On faint companions in the close environment of star-forming dwarf galaxies. Possible external star formation triggers ?

We have searched for companion galaxies in the close environment of 98 star-forming dwarf galaxies (SFDGs) from field and low density environments, using the NASA Extragalactic Database. Most of the companions are dwarf galaxies which due to observational selection effects were previously disregarded in environmental studies of SFDGs. A subsample at low redshift, cz<2000 km/s, was chosen to partially eliminate the observational bias against distant dwarf companions. We find companion candidates for approximately 30% of the objects within a projected linear separation s_p<100 kpc and a redshift difference (Delta cz)<500 km/s. The limited completeness of the available data sets, together with the non-negligible frequency of HI clouds in the vicinity of SFDGs indicated by recent radio surveys, suggest that a considerably larger fraction of these galaxies may be accompanied by low-mass systems. This casts doubt on the hypothesis that the majority of them can be considered truly isolated. The velocity differences between companion candidates and sample SFDGs amount typically to (Delta cz)<250 km/s, and show a rising distribution towards lower (Delta cz). This is similarly found for dwarf satellites of spiral galaxies, suggesting a physical association between the companion candidates and the sample SFDGs. SFDGs with a close companion do not show significant differences in their Hbeta equivalent widths and B-V colours as compared to isolated ones. However, the available data do not allow us to rule out that interactions with close dwarf companions can influence the star formation activity in SFDGs.Comment: 9 pages, 5 figures, to appear in A&A; also available at http://www.uni-sw.gwdg.de/~knoeske/PUB_LIST/sfdg_comps.ps.g

Violence, uncertainty, and resilience among refugee women and community workers: An evaluation of gender-based violence case management services in the Dadaab refugee camps.

Reports of gender-based violence (GBV) are common in camps for refugees and displaced populations. In the Dadaab refugee camps in north-eastern Kenya, the International Rescue Committee (IRC) and CARE International (CARE) implement programmes that aim to both respond to and prevent GBV. A cornerstone of this work has been to train refugees, known as refugee community workers, to deliver aspects of GBV prevention and response work in order to develop a broader implementation of traditional GBV outreach, community mobilisation, and case management. To date, there has been limited rigorous research on this broader GBV case management plus task sharing approach in the context of a refugee camp setting. To address this key gap in evidence, the London School of Hygiene and Tropical Medicine (LSHTM) and the African Population and Health Research Centre (APHRC), in collaboration with IRC and CARE, have sought to assess this model to understand its feasibility, acceptability, and influence among female survivors of GBV accessing care. Data for this study, funded by UK aid, were collected in the Dadaab refugee camps between 2014 and 2017, which coincided with a temporary decision to close the camp and repatriate Somali refugees. The research confirms the magnitude and complexity of the violence that women and girls experience in the camps in Dadaab. In the year leading up to this study, 47% of women accessing the GBV centres for case management reported experiencing intimate partner violence and 39% reported experiencing non-partner violence. In addition, the study highlights the specific risks, challenges, opportunities and rewards experienced by refugee community workers in their dual role of community members and GBV activists living side-by-side with survivors and perpetrators of violence. Solely related to their work as GBV caseworkers, one in three refugee community workers reported experiencing non-partner violence in the last 12 months. Despite this, 93% of refugee community workers stated their work was rewarding or extremely rewarding. The majority of women (82%) accessing services reported that their interactions with refugee community workers had a positive effect, and that working with them was useful. However, having refugees deliver services to their own community was not without its challenges, and survivors raised issues on confidentiality, mistranslations, and perceived biases on clan differences. The study also provides an insight into the importance of contextual factors in case management, and the impact of the announcement of the (now-delayed) camp closure in Dadaab. Priorities of both the camp population and service providers (GBV and referral services) shifted greatly during this time of uncertainty and affected when and how women were accessing services

Gender-based violence and its association with mental health among Somali women in a Kenyan refugee camp: a latent class analysis

