bluuebunny/crossref_metadata_2025 huggingface dataset:
Faster R-CNN and YOLOv3: a general analysis between popular object detection networks
Authors: Dong Wenbo
Published: September 2023

Computer vision is developing really fast in recent years, and object detection is now one of the hottest topics. faster region-based convolutional neural network (faster R-CNN) and You Only Look Once (YOLOv3) are two popular modules to solve object detection problems, but they are implemented in different ways and thus have different performance in practice. This article is going to introduce these two modern modules and make a few experiments to compare the performance of each module with various datasets. This analysis will focus on speed, accuracy and the performances in different situations. Two specific studies will be mentioned as two typical examples of object detection application: face mask detection and greenhouse detection from satellite images. At last, the article will draw out a conclusion, make some suggestions for the choice of faster R-CNN and YOLOv3 and make a prospect for the future. It turns out that generally faster R-CNN fits tasks that require high accuracy better and YOLOv3 can realize real-time detection tasks.
Performance analysis of robustness of BERT model under attack
Authors: Chen Xi
Published: September 2023

With the aim of testing the robustness of machine learning models, this paper tests the performance of five classification models based on IMDB datasets. Furthermore, in this work, two types of sentence embeddings generated by word2vec and BERT are added with the noise of the normal distribution with different intensities. They are fed into the Support Vector Machine for testing. The experimental results show that the performance of the model slowly decreases as the noise intensity is increased. BERT-based sentiment embedding reduces less than Word2vec-based sentiment embedding. This paper believes that this experimental phenomenon can be used as a basis to support the robustness of BERT representation learning. At the same time, this paper also noted that the previous work experimented with perturbating the BERT model by replacing the words in the original text of the IMDB dataset, causing the BERT model performance to drop sharply. However, the experiment in this paper tested the robustness of the BERT model by embedding tampering, and the experimental results were stable. In this paper, it is assumed that word substitution and embedding interference are possible situations when operating the model. Therefore, for the two different experimental phenomena, this paper plans to design more detailed experiments in the next work to check the robustness of the model.
Channel capacity on visible light communication
Authors: Wan Yukun
Published: September 2023

As a typical application scheme of OWC (Optical Wireless Communication), VLC (Visible Light Communication) plays a more vital role in our daily life. It is expected to be used in the fields of vehicle communication, 6G network, underwater wireless communication, etc. Although so many achievements on VLC have been obtained, researchers still have some obstacles to overcome. Channel capacity as an important quota to evaluate communication quality deserves researchers to study further. This paper not only discusses the basic theory and combines the results of some recent studies on visible light channel capacity, but also highlights a promising application prospect and advantages over other communication methods, including RF (radio frequency), and fiber optical. This paper draws a conclusion that VLC is mainly used in indoor and short-distance communication. There is still a long way to apply VLC in long-distance communication and overcome the fading problem.
The gap between theoretical computational theories and application models
Authors: Yang Chengge
Published: September 2023

This paper examined two key generalization assumptions in the theoretical and computational fields and discussed three dominant pre-training models from multiple computer science concentrations. Then, this paper illustrated the increasingly severe gap between theoretical research and model applications for current machine learning studies. This paper discussed four advanced concepts in academia regarding possible solutions for the gap. The researchers developed these concepts to redirect future machine learning work by helping the academia re-understand the concept of “learning” and its appropriate implementation in the machine learning field. Finally, one possible reason for such a gap to exist is explained, and based on the interpretation of advanced concepts, possible solutions the academia can try to implement are also discussed.
The classification of human brain tumors with machine learning
Authors: Ma Zihan , Lin Ziwei
Published: September 2023

This paper aims to report human brain tumor classification based on machine learning. Brain tumors have long been regarded as one of the deadliest tumors. Conventionally, without the assistance of automation tools, brain tumor diagnosis is a skill-demanding work for the doctors and a time-consuming burden on the medic system. Applying machine learning to clinical medicine and classifying brain tumors enables physicians to increase their diagnosis correctness and allows the health system to treat more patients. This paper covers the methods used in the research: the dataset, network models, algorithm, and implementation. The experiment results and discussion section follow this. Focusing on comparing and discussing convolutional neural networks’ performance and resource consumption under different network settings and network models. In the experiment, by feeding the MRI images to the network, the network automates the results indicating whether a tumor is detected in the image and classifies the underlying tumor. The experiment results indicate Machine Learning’s great accuracy of 93.38 percent in classifying brain tumors and the significant correlations between the model’s performance and resource cost, and network settings as well as model complexity.
A time-dependent SEIRS model for COVID-19 in China (mainland)
Authors: Huang Zeyan
Published: September 2023

