducing their energy is challenging due to their tight response time requirements. A key aspect of OLDIs is that each user query goes to all or many of the nodes in the cluster, so that the overall time budget is dictated by the tail of the replies’ latency distribution; replies see latency variations both in the network and compute. Previous work proposes to achieve load-proporti...

  1. Amorphous calcium carbonate controls avian eggshell mineralization: A new paradigm for understanding rapid eggshell calcification.

    Science.gov (United States)

    Rodríguez-Navarro, Alejandro B; Marie, Pauline; Nys, Yves; Hincke, Maxwell T; Gautron, Joel

    2015-06-01

    Avian eggshell mineralization is the fastest biogenic calcification process known in nature. How this is achieved while producing a highly crystalline material composed of large calcite columnar single crystals remains largely unknown. Here we report that eggshell mineral originates from the accumulation of flat disk-shaped amorphous calcium carbonate (ACC) particles on specific organic sites on the eggshell membrane, which are rich in proteins and sulfated proteoglycans. These structures known as mammillary cores promote the nucleation and stabilization of a amorphous calcium carbonate with calcitic short range order which predetermine the calcite composition of the mature eggshell. The amorphous nature of the precursor phase was confirmed by the diffuse scattering of X-rays and electrons. The nascent calcitic short-range order of this transient mineral phase was revealed by infrared spectroscopy and HRTEM. The ACC mineral deposited around the mammillary core sites progressively transforms directly into calcite crystals without the occurrence of any intermediate phase. Ionic speciation data suggest that the uterine fluid is equilibrated with amorphous calcium carbonate, throughout the duration of eggshell mineralization process, supporting that this mineral phase is constantly forming at the shell mineralization front. On the other hand, the transient amorphous calcium carbonate mineral deposits, as well as the calcite crystals into which they are converted, form by the ordered aggregation of nanoparticles that support the rapid mineralization of the eggshell. The results of this study alter our current understanding of avian eggshell calcification and provide new insights into the genesis and formation of calcium carbonate biominerals in vertebrates. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Objective markers for sleep propensity: comparison between the Multiple Sleep Latency Test and the Vigilance Algorithm Leipzig.

    Science.gov (United States)

    Olbrich, Sebastian; Fischer, Marie M; Sander, Christian; Hegerl, Ulrich; Wirtz, Hubert; Bosse-Henck, Andrea

    2015-08-01

    The regulation of wakefulness is important for high-order organisms. Its dysregulation is involved in the pathomechanism of several psychiatric disorders. Thus, a tool for its objective but little time-consuming assessment would be of importance. The Vigilance Algorithm Leipzig allows the objective measurement of sleep propensity, based on a single resting state electroencephalogram. To compare the Vigilance Algorithm Leipzig with the standard for objective assessment of excessive daytime sleepiness, a four-trial Multiple Sleep Latency Test in 25 healthy subjects was conducted. Between the first two trials, a 15-min, 25-channel resting electroencephalogram was recorded, and Vigilance Algorithm Leipzig was used to classify the sleep propensity (i.e., type of vigilance regulation) of each subject. The results of both methods showed significant correlations with the Epworth Sleepiness Scale (ρ = -0.70; ρ = 0.45, respectively) and correlated with each other (ρ = -0.54). Subjects with a stable electroencephalogram-vigilance regulation yielded significant increased sleep latencies compared with an unstable regulation (multiple sleep latency 898.5 s versus 549.9 s; P = 0.03). Further, Vigilance Algorithm Leipzig classifications allowed the identification of subjects with average sleep latencies Sleep Latency Test. Due to its high sensitivity and specificity for large sleep propensity, Vigilance Algorithm Leipzig could be an effective and reliable alternative to the Multiple Sleep Latency Test, for example for screening purposes in large cohorts, where objective information about wakefulness regulation is needed. © 2015 European Sleep Research Society.

  3. The variability of motor evoked potential latencies in neurosurgical motor mapping by preoperative navigated transcranial magnetic stimulation.

