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During the summer of 2016, the Hawaii Department of Health responded to the second-largest domestic foodborne hepatitis A virus (HAV) outbreak in the post-vaccine era. The epidemiological investigation included case finding and investigation, sequencing of RNA positive clinical specimens, product trace-back and virologic testing and sequencing of HAV RNA from the product. Additionally, an online survey open to all Hawaii residents was conducted to estimate baseline commercial food consumption. We identified 292 confirmed HAV cases, of whom 11 (4%) were possible secondary cases. Seventy-four (25%) were hospitalised and there were two deaths. Among all cases, 94% reported eating at Oahu or Kauai Island branches of Restaurant Chain A, with 86% of those cases reporting raw scallop consumption. In contrast, a food consumption survey conducted during the outbreak indicated 25% of Oahu residents patronised Restaurant Chain A in the 7 weeks before the survey. Product trace-back revealed a single distributor that supplied scallops imported from the Philippines to Restaurant Chain A. Recovery, amplification and sequence comparison of HAV recovered from scallops revealed viral sequences matching those from case-patients. Removal of product from implicated restaurants and vaccination of those potentially exposed led to the cessation of the outbreak. This outbreak further highlights the need for improved imported food safety.
This study compared the effect of feeding AmyPlus, a moist feed, as opposed to rolled wheat on the yield and composition of milk from dairy cows consuming grass silage based total mixed ration (TMR). Seventy-two Holstein-Friesian cows were distributed into AmyPlus (Treatment) and Wheat (Control) groups and loose housed on straw in an open shed. Each kg Wheat based concentrate contained 345g rolled wheat, 230g rapeseed meal, 115g sugarbeet pulp, 115g Molaferm 20, 115g soybean meal, 56g barley straw and 24g vitamin-minerals. In contrast, each kg AmyPlus based concentrate contained 501g AmyPlus (480g DM /kg), 105g rapeseed meal, 126g sugarbeet pulp, 126g Molaferm 20, 84g soybean meal, 41g barley straw and 17g vitamin-minerals. Here, AmyPlus was loaded directly into the mixer wagon to prepare fresh AmyPlus based TMR with a silage to concentrate ratio of 68:32. Each TMR was fed once daily to the corresponding group of cows also receiving 2kg of Distillers’ grains per cow in the parlour during milking. Daily milk yield and composition was recorded from November 1999 to February 2000. The overall daily Dry matter intake (DMI) of each TMR per cow remained uniform (20.19 vs 20.15 kg for Treatment and Control group respectively) across both groups. Daily milk yield and total cell counts per cow did not vary significantly (P>0.05) between groups during various months. While, milk fat and protein contents were greater in Treatment than Control group during each month, the differences were significant (P<0.05) only during November and December for fat and in January for protein. On average, the Treatment group tended to show a non-significant increase (P>0.05) in daily milk yield per cow by 0.144 kg than the Control group. The fat (46.2 vs 43.7) and protein (34.5 vs 33.5) contents in g /kg milk were also increased significantly (P<0.001) in Treatment compared with Control group. Total cell counts did not vary significantly (P>0.05) and remained within the acceptable limits. The cows consuming AmyPlus maintained their health as indicated by their intake, production, cell counts and general appearance. It would appear that AmyPlus can replace rolled wheat in TMR. However, it may be necessary to evaluate the storage, economic and environmental implications of using such moist co-products in silage based dairy rations.
Cognitive deficits are a core feature of schizophrenia, and impairments in most domains are thought to be stable over the course of the illness. However, cross-sectional evidence indicates that some areas of cognition, such as visuospatial associative memory, may be preserved in the early stages of psychosis, but become impaired in later established illness stages. This longitudinal study investigated change in visuospatial and verbal associative memory following psychosis onset.
In total 95 first-episode psychosis (FEP) patients and 63 healthy controls (HC) were assessed on neuropsychological tests at baseline, with 38 FEP and 22 HCs returning for follow-up assessment at 5–11 years. Visuospatial associative memory was assessed using the Cambridge Neuropsychological Test Automated Battery Visuospatial Paired-Associate Learning task, and verbal associative memory was assessed using Verbal Paired Associates subtest of the Wechsler Memory Scale - Revised.
Visuospatial and verbal associative memory at baseline did not differ significantly between FEP patients and HCs. However, over follow-up, visuospatial associative memory deteriorated significantly for the FEP group, relative to healthy individuals. Conversely, verbal associative memory improved to a similar degree observed in HCs. In the FEP cohort, visuospatial (but not verbal) associative memory ability at baseline was associated with functional outcome at follow-up.
Areas of cognition that develop prior to psychosis onset, such as visuospatial and verbal associative memory, may be preserved early in the illness. Later deterioration in visuospatial memory ability may relate to progressive structural and functional brain abnormalities that occurs following psychosis onset.
Cannabis use shows a robust dose-dependent relationship with psychosis risk among the general population. Despite this, it has been difficult to link cannabis use with risk for transitioning to a psychotic disorder among individuals at ultra-high risk (UHR) for psychosis. The present study examined UHR transition risk as a function of cannabis use characteristics which vary substantially between individuals including age of first use, cannabis abuse severity and a history of cannabis-induced attenuated psychotic symptoms (APS).
