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With wide-field phased array feed technology, the Australian Square Kilometre Array Pathfinder (ASKAP) is ideally suited to search for seemingly rare radio transient sources that are difficult to discover previous-generation narrow-field telescopes. The Commensal Real-time ASKAP Fast Transient (CRAFT) Survey Science Project has developed instrumentation to continuously search for fast radio transients (duration ≲ 1 second) with ASKAP, with a particular focus on finding and localising Fast Radio Bursts (FRBs). Since 2018, the CRAFT survey has been searching for FRBs and other fast transients by incoherently adding the intensities received by individual ASKAP antennas, and then correcting for the impact of frequency dispersion on these short-duration signals in the resultant incoherent sum (ICS) in real-time. This low-latency detection enables the triggering of voltage buffers, which facilitates the localisation of the transient source and the study of spectro-polarimetric properties at high time resolution. Here we report the sample of 43 FRBs discovered in this CRAFT/ICS survey to date. This includes 22 FRBs that had not previously been reported: 16 FRBs localised by ASKAP to. ≲ 1 arcsec and 6 FRBs localised to ∼ 10 arcmin. Of the new arcsecond-localised FRBs, we have identified and characterised host galaxies (and measured redshifts) for 11. The median of all 30 measured host redshifts from the survey to date is z = 0.23. We summarise results from the searches, in particular those contributing to our understanding of the burst progenitors and emission mechanisms, and on the use of bursts as probes of intervening media. We conclude by foreshadowing future FRB surveys with ASKAP using a coherent detection system that is currently being commissioned. This will increase the burst detection rate by a factor of approximately ten and also the distance to which ASKAP can localise FRBs.
Accurate diagnosis of bipolar disorder (BPD) is difficult in clinical practice, with an average delay between symptom onset and diagnosis of about 7 years. A depressive episode often precedes the first manic episode, making it difficult to distinguish BPD from unipolar major depressive disorder (MDD).
Aims
We use genome-wide association analyses (GWAS) to identify differential genetic factors and to develop predictors based on polygenic risk scores (PRS) that may aid early differential diagnosis.
Method
Based on individual genotypes from case–control cohorts of BPD and MDD shared through the Psychiatric Genomics Consortium, we compile case–case–control cohorts, applying a careful quality control procedure. In a resulting cohort of 51 149 individuals (15 532 BPD patients, 12 920 MDD patients and 22 697 controls), we perform a variety of GWAS and PRS analyses.
Results
Although our GWAS is not well powered to identify genome-wide significant loci, we find significant chip heritability and demonstrate the ability of the resulting PRS to distinguish BPD from MDD, including BPD cases with depressive onset (BPD-D). We replicate our PRS findings in an independent Danish cohort (iPSYCH 2015, N = 25 966). We observe strong genetic correlation between our case–case GWAS and that of case–control BPD.
Conclusions
We find that MDD and BPD, including BPD-D are genetically distinct. Our findings support that controls, MDD and BPD patients primarily lie on a continuum of genetic risk. Future studies with larger and richer samples will likely yield a better understanding of these findings and enable the development of better genetic predictors distinguishing BPD and, importantly, BPD-D from MDD.
Centanafadine (CTN) is a potential first-in-class norepinephrine/dopamine/serotonin triple reuptake inhibitor (NDSRI) in development for treatment of attention-deficit/hyperactivity disorder (ADHD). The effect of CTN on cardiac repolarization from a thorough QT (TQT) trial is reported.
Methods
In this double-blind, placebo (PBO)- and active-controlled, 3-period crossover TQT trial, healthy adults (18-65 years) were randomized to dosing sequences including CTN (800 mg supratherapeutic dose: 4 x 100 mg tablets in the morning and 5 hours later), CTN PBO (4 PBO tablets in the morning and 5 hours later), and active control moxifloxacin (400 mg + CTN PBO in the morning and CTN PBO 5 hours later). Morning doses were separated by 72 hours. Plasma was collected and data were extracted from continuously recorded ECGs for 24 hours following dosing. Effects on ECG parameters (QT interval with Fridericia correction factor [QTcF], PR and QRS intervals, and T- and U-wave morphology), and heart rate (HR) were assessed. The primary analysis was C-QTc, the relationship between drug concentration and PBO-corrected change from baseline in QTcF (ΔΔQTcF). Categorical analyses of ECG parameters were conducted for changes in QTcF, PR, and QRS intervals and in HR.