    Science.gov (United States)

    Sollmann, Nico; Bulubas, Lucia; Tanigawa, Noriko; Zimmer, Claus; Meyer, Bernhard; Krieg, Sandro M

    2017-01-03

    Recording of motor evoked potentials (MEPs) is used during navigated transcranial magnetic stimulation (nTMS) motor mapping to locate motor function in the human brain. However, factors potentially underlying MEP latency variability in neurosurgical motor mapping are vastly unknown. In the context of this study, one hundred brain tumor patients underwent preoperative nTMS-based motor mapping of the tumor hemisphere between 2010 and 2013. Fourteen predefined predictor variables were recorded, and MEP latencies of abductor pollicis brevis muscle (APB), abductor digiti minimi muscle (ADM), and flexor carpi radialis muscle (FCR) were analyzed using linear mixed-effect multiple regression analysis with the forward step-wise model comparison approach. Common factors (relevant to APB, ADM, and FCR) for MEP latency variability were gender, most likely due to body height, and antiepileptic drug (AED) intake. Muscle-specific factors (relevant to APB, ADM, or FCR) for MEP latency variability were resting motor threshold (rMT), tumor side, and tumor location. Based on a large cohort of neurosurgical patients, this study provides data on a wide range of clinical factors that may underlie MEP latency variability. The factors that significantly contributed to MEP latency variability should be standardly recorded and taken into consideration during neurosurgical motor mapping.

  4. The sequence of cortical activity inferred by response latency variability in the human ventral pathway of face processing.

    Science.gov (United States)

    Lin, Jo-Fu Lotus; Silva-Pereyra, Juan; Chou, Chih-Che; Lin, Fa-Hsuan

    2018-04-11

    Variability in neuronal response latency has been typically considered caused by random noise. Previous studies of single cells and large neuronal populations have shown that the temporal variability tends to increase along the visual pathway. Inspired by these previous studies, we hypothesized that functional areas at later stages in the visual pathway of face processing would have larger variability in the response latency. To test this hypothesis, we used magnetoencephalographic data collected when subjects were presented with images of human faces. Faces are known to elicit a sequence of activity from the primary visual cortex to the fusiform gyrus. Our results revealed that the fusiform gyrus showed larger variability in the response latency compared to the calcarine fissure. Dynamic and spectral analyses of the latency variability indicated that the response latency in the fusiform gyrus was more variable than in the calcarine fissure between 70 ms and 200 ms after the stimulus onset and between 4 Hz and 40 Hz, respectively. The sequential processing of face information from the calcarine sulcus to the fusiform sulcus was more reliably detected based on sizes of the response variability than instants of the maximal response peaks. With two areas in the ventral visual pathway, we show that the variability in response latency across brain areas can be used to infer the sequence of cortical activity.

  5. New oligonucleotide microarray for rapid diagnosis of avian viral diseases.

    Science.gov (United States)

    Sultankulova, Kulyaisan T; Kozhabergenov, Nurlan S; Strochkov, Vitaliy M; Burashev, Yerbol D; Shorayeva, Kamshat A; Chervyakova, Olga V; Rametov, Nurkuisa M; Sandybayev, Nurlan T; Sansyzbay, Abylay R; Orynbayev, Mukhit B

    2017-04-05

    We developed a new oligonucleotide microarray comprising 16 identical subarrays for simultaneous rapid detection of avian viruses: avian influenza virus (AIV), Newcastle disease virus (NDV), infection bronchitis virus (IBV), and infectious bursal disease virus (IBDV) in single- and mixed-virus infections. The objective of the study was to develop an oligonucleotide microarray for rapid diagnosis of avian diseases that would be used in the course of mass analysis for routine epidemiological surveillance owing to its ability to test one specimen for several infections. The paper describes the technique for rapid and simultaneous diagnosis of avian diseases such as avian influenza, Newcastle disease, infectious bronchitis and infectious bursal disease with use of oligonucleotide microarray, conditions for hybridization of fluorescent-labelled viral cDNA on the microarray and its specificity tested with use of AIV, NDV, IBV, IBDV strains as well as biomaterials from poultry. Sensitivity and specificity of the developed microarray was evaluated with use of 122 specimens of biological material: 44 cloacal swabs from sick birds and 78 tissue specimens from dead wild and domestic birds, as well as with use of 15 AIV, NDV, IBV and IBDV strains, different in their origin, epidemiological and biological characteristics (RIBSP Microbial Collection). This microarray demonstrates high diagnostic sensitivity (99.16% within 95% CI limits 97.36-100%) and specificity (100%). Specificity of the developed technique was confirmed by direct sequencing of NP and M (AIV), VP2 (IBDV), S1 (IBV), NP (NDV) gene fragments. Diagnostic effectiveness of the developed DNA microarray is 99.18% and therefore it can be used in mass survey for specific detection of AIV, NDV, IBV and IBDV circulating in the region in the course of epidemiological surveillance. Rather simple method for rapid diagnosis of avian viral diseases that several times shortens duration of assay versus classical diagnostic

