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Solids ablate under laser irradiation, but experiments have not previously characterized the initiation of this process at ultrarelativistic laser intensities. We present first measurements of bulk ion velocity distributions as ablation begins, captured as a function of depth via Doppler-shifted x-ray line emission from two viewing angles. Bayesian analysis indicates that bulk ions are either nearly stationary or flowing outward at the plasma sound speed. The measurements quantitatively constrain the laser-plasma ablation mechanism, suggesting that a steplike electrostatic potential structure drives solid disassembly.

A new class of crystal shapes has been developed for x-ray spectroscopy of point-like or small (a few mm) emission sources. These optics allow for dramatic improvement in both achievable energy resolution and total throughput of the spectrometer as compared with traditional designs. This class of crystal shapes, collectively referred to as the Variable-Radii Spiral (VR-Spiral), utilize crystal shapes in which both the major and minor radii are variable. A crystal using this novel VR-Spiral shape has now been fabricated for high-resolution Extended X-ray Absorption Fine Structure (EXAFS) experiments targeting the Pb-L3 (13.0 keV) absorption edge at the National Ignition Facility. The performance of this crystal has been characterized in the laboratory using a microfocus x-ray source, showing that high-resolution high-throughput EXAFS spectra can be acquired using this geometry. Importantly, these successful tests show that the complex three-dimensional crystal shape is manufacturable with the required precision needed to realize the expected performance of better than 5 eV energy resolution while using a 30 mm high crystal. An improved generalized mathematical form for VR-Spiral shapes is also presented allowing improved optimization as compared to the first sinusoidal-spiral based design. This new formulation allows VR-Spiral spectrometers to be designed at any magnification with optimized energy resolution at all energies within the spectrometer bandwidth.

A high-resolution x-ray spectrometer was coupled with an ultrafast x-ray streak camera to produce time-resolved line shape spectra measured from hot, solid-density plasmas. A Bragg crystal was placed near laser-produced plasma to maximize throughput; alignment tolerances were established by ray tracing. The streak camera produced single-shot, time-resolved spectra, heavily sloped due to photon time-of-flight differences, with sufficient reproducibility to accumulate photon statistics. The images are time-calibrated by the slope of streaked spectra and dewarped to generate spectra emitted at different times defined at the source. The streaked spectra demonstrate the evolution of spectral shoulders and other features on ps timescales, showing the feasibility of plasma parameter measurements on the rapid timescales necessary to study high-energy-density plasmas.

The plasma membrane adenosine triphosphate (ATP) release channel pannexin 1 (PANX1) has been implicated in many physiological and pathophysiological processes associated with purinergic signaling, including cancer progression, apoptotic cell clearance, inflammation, blood pressure regulation, oocyte development, epilepsy and neuropathic pain. Here we present near-atomic-resolution structures of human and frog PANX1 determined by cryo-electron microscopy that revealed a heptameric channel architecture. Compatible with ATP permeation, the transmembrane pore and cytoplasmic vestibule were exceptionally wide. An extracellular tryptophan ring located at the outer pore created a constriction site, potentially functioning as a molecular sieve that restricts the size of permeable substrates. The amino and carboxyl termini, not resolved in the density map, appeared to be structurally dynamic and might contribute to narrowing of the pore during channel gating. In combination with functional characterization, this work elucidates the previously unknown architecture of pannexin channels and establishes a foundation for understanding their unique channel properties.

ATP7A and ATP7B, two homologous copper-transporting P1B-type ATPases, play crucial roles in cellular copper homeostasis, and mutations cause Menkes and Wilson diseases, respectively. ATP7A/B contains a P-type ATPase core consisting of a membrane transport domain and three cytoplasmic domains, the A, P, and N domains, and a unique amino terminus comprising six consecutive metal-binding domains. Here, we present a cryo–electron microscopy structure of frog ATP7B in a copper-free state. Interacting with both the A and P domains, the metal-binding domains are poised to exert copper-dependent regulation of ATP hydrolysis coupled to transmembrane copper transport. A ring of negatively charged residues lines the cytoplasmic copper entrance that is presumably gated by a conserved basic residue sitting at the center. Within the membrane, a network of copper-coordinating ligands delineates a stepwise copper transport pathway. This work provides the first glimpse into the structure and function of ATP7 proteins and facilitates understanding of disease mechanisms and development of rational therapies.

