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Journal articles on the topic 'Duration and latency'
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Henao-Martínez, Andrés F., Sindhu Chadalawada, Wilmer E. Villamil-Gomez, Kristen DeSanto, Anis Rassi, and Carlos Franco-Paredes. "Duration and determinants of Chagas latency." JBI Database of Systematic Reviews and Implementation Reports 17, no. 10 (2019): 2122–28. http://dx.doi.org/10.11124/jbisrir-d-18-00018.
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Gridley, Mark C., James L. Mack, and Grover C. Gilmore. "Age Effects on a Nonverbal Auditory Sustained Attention Task." Perceptual and Motor Skills 62, no. 3 (1986): 911–17. http://dx.doi.org/10.2466/pms.1986.62.3.911.
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A nonverbal auditory test of sustained attention was administered to 20 young and 20 elderly women, screened to ensure good health. Groups were matched for intelligence. Older subjects performed as accurately as younger subjects. Neither group showed increases in response latency as a function of time spent on test. Older subjects took longer to respond than younger subjects, but only for a particular combination of stimulus duration and order of presenting stimulus durations. When subjects were presented long tones first, there was no difference in response latency associated with age or stimulus duration. When short tones were presented first, older subjects were slower than younger subjects in both duration conditions and in response to long tones were slower than all other subjects.
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Horstmann, Gernot. "Latency and duration of the action interruption in surprise." Cognition & Emotion 20, no. 2 (2006): 242–73. http://dx.doi.org/10.1080/02699930500262878.
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Bachiocco, Valeria, Romano Bragaglia, and Giancarlo Carli. "Latency as predictor of postsurgical pain intensity and duration." Journal of Pain and Symptom Management 7, no. 4 (1992): 190–91. http://dx.doi.org/10.1016/0885-3924(92)90073-q.
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Fremouw, Thane, Paul A. Faure, John H. Casseday, and Ellen Covey. "Duration Selectivity of Neurons in the Inferior Colliculus of the Big Brown Bat: Tolerance to Changes in Sound Level." Journal of Neurophysiology 94, no. 3 (2005): 1869–78. http://dx.doi.org/10.1152/jn.00253.2005.
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At and above the level of the inferior colliculus (IC), some neurons respond maximally to a limited range of sound durations, with little or no excitatory response to durations outside of this range. Such neurons have been termed “duration tuned” or “duration selective.” In this study we examined the effects of varying signal amplitude on best duration, width of tuning, and first spike latency of duration tuned neurons in the IC of the big brown bat, Eptesicus fuscus. Response areas as a function of stimulus duration and intensity took a variety of forms, including open (V-shaped), narrow and level tolerant (U-shaped), or closed (O-shaped). The majority (82%) of duration tuned neurons had narrow U-shaped or O-shaped duration response areas. Those with narrow U-shaped response areas retained their duration tuning across a broad dynamic range, ≤50 dB above threshold, whereas those with O-shaped response areas were narrowly tuned to both stimulus duration and amplitude. For about one-half (55%) of the neurons with either a U- or O-shaped response areas, best duration (BD) changed by <1 ms across the range of suprathreshold amplitudes tested. Changes in BD most often took the form of a shift to slightly shorter durations as stimulus level increased. For the majority (65%) of U- and O-shaped neurons, 50% width of duration tuning changed by <2 ms with increasing amplitude. Latency of response at BD remained stable across changes in sound level, suggesting that the relative strengths of excitatory and inhibitory inputs to duration tuned neurons remain in balance over a wide dynamic range of sound pressure levels.
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Losonczy-Marshall, Marta E. "GENDER DIFFERENCES IN LATENCY AND DURATION OF EMOTIONAL EXPRESSION IN 7- THROUGH 13-MONTH-OLD INFANTS." Social Behavior and Personality: an international journal 36, no. 2 (2008): 267–74. http://dx.doi.org/10.2224/sbp.2008.36.2.267.
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A total of 82 infants aged 7 through 13 months were each presented with a randomized order of stimuli in a large descriptive study. All infants passed developmental screening tests (5-minute Apgar and Denver II; Apgar, 1953; Frankenburg & Dodds, 1990). Emotional expressions in response to the stimuli were recorded by video. Male and female infants' responses to 5 social stimuli (82 × 5 = 410 observations) were analyzed. Latency was the time between the presentation of a stimulus and the beginning of a facial expression in response to that stimulus. Duration was the time between the beginning of a facial expression and the end of that facial expression. Both latency and duration were measured in terms of time (seconds). Gender differences were found in latency: t = 2.41, p < .05, but not duration of emotional expression. Females had shorter latency to emotional expression and longer duration of emotional expression than males.
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Homma, Yuko, Yutaka Homma, Luis Teneud, et al. "Effects of rotation on the P13 mid-latency auditory evoked potential in Rat." Journal of Vestibular Research 12, no. 2-3 (2003): 117–25. http://dx.doi.org/10.3233/ves-2003-122-306.
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The P13 mid-latency auditory evoked potential in Rat is a sleep state-dependent response thought to be equivalent to the human P50 potential, a measure of the output of the reticular activating system. The amplitude of these potentials can be considered a measure of level of arousal, while, using a paired stimulus paradigm, the degree of habituation of the responses also can be assessed. Different durations of rotation were found to reduce the amplitude of the P13 potential, which recovered in a duration-dependent manner. Different durations of rotation led to decreases in habituation of the P13 potential again in a duration-dependent manner. These results suggest that rotation may affect the level of arousal as well as habituation to repetitive sensory inputs. Such effects could be interpreted to imply the presence, following rotation of sufficient duration, of a deficit in sensory gating, or distractibility, and are relevant for the study of the effects of space motion sickness.
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Frolov, Roman V., and Irina I. Ignatova. "Speed of phototransduction in the microvillus regulates the accuracy and bandwidth of the rhabdomeric photoreceptor." PLOS Computational Biology 16, no. 11 (2020): e1008427. http://dx.doi.org/10.1371/journal.pcbi.1008427.
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Phototransduction reactions in the rhabdomeric photoreceptor are profoundly stochastic due to the small number of participating molecules and small reaction space. The resulting quantum bumps (QBs) vary in their timing (latency), amplitudes and durations, and these variabilities within each cell are not correlated. Using modeling and electrophysiological recordings, we investigated how the QB properties depend on the cascade speed and how they influence signal transfer. Parametric analysis in the model supported by experimental data revealed that faster cascades elicit larger and narrower QBs with faster onsets and smaller variabilities than slower cascades. Latency dispersion was stronger affected by modification of upstream than downstream activation parameters. The variability caused by downstream modifications closely matched the experimental variability. Frequency response modeling showed that corner frequency is a reciprocal function of the characteristic duration of the multiphoton response, which, in turn, is a non-linear function of QB duration and latency dispersion. All QB variabilities contributed noise but only latency dispersion slowed and spread multiphoton responses, lowering the corner frequency. Using the discovered QB correlations, we evaluated transduction noise for dissimilar species and two extreme adaptation states, and compared it to photon noise. The noise emitted by the cascade was non-additive and depended non-linearly on the interaction between the QB duration and the three QB variabilities. Increased QB duration strongly suppressed both noise and corner frequency. This trade-off might be acceptable for nocturnal but not diurnal species because corner frequency is the principal determinant of information capacity. To offset the increase in noise accompanying the QB narrowing during light adaptation and the response-expanding effect of latency dispersion, the cascade accelerates. This explains the widespread evolutionary tendency of diurnal fliers to have fast phototransduction, especially after light adaptation, which thus appears to be a common adaptation to contain stochasticity, improve SNR and expand the bandwidth.
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IYASERE, O. S., I. J. JAMES, A. B. ADESUPO, I. C. NWOSU, and J. O. DARAMOLA. "PARTUM AND POST-PARTUM BEHAVIOURS OF WEST AFRICAN DWARF DOES AND KIDS." Journal of Agricultural Science and Environment 19, no. 1 (2020): 195–201. http://dx.doi.org/10.51406/jagse.v19i1.2026.
