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We present the pulse arrival times and high-precision dispersion measure estimates for 14 millisecond pulsars observed simultaneously in the 300
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500 MHz and 1260
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1460 MHz frequency bands using the upgraded Giant Metrewave Radio Telescope. The data spans over a baseline of 3.5 years (2018-2021), and is the first official data release made available by the Indian Pulsar Timing Array collaboration. This data release presents a unique opportunity for investigating the interstellar medium effects at low radio frequencies and their impact on the timing precision of pulsar timing array experiments. In addition to the dispersion measure time series and pulse arrival times obtained using both narrowband and wideband timing techniques, we also present the dispersion measure structure function analysis for selected pulsars. Our ongoing investigations regarding the frequency dependence of dispersion measures have been discussed. Based on the preliminary analysis for five millisecond pulsars, we do not find any conclusive evidence of chromaticity in dispersion measures. Data from regular simultaneous two-frequency observations are presented for the first time in this work. This distinctive feature leads us to the highest precision dispersion measure estimates obtained so far for a subset of our sample. Simultaneous multi-band upgraded Giant Metrewave Radio Telescope observations in 300
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500 MHz and 1260
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1460 MHz are crucial for high-precision dispersion measure estimation and for the prospect of expanding the overall frequency coverage upon the combination of data from the various Pulsar Timing Array consortia in the near future. Parts of the data presented in this work are expected to be incorporated into the upcoming third data release of the International Pulsar Timing Array.
First responders to disasters are at risk of developing post-traumatic stress disorder (PTSD). The trajectories of post-traumatic stress symptom severity differ among individuals, even if they are exposed to similar events. These trajectories have not yet been reported in non-Western first responders.
Objectives
We aimed to explore post-traumatic stress symptom severity trajectories and their risk factors in first responders to the 2011 Great East Japan Earthquake (GEJE)— a historically large earthquake that resulted in a tsunami and a nuclear disaster.
Methods
56 388 Japan Ground Self-Defense Force (JGSDF) personnel dispatched to the GEJE were enrolled in this seven-year longitudinal cohort study. PTSD symptom severity was measured using the Impact of Event Scale-Revised (IES-R). Trajectories were identified using latent growth mixture models (LGMM). Nine potential risk factors for the symptom severity trajectories were analyzed using multinomial logistic regression.
Results
Five symptom severity trajectories were identified: “resilient” (54.7%), “recovery” (24.5%), “incomplete recovery” (10.7%), “late-onset” (5.7%), and “chronic” (4.3%). The main risk factors for the four non-resilient trajectories were older age, personal disaster experiences, and working conditions. These working conditions included duties involving body recovery or radiation exposure risk, longer deployment length, later or no post-deployment leave, and longer post-deployment overtime.
Conclusions
The majority of first responders to GEJE were resilient and developed few or no PTSD symptoms. A substantial minority experienced late-onset and chronic symptom severity trajectories. The identified risk factors can inform policies for prevention, early detection, and intervention in individuals at risk of developing symptomatic trajectories.
Precise instrumental calibration is of crucial importance to 21-cm cosmology experiments. The Murchison Widefield Array’s (MWA) Phase II compact configuration offers us opportunities for both redundant calibration and sky-based calibration algorithms; using the two in tandem is a potential approach to mitigate calibration errors caused by inaccurate sky models. The MWA Epoch of Reionization (EoR) experiment targets three patches of the sky (dubbed EoR0, EoR1, and EoR2) with deep observations. Previous work in Li et al. (2018) and (2019) studied the effect of tandem calibration on the EoR0 field and found that it yielded no significant improvement in the power spectrum (PS) over sky-based calibration alone. In this work, we apply similar techniques to the EoR1 field and find a distinct result: the improvements in the PS from tandem calibration are significant. To understand this result, we analyse both the calibration solutions themselves and the effects on the PS over three nights of EoR1 observations. We conclude that the presence of the bright radio galaxy Fornax A in EoR1 degrades the performance of sky-based calibration, which in turn enables redundant calibration to have a larger impact. These results suggest that redundant calibration can indeed mitigate some level of model incompleteness error.
