667 research outputs found
Treatment and outcomes for synovial sarcoma patients in Western Australia: the role of neoadjuvant chemoradiotherapy
Background
This is a retrospective review of synovial sarcoma (SS) patients treated over the last 12âyears in Western Australia (WA). SS is both chemo and radiotherapy sensitive. Results of trials in adjuvant chemotherapy are conflicting and there is limited support for neoadjuvant chemotherapy. The use of combined chemoradiotherapy is based on institutional preferences.
Aim
We reviewed the outcomes for SS patients treated in WA over a 12âyear period focusing on patients who received neoadjuvant chemoradiotherapy (NACRT).
Methods
Patient details including demographics, histopathology, treatment details, were obtained from the WA sarcoma database (2006-2018). Progression free survival (PFS) and overall survival (OS) were derived for whole cohort.
Results
Twenty seven patients were identified with SS with equal gender incidence. Median age of the cohort was 36 (14-76) years. The most common primary site of disease was extremity (81.5%). 22/27 patients presented with only localized disease and 59.2% of these received neo-adjuvant treatment. Of those who received neoadjuvant treatment, 56.2% had NACRT, while 25.0% and 18.7% of patients had chemotherapy and radiotherapy respectively. Mesna, doxorubicin, ifosfamide, dacarbazine (MAID) was the most commonly used chemotherapy regimen as neoadjuvant or adjuvant treatment while ifosfamide (93.7%) was the most commonly used chemotherapy drug in any setting. There was no reported case of disease progression in group of patients who received NACRT apart from one patient who had oligometastatic disease at diagnosis. Median OS of the whole cohort was 38âmonths while median PFS was 24âmonths. Bone marrow toxicity was the most commonly reported high grade toxicity in NACRT group (55.5%) but there were no treatment related deaths.
Conclusion
NACRT is not widely adopted and treatment is based on institutional preferences, however our data shows that NACRT is a feasible therapy option. NACRT should be evaluated prospectively in a randomized trial
Ammonia in Infrared Dark Clouds
Infrared Dark Clouds appear to be the long sought population of cold and
dense aggregations with the potential of harbouring the earliest stages of
massive star formation. Up to now there has been no systematic study on the
temperature distribution, velocity fields, chemical and physical state toward
this new cloud population. Knowing these properties is crucial for
understanding the presence, absence and the very potential of star formation.
The present paper aims at addressing these questions. We analyse temperature
structures and velocity fields and gain information on their chemical
evolution. The gas emission is remarkably coextensive with the extinction seen
at infrared wavelengths and with the submillimeter dust emission. Our results
show that IRDCs are on average cold (T < 20 K) and have variations among the
different cores. IRDC cores are in virial equilibrium, are massive (M > 100
M_sun), highly turbulent (1 -- 3 km/s) and exhibit significant velocity
structure (variations around 1 -- 2 km/s over the cloud). We find an increasing
trend in temperature from IRDCs with high ammonia column density to high mass
protostellar objects and hot core/Ultracompact Hii regions stages of early warm
high-mass star formation while linewidths of IRDCs are smaller. On the basis of
this sample, we infer that while active star formation is not yet pervasive in
most IRDCs, local condensations might collapse in the future or have already
begun forming stars.Comment: 17 pages, 11 figures, in press in Astronomy & Astrophysic
Perspective: Advancing the research agenda for improving understanding of cyanobacteria in a future of global change
Harmful cyanobacterial blooms (=cyanoHABs) are an increasing feature of many waterbodies throughout the world. Many bloom-forming species produce toxins, making them of particular concern for drinking water supplies, recreation and fisheries in waterbodies along the freshwater to marine continuum. Global changes resulting from human impacts, such as climate change, over-enrichment and hydrological alterations of waterways, are major drivers of cyanoHAB proliferation and persistence. This review advocates that to better predict and manage cyanoHABs in a changing world, researchers need to leverage studies undertaken to date, but adopt a more complex and definitive suite of experiments, observations, and models which can effectively capture the temporal scales of processes driven by eutrophication and a changing climate. Better integration of laboratory culture and field experiments, as well as whole system and multiple-system studies are needed to improve confidence in models predicting impacts of climate change and anthropogenic over-enrichment and hydrological modifications. Recent studies examining adaptation of species and strains to long-term perturbations, e.g. temperature and carbon dioxide (CO2) levels, as well as incorporating multi-species and multi-stressor approaches emphasize the limitations of approaches focused on single stressors and individual species. There are also emerging species of concern, such as toxic benthic cyanobacteria, for which the effects of global change are less well understood, and require more detailed study. This review provides approaches and examples of studies tackling the challenging issue of understanding how global changes will affect cyanoHABs, and identifies critical information needs for effective prediction and management