In the spring of 2022, two years after the onset of the coronavirus pandemic, a second worldwide outbreak is underway, with the number of patients infected with COVID-19 much higher than the peak during the first outbreak. Moreover, the second outbreak was not prevented in mainland China by a series of management measures with few local infections and mandatory quarantine of incoming persons. In this paper, we construct a compartmental model that includes exposed and isolated individuals to address the fact that the COVID-19 virus cannot be permanently immunized and to consider the isolation and treatment process in China. The model is used to analyze which factors have an impact on secondary outbreaks and uses the basic reproduction number to represent the outbreak. We obtained the expression for the basic reproduction number by calculating the basic reproduction number of the model. We used MATLAB to perform sensitivity analysis on each variable included in the expression for the basic reproduction number. In the sensitivity analysis, the increase in the basic reproduction number indicates that the rate of virus transmission and the rate of antibody failure are more critical to the pandemic. Reducing these rates can be effective in mitigating the epidemic. Also, the sensitivity analysis showed that increasing the vaccination rate does not help to reduce the basic reproduction number effectively. Therefore, the Chinese government should urge people to continue wearing masks to reduce the route and likelihood of the COVID-19 virus transmission and could appropriately reduce funding for vaccine promotion until a long-term effective vaccine is invented.
A 3D UAV path planning model based on improved A* algorithm and DEM data
Authors: Liu Bingqi , Lyu Yecheng
Published: September 2023

Unmanned aerial vehicles (UAVs) have been widely used in different tasks. Path planning is the most important factor in the operation of UAVs. This paper proposes a 3D path planning method based on an improved A* algorithm to train the UAV to fly in a real-world environment. The terrain data is first processed with a digital elevation model (DEM). Then the cost function, which balances route efficiency and environmental factors such as weather threats, is built. The available action space for the UAV is reduced considering the manoeuvrability of the vehicle. An improved A* algorithm is used to solve the search model, and the efficiency is enhanced by optimizing the data structure and building a weighted A* algorithm. Simulation results show that the method performed well in planning an optimal path in a 3D environment, and the algorithm is simple and efficient. This work contributes to path planning for UAVs in different missions.
Kernels with peripheral vison: weights of different significance
Authors: He Zixuan
Published: September 2023

The visual field of humankind which is generally composed of central and peripheral vison has different acuity at different spots, while in a convolution layer in convolution neural networks, different weights in a kernel are of the same significance. In order to attach weights with decreasing significance from the center of the kernel to its edge, this paper proposes kernels with peripheral vison, imitating the variable acuity of the human’s visual field. It is achieved by adding a module to the loss function, and a comparation between its implements in Residual Network (ResNet) and GoogLeNet on CIFAR100 is provided in this paper. With this method, kernels whose weights have different sensitivity of the input data are created. It will consume insignificant energy, since it is only functioned when training. The improvements in valid accuracy of ResNet and GoogLeNet are 0.6 percent and 2 percent. It can be easily attached to most structures, improving the accuracy of these structures.
A novel markov random field segmentation method for SAR images
Authors: Zhang Jiangxue , Sun Lujie
Published: September 2023

The synthetic aperture radar(SAR) images is difficult to be segmented by traditional Hidden Markow Random Field(HMRF)-based segmentation method, a novel HMRF-based segmentation method for SAR images is proposed in this article. The method utilizes more spacial information of SAR image model by involving the intensity differences between pixels in the potential function. An initial segmentation result is obtained by K-means method. Then accurate segmentation is carried out by the novel MRF-based segmentation method. The result showed that this method is better than the traditional HMRF one both in noise filtering and miss classification ratio.
Research on compression pruning methods based on deep learning
Authors: Cai Mingzhuo , Su Yihong , Wang Binyu , Zhang Tianyu
Published: September 2023

