212 research outputs found
Moderate Intensity Exercise Training Improves Cardiorespiratory Fitness in Women
Among women, there is an increased prevalence of sedentary lifestyle and less participation in physical activity at levels recommended by the Surgeon General. As a result, women have been identified as a target group in public health initiatives to increase physical activity. The health-related benefits of habitual, moderate intensity physical activity are well documented in the epidemiological literature, but less is known about the effect of such physical activity on cardiorespiratory fitness. Our hypothesis was that moderate and vigorous exercise training regimens of similar estimated energy expenditure would result in similar changes in cardiorespiratory fitness. Eighteen sedentary premenopausal women with the following baseline characteristics [x ± SE]: maximal oxygen consumption (VO2max) = 29.5 ± 1.5ml â kg-1 â min-1; age=33 ± 1 years; height=162.6 ± 0.9 cm; mass = 62.7 ± 2.3 kg, were randomly assigned to either vigorous (HI, 80% VO2max, n=10) or moderate intensity (MOD, 40% VO2max, n=8) cycle ergometer training groups. Exercise training was conducted 3-4 (3.37 ± 0.05) days/week for 12 weeks in a supervised and progressive manner, with estimated exercise energy expenditure equated across both training groups. VO2max and time to exhaustion increased significantly in both groups (p\u3c0.05), with no difference between groups. Both groups had lower (p\u3c0.05) posttraining submaximal heart rates (HR), respiratory exchange ratios (RER), and ratings of perceived exertion (RPE) during graded exercise testing, with no significant differences between the groups in posttraining values. Women participating in moderate intensity exercise training as recommended in basic public health guidelines demonstrate an increase in cardiorespiratory fitness similar to that elicited by vigorous training
Case studies on the socio-economic characteristics and lifestyles subsistence and informal fisheries in South Africa
To develop a management strategy for informal fishers, a necessary first step is information about the nature of these fishers, their numbers and their socio-economic status. To accomplish this, a survey of socio-economic conditions and use of marine resources was undertaken in 1999 at 20 localities where fishing occurs around the coast of South Africa, concentrating on subsistence or small- to micro-scale artisanal commercial fishers. In each locality, 16â31 âfisher householdsâ were surveyed by questionnaires, focus-group discussions and interviews with key informants. Demographic analyses revealed a low level of migrancy (~5%), an average of 5.3 persons per household and a mean age of 27. Only ~20% of fishers were women and ~15% were children. Poverty was prevalent: unemployment averaged 40.3% (much higher than the national norm of 29.3%). Mean adult equivalent income per month spanned R193âR735 among regions, and was not correlated with size of settlement. Education levels were low, only ~33% of people >20 years old having completed primary school. Migrancy was highest in rural areas (but still much less than the national norm), intermediate in towns and least in metropolitan areas. Household size, participation of women and poverty all followed similar trends. Comparing regions, the East Coast and the province of KwaZulu-Natal had higher migrancy rates, larger household sizes, greater poverty, and greater participation by women in fishing, than on the South and West coasts. Household expenditure on food was ~R450 per month on the South-East and KwaZulu-Natal coasts and ~R750 on the West Coast, and exceeded 60% of income (a measure of âfood securityâ) in about half the households surveyed. Harvested resources were sold, consumed or used as bait. In all regions, the two most frequently harvested resources were fish (mostly sold, predominantly fished by men) and intertidal rocky-shore invertebrates (largely consumed, and involving women to a greater degree). On the West Coast, rock lobster Jasus lalandii was the third-most important resource, but on the South and KwaZulu-Natal coasts this species was replaced by estuarine invertebrates. Abalone Haliotis midae, oysters, sandy-beach invertebrates and kelp or seaweeds made up the balance. Diversity of harvested resources increased west to east, following biogeographic trends. The resources could