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During the past two decades, it has been amply documented that neuropsychiatric disorders (NPDs) disproportionately account for burden of illness attributable to chronic non-communicable medical disorders globally. It is also likely that human capital costs attributable to NPDs will disproportionately increase as a consequence of population aging and beneficial risk factor modification of other common and chronic medical disorders (e.g., cardiovascular disease). Notwithstanding the availability of multiple modalities of antidepressant treatment, relatively few studies in psychiatry have primarily sought to determine whether improving cognitive function in MDD improves patient reported outcomes (PROs) and/or is cost effective. The mediational relevance of cognition in MDD potentially extrapolates to all NPDs, indicating that screening for, measuring, preventing, and treating cognitive deficits in psychiatry is not only a primary therapeutic target, but also should be conceptualized as a transdiagnostic domain to be considered regardless of patient age and/or differential diagnosis.
Most studies underline the contribution of heritable factors for psychiatric disorders. However, heritability estimates depend on the population under study, diagnostic instruments, and study designs that each has its inherent assumptions, strengths, and biases. We aim to test the homogeneity in heritability estimates between two powerful, and state of the art study designs for eight psychiatric disorders.
We assessed heritability based on data of Swedish siblings (N = 4 408 646 full and maternal half-siblings), and based on summary data of eight samples with measured genotypes (N = 125 533 cases and 208 215 controls). All data were based on standard diagnostic criteria. Eight psychiatric disorders were studied: (1) alcohol dependence (AD), (2) anorexia nervosa, (3) attention deficit/hyperactivity disorder (ADHD), (4) autism spectrum disorder, (5) bipolar disorder, (6) major depressive disorder, (7) obsessive-compulsive disorder (OCD), and (8) schizophrenia.
Heritability estimates from sibling data varied from 0.30 for Major Depression to 0.80 for ADHD. The estimates based on the measured genotypes were lower, ranging from 0.10 for AD to 0.28 for OCD, but were significant, and correlated positively (0.19) with national sibling-based estimates. When removing OCD from the data the correlation increased to 0.50.
Given the unique character of each study design, the convergent findings for these eight psychiatric conditions suggest that heritability estimates are robust across different methods. The findings also highlight large differences in genetic and environmental influences between psychiatric disorders, providing future directions for etiological psychiatric research.
On 1982 Jan. 9 a brightening of 0.75 mag of the OIafpe star R127 (=HDE 269858) was detected. Subsequently extensive photometric (optical and infrared) and high resolution spectroscopic (ground-based and IUE) observations covering a period of more than one year have been carried out. These observations have shown R127 to be a new S Dor variable which is hotter than any previously detected and studied variable of this class. For its maximum phase we derived the following basic parameters: Mbol = −10.6, Teff = 16000 K, R* = 150 R⊙. The stellar wind is characterized by a small mean velocity (v = 110 km s−1), a high mass loss rate (M = 6 · 10−5 M⊙yr−1), and a decelerated velocity field. The optical spectra show strong Balmer lines with P Cygni profiles. The He I lines changed within the one year period from strong P Cygni type lines to complex line profiles with extremely wide (FWZI = 3000 km s−1) shallow emission line wings. The IUE spectra are dominated by crowded absorption lines of singly ionized metals. A very complex shell phenomenon is indicated by the multiple substructure of these ultraviolet lines. We suggest that R127 is a massive (M > 60 M⊙) Of star evolving via a short-lived S Doradus phase to a late WN star.
We carried out a spectroscopic and photometric study of the 8 presently known B[e] -stars of the Magellanic Clouds (MC), i. e. R4 and R50 of the SMC, R66, R82, R126, Hen S12, Hen S22 and Hen S134 of the LMC. These stars are characterized by the following typical properties: a) strong Balmer emission lines, frequently with P Cygni profiles, b) permitted and forbidden emission lines predominantly of Fe II, [Fe II], [O I] etc., c) strong IR excess due to circumstellar dust. Photospheric absorption lines are usually weak or even not detectable.
We analysed highly resolved CASPEC spectra with a high S/N-ratio of the peculiar emission-line B-star MWC 300, which is surrounded by a circumstellar dust shell. These high quality spectra enabled us to study the photospheric spectrum of MWC 300. By comparing the absorption spectrum of MWC 300 with the ones of early B supergiants we found a close resemblance with the B1 hypergiant HD 169454. We also found luminosity sensitive fluorescence lines of Fe III 115 and 117 both in MWC 300 and in the most luminous stars of our sample, confirming the hypergiant nature of MWC 300. We estimated an absolute visual magnitude Mv = −8 for MWC 300. Assuming a bolometric correction of B.C. = −1.5 mag we derive Mbol = −9.5. This shows that MWC 300 is very similar to the B e supergiants of the Magellanic Clouds. From its absolute magnitude we derive a distance of z = 560 pc from the galactic plane. It is conjectured that MWC 300 is a runaway hypergiant, released via a supernova explosion in a very massive binary star system.