In the past decade or so, deep neural networks have continuously refreshed the best performance in tasks such as computer vision and natural language processing, and have become the most concerned research directions. Although deep neural networks have significant performance, they are difficult to deploy on hardware-constrained embedded and mobile devices due to their huge number of parameters, computational and storage costs. Therefore, in recent years, the lightweight design of network structure has gradually become a cutting-edge and popular direction, improving the operation speed and optimizing the storage space under the premise of maintaining the accuracy of the neural network. In this paper, the results achieved by domestic and foreign scholars in deep learning model compression are sorted and classified, and the methods of network pruning, model quantification, knowledge distillation, and lightweight network design are summarized, and the compression effect of related methods on known public models is summarized. Finally, the possible directions, application directions and development trends of future neural network model lightweight research are prospected.
Mechanical characteristics and stretch-bend failure analysis on ultra high frequency pulsed gas tungsten arc welded thin FSS 409/430 dissimilar joints
Authors: Nagarajan Anandharajan , Marimuthu Balakrishnan
Published: September 2023

The Mechanical and Stretch-Bend Failure studies on Ultra High Frequency Pulsed Gas Tungsten Arc Welded dissimilar joints of AISI409-AISI430 Ferritic Stainless Steels were conducted. Welding was conducted with 5 ultra high frequencies (50 Hz, 150 Hz, 250 Hz, 350 Hz, 450 Hz). Mechanical characteristics evaluation on the joints included tensile strength, microhardness variations across the welds and creep. Microstructural and metallurgical investigations included weld cross section evaluation, comparing grain variations in high, medium and low thermal heat affected zones, weld zones and base material region. Stretch bend failure studies included studies on angular distortion, fracture limit strain, and coefficient of friction. Tests revealed that joints welded at 350 Hz was better, compared to other joints. Dissimilar AISI409-AISI430 joint fabricated at 350 Hz exhibited 267 ± 3 MPa as yield and 409 ± 6 MPa and as ultimate tensile strength. Its creep fracture duration was 72.7 min (highest among the joints). Microstructural studies revealed grain growth, partially coarse and partially fine grains in heat affected zones. Depending on the difference in grain sizes, on both sides of the welds, heat affected regions were identified as three distinct zones. In AISI430 side; high temperature austenitic, martensitic, delta ferrites and in AISI409 side; needle like martensitic structures, mixture of ferritic-austenitic, δ-ferrite with carbide precipitation were found in high, medium and low thermal heat affected zones, respectively. On increasing the ultra high frequency pulses, angular distortion increased, fractures changed from tensile/shear type to mixed type. In shear bend tests, on increasing the ratio of radius: thickness, fracture limit strain on outer surface, across sheet thickness, due to stretching increased.
Application of lever law in dual-cluster formulas model to interpret eutectic and bulk metallic glass
Authors: Chen Jixiang , Li Shilong , Sha Xiaosong , Dou Yuehui , Wang Shuo , Cheng Yi
Published: September 2023

It is well known that the structure of bulk metallic glass has a close relationship with that of its crystalline eutectic phase, but how this is manifested on the atomic scale is not yet clear. The present paper further develops and optimizes dual-cluster formulas model to describe the eutectic and bulk metallic glass, as C1[(principal cluster)1(glue atom)1 or 3] + C2[(principal cluster)2(glue atom)1 or 3]. C1, C2 are the proportions governed by the lever law, and the two principal clusters which have the highest atomic close-packing efficiency and large degree of isolation are derived from the eutectic-related phases. Cu-Zr binary system are studied using this model and the results match well with the experiments. According to dual-cluster formulas and valence electrons, the correlation between deep eutectic and bulk metallic glass may be disclosed, and a detailed step towards composition design of bulk metallic glass is established as well.
Meta-learning-based estimation of the barrier layer thickness in the tropical Indian Ocean
Authors: Qi Jifeng , Qu Tangdong , Yin Baoshu
Published: September 2023

Accurately estimating the barrier layer thickness (BLT) is crucial for enhancing our understanding of the ocean’s role in climate variability on both regional and global scales. Here, we propose a meta-learning-based ensemble model to estimate the BLT using satellite observations in the tropical Indian Ocean. The results show that the meta-learning-based ensemble model outperforms the three individual models in terms of spatial distribution and accuracy, with significantly reduced root mean square errors in the Southeast Arabian Sea, Bay of Bengal, and eastern equatorial Indian Ocean. Furthermore, we found that sea surface salinity plays the most significant role in the estimation of BLT, highlighting the dominant influence of salinity stratification. These preliminary results provide an insight into the feasibility of predicting the BLT using satellite observations and have implications for studying the upper ocean dynamics using machine learning techniques.
Multidecadal variability of dust activity in Gobi desert and its connection with the pacific decadal oscillation
Authors: Huo Yanfeng , Bai Dongping , Liu Lin , Dong Zizhen , Xun Shangpei , He Binfang , Wu Wenyu , Chen Xintong , Zhang Hongqun
Published: September 2023