Evolution of the hot spot plasma conditions was measured using high-resolution x-ray spectroscopy at the National Ignition Facility. The capsules were filled with DD gas with trace levels of Kr and had either a high-density-carbon (HDC) ablator or a tungsten (W)-doped HDC ablator. Time-resolved measurement of the Kr Heβ spectra, absolutely calibrated by a simultaneous time-integrated measurement, allows inference of the electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. By matching the calculated hot spot emission using a collisional-radiative code to experimental observations, the hot spot size and areal density are determined. These advanced spectroscopy techniques further reveal the effect of W dopant in the ablator on the hot spot parameters for their improved implosion performance.

The National Ignition Facility (NIF) diagnostic instrument manipulator (DIM) - based high resolution (dHIRES) x-ray spectrometer was used to measure the time evolution of the electron density (n e) and temperature (T e) in the hot spot of four NIF compressed capsules with 25 ps time resolution during the ‘stagnation’ phase. The electron density was inferred by comparing the measured Stark broadening of the krypton (Kr) Heβ spectral complex with theoretical calculations that include ion dynamic effects, and the electron temperature was inferred by comparing the measured ratio of the intensity of a dielectronically excited Li-like Kr line to the intensity of the Kr Heβ resonance line with calculations using the spectroscopic collisional radiative atomic model (SCRAM) and CRETIN collisional-radiative models. The inferred, time averaged n e values mainly agree with n e values from neutron diagnostics within uncertainties, but the neutron time-of-flight values of T ion are consistently higher than dHIRES T e values by 200–700 eV. The dHIRES measurements and measurement techniques, method of uncertainty analysis, and discussion of comparisons with measurements from neutron diagnostics are presented.

We measured the spectral emission of plasmas from the National Spherical Tokamak Experiment in the extreme ultraviolet region, typically dominated by M-shell iron lines. Although we found that most of the significant emission in the 170–270 A region emanates from iron, there are also some strong lines of carbon present. We show that the carbon lines are not produced by electron-impact excitation, and we speculate that they are formed instead by charge exchange.

Aims To compare regional brain activation among adolescents with bipolar disorder and co-occurring cannabis use disorder. Design Cross-sectional study. Setting Cincinnati, OH, USA. Participants Adolescents with bipolar disorder (BP, n = 14), adolescents with cannabis use disorder (MJ, n = 13), adolescents with co-occurring cannabis use and bipolar disorders (BPMJ, n = 25) and healthy adolescents (HC, n = 15). Measurements Cannabis craving, substance use, Blood Oxygenation Level Dependent (BOLD) signal assessed by the Marijuana Craving Questionnaire (MCQ), Teen-Addiction Severity Index (T-ASI) and a cannabis cue–reactivity task during a functional magnetic resonance imaging (fMRI) session, respectively. Findings The BP group exhibited significantly greater brain activation than the BPMJ group in the right amygdala (F = 4.14, P = 0.046), left nucleus accumbens (F = 3.8, P = 0.02), left thalamus (F = 3.8, P

Bipolar and cannabis use disorders commonly co-occur during adolescence, and neurochemical studies may help clarify the pathophysiology underlying this co-occurrence. This study compared metabolite concentrations in the left ventral lateral prefrontal cortex among adolescents with bipolar disorder (bipolar group; n = 14), adolescents with a cannabis use disorder (cannabis use group; n = 13), adolescents with cannabis use and bipolar disorders (bipolar and cannabis group; n = 25), and healthy adolescents (healthy controls; n = 15). We hypothesized that adolescents with bipolar disorder (with or without cannabis use disorder) would have decreased N-acetyl aspartate levels in the ventral lateral prefrontal cortex compared to the other groups and that the bipolar and cannabis group would have the lowest N-acetyl aspartate levels of all groups.N-acetyl aspartate concentrations in the left ventral lateral prefrontal cortex were obtained using proton magnetic resonance spectroscopy.Adolescents with bipolar disorder showed significantly lower left ventral lateral prefrontal cortex N-acetyl aspartate levels, but post hoc analyses indicated that this was primarily due to increased N-acetyl aspartate levels in the cannabis group. The cannabis use disorder group had significantly higher N-acetyl aspartate levels compared to the bipolar disorder and the bipolar and cannabis groups (p = .0002 and p = .0002, respectively). Pearson correlations revealed a significant positive correlation between amount of cannabis used and N-acetyl aspartate concentrations.Adolescents with cannabis use disorder showed higher levels of N-acetyl aspartate concentrations that were significantly positively associated with the amount of cannabis used; however, this finding was not present in adolescents with comorbid bipolar disorder.

