13,345 research outputs found
Spatial clusters of gonorrhoea in England with particular reference to the outcome of partner notification: 2012 and 2013
Background: This study explored spatial-temporal variation in diagnoses of gonorrhoea to identify and quantify endemic areas and clusters in relation to patient characteristics and outcomes of partner notification (PN) across England, UK. Methods: Endemic areas and clusters were identified using a two-stage analysis with Kulldorff’s scan statistics (SaTScan). Results Of 2,571,838 tests, 53,547 diagnoses were gonorrhoea positive (positivity = 2.08%). The proportion of diagnoses in heterosexual males was 1.5 times that in heterosexual females. Among index cases, men who have sex with men (MSM) were 8 times more likely to be diagnosed with gonorrhoea than heterosexual males (p<0.0001). After controlling for age, gender, ethnicity and deprivation rank, 4 endemic areas were identified including 11,047 diagnoses, 86% of which occurred in London. 33 clusters included 17,629 diagnoses (34% of total diagnoses in 2012 and 2013) and spanned 21 locations, some of which were dominated by heterosexually acquired infection, whilst others were MSM focused. Of the 53,547 diagnoses, 14.5% (7,775) were the result of PN. The proportion of patients who attended services as a result of PN varied from 0% to 61% within different age, gender and sexual orientation cohorts. A third of tests resulting from PN were positive for gonorrhoea. 25% of Local Authorities (n = 81, 95% CI: 20.2, 29.5) had a higher than expected proportion for female PN diagnoses as compared to 16% for males (n = 52, 95% CI: 12.0, 19.9). Conclusions: The English gonorrhoea epidemic is characterised by spatial-temporal variation. PN success varied between endemic areas and clusters. Greater emphasis should be placed on the role of PN in the control of gonorrhoea to reduce the risk of onward transmission, re-infection, and complications of infection
Adaptive weight estimator for quantum error correction
Quantum error correction of a surface code or repetition code requires the
pairwise matching of error events in a space-time graph of qubit measurements,
such that the total weight of the matching is minimized. The input weights
follow from a physical model of the error processes that affect the qubits.
This approach becomes problematic if the system has sources of error that
change over time. Here we show how the weights can be determined from the
measured data in the absence of an error model. The resulting adaptive decoder
performs well in a time-dependent environment, provided that the characteristic
time scale of the variations is greater than , with the duration of one error-correction cycle and
the typical error probability per qubit in one cycle.Comment: 5 pages, 4 figure
Twisted Fermi surface of a thin-film Weyl semimetal
The Fermi surface of a conventional two-dimensional electron gas is
equivalent to a circle, up to smooth deformations that preserve the orientation
of the equi-energy contour. Here we show that a Weyl semimetal confined to a
thin film with an in-plane magnetization and broken spatial inversion symmetry
can have a topologically distinct Fermi surface that is twisted into a
\mbox{figure-8} opposite orientations are coupled at a crossing which is
protected up to an exponentially small gap. The twisted spectral response to a
perpendicular magnetic field is distinct from that of a deformed Fermi
circle, because the two lobes of a \mbox{figure-8} cyclotron orbit give
opposite contributions to the Aharonov-Bohm phase. The magnetic edge channels
come in two counterpropagating types, a wide channel of width and a narrow channel of width (with
the magnetic length and the momentum separation
of the Weyl points). Only one of the two is transmitted into a metallic
contact, providing unique magnetotransport signatures.Comment: V4: 10 pages, 14 figures. Added figure and discussion about
"uncrossing deformations" of oriented contours, plus minor corrections.