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Seventeen West African Dwarf does housed intensively were used for this study. Does were naturally mated and pregnancy was confirmed by non-return to oestrus. The predicted parturition date was calculated. Two days to the predicted date of parturition, the does were closely monitored until the day they actually kidded. The behaviours of the does (duration of parturition, and latency to groom kids) and the kids (latency to stand) were recorded. Data were subjected to independent T-test of SPSS statistical package. The mean duration of parturition in WAD does was 9.5±2.65 min and the latency of kids to stand was 10.5±3.45mins. Duration of parturition was greater (P<0.05) in the 1st than 2nd parity does. A significant negative correlation was established between parity and duration of parturition (r =-0.635, P˂0.05). Kids from 1st parity does stood up earlier (P<0.05) compared to those from the 2nd parity does. A positive correlation was established between parity and the latency of the kids to stand (r = 0.598, P˂0.05). In conclusion, the duration of parturition and latency of kid to stand were not affected by the sex of the kid delivered, however WAD does groomed female kids earlier than the male kids. 
 
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Puri, Manju, Neha Gami, and Seema Singhal. "An Analysis of Factors Affecting the Duration of Latency Period and Its Impact on Neonatal Outcome in Patients with PPROM." International Journal of Infertility & Fetal Medicine 3, no. 3 (2012): 87–91. http://dx.doi.org/10.5005/jp-journals-10016-1048.
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ABSTRACT Introduction Preterm premature rupture of membranes (PPROM) complicates approximately 3% of all births, but accounts for 30% of neonatal morbidity and mortality among premature gestations. Prediction of latency period for women with PPROM is imprecise and therefore consulting women with PPROM about their predicted latency period is a difficult task. The studies are limited, thus more information is required to support clinical decisions and to provide prognostic information in cases of expectant management following PPROM. Materials and methods We conducted a prospective observational study of women with singleton pregnancies presenting with rupture of membranes. A total of 120 women presenting with PPROM from 26 to 36 weeks with rupture of membrane were included in this study. Results Advanced maternal age >30 years was found to be associated with prolongation of latency period (p = 0.000). Nulliparity was found to be associated with shortening of latency period (p = 0.012). An inverse association between gestational age at the time of presentation and latency period was established. The average gain in duration of latency period by not doing a digital examination was found to be statistically significant (p = 0.000). Gestational age and duration of latency period were found to be the important predictors of neonatal outcome. Conclusion In the current study, several predictive factors were identified which affect the duration of the latency period in cases of PPROM. This information may assist clinician in risk stratification and in providing consultation regarding the natural course of expectant management for women presenting with PPROM. How to cite this article Singhal S, Puri M, Gami N. An Analysis of Factors Affecting the Duration of Latency Period and Its Impact on Neonatal Outcome in Patients with PPROM. Int J Infertility Fetal Med 2012;3(3):87-91.
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Venkova, K., and J. Krier. "A nitric oxide and prostaglandin-dependent component of NANC off-contractions in cat colon." American Journal of Physiology-Gastrointestinal and Liver Physiology 266, no. 1 (1994): G40—G47. http://dx.doi.org/10.1152/ajpgi.1994.266.1.g40.
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The actions of NO synthase inhibitors and indomethacin, a cyclooxygenase inhibitor, on the nonadrenergic noncholinergic (NANC) mechanical responses of cat distal colon were studied in vitro using muscle strips orientated in the axis of the longitudinal muscle layer with pelvic nerves attached. Electrical field stimulation (EFS) or pelvic nerve stimulation (PNS) caused inhibition of spontaneous contractions followed by off-contractions. Indomethacin (10-30 microM) caused concentration-dependent reductions in amplitude and duration of EFS- and PNS-evoked off-contractions but not latency. The NO synthase inhibitors, N omega-nitro-L-arginine (L-NNA), N omega-nitro-L-arginine methyl ester (L-NAME) and NG-monomethyl-L-arginine (L-NMMA) (each at 100 microM) significantly reduced latency, amplitude, and duration of off-contractions evoked by EFS and PNS. This inhibition was partially reversed by L-arginine (120 microM) but not by D-arginine. Incubation of colonic strips with alpha-chymotrypsin (2 U/ml) decreased latency, amplitude, and duration of NANC off-contractions. L-NNA reduced amplitude, duration, and latency of off-contractions in preparations pretreated with alpha-chymotrypsin. Hydroquinone (10-30 microM), a generator of superoxide anions, caused significant depression of amplitude, duration, and latency of off-contractions which was completely reversed by superoxide dismutase (200 U/ml). These data suggest that the components of NANC off-contractions evoked by EFS and PNS involve peptides, NO, and prostaglandins.
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Ritter, Philipp S., Cathrin Sauer, Steffi Pfeiffer, Michael Bauer, and Andrea Pfennig. "Comparison of Subjective and Objective Sleep Estimations in Patients with Bipolar Disorder and Healthy Control Subjects." Sleep Disorders 2016 (2016): 1–5. http://dx.doi.org/10.1155/2016/4031535.
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Background. Several studies have described but not formally tested discrepancies between subjective and objective measures of sleep.Study Objectives. To test the hypothesis that patients with bipolar disorder display a systematic bias to underestimate sleep duration and overestimate sleep latency.Methods. Actimetry was used to assess sleep latency and duration in 49 euthymic participants (bipolar = 21; healthy controls = 28) for 5–7 days. Participants simultaneously recorded estimated sleep duration and sleep latency on a daily basis via an online sleep diary. Group differences in the discrepancy between subjective and objective parameters were calculated usingt-tests and corrected for multiple comparisons.Results. Patients with bipolar disorder significantly underestimated their sleep duration but did not overestimate their sleep latency compared to healthy controls.Conclusions. Studies utilizing diaries or questionnaires alone in patients with bipolar disorders may systematically underestimate sleep duration compared to healthy controls. The additional use of objective assessment methods such as actimetry is advisable.
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Aziz, Natali, Melanie Watkins, and Aaron b. Caughey. "Factors affecting latency duration in preterm premature rupture of membranes." American Journal of Obstetrics and Gynecology 191, no. 6 (2004): S115. http://dx.doi.org/10.1016/j.ajog.2004.10.298.
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Xiao, Li, Kang Zou, Duoyan Zhou, Guilan Ouyang, Shuixiang Liu, and Jun Luo. "Changes of Blink Reflex in Type 2 Diabetes Mellitus." Journal of Diabetes Research 2021 (March 12, 2021): 1–7. http://dx.doi.org/10.1155/2021/2473193.
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Blink reflex provides an objective assessment of the cranial and central nervous systems. However, the relationships between body mass index, dizziness, and BR have not been explored in patients with type 2 diabetes mellitus (T2DM). Moreover, R2 duration, one of the parameters of the blink reflex, has not been studied to date. In the present study, we aimed to investigate the characteristics and influencing factors of blink reflex in patients with T2DM. We included 45 healthy subjects and 105 hospitalized patients with T2DM. The relationships between these parameters and sex, age, body mass index, duration of T2DM, hemoglobin A1c, distal symmetrical polyneuropathy (DSPN), and dizziness symptoms were analyzed. The results showed that blink reflex latencies (including R1, ipsilateral R2, and contralateral R2 latency) were negatively associated with body mass index but were positively correlated with the duration of T2DM. There were no correlations between blink reflex parameters and sex, age, and hemoglobin A1c. Patients with DSPN had longer blink reflex latencies and shorter R2 durations than those without DSPN. Patients with dizziness had longer latencies (including R1, ipsilateral R2, and contralateral R2 latencies) and shorter R2 durations (including ipsilateral R2 and contralateral R2 durations) than those without dizziness. R2 duration was also a predictive factor for blink reflex abnormality. R2 latency was the most sensitive factor and the optimal predictor of dizziness. These results demonstrate that patients with T2DM with low body mass index, longer duration of T2DM, DSPN, and dizziness-related symptoms had more abnormal blink reflex parameters, indicating more serious injuries to the cranial nerves or the central nervous system.
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Bisson, Alycia, Margie Lachman, and Alycia Sullivan Bisson. "Daily Relationships Between Physical Activity and Sleep: Differences Between Subjective and Objective Measures." Innovation in Aging 4, Supplement_1 (2020): 426. http://dx.doi.org/10.1093/geroni/igaa057.1376.