The multidecadal changes of dust column mass density (DCMD) in Gobi desert (GD) in spring are investigated based on the Modern-Era Retrospective analysis for Research and Applications version 2 dataset. In addition, the possible effects of the atmospheric circulation and sea surface temperature (SST) forcing on the multidecadal changes are analyzed. Results show that the dust aerosol over GD experienced a decadal change in 1999 with about 30% higher dust loading during 2000–2013 in comparison to that during 1987–1999. Further analysis indicates that the decadal change of dust aerosol over GD is attributed to the more strengthened northwesterly wind anomaly extending from lower to middle troposphere and the anticyclonic anomaly in middle troposphere over GD during the latter epoch, which is favorable to the increase of local dust activities. Furthermore, the decadal change of DCMD in GD is associated with the switch of Pacific Decadal Oscillation (PDO) phase. From 2000 to 2013, the PDO was in the negative phase, which induced to a positive potential height anomaly and northwesterly wind anomalies in the middle troposphere over GD. The dry and cold air brought by the anomalous northwesterly wind associated with the negative PDO phase reduces the relative humidity in the lower troposphere further amplify the effect of strengthened wind speed, being favorable for the increase of local dust loading and the resultant increase of DCMD there.
Impurity atom configurations in diamond and their visibility via scanning transmission electron microscopy imaging
Authors: Propst D , Kotakoski J , Åhlgren E H
Published: September 2023

Dispersed impurities in diamond present a flourishing platform for research in quantum informatics, spintronics and single phonon emitters. Based on the vast pool of experimental and theoretical work describing impurity atoms in diamond, we review the configurations by the chemical element discussing the relevant atomic configurations and most important properties. Dopant structures expand from single to co-doping configurations, also combined with carbon vacancies. Despite of their importance, not much is known about the exact atomic configurations associated with the dopant structures beyond computational models, partially due to difficulties in their microscopic observation. To assess the visibility of these structures, we carry out image simulations to show that the heavier dopants may be easily discernible in scanning transmission electron microscopy annular dark field images, with a window of visibility of up to over

±

10 nm in defocus. We further present the first atomic resolution images of an impurity atom configuration (substitutional Er atom) in the diamond lattice, confirmed by a comparison to the simulated images. Overall, our results demonstrate that there is a vast research field waiting for the microscopy community in resolving the exact atomic structure of various impurity atom configurations in diamond.
Association Between Optimism and Incident Stroke Among Stroke Survivors: Findings From the English Longitudinal Study of Ageing
Authors: Chilcot Joseph , Hackett Ruth A
Published: September 2023

Background

Personality has been implicated in stroke death. However, the role of personality in stroke incidence is unclear.

Purpose

Our primary aim was to investigate associations between optimism, determination, control, and the “Big Five” personality traits on incident stroke. A secondary aim was to assess the potential mediating role of health behaviors in the personality-stroke relationship.

Methods

A total of 3,703 stroke-free participants from the English Longitudinal Study of Ageing provided data on personality using the Midlife Development Inventory at Wave 5 (2010/11). Self-reported incident stroke was assessed from Waves 6 to 8 (2012–2017). Associations were modeled using discrete-time survival proportional odds logistic models. Analyses were adjusted for sociodemographic factors, history of other cardiometabolic diseases, and health behaviors.

Results

Over 6 years follow-up there were 125 incident strokes. Higher optimism (hazard ratio [HR] = 0.66; 95% confidence interval [CI] 0.53, 0.82), openness (HR = 0.72; 95% CI 0.53, 0.98), and conscientiousness (HR = 0.59; 95% CI 0.42, 0.84) were associated with reduced incident stroke risk in unadjusted models. After adjustment for sociodemographic factors and history of cardiometabolic disease, only the association between optimism and incident stroke remained significant (HR = 0.72; 95% CI 0.57, 0.92). The effect of optimism remained significant in a final model adjusting for health behaviors (HR = 0.75; 95% CI 0.60, 0.96). There was evidence of a small but significant mediating effect of physical activity.