Recent research on Flight-deck Interval Management (FIM), a modern technology for increasing safety and improving airspace and runway utilisation through self-spacing, has led to the development of a new rule-based logic for FIM, namely Interval Management – Speed Planning (IM-SP). In an initial benchmark study, IM-SP showed good spacing performance with a significant reduction in speed commands, a major area of concern with previous FIM logics, resulting in a lower burden on the flight crew during FIM operation. Nevertheless, there remains scope for improvement in other aspects, such as fuel burn. In this study, the internal cost function of IM-SP is further analysed and optimised using speed-constrained multi-objective particle swarm optimisation to improve the performance of IM-SP under the multiple objectives of FIM. The optimisation renders new settings that address the problem areas, improve the speed commands and enhance the overall quality of IM-SP. Two distinctive solutions, viz. a spacing performance optimised setting and a fuel burn optimised setting, are further analysed and discussed, and directions for follow-up research are explored.
The authors evaluated cerebral blood flow response in schizophrenia patients during face perception to test the hypothesis of diminished limbic activation related to emotional relevance of facial stimuli.
Method
Thirteen patients with schizophrenia and 17 comparison subjects viewed facial displays of happiness, sadness, surprise, anger, fear, and disgust as well as neutral faces using the Japanese and Caucasian Facial Expressions of Emotion and Neutral Faces (Matsumoto and Ekman, 1988). Functional magnetic resonance imaging was used to measure blood-oxygen-level-dependent signal changes as the subjects alternated between tasks of discriminating sex with an interleaved reference condition.
Results
The groups did not differ in performance on the task. Healthy participants showed activation in the bilateral fusiform gyrus, medial temporal structures, occipital lobe, and inferior frontal cortex relative to the baseline condition. The increase was greater these regions in the right hemisphere than those in the left hemisphere. In the patients with schizophrenia, minimal focal response in the right fusiform gyrus, medial temporal structures, and occipital lobe was observed for the facial perception task relative to the baseline condition. Contrasting patients and comparison subjects revealed voxels in the left medial temporal structures, occipital lobe in which the healthy comparison subjects had significantly greater activation.
Conclusions
Impaired activation was seen in patients with schizophrenia for detection of facial attributes such as sex. Impairment in the medial temporal structure such as amygdale may lead to misunderstanding of social communication and may underlie difficulties in social adjustment experienced by people with schizophrenia.
Studies on community-acquired pneumonia (CAP) and pneumococcal pneumonia (PP) related to the 13-valent pneumococcal conjugate vaccine (PCV13) introduction in Asia are scarce. This study aimed to investigate the epidemiological and microbiological determinants of hospitalised CAP and PP after PCV13 was introduced in Japan. This observational hospital-based surveillance study included children aged ⩽15 years, admitted to hospitals in and around Chiba City, Japan. Participants had bacterial pneumonia based on a positive blood or sputum culture for bacterial pathogens. Serotype and antibiotic-susceptibility testing of Streptococcus pneumoniae and Haemophilus influenzae isolates from patients with bacterial pneumonia were assessed. The CAP hospitalisation rate per 1000 child-years was 17.7, 14.3 and 9.7 in children aged <5 years and 1.18, 2.64 and 0.69 in children aged 5–15 years in 2008, 2012 and 2018, respectively. There was a 45% and 41% reduction in CAP hospitalisation rates, between the pre-PCV7 and PCV13 periods, respectively. Significant reductions occurred in the proportion of CAP due to PP and PCV13 serotypes. Conversely, no change occurred in the proportion of CAP caused by H. influenzae. The incidence of hospitalised CAP in children aged ⩽15 years was significantly reduced after the introduction of PCV13 in Japan. Continuous surveillance is necessary to detect emerging PP serotypes.
Although longitudinal magnetic resonance imaging (MRI) studies have shown that various brain regions undergo progressive tissue loss during the early phases of schizophrenia, regional pattern of these changes remain unclear.