Participants were 190 UHR individuals (76 males) recruited at entry to treatment between 2000 and 2006. They completed a comprehensive baseline assessment including a survey of cannabis use characteristics during the period of heaviest use. Outcome was transition to a psychotic disorder, with mean time to follow-up of 5.0 years (range 2.4–8.7 years).
A history of cannabis abuse was reported in 58% of the sample. Of these, 26% reported a history of cannabis-induced APS. These individuals were 4.90 (95% confidence interval 1.93–12.44) times more likely to transition to a psychotic disorder (p = 0.001). Greater severity of cannabis abuse also predicted transition to psychosis (p = 0.036). However, this effect was mediated by higher abuse severity among individuals with a history of cannabis-induced APS.
Findings suggest that cannabis use poses risk in a subpopulation of UHR individuals who manifest cannabis-induced APS. Whether this reflects underlying genetic vulnerability requires further study. Nevertheless, findings reveal an important early marker of risk with potentially significant prognostic utility for UHR individuals.
While the chief function and methods of operation of the Commission have remained much the same as in the past, there has been a gradual evolution in the nature of the proposals submitted. A greater fraction now come from countries in which the study of astronomy on a professional basis is as yet very recent and more proposals are being received from relatively young astronomers, although admittedly the distinction between a “young” and an “established” astronomer is not always easy to make. The commission may wish to consider whether or not it is advisable to reconsider its guidelines. Grants awarded during the interval 30 November 1981 and 31 January 1985 were the following.
UY Pup is a little studied, frequently out bursting dwarf nova whose brightness varies from V ~ 13.5 mag in outburst to V ~ 15.8 mag in quiescence, which typically lasts ~15…25 d. We observed it spectroscopically at the INT in La Palma on 1989 Febuary 15 and 16 during outburst maximum. In this outburst, the rise lasted at least 3 d and there was a long decline of about 6…9 d. The whole outburst lasted about 18 d (Mattei, private communication).
We report the analysis of 154 hours of nearly continuous high-speed photometric data on the pulsating DB white dwarf (DBV) GD 358 obtained during the Whole Earth Telescope (WET) run of May 1990. The Fourier transform (FT) of the light curve is dominated by power in the range from 1200 – 1700μHz with more than 180 significant peaks in the total transform. We also see significant power at the sums and differences of the dominant frequencies, indicating the importance of nonlinear behavior. We can use this data to obtain an accurate total stellar mass, and surface He layer mass. The implied surface He layer mass, if correct, provides a significant and surprising challenge to stellar evolution theory, as well as the theory of chemical mixing.
We present the first results from multi-site observations of the δ Scuti star XX Pyx (CD–24°7599). The observations were carried out as the 17th run of the Delta Scuti Network. We collected 583 hr of B, V time-series photometry, resulting in a detection level (4σ) in the amplitude spectrum of 0.5 mmag. We detect 6 new pulsation frequencies, bringing the total number of frequencies known in this star up 19.
White dwarf stars provide important boundary conditions for the understanding of stellar evolution. An adequate understanding of even these simple stars is impossible without detailed knowledge of their interiors. PG1346+082, an interacting binary white dwarf system, provides a unique opportunity to view the interior of one degenerate as it is brought to light in the accretion disk of the second star as the primary strips material from its less massive companion (see Wood et at. 1987).
PG1346+082 is a photometric variable with a four magnitude variation over a four to five day quasi-period. A fast Fourier transform (FFT) of the light curve shows a complex, time-dependent structure of harmonics. PG1346+082 exhibits flickering – the signature of mass transfer. The optical spectra of the system contain weak emission features during minimum and broad absorption at all other times. This could be attributed to pressure broadening in the atmosphere of a compact object, or to a combination of pressure broadening and doppler broadening in a disk surrounding the compact accretor. No hydrogen lines are observed and the spectra are dominated by neutral helium. The spectra also display variable asymmetric line profiles.
The variability of CD-24 7599 (V=11.48 mag) was discovered by JCC during observing run XCOV7 of the Whole Earth Telescope (WET, Nather et al. 1990) network in February, 1992. The star was observed as an additional target and 117 hours of high-quality temporal spectroscopic observations were obtained.
Our analysis of these data revealed the presence of 7 independent pulsation modes between 27.0 and 38.1 cycles per day (313 – 441 μHz) with semiamplitudes of 2.1 – 10.2 milli-modulation amplitudes (mma). We showed that peaks at linear combination frequencies detected in the power spectra were not due to eigenmodes excited to visible amplitude by resonant mode coupling.
Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD.
The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them.
PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples.
CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits.
Individuals identified as at ultra-high risk (UHR) for psychosis are at risk of poor functional outcome regardless of development of psychotic disorder. Studies examining longitudinal predictors of poor functioning have tended to be small and report only medium-term follow-up data. We sought to examine clinical predictors of functional outcome in a long-term longitudinal study.
