2,423 research outputs found
Routine surveillance data on AIDS and HIV infections in the UK: a description of the data available and their use for short-term planning
In the UK surveillance of AIDS and HIV infection is based on routine reporting systems. Whilst attempts are made to ensure that AIDS data are as complete as possible, numbers of reports fluctuate from month to month for reasons which are described. In 1986 there was an increase in death certificates naming AIDS as a cause of death in patients who were not identifiable in the surveillance data. More active surveillance is now undertaken in order to minimize this and other possible discrepancies. It is probable that most cases of AIDS are reported and therefore these data can be used to describe trends in the epidemic by 'risk group'. Laboratory reports of HIV antibody-positive tests could give an earlier indication of trends because of the long incubation period of AIDS. But these laboratory data are difficult to interpret because they represent an incomplete and biased sample of all positive persons. AIDS cases are still being reported at a rate which is increasing approximately exponentially. Short-term predictions are presented showing a growth in the epidemic which is consistent with previously published predictions. Most cases are in the homosexual risk group. New asymptomatic homosexual patients with HIV antibody are still being identified. The epidemic of AIDS in haemophilia patients should be of finite size although new cases of AIDS are likely to continue to be diagnosed for several years. AIDS due to blood transfusion given in the UK before donor screening appears to be a much smaller epidemic. The epidemic in drug abusers is increasing. Heterosexually acquired AIDS and HIV infections are being reported in small but increasing numbers
Multiple communication mechanisms between sensor kinases are crucial for virulence in Pseudomonas aeruginosa
This is the author accepted manuscript. The final version is available as an open access article from the publisher via the DOI in this recordBacteria and many non-metazoan Eukaryotes respond to stresses and threats using two-component systems (TCSs) comprising sensor kinases (SKs) and response regulators (RRs). Multikinase networks, where multiple SKs work together, detect and integrate different signals to control important lifestyle decisions such as sporulation and virulence. Here, we study interactions between two SKs from Pseudomonas aeruginosa, GacS and RetS, which control the switch between acute and chronic virulence. We demonstrate three mechanisms by which RetS attenuates GacS signalling: RetS takes phosphoryl groups from GacS-P; RetS has transmitter phosphatase activity against the receiver domain of GacS-P; and RetS inhibits GacS autophosphorylation. These mechanisms play important roles in vivo and during infection, and exemplify an unprecedented degree of signal processing by SKs that may be exploited in other multikinase networks.This work was supported by the Medical Research Council (MRC) (grant number MR/
M020045/1), the Leverhulme Trust (grant number RPG-2014-228), the RoseTrees Trust
(grant number M328) and a NERC PhD studentship (grant number 1076449)
Emergence of robust 2D skyrmions in SrRuO3 ultrathin film without the capping layer
Magnetic skyrmions have fast evolved from a novelty, as a realization of
topologically protected structure with particle-like character, into a
promising platform for new types of magnetic storage. Significant engineering
progress was achieved with the synthesis of compounds hosting room-temperature
skyrmions in magnetic heterostructures, with the interfacial
Dzyaloshinskii-Moriya interactions (DMI) conducive to the skyrmion formation.
Here we report findings of ultrathin skyrmion formation in a few layers of
SrRuO3 grown on SrTiO3 substrate without the heavy-metal capping layer.
Measurement of the topological Hall effect (THE) reveals a robust stability of
skyrmions in this platform, judging from the high value of the critical field
1.57 Tesla (T) at low temperature. THE survives as the field is tilted by as
much as 85 degrees at 10 Kelvin, with the in-plane magnetic field reaching up
to 6.5 T. Coherent Bragg Rod Analysis, or COBRA for short, on the same film
proves the rumpling of the Ru-O plane to be the source of inversion symmetry
breaking and DMI. First-principles calculations based on the structure obtained
from COBRA find significant magnetic anisotropy in the SrRuO3 film to be the
main source of skyrmion robustness. These features promise a few-layer SRO to
be an important new platform for skyrmionics, without the necessity of
introducing the capping layer to boost the spin-orbit coupling strength
artificially.Comment: Supplementary Information available upon reques
Emergence of robust 2D skyrmions in SrRuO3 ultrathin film without the capping layer
Magnetic skyrmions have fast evolved from a novelty, as a realization of
topologically protected structure with particle-like character, into a
promising platform for new types of magnetic storage. Significant engineering
progress was achieved with the synthesis of compounds hosting room-temperature
skyrmions in magnetic heterostructures, with the interfacial
Dzyaloshinskii-Moriya interactions (DMI) conducive to the skyrmion formation.
Here we report findings of ultrathin skyrmion formation in a few layers of
SrRuO3 grown on SrTiO3 substrate without the heavy-metal capping layer.