be divided into those of high value (rock lobsters, abalone and, to a lesser extent, fish) and those of lower value (such as limpets, mussels and bait organisms). It is argued that high-value resources are best used to create micro- and small-scale commercial enterprises that can serve to uplift poor fishers. Lowvalue resources constitute subsistence resources, for which preferential rights should be established for subsistence fishers, including development of exclusive-use zones where necessary. Emerging characteristics of fishing communities that were helpful in defining subsistence fishers in the South African context were poverty, harvest for self-use (whether by consumption or sale to meet basic needs of food security), use of low-technology gear, and concentration of effort on or from shores or in estuaries. At least portions of the catches of all resources are sold, and the majority of equipment is purchased, so any definition of subsistence fishers cannot exclude those who sell part of their catch or do not use hand-made equipment. Some success was evident with co-management, encouraging further exploration of this style of management for subsistence fishers. Keywords: informal fishers, socio-economics of fishers, subsistence fishersAfrican Journal of Marine Science 2002, 24: 439â46
Assessment of resource availability and sustainability for subsistence fishers in South Africa, with a review of resource management procedures
The availability of resources and their suitability for subsistence and small-scale commercial fishers in South Africa were assessed and appropriate options for the management of resources recommended. Assessment of current resource utilization and recommendations for future subsistence and/or small-scale commercial use were based on information gathered during a nationwide survey of 144 subsistence fishing communities in South Africa and a review of relevant published and unpublished literature. Current patterns of resource use in three regions of the coast (West, South and East coasts) revealed that most true subsistence fisheries occur in the eastern half of the country. These fisheries are primarily focused on invertebrate species found on intertidal rocky shores and sandy beaches, or in estuaries. Fish are harvested by rod or handline, netting or traditional fishing methods (fishtraps, spearing, baited baskets). No ânewâ or previously underutilized resources were identified as suitable for subsistence fishing in any of the three regions. The potential for several new small-scale commercial fisheries was identified, but the need to retain certain resources for subsistence fisheries (rather than converting them to small-scale commercial fisheries) was evident in certain areas. Resources with high commercial value were not considered suitable for subsistence fishing, but rather for the introduction of small-scale commercial fisheries. The overall management strategy for the subsistence sector, which is currently in the process of being developed, must ensure sufficient flexibility to be able to take into account regional and site-specific requirements. It will also need to develop co-management structures, protect traditional fishing practices, avoid user conflict and provide for no-take areas, all within the framework of sustainable resource utilization.Keywords: estuarine resources, fisheries management, intertidal resources, subsistence fisheries, subtidal resourcesAfrican Journal of Marine Science 2002, 24: 489â50
The kinematics and chemical stratification of the Type Ia supernova remnant 0519-69.0
We present an analysis of the XMM-Newton and Chandra X-ray data of the young
Type Ia supernova remnant 0519-69.0 in the Large Magellanic Cloud. We used data
from both the Chandra ACIS and XMM-Newton EPIC-MOS instruments, and high
resolution X-ray spectra obtained with the XMM-Newton Reflection Grating
Spectrometer. The Chandra data show that there is a radial stratification of
oxygen, intermediate mass elements and iron, with the emission from more
massive elements more toward the center. Using a deprojection technique we
measure a forward shock radius of 4.0(3) pc and a reverse shock radius of
2.7(4) pc. We took the observed stratification of the shocked ejecta into
account in the modeling of the X-ray spectra with multi-component NEI models,
with the components corresponding to layers dominated by one or two elements.