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Abstract Although there is evidence that physical activity (PA) and sleep are related, it is unclear which aspects of these multidimensional constructs are involved. Many have examined differences in PA and sleep between persons, but few have tested daily associations within persons. The present study examined sleep (duration; hours spent asleep, WASO; wake after sleep onset, latency; time to fall asleep) and PA (total and intensity) over 7 days, using both a self-reported diary (subjective) and an ActiWatch (objective). Healthy adults between 34 and 83 came to University of Wisconsin, Madison to participate in the Midlife in the United States (MIDUS) Biomarker study (N=436, Mage: 56.92, SDage: 11.5). Subjective and objective measures showed differential relationships; subjective duration was higher, and latency was lower than objective measures. Some age differences were also found; older adults reported more WASO than middle-aged adults, but their WASO was similar according to actigraphy. Multilevel models revealed that total PA and intensity significantly predicted subjective and objective sleep measures, controlling for age, sex, and other demographic variables. More active participants had shorter sleep durations, WASO, and latency. Within-person analyses revealed that on days one is more active than average, sleep duration is shorter with less WASO across age. Although the negative relationship between PA and sleep duration was unexpected, it is possible that because more active individuals wake less during the night, they may need fewer hours of sleep because their sleep is more restful. Discussion will focus on possible mechanisms involved in linking PA and sleep.
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Ehrlich, Daphna, John H. Casseday, and Ellen Covey. "Neural Tuning to Sound Duration in the Inferior Colliculus of the Big Brown Bat, Eptesicus fuscus." Journal of Neurophysiology 77, no. 5 (1997): 2360–72. http://dx.doi.org/10.1152/jn.1997.77.5.2360.
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Ehrlich, Daphna, John H. Casseday, and Ellen Covey. Neural tuning to sound duration in the inferior colliculus of the big brown bat, Eptesicus fuscus. J. Neurophysiol. 77: 2360–2372, 1997. Neural tuning to different sound durations may be a useful filter for identification of certain sounds, especially those that are biologically important. The auditory midbrains of mammals and amphibians contain neurons that appear to be tuned to sound duration. In amphibians, neurons are tuned to durations of sound that are biologically important. The purpose of this study was to characterize responses of neurons in the inferior colliculus (IC) of the big brown bat, Eptesicus fuscus, to sounds of different durations. Our aims were to determine what percent of neurons are duration tuned and how best durations are correlated to durations of echolocation calls, and to examine response properties that may be relevant to the mechanism for duration tuning, such as latency and temporal firing pattern; we also examined frequency tuning and rate-level functions. We recorded from 136 single units in the central nucleus of the IC of unanesthetized bats. The stimuli were pure tones, frequency-modulated sweeps, and broadband noise. The criterion for duration tuning was an increase in spike count of ≥50% at some durations compared with others. Of the total units sampled, 36% were tuned to stimulus duration. All of these units were located in the caudal half of the IC. Best duration for most units ranged from <1 to 10 ms, but a few had best durations up to ≥20 ms. This range is similar to the range of durations of echolocation calls used by Eptesicus. All duration-tuned neurons responded transiently. The minimum latency was always longer than the best duration. Duration-tuned units have best durations and best frequencies that match the temporal structure and frequency range of the echolocation calls. Thus the results raise the hypothesis that neurons in the IC of Eptesicus, and probably the auditory midbrain of other vertebrates, are tuned to biologically important sound durations. We suggest a model for duration tuning consisting of three components: 1) inhibitory input that is correlated with the onset of the stimulus and is sustained for the stimulus duration; 2) transient excitation that is correlated with the offset of the stimulus; and 3) transient excitation that is correlated with the onset of the stimulus but is delayed in time relative to the onset of inhibition. For the neuron to fire, the two excitatory events must coincide in time; noncoincident excitatory events are not sufficient.
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Eddins, Ann Clock, and Joelle Redner Peterson. "Time-Intensity Trading in the Late Auditory Evoked Potential." Journal of Speech, Language, and Hearing Research 42, no. 3 (1999): 516–25. http://dx.doi.org/10.1044/jslhr.4203.516.
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The present study investigated physiological correlates of the time-intensity trading relationship in late components (N1, P2) of the auditory evoked potential. Late-potential and behavioral thresholds were estimated in five normal-hearing, young adult participants for 1000- and 4000-Hz tone bursts having durations of 8, 16, 32, 64, and 128 ms. The results showed that late-potential thresholds decreased by an average of 24 dB for 1000-Hz conditions and 18 dB for 4000-Hz conditions. Behavioral thresholds also improved by about 22 dB and 18 dB for 1000-Hz and 4000-Hz conditions, respectively. The slope of improvement for both late-potential and behavioral thresholds was on the order of –4 to –6 dB per doubling of stimulus duration, depending on stimulus frequency. Stimulus duration also influenced latency and amplitude measures of the N1 and P2 components such that response latency decreased and amplitude increased as stimulus duration increased. The present results demonstrate a time-intensity trading relationship in components of the late potentials that is consistent with previous psychophysical and physiological data.
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Rossi, Giovanni, Paolo Solero, and M. Rolando. "Relationships between acoustic reflex patterns elicited by unfiltered white noise and narrow band white noise stimuli of different duration but of the same intensity." Journal of Laryngology & Otology 99, no. 9 (1985): 857–63. http://dx.doi.org/10.1017/s0022215100097814.
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AbstractFor the purpose of this study, acoustic signals were generated by an Amplaid MK VI. An Amplaid 702 impedence meter was connected to its averaging section and to its computer. The stimuli were bursts of unfiltered white noise (UWN) and of narrow band white noise (NBWN; 30 db./oct/slope; central frequencies 1,000, 2,000, 4,000 Hz.) lasting 3–1,000 msec, at intensity of 105 db. SPL p.e. The following parameters were evaluated: stapedius contraction latency, amplitude, duration and recruitment time. It was found that latency was independent of the spectrum of the stimulus and its duration. Amplitude and recruitment time, on the other hand, were related to spectrum and duration, while duration of contraction was directly related to the duration of the stimulus only.
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Wilczynski, Walter, Michael P. Black, Scarlett J. Salem, and Chisom B. Ezeoke. "Behavioural persistence during an agonistic encounter differentiates winners from losers in green anole lizards." Behaviour 152, no. 5 (2015): 563–91. http://dx.doi.org/10.1163/1568539x-00003243.
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Agonistic encounters featuring ritualized displays precede the establishment of dominance relationships in many animals. We investigated the predictive value of the amount of display behaviour (number and duration of displays) vs. quickness to display (latency to express a display behaviour) in determining the outcome of aggressive interactions and establishment of dominant vs. subordinate status in male green anole lizards, Anolis carolinensis. Similar-sized males were paired and observed for ninety minutes as they established social status. We recorded the number, duration (where appropriate) and latencies to first expression for multiple behavioural display components (head bob A, B and C, dewlap displays, open mouth displays, pushups, lateral displays) and colour changes (eyespot presence and body colour changes). Males that eventually won and became the dominant male had significantly higher counts and durations with the exception of Bob C counts, pushup counts and open mouth duration. Future dominants also maintained a green body colour longer than future subordinates, which had brown shades more often and for longer durations. Latency to first express a display component was shorter in future dominants for head bobs A and C, dewlap and open mouth displays when all data were considered. However, all significant latency differences disappeared when data only from pairs in which both males displayed a behaviour were included in the analysis. Counts, durations, and latencies were highly correlated with each other within individuals. The results indicate that behavioural display patterns during an initial display contest predict the outcome of the interaction, with the amount of display behaviour being the best predictor of whether a male will win or lose the contest and hence become dominant or subordinate. These results are consistent with the idea that displays are honest signals of a male’s physiological capacity or stamina, and hence fighting and resource holding ability.
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Tsutsui, Yukako, and Katsuhisa Sunada. "Dexmedetomidine Increases the Latency of Thermal Antinociception in Rats." Anesthesia Progress 64, no. 4 (2017): 230–34. http://dx.doi.org/10.2344/anpr-65-01-08.
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Recent reports have stated that dexmedetomidine (DEX), an α2-adrenoreceptor agonist, enhances the local anesthetic effects of ropivacaine and prolongs its effective duration. However, little is known about the effect of a combination of DEX and lidocaine on anesthetic duration. Therefore, we investigated whether DEX can prolong the local anesthetic effect of lidocaine, using the thermal paw withdrawal test in Wistar rats in order to measure local anesthetic duration. We subcutaneously injected 50 μL of either normal saline, 2% lidocaine, a combination of 0.5 μg/kg DEX and 2% lidocaine, or a combination of 2% lidocaine with 1:80,000 epinephrine into the plantar surface of the left hind paw of the rats. The plantar region was stimulated using heat. We measured the perceived acute pain according to paw movement in response to stimulation. We found DEX significantly prolonged the paw withdrawal latency of lidocaine. Moreover, we found that DEX can prolong the local anesthetic duration of lidocaine as much as 1:80,000 epinephrine, up to 35 minutes after injection. In conclusion, this study concluded that a combination of DEX and lidocaine may be useful as a local anesthetic, similar to a combination of epinephrine and lidocaine, for short procedures.