Conclusions

Higher trait optimism was associated with reduced stroke risk. This association was partially mediated by physical activity albeit the effect was small, and caution warranted inferring causality. The interplay of personality, behavior, and clinical risk factors in stroke incidence and survivorship needs further investigation.
56 Audit of assessment, prevalence, and treatment of osteoporosis for patients attending the inflammatory bowel disease Service in Mullingar Regional Hospital
Authors: Foley M , Quirke Z , Kirca M , Moloney D
Published: September 2023

Background

Courses of steroids are common in patients with Inflammatory Bowel Disease (IBD) and are a risk factor for developing osteoporosis. Osteoporosis is a clinically silent entity and osteoporosis-related fractures are associated with chronic pain, disability, and impact quality of life. Screening of high-risk populations is the mainstay of fracture prevention. In this audit, we aimed to assess adherence to international guidelines for osteoporosis risk assessment and bone protection.

Methods

A retrospective audit was performed with a random sampling of 10% of the patients attending between October 2021 to October 2022 the IBD outpatient clinic in Mullingar Regional Hospital. Data included demographics, IBD diagnosis, FRAX tool components, FRAX score, bone health screening, DEXA results, and use of bone mineral protection. Clinical practice was compared against European Crohn’s and Colitis Organisation (ECCO) recommendations on bone protection in IBD.

Results

Of 150 charts reviewed, 39 charts were missing essential data and 8 had a diagnosis other than IBD. All 103 patients included in the analysis had received >3 months of systemic steroid use, of which 50 had a diagnosis of Crohn’s disease and 63 with ulcerative colitis. Two (2%) patients had a FRAX risk assessment for osteoporosis, and 22 (21%) had a DEXA ordered, of which 7 (7%) were by the IBD clinic. Two (2%) patients had a previous fragility fracture and 3 (3%) had been diagnosed with osteoporosis. Bone protection was used in 21 (20%) patients receiving steroids, including calcium and vitamin D supplementation (n = 19), and bisphosphonate (n = 2).

Conclusion

There are low rates of osteoporosis screening for IBD patients attending this service. There was inadequate data in the charts to calculate FRAX scores to assess osteoporosis prevalence. An intervention tool is currently being designed and the audit cycle will be completed with a repeat audit after implementation.
72 Are so-called ‘mechanical’ falls in later life as benign as we think? Data from TILDA
Authors: Keane B , McMahon G , Lavan A , Briggs R
Published: September 2023

Background

‘Mechanical’ or simple falls are those due to slips or trips, and in the absence of injury are often considered benign. Older people with ‘mechanical’ falls are often not referred for a comprehensive falls assessment. The aim of this study was to assess if ‘mechanical’ falls were a risk factor for future falls, falls-related injuries/fractures, and fear of falling.

Methods

Participants ≥65 years (n = 2,820, mean 73 years) from TILDA were included and followed from Waves 1–5 at 2-yearly intervals (8-year follow-up). ‘Mechanical’ falls were falls caused by a simple slip/trip as reported by participants. Incidence of future falls (total falls/unexplained/injurious) and fracture (hip/wrist/vertebral/other) was by self-report at each Wave. Logistic Regression models reporting odds ratios (OR) assessed the association between explained falls and future further falls/fracture and fear of falling, adjusted for relevant covariates.

Results

Over 15% (441/2,820) of participants reported ‘mechanical falls’ within the last year at Wave 1, and there was a high prevalence of established falls risk factors, e.g. polypharmacy (32%), heart disease (24%), among this cohort. ‘Mechanical’ falls were associated with a significantly increased likelihood of future injurious falls (OR 1.50 (1.21–1.870; p < 0.001)), unexplained falls (OR 1.27 (1.00–1.62); p 0.050), and fracture (OR 1.37 (1.06–1.76); p 0.015), in fully adjusted models. Reporting ≥2 ‘mechanical’ falls was independently associated with development of fear of falling (OR 1.96 (1.27–3.03); p = 0.002) and was more strongly associated with all future fall types than reporting a single ‘mechanical’ fall.

