4,261 research outputs found
Review of the occupational health and safety of Britainâs ethnic minorities
This report sets out an evidence-based review on work-related health and safety issues relating to black and
minority ethnic groups. Data included available statistical materials and a systematic review of published research
and practice-based reports.
UK South Asians are generally under-represented within the most hazardous occupational groups. They have
lower accident rates overall, while Black Caribbean workers rates are similar to the general population;
Bangladeshi and Chinese workers report lowest workplace injury rates
UK South Asian people exhibit higher levels of limiting long-term illness (LLI) and self reported poor health than the
general population while Black Africans and Chinese report lower levels. Ethnic minority workers with LLI are more
likely than whites to withdraw from the workforce, or to experience lower wage rates.
Some of these findings conflict with evidence of differentials from USA, Europe and Australasia, but there is a
dearth of effective primary research or reliable monitoring data from UK sources.
There remains a need to improve monitoring and data collection relating to black and ethnic minority populations
and migrant workers. Suggestions are made relating to workshops on occupational health promotion programmes
for ethnic minorities, and ethnic minority health and safety 'Beacon' sites
Aneuploidy in oocytes is prevented by sustained CDK1 activity through degron masking in cyclin B1
Successful mitosis requires that cyclin B1:CDK1 kinase activity remains high until chromosomes are correctly aligned on the mitotic spindle. It has therefore been unclear why, in mammalian oocyte meiosis, cyclin B1 destruction begins before chromosome alignment is complete. Here, we resolve this paradox and show that mouse oocytes exploit an imbalance in the ratio of cyclin B1 to CDK1 to control CDK1 activity; early cyclin B1 destruction reflects the loss of an excess of non-CDK1-bound cyclin B1 in late prometaphase, while CDK1-bound cyclin B1 is destroyed only during metaphase. The ordered destruction of the two forms of cyclin B1 is brought about by a previously unidentified motif that is accessible in free cyclin B1 but masked when cyclin B1 is in complex with CDK1. This protects the CDK1-bound fraction from destruction in prometaphase, ensuring a period of prolonged CDK1 activity sufficient to achieve optimal chromosome alignment and prevent aneuploidy
Large Scale Structure traced by Molecular Gas at High Redshift
We present observations of redshifted CO(1-0) and CO(2-1) in a field
containing an overdensity of Lyman break galaxies (LBGs) at z=5.12. Our
Australia Telescope Compact Array observations were centered between two
spectroscopically-confirmed z=5.12 galaxies. We place upper limits on the
molecular gas masses in these two galaxies of M(H_2) <1.7 x 10^10 M_sun and
<2.9 x 10^9 M_sun (2 sigma), comparable to their stellar masses. We detect an
optically-faint line emitter situated between the two LBGs which we identify as
warm molecular gas at z=5.1245 +/- 0.0001. This source, detected in the CO(2-1)
transition but undetected in CO(1-0), has an integrated line flux of 0.106 +/-
0.012 Jy km/s, yielding an inferred gas mass M(H_2)=(1.9 +/- 0.2) x 10^10
M_sun. Molecular line emitters without detectable counterparts at optical and
infrared wavelengths may be crucial tracers of structure and mass at high
redshift.Comment: 4 pages, accepted for publication in ApJ Letter
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Genetics of Degenerative Cervical Myelopathy: A Systematic Review and Meta-Analysis of Candidate Gene Studies
Degenerative cervical myelopathy (DCM) is estimated to be the most common cause of adult spinal cord impairment. Evidence that is suggestive of a genetic basis to DCM has been increasing over the last decade. A systematic search was conducted in MEDLINE, EMBASE, Cochrane, and HuGENet databases from their origin up to 14th December 2019 to evaluate the role of single genes in DCM in its onset, clinical phenotype, and response to surgical intervention. The initial search yielded 914 articles, with 39 articles being identified as eligible after screening. We distinguish between those contributing to spinal column deterioration and those contributing to spinal cord deterioration in assessing the evidence of genetic contributions to DCM. Evidence regarding a total of 28 candidate genes was identified. Of these, 22 were found to have an effect on the radiological onset of spinal column disease, while 12 genes had an effect on clinical onset of spinal cord disease. Polymorphisms of eight genes were found to have an effect on the radiological severity of DCM, while three genes had an effect on clinical severity. Polymorphisms of six genes were found to have an effect on clinical response to surgery in spinal cord disease. There are clear genetic effects on the development of spinal pathology, the central nervous system (CNS) response to bony pathology, the severity of both bony and cord pathology, and the subsequent response to surgical intervention. Work to disentangle the mechanisms by which the genes that are reviewed here exert their effects, as well as improved quality of evidence across diverse populations is required for further investigating the genetic contribution to DCM
Pseudobulges in the Disk Galaxies NGC 7690 and NGC 4593
We present Ks-band surface photometry of NGC 7690 (Hubble type Sab) and NGC
4593 (SBb). We find that, in both galaxies, a major part of the "bulge" is as
flat as the disk and has approximately the same color as the inner disk. In
other words, the "bulges" of these galaxies have disk-like properties. We
conclude that these are examples of "pseudobulges" -- that is, products of
secular dynamical evolution. Nonaxisymmetries such as bars and oval disks
transport disk gas toward the center. There, star formation builds dense
stellar components that look like -- and often are mistaken for -- merger-built
bulges but that were constructed slowly out of disk material. These
pseudobulges can most easily be recognized when, as in the present galaxies,
they retain disk-like properties. NGC 7690 and NGC 4593 therefore contribute to
the growing evidence that secular processes help to shape galaxies.