Results
Of 30 participants enrolled, 56.7% were male and 86.7% were White. Mean (SD) age was 37.6 (14.5) years; mean (SD) BMI was 26.4 (3.4) kg/m2. The slope (90% CI) of the C-QTc relationship for CTN was −0.001 (−0.003, 0.00002) msec/[ng/mL] and not significant. The predicted ΔΔQTcF (90% CI) at the geometric mean Cmax of CTN 800 mg was −2.72 (−6.92, 1.48) msec. A significant slope (90% CI) of the C-QTc relationship for moxifloxacin (0.004 [0.002, 0.006] msec/[ng/mL]) and a predicted ΔΔQTcF (90% CI) at the geometric mean Cmax of moxifloxacin 400 mg above 5 msec (11.75 [8.25, 15.24]) confirmed assay sensitivity. No ΔΔQTcF ≥10 msec was observed for CTN at any postdose time point; all upper limits of 90% CIs of ΔΔQTcF were <10 msec. The by-time-point analysis showed the maximum least squares mean difference in ΔQTcF (90% CI) between CTN and PBO was 1.64 (−1.40, 4.68) msec at 24 hours postdose. No CTN-treated participants had a QTcF increase of >30 msec; no relevant increases in PR or QRS interval or HR were observed. Four participants had >25% decrease in HR and <50 beats per minute. No abnormal U waves were observed; 1 participant had abnormal T-wave morphology. No serious TEAEs or deaths were reported. The most frequently reported TEAEs with CTN were nausea (24.1%), dizziness (24.1%), and decreased appetite (13.8%).
Conclusions
In this TQT trial, centanafadine, a potential first-in-class NDSRI in development for treatment of ADHD, had no clinically meaningful effect on cardiac repolarization and was generally safe and well tolerated.
Previous presentation: 2023 ACCP Annual Meeting, September 10–12, 2023, Bellevue, WA
A table of values of Chi-square for two degrees of freedom corresponding to values of P from .001 to .999 is presented, together with a description and an example of its use in combining probabilities from two or more independent samples to obtain an aggregate probability.
The Colorado Immersion Training in Community Engagement (CIT) program supports a change in the research trajectory of junior faculty, early career researchers, and doctoral students toward Community-Based Participatory Research (CBPR). CIT is within the Community Engagement and Health Equity Core (CEHE) at the Colorado Clinical and Translational Sciences Institute (CCTSI), an NIH-funded Clinical and Translational Science award. This Translational Science Case Study reports on CIT’s impacts from 2010 to 2019. A team from The Evaluation Center at the University of Colorado Denver utilized four primary data sources: administrative records, participant written reflections, participant and Community Research Liaison (CRL) interviews, and community partner surveys. Data were analyzed using the framework of CBPR principles and the conceptual logic model. CIT trained 122 researchers in CBPR through embedded education within various Colorado communities. CIT Alumni secured ∼$8,723,000 in funding between CCTSI Pilot Grants and external funding. Also, CIT alumni implemented CBPR into curricula and community programming and developed deep, lasting relationships. Further key learnings include the crucial role of CRLs in building relationships between university and community partners and how CIT may serve as a mechanism to improve historical mistrust between communities and universities.
Objectives: Understanding how the importance of modifiable risk factors for dementia varies by cognitive status and sex is vital for the development of effective approaches to dementia prevention. We aimed to calculate population attributable fractions (PAFs) for incident dementia associated with sets of risk factors while exploring sex differences in individuals who are cognitively normal (CN) or has mild cognitive impairment (MCI).
Methods: Longitudinal data from the Rush University Memory and Aging Project (MAP) were analysed. Included participants were aged over 50 years and were CN or with a diagnosis of MCI at their baseline assessment. Analyses considered fifteen potential dementia risk factors covering cardiometabolic, lifestyle, psychosocial and sensory domains. We used Cox proportional hazard models to estimate the hazard ratios for incident dementia associated with dementia risk factors and calculated weighted PAFs. All analyses were repeated stratified by sex.