We observe and study the phenomenon of Anderson localization in a system of true quantum kicked rotors. Nitrogen molecules in a supersonic molecular jet are cooled down to 27~K and are rotationally excited by a periodic train of 24~high-intensity femtosecond pulses. Exponential distribution of the molecular angular momentum - the most unambiguous signature of Anderson localization - is measured directly by means of coherent Raman scattering. We demonstrate the suppressed growth of the molecular rotational energy with the number of laser kicks and study the dependence of the localization length on the kick strength. Both timing and amplitude noise in the pulse train is shown to destroy the localization and revive the diffusive growth of angular momentum., 4 figures

We experimentally demonstrate coherent control of a quantum system, whose dynamics is chaotic in the classical limit. Interaction of diatomic molecules with a periodic sequence of ultrashort laser pulses leads to the dynamical localization of the molecular angular momentum, a characteristic feature of the chaotic quantum kicked rotor. By changing the phases of the rotational states in the initially prepared coherent wave packet, we control the rotational distribution of the final localized state and its total energy. We demonstrate the anticipated sensitivity of control to the exact parameters of the kicking field, as well as its disappearance in the classical regime of excitation., Comment: 5 figures

We experimentally study a system of quantum kicked rotors - an ensemble of diatomic molecules exposed to a periodic sequence of ultrashort laser pulses. In the regime, where the underlying classical dynamics is chaotic, we investigate the quantum phenomenon of dynamical localization by means of state-resolved coherent Raman spectroscopy. We examine the dependence of the exponentially localized angular momentum distribution and of the total rotational energy on the time period between the pulses and their amplitude. The former parameter is shown to provide control over the localization center, whereas the latter one controls the localization length. Similar control of the center and width of a nonlocalized rotational distribution is demonstrated in the limit of classical diffusion, established by adding noise to the periodic pulse sequence., Comment: 6 figures

Objective Although previous neuroimaging studies suggest that adolescents with bipolar disorder exhibit smaller amygdala volumes compared with healthy adolescents, whether these abnormalities are present at illness onset or instead develop over time remains unclear. The aim of this study was to conduct a prospective longitudinal investigation comparing amygdala neurodevelopment among adolescents after their first manic episode, adolescents with attention-deficit/hyperactivity disorder (ADHD), and healthy adolescents. Method A total of 30 adolescents hospitalized for their first manic/mixed episode associated with bipolar disorder, 29 adolescents with ADHD, and 24 demographically matched healthy teens underwent magnetic resonance imaging scanning at index assessment and approximately 12 months later. Adolescents with bipolar disorder were prospectively evaluated using diagnostic interviews and with symptom rating scales. Results Mixed models examining the group × time effect for both left ( p = .005) and right ( p = .002) amygdala volumes were statistically significant. Change in left ( p = .01) and right ( p = .0008) amygdala volumes from baseline to 12 months were significantly different among groups. Specifically, left amygdala volumes increased over time in healthy adolescents ( p = .008) and adolescents with ADHD ( p = .0009), but not in adolescents with bipolar disorder ( p = .3). Right amygdala volume increased over time in adolescents with ADHD ( p p = .1 and p = .3, respectively). In adolescents with bipolar disorder, baseline total amygdala volume was significantly greater in those who subsequently achieved symptomatic recovery as compared with those who did not achieve recovery ( p = .02). Conclusions Adolescents with mania do not exhibit normal increases in amygdala volume that occur during healthy adolescent neurodevelopment.

