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On the existence of products of primes in arithmetic progressions
Get PDFWe study the existence of products of primes in arithmetic progressions, building on the work of Ramaré and Walker. One of our main results is that if q is a large modulus, then any invertible residue class mod q contains a product of three primes where each prime is at most q 6 / 5 + ε . Our arguments use results from a wide range of areas, such as sieve theory or additive combinatorics, and one of our key ingredients, which has not been used in this setting before, is a result by Heath‐Brown on character sums over primes from his paper on Linnik's theorem
Surface mannosylation of dispersion polymerisation derived nanoparticles by copper mediated click chemistry
Get PDFThe synthesis of spherical polymeric nanoparticles containing alkyne surface functionalities for post polymerisation glycosylation is described. The nanoparticles were obtained by a polymerisation induced self-assembly (PISA) inspired methodology in dispersed media by Cu(0) mediated polymerisation. A water soluble poly(ethylene glycol methacrylate-stat-propargyl methacrylate), poly(PEGMA18-stat-PgMA5), macroinitiator was first synthesised and chain extended with 2-hydroxypropyl methacrylate (HPMA) in water using a copper wire catalyst. It was found that irrespective of the macroinitiator to HPMA ratio and the reaction time the desired spherical morphologies (<100 nm) were obtained while the absence other morphologies suggest a deviation from the classical PISA process due to chain termination in the nanoparticle's core. The obtained nanoparticles contained alkyne functionalities in the shell, which were successfully reacted by copper mediated click chemistry with fluoresceine azide and mannosides with hydrophobic and hydrophilic spacers of different lengths. The obtained mannosylated nanoparticles displayed no significant cytotoxicity against human alveolar basal epithelial adenocarcinomic (A549) cells at any dose <0.5 mg mL−1. Preliminary binding studies confirm the ability of the mannosylated nanoparticles to bind to human lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN). The methodology reported here is a convenient route to well-defined spherical and shell-functionalisable nanoparticles to create libraries of bio-active nanomaterials
Protocol for a scoping review to identify research reporting on eating disorders in minority ethnic populations in the UK, Canada, Australia and New Zealand
Get PDFIntroduction Eating disorders (EDs) are common, severe and often life-threatening psychiatric conditions. Notwithstanding stereotypes, EDs affect individuals from all racial and ethnic backgrounds. However, despite similar and in some cases increased prevalence of disordered eating and EDs among minority ethnic groups, there appear to be disparities when it comes to ED diagnosis and treatment. To date, most of the existing literature exploring disordered eating and EDs among minority ethnic groups has been conducted in the USA. The present scoping review aims to examine the extent, range and nature of research activity into disordered eating and EDs in the UK, Canada, Australia and New Zealand providing a comprehensive overview of the existing literature. A special focus will be placed on studies exploring prevalence, access to care and treatment experiences.
Methods and analysis The scoping review framework first outlined by Arksey and O’Malley and improved on by Levac et al was used to guide the development of this scoping review protocol. A detailed systematic search of relevant databases (Medline, EMBASE, PsycINFO, CINAHL and Web of Science) will be conducted. Relevant literature will also be identified from the reference lists of included studies. Two reviewers will independently screen titles and abstracts and full-texts against specified inclusion and exclusion criteria. A third reviewer will resolve disagreements if necessary. Relevant data will be extracted using a data charting form. Quantitative and qualitative summaries of extracted data will be provided
When rules are over-ruled : virtual bargaining as a contractualist method of moral judgment
No full textLooking forwards and backwards : dynamics and genealogies of locally regulated populations
Get PDFWe introduce a broad class of mechanistic spatial models to describe how spatially heterogeneous populations live, die, and reproduce. Individuals are represented by points of a point measure, whose birth and death rates can depend both on spatial position and local population density, defined at a location to be the convolution of the point measure with a suitable non-negative integrable kernel centred on that location. We pass to three different scaling limits: an interacting superprocess, a nonlocal partial differential equation (PDE), and a classical PDE. The classical PDE is obtained both by a two-step convergence argument, in which we first scale time and population size and pass to the nonlocal PDE, and then scale the kernel that determines local population density; and in the important special case in which the limit is a reaction-diffusion equation, directly by simultaneously scaling the kernel width, timescale and population size in our individual based model
Walk a mile in my shoes : perspectives towards sharing of health and experience data among individuals living with sickle cell disorder
