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In 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.
The observations of the supernova remnant G343.1—2.3 with the Mauritius Radio Telescope, the Australia Compact Array, and the Hobart Single dish are presented. With these more sensitive measurements the association with the pulsar PSR1706-44 becomes much more likely. The major points from the observations are presented.
Stars are tidally disrupted and accreted when they approach massive black holes (MBHs) closely, producing a flare of electromagnetic radiation. The majority of the (approximately two dozen) tidal disruption events (TDEs) identified so far have been discovered by their luminous, transient X-ray emission. Once TDEs are detected in much larger numbers, in future dedicated transient surveys, a wealth of new applications will become possible. Here, we present the proposed Einstein Probe mission, which is a dedicated time-domain soft X-ray all-sky monitor aiming at detecting X-ray transients including TDEs in large numbers. The mission consists of a wide-field micro-pore Lobster-eye imager (60° × 60°), and is designed to carry out an all-sky transient survey at energies of 0.5-4 keV. It will also carry a more sensitive telescope for X-ray follow-ups, and will be capable of issuing public transient alerts rapidly. Einstein Probe is expected to revolutionise the field of TDE research by detecting several tens to hundreds of events per year from the early phase of flares, many with long-term, well sampled lightcurves.
The objective of this study was to assess the prevalence of Ureaplasma urealyticum and Mycoplasma hominis infections and to investigate associations between their presence in the lower female genital tract and lifestyle characteristics. The study was performed on a population of 3115 women, comparing the demographic and behavioural characteristics of 872 women with U. urealyticum infection and 142 women with M. hominis with uninfected women, using univariate and multiple logistic regression analysis. The prevalence of infection with U. urealyticum was 28% and M. hominis was 4·6%. In multivariate logistic regression analysis, intrauterine device, number of sexual partners and age (<35 years) were significantly associated with U. urealyticum while previous induced abortion, condom use and young age at first intercourse (<16 years) were associated with M. hominis infection. U. urealyticum infection presents the same demographic and behavioural characteristics of a sexually transmitted disease. The unprotective role of condom use suggests a non-sexual mode of transmission of M. hominis infection.
Standard acute psychiatric care in the UK is costly but problematic. Alternatives to standard in-patient wards exist, but little is known about their effectiveness, implementation and sustainability. This paper explores successful features and limitations of five residential alternative services in England and factors that facilitate or impede their initial and sustained implementation and success.
Semi-structured interviews about the functioning of six alternative services were conducted with 36 mental health professionals with good working knowledge of, and various connections with these services. A group interview with study researchers was also conducted. Data were analysed using thematic analysis.
One service did not show evidence of operating as an alternative and was excluded from further analysis. The remaining five alternatives are valued for providing a more holistic style of care than standard services that confers many perceived benefits. However, they are seen as less appropriate for compulsorily detained or highly disturbed patients, and as providing less comprehensive treatment packages than hospital settings. Factors identified as important to successful implementation and sustainability are: responding to known shortcomings in local acute care systems; balancing role clarity and adaptability; integration with other services; and awareness of the alternative among relevant local health-care providers.
Residential alternatives can play an important role in managing mental health crises. Their successful implementation and endurance depend on establishing and maintaining a valued position within local service systems. Findings contribute to bridging the gap between research evidence on the problems of standard acute care and delivering improved crisis management services.
The resistivity of the as-fabricated thermistor material, nickel-iron-manganite, changes during initial aging in the temperature range of 150-300ºC before becoming stable.X-ray photoelectron spectroscopy (XPS) was used to determine if any valency change or chemical shift of the cations or oxygen occurred during aging. The goal of the study was to identify any ionic changes that might affect thermistor stability. The only observed changes in 2p3/2 peaks due to aging were those related to Ni ions; the same peaks for Mn, Fe, and the 0-Is peak were unchanged. The changes in the Ni 2p3/2 peak may possibly be related to: (a) the migration of Ni2+ ions from octahedral to tetrahedral sites, (b) subtle changes in the energy states of Ni2+ which promoted a more stable ionic structure, or (c) the presence of Ni3+ ions, some of which revert to Ni2s+.
Hydrogenated amorphous silicon containing chlorine (a-Si:H (Cl)) films have been grown by plasma enhanced chemical vapor deposition from a mixture of silane and dichlorosilane with a dichlorosilane concentration up to 60%. We report on the film properties in the as-deposited state and the behavior of the films under both high intensity pulsed laser illumination and long-term AMI illumination. With increasing dichlorosilane concentration the films show an increased resilience to the creation of light induced defects, as determined from the constant photocurrent method. After 900 hours under AMI illumination, the defect density shows a minimum (< 1016 cnr−3) for a 10 % mixing ratio.
Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have all been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of corplex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects — and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.
Differences in the content of care provided by acute in-patient mental health wards and residential crisis services such as crisis houses have not been researched.
To compare planned and actual care provided at alternative and standard acute wards and to investigate the relationship between care received and patient satisfaction.