Aims: To examine the prevalence of trauma exposure as well as the rates and effects of post-traumatic stress disorder (PTSD) in adolescents with bipolar disorder following a first manic episode. Methods: Adolescents (12–18 years) with DSM-IV bipolar I disorder and experiencing their first manic or mixed episode were recruited. Participants underwent structured diagnostic interviews, completed the Trauma Symptom Checklist for Children (TSCC), and were prospectively evaluated using diagnostic, symptomatic and functional assessments over the course of 12 months. Results: Seventy-six adolescents (14.9 ± 1.7 years) completed the TSCC and 66% (50 individuals) reported exposure to traumatic events. Two (3%) subjects met DSM-IV criteria for PTSD, 11 (14%) had post-traumatic stress t-scores ≥65, the threshold for clinically significant symptoms. Subjects with and without post-traumatic stress t-scores ≥65 did not differ in demographic characteristics. When compared by t-score, TSCC subscores of the first episode bipolar adolescents were similar to normative data. Regression models incorporating TSCC subcomponents, did not predict syndromic recovery or recurrence or symptomatic recovery. Conclusions: Rates of PTSD were lower in this sample of bipolar adolescents at the time of their first hospitalization compared with rates in samples of bipolar adults. These differences coupled with the low incidence of PTSD and trauma symptoms in this young sample suggests that bipolar disorder may be a risk factor for the development of PTSD later in the course of illness or following recurrent affective episodes.

The definitive version is available at www.blackwell-synergy.com Please cite this as: Van Rosmalen, P., Sloep, P.B, Brouns, F., Kester, L., Berlanga, A., Bitter, M., Koper, R. (2008). A model for online learner support based on selecting appropriate peer tutors. Journal of Computer Assisted Learning 24, 483–493. Available online at doi: 10.1111/j.1365-2729.2008.00283.x

Night-time chemistry in the Marine Boundary Layer has been modelled using a number of observationally constrained zero-dimensional box-models. The models were based upon the Master Chemical Mechanism (MCM) and the measurements were taken during the North Atlantic Marine Boundary Layer Experiment (NAMBLEX) campaign at Mace Head, Ireland in July–September 2002. The model could reproduce, within the combined uncertainties, the measured concentration of HO2 (within 30–40%) during the night 31 August–1 September and of HO2+RO2 (within 15–30%) during several nights of the campaign. The model always overestimated the NO3 measurements made by Differential Optical Absorption Spectroscopy (DOAS) by up to an order of magnitude or more, but agreed with the NO3 Cavity Ring-Down Spectroscopy (CRDS) measurements to within 30–50%. The most likely explanation of the discrepancy between the two instruments and the model is the reaction of the nitrate radical with inhomogeneously distributed NO, which was measured at concentrations of up to 10 ppt, even though this is not enough to fully explain the difference between the DOAS measurements and the model. A rate of production and destruction analysis showed that radicals were generated during the night mainly by the reaction of ozone with light alkenes. The cycling between HO2/RO2 and OH was maintained during the night by the low concentrations of NO and the overall radical concentration was limited by slow loss of peroxy radicals to form peroxides. A strong peak in [NO2] during the night 31 August–1 September allowed an insight into the radical fluxes and the connections between the HOx and the NO3 cycles.

We investigate the prospects of creating broad rotational wave packets by means of molecular interaction with long sequences of intense femtosecond pulses. Using state-resolved rotational Raman spectroscopy of oxygen, subject to a sequence of more than 20 laser pulses with peak intensities exceeding ${10}^{13}\phantom{\rule{4.pt}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$ per pulse, we show that the centrifugal distortion is the main obstacle on the way to reaching high rotational states. We demonstrate that the timing of the pulses can be optimized to partially mitigate the centrifugal limit. The cumulative effect of a long pulse sequence results in a high degree of rotational coherence, which is shown to cause an efficient spectral broadening of probe light via cascaded Raman transitions.

