Warm and thick corona for magnetically supported disk in GBHB

This paper is devoted to self-consistent modeling of the magnetically supported accretion disk with optically thick warm corona based on first principles. In our model, we consider the gas heating by magneto-rotational instability (MRI) dynamo. Our goal is to show that the proper calculation of the gas heating by magnetic dynamo can build up the warm, optically thick corona above the accretion disk around black hole of stellar mass. Using vertical model of the disk supported and heated by the magnetic field together with radiative transfer in hydrostatic and radiative equilibrium we developed relaxation numerical scheme which allows us to compute the transition form the disk to corona in a self consistent way. We demonstrate here that the warm (up to 5 keV), optically thick (up to 10 Thompson optical depths), Compton cooled corona can form due to the magnetic heating. Such warm corona is stronger for higher accretion rate and larger magnetic field strength. The radial extent of the warm corona is limited by the occurrence of the local thermal instability, which purely depends on radiative processes. The obtained coronal parameters are in agreement with those constrained from X-ray observations. The warm magnetically supported corona is tends to appear in the inner disk regions. It may be responsible for Soft X-ray excess seen in accreting sources. For lower accretion rates and weaker magnetic field parameters, thermal instability prevents warm corona to exist, giving rise to eventual clumpiness or ionized outflow.Comment: accepted for publication in A&A on 4 Sep 201

Arms down cone beam CT hepatic angiography: are we focusing on the wrong target?

We read with great interest the recent article by Dr. Gonzalez-Aguirre and colleagues entitled ‘‘Arms Down Cone Beam CT Hepatic Angiography Performance Assessment: Vascular Imaging Quality and Imaging Artefacts’’ [1]. One of the most important advantages of cone beam CT (CBCT) is the possibility to evaluate the lesion’s feeders assisting their identification and catheterization [2]. In this set, the patient’s arms positioning is crucial in order not to impair CBCT imaging. Dr. Gonzalez-Aguirre et al. had elegantly demonstrated that vessels’ visualization is independent from the patient’s arms position, allowing to perform the entire procedure without patient’s movements. This minimizes the risk of contamination and reduces procedural time. However, literature shows that the major pivotal strength of CBCT, either mono-phasic or possibly bi-phasic, is the ability to depict in intra-procedurally ‘‘occult lesions’’, not visible at pre-procedural second-line non-invasive imaging (MRI, MDCT) [3]. This ability is not just for show, but yield to some major clinical implications: the visualization of an occult nodule identifies a subset of population experiencing fast tumour growth, having consequences on the number of adjunctive treatments controlling tumour growth (adjunctive RFA, or TACE procedures) and prioritization for transplantation [4]. Moreover, bi-phasic CBCT, with its unique ability to intra-procedural permit nodule characterization, could help in patients’ reclassification and real-time TACE strategy modification [5]. In this light would be a crucial interest for the audience to know whether the CBCT acquisition with arms down does not alter the diagnostic performance of the modality and ability of lesion’s characterization, especially for those lesion localized peripherally, where the beam hardening artefacts have been shown to be significant. Finally, patient’s positioning is fundamental for CBCT imaging. By acquiring the scan with patient’s arm down, liver volume would not be located within the rotation isocentre. This could be a substantial limitation for lesion located within the left liver lobe, eventually hypertrophied, and for high BMI patients

Thermally damped linear compressional waves in a 2D solar coronal model

The high resolution observations (TRACE and SOHO) of waves in coronal structures have revealed a rapid damping of modes, sometimes their damping length being of the same order as their wavelength. The rapid damping of modes in coronal loops permits us to derive values for magnetic field and transport coefficients. In this contribution we study the damping of linear compressional waves considering a two-dimensional propagation in gravitationally stratified plasma in the presence of thermal conduction. By considering this 2D model, we show that the presence of an additional transversal motion has an important effect on the damping of the waves. This theoretical model allows as to conclude that the main effects influencing the damping of the waves are the degree of the transversal structuring and temperature