Perspectives of stakeholders, including local service managers, clinicians and commissioners, were obtained from 23 qualitative interviews. Quantitative investigation of the care provided at four alternative and four standard services was undertaken using three instruments developed for this study. The relationship of care received to patient satisfaction was explored.
No significant difference was found in intensity of staff– patient contact between alternative and standard services. Alternative services provided more psychological and less physical and pharmacological care than standard wards. Care provision may be more collaborative and informal in alternative services. All measured types of care were positively associated with patient satisfaction. Measured differences in the care provided did not explain the greater acceptability of community alternatives.
Similarities in care may be more marked than differences at alternative and standard services. Staff–patient contact is an important determinant of patient satisfaction, so increasing it should be a priority for all acute in-patient services.
Key questions regarding residential alternatives to standard acute psychiatric care, such as crisis houses and short-stay in-patient units, concern the role that they fulfil within local acute care systems, and whether they manage people with needs and illnesses of comparable severity to those admitted to standard acute wards.
To study the extent to which people admitted to residential alternatives and to standard acute services are similar, and the role within local acute care systems of admission to an alternative service.
Our approach combined quantitative and qualitative methods. Consecutive cohorts of patients in six residential alternatives across England and six standard acute wards in the same areas were identified, and clinical and demographic characteristics, severity of symptoms, impairments and risks compared. Semi-structured interviews with key stakeholders in each local service system were used to explore the role and functioning of each alternative.
Being already known to services (OR = 2.6, 95% CI 1.3–5.2), posing a lower risk to others (OR = 0.49, 95% CI 0.31–0.78) and having initiated help-seeking in the current crisis (OR = 2.2, 95% CI 1.2–4.3) were associated with being admitted to an alternative rather than a standard service. Stakeholder interviews suggested that alternatives have a role that is similar but not identical to standard hospital services. They can divert some, but not all, patients from acute admission.
Residential alternatives are integrated into catchment area mental health systems. They serve similar, but not identical, clinical populations to standard acute wards and provide some, but not all, of the functions of these wards.
Reducing greenhouse gas emissions and optimizing energy consumption are important for mitigating climate change and improving resource use efficiency. Strawberry (Fragaria xananassa Duch) crops are a key component of the UK soft fruit sector and potentially resource-intensive crops. This is the first study to undertake a detailed environmental impact assessment of all methods of UK strawberry production. A total of 14 systems with six additional sub-systems grown for between 1 and 3 years were identified. They were defined by the growing of short-day (Junebearer) or everbearer varieties, organic production, covering with polytunnels or grown in the open, soil-grown (with or without fumigation) or container-grown (with peat or coir substrate) and summer or spring planted. Pre-harvest, the global warming potential varied between 1·5 and 10·3 t CO2 equiv/ha/crop or 0·13 and 1·14 t CO2 equiv/t of class 1 fruit. Key factors included the use of tunnels, mulch and irrigation, sterilization of soil with fumigants and the use of peat substrate. Seasonal crops without covers grown where rotation of sufficient length reduced Verticillium (system 4) were the most efficient. System 4a (that did not use mulch) emitted 0·13 t CO2 equiv/t of class 1 fruit. A second or third cropping year in soil-grown systems prolonged the effect of mulch and soil fumigants. Greenhouse gases from system 4 (with mulch) averaged 0·30 t CO2 equiv/t of class 1 fruit after 3 years of cropping compared to 0·63 and 0·36 t CO2 equiv/t after 1 and 2 years, respectively.
The ESEN (European Sero-Epidemiology Network) project was established to harmonize the
seroepidemiology of five vaccine preventable infections including measles, mumps and rubella
in eight European countries. This involved achieving comparability both in the assay results
from testing in different centres and also sampling methodology. Standardization of enzyme
immunoassay results was achieved through the development of common panels of sera by
designated reference centres. The panels were tested at the reference laboratory and then
distributed to each participating laboratory for testing using their routine methods.
Standardization equations were calculated by regressing the quantitative results against those of
the reference laboratory. Our study found large differences in unitage between participants,
despite all using an EIA method standardized against an international or local standard.
Moreover, our methodology adjusted for this difference. These standardization equations will
be used to convert the results of main serosurvey testing into the reference country unitage to
ensure inter-country comparability.
Cost effectiveness analyses of alternative hepatitis B vaccination
programmes in England and
Wales require a robust estimate of the lifetime risk of carriage. To this
end, we report the
prevalence of infection in 3781 anonymized individuals aged 15–44
years whose sera were
submitted in 1996 to 16 microbiology laboratories in England and Wales.
One hundred and
forty-six individuals (3·9%) were confirmed as anti HBc positive,
including 14 chronic carriers
(0·37%). The prevalence of infection and carriage was higher in
samples collected in London
and increased with age. No increased risk of infection was seen in sera
(GUM) clinics. Only 15 sera positive for hepatitis B were also positive
for hepatitis C. Our
results confirm the low prevalence of hepatitis B in England and Wales,
are consistent with
previous estimates of carriage and suggest that many infections were acquired
outside the UK. Future prevalence studies should determine the country
of birth and other risk
factors for each individual in order to confirm these findings.