Purpose : To determine differences in patient’s reported quality of life and self-reported breast cosmesis between whole breast radiation therapy (WBRT) and accelerated partial breast irradiation (APBI) via single and multi-lumen high-dose-rate (HDR) brachytherapy for women with early stage breast cancer. Material and methods: Patient information was retrospectively reviewed and survey data were prospectively collected for women treated between 2004 to 2014 (APBI) and 2012 to 2014 (WBRT). Criteria for APBI treatments were ER+ (after 2010), N0 (after 2010), T < 3 cm, and post-menopausal. All patients were given a survey with modified FACIT (Functional Assessment of Chronic Illness Therapy) breast quality of life questions to rate their amount of pain, self-consciousness, low energy, presence of lymphedema, and breast cosmesis. Results : 242 APBI patients and 59 WBRT patients were identified. In the WBRT cohort, 34 women met departmental criteria for APBI treatment (WBRT who were APBI eligible). The FACIT survey was completed by 80 women treated with APBI (33%; mean follow-up time of 14 months), and 26 women treated with WBRT who were APBI eligible (76%; mean follow-up time of 26 months). During the first year post-treatment, low energy (p = 0.009), self-consciousness (p = 0.0004), and lymphedema (p = 0.0002) scores were significantly lower in the APBI cohort when compared to women treated with WBRT who were APBI eligible. During the second year post-treatment, women treated with APBI reported significantly better breast cosmesis (p = 0.04). The single-lumen balloon (score = 6.3/10) was found to be associated with worse cosmesis compared to the multi-lumen balloons (Mammosite ML and Contura; score = 8.2/10; p = 0.002). There were no significant differences in rates of recurrence between balloons or treatments (p > 0.05). Conclusions : APBI treated patients reported higher cosmetic satisfaction than patients in the matched WBRT cohort. Quality of life scores tended to improve over time. Multi-lumen catheters provided superior cosmetic results compared to single-lumen catheters.

This paper describes a broadband cavity ringdown spectrometer and its deployment during the 2002 North Atlantic Marine Boundary Layer Experiment (NAMBLEX) to measure ambient concentrations of NO3, N2O5, I2 and OIO at the Mace Head Atmospheric Research Station, Co. Galway, Ireland. The effective absorption path lengths accessible with the spectrometer generally exceeded 10 km, enabling sensitive localised ``point' measurements of atmospheric absorbers to be made adjacent to the other instruments monitoring chemically related species at the same site. For the majority of observations, the spectrometer was used in an open path configuration thereby avoiding surface losses of reactive species. A subset of observations targeted the N2O5 molecule by detecting the additional NO3 formed by the thermal dissociation of N2O5. In all cases the concentrations of the atmospheric absorbers were retrieved by fitting the differential structure in the broadband cavity ringdown spectra using a methodology adapted from long path differential optical absorption spectroscopy. The uncertainty of the retrieval depends crucially on the correct treatment and fitting of the absorption bands due to water vapour, a topic that is discussed in the context of analysing broadband cavity ringdown spectra. The quality of the measurements and the retrieval method are illustrated with representative spectra acquired during NAMBLEX in spectral regions around 660 nm (NO3 and N2O5) and 570 nm (I2 and OIO). Typical detection limits were 1 pptv for NO3 in an integration time of 100 s, 4 pptv for OIO and 20 pptv for I2 in an integration time of 10 min. Additionally, the concentrations of atmospheric water vapour and the aerosol optical extinction were retrieved in both spectral regions. A companion paper in this issue presents the time series of the measurements and discusses their significance for understanding the variability of short lived nitrogen and iodine compounds in the marine boundary layer.

This preliminary study investigated the neurofunctional effects of carbamazepine-extended release (XR) treatment in 11 manic youth with bipolar disorder during performance of a sustained attention task, the Continuous Performance Task – Identical Pairs version (CPT-IP), during functional magnetic resonance imaging (fMRI). All patients underwent baseline fMRI, and 10 patients were scanned again at endpoint. Nine demographically matched healthy youth, who were scanned once, served as controls. Carbamazepine-XR treatment was associated with normalization of activation in right Brodmann area 10 (BA). These results suggest that carbamazepine-XR treatment may correct prefrontal dysfunction in adolescent mania.