Methods
Longitudinal MRI data were obtained from 18 (12 males and 6 females) patients with first-episode schizophrenia and 20 (11 males and 9 females) healthy controls and at baseline and follow-up with mean scan interval of 2.7 years. To compare gray matter changes over time between patients and controls were evaluated with voxel-based morphometry (VBM) using SPM8 following the longitudinal DARTEL protocol.
Results
In both groups of patient and control longitudinal gray mater reduction was observed in various brain regions including lateral and medial frontal regions and superior temporal region. Excessive decrease in gray matter was found in patients as compared to healthy controls in the left superior temporal region and right inferior frontal region.
Discussion
Our findings suggest that there are differing longitudinal gray matter changes in patients with schizophrenia during the early phases of the illness as compared to healthy individuals.
The primary goal of this study is to examine the effectiveness of a community-based multimodal intervention program for suicide prevention in regions where the suicide rate was relatively high compared to control regions. The secondary goal was to explore the effectiveness of a community-based multimodal intervention program for suicide prevention in highly populated regions.
Methods/design:
NOCOMIT-J is a community-based large-scale non-randomized controlled trial, involving seven intervention regions with accompanying control regions, all with populations of statistically sufficient size. The program consists of
1) Establishing social support networks in the public health system for suicide prevention and mental health promotion;
2) A primary prevention measures of awareness campaign for the public and key personnel;
3) Secondary prevention measures for screening, counseling and outreach services for high-risk individuals;
4) After-care for individuals bereaved by suicide;
5) Suicide prevention measures especially for individuals with mental illness and work-related problems.
This study protocol was reviewed and approved by the Central Ethics Committee of the J-MISP. Additionally, the regional leaders obtained written authorization from the local governors.
Results/progress:
The intervention started in July 2006, and continued for 3.5 years. Participants are Japanese and foreign residents living in the intervention and control regions, a total of population of 2,120,000 individuals.
Discussion:
Because treatment and prevention of suicide are complex and encompass many factors, success will need multi-sector collaboration. We hope that the results of NOCOMIT-J will help to develop effective strategies to reduce future suicide rate. (ClinicalTrials.gov: NCT00737165)
Reduced white matter integrity in the corpus callosum (CC) has been reported in treatment-resistant depression (TRD). rTMS is assumed to have remote effect on interconnected area with the stimulation site, and this effect is speculated to be one of the therapeutic mechanisms of rTMS treatment. In this preliminary study, we examined changes of callosal fiber integrity in 5 segments of the CC before and after rTMS treatment for TRD.
Methods:
The subjects were 2 patients with treatment-resistant unipolar depression and 1 patient with treatment-resistant bipolar depression, and 24 healthy controls (HC group). The patients underwent 4-week high frequency rTMS to their left DLPFC. In diffusion tensor imaging (DTI) tractography, the CC was divided into 5 segments (orbital, frontal, parietal, temporal, and occipital) based on their cortical projection zones, and fractional anisotropy (FA) value of each segment was estimated. We compared FA in the CC between the patients and the HC groups, and examined changes of FA in the CC after rTMS treatment in the patients.
Results:
The patients showed reduced FA in the frontal, parietal, temporal, and occipital-callosal segments compared to the HC group. All patients responded to the rTMS treatment, and FA in the orbital, frontal, parietal, temporal-callosal segments increased after the rTMS treatment.
Conclusions:
Our results suggest that white matter integrity in the CC is reduced in TRD and that increased white matter integrity in the CC might be related with the therapeutic mechanisms of rTMS treatment.
Impaired self-awareness has been noted as a core feature of schizophrenia. Recent neuroimaging studies examining self-referential process in schizophrenia have yielded inconsistent results. We aimed to examine the self-referential neural network using the self- and other-evaluation tasks in schizophrenia.
Methods
Fifteen schizophrenia patients and fifteen age-, sex- and parental education-matched healthy subjects underwent functional magnetic resonance imaging. Subjects were required to make a decision whether the sentence described their own personal trait (self-evaluation) and that of their close friends (other-evaluation).
