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A new optimized quasi-helically symmetric configuration is described that has the desirable properties of improved energetic particle confinement, reduced turbulent transport by three-dimensional shaping and non-resonant divertor capabilities. The configuration presented in this paper is explicitly optimized for quasi-helical symmetry, energetic particle confinement, neoclassical confinement and stability near the axis. Post optimization, the configuration was evaluated for its performance with regard to energetic particle transport, ideal magnetohydrodynamic stability at various values of plasma pressure and ion temperature gradient instability induced turbulent transport. The effects of discrete coils on various confinement figures of merit, including energetic particle confinement, are determined by generating single-filament coils for the configuration. Preliminary divertor analysis shows that coils can be created that do not interfere with expansion of the vessel volume near the regions of outgoing heat flux, thus demonstrating the possibility of operating a non-resonant divertor.
Although the Peritraumatic Distress Inventory (PDI) and Peritraumatic Dissociative Experiences Questionnaire (PDEQ) are both useful for identifying adults at risk of developing acute and chronic post-traumatic stress disorder (PTSD), they have not been validated in school-aged children. The present study aims at assessing the psychometric properties of the PDI and PDEQ in a sample of French-speaking school children.
One-hundred and thirty-three school-aged victims of road traffic accidents were consecutively enrolled into this study via the emergency room. Mean(SD) age was 11.7(2.2) and 56.4% (n=75) of them were of male gender. The 13-item self-report PDI (range 0-52) and the 10-item self report PDEQ (range 10-50) were assessed within one week of the accident. Symptoms of PTSD were assessed 1 and 6 months later using the 20-item self-report Child Post-Traumatic Stress Reaction Index (CPTS-RI) (range 0-80).
Mean(SD) PDI and PDEQ scores were 19.1(10.1) and 21.1(7.6), respectively, while mean(SD) CPTS-RI scores at 1- and 6-months were 22.6(12.4) and 20.6(13.5), respectively. Cronbach's alpha coefficients were 0.8 and 0.77 for the PDI and PDEQ, respectively. The 1-month test-retest correlation coefficient (n=33) was 0.77 for both measures. The PDI demonstrated a 2-factor structure while the PDEQ displayed a 1-factor structure. As with adults, the two measures were inter-correlated (r=0.52) and correlated with subsequent PTSD symptoms (r=0.21−0.56; p< 0.05).
The PDI and PDEQ are reliable and valid in school-aged children, and predict PTSD symptoms.
It remains unknown whether peritraumatic reactions predict PTSD symptoms in younger populations. To prospectively investigated the power of self-reported peritraumatic distress and dissociation to predict the development of PTSD symptoms at 1-month in school-aged children.
A sample of 103 school-aged children (8-15 years old) admitted to an Emergency Department after a road traffic accident were consecutively enrolled. Peritraumatic distress was assessed using the Peritraumatic Distress Inventory (range 0-52) and peritraumatic dissociation was assessed using the Peritraumatic Dissociative Experiences Questionnaire (PDEQ) (range 10-50). PTSD symptoms were measured at 1-month by both the child version of the clinician-administered PTSD Scale (CAPS-CA) (range: 0-136) and the Child Post-traumatic Stress Reaction Index (CPTS-RI) (range 0-80).
Mean(SD) participants’ age was 11.7(2.2) and 53.4% (n=55) of them were of male gender. At baseline, mean PDI and PDEQ scores were 21.4 (SD=7.8) and 19.2 (SD=10.2), respectively. At 1-month, mean self-reported (CPTS-RI) and interviewer-based (CAPS-CA) PTSD symptom scores were 23.2 (SD=12.1) and 19 (SD=16.9), respectively. According to the CAPS-CA, 5 children (4.9%) suffered from full PTSD. Bivariate analyses demonstrated a significant association between peritraumatic variables (PDI and PDEQ) and both CAPS-CA and CPTS-RI (r=0.22-0.57; all p< 0.05). However, in a multivariate analysis, PDI was the only significant predictor of acute PTSD symptoms (Beta=0.33, p< 0.05).