Research in NSTX has been conducted to establish spherical torus plasmas to be used for high ?, auxiliary heated experiments. This device has a major radius R0 = 0.86?m and a midplane halfwidth of 0.7?m. It has been operated with toroidal magnetic field B0 ? 0.3?T and Ip ? 1.0?MA. The evolution of the plasma equilibrium is analysed between discharges with an automated version of the EFIT code. Limiter, double null and lower single null diverted configurations have been sustained for several energy confinement times. The plasma stored energy reached 92?kJ (?t = 17.8%) with neutral beam heating. A plasma elongation in the range 1.6 ? ? ? 2.0 and a triangularity in the range 0.25 ? ? ? 0.45 have been sustained, with values of ? = 2.6 and ? = 0.6 being reached transiently. The reconstructed magnetic signals are fitted to the corresponding measured values with low errors. Aspects of the plasma boundary, pressure and safety factor profiles are supported by measurements from non-magnetic diagnostics. Plasma densities have reached 0.8 and 1.2 times the Greenwald limit in deuterium and helium plasmas, respectively, with no clear limit encountered. Instabilities including sawteeth and reconnection events, characterized by Mirnov oscillations, and a perturbation of the Ip, ? and li evolutions, have been observed. A low q limit was observed and is imposed by a low toroidal mode number kink instability.

The mission of the National Spherical Torus Experiment (NSTX) is to extend the understanding of toroidal physics to low aspect ratio (R/a approximately equal to 1.25) in low collisionality regimes. NSTX is designed to operate with up to 6 MW of High Harmonic Fast Wave (HHFW) heating and current drive, 5 MW of Neutral Beam Injection (NBI) and Co-Axial Helicity Injection (CHI) for non-inductive startup. Initial experiments focused on establishing conditions that will allow NSTX to achieve its aims of simultaneous high-bt and high-bootstrap current fraction, and to develop methods for non-inductive operation, which will be necessary for Spherical Torus power plants. Ohmic discharges with plasma currents up to 1 MA and with a range of shapes and configurations were produced. Density limits in deuterium and helium reached 80% and 120% of the Greenwald limit respectively. Significant electron heating was observed with up to 2.3 MW of HHFW. Up to 270 kA of toroidal current for up to 200 msec was produced noninductively using CHI. Initial NBI experiments were carried out with up to two beam sources (3.2 MW). Plasmas with stored energies of up to 140 kJ and bt =21% were produced.

A monolithically integrated and fully packaged Mach–Zehnder interferometer with semiconductor optical amplifiers (MZI-SOA) is demonstrated as polarisation-independent high-speed demultiplexer for up to 160 Gbit/s optical time division multiplexed (OTDM) data streams.

We describe an advanced InP-InGaAs-based technology for the monolithic integration of pin-photodiodes and SHBT-transistors. Both devices are processed using the same epitaxial grown layer structure. Employing this technology, we have designed and fabricated two photoreceivers achieving transimpedance gains of 170 /spl Omega//380 /spl Omega/ and optical/electrical bandwidths of 50 GHz/34 GHz. To the best of our knowledge, this is the highest bandwidth of any heterojunction bipolar transistor (HBT)-based photoreceiver optoelectronic integrated circuit (OEIC) published to date. We even predict a bandwidth of 60 GHz for the same circuit topology by a simple reduction of the photodiode diameter and an adjustment of the feedback resistor value.

To compare regional brain activation among adolescents with bipolar disorder and co-occurring cannabis use disorder.Cross-sectional study.Cincinnati, OH, USA.Adolescents with bipolar disorder (BP, n = 14), adolescents with cannabis use disorder (MJ, n = 13), adolescents with co-occurring cannabis use and bipolar disorders (BPMJ, n = 25) and healthy adolescents (HC, n = 15).Cannabis craving, substance use, Blood Oxygenation Level Dependent (BOLD) signal assessed by the Marijuana Craving Questionnaire (MCQ), Teen-Addiction Severity Index (T-ASI) and a cannabis cue-reactivity task during a functional magnetic resonance imaging (fMRI) session, respectively.The BP group exhibited significantly greater brain activation than the BPMJ group in the right amygdala (F = 4.14, P = 0.046), left nucleus accumbens (F = 3.8, P = 0.02), left thalamus (F = 3.8, P 0.05) and the right thalamus (F = 6.2, P = 0.02). The BP group exhibited significantly greater activation than the HC group in the left nucleus accumbens (F = 11.5, P = 0.0001), right thalamus (F = 4.9, P = 0.03) and the left striatum (F = 3.6, P = 0.04). Left amygdala activation of the BPMJ group trended towards being significantly negatively correlated with the number of joints smoked (R = -0.4, P = 0.06).Bipolar adolescents with comorbid cannabis use do not exhibit the same over-activation of the regions involved in emotional processing as seen in adolescents with bipolar disorder alone. The absence of these findings in patients with comorbid bipolar and cannabis use disorders suggests that these individuals may have a unique endophenotype of bipolar disorder or that cannabis use may alter brain activation uniquely in bipolar disorder patients who use cannabis.