The aim of the study was to determine whether memantine
could slow down the changes seen in the rabbit and rat
retina following ischemia/reperfusion. A “suction
cup procedure,” which raises the intraocular pressure,
was used to give an ischemic insult to the rabbit retina.
The electroretinogram was recorded before ischemia and
after 2 days of reperfusion. Memantine or saline (10 μl)
was injected into the eye before ischemia. Immunohistochemistry
was used to study the effect of ischemia/reperfusion on
the GABA, ChAT, and αPKC immunoreactivities. Ischemia/reperfusion
injury to the rat retina was induced by raising the intraocular
pressure above the systolic blood pressure for 60 min,
followed by reperfusion of 3–14 days. Memantine (5
mg/kg) or saline was injected i.p. at the onset of ischemia
or reperfusion. Immunohistochemistry was used to study
the effect of ischemia/reperfusion on the ChAT, αPKC,
and Thy-1 immunoreactivities. In addition, morphometric
analysis was carried out to determine the effects of ischemia/reperfusion
on the thickness of the retina. Ischemia for 75 min caused
a change in the nature of the normal GABA and ChAT immunoreactivities
in the rabbit retina and a reduction in the b-wave
of the electroretinogram. When memantine was injected into
the vitreous humour at the onset of an ischemic insult,
the changes in the GABA and ChAT immunoreactivities were
reduced and the recovery of the reduced b-wave
of the electroretinogram after 2 days reperfusion was enhanced
significantly. Ischemia for 60 min followed by 3 days reperfusion
showed a clear change in ChAT immunoreactivity in the rat
retina. The Thy-1 immunoreactivity was only clearly altered
after a reperfusion period of 7 days. Moreover, a measurable
change in the thickness of the inner retinal layers was
detected after 14 days of reperfusion. When given at the
onset of ischemia, memantine counteracted the effect of
ischemia/reperfusion to varying degrees. However, when
memantine was given at the onset of the reperfusion this
was not the case. The combined data show that a single
injection of memantine given i.p. or intravitreally will
protect the retina from a subsequent ischemic insult.
To provide a quantitative description of postnatal retinal expansion in rabbits, a new procedure was developed to map the retinae, which cover the inner surface of hemispheres or parts of rotation ellipsoids, in situ, onto a single plane. This method, as well as the known distribution of Müller cells per unit retinal surface area, were used to estimate the redistribution of specific subpopulations of Müller cells within different topographic regions of the retinae. Müller cells are known to exist as a stable population of cells 1 week after birth and can therefore be used as “markers” for determining tissue expansion. Our results show that differential retinal expansion occurs during development. Peripheral retinal regions expand at least twice as much as the central ones. Furthermore, there is a greater vertical than horizontal expansion. This differential retinal expansion leads to a corresponding redistribution of 5-hydroxytryptamine (5-HT) accumulating amacrine cells. Differential retinal expansion, however, does not account for all of the changes in the centro-peripheral density gradient of cells in the ganglion cell layer (GCL) — mostly retinal ganglion cells — during postnatal development. The changes in the ganglion cell layer were evaluated in Nissl-stained wholemount retinal preparations. Additionally, the difference between expansion-related redistribution of cells in the GCL and Müller cells was confirmed in wholemount preparations where Müller cells (identified as vimentin positive) and cells in the GCL (identified by fluorescent supravital dyes) were simultaneously labeled. It is assumed that many of the ganglion cells within the retinal center are not translocated during retinal expansion, possibly because their axons are fixed. In contrast, 5-HT accumulating amacrine cells — which are interneurons without a retinofugal axon — display a passive redistribution together with the surrounding retinal tissue.
Reduction of blood flow to the rat retina was achieved by either clamping both carotid arteries briefly (24 min) or combining clamping of the carotid arteries with permanent occlusion of the vertebral arteries. Analysis of retinas 6 days after operations showed that GFAP immunoreactivity is expressed throughout the retinal Müller cells, although this was variable in retinas from animals where only the carotid arteries were clamped. GFAP immunoreactivity was not associated with retinal Müller cells from control animals and no obvious neuronal damage was observed in retinas from operated animals. These data suggest that Müller-cell GFAP expression may be used as an index to follow possible processes leading to an ischemic insult.
The response of patients with major depressive illness to citalopram of amitriptyline was compared in a double-blind multi-centre trial. No differences in efficacy were observed, but citalopram had less hypnotic effect and a remarkably lower profile of side-effects.
An in vitro culture system incorporating a cell monolayer was used to induce most activated oncospheres of Taenia ovis to enter post-oncospheral development. Seven distinct developmental phases were recognized during the 23 days required for development to reach a stage similar to that achieved after 14 days in vivo. Secretions or tegumental substance were released during each developmental phase.