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Telepsychiatry (TP) can provide an alternative to traditional face-to-face (FTF) assessments. However, TP in the emergency room setting is much less prevalent, probably due to lack of solid evidence about its effectiveness and acceptability.
To directly compare traditional FTF and TP modalities in the emergency room setting.
Psychiatric patients (n=38) presented to the emergency room went through traditional in-person and videoconference TP interviews in varying order. Both FTF and TP interviewers that examined the patients as well as a third psychiatrist, acting as an observer for both modalities, determined the diagnosis, disposition recommendation and indication for involuntary admission.
Rater decisions had a high matching on disposition and indication for involuntary admission (Cohen’s Kappa (CK) of 0.84/0.81, 0.95/0.87 and 0.89/0.94 for FTF-TP, Observer-FTF and Observer-TP, respectively). Although identical diagnosis matching between the raters was relatively low, the partial diagnosis matching was high (CK of 0.52/0.81, 0.52/0.85 and 0.56/0.85 for FTF-TP, Observer-FTF and Observer-TP, respectively). Telepsychiatry assessments had comparable acceptability in items such as psychiatrists’ certainty and interviewers’ and patients’ satisfaction.
TP and FTF psychiatric assessments in the emergency room settings have similar validity and acceptability. Implementation of TP in emergency room settings might improve the mental health services’ quality and access especially for remote populations. TP is especially important during the COVID-19 pandemic to enable treatment for epidemiologically isolated patients and to protect the medical personnel.
Post-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations.
Data were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11.
CFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time.
Results of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.
Longitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders.
A total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks.
Among police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories.
Trajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.
To examine the prevalence of the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and the A2756G polymorphism of methionine synthase (MS), and their impact on antidepressant response.
We screened 224 subjects (52% female, mean age 39 ± 11 years) with SCID-diagnosed major depressive disorder (MDD), and obtained 194 genetic samples. 49 subjects (49% female, mean age 36 ± 11 years) participated in a 12-week open clinical trial of fluoxetine 20–60 mg/day. Association between clinical response and C677T and A2756G polymorphisms, folate, B12, and homocysteine was examined.
Prevalence of the C677T and A2756G polymorphisms was consistent with previous reports (C/C = 41%, C/T = 47%, T/T = 11%, A/A = 66%, A/G = 29%, G/G = 4%). In the fluoxetine-treated subsample (n = 49), intent-to-treat (ITT) response rates were 47% for C/C subjects and 46% for pooled C/T and T/T subjects (nonsignificant). ITT response rates were 38% for A/A subjects and 60% for A/G subjects (nonsignificant), with no subjects exhibiting the G/G homozygote. Mean baseline plasma B12 was significantly lower in A/G subjects compared to A/A, but folate and homocysteine levels were not affected by genetic status. Plasma folate was negatively associated with treatment response.
The C677T and A2756G polymorphisms did not significantly affect antidepressant response. These preliminary findings require replication in larger samples.
A 60-year-old patient with a clinical diagnosis of schizophrenia underwent a magnetic resonance imaging (MRI) scan related to the evaluation of isolated seizures that emerged while medicated with clozapine. Unexpectedly, the MRI scan revealed evidence of asymmetric and enlarged cerebral ventricles that were interpreted as congenital in origin. The presence of both congenital lateral ventricular asymmetry and ventriculomegaly may interact to increase risk of schizophrenia. The history and clinical features, including cognitive testing, of the illustrative patient are presented.
We have chosen the name of GYES, one of the mythological giants with one hundred arms,
offspring of Gaia and Uranus, for our instrument study of a multifibre spectrograph for
the prime focus of the Canada-France-Hawaii Telescope. Such an instrument could provide an
excellent ground-based complement for the Gaia mission and a northern complement to the
HERMES project on the AAT. The CFHT is well known for providing a stable prime focus
environment, with a large field of view, which has hosted several imaging instruments, but
has never hosted a multifibre spectrograph. Building upon the experience gained at GÉPI
with FLAMES-Giraffe and X-Shooter, we are investigating the feasibility of a high
multiplex spectrograph (about 500 fibres) over a field of view one degree in diameter. We
are investigating an instrument with resolution in the range 15 000 to 30 000, which
should provide accurate chemical abundances for stars down to 16th magnitude and radial
velocities, accurate to 1 km s-1 for fainter stars. The study is led by
GÉPI-Observatoire de Paris with a contribution from Oxford for the study of the
positioner. The financing for the study comes from INSU CSAA and Observatoire de Paris.
The conceptual study will be delivered to CFHT for review by October 1st 2010.