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Jensen, Megan E., Peter G. Gibson, Clare E. Collins, Jodi M. Hilton, Fiona Latham-Smith, and Lisa G. Wood. "Increased sleep latency and reduced sleep duration in children with asthma." Sleep and Breathing 17, no. 1 (2012): 281–87. http://dx.doi.org/10.1007/s11325-012-0687-1.
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Bloomfield, S. A., and S. M. Sherman. "Postsynaptic potentials recorded in neurons of the cat's lateral geniculate nucleus following electrical stimulation of the optic chiasm." Journal of Neurophysiology 60, no. 6 (1988): 1924–45. http://dx.doi.org/10.1152/jn.1988.60.6.1924.
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1. We recorded intracellularly from X and Y cells of the cat's lateral geniculate nucleus and measured the postsynaptic potentials (PSPs) evoked from electrical stimulation of the optic chiasm. We used an in vivo preparation and computer averaged the PSPs to enhance their signal-to-noise ratio. 2. The vast majority (46 of 50) of our sample of X and Y cells responded to stimulation of the optic chiasm with an excitatory postsynaptic potential (EPSP) followed by an inhibitory postsynaptic potential (IPSP); these were tentatively identified as relay cells. We quantified several parameters of these PSPs, including amplitude, latency, time to peak (i.e., rise time), and duration. 3. Among the relay cells, the latencies of both the EPSP and action potential evoked by optic chiasm stimulation were shorter in Y cells than in X cells. Furthermore, the difference between the latencies of the EPSP and action potential was shorter for Y cells than for X cells. This means that the EPSPs generated in Y cells reached threshold for generation of action potentials faster than did those in X cells. The EPSPs of Y cells also displayed larger amplitudes and faster rise times than did those in X cells, but neither of these distinctions was sufficient to explain the shorter latency difference between the EPSP and action potential for Y cells. 4. The EPSPs recorded in relay Y cells had longer durations than did those in relay X cells. Our data suggest that the subsequent IPSP actively terminates the EPSP, which, in turn, suggests that the time interval between EPSP and IPSP onsets is longer in Y cells than in X cells. Furthermore, we found that, for individual Y cells, the latency and duration of the evoked EPSP were inversely related. These observations lead to the conclusion that the latency of IPSPs activated from the optic chiasm is relatively constant among Y cells and thus independent of the EPSP latencies. Thus the excitation and inhibition produced in individual geniculate Y cells may originate from different populations of retinogeniculate axons. 5. The IPSPs recorded in geniculate relay cells following optic chiasm stimulation could be divided into three groups based on their durations. The majority of both X and Y cells showed short-duration IPSPs, whereas the remainder of Y cells displayed medium-duration IPSPs, and the remaining X cells displayed long-duration IPSPs. A positive correlation was seen between the time to peak and duration of these IPSPs.(ABSTRACT TRUNCATED AT 400 WORDS)
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Balta, Ozgur, Gulten Sungur, Mehmet Yakin, Nurten Unlu, Oyku Bezen Balta, and Firdevs Ornek. "Pattern Visual Evoked Potential Changes in Diabetic Patients without Retinopathy." Journal of Ophthalmology 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/8597629.
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Purpose.To assess the different check sizes of pattern visual evoked potential (PVEP) in diabetic patients without retinopathy according to HbA1c levels and diabetes duration.Methods.Fifty-eight eligible patients with type 2 diabetes mellitus and 26 age- and sex-matched healthy controls were included in the study. Only the right eye of each patient was analyzed. All of the patients underwent a comprehensive ophthalmic examination, and the PVEPs were recorded.Results.There was a statistically significant difference in P100 latency in 1-degree check size and in N135 latency in 2-degree check size between controls and patient groups which have different HbA1c levels. There were statistically significant, positive, and weak correlations with diabetes duration and P100 latency in 7-minute and 15-minute check sizes and N135 latency in 15-minute check size.Conclusions.It was showed that there were prolongations in P100 latency only in 1-degree check size and in N135 only in 2-degree check size in diabetic patients without retinopathy. There was statistically significant correlation between diabetes duration and P100 and N135 latencies in different check sizes.
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Bart, Robert D., Seiji Takaoka, Robert D. Pearlstein, Franklin Dexter, and David S. Warner. "Interactions between Hypothermia and the Latency to Ischemic Depolarization." Anesthesiology 88, no. 5 (1998): 1266–73. http://dx.doi.org/10.1097/00000542-199805000-00018.
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Background The authors postulated that hypothermic neuroprotection can be attributed to a delayed onset of ischemic depolarization. Methods Halothane-anesthetized rats were prepared for near-complete forebrain ischemia. Direct current (DC) potential microelectrodes were placed in hippocampal CA1. The pericranial temperature was maintained at 31 degrees C, 33 degrees C, 35 degrees C, or 37 degrees C (n = 6 per group). Bilateral carotid occlusion with systemic hypotension was initiated for 10 min. The time to onset of the DC shift was recorded. In a second experiment, rats were assigned to 37 degrees C or 31 degrees C for 10 min of ischemia, or to 31 degrees C for 14 min of ischemia (n = 8 per group). These durations of ischemia were defined to allow 9 min of ischemic depolarization in the 37 degrees C-10 min and 31 degrees C-14 min groups. Neurologic and histologic outcomes were examined 7 days later. Results Hippocampal CA1 time to depolarization increased with decreasing temperature (P &lt; 0.0001). Time to depolarization was increased by approximately 4 min in the rats maintained at 31 degrees C compared with those at 37 degrees C. Time to repolarization during reperfusion was not affected by temperature. Increasing the duration of ischemia from 10 min to 14 min with the pericranial temperature maintained at 31 degrees C resulted in a duration of depolarization that was equivalent in the 37 degrees C-10 min and 31 degrees C-14 min groups. However, hippocampal CA1 damage was not increased (31 degrees C-10 min = 4 +/- 1% dead neurons; 31 degrees C-14 min = 6 +/- 1% dead neurons, 95% CI, -1% to 3%; 37 degrees C-10 min = 90 +/- 17% dead neurons). Conclusions Despite similar durations of DC depolarization, outcome in hypothermic rats was markedly improved compared with normothermic rats. This indicates that hypothermic neuroprotection can be attributed to mechanisms other than the delay in time to onset of ischemic depolarization.
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Newhard, William, Munjal Patel, Jason Cassaday, et al. "In Vitro Pharmacokinetic/Pharmacodynamic Modeling of HIV Latency Reversal by Novel HDAC Inhibitors Using an Automated Platform." SLAS DISCOVERY: Advancing the Science of Drug Discovery 26, no. 5 (2021): 642–54. http://dx.doi.org/10.1177/2472555220983810.
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Antiretroviral therapy is able to effectively control but not eradicate HIV infection, which can persist, leading to the need for lifelong therapy. The existence of latently HIV-infected cells is a major barrier to the eradication of chronic HIV infection. Histone deacetylase inhibitors (HDACis), small molecules licensed for oncology indications, have shown the ability to produce HIV transcripts in vitro and in vivo. The pharmacologic parameters that drive optimal HIV latency reversal in vivo are unknown and could be influenced by such factors as the HDACi binding kinetics, concentration of compound, and duration of exposure. This study evaluates how these parameters affect HIV latency reversal for a series of novel HDACis that differ in their enzymatic on and off rates. Varying cellular exposure, using automated washout methods of HDACi in a Jurkat cell model of HIV latency, led to the investigation of the relationship between pharmacokinetic (PK) properties, target engagement (TE), and pharmacodynamic (PD) responses. Using an automated robotic platform enabled miniaturization of a suspension cell-based washout assay that required multiple manipulations over the 48 h duration of the assay. Quantification of histone acetylation (TE) revealed that HDACis showed early peaks and differences in the durability of response between different investigated HDACis. By expanding the sample times, the shift between TE and PD, as measured by green fluorescent protein, could be fully characterized. The comprehensive data set generated by automating the assays described here was used to establish a PK/PD model for HDACi-induced HIV latency reversal.
