2,105 research outputs found
What are the communication skills and needs of doctors when communicating a poor prognosis to patients and their families? A qualitative study from South Africa
Background. Thousands of South Africans are diagnosed with life-threatening illness every year. Research shows that, globally, of the 20 million people who need palliative care at the end of life every year, <10% receive it.Objectives. To explore communication skills and practices of medical practitioners when conveying a poor prognosis to patients and families, and to identify their communication skills, needs and understanding of palliative care.Methods. This was an exploratory qualitative study of practising doctors, using a grounded theory approach. The study was conducted at a government-funded public hospital in Cape Town, South Africa, which is a referral centre for various illnesses, including cancer. Face-toface, one-on-one interviews using a semistructured interview guide were conducted, using audio recording.Results. The emerging theory from this study is that doctors who understand the principles of palliative care and who have an established working relationship with a palliative care team feel supported and express low levels of emotional anxiety when conveying a poor prognosis.Conclusion. Having hospital-based palliative care teams in all public hospitals will provide support for patients and doctors handling difficult conversations. All healthcare professionals should be trained in palliative care so that they can effectively communicate concerns related to poor prognosis with patients and their families. Communication, loss and grief issues should be part of the curriculum in all disciplines and throughout training in medical school
Cervical intra-epithelial neoplasia and invasive cervical cancer in black and white patients
The relative incidences of cervical intra-epithelial neoplasia (CIN) and invasive cervical cancer were studied in black and white patients at the academic hospitals of the University of the Orange Free State. A statistically highly significant difference was found between black and white patients, with a higher incidence of invasive cervical cancer than stage III CIN (CIN III) in black patients and a higher incidence of CIN III than invasive cervical cancer in white patients (P = 0,000092; 95% confidence interval -0,355 - -0,128). The time interval between the peak incidence of CIN III and that of invasive cervical cancer was found to be shorter in black than in white patients.These distressing findings emphasise the urgent need for a national cervical cytological screening programme to decrease the incidence of invasive cervical cancer. This serious yet preventable disease is still very prevalent in South Africa, especially among black women
Aquilegia, Vol. 23 No. 2, March-April 1999: Newsletter of the Colorado Native Plant Society
https://epublications.regis.edu/aquilegia/1089/thumbnail.jp
Complete homochirality induced by the nonlinear autocatalysis and recycling
A nonlinear autocatalysis of a chiral substance is shown to achieve
homochirality in a closed system, if the back-reaction is included. Asymmetry
in the concentration of two enantiomers or the enantiometric excess increases
due to the nonlinear autocatalysis. Furthermore, when the back-reaction is
taken into account, the reactant supplied by the decomposition of the
enantiomers is recycled to produce more and more the dominant one, and
eventually the homochirality is established.Comment: 4 pages, 2 figure
Revisiting the origin of the high metallicities of sub-damped Lyman-alpha systems
Sub-damped Lyman-alpha systems (sub-DLAs) have previously been found to
exhibit a steeper metallicity evolution than the classical damped Lyman-alpha
systems (DLAs), evolving to close to solar metallicity by z~1. From new
high-resolution spectra of 17 sub-DLAs we have increased the number of
measurements of [Fe/H] at z<1.7 by 25% and compiled the most complete
literature sample of sub-DLA and DLA abundances to date. We find that sub-DLAs
are indeed significantly more metal-rich than DLAs, but only at z<1.7; the
metallicity distributions of sub-DLAs and DLAs at z>1.7 are statistically
consistent. We also present the first evidence that sub-DLAs follow a velocity
width-metallicity correlation over the same velocity range as DLAs, but the
relation is offset to higher metallicities than the DLA relation. On the basis
of these results, we revisit the previous explanation that the systematically
higher metallicities observed in sub-DLAs are indicative of higher host galaxy
masses. We discuss the various problems that this interpretation encounters and
conclude that in general sub-DLAs are not uniquely synonymous with massive
galaxies. We rule out physically related sources of bias (dust, environment,
ionization effects) and examine systematics associated with the selection and
analysis of low-redshift sub-DLAs. We propose that the high metallicities of
sub-DLAs at z<1.7 that drives an apparently steep evolution may be due to the
selection of most low-redshift sub-DLAs based on their high MgII equivalent
widths.Comment: 6 pages, 3 figures, MNRAS, in pres
What are the communication skills and needs of doctors when communicating a poor prognosis to patients and their families? A qualitative study from South Africa