NGC 4593 contains a nuclear ring of dust that is morphologically similar to
nuclear rings of star formation that are seen in many barred and oval galaxies.
The nuclear dust ring is connected to nearly radial dust lanes in the galaxy's
bar. Such dust lanes are a signature of gas inflow. We suggest that gas is
currently accumulating in the dust ring and hypothesize that the gas ring will
starburst in the future. The observations of NGC 4593 therefore suggest that
major starburst events that contribute to pseudobulge growth can be episodic.Comment: 10 pages, 3 Postscript figures; requires emulateapj.cls,
apjfonts.sty, and psfig.sty; accepted for publication in ApJ; for a version
with full resolution figures, see
http://chandra.as.utexas.edu/~kormendy/n7690.pd
Galactic contamination in the QMAP experiment
We quantify the level of foreground contamination in the QMAP Cosmic
Microwave Background (CMB) data with two objectives: (a) measuring the level to
which the QMAP power spectrum measurements need to be corrected for foregrounds
and (b) using this data set to further refine current foreground models. We
cross-correlate the QMAP data with a variety of foreground templates. The 30
GHz Ka-band data is found to be significantly correlated with the Haslam 408
MHz and Reich and Reich 1420 MHz synchrotron maps, but not with the Diffuse
Infrared Background Experiment (DIRBE) 240, 140 and 100 micron maps or the
Wisconsin H-Alpha Mapper (WHAM) survey. The 40 GHz Q-band has no significant
template correlations. We discuss the constraints that this places on
synchrotron, free-free and dust emission. We also reanalyze the
foreground-cleaned Ka-band data and find that the two band power measurements
are lowered by 2.3% and 1.3%, respectively.Comment: 4 ApJL pages, including 4 figs. Color figures and data at
http://www.hep.upenn.edu/~angelica/foreground.html#qmap or from
[email protected]
Herschel-PACS Observations of Far-IR CO Line Emission in NGC 1068: Highly Excited Molecular Gas in the Circumnuclear Disk
We report the detection of far-IR CO rotational emission from the
prototypical Seyfert 2 galaxy NGC 1068. Using Herschel-PACS, we have detected
11 transitions in the J_upper=14-30 (E_upper/k_B = 580-2565 K) range, all of
which are consistent with arising from within the central 10" (700 pc). The
detected transitions are modeled as arising from 2 different components: a
moderate excitation (ME) component close to the galaxy systemic velocity, and a
high excitation (HE) component that is blueshifted by ~80 km s^{-1}. We employ
a large velocity gradient (LVG) model and derive n_H2~10^{5.6} cm^{-3},
T_kin~170 K, and M_H2~10^{6.7} M_sun for the ME component, and n_H2~10^{6.4}
cm^{-3}, T_kin~570 K, and M_H2~10^{5.6} M_sun for the HE component, although
for both components the uncertainties in the density and mass are plus/minus
(0.6-0.9) dex. We compare the CO line profiles with those of other molecular
tracers observed at higher spatial and spectral resolution, and find that the
ME transitions are consistent with these lines arising in the ~200 pc diameter
ring of material traced by H_2 1-0 S(1) observations. The blueshift of the HE
lines may also be consistent with the bluest regions of this H_2 ring, but a
better kinematic match is found with a clump of infalling gas ~40 pc north of
the AGN. We discuss the prospects of placing the HE component near the AGN, and
conclude that while the moderate thermal pressure precludes an association with
the ~1 pc radius H_2O maser disk, the HE component could potentially be located
only a few parsecs more distant from the AGN, and might then provide the
N_H~10^{25} cm^{-2} column obscuring the nuclear hard X-rays. Finally, we also
report sensitive upper limits extending up to J_upper=50, which place
constraints on a previous model prediction for the CO emission from the X-ray
obscuring torus. [Abridged]Comment: 20 pages, 10 figures. Accepted for publication in Ap
Variation in plasma oxidative status and testosterone level in relation to egg-eviction effort and age of brood-parasitic common cuckoo nestlings