As has been found in adults, peritraumatic distress is a robust predictor of who will develop PTSD symptoms among school-aged children.
Violent behaviors in psychiatric emergency departments are a common problem. The aim is to study characteristics of patients who need intense preventive care measures and who act violently.
The study was conducted in a locked short term psychiatric inpatient unit and involved 172 patients admitted in a 8 months period. Sociodemographic and clinical data were obtained through a review of the medical records. Secclusion, restraint and agressive behaviors were noted on specific nurse sheets.
Aggressive behaviors or intense preventive measures concerned 34% (n=59) of the 172 patients. Among these 59 patients, 61% (n=36) are men and the mean age is 34,9 years, 28 had seclusion, 51 had restraint and 11 had physical aggression or against object aggression. The diagnosis are schizophrenic disorders for 63% (n=37), dependence or substance abuse for 11% (n=7), mania for 10% (n=6), depression for 3,5% (n=2). For 27% (n=16) of them it was first time in Emergency Department and 30,5% (n=18) were intoxicated at admission. The mean neuroleptic treatments dosis of these patients at admission were 656mg (equivalent chlorpromazine).
Patients concerned by seclusion, restraint and aggressive behavior are more frequently men with schizophrenic disorders, high neuroleptic dosis, and various past admissions in the Emergency Department.
Increasing evidence suggests that clock genes may be implicated in a spectrum of psychiatric diseases, including sleep and mood related disorders as well as schizophrenia. The bHLH transcription factors SHARP1/DEC2/BHLHE41 and SHARP2/DEC1/BHLHE40 are modulators of the circadian system and SHARP1/DEC2/BHLHE40 has been shown to regulate homeostatic sleep drive in humans.
In this study, we characterized Sharp1 and Sharp2 double mutant mice (S1/2-/-) using online EEG recordings in living animals, behavioral assays, global gene expression profiling and bioinformatic modeling. Gene expression in human brains samples was performed with qRT-PCR.
EEG recordings revealed attenuated sleep/wake amplitudes and alterations of theta oscillations. Increased sleep in the dark phase is paralleled by reduced voluntary activity and cortical gene expression signatures reveal associations with psychiatric diseases. S1/2-/- mice display alterations in novelty induced activity, anxiety and curiosity. Moreover, mutant mice exhibit impaired working memory and deficits in prepulse inhibition resembling symptoms of psychiatric diseases. Network modeling indicates a connection between neural plasticity and clock genes, particularly for SHARP1 and PER1, which are also significantly downregulated in the frontal cortex of schizophrenic patients.
Our findings support the hypothesis that abnormal sleep and certain (endo)phenotypes of psychiatric diseases may be caused by common mechanisms involving components of the molecular clock including SHARP1 and SHARP2
We have analyzed Chandra/High Energy Transmission Grating spectra of the X-ray emission line gas in the Seyfert galaxy NGC 4151. The zeroth-order spectral images show extended H- and He-like O and Ne, up to a distance r ˜ 200 pc from the nucleus. Using the 1st-order spectra, we measure an average line velocity ˜230 km s–1, suggesting significant outflow of X-ray gas. We generated Cloudy photoionization models to fit the 1st-order spectra; the fit required three distinct emission-line components. To estimate the total mass of ionized gas (M) and the mass outflow rates, we applied the model parameters to fit the zeroth-order emission-line profiles of Ne IX and Ne X. We determined an M ≍ 5.4 × 105Mʘ. Assuming the same kinematic profile as that for the [O III] gas, derived from our analysis of Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra, the peak X-ray mass outflow rate is approximately 1.8 Mʘ yr–1, at r ˜ 150 pc. The total mass and mass outflow rates are similar to those determined using [O III], implying that the X-ray gas is a major outflow component. However, unlike the optical outflows, the X-ray emitting mass outflow rate does not drop off at r > 100pc, which suggests that it may have a greater impact on the host galaxy.