Accommodating 'others'?: housing dispersed, forced migrants in the UK
Utilising insights from a qualitative study in the city of Leeds (UK), this paper considers issues related to the housing of dispersed forced migrants. The term 'dispersed forced migrants' is used here as a general label to include four groups of international migrants (i.e. refugees, asylum seekers, those with humanitarian protection status and failed asylum seekers) who have previously been dispersed, on a no choice basis, to a variety of locations across the UK under the requirements of the Immigration and Asylum Act (1999). The tiering of housing entitlement that exists within the generic population of dispersed forced migrants (a consequence of the particular socio-legal status assigned to individuals), and its role in rendering migrants susceptible to homelessness is outlined. The adequacy/standard of accommodation made available to forced migrants is also discussed. It is concluded that current arrangements fail to meet the basic housing needs of many forced migrants. Any future improvement in this situation will require a significant shift in government policy
Initial phases of massive star formation in high infrared extinction clouds. I. Physical parameters
The earliest phases of massive star formation are found in cold and dense
infrared dark clouds (IRDCs). Since the detection method of IRDCs is very
sensitive to the local properties of the background emission, we present here
an alternative method to search for high column density in the Galactic plane
by using infrared extinction maps. We find clouds between 1 and 5 kpc, of which
many were missed by previous surveys. By studying the physical conditions of a
subsample of these clouds, we aim at a better understanding of the initial
conditions of massive star formation. We made extinction maps of the Galactic
plane based on the 3.6-4.5 microns color excess between the two shortest
wavelength Spitzer IRAC bands, reaching to visual extinctions of ~100 mag and
column densities of 9x10^22 cm^-2. From this we compiled a new sample of cold
and compact high extinction clouds. We used the MAMBO array at the IRAM 30m
telescope to study the morphology, masses and densities of the clouds and the
dense clumps within them. The latter were followed up by pointed ammonia
observations with the 100m Effelsberg telescope, to determine rotational
temperatures and kinematic distances. Extinction maps of the Galactic plane
trace large scale structures such as the spiral arms. The 1.2 mm emission maps
reveal that the high extinction clouds contain extended cold dust emission,
from filamentary structures to still diffuse clouds. Most of the clouds are
dark in 24 microns, but several show already signs of star formation via maser
emission or bright infrared sources, suggesting that the high extinction clouds
contain a variety of evolutionary stages. The observations suggest an
evolutionary scheme from dark, cold and diffuse clouds, to clouds with a
stronger 1.2 mm peak and to finally clouds with many strong 1.2 mm peaks, which
are also warmer, more turbulent and already have some star formation signposts.Comment: 26 pages, 14 figures, 9 tables. Accepted for publication in Astronomy
and Astrophysics, small corrections implemente
The IRAC point response function in the warm Spitzer mission
The Infrared Array Camera (IRAC) is now the only science instrument in operation on the Spitzer Space Telescope. The 3.6 and 4.5 Âľm channels are temperature-stabilized at ~28.7K, and the sensitivity of IRAC is nearly identical to what it was in the cryogenic mission. The instrument point response function (PRF) is a set of values from which one can determine the point spread function (PSF) for a source at any position in the field, and is dependent on the optical characteristics of the telescope and instrument as well as the detector sampling and pixel response. These data are necessary when performing PSF-fitting photometry of sources, for deconvolving an IRAC image, subtracting out a bright source in a field, or for estimating the flux of a source that saturates the detector. Since the telescope and instrument are operating at a higher temperature in the post-cryogenic mission, we re-derive the PRFs for IRAC from measurements obtained after the warm mission temperature set point and detector biases were finalized and compare them to the 3.6 and 4.5 Âľm PRFs determined during the cryogenic mission to assess any changes
LABOCA mapping of the infrared dark cloud MSXDC G304.74+01.32
Infrared dark clouds (IRDCs) likely represent very early stages of high-mass
star/star cluster formation. In this study, we aim to determine the physical
properties and spatial distribution of dense clumps in the IRDC MSXDC
G304.74+01.32 (G304.74), and bring these characteristics into relation to
theories concerning the origin of IRDCs and their fragmentation into clumps and
star-forming cores. G304.74 was mapped in the 870 m dust continuum with
the LABOCA bolometer on APEX. Archival MSX and IRAS infrared data were used to
study the nature and properties of the submillimetre clumps within the cloud.