An additional component was added in order to represent the ISM, which mostly
contributed to the continuum emission. This model fits the data well, and was
also employed to characterize the spectra of distinct regions extracted from
the Chandra data. From our spectral analysis we find that the fractional masses
of shocked ejecta for the most abundant elements are: M(O)=32%, M(Si/S)=7%/5%,
M(Ar+Ca)=1%, and M(Fe) = 55%. From the continuum component we derive a
circumstellar density of nH= 2.4(2)/cm^3. This density, together with the
measurements of the forward and reverse shock radii suggest an age of 450+/-200
yr,somewhat lower than, but consistent with the estimate based on the optical
light echo (600+/-200 yr). From the RGS spectra we measured a Doppler
broadening of sigma=1873+/-50 km/s, from implying a forward shock velocity of
vS = 2770+/-500 km/s. We discuss the results in the context of single
degenerate explosion models, using semi-analytical and numerical modeling, and
compare the characteristics of 0519-69.0 with those of other Type Ia supernova
remnants.Comment: Astronomy and Astrophysics in press. This version is the A&A accepted
version, which contains improved figures and an extended discussion sectio
The first year of SN 2004dj in NGC 2403
New BVRI photometry and optical spectroscopy of the Type IIp supernova 2004dj
in NGC 2403, obtained during the first year since discovery, are presented. The
progenitor cluster, Sandage 96, is also detected on pre-explosion frames. The
light curve indicates that the explosion occured about 30 days before
discovery, and the plateau phase lasted about +110 \pm 20 days after that. The
plateau-phase spectra have been modelled with the SYNOW spectral synthesis code
using H, NaI, TiII, ScII, FeII and BaII lines. The SN distance is inferred from
the Expanding Photosphere Method and the Standard Candle Method applicable for
SNe IIp. They resulted in distances that are consistent with each other as well
as earlier Cepheid- and Tully-Fisher distances. The average distance, D = 3.47
\pm 0.29 Mpc is proposed for SN 2004dj and NGC 2403. The nickel mass produced
by the explosion is estimated as 0.02 \pm 0.01 M_o. The SED of the progenitor
cluster is reanalysed by fitting population synthesis models to our observed
BVRI data supplemented by U and JKH magnitudes from the literature. The
chi^2-minimization revealed a possible "young" solution with cluster age T_{cl}
= 8 Myr, and an "old" solution with T_{cl} = 20 - 30 Myr. The "young" solution
would imply a progenitor mass M > 20 M_o, which is higher than the previously
detected progenitor masses for Type II SNe.Comment: 19 pages, accepted in MNRA
Discourses of student orientation to medical education programs
Background: Although medical studentsâ initial orientation is an important point of transition in medical education, there is a paucity of literature on the subject and major variations in the ways that different institutions orient incoming medical students to their programs. Methods: We conducted a discourse analysis of medical education orientation in the literature and on data from a survey of peer institutionsâ approaches to orientation. Results: These two discourses of orientation had clear similarities, in particular, the critical role of ceremony and symbols, and the focus on developing professionalism and physician identities. There were also differences between them, in particular, in the way that the discourse in the literature focused on the symbolic and professional aspects of orientation; something we have called âcultural orientationâ. Meanwhile, those who were responsible for orientation in their own institutions tended to focus on the practical and social dimensions. Conclusion: By examining how orientation has been described and discussed, we identify three domains of orientation: cultural, social, and practical. These domains are relatively distinct in terms of the activities associated with them, and in terms of who is involved in organizing and running these activities. We also describe orientation as a liminal activity system on the threshold of medical school where incoming students initially cross into the profession. Interestingly, this state of ambiguity also extends to the scholarship of orientation with only some of its aspects attracting formal enquiry, even though there is a growing interest in transitions in medical education as a whole. We hope, therefore, that this study can help to legitimize enquiry into orientation in all its forms and that it can begin to situate the role of orientation more firmly within the firmament of medical education practice and research
South Georgia blue whales five decades after the end of whaling
Blue whales Balaenoptera musculus at South Georgia were heavily exploited during 20th century industrial whaling, to the point of local near-extirpation. Although legal whaling for blue whales ceased in the 1960s, and there were indications of blue whale recovery across the wider Southern Ocean area, blue whales were seldom seen in South Georgia waters in subsequent years. We collated 30 yr of data comprising opportunistic sightings, systematic visual and acoustic surveys and photo-identification to assess the current distribution of blue whales in the waters surrounding South Georgia. Over 34000 km of systematic survey data between 1998 and 2018 resulted in only a single blue whale sighting, although opportunistic sightings were reported over that time period. However, since 2018 there have been increases in both sightings of blue whales and detections of their vocalisations. A survey in 2020 comprising visual line transect surveys and directional frequency analysis and recording (DIFAR) sonobuoy deployments resulted in 58 blue whale sightings from 2430 km of visual effort, including the photo-identification of 23 individual blue whales. Blue whale vocalisations were detected on all 31 sonobuoys deployed (114 h). In total, 41 blue whales were photo-identified from South Georgia between 2011 and 2020, none of which matched the 517 whales in the current Antarctic catalogue. These recent data suggest that blue whales have started to return to South Georgia waters, but continued visual and acoustic surveys are required to monitor any future changes in their distribution and abundance
The Transitional Stripped-Envelope SN 2008ax: Spectral Evolution and Evidence for Large Asphericity
Supernova (SN) 2008ax in NGC 4490 was discovered within hours after shock
breakout, presenting the rare opportunity to study a core-collapse SN beginning
with the initial envelope-cooling phase immediately following shock breakout.