Participants were 268 (152 females, 116 males) individuals identified as UHR 2–14 years previously. A range of clinical and sociodemographic variables were assessed at baseline. Functioning at follow-up was assessed using the Social and Occupational Functioning Assessment Scale (SOFAS).
Baseline negative symptoms, impaired emotional functioning, disorders of thought content, low functioning, past substance use disorder and history of childhood maltreatment predicted poor functioning at follow-up in univariate analyses. Only childhood maltreatment remained significant in the multivariate analysis (p < 0.001). Transition to psychosis was also significantly associated with poor functioning at long-term follow-up [mean SOFAS score 59.12 (s.d. = 18.54) in the transitioned group compared to 70.89 (s.d. = 14.00) in the non-transitioned group, p < 0.001]. Childhood maltreatment was a significant predictor of poor functioning in both the transitioned and non-transitioned groups.
Childhood maltreatment and transition to psychotic disorder independently predicted poor long-term functioning. This suggests that it is important to assess history of childhood maltreatment in clinical management of UHR individuals. The finding that transition to psychosis predicts poor long-term functioning strengthens the evidence that the UHR criteria detect a subgroup at risk for schizophrenia.
Model scale tests of modern ‘open rotor’ propulsor concepts that have potential for significant fuel burn reduction for aircraft applications were completed at NASA Glenn Research Center. The recent test campaign was a collaboration between NASA, FAA, and General Electric (GE). GE was the primary industrial partner, but other organisations were involved such as Boeing and Airbus who provided additional hardware for fuselage simulations. The open rotor is a modern version of the UnDucted Fan (UDF®) that was flight tested in the late 1980s through a partnership between NASA and GE. The UDF® was memorable for its scimitar shaped propeller blades and its unique noise signature. Design methods of the time were not able to optimise for both high aerodynamic efficiency and low noise simultaneously. Contemporary CFD/CAA based design methods can produce open rotor blade designs that maintain efficiency with acceptable acoustic signatures. Tests of two generations of new open rotor designs were conducted in the 9’ × 15’ Low Speed Wind Tunnel and the 8’ × 6’ Supersonic Wind Tunnel starting in late 2009 and completed in early 2012. Aerodynamic performance and acoustic data were obtained for take-off, approach and cruise conditions in isolated and semi-installed configurations. Additional detailed flow diagnostic measurements and acoustic measurements, including canonical shielding configurations, were obtained by NASA. NASA and GE conducted joint systems analysis to evaluate the performance of the new blade designs on a Boeing 737 class aircraft. The program demonstrated a 2-3% improvement in overall net efficiency relative to the best efficiency designs of the 1980s while nominally achieving 15-17 EPNdB noise margin to Chapter 4 (at a Technology Readiness Level of 5) for a notional aircraft system defined by NASA.
Whether there are differential effects of first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs) on the brain is currently debated. Although some studies report that FGAs reduce grey matter more than SGAs, others do not, and research to date is limited by a focus on schizophrenia spectrum disorders. To address this limitation, this study investigated the effects of medication in patients being treated for first-episode schizophrenia or affective psychoses.
Cortical thickness was compared between 52 first-episode psychosis patients separated into diagnostic (i.e. schizophrenia or affective psychosis) and medication (i.e. FGA and SGA) subgroups. Patients in each group were also compared to age- and sex-matched healthy controls (n = 28). A whole-brain cortical thickness interaction analysis of medication and diagnosis was then performed. Correlations between cortical thickness with antipsychotic dose and psychotic symptoms were examined.
The effects of medication and diagnosis did not interact, suggesting independent effects. Compared with controls, diagnostic differences were found in frontal, parietal and temporal regions. Decreased thickness in FGA-treated versus SGA-treated groups was found in a large frontoparietal region (p < 0.001, corrected). Comparisons with healthy controls revealed decreased cortical thickness in the FGA group whereas the SGA group showed increases in addition to decreases. In FGA-treated patients cortical thinning was associated with higher negative symptoms whereas increased cortical thickness in the SGA-treated group was associated with lower positive symptoms.
Our results suggest that FGA and SGA treatments have divergent effects on cortical thickness during the first episode of psychosis that are independent from changes due to illness.
Two new integral field units (IFUs) were installed recently on the WIYN Observatory's 3.5-meter telescope at Kitt Peak. These unique IFUs contain fibers of different sizes in the same head. This design allows smaller fibers to sample regions of higher surface brightness, providing higher spatial resolution while maintaining adequate signal-to-noise (S/N). Conversely, larger fibers maintain S/N at the expense of spatial resolution in the lower surface brightness regions of galaxies. The new IFUs were built with funds from NSF award ATI-0804576.
An actual trend to enhance solar cells efficiency is to build multijunction cells, creating a bandshape wavelength collection. However, the best multijuction cells are actually made of III-V compounds when silicon and its alloys don’t lead to high efficiency devices. In this article, we study a 3C-SiC/Si heterojunction as a first step for 3C-SiC/Si tandem cells. Four samples were fabricated by depositing 3C-SiC on Si wafers with different SiC doping levels. Simulations of the structures are performed, as well as optical and electrical characterizations of the heterojunction cells.