Conclusion

Older people with recent simple falls are significantly more likely to present with falls causing injury, unexplained falls, and fracture during follow-up. If simple falls are recurrent, they also have a higher likelihood of developing fear of falling. Comprehensive falls assessment, addressing established risk factors, should therefore be considered for older people with ‘mechanical’ falls, particularly if recurrent.
115 Association between muscle strength, body composition and stroke incidence- findings from the UK biobank prospective cohort study
Authors: Hayes S , Parra S , Morales C C , Forbes J , Whiston A , Pell J
Published: September 2023

Background

Stroke incidence is growing. Muscle strength and muscle mass are inversely associated with cardiovascular health and the ageing process. The aim of this study was to examine the association between components of body composition and incident stroke.

Methods

UK Biobank is a prospective, population-based study wherein 348,198 participants aged 40–69 years (56% women) were recruited. The associations of handgrip strength and muscle mass (kg) with stroke incidence over follow-up were investigated using Cox-proportional hazard models.

Results

Among 348,198 participants, 5,480 (0.02%) participants developed a fatal or non-fatal stroke event over the mean follow-up period of 8.92 (SD 1.15) years. Findings demonstrated inverse and independent associations between hand grip strength and stroke incidence (HR: 0.92, 95% CI 0.89; 0.95, p < 0.001) and stroke mortality (HR: 0.85, 95% CI 0.78; 0.92, p = 0.005) in the full-adjusted models. Findings also show inverse associations between body fat and stroke incidence (HR: 0.93, 95% CI 0.87; 0.99, p = 0.02) and stroke mortality (HR: 0.83, 95% CI 0.71; 1.00, p = 0.02). Muscle mass was not associated with stroke risk or mortality.

Conclusion

Handgrip strength and body fat were inversely associated with a higher risk of stroke among middle-aged participants in this population-based cohort study. These findings support the importance of body composition and muscle strength evaluation in screening for stroke risk among adults 40+ years old without pre-existing disease.
180 Comparative performance of a new 3-item health index in predicting mortality: a seven-year follow-up study
Authors: Knight S , Ward M , Duggan E , Xue F , Kenny R A , Romero-Ortuno R
Published: September 2023

Background

The effectiveness of health measures in predicting mortality remains a critical aspect of clinical practice. This study aimed to evaluate the performance of a novel 3-item Health Index (HI) and compare it with existing frailty measures, the Frailty Index (FI) and Frailty Phenotype (FP), for predicting all-cause mortality in a cohort of older, community-dwelling adults.

Methods

Mortality data spanning seven years, encompassing multiple confounding variables, were analysed using Cox proportional regression. The 3-item HI was developed based on resting-state systolic blood pressure sample entropy (sBP SampEn), Sustained Attention Reaction Time (SART) performance, and gait speed. Hazard Ratios (HR) and Area Under the Curve (AUC) were derived for comparative analysis.

Results

In total, there were 4,265 participants (178 deceased) in the study (mean age = 61.6 ± 8.2 years; 54% female) from The Irish Longitudinal Study on Ageing (TILDA). The new 3-item HI demonstrated superior predictive ability for all-cause mortality compared to the FI and FP, with an AUC of 0.71, surpassing the AUC values of 0.68 and 0.62 for the FI and FP, respectively. Categorising individuals into ‘Low-Risk’, ‘Medium-Risk’, and ‘High-Risk’ groups, the High-Risk group of the HI exhibited a HR of 9.14 (95% CIs: 4.21, 19.86), while the Frail group of the FI and FP displayed HRs of 4.12 (95% CIs: 2.77, 6.12) and 6.87 (95% CIs: 3.58, 13.19), respectively. Furthermore, the 3-item HI remained a significant predictor of mortality even after comprehensively adjusting for confounding variables.