We present an extensive sequence of optical and near-infrared spectra, as well
as three epochs of optical spectropolarimetry. Our initial spectra, taken two
days after shock breakout, are dominated by hydrogen Balmer lines at high
velocity. However, by maximum light, He I lines dominated the optical and
near-infrared spectra, which closely resembled those of normal Type Ib
supernovae (SNe Ib) such as SN 1999ex. This spectroscopic transition defines
Type IIb supernovae, but the strong similarity of SN 2008ax to normal SNe Ib
beginning near maximum light, including an absorption feature near 6270A due to
H-alpha at high velocities, suggests that many objects classified as SNe Ib in
the literature may have ejected similar amounts of hydrogen as SN 2008ax,
roughly a few x 0.01 M_sun. Early-time spectropolarimetry (6 and 9 days after
shock breakout) revealed strong line polarization modulations of 3.4% across
H-alpha, indicating the presence of large asphericities in the outer ejecta.
The continuum shares a common polarization angle with the hydrogen, helium, and
oxygen lines, while the calcium and iron absorptions are oriented at different
angles. This is clear evidence of deviations from axisymmetry even in the outer
ejecta. Intrinsic continuum polarization of 0.64% only nine days after shock
breakout shows that the outer layers of the ejecta were quite aspherical. A
single epoch of late-time spectropolarimetry, as well as the shapes of the
nebular line profiles, demonstrate that asphericities extended from the
outermost layers all the way down to the center of this SN. [Abridged]Comment: 24 pages, 21 figures, 4 tables, appendix, minor revisions to match
version accepted by Ap
The Identification of CELSR3 and Other Potential Cell Surface Targets in Neuroendocrine Prostate Cancer.
UNLABELLED
Although recent efforts have led to the development of highly effective androgen receptor (AR)-directed therapies for the treatment of advanced prostate cancer, a significant subset of patients will progress with resistant disease including AR-negative tumors that display neuroendocrine features [neuroendocrine prostate cancer (NEPC)]. On the basis of RNA sequencing (RNA-seq) data from a clinical cohort of tissue from benign prostate, locally advanced prostate cancer, metastatic castration-resistant prostate cancer and NEPC, we developed a multi-step bioinformatics pipeline to identify NEPC-specific, overexpressed gene transcripts that encode cell surface proteins. This included the identification of known NEPC surface protein CEACAM5 as well as other potentially targetable proteins (e.g., HMMR and CESLR3). We further showed that cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3) knockdown results in reduced NEPC tumor cell proliferation and migration in vitro. We provide in vivo data including laser capture microdissection followed by RNA-seq data supporting a causal role of CELSR3 in the development and/or maintenance of the phenotype associated with NEPC. Finally, we provide initial data that suggests CELSR3 is a target for T-cell redirection therapeutics. Further work is now needed to fully evaluate the utility of targeting CELSR3 with T-cell redirection or other similar therapeutics as a potential new strategy for patients with NEPC.
SIGNIFICANCE
The development of effective treatment for patients with NEPC remains an unmet clinical need. We have identified specific surface proteins, including CELSR3, that may serve as novel biomarkers or therapeutic targets for NEPC
Some Gender Implications of the âCivilising Missionâ of the Anglican Church for the Acholi Peoples of Northern Uganda
Anglican missionaries arriving in Ugandaâs Acholiland in 1903 saw the local peoples as in need not just of Christianisation but also of civilising. This last consisted primarily of inculcating western notions of gender identities for both men and women, with an emphasis on the wearing of gender-appropriate clothing and terminating the practices of polygyny and bride-price payment. The first missionaries considered the Acholi to have high levels of gender equality but they still believed conversion would improve womenâs status through domesticating them and instilling the notion of male superiority, despite the fact that local customary rituals did not distinguish on grounds of gender. Over decades, the population gradually converted to various Christian denominations, mainly Anglicanism and Catholicism, but without abandoning their customary rituals, using them as and when required, to ward off evil or ask for rain, for instance. The most significant impact of the civilising process was arguably the institutionalisation of the notion of masculine superiority now legitimised by appeals to what happened in the Garden of Eden. The paper is based on historical documents, both published and from the missionary archives, as well as on ethnographic research into gender in the region today
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