Recent laboratory measurements of plasma expansion in a plasma wake experiment are compared with analytical expressions which approximate the plasma expansion model of Crow, Auer & Allen. Good quantitative agreement was found between the data and theory for the velocity and position of the ion expansion front. These results provide an important insight into the behaviour of the expansion early in its development.
Carbon nanocapsules with a ferromagnetic core of single-crystalline Fe3O4 are demonstrated to be effectively synthesized and collected separately from the other nano-carbon products of the low-temperature reaction of catalytic disproportionation of carbon monoxide. HRTEM demonstrated a defect-free crystalline structure of the Fe3O4 nanoparticles. The encapsulating carbon shells of the Fe3O4 nanoparticles are stable in air at room temperature, but do not prevent them at high temperatures. Accordingly, these nanoparticles may also act as catalysts for the corresponding production of carbon nanomaterials via carbon monoxide disproportionation. In particular, we demonstrate the corresponding transformation of a Fe3O4 core to an iron carbide nanoparticle with simultaneous formation of additional encapsulating carbon layers. Characterization of the synthesized materials by DC magnetization represents clearly resolved hysteresis loops. However characteristic S-shape of the loops (magnetization is still not saturated at 16 kOe) points out some superparamagnetic effects driven by the nano-size origin of the samples. Analysis of the sample's EPR spectra provides an additional insight to the coexistence of several magnetic phases in the synthesized nanomaterials.
Photospheric parameters and abundances of 13 chemical species are presented for a sample of single-lined chromospherically active binaries from a differential LTE analysis of high-resolution spectra. Our results indicate that the X-ray active binaries studied are not as metal poor as previously claimed, but are at most mildly iron-depleted relative to the Sun (—0.41 ≲ [Fe/H] ≲ +0.11). A significant overabundance of several elements (e.g., Na, Mg, Al, Ca) is observed. The temperatures derived from the (V — R) and (V — I) colours are found to be significantly affected by activity processes.
Phylogenetic analyses of chloroplast gene (rbcL, matK), intron (rpl16, rps16, rpoC1) and nuclear ribosomal DNA internal transcribed spacer (ITS) sequences and chloroplast DNA restriction sites, with supplementary data from variation in size of the chloroplast genome inverted repeat, have been used to elucidate major clades within Apiaceae (Umbelliferae) subfamily Apioideae Drude. This paper summarizes the results of previously published molecular cladistic analyses and presents a provisional classification of the subfamily based on taxonomic congruence among the data sets. Ten tribes (Aciphylleae M. F. Watson & S. R. Downie, Bupleureae Spreng., Careae Baill., Echinophoreae Benth., Heteromorpheae M. F. Watson & S. R. Downie, Oenantheae Dumort., Pleurospermeae M. F. Watson & S. R. Downie, Pyramidoptereae Boiss., Scandiceae Spreng. and Smyrnieae Spreng.) are erected or confirmed as monophyletic, with Scandiceae comprising subtribes Daucinae Dumort., Scandicinae Tausch and Torilidinae Dumort. Seven additional clades are also recognized but have yet to be treated formally, and at least 23 genera examined to date are of dubious tribal or clade placement. The utility of these different molecular markers for phylogenetic inference in Apioideae is compared based on maximum parsimony analyses of subsets of previously published molecular data sets. Of the six loci sequenced, the ITS region is seen to be evolving most rapidly and rbcL is the most conservative. Intermediate in rate of evolution are matK and the three chloroplast introns; with rpl16 and rps16 evolving slightly faster than matK or rpoC1. The analysis of restriction sites, however, provided 2–4 times more parsimony informative characters than any single DNA locus sequenced, with estimates of divergence just slightly lower than that of the ITS region. The trees obtained from separate analyses of these reduced data sets are consistent with regard to the major clades inferred and the relationships among them. Similar phylogenies are obtained by combining data or combining trees, representing the supermatrix and supertree approaches to phylogenetic analysis, respectively. The inferred relationship among the tribes and informally recognized major clades within Apioideae is presented.
For several microelectronics applications, Cu/dielectric adhesion is a key reliability issue. Either electroplating or local galvanic coupling under moist operating conditions may result in hydrogen induced interface weakening. The present study compared hydrogen effects on Cu/SiO2 adhesion for sputter deposited f'dms with and without Ti underlayers. Thin Cu and Cu/Ti films ranging from 80–3000 nm have been evaluated. Direct observations of the surface during electrolytic charging have shown no evidence of film/substrate debonding for Cu/Ti systems. In contrast, extensive delaminations have been observed for Cu films. Indentation testing immediately after charging indicated up to 100% decrease in the practical adhesion for Ti/Cu films. The observed effect resulted from a true interfacialfracture energy reduction from 4 to 2 J/m2, Plastic energy dissipation was assumed unaffected as no yield stress changes were detected after charging. Even with the deleterious effect of hydrogen, adhesion strength of Cu/Ti films remained higher than that of non-charged Cu films.