Using the CASPEC echelle spectrograph of the European Southern Observatory, La Silla, Chile, we obtained new high resolution spectrograms of the LMC S Dor variable R 127 in the blue and red spectral range.
The red spectrogram, which contains the [N II] 6548 and 6533 and the [S II] 6717 and 6731 lines shows the presence of a well resolved extended gaseous nebula around R 127 (see Figures 1 and 2). The nebula (which is also detected at the Balmer lines) shows blueshifted and redshifted emission (projected) on the position of the stellar continuum, and no wavelength-shift at the maximum (East-West) distance from the star. Hence, the nebulosity appears to be an expanding shell, reminiscent of the nebula around the galactic extreme supergiant AG Car. The angular diameter (or East-West extension) of the nebula around R 127 is of the order 4“, corresponding to ≈1 pc at the distance of the LMC. The expansion velocity of the R 127 nebula is found to be 28 km s−1 from our spectrograms. Hence, assuming a constant expansion velocity we derive a kinematic age of the R 127 nebula of ≈2 · 104 years. This corresponds closely to the expected lifetime of the S Dor evolutionary phase.
A more detailed description of our results will be published in the proceedings of the Workshop on “Instabilities in Luminous Early Type Stars” (C. de Loore, H. Lamers, eds.) Lunteren 1986.
HD 37836 (= R 123; Feast et al., 1960) is one of the brightest slightly variable (V ≃ 10.5–10.7; Stahl et al., 1984) emission-line stars of the LMC. Since it is also likely to be a hot star (see below) it is also bolometrically very bright (Mbol ≤ −11).
We present an atlas of high dispersion spectra of 24 of the brightest peculiar emission-line stars of the Magellanic Clouds.
Our spectra cover the wavelength range from 3600 to 4900 Å. They have been obtained from 1970 to 1984 with the coudé spectrograph of the ESO 1.52 m telescope at La Silla, Chile. The spectral resolution is 0.4 Å for most of the spectra and 0.2 Å for the very brightest stars. Up to 11 spectra are available for one star. In addition, we have done UBVRIJHK(LM) photometry at several epochs of all stars of our sample.
We present coordinated spectroscopic and photometric observations obtained during the present bright phase of the luminous variable star S Dor in the LMC. High resolution spectrograms in the satellite UV and in the visual range were obtained with IUE and with CASPEC (attached to the ESO 3.6-m telescope), respectively. Moreover, photometric UBVRIJHKL observations were carried out.
We examined longitudinally the course and predictors of treatment resistance in a large cohort of first-episode psychosis (FEP) patients from initiation of antipsychotic treatment. We hypothesized that antipsychotic treatment resistance is: (a) present at illness onset; and (b) differentially associated with clinical and demographic factors.
The study sample comprised 323 FEP patients who were studied at first contact and at 10-year follow-up. We collated clinical information on severity of symptoms, antipsychotic medication and treatment adherence during the follow-up period to determine the presence, course and predictors of treatment resistance.
From the 23% of the patients, who were treatment resistant, 84% were treatment resistant from illness onset. Multivariable regression analysis revealed that diagnosis of schizophrenia, negative symptoms, younger age at onset, and longer duration of untreated psychosis predicted treatment resistance from illness onset.
The striking majority of treatment-resistant patients do not respond to first-line antipsychotic treatment even at time of FEP. Clinicians must be alert to this subgroup of patients and consider clozapine treatment as early as possible during the first presentation of psychosis.
At the John F. Kennedy International Airport in New York City, disaster planning has been an integral part of the airport operations for the past 28 years. Through the Medical Office, emergency medical teams have been recruited from all ranks of airport personnel and trained in rescue and resuscitation. Following the crash of a commercial B 727 aircraft in 1976 and the resulting crippling traffic jams in the vicinity of the airport, a new concept was added to the disaster plan. This concept involves bringing the hospital, its facilities and its personnel to the scene.