Conclusion

The objectively measured new 3-item HI demonstrated superior predictive ability for all-cause mortality compared to (mostly self-reported) count-based frailty measures currently employed in clinical practice. To facilitate wider utilisation, we have developed a user-friendly MATLAB App, freely available to researchers and clinicians, allowing easy calculation of the 3-item HI in various healthcare settings. The implementation of this innovative health assessment tool could advance risk prediction and inform decision-making in patient care.
203 Secondary hyperparathyroidism is associated with poor physical performance in older adults: results from the TUDA study
Authors: Fitzpatrick D , Lannon R , Laird E , Ward M , Hoey L , Hughes C F , Strain J J , Cunningham C , McNulty H , Molloy A M , McCarroll K
Published: September 2023

Background

Vitamin D deficiency frequently leads to secondary hyperparathyroidism and is associated with frailty and sarcopenia. However, the role of hyperparathyroidism in the pathophysiology of frailty and impaired physical function is unclear. In this study, we evaluated the relationship between secondary hyperparathyroidism and poor physical performance as assessed by the Timed-Up-and-Go (TUG) test.

Methods

Participants were from a cross-sectional study of Irish adults aged >60 years. Those with eGFR <30 mL/min and serum calcium ≥2.5 mmol/L were excluded to avoid hyperparathyroidism due to renal impairment and primary hyperparathyroidism. We also excluded participants on drugs that may affect parathyroid hormone (PTH): (teriparatide, denosumab, activated forms of vitamin D), factors affecting physical function (glucocorticoid use: current or past >3 months and history of stroke) and those with an MMSE <24. Hyperparathyroidism was defined as a PTH ≥65 nmol/L and abnormal physical performance by TUG ≥12 seconds. The relationship between hyperparathyroidism and abnormal TUG was explored in logistic regression.

Results

There were 3,405 participants. 72.4% were female and mean age was 77.5 +/−7.6 years, with 36.7% having a TUG ≥12 seconds. Secondary hyperparathyroidism was significantly associated with TUG ≥12 (OR: 1.34; CI: 1.04–1.74, p = 0.026) after adjustment for age, sex, body mass index, serum 25-hydroxyvitamin D, eGFR, dairy intake, alcohol use, smoking, diabetes mellitus, cardiovascular disease (ischaemic heart disease, heart failure) and peripheral artery disease.

Conclusion

Secondary hyperparathyroidism was associated with a 34% increased risk of poor physical performance. Other research has demonstrated an association between elevated PTH and sarcopenia supporting a role for its direct effect on muscle function. This study highlights the importance of ensuring both adequate vitamin D status and calcium intake in older adults to reduce the risk of secondary hyperparathyroidism and its potential negative impact on the musculoskeletal system.
205 Exploring stakeholder experiences of Comprehensive Geriatric Assessment in community and out-patient settings: a qualitative evidence synthesis
Authors: Hayes C , Fitzgerald C , O’Shaughnessy Í , Robinson K , Galvin R
Published: September 2023

Background

Comprehensive Geriatric Assessment (CGA) is a multidimensional interdisciplinary process that addresses an older adult’s bio-psycho-social capabilities to create an integrated and co-ordinated plan of care. While there is established quantitative evidence that demonstrates the positive impacts of CGA on clinical and process outcomes, less is known about how older adults and service providers experience CGA. This study aimed to systematically review and synthesise qualitative studies reporting the experiences of CGA of community-dwelling older adults, caregivers and healthcare professionals in the community and Out-Patient Department (OPD) setting.

Methods

This qualitative evidence synthesis involved a systematic search across 5 databases targeting qualitative or mixed methods studies that reported qualitative findings on stakeholder experiences of CGA. The protocol was registered with the PROSPERO database (Registration: CRD42021283167). The methodological quality of the included studies was appraised using the Critical Appraisal Skills Programme checklist for qualitative research. Results were synthesised according to Noblit and Hare’s seven-step approach to meta-ethnography.

Results

Fourteen studies were included where CGA was completed in the home, general practice, out-patient setting in acute hospitals and in hybrid models across the community and acute OPD settings. Synthesis identified four key themes: (1) CGA is experienced as a holistic process (2) The home environment enhances CGA (3) Time, the prevailing healthcare model and interprofessional communication influenced the success of CGA in the community (4) Conflicting perspectives on the meaningful involvement of older adults, carers and family in the CGA process.

Conclusion

The findings demonstrate that CGA in a home-based setting allows for a more holistic approach to care while increasing patient satisfaction and accessibility to healthcare. Although potential barriers to the delivery of CGA include current fragmented health service structures and a lack of understanding of CGA, factors such as enhanced communication, carer and older adult involvement in the CGA process are potential facilitators to its implementation.
217 Attitudes towards Physician-Assisted Dying among medical students in an Irish medical school
Authors: Kelly E , Carthy A Mc , Oce O , O'Connell N , Briggs R , O’Donnell D
Published: September 2023

Background

Physician-Assisted Dying (PAD) is a controversial topic, particularly among medical practitioners, While PAD is currently illegal in Ireland, it has been legalised in several European countries. It is likely PAD will become an increasingly contentious issue as current medical students progress through their training and over the course of their future careers.

