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Temporal Relation (temporal + relation)
Selected AbstractsAn Empirical and Computational Investigation of Perceiving and Remembering Event Temporal RelationsCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2009Shulan Lu Abstract Events have beginnings, ends, and often overlap in time. A major question is how perceivers come to parse a stream of multimodal information into meaningful units and how different event boundaries may vary event processing. This work investigates the roles of these three types of event boundaries in constructing event temporal relations. Predictions were made based on how people would err according to the beginning state, end state, and overlap heuristic hypotheses. Participants viewed animated events that include all the logical possibilities of event temporal relations, and then made temporal relation judgments. The results showed that people make use of the overlap between events and take into account the ends and beginnings, but they weight ends more than beginnings. Neural network simulations showed a self-organized distinction when learning temporal relations between events with overlap versus those without. [source] Are antidepressants safe in the treatment of bipolar depression?ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2008A critical evaluation of their potential risk to induce switch into mania or cycle acceleration Objective:, To address whether switch of depression into hypomania or mania or cycle acceleration in patients with bipolar disorder is caused by antidepressants or whether this phenomenon is attributable to the natural history of bipolar disorder itself. Method:, A critical review of the literature, pointing at sources of bias that have been previously overlooked. For examining the causation in question, the Bradford,Hill criteria were applied, i.e. specificity of the potential causative agent, strength of effect, consistency in findings, dose,response relation, temporal relation with exposure to agent preceding effect and biological plausibility. Results:, There is a scarcity of randomized studies addressing the question, and the available studies all suffer from various forms of bias. However, there is some evidence suggesting that antidepressants given in addition to a mood stabilizer are not associated with an increased rate of switch when compared with the rate associated with the mood stabilizer alone. Conclusion:, When combined with a mood stabilizer, antidepressants given for acute bipolar depression seemingly do not induce a switch into hypomania or mania. Whether antidepressants may accelerate episode frequency and/or may cause other forms of destabilization in patients with bipolar disorder remain to be properly studied. [source] High-frequency Oscillations after Status Epilepticus: Epileptogenesis and Seizure GenesisEPILEPSIA, Issue 9 2004Anatol Bragin Summary:,Purpose: To investigate the temporal relation between high-frequency oscillations (HFOs) in the dentate gyrus and recurrent spontaneous seizures after intrahippocampal kainite-induced status epilepticus. Methods: Recording microelectrodes were implanted bilaterally in different regions of hippocampus and entorhinal cortex. A guide cannula for microinjection of kainic acid (KA) was implanted above the right posterior CA3 area of hippocampus. After recording baseline electrical activity, KA (0.4 ,g/0.2 ,l) was injected. Beginning on the next day, electrographic activity was recorded with video monitoring for seizures every day for 8 h/day for ,30 days. Results: Of the 26 rats studied, 19 revealed the appearance of sharp-wave activity and HFOs in the frequency range of 80 to 500 Hz in the dentate gyrus ipsilateral to the KA injection. In the remaining seven rats, no appreciable activity was noted in this frequency range. In some rats with recurrent seizures, HFOs were in the ripple frequency range (100,200 Hz); in others, HFOs were in the fast ripple frequency range (200,500 Hz), or a mixture of both oscillation frequencies was found. The time of detection of the first HFOs after status epilepticus varied between 1 and 30 days, with a mean of 6.3 ± 2.0 (SEM). Of the 19 rats in which HFO activity appeared, all later developed recurrent spontaneous seizures, whereas none of the rats without HFOs developed seizures. The sooner HFO activity was detected after status epilepticus, the sooner the first spontaneous seizure occurred. A significant inverse relation was found between the time to the first HFO detection and the subsequent rate of spontaneous seizures. Conclusions: A strong correlation was found between a decreased time to detection of HFOs and an increased rate of spontaneous seizures, as well as with a decrease in the duration of the latent period between KA injection and the detection of spontaneous seizures. Two types of HFOs were found after KA injection, one in the frequency range of 100 to 200 Hz, and the other, in the frequency