  6. Model-based evaluation of highly and low pathogenic avian influenza dynamics in wild birds.

    Directory of Open Access Journals (Sweden)

    Viviane Hénaux

    Full Text Available There is growing interest in avian influenza (AI epidemiology to predict disease risk in wild and domestic birds, and prevent transmission to humans. However, understanding the epidemic dynamics of highly pathogenic (HPAI viruses remains challenging because they have rarely been detected in wild birds. We used modeling to integrate available scientific information from laboratory and field studies, evaluate AI dynamics in individual hosts and waterfowl populations, and identify key areas for future research. We developed a Susceptible-Exposed-Infectious-Recovered (SEIR model and used published laboratory challenge studies to estimate epidemiological parameters (rate of infection, latency period, recovery and mortality rates, considering the importance of age classes, and virus pathogenicity. Infectious contact leads to infection and virus shedding within 1-2 days, followed by relatively slower period for recovery or mortality. We found a shorter infectious period for HPAI than low pathogenic (LP AI, which may explain that HPAI has been much harder to detect than LPAI during surveillance programs. Our model predicted a rapid LPAI epidemic curve, with a median duration of infection of 50-60 days and no fatalities. In contrast, HPAI dynamics had lower prevalence and higher mortality, especially in young birds. Based on field data from LPAI studies, our model suggests to increase surveillance for HPAI in post-breeding areas, because the presence of immunologically naïve young birds is predicted to cause higher HPAI prevalence and bird losses during this season. Our results indicate a better understanding of the transmission, infection, and immunity-related processes is required to refine predictions of AI risk and spread, improve surveillance for HPAI in wild birds, and develop disease control strategies to reduce potential transmission to domestic birds and/or humans.

  7. Impact of the Ku complex on HIV-1 expression and latency.

    Directory of Open Access Journals (Sweden)

    Gwenola Manic

    Full Text Available Ku, a cellular complex required for human cell survival and involved in double strand break DNA repair and multiple other cellular processes, may modulate retroviral multiplication, although the precise mechanism through which it acts is still controversial. Recently, Ku was identified as a possible anti-human immunodeficiency virus type 1 (HIV-1 target in human cells, in two global approaches. Here we investigated the role of Ku on the HIV-1 replication cycle by analyzing the expression level of a panel of non-replicative lentiviral vectors expressing the green fluorescent protein in human colorectal carcinoma HCT 116 cells, stably or transiently depleted of Ku. We found that in this cellular model the depletion of Ku did not affect the efficiency of (pre-integrative steps but decreased the early HIV-1 expression by acting at the transcriptional level. This negative effect was specific of the HIV-1 promoter, required the obligatory step of viral DNA integration and was reversed by transient depletion of p53. We also provided evidence on a direct binding of Ku to HIV-1 LTR in transduced cells. Ku not only promotes the early transcription from the HIV-1 promoter, but also limits the constitution of viral latency. Moreover, in the presence of a normal level of Ku, HIV-1 expression was gradually lost over time, likely due to the counter-selection of HIV-1-expressing cells. On the contrary, the reactivation of transgene expression from HIV-1 by means of trichostatin A- or tumor necrosis factor α-administration was enhanced under condition of Ku haplodepletion, suggesting a phenomenon of provirus latency. These observations plead in favor of the hypothesis that Ku has an impact on HIV-1 expression and latency at early- and mid-time after integration.

