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To experience sexual violence and abuse is to experience silence. This commentary explores some of the ways in which psychiatry reinforces the silencing of sexual violence survivors. We argue that current psychiatric responses to sexual violence typically constitute iatrogenic harm including through: a failure to provide services that meet survivors’ needs, a failure to believe or validate disclosures; experiences of medicalisation and diagnoses which can delegitimise people's own knowledge and meaning; ‘power over’ relational approaches which can prevent compassionate responses and result in staff having to develop their own coping strategies; and poorly addressed and reported experiences of sexual violence within psychiatric settings. We argue that these multiple forms of silencing have arisen in part because of biomedical dominance, a lack of support and training in sexual violence for staff, inconsistent access to structured, reflective supervision, and the difficulties of facing the horror of sexual violence and abuse. We then describe community-based and grassroots responses, and consider the potential of trauma-informed approaches. Whilst this paper has a UK focus, some aspects will resonate globally, particularly given that Western psychiatry is increasingly being exported around the globe.
European dry-wood termites belong to the genus Kalotermes (Kalotermitidae), one of the two termite genera in Europe. Until the recent description of two new species, Kalotermes italicus in Italy and Kalotermes phoenicae in the eastern Mediterranean area, Kalotermes flavicollis was the only taxon known in this region. The presence of additional entities, suggested by morphological and physiological variation observed in K. flavicollis, was supported by molecular studies revealing four distinct genetic lineages: lineage A, K. flavicollis sensu strictu, from the Aegean area to Italy; lineage B, in Tuscany; lineage SC, in Sardinia and Corsica; lineage SF, in southern France. Lineages A and B may form mixed colonies, suggesting hybridization. To draw a more detailed picture of Kalotermes evolution and biogeography in Europe, we analyzed samples from previously unsampled areas, such as Spain and southern Italy, by means of the highly informative cox1/trnL/cox2 mitochondrial DNA marker. Overall, phylogenetic analyses confirmed previously identified lineages and taxa, but widened the distribution of the lineage SC to the mainland and of the lineage SF to Spain and Portugal. Results further provided evidence for the synonymy between lineage B and K. italicus. Species delimitation analysis suggested that the three K. flavicollis lineages, as well as K. italicus, can be separate taxa. Data also suggest a possible interspecific hybridization between K. italicus and both K. flavicollis lineages A and SC.
A series of clinopyroxenes along the CaMgSi2O6–CaCoSi2O6 join was synthesized by quenching from melts at 1500°C and subsequent annealing at 1250°C (at 0.0001 GPa). This protocol proved to be the most effective to obtain homogenous, impurity-free and stoichiometric pyroxenes. Electron microprobe analyses in energy dispersive mode were conducted and single-crystal X-ray diffraction data were collected on Ca (CoxMg1-x)Si2O6 pyroxenes with x = 0.2, 0.4, 0.5, 0.6. Effects of cation substitution at the M1 site are described. The experimental findings of this study allow us to extend the comparative analysis of the structural features of pyroxenes with divalent cations at the M1 and M2 sites.
High resolution maps of the Galactic radio source CTB80 at three different frequencies are presented. A new interpretation in terms of a cosmic collision between two SNRs of different age is suggested.
CTB80 is one of the most mystifying Galactic Objects yet discovered and has recently attracted considerable attention from X-ray, optical and radio astronomers (see for example: Becker et al. (1981), Angerhofer et al. (1980, 1981), Velusamy et al. (1976), van den Bergh (1980).
The present observations of the radio continuum emission of the extended feature at 408 MHz, 1720 MHz and 4750 MHz and the linearly polarized emission at 1720 MHz and 4750 MHz (Figs 1,2,3) throw new light on the morphological, spectral and polarization properties of the whole source.