Published in NJ
“I wish I’d told them”: a qualitative study examining the unmet psychosexual needs of prostate cancer patients during follow-up after treatment
<b>Objective</b> To gain insight into patients' experiences of follow-up care after treatment for prostate cancer and identify unmet psychosexual needs.<p></p>
<b>Methods</b> Semi-structured interviews were conducted with a purposive sample of 35 patients aged 59-82 from three UK regions. Partners were included in 18 interviews. Data were analyzed using constant comparison. <p></p>
<b>Results</b> (1) Psychosexual problems gained importance over time, (2) men felt they were rarely invited to discuss psychosexual side effects within follow-up appointments and lack of rapport with health care professionals made it difficult to raise problems themselves, (3) problems were sometimes concealed or accepted and professionals' attempts to explore potential difficulties were resisted by some, and (4) older patients were too embarrassed to raise psychosexual concerns as they felt they would be considered 'too old' to be worried about the loss of sexual function.<p></p>
<b>Conclusion</b> Men with prostate cancer, even the very elderly, have psychosexual issues for variable times after diagnosis. These are not currently always addressed at the appropriate time for the patient.Practice implications Assessments of psychosexual problems should take place throughout the follow-up period, and not only at the time of initial treatment. Further research examining greater willingness or reluctance to engage with psychosexual interventions may be particularly helpful in designing future intervention
Guidelines for the management of chronic obstructive pulmonary disease : Working group of the South African pulmonology society
Objective: This guideline has been developed in order to optimise the management of patients with chronic obstructive pulmonary disease (COPD) at all levels health care systems in South Africa. It contains an action plan for early recognition and appropriate treatment of this common condition.Options: Treatment regimens are recommended for patients with mild (stage I), and severe (stage III) disease.Outcomes: Optimal management of patients with COPD may achieve a reduction in breathlessness, improved quality of life, prevention of complications and limitation of disease progression.Evidence: The working Group comprised mainly pulmonologists, but included an anaesthetist, a pharmacologist and physiotherapist. Detailed literature review with particular attention to similar guideline documents from Europe and the USA was performed before the meeting.Recommendations: Steps in the management of patients with COPD include early recognition of the disease, smoking cessation, treatment of airflow obstruction with appropriate drugs (singly or in combination), education and pulmonary rehabilitation, and limitation of disease progression and complications. Detailed recommendations are made with regard to the use and interpretation of a trial of oral corticosteroid therapy. Indications for hospitalisation, intensive care unit admission and ventilatory support are provided.Validation: This guideline is similar to those recommended by other groups outside South Africa. It was developed by a working group of the South Africa Pulmonology Society and is endorsed by the Medical Association of South Africa.Sponsors: The meeting of the Working Group was sponsored by Boehringer Ingelheim. This sponsorship did not influence the activities of the Group
It's a wonderful tail: the mass loss history of Mira
Recent observations of the Mira AB binary system have revealed a surrounding
arc-like structure and a stream of material stretching 2 degrees away in
opposition to the arc. The alignment of the proper motion vector and the
arc-like structure shows the structures to be a bow shock and accompanying
tail. We have successfully hydrodynamically modelled the bow shock and tail as
the interaction between the asymptotic giant branch (AGB) wind launched from
Mira A and the surrounding interstellar medium. Our simulations show that the
wake behind the bow shock is turbulent: this forms periodic density variations
in the tail similar to those observed. We investigate the possiblity of
mass-loss variations, but find that these have limited effect on the tail
structure. The tail is estimated to be approximately 450,000 years old, and is
moving with a velocity close to that of Mira itself. We suggest that the
duration of the high mass-loss phase on the AGB may have been underestimated.
Finally, both the tail curvature and the rebrightening at large distance can be
qualitatively understood if Mira recently entered the Local Bubble. This is
estimated to have occured 17 pc downstream from its current location.Comment: 12 pages, 3 colour figures, accepted by ApJ Part II (Letters
An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines
We present graphically the results of several thousand photoionization
calculations of broad emission line clouds in quasars, spanning seven orders of
magnitude in hydrogen ionizing flux and particle density. The equivalent widths
of 42 quasar emission lines are presented as contours in the particle density -
ionizing flux plane for a typical incident continuum shape, solar chemical
abundances, and cloud column density of . Results are
similarly given for a small subset of emission lines for two other column
densities ( and ), five other incident
continuum shapes, and a gas metallicity of 5 \Zsun. These graphs should prove
useful in the analysis of quasar emission line data and in the detailed
modeling of quasar broad emission line regions. The digital results of these
emission line grids and many more are available over the Internet.Comment: 16 pages, LaTeX (AASTeX aaspp4.sty); to appear in the 1997 ApJS: full
contents of the 9 photoionization grids presented in this paper may be found
at http://www.pa.uky.edu/~korista/grids/grids.htm
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