range of 200 to 500 Hz, and both should be considered pathological, suggesting that both are epileptogenic. [source] Inverted metamorphic sequence in the Sikkim Himalayas: crystallization history, P,T gradient and implicationsJOURNAL OF METAMORPHIC GEOLOGY, Issue 5 2004S. Dasgupta Abstract The metapelitic rocks of the Sikkim Himalayas show an inverted metamorphic sequence (IMS) of the complete Barrovian zones from chlorite to sillimanite + K-feldspar, with the higher grade rocks appearing at progressively higher structural levels. Within the IMS, four groups of major planar structures, S1, S2 and S3 were recognised. The S2 structures are pervasive throughout the Barrovian sequence, and are sub-parallel to the metamorphic isograds. The mineral growth in all zones is dominantly syn-S2. The disposition of the metamorphic zones and structural features show that the zones were folded as a northerly plunging antiform. Significant bulk compositional variation, with consequent changes of mineralogy, occurs even at the scale of a thin section in some garnet zone rocks. The results of detailed petrographic and thermobarometric studies of the metapelites along a roughly E,W transect show progressive increase of both pressure and temperature with increasing structural levels in the entire IMS. This is contrary to all models that call for thermal inversion as a possible reason for the origin of the IMS. Also, the observation of the temporal relation between crystallization and S2 structures is problematic for models of post-/late-metamorphic tectonic inversion by recumbent folding or thrusting. A successful model of the IMS should explain the petrological coherence of the Barrovian zones and the close relationship of crystallization in each zone with S2 planar structures along with the observed trend(s) of P,T variation in Sikkim and in other sections. A discussion is presented of some of the available models that, with some modifications, seem to be capable of explaining these observations. [source] Reduced genital sensitivity in female patients with multiple system atrophy of parkinsonian typeMOVEMENT DISORDERS, Issue 4 2003Wolfgang H. Oertel MD Abstract According to the consensus statement on the diagnosis of multiple system atrophy (MSA), erectile dysfunction is required for male patients to fulfil the urinary incontinence criterion. However, there is no equivalent item for female patients. We questioned 19 female patients with MSA of the parkinsonian type (MSA-P), 28 female patients with Parkinson's disease (PD), and 27 healthy controls on their genital sensitivity. A total of 47% of the MSA patients but only 4% of the PD patients and 4% of the control group admitted to reduced genital sensitivity, a highly significant difference (P < 0.001). Moreover, the appearance of reduced genital sensitivity in female MSA patients showed a close temporal relation to the onset of the disease. If these preliminary results can be confirmed and further specified in a larger sample, a historical item of reduced genital sensitivity in female patients might become a diagnostic feature for MSA, comparable to erectile dysfunction in male patients. © 2002 Movement Disorder Society [source] Visual deprivation increases accumulation of dense core vesicles in developing optic tectal synapses in Xenopus laevisTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 12 2010Jianli Li Abstract Despite considerable progress in understanding the molecular components of synapses in the central nervous system, the ultrastructural rearrangements underlying synaptic development remain unclear. We used serial section transmission electron microscopy and three-dimensional reconstructions of the optic tectal neuropil of Xenopus laevis tadpoles to detect and quantify changes in synaptic ultrastructure over a 1-week period from stages 39 and 47, during which time the visual system of Xenopus tadpoles becomes functional. Synapse density, presynaptic maturation index, and number of synapses per axon bouton increase, whereas the number of DCVs per bouton decreases, between stages 39 and 47. The width of the synaptic cleft decreased and the diameter of postsynaptic profiles increased between stages 39 and 47 and then remained relatively unchanged after stage 47. We found no significant difference in synapse maturation between GABAergic and non-GABAergic synapses. To test the effect of visual experience on synaptogenesis, animals were deprived of visual experience for 3 days from stage 42 to 47. Visual deprivation decreased synapse maturation and the number of connections per bouton. Furthermore, visual deprivation increased the number of DCVs per bouton by more than twofold. The visual-deprivation-induced decrease in synaptic connections is specific to asymmetric non-GABAergic synapses; however, both symmetric GABAergic and asymmetric synapses show comparable increases in the number DCVs with visual deprivation. In both the control and the visually deprived animals, the number of DCVs per bouton is highly variable and does not correlate with either synapse maturation or the number of connected partners per bouton. These data suggest that synaptogenesis and DCV accumulation are regulated by visual experience and further suggest a complex spatial and temporal relation between DCV accumulation and synapse formation. J. Comp. Neurol. 