Results: The analytical sample comprised 754 cognitively normal participants (77.2% female) and 242 participants with a diagnosis of MCI (71.9% female), of whom 214 (28.4%) and 120 (49.6%) were diagnosed with dementia across the follow-up, respectively. Although the weighted overall PAF was similar for CN (24.7%) and MCI (25.2%) subgroups, sex differences were present in both. Compared to in females, PAFs were higher in males in both CN (42.5% vs. 25.1%) and MCI (51.6% vs 12.3%) subgroups. The profiles of contributing risk factors also varied by sex. In males, the highest PAFs were smoking (11.1%), vision impairment (6.2%) and stroke (6.0%) in CN and smoking (13.3%), physical inactivity (12.9%) and heart attack (7.9%) in MCI. In females, the highest PAFs were unmarried marital status (4.9%), depression (4.1%) and social isolation (3.8%) in CN and vision impairment (4.4%), increased alcohol intake (3.5%) and depression (2.6%) in MCI.
Conclusions: These findings support the notion that dementia risk is modifiable after the onset of MCI. They also highlight the potential benefits of considering an individual’s cognitive status and sex when formulating dementia prevention strategies.
It is well established that there is a substantial genetic component to eating disorders (EDs). Polygenic risk scores (PRSs) can be used to quantify cumulative genetic risk for a trait at an individual level. Recent studies suggest PRSs for anorexia nervosa (AN) may also predict risk for other disordered eating behaviors, but no study has examined if PRS for AN can predict disordered eating as a global continuous measure. This study aimed to investigate whether PRS for AN predicted overall levels of disordered eating, or specific lifetime disordered eating behaviors, in an Australian adolescent female population.
Methods
PRSs were calculated based on summary statistics from the largest Psychiatric Genomics Consortium AN genome-wide association study to date. Analyses were performed using genome-wide complex trait analysis to test the associations between AN PRS and disordered eating global scores, avoidance of eating, objective bulimic episodes, self-induced vomiting, and driven exercise in a sample of Australian adolescent female twins recruited from the Australian Twin Registry (N = 383).
Results
After applying the false-discovery rate correction, the AN PRS was significantly associated with all disordered eating outcomes.
Conclusions
Findings suggest shared genetic etiology across disordered eating presentations and provide insight into the utility of AN PRS for predicting disordered eating behaviors in the general population. In the future, PRSs for EDs may have clinical utility in early disordered eating risk identification, prevention, and intervention.
Disordered eating (DE) is associated with elevated cardiometabolic risk (CMR) factors, yet little is known about this association in non-Western countries. We examined the association between DE characteristics and CMR and tested the potential mediating role of BMI. This cross-sectional study included 2005 Chinese women (aged 18–50 years) from the 2015 China Health and Nutrition Survey. Loss of control, restraint, shape concern and weight concern were assessed using selected questions from the SCOFF questionnaire and the Eating Disorder Examination-Questionnaire. Eight CMR were measured by trained staff. Generalised linear models examined associations between DE characteristics with CMR accounting for dependencies between individuals in the same household. We tested whether BMI potentially mediated significant associations using structural equation modelling. Shape concern was associated with systolic blood pressure (β (95 % CI) 0·06 (0·01, 0·10)), diastolic blood pressure (DBP) (0·07 (95 % CI 0·03, 0·11)) and high-density lipoprotein (HDL)-cholesterol (–0·08 (95 % CI –0·12, −0·04)). Weight concern was associated with DBP (0·06 (95 % CI 0·02, 0·10)), triglyceride (0·06 (95 % CI 0·02, 0·10)) and HDL-cholesterol (–0·10 (95 % CI –0·14, −0·07)). Higher scores on DE characteristics were associated with higher BMI, and higher BMI was further associated with lower HDL-cholesterol and higher other CMR. In summary, we observed significant associations between shape and weight concerns with some CMR in Chinese women, and these associations were potentially partially mediated by BMI. Our findings suggest that prevention and intervention strategies focusing on addressing DE could potentially help reduce the burden of CMR in China, possibly through controlling BMI.
In this study, we examined the impact of the number and type of arterial grafts, and surgical dressing type, on deep and organ/space surgical site infection following coronary artery bypass graft procedures. Bilateral internal mammary artery grafts and negative pressure wound therapy were associated with higher odds of infection.
