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FSO-based HAP-assisted multi-UAV backhauling over F channels with imperfect CSI
Get PDFYesNon-terrestrial Network (NTN), utilizing highaltitude platforms (HAP)-based free-space optical (FSO) backhaul and unmanned aerial vehicles (UAV) for last-mile access, is a feasible and promising architecture to achieve high data rate and seamless network coverage in the future 6G era. Effective resource allocation emerges as a pivotal concern for such networks. This paper addresses the data allocation issue for FSO backhaul from the HAP to multiple UAV-mounted base stations (BSs) under the constraints of ground users’ requested data rates. We introduce frame allocation schemes (FAS), including rate adaptation with constraints (RAC)- and rate/power adaptation (RPA)-aided FAS. The key idea of these schemes is to allocate data frames effectively based on UAV’s turbulence channel conditions, which aims to (i) guarantee the quality of services (QoS), (ii) retain both latency and throughput fairness, and (iii) minimize the transmitted power. Furthermore, the performance of these schemes is also analyzed under the impact of imperfect channel state information (CSI). We newly derive the channel probability density function (PDF) and the cumulative density function (CDF), considering the imperfect CSI due to channel estimation and quantization errors. Capitalizing on the derived PDF and CDF, different performance metrics are analytically obtained, incorporating combined effects of cloud coverage, transceiver misalignment, Fisher-Snedecor F turbulence, and angle-of-arrival (AoA) fluctuations. Numerical results demonstrate the effectiveness of our design proposals over the state-of-the-art. Finally, Monte Carlo simulations are employed to validate the analysis
The perspectives of caregivers and health service providers on barriers to clubfoot management in Puri-Urban health facility in Ghana
Get PDFYesPurpose: Clubfoot is a common disabling condition that is prevalent across all populations. Approximately, one out of
750 children globally suffers from clubfoot, and around 150,000 to 200,000 children are born with clubfoot every year
with 80% of the cases occurring in developing countries. Clubfoot can result in mobility impairments when not properly
managed and researchers have argued that understanding knowledge and perceptions are key components to early
identification and effective management of clubfoot. The study explored the barriers to clubfoot management from the
perspectives of caregivers and healthcare providers in Duayaw Nkwanta, Ghana.
Methods: A total of 26 participants made up of 22 caregivers of children with clubfoot and six healthcare providers
were purposively sampled for the study guided by a set of inclusion and exclusion criteria. Qualitative data were
collected using a semi-structured interview guide through in-depth face-to-face interviews. Interviews were transcribed
and analyzed thematically and presented as findings.
Results: High cost of treatment, long travel distance, long hours spent at the treatment facility, non-availability of
clubfoot treatment services, late reporting of clients for treatment, and non-compliance of parents/caregivers with
treatment protocols were identified as the barriers to effective management of clubfoot.
Conclusion: These findings have substantial implications for current interventions to effectively manage clubfoot in
Ghana
Frequency-of-seeing curves (psychometric functions) for perimetric stimuli in age-related macular degeneration
Get PDFYesPurpose: Frequency-of-seeing (FoS) curves (psychometric functions) for perimetric stimuli have been widely used in computer simulations of new visual field test
procedures. FoS curves for age-related macular degeneration (AMD) are not available in the literature and are needed for the development of improved microperimetry test procedures, which are of particular interest for use as clinical trial
endpoints.
Methods: Data were refitted from a previous study to generate FoS curves for 20
participants with AMD, each tested at nine locations within the central 10°. Stimulus
parameters, background luminance and dB scale were matched to the MAIA-2 microperimeter, and stimuli were presented in a method of constant stimuli to build
up FoS curves over multiple runs. FoS curves were fitted with a modified cumulative Gaussian function. The relationship between sensitivity and slope of fitted FoS
curves was modelled by robust linear regression, producing models both with and
without an eccentricity parameter.