Stellarator configurations with reactor relevant energetic particle losses are constructed by simultaneously optimizing for quasisymmetry and an analytically derived metric (
), which attempts to align contours of the second adiabatic invariant,
with magnetic surfaces. Results show that with this optimization scheme it is possible to generate quasihelically symmetric equilibria on the scale of ARIES-CS which completely eliminate all collisionless alpha particle losses within normalized radius
. We show that the best performance is obtained by reducing losses at the trapped–passing boundary. Energetic particle transport can be improved even when neoclassical transport, as calculated using the metric
, is degraded. Several quasihelically symmetric equilibria with different aspect ratios are presented, all with excellent energetic particle confinement.
Flaviviruses include many viruses causing encephalitis, including West Nile encephalitis, St. Louis encephalitis, tick-borne encephalitis and Japanese encephalitis. Human pegivirus genotype-1 (HPgV-1) is a lesser known member of the Flaviviridae family and has been identified in human serum, cerebrospinal fluid and brain tissue. Here, we describe two adult patients with fatal HPgV-1-associated encephalitis. Neuroimaging revealed multifocal lesions, initially present in the periventricular and brain stem white matter, then one year later throughout the corona radiata bilaterally with marked involvement of the brainstem and cervical spinal cord. Phylogenetic analyses of HPgV-1 showed clustering of brain-derived sequences from both patients with other human pegiviruses. In both patients, a novel 87-nucleotide deletion in the viral NS2 gene was detected. The presence of positive and negative strand HPgV-1 RNA and viral antigens in both patients indicated viral persistence and replication in the CNS. Autopsy showed lymphocyte infiltration and gliosis predominantly in white matter of the brain and brain stem but, to a lesser extent, also in grey matter. Immunofluorescence revealed HPgV-1 NS5A antigen in lymphocytes as well as in astrocytes and oligodendrocytes. Thus, we hypothesize that the novel deletion in the NS2 coding region may have caused HPgV-1 neuroadaptation or might represent a yet unrecognized genotype of human pegivirus.
This presentation will enable the learner to:
1. Describe the clinical and neuropathological features of fatal human pegivirus-associated encephalitis
2. Recognize the importance of molecular analysis in encephalitis cases with unknown etiology
The initial chemical composition of a proto-planetary nebula depends upon the degree to which 1) organic and ice components form on dust grains, 2) organic and molecular species form in the gas phase, 3) organics and ices are exchanged between the gas and solid state, and 4) the precursor and newly formed (more complex) materials survive and are modified in the developing planetary system. Infrared and radio observations of star-forming regions reveal that complex chemistry occurs on icy grains, often before stars even form. Additional processing, through the proto-planetary disk (PPD) further modifies most, but not all, of the initial materials. In fact, the modern Solar System still carries a fraction of its interstellar inheritance (Alexander et al.2017). Here we focus on three examples of small bodies in our Solar System, each containing chemical and dynamical clues to its origin and evolution: the small-cold classical Kuiper Belt object (KBO) 2014 MU69, Pluto, and Saturn’s moon, Phoebe. The New Horizons flyby of 2014 MU69 has given the first view of an unaltered body composed of material originally in the solar nebula at ~45 AU. The spectrum of MU69 reveals methanol ice (not commonly found), a possible detection of water ice, and the noteworthy absence of methane ice (Stern et al. 2019). Pluto’s internal and surface inventory of volatiles and complex organics, together with active geological processes including cryo-volcanism, indicate a surprising level of activity on a body in the outermost region of the Solar System, and the fluid that emerges from subsurface reservoirs may contain material inherited from the solar nebula (Cruikshank et al.2019a,b). Meanwhile, Saturn’s captured moon, Phoebe, carries high D/H in H2O (Clark et al. 2019) and complex organics (Cruikshank et al. 2008), both consistent with its formation in, and inheritance from, the outer region of the solar nebula. Together, these objects provide windows on the origin and evolution of our Solar System and constraints to be considered in future chemical and physical models of PPDs.
Although the reliable and valid Peritraumatic Distress Inventory (PDI–C) and Peritraumatic Dissociative Experiences Questionnaire (PDEQ) are useful for identifying adults at risk of developing acute and chronic posttraumatic stress disorder (PTSD), they have not been validated in school-aged children and their predictive values remain unknown in this population. This study aims to assess the psychometric properties of the children versions of these two measures (PDI-C and PDEQ-C) in a sample of French-speaking school-children.