To avoid competition for parental care, brood-parasitic Common Cuckoo (Cuculus canorus) nestlings evict all of the host's eggs and nestlings within a few days after hatching. Little is known about the physiological effects of eviction behavior on the cuckoo nestling's oxidative balance or about age-related variation in plasma oxidative status and testosterone level of developing birds. We examined whether the cuckoo nestling's plasma oxidative status was related to prior effort in eviction and quantified variation in the level of reactive oxygen metabolites, of nonenzymatic antioxidant capacity, and of testosterone concentration in plasma at various phases of the cuckoo's development. Levels of both reactive oxygen metabolites and antioxidant capacity were greater in older than in younger nestlings, suggesting that younger nestlings effectively counterbalance their increased production of free radicals, whereas, near fledging, levels of reactive oxygen metabolites increase despite improved antioxidant capacity. Possibly, overall energy expenditure increases with age and elevates the production of reactive oxygen species to a rate higher than what the antioxidant system could eliminate. Plasma testosterone level was the highest at nestlings' intermediate phase of growth. High levels of testosterone may be required during the period of fastest growth, and when the growth rate levels off near fledging, testosterone levels may also decline. Cuckoo chicks that evicted more host eggs from steeper nests had higher plasma levels of reactive oxygen metabolites shortly after the eviction period, suggesting that eviction is costly in terms of an increased level of oxidative stress. Para evitar la competencia por el cuidado parental, los polluelos parĂĄsitos de nidada de Cuculus canorus desalojan todos los huevos y los polluelos del hospedador a los pocos dĂas despuĂ©s de la eclosiĂłn. Se sabe poco sobre los efectos fisiolĂłgicos del comportamiento de desalojo en el balance oxidativo de los polluelos de C. canorus o sobre la variaciĂłn en el estatus oxidativo del plasma y el nivel de testosterona relacionado con la edad de las aves en desarrollo. Examinamos si el estatus oxidativo del plasma de los polluelos de C. canorus se relacionaba con un esfuerzo previo de desalojo y cuantificamos la variaciĂłn en el nivel de metabolitos reactivos de oxĂgeno, la capacidad antioxidante no enzimĂĄtica y la concentraciĂłn de testosterona en el plasma en varias fases del desarrollo de C. canorus. Tanto los niveles de metabolitos reactivos de oxĂgeno como la capacidad antioxidante fueron superiores en los polluelos de mayor edad que en los mĂĄs jĂłvenes, lo que sugiere que los polluelos de menor edad contrarrestan eficazmente el aumento de la producciĂłn de radicales libres, mientras que, cuando se aprĂłximan al abandono del nido, los niveles de metabolitos reactivos de oxĂgeno aumentan a pesar de una mejora en la capacidad antioxidante. Posiblemente, el gasto total de energĂa se incrementa con la edad, elevĂĄndose la producciĂłn de formas reactivas de oxĂgeno a una tasa mayor de la que el sistema antioxidante puede eliminar. El nivel de testosterona en el plasma fue mĂĄximo en la fase intermedia del crecimiento de los polluelos. Pueden requerirse altos niveles de testosterona durante el perĂodo de mayor crecimiento y, cuando la tasa de crecimiento se estabiliza cerca del abandono del nido, los niveles de testosterona tambiĂ©n podriĂĄn disminuir. Los polluelos de C. canorus que desalojaron mĂĄs huevos del hospedador en nidos con una estructura mĂĄs empinada tuvieron niveles de plasma de metabolitos reactivos de oxĂgeno en plasma mĂĄs altos poco despuĂ©s del perĂodo de desalojo, sugiriendo que el desalojo es costoso en tĂ©rminos de un incremento en el nivel de estrĂ©s oxidativo
Two-loop RGEs with Dirac gaugino masses
The set of renormalisation group equations to two loop order for general
supersymmetric theories broken by soft and supersoft operators is completed. As
an example, the explicit expressions for the RGEs in a Dirac gaugino extension
of the (N)MSSM are presented.Comment: 10 pages + 24 pages of RGEs in appendix; no figure
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