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The physiology of mesophotic Scleractinia varies with depth in response to environmental change. Previous research has documented trends in heterotrophy and photosynthesis with depth, but has not addressed between-site variation for a single species. Environmental differences between sites at a local scale and heterogeneous microhabitats, because of irradiance and food availability, are likely important factors when explaining the occurrence and physiology of Scleractinia. Here, 108 colonies of Agaricia lamarcki were sampled from two locations off the coast of Utila, Honduras, distributed evenly down the observed 50 m depth range of the species. We found that depth alone was not sufficient to fully explain physiological variation. Pulse Amplitude-Modulation fluorometry and stable isotope analyses revealed that trends in photochemical and heterotrophic activity with depth varied markedly between sites. Our isotope analyses do not support an obligate link between photosynthetic activity and heterotrophic subsidy with increasing depth. We found that A. lamarcki colonies at the bottom of the species depth range can be physiologically similar to those nearer the surface. As a potential explanation, we hypothesize sites with high topographical complexity, and therefore varied microhabitats, may provide more physiological niches distributed across a larger depth range. Varied microhabitats with depth may reduce the dominance of depth as a physiological determinant. Thus, A. lamarcki may ‘avoid’ changes in environment with depth, by instead existing in a subset of favourable niches. Our observations correlate with site-specific depth ranges, advocating for linking physiology and abiotic profiles when defining the distribution of mesophotic taxa.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative–control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands’ scores.
Multivariate analysis of variance was used to analyze group differences in adjusted MCCB scores. Weighted least-squares analysis was used to investigate whether probands’ MCCB scores predicted REL neurocognitive performance.
SCZ were significantly impaired on all MCCB domains. REL had intermediate scores between SCZ and HCS, showing a similar pattern of impairment, except for social cognition. Proband's scores significantly predicted REL MCCB scores on all domains except for visual learning.
In a large sample of stable patients with schizophrenia, living in the community, and in their unaffected relatives, MCCB demonstrated sensitivity to cognitive deficits in both groups. Our findings of significant within-family prediction of MCCB scores might reflect disease-related genetic or environmental factors.
Six radio telescopes were operated as the first southern hemisphere VLBI array in April and May 1982. Observations were made at 2.3 and 8.4 Ghz. This array produced VLBI images of 28 southern hemisphere radio sources, high accuracy VLBI geodesy between southern hemisphere sites, and subarcsecond radio astrometry of celestial sources south of declination −45 degrees. This paper discusses only the astrophysical aspects of the experiment.
Mycobacterium marinum, a bacterium found in freshwater and saltwater, can infect persons with direct exposure to fish or aquariums. During December 2013, the New York City Department of Health and Mental Hygiene learned of four suspected or confirmed M. marinum skin or soft tissue infections (SSTIs) among persons who purchased whole fish from Chinese markets. Ninety-eight case-patients with non-tuberculous mycobacteria (NTM) SSTIs were identified with onset June 2013–March 2014. Of these, 77 (79%) were female. The median age was 62 years (range 30–91). Whole genome sequencing of clinical isolates revealed two main clusters and marked genetic diversity. Environmental samples from distributors yielded NTM though not M. marinum. We compared 56 case-patients with 185 control subjects who shopped in Chinese markets, frequency-matched by age group and sex. Risk factors for infection included skin injury to the finger or hand (odds ratio [OR]: 15·5; 95% confidence interval [CI]: 6·9–37·3), hand injury while preparing fish or seafood (OR 8·3; 95% CI 3·8–19·1), and purchasing tilapia (OR 3·6; 95% CI 1·1–13·9) or whiting (OR 2·7; 95% CI 1·1–6·6). A definitive environmental outbreak source was not identified.
Placental transport of vitamin D and other nutrients (e.g. amino acids, fats and glucose) to the fetus is sensitive to maternal and fetal nutritional cues. We studied the effect of maternal calorific restriction on fetal vitamin D status and the placental expression of genes for nutrient transport [aromatic T-type amino acid transporter-1 (TAT-1); triglyceride hydrolase/lipoprotein uptake facilitator lipoprotein lipase (LPL)] and vitamin D homeostasis [CYP27B1; vitamin D receptor (VDR)], and their association with markers of fetal cardiovascular function and skeletal muscle growth. Pregnant sheep received 100% total metabolizable energy (ME) requirements (control), 40% total ME requirements peri-implantation [PI40, 1–31 days of gestation (dGA)] or 50% total ME requirements in late gestation (L, 104–127 dGA). Fetal, but not maternal, plasma 25-hydroxy-vitamin D (25OHD) concentration was lower in PI40 and L maternal undernutrition groups (P<0.01) compared with the control group at 0.86 gestation. PI40 group placental CYP27B1 messenger RNA (mRNA) levels were increased (P<0.05) compared with the control group. Across all groups, higher fetal plasma 25OHD concentration was associated with higher skeletal muscle myofibre and capillary density (P<0.05). In the placenta, higher VDR mRNA levels were associated with higher TAT-1 (P<0.05) and LPL (P<0.01) mRNA levels. In the PI40 maternal undernutrition group only, reduced fetal plasma 25OHD concentration may be mediated in part by altered placental CYP27B1. The association between placental mRNA levels of VDR and nutrient transport genes suggests a way in which the placenta may integrate nutritional cues in the face of maternal dietary challenges and alter fetal physiology.