We report the discovery of a bow-shock pulsar wind nebula (PWN), named Potoroo, and the detection of a young pulsar J1638$-$4713 that powers the nebula. We present a radio continuum study of the PWN based on 20-cm observations obtained from the Australian Square Kilometre Array Pathfinder (ASKAP) and MeerKAT. PSR J1638$-$4713 was identified using Parkes radio telescope observations at frequencies above 3 GHz. The pulsar has the second-highest dispersion measure of all known radio pulsars (1 553 pc cm$^{-3}$), a spin period of 65.74 ms and a spin-down luminosity of $\dot{E}=6.1\times10^{36}$ erg s$^{-1}$. The PWN has a cometary morphology and one of the greatest projected lengths among all the observed pulsar radio tails, measuring over 21 pc for an assumed distance of 10 kpc. The remarkably long tail and atypically steep radio spectral index are attributed to the interplay of a supernova reverse shock and the PWN. The originating supernova remnant is not known so far. We estimated the pulsar kick velocity to be in the range of 1 000–2 000 km s$^{-1}$ for ages between 23 and 10 kyr. The X-ray counterpart found in Chandra data, CXOU J163802.6$-$471358, shows the same tail morphology as the radio source but is shorter by a factor of 10. The peak of the X-ray emission is offset from the peak of the radio total intensity (Stokes $\rm I$) emission by approximately 4.7$^{\prime\prime}$, but coincides well with circularly polarised (Stokes $\rm V$) emission. No infrared counterpart was found.
Double hydroxide solids precipitated homogeneously from three laboratory-synthesized aqueous solutions that simulated mildly contaminated surface or groundwater. Over a limited pH range, precipitates formed rapidly from dissolved ions, and more slowly by incorporating ions dissolving from other solids, including highly soluble aluminous solids. The precipitates were characterized by size and shape via transmission electron microscopy (TEM), by composition via inductively coupled plasma-mass spectrometry (ICP-MS) of mother solutions and analytical electron microscopy (AEM) of precipitates, and by structure via powder X-ray diffraction (XRD), TEM, and extended X-ray absorption fine structure (EXAFS) spectroscopy. They were identified as nanocrystalline cobalt hydrotalcite (CoHT) of the form [Co(II)1-xAl(III)x(OH)2]x+(An−x/n)·mH2O, with x = 0.17–0.25, A = CO32−, NO3−, or H3SiO4−n = anion charge and m undetermined. Complete solid solution may exist at the macroscopic level for the range of stoichiometrics reported, but clustering of Co atoms within hydroxide layers indicates a degree of immiscibility at the molecular scale. Composition evolved toward the Co-rich endmember with time for at least one precipitate. The small layer charge in the x = 0.17 precipitate caused anionic interlayers to be incomplete, producing interstratification of hydrotalcite and brucite-like layers. Solubility products estimated from solution measurements for the observed final CoHT stoichiometries suggest that CoHT is less soluble than the inactive forms of Co(OH)2 and CoCO3 near neutral pH. Low solubility and rapid formation suggest that CoHT solids may be important sinks for Co in contact with near neutral pH waters. Because hydrotalcite can incorporate a range of transition metals, precipitation of hydrotalcite may be similarly effective for removing other trace metals from natural waters.
