Identifying biotic interactions which drive the spatial distribution of a mosquito community

Background: Spatial variation in the risk of many mosquito-borne pathogens is strongly influenced by the distribution of communities of suitable vector mosquitoes. The spatial distributions of such communities have been linked to the abiotic habitat requirements of each constituent mosquito species, but the biotic interactions between mosquitoes and other species are less well understood. Determining which fauna restrict the presence and abundance of key mosquito species in vector communities may identify species which could be employed as natural biological control agents. Whilst biotic interactions have been studied in the laboratory, a lack of appropriate statistical methods has prohibited the identification of key interactions which influence mosquito distributions in the field. Joint species distribution models (JSDMs) have recently been developed to identify biotic interactions influencing the distributions of species from empirical data. Methods: We apply a JSDM to field data on the spatial distribution of mosquitoes in a UK wetland to identify both abiotic factors and biotic interactions driving the composition of the community. Results: As expected, mosquito larval distributions in this wetland habitat are strongly driven by environmental covariates including water depth, temperature and oxidation-reduction potential. By factoring out these environmental variables, we are able to identify species (ditch shrimp of the genus Palaemonetes and fish) as predators which appear to restrict mosquito distributions. Conclusions: JSDMs offer vector ecologists a way to identify potentially important biotic interactions influencing the distributions of disease vectors from widely available field data. This information is crucial to understand the likely effects of habitat management for vector control and to identify species with the potential for use in biological control programmes. We provide an R package BayesComm to enable the wider application of these models

Social gradients in the receipt of medication for attention-deficit hyperactivity disorder in children and young people in Sheffield

Background Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder characterised by inattention and hyperactivity-impulsivity that can affect people throughout their lifecourse. A social gradient exists in the prevalence of ADHD in the UK. Studies in other countries have shown that social gradients also exist in the receipt of medication for ADHD. Socioeconomic position is potentially an unrecognised and modifiable factor in children and young people’s receipt of medication for ADHD in the UK. Aim The aim of the study was to investigate if socioeconomic could explain in part whether or not children and young people in Sheffield are receiving medication for ADHD. Method We used multivariable logistic regression modelling to investigate whether socioeconomic could explain variation in receipt of medication for ADHD in children and young people in a cross sectional study. We collected data from 1354 children and young people with a diagnosis of ADHD across three Sheffield centres between January and December 2016. Independent variables were age, sex, religion, ethnicity, comorbidities, and Index of Multiple Deprivation decile (derived from home postcode). Results Our results showed a social gradient in the receipt of medication for ADHD (p<0.01); an increase in one decile of the Index of Multiple Deprivation was associated with 10% lower odds of receipt of medication for ADHD (aOR 0.90; 95%CI 0.84–0.970). Conclusion Children and young people from more deprived backgrounds are more likely to receive medication for ADHD. This is the first time that a social gradient in children and young people’s receipt of medication for ADHD has been shown in a UK sample

Manipulation of drugs to achieve the required dose is intrinsic to paediatric practice but is not supported by guidelines or evidence

Background: A lack of age-appropriate formulations can make it difficult to administer medicines to children. A manipulation of the dosage form may be required to achieve the required dose. This study aimed to describe medicines that are manipulated to achieve the required dose in paediatric practice.Method: A structured, undisguised observational study and postal survey. The observational study investigated drug manipulations occurring in clinical practice across three sites. The questionnaire, administered to a sample of paediatric nurses throughout the UK, surveyed manipulations conducted and nurses' experiences and views.Results: The observational study identified 310 manipulations, of which 62% involved tablets, 21% were intravenous drugs and 10% were sachets. Of the 54 observed manipulations 40 involved tablets with 65% of the tablets being cut and 30% dispersed to obtain a smaller dose. 188 manipulations were reported by questionnaire respondents, of these 46% involved tablets, 12% were intravenous drugs, and 12% were nebuliser solutions. Manipulations were predominantly, but not exclusively, identified in specialist clinical areas with more highly dependent patients. Questionnaire respondents were concerned about the accuracy of the dose achieved following manipulations and the lack of practice guidance.Conclusion: Manipulations to achieve the required dose occur throughout paediatric in-patient settings. The impact of manipulations on the efficacy of the drugs, the accuracy of the dose and any adverse effects on patients is not known. There is a need to develop evidence-based guidance for manipulations of medicines in children