One-hundred and thirty-three consecutive victims of road traffic accidents, aged 8–15 years, were recruited into this longitudinal study via the emergency room. The peritraumatic reactions were assessed at baseline and PTSD symptoms were assessed 1 month later.
Cronbach's alpha coefficients were 0.8 and 0.77 for the PDI-C and PDEQ-C, respectively. The 1-month test-retest correlation coefficient (n = 33) was 0.77 for both measures. The PDI-C demonstrated a two-factor structure while the PDEQ-C displayed a one-factor structure. As with adults, the two measures were intercorrelated (r = 0.52) and correlated with subsequent PTSD symptoms and diagnosis (r = 0.21–0.56; P < 0.05).
The children versions of the PDI and PDEQ are reliable and valid in children.
Internal sequences of Tn501(Hg) and Tn721(Tc) have been compared by hybridization. In spite of the difference in the resistance they code for, there is extensive homology between the two elements. This homology resides in the transposon-coded genes that are necessary for transposition and indicates that the elements are closely related.
Tholins are polymeric hydrogenated carbon nitrides formed from N2:CH4 mixtures exposed to electrical discharges. They are complex disordered solids, and their structural chemistry and formation processes are not yet fully understood. Tholins have been widely adopted as useful analogs of reddish organic solids associated with planetary bodies or in interstellar space (e.g., Titan's aerosols, reddish surfaces of outer objects, interstellar organics, etc.) for fitting astronomical observations. However, there has been little evidence to date that they in fact constitute pertinent model materials, i. e. with chemical structure/composition similar to those presumed to be present in planetary or interstellar organic solids. In this contribution, we first review recent advances made regarding the determination of composition and structure of tholins produced in the laboratory. They point to a high chemical selectivity in the range of functional groups present, the control of unsaturation by nitrogen, and the highly disordered character of the structures. In a second section, we discuss the relationship between chemistry and the optical properties of tholins, and we point out the lack of a unique relationship between the shape and strength of the visible absorption bands and the chemical composition or structure of the model tholins. The tholins exhibit similarities with HCN “polymers”, that are suspected to be present in cometary refractory dust. This points to the existence of possible similar polymerisation processes, and it suggests they could also be used as analogs of N-rich cometary organics. Laboratory-based studies of cometary dust might offer new insights on the “chemical relevancy” of tholins, as combined micro-analytical techniques will allow direct comparison of chemical information between the materials produced. In a third section we present recent results pertaining to the search for such compounds in cometary grains (Stardust grains, interplanetary dust particles - IDPs). We show that some N-rich spots in stratospheric IDPs are rich in cyanide species, but no tholin-like compounds or polymeric HCN have been detected to date.
This article reviews the extant twin studies employing magnetic resonance imaging data (MRI), with an emphasis on studies of populationbased samples. There have been approximately 75 twin reports using MRI, with somewhat under half focusing on typical brain structure. Of these, most are samples of adults. For large brain regions such as lobar volumes, the heritabilities of large brain volumes are consistently high, with genetic factors accounting for at least half of the phenotypic variance. The role of genetics in generating individual differences in the volumes of small brain regions is less clear, mostly due to a dearth of information, but rarely because of disagreement between studies. Multivariate analyses show strong genetic relationships between brain regions. Cortical regions involved in language, executive function, and emotional regulation appear to be more heritable than other areas. Studies of brain shape also show significant, albeit lower, genetic effects on population variance. Finally, there is evidence of significant genetically mediated relationships between intelligence and brain structure. At present, the majority of twin imaging studies are limited by sample sizes small by the standards of behavioral genetics; nevertheless the literature at present represents a pioneering effort in the pursuit of answers to many challenging neurobiological questions.