Results
Both patients and healthy groups showed significant activation in multiple brain regions including the medial- and lateral-prefrontal, temporal and parietal cortices during self- and other-evaluation tasks. The control subjects showed higher activations in left posterior cingulate and parahippocampal gyri during self-evaluation than other-evaluation, whereas there was no difference in activated regions between self- and other-conditions in the patients. As compared with the controls, the patients showed higher activations in the right superior frontal and right supramarginal gyri during self-evaluation.
Conclusions
These findings provide evidence for neural basis for deficits in self-awareness in schizophrenia and may underlie core clinical symptomatology of schizophrenia.
A history of previous suicide attempt is a potent risk factor for suicide later on. Crisis intervention initiated at emergency medical facilities for suicide attempters are considered important components for suicide prevention. The primary aim of this trial is to examine the effectiveness of an extensive intervention for suicide attempters in prevention of recurrent suicidal behavior, as compared with standard intervention.
Methods/design
ACTION-J is a single blinded randomized controlled trial. In this trial, case management intervention were provided at 19 emergency medical facilities in Japan. After psychiatric evaluation and psychological education, subjects were randomly assigned to either a group receiving continuous case management or standard care. Suicidal ideation, depressive symptoms, and general health condition were evaluated as secondary measures. The stratified logrank test based on allocation factors will be performed for all eligible participants in the intent-to-treat analysis. The study protocol was reviewed and approved by the Central Ethics Committee of the J-MISP. The protocol was also reviewed and approved by the On-site Research Ethics Committee at each participating hospital.
Results/progress
The intervention was initiated in July 2006. By December 2009, 914 subjects were randomized. Subject follow-up continued for 1.5 to 5 years, till the end of June 2011. ACTION-J would provide valuable information on suicide attempters and may develop effective case management to reduce future risk for suicide attempters. (ClinicalTrials.gov: NCT00736918.)
In bipolar disorder (BD), reduced white matter (WM) integrity in the corpus callosum has been reported, but its detailed localization difference has not been clarified. In this study, we examined fiber integrity in 7 segments of the corpus callosum and their relationships with clinical symptoms in BD.
Methods:
Patients with BD (BD group, n = 17) and age-matched healthy controls (HC group, n = 24) were examined using diffusion tensor imaging tractography. The corpus callosum was divided into 7 segments (orbital frontal, anterior frontal, superior frontal, superior parietal, posterior parietal, temporal, and occipital) based on their cortical projection zones, and fractional anisotropy (FA) value of each segment was estimated. Differences in FA of each segment between the groups were examined using ANOVA with repeated measures. Correlations between FA of each segment and clinical symptoms (HAM-D, YMRS) were assessed using Spearman's rank correlation test in the BD group.
Results:
The BD group showed reduced FA in the orbital frontal, superior frontal, and posterior parietal-callosal segments compared to the HC group. In addition, the BD group showed a significant negative correlation between FA in the orbital frontal-callosal segment and HAM-D scores.
Conclusions:
Our results suggest that WM integrity in the anterior part of the corpus callosum is reduced in BD and that orbital frontal-callosal disintegrity may be related with severity of bipolar depression.
In January 2012, an inpatient in a ward of a psychiatric hospital with nearly 300 beds in Kanagawa, Japan, was diagnosed with sputum smear-positive pulmonary tuberculosis (TB). Here we characterise the TB outbreak cases and identify the population at risk. TB was diagnosed when a person tested bacteriologically positive for TB or was determined to have TB by a physician. A latent TB infection (LTBI) case was defined as a person tested positive by interferon-gamma release assay (IGRA). A total of 125 contacts were screened via IGRA and chest X-ray. In all, 15 TB and 15 LTBI cases were found by the end of October 2012, and thereafter no additional TB case was found. Of the 15 TB cases, eight were culture-positive and all the isolates had identical variable number tandem repeat patterns. Twenty-four of the 56 (42.9%, 95% confidence interval (CI) 29.7–56.8) inpatients in the ward had either TB or LTBI with a relative risk of 8.6 (95% CI 1.2–59.3), compared to the staff members who did not work full-time in the ward (one of 20 (5.0%, 95% CI 0.0–24.9)). We recommend that psychiatric hospitals conduct periodic screening of staff members and inpatients for TB to prevent nosocomial TB outbreaks.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together
$60+$
programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
Disturbed sleep and activity are prominent features of bipolar disorder type I (BP-I). However, the relationship of sleep and activity characteristics to brain structure and behavior in euthymic BP-I patients and their non-BP-I relatives is unknown. Additionally, underlying genetic relationships between these traits have not been investigated.