  8. Characterising the association of latency with α1-antitrypsin polymerisation using a novel monoclonal antibody

    Science.gov (United States)

    Tan, Lu; Perez, Juan; Mela, Marianna; Miranda, Elena; Burling, Keith A; Rouhani, Farshid N; DeMeo, Dawn L; Haq, Imran; Irving, James A; Ordóñez, Adriana; Dickens, Jennifer A; Brantly, Mark; Marciniak, Stefan J; Alexander, Graeme J M; Gooptu, Bibek; Lomas, David A

    2015-01-01

    α1-Antitrypsin is primarily synthesised in the liver, circulates to the lung and protects pulmonary tissues from proteolytic damage. The Z mutant (Glu342Lys) undergoes inactivating conformational change and polymerises. Polymers are retained within the hepatocyte endoplasmic reticulum (ER) in homozygous (PiZZ) individuals, predisposing the individuals to hepatic cirrhosis and emphysema. Latency is an analogous process of inactivating, intra-molecular conformational change and may co-occur with polymerisation. However, the relationship between latency and polymerisation remained unexplored in the absence of a suitable probe. We have developed a novel monoclonal antibody specific for latent α1-antitrypsin and used it in combination with a polymer-specific antibody, to assess the association of both conformers in vitro, in disease and during augmentation therapy. In vitro kinetics analysis showed polymerisation dominated the pathway but latency could be promoted by stabilising monomeric α1-antitrypsin. Polymers were extensively produced in hepatocytes and a cell line expressing Z α1-antitrypsin but the latent protein was not detected despite manipulation of the secretory pathway. However, α1-antitrypsin augmentation therapy contains latent α1-antitrypsin, as did the plasma of 63/274 PiZZ individuals treated with augmentation therapy but 0/264 who were not receiving this medication (p < 10−14). We conclude that latent α1-antitrypsin is a by-product of the polymerisation pathway, that the intracellular folding environment is resistant to formation of the latent conformer but that augmentation therapy introduces latent α1-antitrypsin into the circulation. A suite of monoclonal antibodies and methodologies developed in this study can characterise α1-antitrypsin folding and conformational transitions, and screen methods to improve augmentation therapy. PMID:25462157

  9. Low luminance/eyes closed and monochromatic stimulations reduce variability of flash visual evoked potential latency

    Directory of Open Access Journals (Sweden)

    Senthil Kumar Subramanian

    2013-01-01

    Full Text Available Context: Visual evoked potentials are useful in investigating the physiology and pathophysiology of the human visual system. Flash visual evoked potential (FVEP, though technically easier, has less clinical utility because it shows great variations in both latency and amplitude for normal subjects. Aim: To study the effect of eye closure, low luminance, and monochromatic stimulation on the variability of FVEPs. Subjects and Methods: Subjects in self-reported good health in the age group of 18-30 years were divided into three groups. All participants underwent FVEP recording with eyes open and with white light at 0.6 J luminance (standard technique. Next recording was done in group 1 with closed eyes, group 2 with 1.2 and 20 J luminance, and group 3 with red and blue lights, while keeping all the other parameters constant. Two trials were given for each eye, for each technique. The same procedure was repeated at the same clock time on the following day. Statistical Analysis: Variation in FVEP latencies between the individuals (interindividual variability and the variations within the same individual for four trials (intraindividual variability were assessed using coefficient of variance (COV. The technique with lower COV was considered the better method. Results: Recording done with closed eyes, 0.6 J luminance, and monochromatic light (blue > red showed lower interindividual and intraindividual variability in P2 and N2 as compared to standard techniques. Conclusions: Low luminance flash stimulations and monochromatic light will reduce FVEP latency variability and may be clinically useful modifications of FVEP recording technique.

  10. [Multiple sleep latency test, maintenance of wakefulness test and suggestive immobilization test].

    Science.gov (United States)