Several large studies have demonstrated that the liability to smoke cigarettes is strongly genetically influenced. However, the role of genetic and environmental risk factors in the use of other common forms of tobacco use has yet to be studied. Data on the regular use of cigarettes, cigars, pipes, dip (moist snuff), and chewing tobacco from 2634 male twins were analyzed with ACE structural equation models. Twin similarity for regular cigarette and dip use was largely genetic in origin. However, twin resemblance for chewing tobacco was just about equally the result of genes and shared environment, and twin similarity for use of pipes and cigars was entirely the result of shared environmental factors. Thus, the genetic influences on the liability for regular tobacco use appear to vary based on tobacco type. The causes for the use of different forms of tobacco are complex and worthy of further study.
The paper proposes a new biological method for assessing the quality of lakes. It is based on the comparison of littoral and profundal macroinvertebrate communities sampled in soft sediments. Two depths were sampled: one at the littoral zone (Zl = 2m) to define a littoral index (Bl ) related to the biogenic potential of the lake (quantitative data), the other at the deep zone (Zf = 0.66 Zmax) to define a taxonomic deficit index (Df ) connected with the quality of the water-sediment interface in deep zone (qualitative data). These two indexes were combined in a Lake Biotic Index (LBI), with a range from 0 to 20, which gives an evaluation of the biogenic capacity of a lake to the development of macroconsumer communities. Using the Bl and Df values any lake can be plotted on a typological graph which is helpfull to characterize lakes both quantitatively (oligo- to polybiotic) and qualitatively (eu- to dysbiotic). Lake Châlain (French Jura) is presented as an example of the method application with its macrofauna and the index calculation. Then, this lake was included in the typological graph with nine other French lakes studied using the same method. Each lake, characterized by its Bl, Df and LBI values, can be compared to the others in a typological scheme. The proposed indexes are discussed and bases for interpretation of the results are presented. The proposed classification of lakes gives an evaluation of their biogenic capacity concerning macroconsumers and can be usefully compared with other classifications, especially with trophic and sediment types, in functional studies as well as in lake diagnosis, in the context of the Water Framework Directive (Directive 2000/60/CE).
Dry etching of silver for the metallization in microelectronics is
investigated. Etching is performed using an electron-cyclotron-resonance
reactive-ion-beam-etching system (ECR-RIBE) in an Ar/CF4 or
Ar/CF4/O2 mixture. The etch characteristics are
strongly affected by ion energy (beam voltage and microwave energy); the
O2 concentration in the reactive mixture has only a small
effect. An anisotropic, smooth etch profile and clean surface are obtained.
Focused ion beam (FIB) and atomic force microscopy (AFM) have been used to
study the etched profile and the roughness, respectively.
The physical and electrical properties as well as thermal stability of
reactively sputtered titanium nitride (TiN) film serving as a diffusion
barrier was studied for silver (Ag) metallization. The thermal stability of
Ag/TiN metallizations on Si with 12-nm-thick TiN barriers, as-deposited and
after annealing at 300-650°C in N2/H2 for 30 min, was
investigated with sheet resistance measurement, X-ray diffraction, focused
ion beam-scanning electron microscopy, atomic force microscopy and X-ray
photoelectron spectroscopy. According to electrical measurement no change of
sheet resistance was found after annealing at 600°C, but an abrupt rise
appeared at 650°C annealing. There are two causes by which the Ag/TiN/Si
structure became degraded. One is agglomeration of the silver layer, and the
other is oxidation and diffusion which are also associated problems during
As a part of the Arcelor project concerning the prediction of the capability
(“ Évaluation Prévisionnelle des Capabilités ” project), models are developed to predict
the mechanical properties of austenitic stainless steel coils processed on the Ugine&ALZ
integrated cold rolling line LC2i. Two approaches are used: statistical models resulting
from an analysis of industrial databases, and physical based modelling accounting for the
recrystallization mechanism during the final annealing to estimate the mechanical behaviour
of the final product, including twinning and martensite induced transformation mechanisms.
The work leads to the prediction of the yield stress and the tensile strength along the
cold-rolled and annealed coil; the calculated mechanical values are in good agreement with
the measurement on samples taken from coils of AISI 304 grade (UGINOX 18-9 E).