Methods
Relationships between sleep and activity phenotypes, assessed using actigraphy, with structural neuroimaging (brain) and cognitive and temperament (behavior) phenotypes were investigated in 558 euthymic individuals from multi-generational pedigrees including at least one member with BP-I. Genetic correlations between actigraphy-brain and actigraphy-behavior associations were assessed, and bivariate linkage analysis was conducted for trait pairs with evidence of shared genetic influences.
Results
More physical activity and longer awake time were significantly associated with increased brain volumes and cortical thickness, better performance on neurocognitive measures of long-term memory and executive function, and less extreme scores on measures of temperament (impulsivity, cyclothymia). These associations did not differ between BP-I patients and their non-BP-I relatives. For nine activity-brain or activity-behavior pairs there was evidence for shared genetic influence (genetic correlations); of these pairs, a suggestive bivariate quantitative trait locus on chromosome 7 for wake duration and verbal working memory was identified.
Conclusions
Our findings indicate that increased physical activity and more adequate sleep are associated with increased brain size, better cognitive function and more stable temperament in BP-I patients and their non-BP-I relatives. Additionally, we found evidence for pleiotropy of several actigraphy-behavior and actigraphy-brain phenotypes, suggesting a shared genetic basis for these traits.
Flight-deck Interval Management (FIM) is a modern airborne self-spacing technology that improves arrival route throughput and runway utilisation and increases hourly arrival capacity by up to four aircraft per hour and per runway, compared to conventional air traffic controller guided arrivals. The National Aeronautics and Space Administration (NASA) has been the leader in FIM research and formulated a logic that was put to an actual flight test in 2017. Despite the overall success of the project, operational deficiencies concerning the number of speed commands, which led to several recommendations for future research before operational implementation, were discovered. In this study, a new logic that implements a two-stage rule-based selection algorithm was developed to overcome those deficiencies. The proposed logic was compared to NASA’s logic on an arrival in Tokyo International Airport with multiple induced error patterns. The results indicate that the new logic significantly decreases the number of speed commands with only minor aggravations in spacing performance. The results that highlight the strengths and weaknesses of both concepts are discussed, and an outlook on and ideas for future research on FIM and the proposed logic are presented.
We studied a suitable procedure for preparing of water samples used in radiocarbon intercomparisons involving dissolved inorganic carbon (DIC). The water samples must have inter-batch consistency and stable 14C concentrations and no sterilizing agent (e.g., HgCl2) should be added, in order to avoid the production of hazardous material. Six water samples, containing widely different amounts and types of salts, DIC, and 14C concentrations (1–100 pMC), were prepared in order to assess the procedure. Sample consistency was investigated through δ13C and chemical compositions; their low variabilities indicate that our procedure can be applied to radiocarbon intercomparison. A specific sample preparation protocol was developed for this kind of applications.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
In November 2016, a woman in her 30s who stayed at an insecure, temporary housing facility, a manga café in Tokyo, Japan, for a year was diagnosed with sputum smear-positive tuberculosis (TB). Since the café had 31 staff members and provided with accommodation to many people, the local health office initiated a contact investigation. This study aims to characterise the cases found in the outbreak. A TB case was defined as a person tested bacteriologically positive for TB, or was determined to have TB by a physician. A latent TB infection case was defined as a person tested positive by interferon-γ release assay. From January 2016 through November 2017, there were 31 staff members at the manga café, of which, six developed TB disease (one smear-negative, culture-positive and five smear- and culture-negative) in addition to seven LTBI. Another long-term customer was found having sputum smear-positive TB. Variable numbers tandem repeat (VNTR) test revealed that the index patient and the long-term customer had the identical type of VNTR; however, one staff member had a different VNTR. Local health authorities should intensify screening long-term customers of such facilities for TB regularly as well as once a TB outbreak occurs.