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Krauzlis, R. J., and F. A. Miles. "Release of fixation for pursuit and saccades in humans: evidence for shared inputs acting on different neural substrates." Journal of Neurophysiology 76, no. 5 (1996): 2822–33. http://dx.doi.org/10.1152/jn.1996.76.5.2822.
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1. In three human subjects, we measured the latency of pursuit and saccadic eye movements made to an eccentric target after a fixated central target was extinguished. In one set of experiments, we varied the time interval between the extinction of the central target and the appearance of the eccentric target (“gap duration”). In a second set of experiments, we varied the eccentricity at which the second target appeared. 2. Varying the gap duration produced similar changes in the latencies of pursuit and saccades. Gaps as short as 30 ms caused significant decreases in latency; progressively longer gaps produced shorter latencies, reaching a minimum for gaps of 150–200 ms. Over the range of gap durations used, the latencies of pursuit and saccades displayed the same dependence on gap duration. 3. Varying the eccentricity of the second target produced different effects on the latencies of pursuit and saccades. Saccade latencies increased when the eccentricity of the second target was decreased from 4 degrees to 0.5 degree, whereas pursuit latencies were not consistently altered. Despite these differences in the dependence on retinal eccentricity between pursuit and saccades, imposing a 200-ms gap between the extinction of the fixation point and appearance of the second target still reduced the latency of both. 4. Our results are consistent with the idea that the mechanisms underlying the release of fixation for pursuit and saccades have shared inputs but a different neural substrate. The common dependence on gap duration may indicate that a single preparatory input coordinates both types of movements. The different dependence on retinal eccentricity indicates that there are differences in the spatial organization of the premotor circuits that trigger the onset of the two types of movements.
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GABEL, S. F., H. MISSLISCH, S. J. SCHAAFSMA, and J. DUYSENS. "Temporal properties of optic flow responses in the ventral intraparietal area." Visual Neuroscience 19, no. 3 (2002): 381–88. http://dx.doi.org/10.1017/s095252380219314x.
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The ventral intraparietal area (VIP) is located at the end of the dorsal stream. Its neurons are known to have receptive-field characteristics similar to those of MT and MST neurons, but little is known about the temporal characteristics of VIP cells' responses. How fast are directionally selective responses evoked in the ventral intraparietal area after viewing optic flow patterns, and what are the temporal properties of these neuronal responses? To examine these questions, we recorded the activity of 37 directionally selective ventral intraparietal area (VIP) neurons in two awake macaque monkeys in response to optic flow stimuli with presentation times ranging from 17 ms to 2000 ms. We found a minimum response latency of 45 ms, and a median latency of 152 ms. Of all neurons, 10% showed early response components only (response latency < 150 ms and no activity in 500–2000 ms interval after stimulus onset), 55% only late response components (response latency >150 ms and sustained activity in 500–2000 ms interval), and 35% both early and late response components. Early responses appeared to very brief stimulus presentations (33-ms duration), while the late responses required longer stimulus durations. The directional selectivity was independent of optic flow duration in all cells. These results suggest that only a subset of neurons in area VIP may contribute to the fast processing of optic flow, while showing that the temporal properties of VIP responses clearly differ from the temporal characteristics of neurons in areas MT and MST.
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Ignatova, Irina I., Paulus Saari, and Roman V. Frolov. "Latency of phototransduction limits transfer of higher-frequency signals in cockroach photoreceptors." Journal of Neurophysiology 123, no. 1 (2020): 120–33. http://dx.doi.org/10.1152/jn.00365.2019.
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Visual transduction in rhabdomeric photoreceptors is compartmentalized and discretized. Signals of individual microvilli, the quantum bumps, are electrotonically summed, producing a graded response. Intrinsic dispersion of quantum bump latencies is thought to introduce noise and degrade signal transfer. Here, we found profound differences in the information rate and signaling bandwidth between in vitro patch-clamp and in vivo intracellular recordings of Periplaneta americana photoreceptors and traced them to the properties of quantum bumps and membrane resistance. Comparison of macroscopic and elementary light responses revealed differences in quantum bump summation and membrane resistance in vivo versus in vitro. Modeling of voltage bumps suggested that current bumps in vivo should be much bigger and faster than those actually recorded in vitro. Importantly, the group-average latency of dark-adapted photoreceptors was 30 ± 8 ms in intracellular ( n = 34) versus 70 ± 19 ms in patch-clamp ( n = 57) recordings. Duration of composite responses increased with mean latency because bump dispersion depended on mean latency. In vivo, latency dispersion broadened the composite response by 25% on average and slowed its onset. However, in the majority of photoreceptors, the characteristic durations of multiphoton impulse responses to 1-ms stimuli did not exceed the durations of mean voltage bumps. Consistently, we found strong associations between the latency and onset kinetics of the macroscopic response, on the one hand and the higher-frequency signal gain and information rate of the photoreceptor, on the other hand, indicating a direct connection between quantum bump latency and its dispersion and the signaling bandwidth. NEW & NOTEWORTHY When stimulated by light, microvilli of rhabdomeric photoreceptors produce discrete signals characterized by variable latencies. We show that this intrinsic latency dispersion restricts signaling bandwidth and information rate of photoreceptors in Periplaneta americana. Profound differences are found between the properties of photoreceptor responses in vivo and in vitro.
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Dupont, G., M. J. Berridge, and A. Goldbeter. "Latency correlates with period in a model for signal-induced Ca2+ oscillations based on Ca2(+)-induced Ca2+ release." Cell Regulation 1, no. 11 (1990): 853–61. http://dx.doi.org/10.1091/mbc.1.11.853.
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Oscillations in cytosolic Ca2+ develop in a variety of cells after an induction phase, called latency, the duration of which depends on the magnitude of external stimulation. Experiments in hepatocytes indicate that the period and latency of Ca2+ oscillations both decrease as the level of the stimulus increases. We analyze the correlation between period and latency in a model recently proposed for signal-induced Ca2+ oscillations. We show that the linear relationship between period and latency observed in the experiments arises naturally in this model as a result of the mechanism of Ca2(+)-induced Ca2+ release on which it is based.
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Abizadeh, Marzieh, Soomaayeh Heysieattalab, Negin Saeedi, et al. "Ameliorating Effects of Dorema ammoniacum on PTZ-Induced Seizures and Epileptiform Brain Activity in Rats." Planta Medica 86, no. 18 (2020): 1353–62. http://dx.doi.org/10.1055/a-1229-4436.
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AbstractThe objective of the current study was to investigate the anti-epileptogenic and anticonvulsant effects of Dorema ammoniacum gum, which is used in Iranian traditional medicine for the treatment of seizures. Animals received pentylenetetrazol (IP, 30 mg/kg/48 h) for inducing seizures. Five different seizure stages were evaluated for 20 min and parameters including maximum seizure stage, the latency to the onset of stage 4, stage 4 duration, and seizure duration were measured. D. ammoniacum (50 and 100 mg/kg) or its vehicle was administered 30 min before or after pentylenetetrazol injection in different groups. In addition, the effective dose of D. ammoniacum (100 mg/kg) on different seizure stages was compared with the common antiseizure drug phenobarbital. In another set of experiments, we investigated the effective dose of D. ammoniacum on fully kindled animals in which an interictal electroencephalogram was recorded by superficial electrodes placed on the skull. The results showed that D. ammoniacum administration, before and after pentylenetetrazol injections, significantly decreased seizure stage, seizure duration, stage 4 duration, and 1/stage 4 latency. The anti-epileptogenic effect of D. ammoniacum was about 50 to 60% of phenobarbital. In addition, D. ammoniacum significantly decreased seizure stage, seizure duration, stage 4 duration, and 1/stage 4 latency when administered to fully kindled animals but had no effect on the power of EEG sub-bands. These results indicate that D. ammoniacum has anti-epileptogenic and anticonvulsant effects in a chemical kindling model of seizures.
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Waters, Thaddeus, Matthew Hoffman, and Anthony Sciscione. "Duration of latency in twin pregnancies with preterm premature rupture of membranes." American Journal of Obstetrics and Gynecology 191, no. 6 (2004): S116. http://dx.doi.org/10.1016/j.ajog.2004.10.302.