A new piece of equipment, known as a Mobile Emergency Hospital was designed from existing airport equipment, with the cooperation of the airlines, the operating authority of the airport, and other interested parties. Two such vehicles are now in constant readiness at the airport and together provide 12 monitored ICU beds, a 16-bed burn unit, 2 operating rooms and 72 other stretcher-beds to be used for the stabilization of critically ill patients prior to their transfer to an appropriate definitive care facility. A newer modularized version which incorporates these features, for use in any type disaster, is currently being developed. These mobile hospitals, together with two inflatable structures maintained at the airport, are supplemented by Mobile Emergency Rescue Vehicles (MERV vans) maintained at local hospitals by the Emergency Medical Service Systems (EMSS) of New York City. Together they provide the on-site Resuscitation and Stabilization Center in the event of a disaster.
The LMC star R127 was classified as O Iafpe extr. by Walborn (1977). Later, Walborn (1982) noted the spectral similarity to late WN stars and classified R127 as Ofpe/WN9 star. Stahl et al. (1983) discovered an S Dor outburst of R127. It has now been monitored photometrically almost continuously for more than four years. In addition, several high-dispersion and high signal-to-noise spectra were taken with the ESO CASPEC and CES spectrographs. In 1986 R127 became the visually brightest star of the LMC until it was surpassed by SN1987A in Feb. 1987.
The Ofpe/WN9 stars R84 and S61 of the LMC have been studied with high-dispersion spectroscopy in the optical and satellite-UV range. The high resolution and high S/N spectra in the optical range are particularly distinguished by strong emission lines of H, HeI and [NII]. The comparison of R84 with S61 shows that the peculiar emission line spectrum is not caused by the previously found late type companion of R84. We find that the UV spectra of both stars closely resemble those of late O-supergiants but all absorption lines are violet-shifted by about 250 km s−1 (R84) and about 200 km s−1 (S61). The absorption lines are stronger than in normal O-type stars. The UV-resonance lines indicate low terminal wind velocities of ≈ 900 km s−1 only. Unlike to normal O-type stars the AlIII-resonance lines also show pronounced P Cygni profiles with an even lower edge velocity (vedge ≈ 400 km s−1). Tne mass loss rates (>6.10−6 Mo yr−1) are comparable to rates found in normal luminous hot stars. However, the wind appears to be much more gradually accelerated similar to the wind of the galactic supergiant P Cygni. It is suggested that the Ofpe/WN9 transition type stars are the hotter counterparts of the early B-type P Cygni stars.
High resolution spectrograms of B stars in the blue globular cluster NGC 2004, located in the Large Magellanic Cloud (LMC), have been used to derive chemical abundances, differentially with respect to a galactic comparison star.
From the free-free excess at 10μ. Barlow and Cohen (1977) (hereafter referred to as BC) derived a mass loss rate of 6.9 10-7 M⊙ yr-1 for α Cyg. They predicted a 10 GHz radio flux of 2.2 mJy. On the other hand Praderie et al. (1980) derived a considerable lower mass loss rate of 1.1 10 -8 ≤Ṁ ≤ 7 10-8 M ⊙ yr-1 from a curve of growth analysis of the envelope ultraviolet Fell-lines of α Cyg. Radio observations are desirable to make a decision about these discrepant results. Therefore we observed α Cyg at 15 GHz with the 100 m telescope of the MPIfR at Effelsberg. The observations are discussed together with recent VLA data of Abbott et al. (1980).
Spectra of the Be star 28 CMa obtained with the HEROS echelle spectrograph in 1996 and 1997 were used to check the presence of transient periods in commonly measured scalar parameters of absorption and emission lines. Transient periods can be convincingly detected in modes of higher absorption and single peak emission lines of the Balmer series as well as in the V/R ratio of Fell lines. Consequences for the frequency analyses of datasets containing radial velocities derived from different ions are discussed. The significant differences in amplitudes of radial velocities of different ions and in individual seasons were confirmed and a mean ephemeris derived.
A multi-faceted, multi-institutional laboratory astrophysics program is carried out at the Livermore electron beam ion trap facility, which is a mature spectroscopic source with unsurpassed controls and capabilities, and an unparalleled assortment of spectroscopic equipment, including a full complement of grating and crystal spectrometers and a 6x6 micro-calorimeter array. Recent results range from the calibration of x-ray diagnostics, including the Fe XVII and Fe XXV emission lines, extensive lists of L-shell ions, the first laboratory simulation and fit of a cometary x-ray emission spectrum, and the discovery of new spectral diagnostics for measuring magnetic field strengths.