Multimode Memories in Atomic Ensembles

The ability to store multiple optical modes in a quantum memory allows for increased efficiency of quantum communication and computation. Here we compute the multimode capacity of a variety of quantum memory protocols based on light storage in ensembles of atoms. We find that adding a controlled inhomogeneous broadening improves this capacity significantly.Comment: Published version. Many thanks are due to Christoph Simon for his help and suggestions. (This acknowledgement is missing from the final draft: apologies!

Efficient spatially-resolved multimode quantum memory

We propose a method that enables efficient storage and retrieval of a photonic excitation stored in an ensemble quantum memory consisting of Lambda-type absorbers with non-zero Stokes shift. We show that this can be used to implement a multimode quantum memory storing multiple frequency-encoded qubits in a single ensemble, and allowing their selective retrieval. The read-out scheme applies to memory setups based on both electromagnetically-induced transparency and stimulated Raman scattering, and spatially separates the output signal field from the control fields

Cohort Profile: The Health Survey for England

To monitor the health of the public in England, UK, the Central Health Monitoring Unit within the UK Department of Health commissioned an annual health examination survey, which became known as the Health Survey for England (HSE). The first survey was completed in 1991. The HSE covers all of England and is a nationally representative sample of those residing at private residential addresses. Each survey year consists of a new sample of private residential addresses and people. The HSE collects detailed information on mental and physical health, health-related behaviour, and objective physical and biological measures in relation to demographic and socio-economic characteristics of people aged 16 years and over at private residential addresses. There are two parts to the HSE; an interviewer visit, to conduct an interview and measure height and weight, then a nurse visit, to carry out further measurements and take biological samples. Since 1994, survey participants aged 16 years and over have been asked for consent to follow-up through linkage to mortality and cancer registration data, and from 2003, to the Hospital Episode Statistics database, thus converting annual cross-sectional survey data into a longitudinal study. Annual survey data (1994–2009) are available through the UK Data Archive

Towards high-speed optical quantum memories

Quantum memories, capable of controllably storing and releasing a photon, are a crucial component for quantum computers and quantum communications. So far, quantum memories have operated with bandwidths that limit data rates to MHz. Here we report the coherent storage and retrieval of sub-nanosecond low intensity light pulses with spectral bandwidths exceeding 1 GHz in cesium vapor. The novel memory interaction takes place via a far off-resonant two-photon transition in which the memory bandwidth is dynamically generated by a strong control field. This allows for an increase in data rates by a factor of almost 1000 compared to existing quantum memories. The memory works with a total efficiency of 15% and its coherence is demonstrated by directly interfering the stored and retrieved pulses. Coherence times in hot atomic vapors are on the order of microsecond - the expected storage time limit for this memory.Comment: 13 pages, 5 figure

Theory of noise suppression in {\Lambda}-type quantum memories by means of a cavity

Quantum memories, capable of storing single photons or other quantum states of light, to be retrieved on-demand, offer a route to large-scale quantum information processing with light. A promising class of memories is based on far-off-resonant Raman absorption in ensembles of $\Lambda$-type atoms. However at room temperature these systems exhibit unwanted four-wave mixing, which is prohibitive for applications at the single-photon level. Here we show how this noise can be suppressed by placing the storage medium inside a moderate-finesse optical cavity, thereby removing the main roadblock hindering this approach to quantum memory.Comment: 10 pages, 3 figures. This paper provides the theoretical background to our recent experimental demonstration of noise suppression in a cavity-enhanced Raman-type memory ( arXiv:1510.04625 ). See also the related paper arXiv:1511.05448, which describes numerical modelling of an atom-filled cavity. Comments welcom