4,380 research outputs found
The co-construction of energy provision and everyday practice: integrating heat pumps in social housing in England
Challenges of energy security, low carbon transitions, and electricity network constraints have led to a shift to new, efficient technologies for household energy services. Studies of such technological innovations usually focus on consumer information and changes in behaviour to realise their full potential. We suggest that regarding such technologies in existing energy provision systems opens up questions concerning how and why such interventions are delivered. We argue that we must understand the ways by which energy systems are co-constituted through the habits and expectations of households, their technologies and appliances, alongside arrangements associated with large-scale socio-technical infrastructures. Drawing on research with air-source-to-water heat pumps (ASWHP), installed as part of a large trans-disciplinary, utility-led research and demonstration project in the north of England, we investigate how energy services provision and everyday practice shapes new technologies uptake, and how such technologies mediate and reconfigure relations between users, providers and infrastructure networks. While the installation of ASWHP has led to role differentiation through which energy services are provided, the space for new forms of co-provision to emerge is limited by existing commitments to delivering energy services. Simultaneously, new forms of interdependency emerge between users, providers and intermediaries through sites of installation, instruction, repair and feedback. We find that although new technologies do lead to the rearrangement of practices, this is often disrupted by obduracy in the conventions and habits around domestic heating and hot water practices that have been established in relation to existing systems of provision. Rather being simply a matter of increasing levels of knowledge in order to ensure that such technologies are adopted effi ciently and effectively, our paper demonstrates how systemic arrangements of energy provision and everyday practice are co-implicated in socio-technical innovation by changing the nature of energy supply and use
Palomar 13: An Unusual Stellar System in the Galactic Halo
We have measured Keck/HIRES radial velocities for 30 candidate red giants in
the direction of Palomar 13: an object traditionally cataloged as a compact,
low-luminosity globular cluster. From a sample of 21 confirmed members, we find
a systemic velocity of 24.1 km/s and a projected, intrinsic velocity dispersion
of 2.2 km/s. Although small, this dispersion is several times larger than that
expected for a globular cluster of this luminosity and central concentration.
Taken at face value, this dispersion implies a mass-to-light ratio of ~ 40 (in
solar units) based on the best-fit King-Michie model. The surface density
profile of Palomar 13 also appears to be anomalous among Galactic globular
clusters -- depending upon the details of background subtraction and
model-fitting, Palomar 13 either contains a substantial population of
"extra-tidal" stars, or it is far more spatially extended than previously
suspected. The full surface density profile is equally well-fit by a
King-Michie model having a high concentration and large tidal radius, or by a
NFW model. We examine -- and tentatively reject -- a number of possible
explanations for the observed characteristics of Palomar 13 (e.g., velocity
"jitter" among the red giants, spectroscopic binary stars, non-standard mass
functions, modified Newtonian dynamics), and conclude that the two most
plausible scenarios are either catastrophic heating during a recent
perigalacticon passage, or the presence of a massive dark halo. Thus, the
available evidence suggests that Palomar 13 is either a globular cluster which
is now in the process of dissolving into the Galactic halo, or a faint,
dark-matter-dominated stellar system (ABRIDGED).Comment: 31 pages, 13 postscript figures and 1 color gif image. Also available
at http://www.physics.rutgers.edu/ast/ast-rap.html. Accepted for publication
in the Astrophysical Journa
GENOMICS OF ENDOGLIN PATHWAY IN PREECLAMPSIA
THE GENOMICS OF ENDOGLIN PATHWAY IN PREECLAMPSIA
Mandy J. Bell, PhD, RN
University of Pittsburgh, 2012