Results obtained on the Low Frequency Variability (LFV) phenomenon, by means of combined multifrequency observations of 50 sources, on a period of more than ten years on a frequency grid of 0.4, 2.3, 4.8, 8.0, and 14.4 GHz and two epoch VLBI observations at 18 cm can be summarized as follows:
1.15–20% of variables appear to have variations consisting either of quasi-simultaneous outbursts at all frequencies or of bursts which drift to lower frequencies with time and decreasing amplitude. In our sample, we find five good cases: 3C 120, 0605-085, 1510-089, 3C 345, BL Lac. Three of these are famous superluminals; the other two show significant structural changes between our 18 cm VLBI measurements. The corresponding expansion rate for these five sources is in agreement with the γ's derived from LFV with the usual causality arguments. For the sources of this class, the observations are therefore in agreement with models that explain the phenomenon of the variability as synchrotron emission of relativistic electrons beamed in a direction close to the line of sight.
2.35% of variables show only low frequency (<1 GHz) variability and little or no intermediate high frequency variations. In DA 406, prototype of the category, no superluminal motions have been observed, even if the resolution of our VLBI observations should allow the detection of the structural change expected on the basis of intrinsic LFV. In this case we do not find direct evidence of relativistic motions associated with the LFV and the process is most easily explained if the variations are extrinsic (propagation effects through the interstellar medium as the slow refractive scintillation).
3.The remaining 40–45% of variables show uncorrelated high (<5 GHz) and low frequency variability with a minimum of activity at the intermediate frequencies. The explanation of the phenomenon is less clear. It could be attributed to intrinsic (superluminal) variations at high frequencies, coexisting with unrelated processes at low frequencies.
The apparent spot sizes of OH masers appear to be significantly broadened when seen through the inner galaxy or large extents of the galactic disk (Burke 1968). Bowers et al (1980) found evidence of small-scale structure (≲ 50 mas) in OH sources at distances of less than 5 kpc but this was characteristically absent in very distant sources (≳ 8kpc) at galactic longitudes 1 ≲ 40°. This result is typically explained in terms of interstellar scattering (ISS) by intervening diffuse HII regions.
At the beginning of 1980 the Istituto di Radioastronomia of the Consiglio Nazionale delle Ricerche (C.N.R.) started the Italian VLBI Project.
The first antenna was completed in October 1983 (see Table 1 for telescope characteristics). The first VLBI Mark2 experiment was performed in March 1984. In December 1984 we had the first Mark3 experiment. From that time our Institute is officially member of the European VLBI Network (EVN) and since January 1986 it is also Associate Member of the US Network.
The high resolution obtained through the use of VLBI gives an unique opportunity to directly observe the interaction of an expanding radio supernova with its surrounding medium. We present here results from our VLBI observations of the young supernovae SN 1979C, SN 1986J, and SN 2001gd.
The flux variability of extragalactic radio sources at decimetric wavelengths (Low Frequency Variability LFV) is mostly associated with the nuclei of compact radio sources. But is a not yet well understood phenomenon. The main question still is: where does this phenomenon take place?
Snapshot VLBI observations at 18 cm have been obtained with a global array at three epochs (1980.1, 1981.8, 1987.9) in order to investigate flux density and/or structural variations for a sample of 21 low frequency variable sources (Padrielli et al. 1987 Astron Astrophys. Suppl. Ser., 67, 63; Bondi et al. 1993 in preparation).
There is some evidence from earlier studies that the two sources 0235 — 197 and 1203 + 043 exhibit low frequency (< 1 GHz) variability. This work shows that both sources have linear polarizations, if any, below the detection limits at 320 MHz, so we cannot explain the variability as being due to instrumental polarization effects as has been suggested for 3C159. Refractive scintillation may be the cause of the variability in 0235—197. The radio source 1203+043 lacks any bright compact component thereby ruling out a refractive scintillation mechanism for its variability. Consequently, it is possible that claims of variability in this source are spurious. However, the 320 MHz VLA observations show that 1203+043 has an ‘X'-shaped radio structure.
An international Low Frequency VLBI Network (LFVN) has been organized for observations at 327 MHz and 1665 MHz frequencies with MARK-II and S2 recording terminals. Data on the interplanetary medium and spike-like solar bursts were obtained in first preliminary experiments.