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Rotenberg, V. S., P. Indurski, L. Kayumov, and A. Elizur. "472 REM sleep latency depends on wakefulness duration in the 1st cycle." International Journal of Psychophysiology 30, no. 1-2 (1998): 182. http://dx.doi.org/10.1016/s0167-8760(98)90471-8.
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Mogyoros, Ilona, Matthew C. Kiernan, Jean-Michel Gracies, and David Burke. "The effect of stimulus duration on the latency of submaximal nerve volleys." Muscle & Nerve 19, no. 10 (1996): 1354–56. http://dx.doi.org/10.1002/(sici)1097-4598(199610)19:10<1354::aid-mus18>3.0.co;2-u.
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Holick, Crystal N., Edward L. Giovannucci, Bernard Rosner, Meir J. Stampfer, and Dominique S. Michaud. "Prospective study of cigarette smoking and adult glioma: Dosage, duration, and latency." Neuro-Oncology 9, no. 3 (2007): 326–34. http://dx.doi.org/10.1215/15228517-2007-005.
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Wolpaw, Jonathan R., and Xiang Yang Chen. "Operant conditioning of rat H-reflex: effects on mean latency and duration." Experimental Brain Research 136, no. 2 (2001): 274–79. http://dx.doi.org/10.1007/s002210000609.
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Astana, Suhendra, Sriyono, and Joni Haryanto. "Morning Walking and Sleep Disorders in the Elderly." Journal of Computational and Theoretical Nanoscience 17, no. 7 (2020): 2989–92. http://dx.doi.org/10.1166/jctn.2020.9122.
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One of the main aspects of improving health for the elderly is the maintenance of sleep to ensure recovery of bodily functions to an optimal functional level. The elderly will experience physical, psychosocial and spiritual changes with age. One of those changes is the change in sleep quality. Changes in sleep quality is one of the problems caused by the degeneration process in the elderly. Determining the effect of morning walking on the latency and duration of sleep in the elderly. This type of research is a “pre-experiment” research with one group pre-post-test design research design. A total of 20 study subjects carried out walking interventions in the morning as far as 1,800 meters. Before the intervention is pre-tested, then the walking exercise intervention was carried out 5 times a week in the range of 07.00 am-08.00 am. It was observed and accompanied by researchers together with the research team. The intervention was carried out for 2 weeks and continued with a post-test given to respondents to determine the latency and duration of sleep by asking respondents to return the questionnaire filled out by researchers. The results of the latency variable before the intervention were dominated by less categories i.e., 50% but after the intervention the good category increased by 25% the statistical test results showed a p value of 0.001. Sleep duration which was initially dominated by bad category, after intervention the good category became 10% and has a p value of 0.002. Morning walking exercise influences the latency and duration of sleep in the elderly.
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Yetkin, Esat, Kemal Tekin, Hasan Kiziltoprak, Mehmet Ali Sekeroglu, Veysel Cankurtaran, and Hakan Halit Yasar. "Evaluation of static and dynamic pupil characteristics in hyperopic anisometropic amblyopia." European Journal of Ophthalmology 29, no. 5 (2018): 486–93. http://dx.doi.org/10.1177/1120672118803514.
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Purpose:The aim of this study is to perform a comparison of static and dynamic pupillometry measurements in patients with hyperopic anisometropic amblyopia and age-matched controls.Methods:This prospective cross-sectional study consisted of 38 patients with hyperopic anisometropic amblyopia and 80 control subjects. A quantitative pupillometry system was used to evaluate the pupil characteristics of higher hyperopic eyes (Group 1), the fellow eyes (Group 2), and healthy eyes (Group 3). Static pupillometry measurements were taken including scotopic pupil diameter, mesopic pupil diameter, low-photopic pupil diameter, and high-photopic pupil diameter. Subsequently, dynamic pupillometry measurements were taken including resting diameter, amplitude of pupil contraction, latency of pupil contraction, duration of pupil contraction, velocity of pupil contraction, latency of pupil dilation, duration of pupil dilation, and velocity of pupil dilation.Results:Groups 1 and 2 had statistically significantly lower scotopic and high-photopic pupil diameter values compared with Group 3 (p < 0.05). The amplitude of pupil contraction values were also statistically significantly lower in Groups 1 and 2 compared with Group 3 (p = 0.001 and p = 0.003). However, there were no significant differences between the study and the control eyes with respect to mesopic and high-photopic pupil diameter, resting diameter, latency of pupil contraction, duration of pupil contraction, velocity of pupil contraction, latency of pupil dilation, duration of pupil dilation, and velocity of pupil dilation values (p > 0.05, for all).Conclusion:Static and dynamic pupil characteristics of higher hyperopic eyes and their fellow eyes are similar. This may support that amblyopia is not a monocular disorder, but can affect both eyes.
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LeMoine, Felicia, Robert C. Moore, Andrew Chapple, Ferney A. Moore, and Elizabeth Sutton. "Neonatal Survivability following Previable PPROM after Hospital Readmission for Intervention." American Journal of Perinatology Reports 10, no. 04 (2020): e395-e402. http://dx.doi.org/10.1055/s-0040-1721421.
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Abstract Objective To describe our hospital's experience following expectant management of previable preterm prelabor rupture of membranes (pPPROM). Study Design Retrospective review of neonatal survival and maternal and neonatal outcomes of pPPROM cases between 2012 and 2019 at a tertiary referral center in South Central Louisiana. Regression analyses were performed to identify predictors of neonatal survival. Results Of 81 cases of pPPROM prior to 23 weeks gestational age (WGA), 23 survived to neonatal intensive care unit discharge (28.3%) with gestational age at rupture ranging from 180/7 to 226/7 WGA. Increased latency (adjusted odds ratio [aOR] = 1.30, 95% confidence interval [CI] = 1.11, 1.52) and increased gestational age at rupture (aOR = 1.62, 95% CI = 1.19, 2.21) increased the probability of neonatal survival. Antibiotics prior to delivery were associated with increased latency duration (adjusted hazard ratio = 0.55, 95% CI = 0.42, 0.74). Conclusion Neonatal survival rate following pPPROM was 28.3%. Later gestational age at membrane rupture and increased latency periods are associated with increased neonatal survivability. Antibiotic administration following pPPROM increased latency duration.
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Fisicaro, Francesco, Giuseppe Lanza, Carmela Cinzia D’Agate, et al. "Intracortical and Intercortical Motor Disinhibition to Transcranial Magnetic Stimulation in Newly Diagnosed Celiac Disease Patients." Nutrients 13, no. 5 (2021): 1530. http://dx.doi.org/10.3390/nu13051530.
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Background: Celiac disease (CD) may present or be complicated by neurological and neuropsychiatric manifestations. Transcranial magnetic stimulation (TMS) probes brain excitability non-invasively, also preclinically. We previously demonstrated an intracortical motor disinhibition and hyperfacilitation in de novo CD patients, which revert back after a long-term gluten-free diet (GFD). In this cross-sectional study, we explored the interhemispheric excitability by transcallosal inhibition, which has never been investigated in CD. Methods: A total of 15 right-handed de novo, neurologically asymptomatic, CD patients and 15 age-matched healthy controls were screened for cognitive and depressive symptoms to the Montreal Cognitive Assessment (MoCA) and the 17-item Hamilton Depression Rating Scale (HDRS), respectively. TMS consisted of resting motor threshold, amplitude, latency, and duration of the motor evoked potentials, duration and latency of the contralateral silent period (cSP). Transcallosal inhibition was evaluated as duration and latency of the ipsilateral silent period (iSP). Results: MoCA and HDRS scored significantly worse in patients. The iSP and cSP were significantly shorter in duration in patients, with a positive correlation between the MoCA and iSP. Conclusions: An intracortical and interhemispheric motor disinhibition was observed in CD, suggesting the involvement of GABA-mediated cortical and callosal circuitries. Further studies correlating clinical, TMS, and neuroimaging data are needed.
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Krauzlis, R. J., and F. A. Miles. "Initiation of saccades during fixation or pursuit: evidence in humans for a single mechanism." Journal of Neurophysiology 76, no. 6 (1996): 4175–79. http://dx.doi.org/10.1152/jn.1996.76.6.4175.