Preeclampsia is a pregnancy disorder that greatly impacts maternal and fetal/neonatal health and wellbeing. This case-control candidate gene association study investigated endoglin pathway genetic variation and its association with preeclampsia. Tagging single nucleotide polymorphisms (tSNPs) in ENG, TGFβ1, TGFβR1, ALK1, and TGFβR2 were genotyped with iPLEX® and TaqMan® in maternal/fetal dyads. The Prenatal Exposures and Preeclampsia Prevention study provided maternal DNA extracted from peripherally collected white blood cell pellets, along with umbilical cord serum we used for fetal DNA extraction. Data on 355 white (181 cases/174 controls) and 60 black (30 cases/30 controls) women matched on ancestry, age, and parity were analyzed. Separate subgroup allele/genotype/haplotype tests were conducted with Chi-square or Fisher’s exact tests. Binary logistic regression provided odds ratios for tSNPs with significant genotype tests. Analysis of maternal/fetal dyads was not conducted, because unlike the maternal samples, the fetal samples did not provide a quality template suitable for iPLEX® data collection. In white women, variation in ENG (rs11792480, rs10121110) and TGFβR2 (rs6550005) was associated with preeclampsia. Allelic frequency distributions in rs11792480, rs10121110, and rs6550005 were significantly different among cases and controls while genotype distributions of rs10121110 and rs6550005 were further associated with preeclampsia (p-values < .05). For rs10121110, women with the AA genotype were 2.290 times more likely to develop preeclampsia compared to the GG genotype (99% CI [1.022, 5.133], p = .008). ENG haplotype TACGA, which contains rs11792480 and rs10121110 risk alleles, was also over-represented in cases (p = .022). In black women, variation in TGFβ1 (rs4803455, rs4803457), TGFβR1 (rs10739778), and TGFβR2 (rs6550005, rs1346907, rs877572) was associated with preeclampsia. Allelic frequency distributions in rs10739778, rs6550005, rs1346907, and rs877572 were significantly different among cases and controls while genotype distributions of rs10739778, rs4803455, and rs4803457 were further associated with preeclampsia (p-values < .05). For rs4803457, women with the CT genotype were 7.437 more times likely to develop preeclampsia compared to the CC genotype (99% CI [1.192, 46.408], p = .005). These results demonstrate that variation in ENG pathway genes is associated with preeclampsia, with different genes from the same pathway contributing to preeclampsia in white compared to black women
Fostering active network management through SMEs’practises
Managing the electricity network through ‘smart grid’ systems is a key strategy to address challenges of energy security, low carbon transitions and the replacement of ageing infrastructure networks in the UK. Small and medium enterprises (SMEs) have a significant role in shaping patterns of energy consumption. Understanding how their activities interrelate with changes in electricity systems is critical for active network management. A significant challenge for the transformation of electricity systems involves comprehending the complexity that stems from the variety of commercial activities and diversity of social and organizational practises among SMEs that interact with material infrastructures. We engage with SMEs to consider how smart grid interventions ‘fit’ into everyday operational activities. Drawing on analysis of empirical data on electricity use, smart metre data, surveys, interviews and ‘energy tours’ with SMEs to understand lighting, space heating and cooling, refrigeration and IT use, this paper argues for experimenting with the use of practise theory as a framework for bringing together technical and social aspects of energy use in SMEs. This approach reveals that material circumstances and temporal factors shape current energy demand among SMEs, with ‘connectedness’ an emergent factor
Loss of CSMD1 expression is associated with high tumour grade and poor survival in invasive ductal breast carcinoma
International audienceCUB and SUSHI multiple domain protein 1 () is a candidate tumour suppressor gene that maps to chromosome 8p23, a region deleted in many tumour types including 50% of breast cancers. CSMD1 has homologies to proteins implicated in carcinogenesis. We aimed to study the expression pattern of the CSMD1 protein and evaluate its prognostic importance in invasive ductal carcinoma (IDC). An anti-CSMD1 antibody was developed and validated. The expression pattern of CSMD1 in normal breast and IDC samples was investigated by immunohistochemistry in 275 patients. Univariate and multivariate Cox regression analyses were performed. In normal breast duct epithelial cells, luminal, membranous and cytoplasmic CSMD1 staining was identified. Reduced expression of CSMD1 was detected in 79/275 (28.7%) of IDC cases. Low CSMD1 expression was significantly associated with high tumour grade ( = 0.003). CSMD1 expression was associated with overall survival (OS; HR = 0.607, 95%CI: 0.4-0.91, = 0.018) but not with disease-free survival (DFS; HR = 0.81, 95%CI: 0.46-1.43, = 0.48). Multivariate analysis showed that CSMD1, together with Nottingham Prognostic Index, was considered an independent predictor of OS (HR = 0.607, 95%CI: 0.4-0.91, = 0.018) but not DFS (HR = 0.84, 95%CI: 0.46-1.5, = 0.573). Reduction of CSMD1 expression was significantly associated with high tumour grade and decreased OS. Therefore, our results support the idea that is a tumour suppressor gene and suggest its possible use as a new prognostic biomarker. The membrane expression pattern of CSMD1 suggests that it may be a receptor or co-receptor involved in the process of signal transduction