X-ray absorption spectroscopy (XAS) was used to determine the local molecular environment of Co(II) surface complexes sorbed on three different kaolinites at ambient temperature and pressure in contact with an aqueous solution. Interatomic distances and types and numbers of backscattering atoms have been derived from analysis of the extended X-ray absorption fine structure (EXAFS). These data show that, at the lowest amounts of Co uptake on kaolinite (0.20–0.32 µmol m−2), Co is surrounded by ≈6 O atoms at 2.04–2.08 Å and a small number or Al or Si atoms (N = 0.6–1.5) at two distinct distances, 2.67–2.72 Å and 3.38–3.43 Å. These results indicate that Co bonds to the kaolinite surface as octahedrally coordinated, bidentate inner-sphere mononuclear complexes at low surface coverages, confirming indirect evidence from solution studies that a fraction of sorbed Co forms strongly bound complexes on kaolinite. In addition to inner-sphere complexes identified by EXAFS spectroscopy, solution studies provide evidence for the presence of weakly bound, outer-sphere Co complexes that cannot be detected directly by EXAFS. One orientation for inner-sphere complexes indicated by XAS is bidentate bonding of Co to oxygen atoms at two Al-O-Si edge sites or an Al-O-Si and Al-OH (inner hydroxyl) edge site, i.e., corner-sharing between Co octahedra and Al and Si polyhedra. At slightly higher surface sorption densities (0.51–0.57/ µmol m−2), the presence of a small number of second-neighbor Co atoms (average NCo < 1) at 3.10–3.13 Å indicates the formation of oxy- or hydroxy-bridged, multinuclear surface complexes in addition to mononuclear complexes. At these surface coverages, Co-Co and Co-Al/Si distances derived from EXAFS are consistent with edge-sharing between Co and Al octahedra on either edges or (001) faces of the aluminol sheet in kaolinite. Multinuclear complexes form on kaolinite at low surface sorption densities equivalent to <5% coverage by a monolayer of oxygen-ligated Co octahedra over the N2-BET surface area. These spectroscopic results have several implications for macroscopic modeling of metal ion uptake on kaolinite: 1) Primary binding sites on the kaolinite surface at low uptake are edge, non-bridging Al-OH inner hydroxyl sites and edge Al-O-Si bridging oxygen sites, not Si-OH sites typically assumed in sorption models; 2) specific adsorption of Co is via bidentate, inner-sphere complexation; and 3) at slightly higher uptake but still a small fraction of monolayer coverage, formation of Co multinuclear complexes, primarily edge-sharing with Al-OH octahedra, begins to dominate sorption.
Maintaining attention underlies many aspects of cognition and becomes compromised early in neurodegenerative diseases like Alzheimer’s disease (AD). The consistency of maintaining attention can be measured with reaction time (RT) variability. Previous work has focused on measuring such fluctuations during in-clinic testing, but recent developments in remote, smartphone-based cognitive assessments can allow one to test if these fluctuations in attention are evident in naturalistic settings and if they are sensitive to traditional clinical and cognitive markers of AD.
Method:
Three hundred and seventy older adults (aged 75.8 +/− 5.8 years) completed a week of remote daily testing on the Ambulatory Research in Cognition (ARC) smartphone platform and also completed clinical, genetic, and conventional in-clinic cognitive assessments. RT variability was assessed in a brief (20-40 seconds) processing speed task using two different measures of variability, the Coefficient of Variation (CoV) and the Root Mean Squared Successive Difference (RMSSD) of RTs on correct trials.
Results:
Symptomatic participants showed greater variability compared to cognitively normal participants. When restricted to cognitively normal participants, APOE ε4 carriers exhibited greater variability than noncarriers. Both CoV and RMSSD showed significant, and similar, correlations with several in-clinic cognitive composites. Finally, both RT variability measures significantly mediated the relationship between APOE ε4 status and several in-clinic cognition composites.
Conclusions:
Attentional fluctuations over 20–40 seconds assessed in daily life, are sensitive to clinical status and genetic risk for AD. RT variability appears to be an important predictor of cognitive deficits during the preclinical disease stage.
We demonstrate the importance of radio selection in probing heavily obscured galaxy populations. We combine Evolutionary Map of the Universe (EMU) Early Science data in the Galaxy and Mass Assembly (GAMA) G23 field with the GAMA data, providing optical photometry and spectral line measurements, together with Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry, providing IR luminosities and colours. We investigate the degree of obscuration in star-forming galaxies, based on the Balmer decrement (BD), and explore how this trend varies, over a redshift range of $0<z<0.345$. We demonstrate that the radio-detected population has on average higher levels of obscuration than the parent optical sample, arising through missing the lowest BD and lowest mass galaxies, which are also the lower star formation rate (SFR) and metallicity systems. We discuss possible explanations for this result, including speculation around whether it might arise from steeper stellar initial mass functions in low mass, low SFR galaxies.