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1. In four human subjects, we measured the latency of saccadic eye movements made to a second, eccentric target after an initial, foveated target was extinguished. In separate interleaved trails, the targets were either both stationary (“fixation”) or both moving with the same velocity (“pursuit”). For both fixation and pursuit trials, we extinguished the first target at randomized times during maintained fixation or pursuit and varied the time interval (“gap duration”) before the appearance of the second target. 2. During both fixation and pursuit, the presence of a 200-ms gap reduced the latencies of saccades, compared with those obtained with no gap. For two subjects, we imposed additional, intermediate gap durations and found that saccade latencies varied as a function of gap duration. Furthermore, the latencies of saccades elicited during pursuit displayed the same dependence on gap duration as those elicited during fixation. 3. Our results demonstrate that the “gap effect” observed for saccades made during fixation also occurs for saccades made during pursuit. To the extent that the gap effect on saccade latency reflects a mechanism underlying the release of fixation, our results suggest that the same mechanism is invoked for saccades made during pursuit. From the viewpoint of initiating saccades, the existence of separate fixation and pursuit systems may be irrelevant.
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Dell’Osso, Bernardo, Beatrice Benatti, Lucio Oldani, Gregorio Spagnolin, and A. Carlo Altamura. "Differences in duration of untreated illness, duration, and severity of illness among clinical phenotypes of obsessive-compulsive disorder." CNS Spectrums 20, no. 5 (2014): 474–78. http://dx.doi.org/10.1017/s1092852914000339.
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IntroductionObsessive-compulsive disorder (OCD) is a prevalent, disabling, and comorbid condition that is frequently under-recognized and poorly treated. OCD phenotypes may differ in terms of clinical presentation and severity. However, few studies have investigated whether clinical phenotypes differ in terms of latency to treatment (ie, duration of untreated illness[DUI]), duration, and severity of illness. The present study was aimed to quantify the aforementioned variables in a sample of OCD patients.MethodsOne hundred fourteen outpatients with a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) diagnosis of OCD were recruited, and their main clinical features were collected. Severity of illness was assessed through the Yale–Brown Obsessive Compulsive Scale (Y-BOCS), and the main phenotypes were identified through the Y-BOCS Symptom Checklist. A one-way analysis of variance (ANOVA) test, followed by a Bonferroni post-hoc test, were performed to compare DUI, duration, and severity of illness across subgroups.ResultsIn the whole sample, the mean DUI exceeded 7 years (87.35±11.75 months), accounting for approximately half of the mean duration of illness (172.2±13.36 months). When subjects were categorized into 4 main clinical phenotypes, respectively, aggressive/checking (n=31), contamination/cleaning (n=37), symmetry/ordering (n=32), and multiple phenotypes (n=14), DUI, duration, and severity of illness resulted significantly higher in the aggressive/checking subgroup, compared to other subgroups (F=3.58, p<0.01; F=3.07, p<0.01; F=4.390, p<0.01).DiscussionIn a sample of OCD patients, along with a mean latency to treatment of approximately 7 years, regardless of the phenotype, patients had spent half of their duration of illness (DI) without being treated. DUI, duration, and severity of illness resulted significantly higher in the aggressive/checking subgroup.
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Cheng, Fan-Yin, and Craig A. Champlin. "Auditory Brainstem Responses to Successive Sounds: Effects of Gap Duration and Depth." Audiology Research 11, no. 1 (2021): 38–46. http://dx.doi.org/10.3390/audiolres11010005.
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Temporal acuity is the ability to differentiate between sounds based on fluctuations in the waveform envelope. The proximity of successive sounds and background noise diminishes the ability to track rapid changes between consecutive sounds. We determined whether a physiological correlate of temporal acuity is also affected by these factors. We recorded the auditory brainstem response (ABR) from human listeners using a harmonic complex (S1) followed by a brief tone burst (S2) with the latter serving as the evoking signal. The duration and depth of the silent gap between S1 and S2 were manipulated, and the peak latency and amplitude of wave V were measured. The latency of the responses decreased significantly as the duration or depth of the gap increased. The amplitude of the responses was not affected by the duration or depth of the gap. These findings suggest that changing the physical parameters of the gap affects the auditory system’s ability to encode successive sounds.
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Chukwurah, Queendaleen C., and M. Pia Chaparro. "DOES PARTICIPATING IN SUPPLEMENTAL NUTRITION ASSISTANCE PROGRAM IMPROVE THE SLEEP OF OLDER ADULTS?" Innovation in Aging 3, Supplement_1 (2019): S146. http://dx.doi.org/10.1093/geroni/igz038.526.
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Abstract Food insecurity among lower income adults is associated with adverse health outcomes including sleep disorders. Using data from the National Health and Nutrition Examination Survey (NHANES), 2005-2008, we explored the association between participation in the Supplemental Nutrition Assistance Program (SNAP), a safety net program addressing food insecurity, and sleep outcomes among older adults. Total sleep duration (&lt;7 hours inadequate sleep, ≥7 hours adequate sleep) and sleep latency (10-20 mins normal sleep latency, ≤ 9 mins and ≥ 21mins abnormal sleep latency) were available for 805 participants 50 years and older and eligible for SNAP participation (≤130% federal poverty level). SNAP participation (yes/no) was assessed for the previous year. Sleep inadequacy was higher among SNAP participants (46.5%) compared to SNAP-eligible non-participants (36.3%), whereas the corresponding numbers for abnormal sleep latency were 71.8% and 64.1%. Binary logistic regression analysis showed no significant association between SNAP participation and inadequate sleep duration (OR=1.19, 95% CI 0.84-1.70) after adjusting for age, gender, race/ethnicity, education, and food security status. SNAP participation was also not associated with abnormal sleep latency (adjusted OR=1.49, 95% CI 1.00-2.23). SNAP participation was not protective against poor sleep outcomes among a sample of low-income, at risk of food insecurity older adults.
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Deepak, Dessai Teja, Jayashree S. Bhat, and Kaushlendra Kumar. "Ocular Vestibular Evoked Myogenic Potential Using Different Test Stimuli." ISRN Otolaryngology 2013 (August 6, 2013): 1–4. http://dx.doi.org/10.1155/2013/161937.
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Aim. Ocular Evoked Myogenic Potential (oVEMP) are short latency potentials evoked by higher acoustic stimulation. In this study, we aimed at comparing the click, 500 Hz mixed modulated, and 500 Hz short duration tone burst stimuli using oVEMP. Material. Click, 500 Hz mixed modulated and 500 Hz short duration tone burst stimuli were used for the study. Method. Conventional sampling and conveneint study design were used. Sixty healthy subjects underwent contralateral oVEMP testing maintaining 30 degrees upward gaze. Single channel electrode montage was applied to record oVEMP response. Results. On statistical analysis the three stimuli evoked equal response rates (100%), and when latency of n1 and p1 and peak-peak amplitude were compared, the click evoked showed significantly early latency and lower peak-peak amplitude than the 500 Hz stimuli. Five hundred Hz stimuli did not show significant difference in latency and peak-peak amplitude of n1-p1. Discussion. Thus, 500 Hz stimuli can evoke better latency and peak-peak amplitude. oVEMP has good clinical significance in diagnosing subjects with vestibular dysfunction. To add to the sensitivity of the oVEMP test, 500 Hz stimuli may also be used as it can evoke better oVEMP responses in clinical population with good morphology.
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Alluri, Rishi K., Gary J. Rose, Jessica L. Hanson, et al. "Phasic, suprathreshold excitation and sustained inhibition underlie neuronal selectivity for short-duration sounds." Proceedings of the National Academy of Sciences 113, no. 13 (2016): E1927—E1935. http://dx.doi.org/10.1073/pnas.1520971113.
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Sound duration is important in acoustic communication, including speech recognition in humans. Although duration-selective auditory neurons have been found, the underlying mechanisms are unclear. To investigate these mechanisms we combined in vivo whole-cell patch recordings from midbrain neurons, extraction of excitatory and inhibitory conductances, and focal pharmacological manipulations. We show that selectivity for short-duration stimuli results from integration of short-latency, sustained inhibition with delayed, phasic excitation; active membrane properties appeared to amplify responses to effective stimuli. Blocking GABAA receptors attenuated stimulus-related inhibition, revealed suprathreshold excitation at all stimulus durations, and decreased short-pass selectivity without changing resting potentials. Blocking AMPA and NMDA receptors to attenuate excitation confirmed that inhibition tracks stimulus duration and revealed no evidence of postinhibitory rebound depolarization inherent to coincidence models of duration selectivity. These results strongly support an anticoincidence mechanism of short-pass selectivity, wherein inhibition and suprathreshold excitation show greatest temporal overlap for long duration stimuli.