    Tanaka, Haruhito

    2015-06-01

    In clinical practice, assessment usually involves self-report; however, objective measures are available. The multiple sleep latency test(MSLT) is performed during the main period of wakefulness and is designed to determine a patient's propensity to fall asleep. To be valid, the MSLT should be performed the day after nocturnal polysomnography (PSG). It is the standard test for the assessment of objective sleepiness and diagnosis of narcolepsy, that is a mean sleep latency equal to or under 8 minutes and equal to or greater than two sleep onset REM periods (SOREMPs). As opposed to the MSLT, the maintenance of wakefulness test (MWT) is designed to test the patient's ability to stay awake. The MWT is a 40-minutes protocol consisting of four trials separated by 2-hour intervals and is performed in much the same way as the MSLT. The MWT may be indicated in assessment of individuals in whom the inability to remain awake constitutes a safety issue, or in patients with narcolepsy or idiopathic hypersomnia to assess response to treatment with medications. There is little evidence linking mean sleep latency on the MWT with risk of accidents in real world circumstances. The suggestive immobilization test(SIT) was designed during which sensor and motor symptoms of restless legs syndrome are quantified during a period of immobility taking place in the evening before PSG. The patient is instructed to avoid moving voluntary for the entire duration of the test, which is designed to last 1 hour. The subjective leg discomfort evaluation and periodic leg movement by surface electromyograms from right and left anterior tibialis support diagnosis for restless legs syndrome. Many factors, such as clinical setting, pretest condition or aging effects etc. can alter the findings of the test and considerable clinical judgment is needed to avoid an error in interpretation. Above those three sleep-wake related tests provide us useful information.

  11. CD8 T cells control cytomegalovirus latency by epitope-specific sensing of transcriptional reactivation.

    Science.gov (United States)

    Simon, Christian O; Holtappels, Rafaela; Tervo, Hanna-Mari; Böhm, Verena; Däubner, Torsten; Oehrlein-Karpi, Silke A; Kühnapfel, Birgit; Renzaho, Angélique; Strand, Dennis; Podlech, Jürgen; Reddehase, Matthias J; Grzimek, Natascha K A

    2006-11-01

    During murine cytomegalovirus (mCMV) latency in the lungs, most of the viral genomes are transcriptionally silent at the major immediate-early locus, but rare and stochastic episodes of desilencing lead to the expression of IE1 transcripts. This low-frequency but perpetual expression is accompanied by an activation of lung-resident effector-memory CD8 T cells specific for the antigenic peptide 168-YPHFMPTNL-176, which is derived from the IE1 protein. These molecular and immunological findings were combined in the "silencing/desilencing and immune sensing hypothesis" of cytomegalovirus latency and reactivation. This hypothesis proposes that IE1 gene expression proceeds to cell surface presentation of the IE1 peptide by the major histocompatibility complex (MHC) class I molecule L(d) and that its recognition by CD8 T cells terminates virus reactivation. Here we provide experimental evidence in support of this hypothesis. We generated mutant virus mCMV-IE1-L176A, in which the antigenic IE1 peptide is functionally deleted by a point mutation of the C-terminal MHC class I anchor residue Leu into Ala. Two revertant viruses, mCMV-IE1-A176L and the wobble nucleotide-marked mCMV-IE1-A176L*, in which Leu is restored by back-mutation of Ala codon GCA into Leu codons CTA and CTT, respectively, were constructed. Pulmonary latency of the mutant virus was found to be associated with an increased prevalence of IE1 transcription and with events of IE3 transactivator splicing. In conclusion, IE1-specific CD8 T cells recognize and terminate virus reactivation in vivo at the first opportunity in the reactivated gene expression program. The perpetual gene expression and antigen presentation might represent the driving molecular force in CMV-associated immunosenescence.

  12. Intracellular-activated Notch1 can reactivate Kaposi's sarcoma-associated herpesvirus from latency

    International Nuclear Information System (INIS)

    Lan, Ke; Murakami, Masanao; Choudhuri, Tathagata; Kuppers, Daniel A.; Robertson, Erle S.

    2006-01-01

    Kaposi's sarcoma-associated herpesvirus (KSHV) establishes a predominantly latent infection in the infected host. Importantly, during latency, only a small number of viral encoded genes are expressed. This viral gene expression pattern contributes to the establishment of long-term infection as well as the ability of the virus to evade the immune system. Previous studies have been shown that the replication and transcription activator (RTA) encoded by ORF50 activates it downstream genes and initiates viral lytic reactivation through functional interaction with RBP-Jκ, the major downstream effector of the Notch signaling pathway. This indicates that RTA can usurp the conserved Notch signaling pathway and mimic the activities of intracellular Notch1 to modulate gene expression. In this report, we show that the activated intracellular domain of Notch1 (ICN) is aberrantly accumulated in KSHV latently infected pleural effusion lymphoma (PEL) cells. ICN activated the RTA promoter in a dose-dependent manner, and forced expression of ICN in latently infected KSHV-positive cells initiated full blown lytic replication with the production of infectious viral progeny. However, latency-associated nuclear antigen (LANA) which is predominantly expressed during latency can specifically down-modulate ICN-mediated transactivation of RTA and so control KSHV for lytic reactivation. These results demonstrate that LANA can inhibit viral lytic replication by antagonizing ICN function and suggest that LANA is a critical component of the regulatory control mechanism for switching between viral latent and lytic replication by directly interacting with effectors of the conserved cellular Notch1 pathway