OBJECTIVE: Depressive and anxiety disorders are common in youth who are at risk for bipolar disorder (i.e., youth who have at least one parent with bipolar disorder) and antidepressants are commonly prescribed as treatment. However, there are few data regarding the safety and tolerability of antidepressants in this population. Therefore, we sought to prospectively examine the effects of these medications in children and adolescents who are diagnosed with depressive or anxiety disorders and have a parent with bipolar I disorder. METHODS: Youth aged 9-20 years, with at least one parent with bipolar I disorder [high risk (HR)], were recruited (n = 118) and assessed using semi-structured diagnostic interviews. Participants were prospectively evaluated using a modified version of the Longitudinal Interval Follow-up Evaluation to assess changes in affective and anxiety symptoms and were treated naturalistically. RESULTS: Over the course of 43-227 weeks (mean duration of follow-up: 106 ± 55 weeks), 21% (n = 25) of youth had antidepressant exposure and, of these, 57% (n = 12) had an adverse reaction (e.g., irritability, aggression, impulsivity, or hyperactivity) that led to antidepressant discontinuation. Those patients who experienced an adverse reaction were significantly younger than those who did not (p = 0.02) and discontinuation of antidepressant therapy secondary to an adverse event occurred at an average of 16.7 ± 17.4 weeks (median: 11 weeks, range: 2-57 weeks). Cox proportional hazard analyses yielded a hazard ratio of 0.725 (p = 0.03), suggesting that there is a 27% decrease in the likelihood of an antidepressant-related adverse event leading to discontinuation with each one-year increase in age. CONCLUSIONS: Antidepressant medications may be poorly tolerated in youth with a familial risk for developing mania. Controlled studies further assessing treatments for depression and anxiety in HR youth are urgently needed. Language: en

Current mode operation of the NE451 ZnS scintillation detectors of the TFTR neutron collimator has enabled us to record the development of radial neutron emission profiles with much faster speed and higher accuracy than in the pulse counting mode. During high power deuterium–tritium (DT) operation, the intrinsic shot noise on the detector traces was so low that we could observe sawtooth instabilities and disruptions with good precision and, in addition, were able to identify precursor magnetohydrodynamic (MHD) activity and fishbone instabilities. These results demonstrate that in future tritium burning machines like ITER or TPX, the neutron collimator should be designed not only as a monitor of radial fusion power profiles but also as a wave detector for MHD activity.

We report on the device fabrication and measured performance of p-i-n photodiodes made from wafer-bonded InGaAs-on-Si material. Dark currents below 38 pA and 3-dB bandwidths above 11 GHz were measured for a -4-V bias and for an active area diameter of 20 /spl mu/m. The thermal conductivity of silicon enables a 200-MHz 1-dB compression current of 76.5 mA, measured on nonoptimized test devices. These devices dissipate upwards of 612 mW of electrical power. High-yield wafer-scale fabrication of InGaAs-on-Si p-i-n photodetectors is demonstrated.

The engineering design for two high-resolution x-ray imaging crystal spectrometers for KSTAR tokamak has been completed. A spherically bent quartz crystal and a large area two-dimensional (2D) position-sensitive multiwire proportional counter have been selected for the imaging spectrometers. A prototype 10 cm by 30 cm 2D detector was fabricated and pilot measurement on Alcator C-Mod tokamak was carried out. The final engineering design of the spectrometers and experimental results from the 2D detector are presented.

In this letter, an InGaAs-on-Si single photon avalanche diode (SPAD) for telecommunication wavelengths is presented. This SPAD demonstrates high-single-photon quantum efficiency and low-dark-count probability under gated mode operation. We attributed the good performance of this device to the high absorption coefficient of InGaAs and low noise avalanche multiplication of Si.