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Shirai, Nobu, Takeharu Seno, and Sachie Morohashi. "More Rapid and Stronger Vection in Elementary School Children Compared with Adults." Perception 41, no. 11 (2012): 1399–402. http://dx.doi.org/10.1068/p7251.
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We compared vection (visually induced illusory self-motion perception) among elementary school children and adults by measuring latency to onset, cumulative duration, and estimated strength of vection. Significantly stronger vection with shorter latency was observed in children compared with adults. Several possible causes (eg size-difference of the effective visual field) of the age-related differences are discussed.
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Kapoula, Zoï. "Differential Impact Of Sound On Saccades Vergence And Combined Eye Movements: A Multiple Case Study." Journal of Clinical Studies and Medical Case Reports 5, no. 3 (2020): 1–9. http://dx.doi.org/10.24966/csmc-8801/100095.
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Most of the previous literature regarding eye movements use visual stimuli alone. However, in real life, visual and auditory stimuli occur together frequently. It has been shown that a sound presented just before or simultaneously with the visual target reduces the latency of the saccades. The present study investigates the effect of a sound presented shortly before the LED visual target for three types of eye movements: saccades, vergences and combined eye movements. Fourteen participants (6 women, mean age: 22.6 +/- 0.62 years) took part in the study. Each type of eye movements was tested in two conditions: one with visual LED targets alone, the other with a sound coming for a buzzer adjacent to the LED, and preceding by 50 ms the onset of the LED target (auditory-visual target). Eye movements were recorded at 220 Hz for each eye with the Eyeseecam binocular devicehttps://www.eyeseetec.de/eyeseecam-sci/). The results confirm that the sound significantly reduces the latency of the saccades. In contrast, for convergence or divergence the sound did not decrease the latency but it did increase the velocity and reduced the duration of such movements significantly. For combined saccade vergence movements particularly leftward, the sound had multiple effects on the saccade component: it decreased the duration of the saccade component and reciprocally increased its velocity but also reduced its latency. Such mixed effects on latency duration and velocity of the saccade component favor the hypothesis that saccade components of combined eye movements are subtended by a co-activation of both, saccade and vergence brainstem generators. The differential benefit from the sound according to the type of eye movements is of theoretical and clinical interest.
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Kombos, Theodoros, Olaf Suess, Öczan Ciklatekerlio, and Mario Brock. "Monitoring of intraoperative motor evoked potentials to increase the safety of surgery in and around the motor cortex." Journal of Neurosurgery 95, no. 4 (2001): 608–14. http://dx.doi.org/10.3171/jns.2001.95.4.0608.
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Object. The repetitive application of high-frequency anodal monopolar stimulation during surgery in or near the motor cortex allows a qualitative and quantitative evaluation of motor evoked potentials (MEPs). Using this method, motor pathways and motor function can be continuously monitored during surgery. Methods. In this prospective study, 70 patients underwent MEP monitoring during surgery performed in the central region. All procedures were performed after general anesthesia had been induced without the aid of muscle relaxants. The motor pathways were monitored during the entire surgical procedure by repetitive high-frequency anodal monopolar stimulation (frequency 400–500 Hz; train 7–10 pulses; impulse duration 0.2–0.7 msec; and stimulation intensity 16.9 ± 7.76 mA). The MEPs were continuously evaluated to assess their latency, potential duration, and amplitude. Recorded alterations in these parameters were subsequently correlated with surgical maneuvers and with postoperative neurological deterioration. The monitoring parameters (latency, potential duration, and amplitude) had a broad interindividual range of variation. A correlation between individual intraoperative changes in the potentials and surgical maneuvers or postoperative neurological deterioration was observed in eight cases. A spontaneous shift in latency greater than 15% or a sudden reduction in the amplitude of the potential greater than 80% was considered a warning criterion. In all cases in which there was an irreversible change in latency or a complete loss of potentials were observed, there was postoperative neurological deterioration. Conclusions. Improved surgical safety can be achieved using intraoperative neurophysiological monitoring procedures. Repetitive stimulation of the motor cortex proved to be a reliable method for monitoring subcortical motor pathways. Changes in MEP latency and MEP amplitude served as warning criteria during surgery and possessed prognostic value.
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Smith, P. M., and A. V. Ferguson. "Paraventricular nucleus efferents influence area postrema neurons." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 270, no. 2 (1996): R342—R347. http://dx.doi.org/10.1152/ajpregu.1996.270.2.r342.
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Extracellular single-unit recordings were obtained from area postrema neurons (AP), and peristimulus histograms were used to determine the effects of paraventricular nucleus (PVN) stimulation on these cells from anesthetized Sprague-Dawley rats. Of 91 AP cells tested, 30.8% responded to PVN stimulation with a short-latency (28.2 +/- 3.3 ms, mean +/- SE), short-duration (49.3 +/- 8.0 ms) excitation, whereas 8.6% were inhibited. In animals that had stimulation sites outside of PVN (non-PVN), only 4 of the 72 AP cells tested (5.6%) were influenced by stimulation. These excitatory effects of PVN stimulation on AP neurons were unaffected by V1-receptor blockade. Of 93 nucleus of the solitary tract (NTS) cells tested, 38.9% responded to PVN stimulation with a short-latency (18.5 +/- 2.4 ms), short-duration (48.8 +/- 9.6 ms) excitation and 22.2% with short-latency (20.75 +/- 4.1 ms), long-duration (204.4 +/- 44.9 ms) inhibitions. In contrast, non-PVN stimulation sites influenced only 19% of NTS neurons tested, all of which were excited. These data demonstrate that activation of PVN neurons elicits excitatory effects on the majority of AP neurons influenced. They further emphasize the potential significance of descending hypothalamic inputs in controlling neuronal activity in this circumventricular organ.
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Alcántara, Carmela, and Sarah Diaz. "779 Effects of lifetime trauma exposure on the association between neighborhood safety and sleep." Sleep 44, Supplement_2 (2021): A303. http://dx.doi.org/10.1093/sleep/zsab072.776.
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Abstract Introduction Greater perceived neighborhood safety (PNS) has been linked to better sleep quality and longer sleep duration. There is also evidence that past exposure to traumatic events may be associated with lower perceived personal safety and poor mental health. Yet, the moderating effects of lifetime trauma exposure on the association between PNS and sleep (duration & latency), has not been assessed. Methods We used cross-sectional data from 190 healthy NYC Latino adults. Lifetime trauma exposure was measured using the Life Events Checklist [LEC] (a count of traumatic events that happened to or were witnessed). In the first set of models, we regressed self-reported sleep duration in minutes (continuous), on PNS (safe vs. not safe), a single item scale, with three covariates (i.e. age, gender, education). In the second set, self-reported sleep latency in minutes, replaced sleep duration. To test for moderation, interaction terms—LEC x PNS—were added to covariate-adjusted models. In sensitivity analyses, regression models were re-run with adjustment for PTSD symptoms, and with short sleep duration (&lt;7hours) as the outcome. Results On average, participants were 37.9 years old (SE= 1.02), 65.8% female, 59.5% foreign-born, and 33.2% completed &lt; Bachelor’s degree. Overall, 43.68% slept &lt;7 hours and 83.68% were exposed to &gt;1 traumatic event in their lifetime. In adjusted models, each traumatic event (b= -2.95, SE = 1.34, p=0.03) was negatively associated with sleep duration. When PTSD symptoms was added, trauma was no longer statistically significant (b=-1.08, SE=1.02, p=0.18). However, each traumatic event exposure was associated with a 10% higher odds of short sleep duration (OR= 1.10, CI=1.02, 1.15), and this association remained significant with adjustment for PTSD symptoms. No interaction terms were significant. In models for sleep latency, there were no statistically significant main effects for LEC or interaction terms. Conclusion We found a dose response in the negative association between lifetime exposure to trauma and sleep duration, but not sleep latency. Trauma history did not moderate the association between PNS and sleep. These results suggest that short sleep duration may be particularly sensitive to lifetime exposure to trauma independent of neighborhood safety. Future studies should replicate these results in population-based samples. Support (if any):