BACKGROUND: In conflict-affected settings, women and girls are vulnerable to gender-based violence (GBV). GBV is associated with poor long-term mental health such as anxiety, depression and post-traumatic stress disorder (PTSD). Understanding the interaction between current violence and past conflict-related violence with ongoing mental health is essential for improving mental health service provision in refugee camps. METHODS: Using data collected from 209 women attending GBV case management centres in the Dadaab refugee camps, Kenya, we grouped women by recent experience of GBV using latent class analysis and modelled the relationship between the groups and symptomatic scores for anxiety, depression and PTSD using linear regression. RESULTS: Women with past-year experience of intimate partner violence alone may have a higher risk of depression than women with past-year experience of non-partner violence alone (Coef. 1.68, 95% CI 0.25 to 3.11). Conflict-related violence was an important risk factor for poor mental health among women who accessed GBV services, despite time since occurrence (average time in camp was 11.5 years) and even for those with a past-year experience of GBV (Anxiety: 3.48, 1.85-5.10; Depression: 2.26, 0.51-4.02; PTSD: 6.83, 4.21-9.44). CONCLUSION: Refugee women who experienced past-year intimate partner violence or conflict-related violence may be at increased risk of depression, anxiety or PTSD. Service providers should be aware that compared to the general refugee population, women who have experienced violence may require additional psychological support and recognise the enduring impact of violence that occurred before, during and after periods of conflict and tailor outreach and treatment services accordingly

The even darker side of the eastern gray squirrel (Sciurus carolinensis): a review of global introductions, invasion biology, and pest management strategies

Huynh, H.M., Bertolino, S., Lurz, P.W.W., Koprowski, J.L., Williams, G.R., Thompson, C.W., McAlpine, D.F

Evolution of faint radio sources in the VIDEO-XMM3 field

© 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical SocietyIt has been speculated that low-luminosity radio-loud active galactic nuclei (AGN) have the potential to serve as an important source of AGN feedback, and may be responsible for suppressing star formation activity in massive elliptical galaxies at late times. As such the cosmic evolution of these sources is vitally important to understand the significance of such AGN feedback processes and their influence on the global star formation history of the Universe. In this paper, we present a new investigation of the evolution of faint radio sources out to z ~ 2.5. We combine a 1 square degree Very Large Array radio survey, complete to a depth of 100 μJy, with accurate 10 band photometric redshifts from the following surveys: Visible and Infrared Survey Telescope for Astronomy Deep Extragalactic Observations and Canada-France-Hawaii Telescope Legacy Survey. The results indicate that the radio population experiences mild positive evolution out to z ~ 1.2 increasing their space density by a factor of ~3, consistent with results of several previous studies. Beyond z = 1.2, there is evidence of a slowing down of this evolution. Star-forming galaxies drive the more rapid evolution at low redshifts, z 1.2. The evolution is best fitted by pure luminosity evolution with star-forming galaxies evolving as (1 + z)2.47 ± 0.12 and AGN as (1 + z)1.18 ± 0.21M.Peer reviewe

Differences in IDO1+ dendritic cells and soluble CTLA-4 are associated with differential clinical responses to methotrexate treatment in rheumatoid arthritis