Measurement of the topological Hall effect (THE) reveals a robust stability of
skyrmions in this platform, judging from the high value of the critical field
1.57 Tesla (T) at low temperature. THE survives as the field is tilted by as
much as 85 degrees at 10 Kelvin, with the in-plane magnetic field reaching up
to 6.5 T. Coherent Bragg Rod Analysis, or COBRA for short, on the same film
proves the rumpling of the Ru-O plane to be the source of inversion symmetry
breaking and DMI. First-principles calculations based on the structure obtained
from COBRA find significant magnetic anisotropy in the SrRuO3 film to be the
main source of skyrmion robustness. These features promise a few-layer SRO to
be an important new platform for skyrmionics, without the necessity of
introducing the capping layer to boost the spin-orbit coupling strength
artificially.Comment: Supplementary Information available upon reques
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Thermodynamics of Cr2O3, FeCr2O4, ZnCr2O4 and CoCr2O4
High temperature heat capacity measurements were obtained for Cr{sub 2}O{sub 3}, FeCr{sub 2}O{sub 4}, ZnCr{sub 2}O{sub 4} and CoCr{sub 2}O{sub 4} using a differential scanning calorimeter. These data were combined with previously-available, overlapping heat capacity data at temperatures up to 400 K and fitted to 5-parameter Maier-Kelley C{sub p}(T) equations. Expressions for molar entropy were then derived by suitable integration of the Maier-Kelley equations in combination with recent S{sup o}(298) evaluations. Finally, a database of high temperature equilibrium measurements on the formation of these oxides was constructed and critically evaluated. Gibbs energies of Cr{sub 2}O{sub 3}, FeCr{sub 2}O{sub 4} and CoCr{sub 2}O{sub 4} were referenced by averaging the most reliable results at reference temperatures of 1100, 1400 and 1373 K, respectively, while Gibbs energies for ZnCr{sub 2}O{sub 4} were referenced to the results of Jacob [Thermochim. Acta 15 (1976) 79-87] at 1100 K. Thermodynamic extrapolations from the high temperature reference points to 298.15 K by application of the heat capacity correlations gave {Delta}{sub f}G{sup o}(298) = -1049.96, -1339.40, -1428.35 and -1326.75 kJ mol{sup -1} for Cr{sub 2}O{sub 3}, FeCr{sub 2}O{sub 4}, ZnCr{sub 2}O{sub 4} and CoCr{sub 2}O{sub 4}, respectively
Specific orofacial problems experienced by musicians
Background: Patients who play musical instruments (especially wind and stringed instruments) and vocalists are prone to particular types of orofacial problems. Some problems are caused by playing and some are the result of dental treatment. This paper proposes to give an insight into these problems and practical guidance to general practice dentists. Method: Information in this paper is gathered from studies published in dental, music and occupational health journals, and from discussions with career musicians and music teachers. Results: Orthodontic problems, soft tissue trauma, focal dystonia, denture retention, herpes labialis, dry mouth and temporomandibular joint (TMJ) disorders were identified as orofacial problems of career musicians. Options available for prevention and palliative treatment as well as instrument selection are suggested to overcome these problems. Conclusions: Career musicians express reluctance to attend dentists who are not sensitive to their specific needs. General practitioner dentists who understand how the instruments impact on the orofacial structures and are aware of potential problems faced by musicians are able to offer preventive advice and supportive treatment to these patients, especially those in the early stages of their career
Competing biosecurity and risk rationalities in the Chittagong poultry commodity chain, Bangladesh
This paper anthropologically explores how key actors in the Chittagong live bird trading network perceive biosecurity and risk in relation to avian influenza between production sites, market maker scenes and outlets. They pay attention to the past and the present, rather than the future, downplaying the need for strict risk management, as outbreaks have not been reported frequently for a number of years. This is analysed as ‘temporalities of risk perception regarding biosecurity’, through Black Swan theory, the idea that unexpected events with major effects are often inappropriately rationalized (Taleb in The Black Swan. The impact of the highly improbable, Random House, New York, 2007). This incorporates a sociocultural perspective on risk, emphasizing the contexts in which risk is understood, lived, embodied and experienced. Their risk calculation is explained in terms of social consent, practical intelligibility and convergence of constraints and motivation. The pragmatic and practical orientation towards risk stands in contrast to how risk is calculated in the avian influenza preparedness paradigm. It is argued that disease risk on the ground has become a normalized part of everyday business, as implied in Black Swan theory. Risk which is calculated retrospectively is unlikely to encourage investment in biosecurity and, thereby, points to the danger of unpredictable outlier events
Beyond viral suppression of HIV – the new quality of life frontier
BACKGROUND: In 2016, the World Health Organization (WHO) adopted a new Global Health Sector Strategy on HIV for 2016–2021. It establishes 15 ambitious targets, including the ‘90-90-90’ target calling on health systems to reduce under-diagnosis of HIV, treat a greater number of those diagnosed, and ensure that those being treated achieve viral suppression. DISCUSSION: The WHO strategy calls for person-centered chronic care for people living with HIV (PLHIV), implicitly acknowledging that viral suppression is not the ultimate goal of treatment. However, it stops short of providing an explicit target for health-related quality of life. It thus fails to take into account the needs of PLHIV who have achieved viral suppression but still must contend with other intense challenges such as serious non-communicable diseases, depression, anxiety, financial stress, and experiences of or apprehension about HIV-related discrimination. We propose adding a ‘fourth 90’ to the testing and treatment target: ensure that 90 % of people with viral load suppression have good health-related quality of life. The new target would expand the continuum-of-services paradigm beyond the existing endpoint of viral suppression. Good health-related quality of life for PLHIV entails attention to two domains: comorbidities and self-perceived quality of life. CONCLUSIONS: Health systems everywhere need to become more integrated and more people-centered to successfully meet the needs of virally suppressed PLHIV. By doing so, these systems can better meet the needs of all of their constituents – regardless of HIV status – in an era when many populations worldwide are living much longer with multiple comorbidities
Consensus clustering in complex networks
The community structure of complex networks reveals both their organization
and hidden relationships among their constituents. Most community detection
methods currently available are not deterministic, and their results typically
depend on the specific random seeds, initial conditions and tie-break rules
adopted for their execution. Consensus clustering is used in data analysis to
generate stable results out of a set of partitions delivered by stochastic
methods. Here we show that consensus clustering can be combined with any
existing method in a self-consistent way, enhancing considerably both the
stability and the accuracy of the resulting partitions. This framework is also
particularly suitable to monitor the evolution of community structure in
temporal networks. An application of consensus clustering to a large citation
network of physics papers demonstrates its capability to keep track of the
birth, death and diversification of topics.Comment: 11 pages, 12 figures. Published in Scientific Report
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