Devices and architectures for large scale integrated silicon photonics circuits

We present DWDM nanophotonics architectures based on microring resonator modulators and detectors. We focus on two implementations: an on chip interconnect for multicore processor (Corona) and a high radix network switch (HyperX). Based on the requirements of these applications we discuss the key constraints on the photonic circuits' devices and fabrication techniques as well as strategies to improve their performance

Predictors of Therapists Use of Homework in Community Mental Health: Session and Therapist Characteristics

Assigning and reviewing homework as a strategy to help clients gain therapeutic skills is a common technique used across a variety of evidence-based practices (EBPs) and has been shown to improve therapy outcomes for children and youth. However, in studies characterizing routine psychotherapy delivered in community mental health settings, homework is rarely used in sessions. While some therapist and client level predictors of EBP strategy use have been identified in routine psychotherapy (e.g. client stressors, therapists’ attitudes towards EBPs) it is unknown what is associated with community mental health therapists using homework in the increasingly common context of system-driven implementation of multiple EBPs. To identify predictors of therapists’ use of homework, 680 videos of sessions with 274 clients were collected from 103 therapists (of which 55% were Hispanic) providing children’s mental health services through the Los Angeles County Department of Mental Health (LACDMH). The current study uses a multilevel logistic regression analysis model to identify which factors are associated with therapist use of homework in therapy sessions when there is system-driven implementation support for the use of multiple EBPs in community mental health settings. After controlling for the EBP delivered in session and the number of EBPs therapists were trained in, having a caregiver present in the therapy session, older child age, and being an unlicensed therapist were associated with a higher likelihood of therapists assigning and reviewing homework during a specific session. Therapist race/ethnicity, perceptions of the EBP being delivered, their report of emotional exhaustion, and direct hours with clients, as well as emergent unexpected stressful client life events within a session were not significantly associated with therapists’ delivery of homework. These findings underscore the need to provide explicit attention during therapist training on the use of homework with younger clients when caregivers are absent from sessions and the need to facilitate the use of homework among licensed therapists

The mean ionic charges of N, Ne, MG, SI and S in solar energetic particle events

The mean ionic charges of nitrogen, neon, magnesium, silicon, and sulfur in solar flare particle events were determined for 12 flares during the time interval from September 1978 to September 1979. The observations were carried out with the MPI/UoMd ULEZEQ Sensor on the ISEE-3 satellite comparing the results with mean charge states established in a hot coronal plasma under equilibrium conditions, different temperatures for different elements are discussed. These range from approx. 2 million K to 7 million K in a single flare. From flare to flare the variation in temperature for each element is less than the variation between different ion species

On the Specification of Coronals

Ens ocupem de la relació entre les asimetries en les possibilitats en els processos d'assimilació en català central i el caràcter subespecificat de Coronal. Expliquem aquestes asimetries en el comportament assimilatori de les consonants situant Lateral i Estrident sota Coronal. Assumim així que aquests trets depenen de Coronal i que això justifica la presència de l'articulador nomarcat a les representacions subjacents de les coronals lateral i estrident. Les possibilitats assimilatòries de les consonants centralitzades de l'alguerès ens porten a argumentar que Lateral i Estrident són trets doblement lligats. Considerem una anàlisi alternativa que es basa en Restriccions de Configuració i demostrem que aquesta anàlisi no pot explicar els processos de semivocalització que afecten alguns segments complexos en mallorquí i en occità. L'organització dels trets ens permet donar una explicació simple i unitaris, així seguim l'estratègia habitual per aconseguir que l'enriquiment de les representacions derivi en una simplificació del component de les regles.We present the relation between assimilatory asymmetries in Central Catalan and the underspecified character of Coronal. We account for differences in the assimilatory behaviour of coronals by placing Lateral and Strident under Coronal. We assume that these features are dependents of Coronal and that this justifies the presence of the unmarked articulator in the underlying representations of sirident and lateral coronals. The assimilatory possibilities of centralised consonants in Alguerese Catalan force us to argue that Lateral and Strident are double-linked features. We consider an altemative analysis based on Configurational Constraints and we demonstrate that this analysis fails to capture the gliding processes which affect some complex segments in Majorcan Catalan and Occitan. The organisation of features allows us to provide a simple and unitary account, in this way the enrichrnent of the representations derives in a simplification de component