Clumpy Galaxies in CANDELS. I. The Definition of UV Clumps and the Fraction of Clumpy Galaxies at 0.5<z<3
Although giant clumps of stars are crucial to galaxy formation and evolution,
the most basic demographics of clumps are still uncertain, mainly because the
definition of clumps has not been thoroughly discussed. In this paper, we study
the basic demographics of clumps in star-forming galaxies (SFGs) at 0.5<z<3,
using our proposed physical definition that UV-bright clumps are discrete
star-forming regions that individually contribute more than 8% of the
rest-frame UV light of their galaxies. Clumps defined this way are
significantly brighter than the HII regions of nearby large spiral galaxies,
either individually or blended, when physical spatial resolution and
cosmological dimming are considered. Under this definition, we measure the
fraction of SFGs that contain at least one off-center clump (Fclumpy) and the
contributions of clumps to the rest-frame UV light and star formation rate of
SFGs in the CANDELS/GOODS-S and UDS fields, where our mass-complete sample
consists of 3239 galaxies with axial ratio q>0.5. The redshift evolution of
Fclumpy changes with the stellar mass (M*) of the galaxies. Low-mass
(log(M*/Msun)<9.8) galaxies keep an almost constant Fclumpy of about 60% from
z~3.0 to z~0.5. Intermediate-mass and massive galaxies drop their Fclumpy from
55% at z~3.0 to 40% and 15%, respectively, at z~0.5. We find that (1) the trend
of disk stabilization predicted by violent disk instability matches the Fclumpy
trend of massive galaxies; (2) minor mergers are a viable explanation of the
Fclumpy trend of intermediate-mass galaxies at z<1.5, given a realistic
observability timescale; and (3) major mergers are unlikely responsible for the
Fclumpy trend in all masses at z<1.5. The clump contribution to the rest-frame
UV light of SFGs shows a broad peak around galaxies with log(M*/Msun)~10.5 at
all redshifts, possibly linked to the molecular gas fraction of the galaxies.
(Abridged)Comment: 22 pages, 15 figures. Appeared in ApJ (2015, 800, 39). A few typos
correcte
Antitumor activity and safety of the PARP inhibitor rucaparib in patients with high grade ovarian carcinoma and a germline or somatic BRCA1 or BRCA2 mutation: integrated analysis of data from Study 10 and ARIEL2
Objective:
An integrated analysis was undertaken to characterize the antitumor activity and safety profile of the oral poly(ADP-ribose) polymerase inhibitor rucaparib in patients with relapsed high-grade ovarian carcinoma (HGOC).
Methods:
Eligible patients from Study 10 (NCT01482715) and ARIEL2 (NCT01891344) who received a starting dose of oral rucaparib 600 mg twice daily (BID) with or without food were included in these analyses. The integrated efficacy population included patients with HGOC and a deleterious germline or somatic BRCA1 or BRCA2 (BRCA1/2) mutation who received at least two prior chemotherapies and were sensitive, resistant, or refractory to platinum-based chemotherapy. The primary endpoint was investigator-assessed confirmed objective response rate (ORR). Secondary endpoints included duration of response (DOR) and progression-free survival (PFS). The integrated safety population included patients with HGOC who received at least one dose of rucaparib 600 mg BID, irrespective of BRCA1/2 mutation status and prior treatments.
Results:
In the efficacy population (n = 106), ORR was 53.8% (95% confidence interval [CI], 43.8–63.5); 8.5% and 45.3% of patients achieved complete and partial responses, respectively. Median DOR was 9.2 months (95% CI, 6.6–11.6). In the safety population (n = 377), the most frequent treatment-emergent adverse events (AEs) were nausea, asthenia/fatigue, vomiting, and anemia/hemoglobin decreased. The most common grade ≥ 3 treatment-emergent AE was anemia/hemoglobin decreased. Treatment-emergent AEs led to treatment interruption, dose reduction, and treatment discontinuation in 58.6%, 45.9%, and 9.8% of patients, respectively. No treatment-related deaths occurred.