Although mental disorders are significant predictors of educational attainment throughout the entire educational career, most research on mental disorders among students has focused on the primary and secondary school years.
The World Health Organization World Mental Health Surveys were used to examine the associations of mental disorders with college entry and attrition by comparing college students (n = 1572) and non-students in the same age range (18–22 years; n = 4178), including non-students who recently left college without graduating (n = 702) based on surveys in 21 countries (four low/lower-middle income, five upper-middle-income, one lower-middle or upper-middle at the times of two different surveys, and 11 high income). Lifetime and 12-month prevalence and age-of-onset of DSM-IV anxiety, mood, behavioral and substance disorders were assessed with the Composite International Diagnostic Interview (CIDI).
One-fifth (20.3%) of college students had 12-month DSM-IV/CIDI disorders; 83.1% of these cases had pre-matriculation onsets. Disorders with pre-matriculation onsets were more important than those with post-matriculation onsets in predicting subsequent college attrition, with substance disorders and, among women, major depression the most important such disorders. Only 16.4% of students with 12-month disorders received any 12-month healthcare treatment for their mental disorders.
Mental disorders are common among college students, have onsets that mostly occur prior to college entry, in the case of pre-matriculation disorders are associated with college attrition, and are typically untreated. Detection and effective treatment of these disorders early in the college career might reduce attrition and improve educational and psychosocial functioning.
We summarise the first year of operation of the Medium Deep Survey - a key project of the HST. Two fields in the LMC are discussed and some preliminary scientific results presented. We also comment on image deconvolution for the extragalactic fields observed as part of the Medium Deep Survey.
Shortly after their discovery, it was realized that most quasars are not found in radio source catalogues, and a number of searches were initiated to try to detect weak radio emission from “optically selected quasars.”
The dates listed were obtained using a stainless steel counter with an active volume of 1.3 L and a background of 16.3 cpm at an absolute filling pressure of 152 cm Hg. The present proportional counter in use is made of O.F.H.C. copper, and has an active volume of 1.25 L and a background of 5.2 cpm, at an absolute counter filling pressure of 152 cm Hg. CO2 is used as the counting gas and the counter is filled to a pressure of between 76 cm and 228 cm of Hg (depending on the sample size) at a temperature of 23 ± 0.3°C. The counter is shielded, starting from the top, by 5 cm of lead and 26 cm of iron, and is surrounded by an array of 22 Geiger tubes, and then finally by 2.5 cm of mercury. The thickness of the sides and base is greater than 10 cm of iron. As yet no neutron shielding is used and this probably accounts for the large fluctuations of background with barometric pressure (0.32 cpm per 1 cm Hg change in the pressure).
With HST and WFPC2, galaxies in the Medium Deep Survey can be reliably classified to magnitudes I814 ≲ 22.0 in the F814W band, at a mean redshift . The main result is the relatively high proportion (~40%) of objects which are in some way irregular or anomalous, and which are of relevance in understanding the origin of the familiar excess population of faint galaxies. These diverse objects include compact galaxies, apparently interacting pairs, galaxies with superluminous starforming regions and diffuse low surface brightness galaxies of various forms. The ‘irregulars’ and ‘peculiar’ galaxies contribute most of the excess counts in the I-band at our limiting magnitude, and may explain the ‘faint blue galaxy’ problem.
Throughout the triennium, Commission 6 has interacted with the Central Bureau for Astronomical Telegrams (CBAT), most ably headed by Brian Marsden. As will be seen from his report below, the use by scientists of the Circulars for rapid dissemination of astronomical and related news continues unabated.
Post-traumatic stress disorder (PTSD) is associated with elevated risk for metabolic syndrome (MetS). However, the direction of this association is not yet established, as most prior studies employed cross-sectional designs. The primary goal of this study was to evaluate bidirectional associations between PTSD and MetS using a longitudinal design.