There are 8 clumps within G304.74 which are not associated with mid-infrared
(MIR) emission. Some of them are candidates for being/harbouring high-mass
starless cores (HMSCs). We compared the clump masses and their spatial
distribution in G304.74 with those in several other recently studied IRDCs.
There is a high likelihood that the clump mass distributions in G304.74 and in
several other IRDCs represent the samples of the same parent distribution. In
most cases the spatial distributions of clumps in IRDCs do not deviate
significantly from random distributions. This is consistent with the idea that
the origin of IRDCs, and their further sub-fragmentation down to scales of
clumps is caused by supersonic turbulence in accordance with results from giant
molecular clouds.Comment: 15 pages, 8 figures, accepted for publication in Astronomy and
Astrophysic
The influence of binarity on dust obscuration events in the planetary nebula M 2-29 and its analogues
The central star of the planetary nebula (CSPN) M 2-29 shows an extraordinary
R Coronae Borealis-like fading event in its optical lightcurve. The only other
CSPN to show these events are CPD-568032 (Hen 3-1333) and V651 Mon (NGC 2346).
Dust cloud formation in the line of sight appears responsible but the exact
triggering mechanism is not well understood. Understanding how planetary
nebulae (PNe) trigger dust obscuration events may help understand the same
process in a wide range of objects including Population-I WC9 stars, symbiotic
stars and perhaps Asymptotic Giant Branch (AGB) stars with long secondary
periods (LSPs). A binary scenario involving an eccentric, wide companion that
triggers dust formation via interaction at periastron is a potential
explanation that has been suggested for LSP variables. Model fits to the
lightcurves of CPD-568032 and M 2-29 show the dust forms in excess of 70 AU at
the inner edge of a dust disk. In the case of CPD-568032 this radius is far too
large to coincide with a binary companion trigger, although a binary may have
been responsible for the formation of the dust disk. We find no direct evidence
to support previous claims of binarity in M 2-29 either from the OGLE
lightcurve or deep medium-resolution VLT FLAMES spectroscopy of the CSPN. We
classify the CSPN as Of(H) with T_eff=50+-10 kK and log g=4.0+-0.3. We find a
mean distance of 7.4+-1.8 kpc to M 2-29 at which the M_V=-0.9 mag CSPN could
potentially hide a subgiant luminosity or fainter companion. A companion would
help explain the multiple similarities with D'-type symbiotic stars whose outer
nebulae are thought to be bona-fide PNe. The 7.4 kpc distance, oxygen abundance
of 8.3 dex and Galactic coordinates (l=4.0, b=-3.0) prove that M 2-29 is a
Galactic Bulge PN and not a Halo PN as commonly misconceived.Comment: 15 pages, 14 figures, 7 tables. Accepted for publication in A\&
Determinants of impact : towards a better understanding of encounters with the arts
The article argues that current methods for assessing the impact of the arts are largely based on a fragmented and incomplete understanding of the cognitive, psychological and socio-cultural dynamics that govern the aesthetic experience. It postulates that a better grasp of the interaction between the individual and the work of art is the necessary foundation for a genuine understanding of how the arts can affect people. Through a critique of philosophical and empirical attempts to capture the main features of the aesthetic encounter, the article draws attention to the gaps in our current understanding of the responses to art. It proposes a classification and exploration of the factorsâsocial, cultural and psychologicalâthat contribute to shaping the aesthetic experience, thus determining the possibility of impact. The âdeterminants of impactâ identified are distinguished into three groups: those that are inherent to the individual who interacts with the artwork; those that are inherent to the artwork; and âenvironmental factorsâ, which are extrinsic to both the individual and the artwork. The article concludes that any meaningful attempt to assess the impact of the arts would need to take these âdeterminants of impactâ into account, in order to capture the multidimensional and subjective nature of the aesthetic experience
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