This article describes a new x-ray imaging Bragg crystal spectrometer, which-in combination with a streak camera or a gated strip detector-can be used for time-resolved measurements of x-ray line spectra at the National Ignition Facility and other high power laser facilities. The main advantage of this instrument is that it produces perfect images of a point source for each wavelength in a selectable spectral range and that the detector plane can be perpendicular to the crystal surface or inclined by an arbitrary angle with respect to the crystal surface. These unique imaging properties are obtained by bending the x-ray diffracting crystal into a certain shape, which is generated by arranging multiple cones with different aperture angles on a common nodal line.

An inversion technique is presented to calculate local toroidal and poloidal rotation velocity and ion temperature from line-integrated measurements of impurity lines by a matrix method. The effects of the rotation velocity on the ion temperature are analyzed in particular. An accurate inversion formula for the ion temperature is obtained. Several experimental geometries or configurations of line-integrated diagnostics in tokamaks are presented. For a plasma that is up-down symmetric, both the toroidal rotation velocity and poloidal rotation velocity can be deduced from one special line-integrated measurement.

Prior research has found that manic adolescents with bipolar disorder exhibit neurofunctional changes in the amygdala and prefrontal cortex following treatment with some pharmacological agents. We examined the neurofunctional effects of ziprasidone in manic adolescents.Manic adolescents with bipolar disorder (n=23) participated in a placebo-controlled study of ziprasidone and underwent a functional magnetic resonance imaging scanning session while performing a task of sustained attention at baseline, prior to treatment as well as on days 7 and 28 (or early termination) of treatment. A comparison group of healthy adolescents (n=10) participated in a single scanning session. Region of interest analyses were performed to assess activation changes associated with treatment in Brodmann Areas (BA) 10, 11 and 47 and in the amygdala.Compared with placebo, treatment with ziprasidone was associated with greater increases over time in right BA 11 and 47 activation. These effects were not associated with differences in symptom improvement between the treatment groups. Patients who subsequently responded to ziprasidone showed significantly greater deactivation in the right Brodmann area 47 at baseline than those who did not respond to ziprasidone. Similarly, among the bipolar adolescents who were treated with ziprasidone, baseline activation in right BA 47 was negatively correlated with improvement in Young Mania Rating Scale (YMRS) score.The small sample size limits the ability to detect significant group differences in other regions of interest. Healthy comparison subjects were scanned only at a single timepoint, which limits the interpretation of the results. Ziprasidone is not currently approved by the United States Food and Drug Administration for the treatment of adolescents with mania, and, therefore, the clinical relevance of these results is limited.The increases in right BA 11 and 47 activation observed during sustained attention tasks following ziprasidone treatment and the association identified between lower baseline BA 47 activation and ziprasidone treatment response suggests that ziprasidone may correct prefrontal dysfunction in manic adolescents with bipolar disorder.

We have been making spectral measurements in the extreme ultraviolet (EUV) from different laboratory sources in order to investigate the electron density dependence of various astrophysically important emission lines and to test the atomic models underlying the diagnostic line ratios. The measurement are being performed at the Livermore EBIT-I electron beam ion trap, the National Spherical Torus Experiment (NSTX) at Princeton, and the Alcator C-Mod tokamak at the Massachusetts Institute of Technology, which together span an electron density of four orders of magnitude and which allow us to test the various models at high and low density limits. Here we present measurements of Fe XXII and Ar XIV, which include new data from an ultra high resolution (λ/Δλ >4000) spectrometer at the EBIT-I facility. We found good agreement between the measurements and modeling calculations for Fe XXII, but poorer agreement for Ar XIV.

We report an experimental and theoretical study of the evolution of vibrational coherence in a thermal ensemble of nitrogen molecules. Rotational dephasing and rephasing of the vibrational coherence is detected by coherent anti-Stokes Raman scattering. The existence of ro-vibrational coupling and the discrete energy spectrum of the rotational bath lead to a whole new class of full and fractional ro-vibrational revivals. Following the rich ro-vibrational dynamics on a nanosecond time scale with sub-picosecond time resolution enables us to determine the second-order ro-vibrational constant $gamma_e$ and assess new possibilities of controlling decoherence., Comment: submitted at Physical Review A