A total of 1355 male and female veterans of the conflicts in Iraq and Afghanistan underwent PTSD diagnostic assessments and their biometric profiles pertaining to MetS were extracted from the electronic medical record at two time points (spanning ~2.5 years, n = 971 at time 2).
The prevalence of MetS among veterans with PTSD was just under 40% at both time points and was significantly greater than that for veterans without PTSD; the prevalence of MetS among those with PTSD was also elevated relative to age-matched population estimates. Cross-lagged panel models revealed that PTSD severity predicted subsequent increases in MetS severity (β = 0.08, p = 0.002), after controlling for initial MetS severity, but MetS did not predict later PTSD symptoms. Logistic regression results suggested that for every 10 PTSD symptoms endorsed at time 1, the odds of a subsequent MetS diagnosis increased by 56%.
Results highlight the substantial cardiometabolic concerns of young veterans with PTSD and raise the possibility that PTSD may predispose individuals to accelerated aging, in part, manifested clinically as MetS. This demonstrates the need to identify those with PTSD at greatest risk for MetS and to develop interventions that improve both conditions.
Impairments in key neuropsychological domains (e.g. working memory, attention) and social cognitive deficits have been implicated as intermediate (endo) phenotypes for bipolar disorder (BD), and should therefore be evident in unaffected relatives.
Neurocognitive and social cognitive ability was examined in 99 young people (age range 16–30 years) with a biological parent or sibling diagnosed with the disorder [thus deemed to be at risk (AR) of developing BD], compared with 78 healthy control (HC) subjects, and 52 people with a confirmed diagnosis of BD.
Only verbal intelligence and affective response inhibition were significantly impaired in AR relative to HC participants; the BD participants showed significant deficits in attention tasks compared with HCs. Neither AR nor BD patients showed impairments in general intellectual ability, working memory, visuospatial or language ability, relative to HC participants. Analysis of BD-I and BD-II cases separately revealed deficits in attention and immediate memory in BD-I patients (only), relative to HCs. Only the BD (but not AR) participants showed impaired emotion recognition, relative to HCs.
Selective cognitive deficits in the capacity to inhibit negative affective information, and general verbal ability may be intermediate markers of risk for BD; however, the extent and severity of impairment in this sample was less pronounced than has been reported in previous studies of older family members and BD cases. These findings highlight distinctions in the cognitive profiles of AR and BD participants, and provide limited support for progressive cognitive decline in association with illness development in BD.
IAU Commission 6 “Astronomical Telegrams” had a single business meeting during Honolulu General Assembly of the IAU. It took place on Tuesday, 11 August 2015. The meeting was attended by Hitoshi Yamaoka (President), Daniel Green (Director of the Central Bureau for Astronomical Telegrams, CBAT, via Skype), Steven Chesley (JPL), Paul Chodas (JPL), Alan Gilmore (Canterbury University), Shinjiro Kouzuma (Chukyo University), Paolo Mazzali (Co-Chair of the Supernova Working Group), Elena Pian (Scuola Normale Superiore di Pisa), Marion Schmitz (chair IAU Working Group Designations + NED), David Tholen (University of Hawaii), Jana Ticha (Klet Observatory), Milos Tichy (Klet Observatory), Giovanni Valsecchi (INAF\slash Italy), Gareth Williams (Minor Planet Center). Apologies: Nikolai Samus (General Catalogue of Variable Stars, GCVS).
This study aimed to report the bone-anchored hearing aid uptake and the reasons for their rejection by unilateral sensorineural deafness patients.
A retrospective review of 90 consecutive unilateral sensorineural deafness patients referred to the Greater Manchester Bone-Anchored Hearing Aid Programme between September 2008 and August 2011 was performed.
In all, 79 (87.8 per cent) were deemed audiologically suitable: 24 (30.3 per cent) eventually had a bone-anchored hearing aid implanted and 55 (69.6 per cent) patients declined. Of those who declined, 26 (47.3 per cent) cited perceived limited benefits, 18 (32.7 per cent) cited reservations regarding surgery, 13 (23.6 per cent) preferred a wireless contralateral routing of sound device and 12 (21.8 per cent) cited cosmetic reasons. In all, 32 (40.5 per cent) suitable patients eventually chose the wireless contralateral routing of sound device.
The uptake rate was 30 per cent for audiologically suitable patients. Almost half of suitable patients did not perceive a sufficient benefit to proceed to device implantation and a significant proportion rejected it. It is therefore important that clinicians do not to rush to implant all unilateral sensorineural hearing loss patients with a bone-anchored hearing aid.