A majority of compact steep-spectrum (CSS) and GHz-peaked spectrum (GPS) sources show low integrated polarizations (≲ 1%) at or below 5 GHz. To investigate whether this is mostly due to large rotation measures (RMs) arising from their being cocooned in dense gaseous envelopes we have observed 26 CSSs and GPSs at 8 and 15 GHz with the VLA A-array. The sample includes equal numbers whose hosts are galaxies and quasars.
Compact Steep-Spectrum (CSS) and GHz-Peaked Spectrum (GPS) radio sources are intrinsically small objects (Fanti et al. 1990) with high frequency steep spectra (α > 0.5 with S∝ v–α), found at moderate or high redshifts (z>0.2 but many objects have z>1.5). Their characteristics have been interpreted in terms of youth (e.g. Fanti et al. 1995) or “frustration” (e.g. van Breugel et al. 1984). Their radio spectra turn over at tens or a few hundreds of MHz (CSS) or at higher frequencies (GPS), interpreted as due to synchrotron self-absorption. They represent a significant fraction of flux limited catalogues (15–30 %, depending on the frequency).
Recently we focussed our attention on a sample of Compact Steep-spectrum Sources (CSSs) selected because of the large bent radio jets seen in the inner region of emission. The largest distortions are often seen in sources dominated by jets, and there are suggestions that this might to some extent be due to projection effects. However, superluminal motion is rare in CSSs. The only case we know of so far is 3C147 (Alef at al. 1990) with a mildly superluminal speed of ≃ 1.3v/c. Moreover, the core fractional luminosity in CSSs is ≃ 3% and ≤ 0.4% for quasars and radio galaxies respectively. Similar values are found for large size radio sources i.e. both boosting and orientations in the sky are similar for the two classes of objects. An alternative possibility is that these bent-jet sources might also be brightened by interactions with the ambient media. There are clear indications that intrinsic distortions due to interactions with a dense inhomogeneous gaseous environment play an important role. Observational support comes from the large RMs found in CSSs (Taylor et al. 1992; Mantovani et al. 1994; Junor et al. these proc.) and often associated with strong depolarization (Garrington & Akujor, t.p.). The CSSs also have very luminous Narrow Line Regions emission, with exceptional velocity structure (Gelderman, t.p.).
We performed a multifrequency and multiepoch study of the quasar PKS 1510-089 with ground and space VLBI, in order to study its nuclear properties and test current models for the production of the emission at X- and γ-ray energies. A preliminary analysis of our images suggests that the lower limit to the Lorentz factor γ at the distance of ∼ 12 pc from the central engine is γmin = 5. We used Ho = 100 km s−1 Mpc−1.
Two Compact Steep-spectrum Sources (CSSs), 0548+165 and 1524-136, have been observed in dual polarization with the VLBA at 4.9 and 8.4 GHz. Rotation measures (RMs) up to 104 rad m−2 were derived for the jets of both sources. These high values possibly arise due to the external medium interacting with the radio jets, with measured depolarization being due to small-scale inhomogeneities in the medium.
A few compact steep-spectrum sources (CSSs) have been observed with the VLBA at 8.4 GHz and MERLIN at 5 GHz to study the possible dynamical interaction between jets and the ambient media suggested by previous measurements of the rotation measures.
The results of VLBI observations of the quasar 3C 273, obtained during a multi-frequency campaign in late 1992 in the radio, millimeter, and X-ray bands are presented. The aim of the campaign was to test the application of the SSC (Synchrotron Self-Compton) model to 3C 273. Independent estimates are obtained through the assumption of the energy equipartition between particles and magnetic field.
With new 6 cm observations we confirm the self-similar expansion of SN 1993J previously discovered at 3.6 cm and estimate the expansion deceleration parameter. The results are inconsistent with the existence of a constant pre-explosion stellar wind but otherwise confirm the standard radio supernova model. The first map at 13 cm showing shell structure is also presented.