Conclusions:
Rucaparib has antitumor activity in advanced BRCA1/2-mutated HGOC and a manageable safety profile
3D-HST+CANDELS : the evolution of the galaxy size-mass distribution since z=3
Spectroscopic+photometric redshifts, stellar mass estimates, and rest-frame colors from the 3D-HST survey are combined with structural parameter measurements from CANDELS imaging to determine the galaxy size-mass distribution over the redshift range 0 < z < 3. Separating early- and late-type galaxies on the basis of star-formation activity, we confirm that early-type galaxies are on average smaller than late-type galaxies at all redshifts, and we find a significantly different rate of average size evolution at fixed galaxy mass, with fast evolution for the early-type population, R eff∝(1 + z)–1.48, and moderate evolution for the late-type population, R eff∝(1 + z)-0.75Peer reviewedFinal Accepted Versio
The Progenitors of the Compact Early-Type Galaxies at High-Redshift
We use GOODS and CANDELS images to identify progenitors of massive (log M >
10 Msun) compact "early-type" galaxies (ETGs) at z~1.6. Since merging and
accretion increase the size of the stellar component of galaxies, if the
progenitors are among known star-forming galaxies, these must be compact
themselves. We select candidate progenitors among compact Lyman-break galaxies
at z~3 based on their mass, SFR and central stellar density and find that these
account for a large fraction of, and possibly all, compact ETGs at z~1.6. We
find that the average far-UV SED of the candidates is redder than that of the
non-candidates, but the optical and mid-IR SED are the same, implying that the
redder UV of the candidates is inconsistent with larger dust obscuration, and
consistent with more evolved (aging) star-formation. This is in line with other
evidence that compactness is a sensitive predictor of passivity among
high-redshift massive galaxies. We also find that the light distribution of
both the compact ETGs and their candidate progenitors does not show any
extended "halos" surrounding the compact "core", both in individual images and
in stacks. We argue that this is generally inconsistent with the morphology of
merger remnants, even if gas-rich, as predicted by N-body simulations. This
suggests that the compact ETGs formed via highly dissipative, mostly gaseous
accretion of units whose stellar components are very small and undetected in
the HST images, with their stellar mass assembling in-situ, and that they have
not experienced any major merging until the epoch of observations at z~1.6.Comment: 25 pages, 20 figures; Accepted for publication in Ap
Smooth(er) Stellar Mass Maps in CANDELS: Constraints on the Longevity of Clumps in High-redshift Star-forming Galaxies
We perform a detailed analysis of the resolved colors and stellar populations
of a complete sample of 323 star-forming galaxies at 0.5 < z < 1.5, and 326
star-forming galaxies at 1.5 < z < 2.5 in the ERS and CANDELS-Deep region of
GOODS-South. Galaxies were selected to be more massive than 10^10 Msun and have
specific star formation rates above 1/t_H. We model the 7-band optical ACS +
near-IR WFC3 spectral energy distributions of individual bins of pixels,
accounting simultaneously for the galaxy-integrated photometric constraints
available over a longer wavelength range. We analyze variations in rest-frame
color, stellar surface mass density, age, and extinction as a function of
galactocentric radius and local surface brightness/density, and measure
structural parameters on luminosity and stellar mass maps. We find evidence for
redder colors, older stellar ages, and increased dust extinction in the nuclei
of galaxies. Big star-forming clumps seen in star formation tracers are less
prominent or even invisible on the inferred stellar mass distributions.
Off-center clumps contribute up to ~20% to the integrated SFR, but only 7% or
less to the integrated mass of all massive star-forming galaxies at z ~ 1 and z
~ 2, with the fractional contributions being a decreasing function of
wavelength used to select the clumps. The stellar mass profiles tend to have
smaller sizes and M20 coefficients, and higher concentration and Gini
coefficients than the light distribution. Our results are consistent with an
inside-out disk growth scenario with brief (100 - 200 Myr) episodic local
enhancements in star formation superposed on the underlying disk.
Alternatively, the young ages of off-center clumps may signal inward clump
migration, provided this happens efficiently on the order of an orbital
timescale.Comment: Accepted by The Astrophysical Journal, 27 pages, 1 table, 16 figure
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