ObjectiveAntigen-presenting dendritic cells (DCs) and monocytes play an essential role in rheumatoid arthritis (RA) pathogenesis, however, their tolerogenic potential remains unclear. Herein, the tolerogenic profiles of DCs are characterized in treatment-naïve RA patients to determine their role to inflammatory arthritis management.MethodsThirty-six treatment-naïve RA patients were enrolled, of which 62% were non-responders to methotrexate (MTX) monotherapy based on disease activity score (DAS) after 6-months of therapy. DC and monocyte subset frequencies, activation (CD40, CD86, CD209 expression), and tolerogenic profile (intracellular indoleamine-2,3-dioxygenase [IDO1] and cytotoxic T lymphocyte antigen 4 [CTLA-4] expression) were examined in the baseline peripheral blood by multicolor flow-cytometry. Soluble CTLA-4 (sCTLA-4) levels in plasma were measured.ResultsDC subsets were decreased in RA compared to healthy controls (HC), and the frequency of conventional DCs (cDC) inversely correlated with inflammatory markers and improvement in disease activity. CD141+ cDC1s were the major IDO1-expressing cells. IDO1+cDC1s were reduced in RA patients compared to HC. The baseline frequency of IDO1+cDC1s inversely correlated with improvement in disease activity. CTLA-4 expression in CD1c+ cDC2s and monocytes was lower in RA patients compared to HC. Moreover, MTX-responders had a significantly lower frequency of IDO1+cDC1 cells and higher level of sCTLA-4 in the plasma compared to MTX non-responders. There was a strong predictive association of low IDO1+cDC1 cells, low sCTLA-4 and non-response to MTX.ConclusionsOur findings reveal altered DC and monocytes immunophenotypes that are associated with RA pathology and treatment response. The frequencies of tolerogenic IDO1+cDC1s and the low level of sCTLA-4 are strongly associated with MTX non-responsiveness and therapeutic outcome. These results suggest that investigation of the association IDO1+cDC1 and sCTLA-4 with response to treatment may be more generalizable to other autoimmune diseases

Joule-assisted silicidation for short-channel silicon nanowire devices

We report on a technique enabling electrical control of the contact silicidation process in silicon nanowire devices. Undoped silicon nanowires were contacted by pairs of nickel electrodes and each contact was selectively silicided by means of the Joule effect. By a realtime monitoring of the nanowire electrical resistance during the contact silicidation process we were able to fabricate nickel-silicide/silicon/nickel- silicide devices with controlled silicon channel length down to 8 nm.Comment: 6 pages, 4 figure

Towards the fabrication of phosphorus qubits for a silicon quantum computer

The quest to build a quantum computer has been inspired by the recognition of the formidable computational power such a device could offer. In particular silicon-based proposals, using the nuclear or electron spin of dopants as qubits, are attractive due to the long spin relaxation times involved, their scalability, and the ease of integration with existing silicon technology. Fabrication of such devices however requires atomic scale manipulation - an immense technological challenge. We demonstrate that it is possible to fabricate an atomically-precise linear array of single phosphorus bearing molecules on a silicon surface with the required dimensions for the fabrication of a silicon-based quantum computer. We also discuss strategies for the encapsulation of these phosphorus atoms by subsequent silicon crystal growth.Comment: To Appear in Phys. Rev. B Rapid Comm. 5 pages, 5 color figure

HER2 overexpression and amplification is present in a subset of ovarian mucinous carcinomas and can be targeted with trastuzumab therapy

<p>Abstract</p> <p>Background</p> <p>The response rate of ovarian mucinous carcinomas to paclitaxel/carboplatin is low, prompting interest in targeted molecular therapies. We investigated HER2 expression and amplification, and the potential for trastuzumab therapy in this histologic subtype of ovarian cancer.</p> <p>Methods</p> <p>HER2 status was tested in 33 mucinous carcinomas and 16 mucinous borderline ovarian tumors (BOT)). Five cases with documented recurrence and with tissue from the recurrence available for testing were analyzed to determine whether HER2 amplification status changed over time. Three prospectively identified recurrent mucinous ovarian carcinomas were assessed for HER2 amplification and patients received trastuzumab therapy with conventional chemotherapy.</p> <p>Results</p> <p>Amplification of HER2 was observed in 6/33 (18.2%) mucinous carcinomas and 3/16 (18.8%) BOT. HER2 amplification in primary mucinous carcinomas was not associated with an increased likelihood of recurrence. The prospectively identified recurrent mucinous carcinomas showed overexpression and amplification of HER2; one patient's tumor responded dramatically to trastuzumab in combination with conventional chemotherapy, while another patient experienced an isolated central nervous system recurrence after trastuzumab therapy.</p> <p>Conclusion</p> <p>HER2 amplification is relatively common in ovarian mucinous carcinomas (6/33, 18.2%), although not of prognostic significance. Trastuzumab therapy is a treatment option for patients with mucinous carcinoma when the tumor has HER2 amplification and overexpression.</p