518:2365,2381, 2010. © 2010 Wiley-Liss, Inc. [source] Co-expression of IGF-1 family members with myogenic regulatory factors following acute damaging muscle-lengthening contractions in humansTHE JOURNAL OF PHYSIOLOGY, Issue 22 2008Bryon R. McKay Muscle regeneration following injury is dependent on the ability of muscle satellite cells to activate, proliferate and fuse with damaged fibres. This process is controlled by the myogenic regulatory factors (MRF). Little is known about the temporal relation of the MRF with the expression of known myogenic growth factors (i.e. IGF-1) in humans following muscle damage. Eight subjects (20.6 ± 2.1 years; 81.4 ± 9.8 kg) performed 300 lengthening contractions (180 deg s,1) of their knee extensors in one leg on a dynamometer. Blood and muscle samples were collected before and at 4 (T4), 24 (T24), 72 (T72) and 120 h (T120) post-exercise. Mechano growth factor (MGF), IGF-1Ea and IGF-1Eb mRNA were quantified. Serum IGF-1 did not change over the post-exercise time course. IGF-1Ea and IGF-1Eb mRNA increased ,4- to 6-fold by T72 (P < 0.01) and MGF mRNA expression peaked at T24 (P= 0.005). MyoD mRNA expression increased ,2-fold at T4 (P < 0.05). Myf5 expression peaked at T24 (P < 0.05), while MRF4 and myogenin mRNA expression peaked at T72 (P < 0.05). Myf5 expression strongly correlated with the increase in MGF mRNA (r2= 0.83; P= 0.03), while MRF4 was correlated with both IGF-1Ea and -Eb (r2= 0.90; r2= 0.81, respectively; P < 0.05). Immunofluorescence analysis showed IGF-1 protein expression localized to satellite cells at T24, and to satellite cells and the myofibre at T72 and T120; IGF-1 was not detected at T0 or T4. These results suggest that the temporal response of MGF is probably related to the activation/proliferation phase of the myogenic programme as marked by an increase in both Myf5 and MyoD, while IGF-1Ea and - Eb may be temporally related to differentiation as marked by an increase in MRF4 and myogenin expression following acute muscle damage. [source] Psoriasis and the risk of incident diabetes mellitus: a population-based studyBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2008Y.B. Brauchli Summary Background, Cross-sectional studies, mostly in hospitalized patients, reported a possible positive association between psoriasis and diabetes mellitus (DM). However, information on the temporal relation is scarce, and incidence rates of new-onset DM in patients with psoriasis are lacking. Objectives, To assess and compare incidence rates of new-onset DM between patients with psoriasis and a comparison group without psoriasis, and to explore the role of psoriasis severity and body mass index (BMI). Methods, We conducted a follow-up study with a nested case,control analysis within the U.K.-based General Practice Research Database. The study population consisted of patients with a first-time diagnosis of psoriasis between 1994 and 2005 and a matched group of psoriasis-free patients. We used psoriasis duration and treatment as proxy for disease severity, and we applied conditional logistic regression to obtain odds ratios (ORs) with 95% confidence intervals (CIs). Results, Within the study population of 65 449 patients we identified 1061 incident cases of DM. Of these, 59% had a history of psoriasis, yielding a crude incidence rate ratio of 1·36 (95% CI 1·20,1·53). The adjusted OR for patients with , 2 years disease duration and > 2 prescriptions per year for oral psoriasis treatment was 2·56 (95% CI 1·11,5·92). In an analysis restricted to patients with normal BMI, the adjusted OR was 2·02 (95% CI 1·31,3·10). Conclusions, In this large observational study the risk of incident DM was increased for patients with psoriasis as compared with a psoriasis-free comparison group. The risk increased with psoriasis duration and severity and was not driven by high BMI alone. [source] Onset of Kleine-Levin Syndrome in association with isotretinoin treatmentACTA PAEDIATRICA, Issue 6 2010H Smedje Abstract The synthetic retinoid isotretinoin is an effective treatment option for severe forms of acne vulgaris. However, several reports indicate that some patients experience altered central nervous system functions in association with treatment. We present here the first description of the onset of Kleine-Levin Syndrome (KLS), a rare disorder characterised by periodic hypersomnia and cognitive and behavioural symptoms, in close temporal relation to the start of isotretinoin treatment. We also discuss the biological potential of retinoids to affect sleep. Conclusions:, In light of a documented potential of retinoids to modulate sleep-wake