The effects of external two-dimensional excitation on the plane turbulent wall jet were investigated experimentally and theoretically. Measurements of the streamwise component of velocity were made throughout the flow field for a variety of imposed frequencies and amplitudes. The present data were always compared to the results generated in the absence of external excitation. Two methods of forcing were used: one global, imposed on the entire jet by pressure fluctuations in the settling chamber and one local, imposed on the shear layer by a small flap attached to the outer nozzle lip. The fully developed wall jet was shown to be insensitive to the method of excitation. Furthermore, external excitation has no appreciable effect on the rate of spread of the jet nor on the decay of its maximum velocity. In fact the mean velocity distribution did not appear to be altered by the external excitation in any obvious manner. The flow near the surface, however, (i.e. for 0 < Y+ < 100) was profoundly different from the unforced flow, indicating a reduction in wall stress exceeding at times 30%. The production of turbulent energy near the surface was also reduced, lowering the intensities of the velocity fluctuations. External excitation enhanced the two-dimensionality and the periodicity of the coherent motion. Spectral analysis and flow visualization suggested that the large coherent structures in this flow might be identified with the most-amplified primary instability modes of the mean velocity profile. Detailed stability analysis confirmed this proposition though not at the same level of accuracy as it did in many free shear flows.
The spatial distribution of the mean velocity in a two-dimensional turbulent wall jet was measured for a variety of nozzle Reynolds numbers. It was determined that the bulk of the flow is self-similar and it depends on the momentum flux at the nozzle and on the viscosity and density of the fluid. The width of the nozzle which was commonly used to reduce these data has no part in the similarity considerations as has already been suggested by Narasimha et al. (1973). This type of self-similarity can be easily applied to determine the skin friction, which can otherwise only be determined with considerable difficulty. It was also shown that the ‘law of the wall’ applies only to the viscous sublayer. The Reynolds stress in the inviscid, inner portion of the flow is not constant thus the assumption of a ‘constant stress layer’ is not applicable. The applicability and universality of the ‘outer scaling law’ (i.e. Coles’ law of the wake) has been verified throughout the inviscid inner portion of the wall jet. The logarithmic velocity distribution cannot be derived by making the usual assumptions based on the constancy of the Reynolds stresses or on the thinness of the logarithmic region relative to the thickness of the inner layer.
The evolution of a turbulent spot in an accelerating laminar boundary-layer flow was investigated. The type of boundary layer chosen for this experiment resembles in every respect the flow in the vicinity of a stagnation point theoretically described by Falkner and Skan. The rate of growth of the spot was significantly inhibited by the favourable pressure gradient in all three directions. It became much shorter and narrower in comparison with a similar spot generated in a Blasius boundary layer at comparable distances from its origin and comparable Reynolds numbers. The celerities of its boundaries did not scale with the local free-stream velocity as they do in the absence of a pressure gradient. Dimensional analysis was used to identify and correlate the independent variables determining the size, the convection speed, and the relative rate of growth of this spot
The familiar arrowhead shape of the spot gave way to a rounded triangular shape with the trailing interface being straight and perpendicular to the direction of streaming. The familiar Tollmien-Schlichting wave packet was not observed in this pressure gradient because the surrounding boundary layer was very stable at the Re considered. Since the arrowhead shape of the spot is associated with the breakdown of the waves within the packet it cannot occur below the critical Re. The relative size of the ‘calmed region’ following the spot also diminished; however, one could only speculate as to the origin of this region.
We have investigated the formation of IrSi3 layers buried in <111> silicon. The layers are formed by iridium ion implantation using a metal vapor vacuum arc (MEVVA) high current metal ion source at room temperature with average beam energy = 130 keV. Doses of the Ir ions ranging from 2×1016 to 1.5×1017/cm2 were implanted into <111> Si. The formation of IrSi3 phase is realized after annealing at temperatures as low as 500°C. A continuous IrSi3 layer of =200 Å thick buried under =400 Å Si was achieved with samples implanted with doses not less than 3.5×1016/cm2. Implantated doses above 8×1016/cm2 resulted in the formation of an IrSi3 layer on the surface due to excessive sputtering of Si by the TI ions. The effects of implant dose on phase formation, interface morphology and implanted atom redistribution are discussed. Radiation damage and regrowth of Si due to the implantation process was also studied.