Introduction to Group Interventions for Trauma Survivors Foy, David W; Eriksson, Cynthia B; Trice Headington Program in International Trauma Fuller Theological Seminary, Gary A
Group dynamics,
12/2001, Volume:
5, Issue:
4
Journal Article
Peer reviewed
Group interventions for trauma survivors offer cost-efficient opportunities for members to join "fellow strugglers" in coping with trauma-related feelings of alienation and mistrust. For adults, ...supportive, psychodynamic, and cognitive-behavioral models have been described in the literature, each offering common as well as unique group therapy features. For older children and adolescents, integrated and cognitive-behavioral models are available, and there is general empirical support for the use of group therapy regardless of the model chosen. Group psychological debriefing immediately following trauma exposure may be useful for normalizing reactions, but evidence for its effectiveness in preventing trauma-related psychopathology is lacking.
This paper presents a monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) design suitable for radio astronomy applications based on a commercially available 100 nm gate length ...gallium arsenide pseudomorphic high electron mobility transistor process. The MMIC exhibits a simulated noise figure of less than 1.2 dB at room temperature between 13.6 - 24 GHz. When measured on-wafer, the forward transmission is greater than 22 dB across the operational bandwidth, with input and output return losses less than -5.5 and -16 dB, respectively. The total power dissipation is 41 mW. Comparing these results with those of state-of-the-art LNAs in the literature shows that this process should be capable of achieving performance comparable to more specialized technology, allowing radio astronomy to take advantage of the benefits of commercial technology.
We present narrow and broad K-band observations of the Class 0/I source IRAS 18148-0440 that span 17 years. The infrared nebula associated with this protostar in the L483 dark cloud is both ...morphologically and photometrically variable on a timescale of only a few months. This nebula appears to be an infrared analog to other well known optically visible variable nebulae associated with young stars, such as Hubble's Variable Nebula. Along with Cepheus A, this is one of the first large variable nebulae to be found that is only visible in the infrared. The variability of this nebula is most likely due to changing illumination of the cloud rather than any motion of the structure in the nebula. Both morphological and photometric changes are observed on a timescale only a few times longer than the light crossing time of the nebula, suggesting very rapid intrinsic changes in the illumination of the nebula. Our narrowband observations also found that H{sub 2} knots are found nearly twice as far to the east of the source as to its west, and that H{sub 2} emission extends farther east of the source than the previously known CO outflow.
Potential for Ethnic Conflict in China Fuller, Gary A.; Morrison, Rebecca; Murphy, Alexander B. ...
Eurasian geography and economics,
12/2002, Volume:
43, Issue:
8
Journal Article
Peer reviewed
This paper, part of a broader effort to construct an analytical approach that can be used to assess near-term ethnic conflict potential in different parts of the world, examines the possibility of ...such conflict in China. More specifically, the authors employ a theory of measurement based on subjective judgment and pairwise comparison to quantify the factors likely to produce interethnic strife, encompassing the notion that, in most cases, ethnic conflict is driven by competition over territory. Five potential ethnic fracture zones are identified, described, and mapped. Journal of Economic Literature, Classification Numbers: I31, J15, Z00. 6 figures, 1 appendix (4 tables), 51 references.
HEMT-based Low Noise Amplifiers (LNAs) are often used as the primary sensing device in microwave/millimeter-wave receiver systems. In noise critical applications, such as radio astronomy, to improve ...their noise performance, they are cooled to cryogenic temperatures of 20 K and lower. At room temperature, the small signal equivalent circuit (SSEC) of HEMT transistors is well-known and supports LNA design. At low temperatures, however, the circuit model is less representative due to temperature related effects that alter the device current-voltage response. In order to improve the understanding of cryogenic HEMT performance, the SSEC parameters of a commercial 100nm gate length GaAs pHEMT have been extracted across a range of temperatures extending from 4 K to 293 K. The results indicate an unexpectedly complex temperature dependent behavior with variation in the SSEC parameters occurring as the transistor is cooled below 150 K and 15 K. The experimental data and extracted SSEC parameters will support future LNA designs across a range of low temperature operating conditions and help to guide the selection of parameters such as the optimum temperature for operation. In addition, the SSEC can also provide key insights into the operation of HEMT transistors at low temperatures.
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 85.69 and 99.02 GHz continuum emission and H42\(\alpha\) and H40\(\alpha\) lines emission from the central 1~kpc of NGC ...1808. These forms of emission are tracers of photoionizing stars but unaffected by dust obscuration that we use to test the applicability of other commonly star formation metrics. An analysis of the spectral energy distributions shows that free-free emission contributes about 60 to 90 per cent of the continuum emission in the 85-100 GHz frequency range, dependent on the region. The star formation rate (SFR) derived from the ALMA free-free emission is \(3.1\pm0.3\)~M\(_\odot\)~yr\(^{-1}\). This is comparable to the SFRs measured from the infrared emission, mainly because most of the bolometric energy from the heavily obscured region is emitted as infrared emission. The radio 1.5~GHz emission yields a SFR 25 per cent lower than the ALMA value, probably because of the diffusion of the electrons producing the synchrotron emission beyond the star-forming regions. The SFRs measured from the extinction-corrected H\(\alpha\) line emission are about 40 to 65 per cent of the SFR derived from the ALMA data, likely because this metric was not calibrated for high extinction regions. Some SFRs based on extinction-corrected ultraviolet emission are similar to those from ALMA and infrared data, but given that the ultraviolet terms in the extinction correction equations are very small, these metrics seem inappropriate to apply to this dusty starburst.
The formation of stellar clusters dictates the pace at which galaxies evolve, and solving the question of their formation will undoubtedly lead to a better understanding of the Universe as a whole. ...While it is well known that star clusters form within parsec-scale over-densities of interstellar molecular gas called clumps, it is, however, unclear whether these clumps represent the high-density tip of a continuous gaseous flow that gradually leads towards the formation of stars, or a transition within the gas physical properties. Here, we present a unique analysis of a sample of 27 infrared dark clouds embedded within 24 individual molecular clouds that combine a large set of observations, allowing us to compute the mass and velocity dispersion profiles of each, from the scale of tens of parsecs down to the scale of tenths of a parsec. These profiles reveal that the vast majority of the clouds, if not all, are consistent with being self-gravitating on all scales, and that the clumps, on parsec-scale, are often dynamically decoupled from their surrounding molecular clouds, exhibiting steeper density profiles (\(\rho\propto r^{-2}\)) and flat velocity dispersion profiles (\(\sigma\propto r^0\)), clearly departing from Larson's relations. These findings suggest that the formation of star clusters correspond to a transition regime within the properties of the self-gravitating molecular gas. We propose that this transition regime is one that corresponds to the gravitational collapse of parsec-scale clumps within otherwise stable molecular clouds.
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