regulation, the present case suggests that isotretinoin may rarely trigger the onset of KLS. [source] Diagnostic testing in suspected fluoroquinolone hypersensitivityCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2009C. S. Seitz Summary Background Because of their broad antibacterial activity in the gram-negative and gram-positive spectrum, high oral bioavailability, and good tissue penetration, fluoroquinolone antibiotics are widely used. Besides direct drug-related side-effects, fluoroquinolones may cause hypersensitivity reactions. Objective The aim of this retrospective analysis was to present the results of diagnostic testing in cases of clinically suspected fluoroquinolone-induced immediate or delayed hypersensitivity. Methods We studied 101 patients with a history of immediate or delayed hypersensitivity symptoms in temporal relation to treatment with a fluoroquinolone antibiotic using standardized skin testing, followed by oral challenges. Patients with anaphylaxis symptoms were further evaluated with in vitro tests. Results Fluoroquinolone hypersensitivity was excluded in 71 patients by tolerated oral challenge tests. During positive challenge tests, six patients (three out of these had positive and three had negative skin prick tests) developed anaphylaxis symptoms but the presumed IgE-mediated mechanism could not be confirmed by in vitro tests. Patch testing was constantly negative; however, in two patients a rash was induced by the challenge tests. Conclusion History alone leads clearly to a considerable over-estimation of fluoroquinolone hypersensitivity. Moreover, skin or in vitro tests do not seem to be very useful in identifying hypersensitive patients. Challenge tests appear to be necessary for definitely confirming or ruling out fluoroquinolone hypersensitivity. [source] The psychophysiology of the maternal,fetal relationshipPSYCHOPHYSIOLOGY, Issue 4 2004Janet A. Dipietro Abstract The enigmatic quality of the maternal,fetal relationship has been extolled throughout history with little empirical support. We apply time series analysis to data for 137 maternal,fetal pairs collected at 20, 24, 28, 32, 36, and 38 weeks gestation. Maternal heart rate and skin conductance data were digitized in tandem with fetal heart rate and motor activity. No temporal relations between fetal heart rate and either maternal variable were found, although averaged maternal and fetal heart rates were correlated from 32 weeks. Consistent temporal associations between fetal movement and maternal heart rate and skin conductance were detected. Fetal movement stimulated rises in each parameter, peaking at 2 and 3 s, respectively. Associations did not change over gestation, were unaffected by a maternal stressor, and showed within-pair stability. The bidirectional nature of the maternal,fetal relationship is considered. [source] Emotion Regulation as a Scientific Construct: Methodological Challenges and Directions for Child Development ResearchCHILD DEVELOPMENT, Issue 2 2004Pamela M. Cole Emotion regulation has emerged as a popular topic, but there is doubt about its viability as a scientific construct. This article identifies conceptual and methodological challenges in this area of study and describes exemplar studies that provide a substantive basis for inferring emotion regulation. On the basis of those studies, 4 methods are described that provide compelling evidence for emotion regulation: independent measurement of activated emotion and purported regulatory processes; analysis of temporal relations; measurement across contrasting conditions; and multiple, convergent measures. By offering this perspective, this article aims to engage thoughtful debate and critical analysis, with the goal of increasing methodological rigor and advancing an understanding of emotion regulation as a scientific construct. [source] An Empirical and Computational Investigation of Perceiving and Remembering Event Temporal RelationsCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2009Shulan Lu Abstract Events have beginnings, ends, and often overlap in time. A major question is how perceivers come to parse a stream of multimodal information into meaningful units and how different event boundaries may vary event processing. This work investigates the roles of these three types of event boundaries in constructing event temporal relations. Predictions were made based on how people would err according to the beginning state, end state, and overlap heuristic hypotheses. Participants viewed animated events that include all the logical possibilities of event temporal relations, and then made temporal relation judgments. The results showed that people make use of the overlap between events and take into account the ends and beginnings, but they weight ends more than beginnings. Neural network simulations showed a self-organized distinction when learning temporal relations between events with overlap versus those without. [source] | ||||||||||||||||