Female fertility is a complex trait with age-specific changes in spontaneous dizygotic (DZ) twinning and fertility. To elucidate factors regulating female fertility and infertility, we conducted a genome-wide association study (GWAS) on mothers of spontaneous DZ twins (MoDZT) versus controls (3273 cases, 24,009 controls). This is a follow-up study to the Australia/New Zealand (ANZ) component of that previously reported (Mbarek et al., 2016), with a sample size almost twice that of the entire discovery sample meta-analysed in the previous article (and five times the ANZ contribution to that), resulting from newly available additional genotyping and representing a significant increase in power. We compare analyses with and without male controls and show unequivocally that it is better to include male controls who have been screened for recent family history, than to use only female controls. Results from the SNP based GWAS identified four genomewide significant signals, including one novel region, ZFPM1 (Zinc Finger Protein, FOG Family Member 1), on chromosome 16. Previous signals near FSHB (Follicle Stimulating Hormone beta subunit) and SMAD3 (SMAD Family Member 3) were also replicated (Mbarek et al., 2016). We also ran the GWAS with a dominance model that identified a further locus ADRB2 on chr 5. These results have been contributed to the International Twinning Genetics Consortium for inclusion in the next GWAS meta-analysis (Mbarek et al., in press).
This project surveyed Veterans’ COVID-19 vaccination beliefs and status. 1,080 (30.8%) Veterans responded. Factors associated with being unvaccinated, identified using binomial logistic regression, included negative feelings about vaccines (OR = 3.88, 95%CI = 1.52, 9.90) and logistical difficulties such as finding transportation (OR = 1.95, 95%CI = 1.01, 3.45). This highlights the need for education about and access to vaccination.
Improving the quality and conduct of multi-center clinical trials is essential to the generation of generalizable knowledge about the safety and efficacy of healthcare treatments. Despite significant effort and expense, many clinical trials are unsuccessful. The National Center for Advancing Translational Science launched the Trial Innovation Network to address critical roadblocks in multi-center trials by leveraging existing infrastructure and developing operational innovations. We provide an overview of the roadblocks that led to opportunities for operational innovation, our work to develop, define, and map innovations across the network, and how we implemented and disseminated mature innovations.
Contracting delays remain a challenge to the successful initiation of multisite clinical research in the US. The Clinical and Translational Science Awards (CTSA) Contracts Processing Study showed average contract negotiation duration of > 100 days for industry-sponsored or investigator-initiated contracts. Such delays create enormous costs to sponsors and to patients waiting to use new evidence-based treatments. With support from the National Institutes of Health’s National Center for Advancing Translational Sciences, the Accelerated Clinical Trial Agreement (ACTA) was developed by 25 major academic institutions and medical centers engaged in clinical research in collaboration with the University-Industry Demonstration Partnership and with input from pharmaceutical companies. The ACTA also informed the development of subsequent agreements, including the Federal Demonstration Partnership Clinical Trial Subaward Agreement (FDP-CTSA); both ACTA and the FDP-CTSA are largely non-negotiable agreements that represent pre-negotiated compromises in contract terms agreed upon by industry and/or medical center stakeholders. When the involved parties agree to use the CTSA-developed and supported standard agreement templates as a starting point for negotiations, there can be significant time savings for trials. Use of the ACTA resulted in an average savings of 48 days and use of the FDP-CTSA saved an average of 57 days of negotiation duration.
Uniquely comprehensive and precise, this thoroughly updated sixth edition of the well-established and respected textbook is ideal for the complete study of the kinematics and dynamics of machines. With a strong emphasis on intuitive graphical methods, and accessible approaches to vector analysis, students are given all the essential background, notation, and nomenclature needed to understand the various independent technical approaches that exist in the field of mechanisms, kinematics, and dynamics, which are presented with clarity and coherence. This revised edition features updated coverage, and new worked examples alongside over 840 figures, over 620 end-of-chapter problems, and a solutions manual for instructors.
In Chapter 11, we studied the forces in machine systems in which all forces on the bodies were in balance, and therefore the systems were in either static or dynamic equilibrium. However, in real machines this is seldom, if ever, the case except when the machine is stopped. We learned in Chapter 4 that although the input crank of a machine may be driven at constant speed, this does not mean that all points of the input crank have constant velocity vectors or that other links of the machine operate at constant speeds. In general, there will be accelerations, and therefore machines with moving parts having mass are not balanced.