  13. MicroRNA regulation of viral immunity, latency, and carcinogenesis of selected tumor viruses and HIV.

    Science.gov (United States)

    Wang, Ling; Li, Guangyu; Yao, Zhi Q; Moorman, Jonathan P; Ning, Shunbin

    2015-09-01

    MicroRNAs (miRNAs) function as key regulators in immune responses and cancer development. In the contexts of infection with oncogenic viruses, miRNAs are engaged in viral persistence, latency establishment and maintenance, and oncogenesis. In this review, we summarize the potential roles and mechanisms of viral and cellular miRNAs in the host-pathogen interactions during infection with selected tumor viruses and HIV, which include (i) repressing viral replication and facilitating latency establishment by targeting viral transcripts, (ii) evading innate and adaptive immune responses via toll-like receptors, RIG-I-like receptors, T-cell receptor, and B-cell receptor pathways by targeting signaling molecules such as TRAF6, IRAK1, IKKε, and MyD88, as well as downstream targets including regulatory cytokines such as tumor necrosis factor α, interferon γ, interleukin 10, and transforming growth factor β, (iii) antagonizing intrinsic and extrinsic apoptosis pathways by targeting pro-apoptotic or anti-apoptotic gene transcripts such as the Bcl-2 family and caspase-3, (iv) modulating cell proliferation and survival through regulation of the Wnt, PI3K/Akt, Erk/MAPK, and Jak/STAT signaling pathways, as well as the signaling pathways triggered by viral oncoproteins such as Epstein-Barr Virus LMP1, by targeting Wnt-inhibiting factor 1, SHIP, pTEN, and SOCSs, and (v) regulating cell cycle progression by targeting cell cycle inhibitors such as p21/WAF1 and p27/KIP1. Further elucidation of the interaction between miRNAs and these key biological events will facilitate our understanding of the pathogenesis of viral latency and oncogenesis and may lead to the identification of miRNAs as novel targets for developing new therapeutic or preventive interventions. Copyright © 2015 John Wiley & Sons, Ltd.

  14. Shift of the Muscular Inhibition Latency during On-Line Acquisition of Anticipatory Postural Adjustments.

    Directory of Open Access Journals (Sweden)

    Fanny Barlaam

    Full Text Available During action, Anticipatory Postural Adjustments (APAs cancel the consequences of a movement on postural stabilization. Their muscular expression is characterized by early changes in the activity of the postural muscles, before the movement begins. To explore the mechanisms enabling the acquisition of APAs, a learning paradigm was designed in which the voluntary lifting of a load with one hand triggered the unloading of another load suspended below the contralateral forearm. The aim of this study was to investigate changes in the muscular expression that uncovers the progressive learning of new APAs. A trial-by-trial analysis of kinematic and electromyographic signals recorded on the right arm was conducted in twelve adults through six sessions of learning. Kinematic results reported an enhancement of the postural stabilization across learning. The main EMG pattern found during learning consisted of a flexor inhibition, where latency was shifted towards an earlier occurrence in parallel with the improvement of the postural performance. A linear regression analysis conducted between the inhibition latency and the maximal amplitude of elbow rotation showed that the earlier the inhibition onset, the better the postural stabilization. This study revealed that the progressive shift of the postural flexor inhibition latency could be considered as a reliable neurophysiological marker of the progressive learning of new APAs. Importantly, this marker could be used to track motor learning abnormalities in pathology. We relate our findings to the update of a forward predictive model of action, defined as a system that predicts beforehand the consequences of the action on posture.