Background. Thousands of South Africans are diagnosed with life-threatening illness every year. Research shows that, globally, of the 20 million people who need palliative care at the end of life every year, <10% receive it.Objectives. To explore communication skills and practices of medical practitioners when conveying a poor prognosis to patients and families, and to identify their communication skills, needs and understanding of palliative care.Methods. This was an exploratory qualitative study of practising doctors, using a grounded theory approach. The study was conducted at a government-funded public hospital in Cape Town, South Africa, which is a referral centre for various illnesses including cancer. Face-to-face, one-on-one interviews using a semistructured interview guide were conducted, using audio recording.Results. The emerging theory from this study is that doctors who understand the principles of palliative care and who have an established working relationship with a palliative care team feel supported and express low levels of emotional anxiety when conveying a poor prognosis.Conclusion. Having hospital-based palliative care teams in all public hospitals will provide support for patients and doctors handling difficult conversations. All healthcare professionals should be trained in palliative care so as to effectively communicate with patients and their families concerns related to poor prognosis. Communication, loss and grief issues should be part of the curriculum in all disciplines and throughout training in medical school
The Role of Sub-damped Lyman-alpha Absorbers in the Cosmic Evolution of Metals
Observations of low mean metallicity of damped Lyman-alpha (DLA) quasar
absorbers at all redshifts studied appear to contradict the predictions for the
global mean interstellar metallicity in galaxies from cosmic chemical evolution
models. On the other hand, a number of metal-rich sub-DLA systems have been
identified recently, and the fraction of metal-rich sub-DLAs appears to be
considerably larger than that of metal-rich DLAs, especially at z < 1.5. In
view of this, here we investigate the evolution of metallicity in sub-DLAs. We
find that the mean Zn metallicity of the observed sub-DLAs may be higher than
that of the observed DLAs, especially at low redshifts, reaching a near-solar
level at z <~ 1. This trend does not appear to be an artifact of sample
selection, the use of Zn, the use of N_{HI}-weighting, or observational
sensitivity. While a bias against very low metallicity could be present in the
sub-DLA sample in some situations, this cannot explain the difference between
the DLA and sub-DLA metallicities at low z. The primary reason for the
difference between the DLAs and sub-DLAs appears to be the dearth of metal-rich
DLAs. We estimate the sub-DLA contribution to the total metal budget using
measures of their metallicity and comoving gas density. These calculations
suggest that at z <~ 1, the contribution of sub-DLAs to the total metal budget
may be several times that of DLAs. At higher redshifts also, there are
indications that the sub-DLAs may contribute significantly to the cosmic metal
budget.Comment: 9 pages, 2 figures, Accepted for Publication in the Astrophysical
Journa
Super-Solar Metallicity in Weak Mg II Absorption Systems at z ~ 1.7
Through photoionization modeling, constraints on the physical conditions of
three z ~ 1.7 single-cloud weak Mg II systems (W_r(2796) < 0.3A) are derived.
Constraints are provided by high resolution R = 45,000, high signal-to-noise
spectra of the three quasars HE0141-3932, HE0429-4091, and HE2243-6031 which we
have obtained from the ESO archive of VLT/UVES. Results are as follows:
(1) The single-cloud weak Mg II absorption in the three z ~ 1.7 systems is
produced by clouds with ionization parameters of -3.8 < logU < -2.0 and sizes
of 1-100 pc.
(2) In addition to the low-ionization phase Mg II clouds, all systems need an
additional 1-3 high-ionization phase C IV clouds within 100 km/s of the Mg II
component. The ionization parameters of the C IV phases range from -1.9 < logU
< -1.0, with sizes of tens of parsecs to kiloparsecs.
(3) Two of the three single-cloud weak Mg II absorbers have near-solar or
super-solar metallicities, if we assume a solar abundance pattern. Although
such large metallicities have been found for z < 1 weak Mg II absorbers, these
are the first high metallicities derived for such systems at higher redshifts.
(4) Two of the three weak Mg II systems also need additional low-metallicity,
broad Lya absorption lines, offset in velocity from the metal-line absorption,
in order to reproduce the full Lya profile.
(5) Metallicity in single-cloud weak Mg II systems are more than an order of
magnitude larger than those in Damped Lya systems at z ~ 1.7. In fact, there
appears to be a gradual decrease in metallicity with increasing N(HI), from
these, the most metal-rich Lya forest clouds, to Lyman limit systems, to
sub-DLAs, and finally to the DLAs.Comment: 25 pages, 7 figures, accepted by the Astrophysical Journa
Metal-rich absorbers at high redshifts: abundance patterns
(Abbreviated) From six spectra of high-z QSOs, we select eleven metal-rich,
Z>=Z_solar, and optically-thin to the ionizing radiation, N(HI)<10^17 cm^-2,
absorption systems ranging between z=1.5 and z=2.9 and revealing lines of
different ions in subsequent ionization stages. The majority of the systems (10
from 11) show abundance patterns which relate them to outflows from low and
intermediate mass stars. All systems have sub-kpc linear sizes along the
line-of-sight with many less than 20 pc. In several systems, silicon is
deficient, presumably due to the depletion onto dust grains in the envelopes of
dust-forming stars and the subsequent gas-dust separation. At any value of
[C/H], nitrogen can be either deficient, [N/C]0, which
supposes that the nitrogen enrichment occurs irregularly. In some cases, the
lines of MgII 2796, 2803 appear to be shifted, probably as a result of an
enhanced content of heavy isotopes 25Mg and 26Mg in the absorbing gas relative
to the solar isotopic composition. Seven absorbers are characterized by low
mean ionization parameter U, log U<-2.3, among them only one system has a
redshift z>2 whereas all others are found at z ~= 1.8. Comparing the space
number density of metal-rich absorbers with the comoving density of
star-forming galaxies at z ~= 2, we estimate that the circumgalactic volume of
each galaxy is populated by 10^7 - 10^8 such absorbers with total mass
<=1/100th of the stellar galactic mass. Possible effects of high metal content
on the peak values of star-forming and AGN activities at z~2 are discussed.Comment: 19 pages, 16 figures, 3 tables. Accepted for publication in A&
- …