Results: FoS curves were satisfactorily fitted to data from 174 visual field locations in 20 participants (age 65–83 years, 11 female). Each curve was made up
of a median of 243 (range 177–297) stimulus presentations over a median of 12
(range 9–32) levels. Median sensitivity was 25.5dB (range 3.8–31.4dB). The median
slope (SD of fitted function) was 1.6dB (range 0.5–8.5dB). As in previous studies of
other conditions, the slope of fitted FoS curves increased as sensitivity decreased
(p<0.001).
Conclusions: FoS are provided for participants with AMD, as well as models of the
relationship between sensitivity and slope. These fitted models and data may be
useful for computer simulation studies of microperimetry procedures. Full details
of the fitted curves are provided as supporting information
A needle in a haystack: Landscape survey and archaeological detection experiments in Apalachee Bay
Get PDFThis paper presents the results of a pilot landscape-scale seismic survey undertaken in Apalachee Bay, Florida, across a submerged landscape that contains dozens of Pre-Contact sites. In addition to the goals of improving the geophysical and remote sensing ground model for this submerged landscape, the survey also sought to undertake the first independent scientific test of the contentious ‘HALD’ methodology, an acoustic resonance method that it is laimed to identify knapped lithic artefacts at and/ or below the seabed through the identification of distinct ‘haystack’ responses. The results of this work indicate that the HALD method, as currently described, produces results that could not be scientifically replicated in this survey. We conclude that any HALD ‘haystack’ signal should therefore not be considered as an example of detection of human-modified lithic material but rather as a geophysical anomaly that requires additional constraints before it can be used to reliably identify human-modified lithic materials. Thus, although the authors note that laboratory studies have successfully produced an acoustic signal in human-modified lithics, the field-based methods remain yet to be reliably determined. In addition to these results, the landscape mapping survey also recorded valuable information on buried and previously unrecorded landscape features that have archaeological significance and that may guide future site prospection. We therefore conclude that despite the results of the HALD test, the well-preserved submerged landscape of Apalachee Bay region provides a highly useful testing ground for methods that can be deployed elsewhere globally.UK Research and Innovation (UKRI) for the Life on the Edge Project (LOTE) via a UKRI Future Leaders Fellowship (Grant No. MR/W007797/1)
Cultural hierarchies in health: Does inherited sociocultural position (biraderi) shape diet and nutrition among British Pakistani children? Protocol for a mixed-methods study
Get PDFYesThis study aims to explore links between biraderi–a form of identity-based social grouping and stratification which cuts across religions among South Asians–and infant and child nutrition among British Pakistanis using data from the Born in Bradford cohort study. The study will entail a mixed-methods approach to (i) develop an operational framework of biraderi for epidemiologic analyses and apply it to longitudinal data from the Born in Bradford cohort study, (ii) quantify and describe child nutrition and dietary patterns for biraderi sub-groups, and (iii) investigate whether known mechanisms of identity-based segregation, graded inequality, and network effects operate through diet and nutrition in the UK. Using Krieger’s ecosocial theory as an integrative framework we will (iv) re-conceptualise and interpret the role of biraderi / caste in the social construction and embodied experience of how infants and children eat in the UK. Following a literature review on biraderi and health, we will convene and consult a lay consultation group in Bradford through focus groups and academic experts through a Delphi study to guide planning, implementation, interpretation and dissemination of our secondary data analysis. In addition to being the first study to look at biraderi-based nutritional inequalities in the UK, our study is innovative in that we will formally involve experts and users in the design and interpretation of our quantitative analyses. Findings will be applicable in any part of the world where children experience disadvantage linked to sociocultural hierarchy and identity. Our findings will be of particular use in (i) identifying women and children at particular risk of suboptimal breastfeeding practices, poor complementary feeding, and unhealthy diets in primary school in the UK, and (ii) elucidating the sociocultural pathways through which inequalities in population health nutrition outcomes are expressed.ESRC Secondary Data Analysis Initiative; Economic and Social Research Council and Medical Research Council [Grant reference: ES/X012816/1
Technology for fast-tracking high-risk head and neck cancer referrals: Co-designing with patients
Get PDFYesBackground: Head and Neck Cancer (HNC) is the eighth most prevalent global cancer. Timely recognition of
symptoms is crucial for reducing mortality rates. The EVolution of a patiEnt-REported symptom-based risk
stratification sySTem to redesign the suspected Head and Neck cancer referral pathway (EVEREST-HN) study
aims to develop and evaluate a risk stratification tool using patient reported symptoms, which will be populated
remotely in the community before the patient is seen by the clinician to hasten HNC diagnosis. EVEREST-HN will
design a patient SYmptom iNput Clinical (SYNC) system to gather patient symptom data and calculate a risk
score to aid clinicians in identifying high-risk cases. This identification potentially allows for high-risk patients to
be seen sooner, thereby improving patient outcomes.