  15. Ultra-high speed and low latency broadband digital video transport

    Science.gov (United States)

    Stufflebeam, Joseph L.; Remley, Dennis M.; Sullivan, Anthony; Gurrola, Hector

    2004-07-01

    Various approaches for transporting digital video over Ethernet and SONET networks are presented. Commercial analog and digital frame grabbers are utilized, as well as software running under Microsoft Windows 2000/XP. No other specialized hardware is required. A network configuration using independent VLANs for video channels provides efficient transport for high bandwidth data. A framework is described for implementing both uncompressed and compressed streaming with standard and non-standard video. NTSC video is handled as well as other formats that include high resolution CMOS, high bit-depth infrared, and high frame rate parallel digital. End-to-end latencies of less than 200 msec are achieved.

  16. Calcium dependence of uni-quantal release latencies and quantal content at mouse neuromuscular junction

    Czech Academy of Sciences Publication Activity Database

    Samigullin, D.; Bukharaeva, E. A.; Vyskočil, František; Nikolsky, E. E.

    2005-01-01

    Roč. 54, č. 1 (2005), s. 129-132 ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA5011411; GA ČR(CZ) GA305/02/1333 Grant - others:RFBR(RU) 05-04-49723; Russian Science Support Foundation(RU) 1063.2003.4; GA-(RU) MK-2153.2003.04 Institutional research plan: CEZ:AV0Z50110509 Keywords : quantal release * synaptic latency * calcium Subject RIV: ED - Physiology Impact factor: 1.806, year: 2005

  17. Without Latency: Cathode Immersions and the Neglected Practice of Xenocasting for Television and Radio

    Directory of Open Access Journals (Sweden)

    Adam Hulbert

    2015-09-01

    Full Text Available This paper discusses a three-year radio project Cathode Immersions, which was aired on 2SER in Sydney Australia. The audio that accompanied free-to-air television was remixed and rebroadcast in real time without latency. It explores the human and non-human aspects of the convergence of these two media, introducing ideas of xenocasting and media adjacency. The weekly xenocast of Cathode Immersions afforded unique translations of cultural narratives, from commentary on the Gulf War to machinic perspectives on the desires that surround commercial broadcasting.

  18. Analysis of Latency and MAC-layer Performance for Class A LoRaWAN

    DEFF Research Database (Denmark)

    Sørensen, René Brandborg; Kim, Dong Min; Nielsen, Jimmy Jessen

    2017-01-01

    We propose analytical models that allow to investigate the performance of Long Range Wide Area Network (LoRaWAN) uplink in terms of latency, collision rate, and throughput under the constraints of the regulatory duty cycling, when assuming exponential inter-arrival times. Our models take...... a large effect on the QoS experienced in a LoRaWAN cell for a given load. The proposed models allow for optimizing resource allocation within a cell given a set of QoS requirements and a traffic model....

  19. Temporal suppression of long-latency click-evoked otoacoustic emissions

    DEFF Research Database (Denmark)

    Verhulst, Sarah; Harte, James; Dau, Torsten

    2007-01-01

    A comprehensive set of results from double click suppression experiments on otoacoustic emissions (OAEs) have been presented by Hine and Thornton (2002) and Kapadia and Lutman (2000). They found that suppression of a click-evoked otoacoustic emission (CEOAE) varied with the timing and level...... subjects showed that the nonlinear suppression effect remained on the long-latency CEOAE, indicating that both SOAEs and CEOAEs originate from the same cochlear nonlinearities, as earlier suggested by Kemp and Chum (1980). The apparent similar origin of both types of emissions implies that the same...

  20. Interruption of the latency in seeds to inclination of technical nuclear

    International Nuclear Information System (INIS)

    Ramos Espinosa, K.A.; Damera Martinez, A.; Benito Zamora, E.; Vazquez Hernandez, L.

    2001-01-01

    The relatively long periods of cheats that it plows required to carry out the germination tests have blocked the progress toward the biggest efficiency in the obtaining of good plants for plantation and the it leaves operations. The long periods that plows required for the germination of many classes of seeds constitute one of the manifestations of the quality of latent that have some seeds. Leucaena seeds and Chinese pumpkin were studied for which it was possible to interrupt the latency and with this to be able to obtain bigger for hundred of germination in to term of briefer it cheats