35 research outputs found
Power Spectrum Analysis of the OMC1 Image at 1.1 mm Wavelength
We present a 1.1mm emission map of the OMC1 region observed with AzTEC, a new
large-format array composed of 144 silicon-nitride micromesh bolometers, that
was in use at the James Clerk Maxwell Telescope (JCMT). These AzTEC
observations reveal dozens of cloud cores and a tail of filaments in a manner
that is almost identical to the submillimeter continuum emission of the entire
OMC1 region at 450 and 850 micronm. We perform Fourier analysis of the image
with a modified periodogram and the density power spectrum, which provides the
distribution of the length scale of the structures, is determined. The expected
value of the periodogram converges to the resulting power spectrum in the mean
squared sense. The present analysis reveals that the power spectrum steepens at
relatively smaller scales. At larger scales, the spectrum flattens and the
power law becomes shallower. The power spectra of the 1.1mm emission show clear
deviations from a single power law. We find that at least three components of
power law might be fitted to the calculated power spectrum of the 1.1mm
emission. The slope of the best fit power law, \gamma ~ -2.7 is similar to
those values found in numerical simulations. The effects of beam size and the
noise spectrum on the shape and slope of the power spectrum are also included
in the present analysis. The slope of the power law changes significantly at
higher spatial frequency as the beam size increases.Comment: 7 pages, 2 figures, Journal of the Korean Astronomical Society, vol.
45, pp.93-99; For Figure 1, please refer to
http://jkas.kas.org/journals/2012v45n4/v45n4p093_skim.pd
Are You Asking What Time Did Your Patients Go to Bed?: Getting the Short Sleep Onset Latency
A few patients diagnosed with insomnia attempt going to bed earlier to obtain adequate sleep and fall asleep less than 30 min, although they often complain about their inability to fall asleep easily. The aim of this study was to explore the association between short sleep latency and patients’ sleepwake pattern. All the 99 patients with primary insomnia who were under treatment with benzodiazepine or non-benzodiazepine gamma-aminobutyric acid (GABA) agonists as sleeping pills were selected. The time to take hypnotics, bedtime, sleep onset, and wake-up times were determined from medical records. Subjects who showed sleep latency of less than 30 min (SL ≤ 30, n = 56) were treated with hypnotics (10:46 pm) before going to bed (11:00 pm) later compared with subjects with sleep latency greater than 30 min (SL > 30 min, n = 43, hypnotic ingestion time, 9:46 pm; bedtime 10:10 pm). Duration from wake-up time to bedtime (WTB) was significantly longer in SL ≤ 30 group (16.5 ± 1.1 h) compared to SL > 30 group (15.8 ± 1.5 h). Long sleep latency was significantly correlated with old age, earlier ingestion of sleeping pills, earlier bedtime, and short duration of WTB (all, p < 0.01). Early bed time in the evening was not associated with short sleep latency. Patients with insomnia may find that delayed bedtime may promote faster sleep
Gamma Oscillation in Schizophrenia
Dysfunctional neural circuitry has been found to be involved in abnormalities of perception and cognition in patients with schizophrenia. Gamma oscillations are essential for integrating information within neural circuits and have therefore been associated with many perceptual and cognitive processes in healthy human subjects and animals. This review presents an overview of the neural basis of gamma oscillations and the abnormalities in the GABAergic interneuronal system thought to be responsible for gamma-range deficits in schizophrenia. We also review studies of gamma activity in sensory and cognitive processes, including auditory steady state response, attention, object representation, and working memory, in animals, healthy humans and patients with schizophrenia
The Optimizing Strategies for Prescription of Sleeping Pills for Insomnia Patients
Many patients claim that they cannot sleep well despite ingestion of sleeping pills. In such cases, the physician should explore the reason why sleep disturbance persisted in patients despite administration of sleeping pills. We should consider patients’ age, gender, medical or psychiatric diseases, workplace, or sleep environment that may influence patients’ sleep and satisfaction with their hypnotics. However, prior to prescribing a hypnotic agent for patients with sleep disturbance, good sleep hygiene education should be provided first. Cognitive-behavioral therapy for insomnia is an important and effective treatment modality to improve patients’ sleep quality and reduce dosage of sleeping pills, but it is not easy for most general practitioners to learn and practice this modality. Therefore, we need to consider how to optimize the prescription of hypnotics for treating insomnia in order to prescribe hypnotics safely and appropriately at the lowest dosage. Physician should consider the mechanism of action of each hypnotic agent and prescribe proper hypnotics according to patients’ comorbid illness, insomnia types, or other underlying sleep disorders. Also, we should instruct the patients about when they should take their sleeping pills and we should monitor whether they have followed the instructions or not. Hospitalized patients are in a different sleep environment compared to outpatients, and therefore, we should also prepare modified management strategies for inpatients. In this review, strategies for optimizing the prescription of sleeping pills for insomnia patients will be discussed
Assessment of Cancer-Related Dysfunctional Beliefs about Sleep for Evaluating Sleep Disturbance in Cancer Patients