Methods: Three workshop sessions were conducted involving a total of 17 unique participants, with several
contributing to multiple sessions: nine in the co-design session, six in the validation session, and nine in the
evaluation session. The co-design session employed online collaboration with patients’ representatives. Thematic
analysis was used to identify requirements and concerns informing the development of a low-fidelity prototype.
The validation session assessed whether the prototype aligned with patient expectations. In the evaluation
session, participants interacted with an online prototype and provided further feedback.
Results: During the co-design workshop, participants emphasized the need for a concise and clear SYNC system
questionnaire for reporting suspected HNC symptoms. Concerns were raised about questionnaire length, language
clarity, and the inclusion of probing questions. Participants suggested concise questions using lay language,
incorporating visual aids for topics like alcohol and tobacco use, and making the sexual activity question
optional. Recommendations included diverse language options, hard copies for non-English speakers, and phone
call options for those uncomfortable with screen-based technology. The validation workshop confirmed that the
prototype reflected participants’ ideas. Feedback highlighted the need for call-back features to help those not
confident with technology and the need to present symptom questions first before social background questions.
Feedback from the evaluation demonstrated a commitment to efficiency, and continuous improvement.
Conclusion: This study aims to develop the SYNC system to enhance efficiency of suspected HNC referrals. The
workshops highlighted the importance of end-user inclusiveness in the system development life cycle, with
collaboration with stakeholders and repeated feedback, providing crucial insights for ensuring the SYNC system
effectively addresses the needs and concerns of patients in the context of HNC diagnosis.This study is funded by the NIHR Programme Grants for Applied Research (NIHR202862)
Qualitative study exploring the design of a patient-reported symptom-based risk stratification system for suspected head and neck cancer referrals: protocol for work packages 1 and 2 within the EVEREST-HN programme
Get PDFYesIntroduction: Between 2009/2010 and 2019/2020, England witnessed an increase in suspected head and neck cancer (sHNC) referrals from 140 to 404 patients per 100 000 population. 1 in 10 patients are not seen within the 2-week target, contributing to patient anxiety. We will develop a pathway for sHNC referrals, based on the Head and Neck Cancer Risk Calculator. The evolution of a patient-reported symptom-based risk stratification system to redesign the sHNC referral pathway (EVEREST-HN) Programme comprises six work packages (WPs). This protocol describes WP1 and WP2. WP1 will obtain an understanding of language to optimise the SYmptom iNput Clinical (SYNC) system patient-reported symptom questionnaire for sHNC referrals and outline requirements for the SYNC system. WP2 will codesign key elements of the SYNC system, including the SYNC Questionnaire, and accompanying behaviour change materials.
Methods and analysis: WP1 will be conducted at three acute National Health Service (NHS) trusts with variation in service delivery models and ensuring a broad mixture of social, economic and cultural backgrounds of participants. Up to 150 patients with sHNC (n=50 per site) and 15 clinicians (n=5 per site) will be recruited. WP1 will use qualitative methods including interviews, observation and recordings of consultations. Rapid qualitative analysis and inductive thematic analysis will be used to analyse the data. WP2 will recruit lay patient representatives to participate in online focus groups (n=8 per focus group), think-aloud technique and experience-based codesign and will be analysed using qualitative and quantitative approaches.