No full textAdvancements in digital health technologies (DHTs) mean people are increasingly recording and managing personal health data. As observed during the COVID-19 pandemic, sharing of such data may provide unrivalled opportunities in advancing our understanding of conditions otherwise poorly understood, including rare conditions. A semi-structured focus group (n=25) explored perspectives and experiences of sharing health data among those with a group of rare haematological conditions, sickle cell disorder (SCD). The focus group explored (I) what 'feeling well' looks like; (II) how this could be monitored using DHTs; (III) which data healthcare professionals (HCPs) should pay greater attention to and; (IV) types of data willing to be shared, with whom, and under which conditions. Key themes were further assessed via an online survey (n=50). Patient-relevant measures of condition-management focused on " " SCD, suggesting HCPs did not pay sufficient attention to day-to-day symptom variability. This was juxtaposed against the " " electronic health record (EHR), collecting pre-specified data at pre-determined snapshots of time, not considered reflective of outcomes associated with " " day-to-day. Forty-four-point-seven percent of respondents had previously shared health data. Most were willing to share data concerning symptoms and health service utilisation, but were less willing to share genomic and EHR data. Sixty-one-point-seven percent believed HCPs did not pay enough attention to daily fluctuations in mental and physical health. Financial benefits (74.5%), trust in organisations seeking data (72.3%), and knowing how data will be used (61.7%) were key facilitators of data sharing. Seventy-one percent, 70% and 65.2% had not previously shared health data with the pharmaceutical industry, charitable organisations and digital health interventions respectively, but were open to doing so in the future. Those living with the rare condition SCD were supportive of collecting and sharing data to foster research and improve understanding and outcomes. However, specific requirements were identified to respect privacy and informational needs regarding future use of data. DHTs can be a valuable tool in improving understanding of the day-to-day impact of health conditions, but understanding patient needs is critical in ensuring involvement in the process, as not all data types are considered of equal value, benefit, or risk. [Abstract copyright: 2024 mHealth. All rights reserved.
The ‘Goggle-box’ recording
Get PDFThis methodological article introduces and evaluates the use of the ‘Goggle-box’ recording as an ethnographic data collection method. Simply put, the method means video-recording participants watching television within their own homes, as they experience the meanings and materialities that shape their belonging. I argue that the ‘Goggle-box’ recording provided a creative solution to exploring the mundanity of everyday life, which so often marks leisure experiences. This makes it a valuable method for researchers wishing to: explore the sensoriality of everyday leisure experiences, engage with the many interconnections involved in subjective belonging, and produce more substantiate and sustainable challenges to the privileged exclusivity certain subjectivities benefit from. Therefore, this article invites readers to foster their research imaginations, produce creative responses, and consider alternative ways of knowing in their own practice
All-optical format conversion-based flexible optical interconnection using nonlinear MZI with nested-pump assisted NOLM
Get PDFAn all-optical format conversion (AOFC) scheme of star-m-ary quadrature amplitude modulation (star-mQAM) based on a nonlinear Mach-Zehnder interferometer (MZI) with nested-pump assisted nonlinear optical loop mirror (nested-PA-NOLM) is proposed and numerically simulated. In this scheme, input multi-Gbps star-8QAM signals can be converted into three quadrature phase shift keying (QPSK) signals (namely QPSK-A, -B and -C) through the PA-NOLM under different input power of the signal and the pump. The nonlinear MZI is formed by two PA-NOLMs of the upper and the lower arms, the former and the latter 3-dB optical couplers (OCs), a directional variable optical attenuator (VOA) in the upper arm and a directional variable phase shifter (VPS) in the lower arm. A VOA and a VPS are used to adjust the power ratio (PR) and relative phase shift (RPS) between any two of QPSK-A, -B and -C. When any two adjusted signals in QPSK-A, -B and -C are coherently superposed, the aggregated star-8QAM signal can be extracted again. Furthermore, the proposed scheme can also be used to convert the 20 Gbps bipolar 4-ary pulse amplitude modulation (PAM4) signal into two 10 Gbps BPSK signals and a 20 Gbps QPSK signal. When the proposed scheme is combined with the phase-sensitive amplification (PSA), it can also be used to convert one 16QAM into two QPSK signals. The scheme performance is analyzed via constellation diagrams, power waveforms, the error vector magnitude (EVM) and the bit error rate (BER) of the optical signals. The scheme can not only be deployed in optical gateways to connect optical networks using different modulation formats, but also has a potential applied advantage in security information transmission between different optical networks
Dataset to support: 'Polymorph identification for flexible molecules: linear regression analysis of experimental and calculated solution- and solid-state NMR data'
No full textThis document presents the raw data file from the solid-state NMR CASTEP calculations recorded by Mohammed Rahman and torsion data recorded by Hugh R.W. Dannatt and Charles D. Blundell