Dysfunctional beliefs about sleep may be associated with chronic sleep disturbance in patients afflicted with cancer over the trajectory of their battle with cancer. The objective of this study was exploration of the utility of assessing the sleep disturbances suffered by cancer patients possibly emanating from two cancer-related informationally valid but nonetheless dysfunctional beliefs: “My immune system will have serious problems if I don’t go to sleep at a certain time (question 1)” and “If I don’t sleep well at night, my cancer can recur or metastasize (question 2).” The scores for these beliefs were significantly correlated with insomnia severity [measured using the Insomnia Severity Index (p < 0.01)] and fear of disease progression [measured using the Fear of Progression Questionnaire (p < 0.01)]. The question 2 score also correlated with younger age (p = 0.01) and high depression scores assessed using the Patient Health Questionnaire-9 (p = 0.04). We believe the scores for these two cancer-related dysfunctional beliefs can be used to help evaluate sleep disturbances in cancer patients
Insomnia and Parental Overprotection are Associated with Academic Stress among Medical Students
Background and Objective The purpose of this study was to explore particular aspects of the mental health status of medical students and to identify relationships among them. Methods All 191 medical students from University of Ulsan College of Medicine were included in this study. Psychological parameters were measured with the Medical Stress Scale (MSS), Insomnia Severity Index, Korean-Parental Overprotection Scale, Patient Health Questionnaire-9 and Academic Motivation Scale. Results Stressed students (MSS ≥ 28) had significantly higher scores on insomnia severity (5.8 ± 4.5 vs 4.4 ± 3.0, p < 0.05), depression (5.7 ± 4.5 vs 2.6 ± 2.4, p < 0.01), and amotivation (9.3 ± 3.3 vs 6.9 ± 2.2, p < 0.01) and lower scores of intrinsic motivation (3.5 ± 7.1 vs. 41.7 ± 7.2, p < 0.01) compared to non-stressed students (MSS < 28). Significant correlations were noted between several factors and Medical Stress Scores. Specifically, insomnia, depression, amotivation and maternal ‘face culture’ of parental overprotection, had independent and significant influences on academic stress reported by medical students (R2 = 0.39, p < 0.01). Conclusions Our findings revealed insomnia, depression, academic motivation and parental overprotection are relevant factors influencing stress in medical students. Current results provide insights for stress management including the importance of parenting intervention
Adapting Cognitive-Behavior Therapy for Insomnia in Cancer Patients
Insomnia disorder is common in patients undergoing cancer treatment. There is compelling evidence demonstrating that cognitive-behavioral therapy for insomnia (CBT-I) should be the initial treatment, but there has been insufficient research has been conducted among cancer patients. This population presents with unique physical and psychosocial health issues that may interfere with standard CBT-I and addressing these issues can play a role in improving treatment adherence and efficacy. We explore potential adaptations that can be made to standard CBT-I for cancer patients. Further research for this growing population is essential
The Effectiveness of Prolonged-Release Melatonin in Primary Insomnia Patients with a Regular Sleep-Wake Cycle
Background and Objective Prolonged-release melatonin (PRM) might effectively increase patient satisfaction when administered to individuals older than 55 years old with primary insomnia who were not satisfied with their sleep even after their sleep-wake cycle schedule was set. We investigated patients’ satisfaction rate with PRM when they took it after their sleep-wake cycle was set. Methods Among 87 patients who were prescribed PRM at the sleep clinic, 44 patients with primary insomnia who complained of poor sleep quality even after adopting a set 7-hour sleep-wake schedule or taking sleeping pills 7 hours before wake-up time were selected their medical records were reviewed. We explored patients’ satisfaction rates with PRM after 3–4 weeks. Results Among the 35 subjects who completed follow-up, 23 (66%) reported an improvement in insomnia symptoms after taking PRM. Five subjects reported daytime sleepiness as treatment-emergent adverse events. Of the 25 subjects taking other sleeping pills at baseline and followed up, 11 (44%) reduced their sleeping pill dosage by at least 50%. Five subjects completely discontinued their previous sleeping pills after starting PRM. Conclusions We observed a high satisfaction rate with PRM when prescribed to patients with a regular sleep-wake cycle. We believe that the results of this study will help to optimize hypnotic prescription to insomnia patients
Insomnia and Neuroticism are Related with Depressive Symptoms of Medical Students
Background and Objective Insomnia is very common in depression and especially medical students are easy to experience sleep disturbance because of their studies. Also depressive symptoms are closely related to stress. Stress is an interaction between an individual and the environment, involving subjective perception and assessment of stressors, thus constituting a highly personalized process. Different personality traits can create different levels of stress. In this study, we tried to explore the relationship between insomnia and depressive symptoms or stress of medical students, and whether their personality may play a role on this relationship or not. Methods We enrolled 154 medical students from University of Ulsan College of Medicine. We used the Medical Stress Scale, the Multidimensional Perfectionism Scale, the Patient Health Questionnaire-9, the Academic Motivation Scale, the Insomnia Severity Index, and The revised NEO Personality Inventory (PI). Results Insomnia severity, amotivation, medical stress, mental health index and neuroticism traits of NEO-PI significantly correlated with depressive symptom severity (p < 0.001). And stepwise linear regression analysis indicated insomnia, amotivation and neuroticism traits of NEO-PI are expecting factors for students’ depressive symptoms is related to (p < 0.001). Conclusions Student who tend to be perfect feel more academic stress. The high level of depressive symptom is associated with insomnia, amotivation, academic stress in medical student. Moreover, personality trait also can influence their depressive symptoms