Ethics and dissemination: The committee for clinical research at The Royal Marsden, a research ethics committee and the Health Research Authority approved this protocol. All participants will give informed consent. Ethical issues of working with patients on an urgent cancer diagnostic pathway have been considered. Findings will be disseminated via journal publications, conference presentations and public engagement activities.This work was supported by NIHR Programme Grants for Applied Research (grant number: NIHR202862)
A Comprehensive Experimental and Computational Investigation on Estimation of Scour Depth at Bridge Abutment: Emerging Ensemble Intelligent Systems
No full textNoSeveral bridges failed because of scouring and erosion around the bridge elements. Hence,
precise prediction of abutment scour is necessary for the safe design of bridges. In this
research, experimental and computational investigations have been devoted based on 45
flume experiments carried out at the NIT Warangal, India. Three innovative ensemblebased
data intelligence paradigms, namely categorical boosting (CatBoost) in conjunction
with extra tree regression (ETR) and K-nearest neighbor (KNN), are used to accurately
predict the scour depth around the bridge abutment. A total of 308 series of laboratory
data (a wide range of existing abutment scour depth datasets (263 datasets) and 45 flume
data) in various sediment and hydraulic conditions were used to develop the models. Four
dimensionless variables were used to calculate scour depth: approach densimetric Froude
number (Fd50), the upstream depth (y) to abutment transverse length ratio (y/L), the abutment
transverse length to the sediment mean diameter (L/d50), and the mean velocity to
the critical velocity ratio (V/Vcr). The Gradient boosting decision tree (GBDT) method
selected features with higher importance. Based on the feature selection results, two combinations
of input variables (comb1 (all variables as model input) and comb2 (all variables
except Fd50)) were used. The CatBoost model with Comb1 data input (RMSE = 0.1784,
R = 0.9685, MAPE = 10.4724) provided better accuracy when compared to other machine
learning models
Pressure and velocity profiles over a weir using potential flow model
Get PDFYesA potential flow model of the semi-inverse type is proposed to simulate flow over round crested weirs. This technique involves the construction of only streamlines over the weir instead of constructing the entire flow net. A Serre–Green–Naghdi (SGN) equation is employed to determine the initial free-surface profile, which is solved using a combined finite volume-finite difference scheme. The potential flow equations were numerically solved using a five-point central finite difference scheme. The model was applied to define the pressure and velocity fields in channel controls involving transcritical flow, such as the Gaussian weir, parabolic weir, and semicircular weir. The impact of streamline curvature on pressure and velocity distributions was investigated in the study. The curvature of the streamline strongly influenced the rise and drop of the bed pressures along the test section. A semicircular weir experiment was also conducted to validate the pressure and velocity profiles obtained using the proposed 2-D fluid flow model. The computed pressure and flow profiles from the solution of the potential flow equation agree perfectly with the present experiment and similar experiments available in the literature. In conclusion, the SGN equation provides an excellent initial profile to solve a 2-D ideal fluid flow numerically
Evaluating the impact of the Health Access for Refugees Project on people who are refugees or seeking asylum in Northern England
Get PDFYesEvidence demonstrates that people who are seeking asylum and refugees face individual, institutional and system-level barriers when accessing health services. Health Access for Refugees’ Project (HARP) is a UK initiative increasing access to health care within this community through a series of interventions. This study explored the impact of HARP on health service access, experiences and outcomes for clients, and how volunteers and staff addressed institutional and system-level barriers.
Methods:
In summer 2020, we conducted qualitative telephone interviews with four HARP clients, eight clients who became volunteers, seven further volunteers and three staff members.
Results:
The educational aspect of the interventions supported clients navigating the complex UK health care system while promoting independence in accessing health care. Advocacy by volunteers and staff was important in challenging barriers at individual and institutional levels. Staff challenged the asylum system, by improving information around entitlement to health care and addressing barriers to registering with a General Practitioner (GP).
Conclusions:
Interventions such as those provided by HARP can address different levels of barriers to support people accessing health care provision. This can be achieved through training health professionals and working with peers to support access to care and to develop self-advocacy. However, stable long-term funding is essential to ensure the sustainability of these initiative.The Big Lottery via the Refugee Council, UK