Methods

This project comprised of a fully anonymised survey (using the platform Qualtrics), exploring Trinity College Dublin (TCD) medical students’ attitudes towards PAD. All TCD medical students, aged 18 and above, were invited to take part in the online survey. The survey included thirteen questions, addressing student: sex, age, stage of medical training, exposure to geriatric medicine rotations, opinions on training in relation to PAD, and overall attitude to PAD. A participation information leaflet containing a link & QR code to the survey was distributed to students at lectures. An email inviting students to take part in the study was also circulated. Consent was implied by completion of the survey.

Results

200 students completed the survey. 119/200 (59.5%) of students were in favour of PAD, 53/200 (26.5%) were unsure, and 28/200 (14%) were opposed to PAD. Only 42/200 (21.%) students felt that their medical training adequately prepared them for potential discussions with patients about PAD The majority of students (31/37) who had completed rotations in Gerontology also felt that they were not adequately prepared for such discussions. 173/200 students feel that additional medical training related to PAD is warranted.

Conclusion

The majority of TCD medical students, across all genders, year of training and age groups, were in favour of PAD. Most students feel that their medical training does not prepare them for potential discussions about PAD in the future. Those who had clinical rotations in Gerontology did not feel more prepared for future discussions regarding PAD, suggesting the need for more formal teaching on the subject.
264 Improvements in associative memory and spatial navigation with acute transcutaneous Vagus Nerve Stimulation in Mild Cognitive Impairment: preliminary data
Authors: Dolphin H , Dyer A , Commins S , Finucane C , Dukelow T , Kennelly S
Published: September 2023

Background

Transcutaneous Vagus Nerve Stimulation (tVNS) is a neuromodulation technique which uses a handheld device to peripherally stimulate the afferent vagus nerve. tVNS has shown promise in augmenting memory in cognitively unimpaired populations but data in cognitively impaired populations is sparse. This investigation is timely as new therapeutic strategies to treat Mild Cognitive Impairment (MCI) are urgently needed.

Methods

VINCI-ad is an investigator-led, single-blind, sham-controlled crossover pilot study assessing the effects of tVNS in amnestic MCI. All participants have MCI (Clinical-Dementia Rating Scale—Global Score of 0.5) with amnestic neuropsychological profile (RBANS delayed memory index <85). Participants are randomised over 3 study visits to baseline (no stimulation) active stimulation (at the CC of left ear) or sham stimulation (earlobe). Cognitive tests include Face-Name Association Task (FNAT), Sustained Attention Response Test (SART) and Sea Hero Quest Navigation Test (SHQ) among others.

Results

Interim data analysis of 28 participants (planned recruitment n = 40) is presented (mean age 71.5 (range 55–85), 17 male, RBANS DMI 73.3 ± 11.1). CSF ad biomarkers were positive for 75% (21/28) (AB-42460.4 pg/ml (± 83.3 pg/ml) and p-tau181 82.5 pg/ml [± 53.2 pg/ml]) and 78% (22/28) of participants had a Charleston Comorbidity Index of ≥3. Mean tVNS stimulation time pre-cognitive assessments was 21.2 minutes, with mean amplitude setting during active stimulation of 2.5 mA (1.8–4.5) and sham of 2.0 mA (0.9–3.1). During FNAT, active tVNS had no effect on facial recognition or reaction times, however recall accuracy was significantly improved (69.2% ±3.13) compared to baseline (44.7% ±3.51 p = 0.016) and sham (50.1% ±3.28 p = 0.021) and during active tVNS spatial navigation (38.94 sec [±1.68]) was quicker than baseline (51.49 sec (±3.2) p = 0.0164) and sham (51.9 sec (±3.15) p = 0 0.0038). We noted no significant improvements in SART or other cognitive tests performance during tVNS.

Conclusion

tVNS may be a useful complementary tool to augment spatial and associative memory in MCI. Further larger studies are needed to delineate precise settings in this population.
273 Improving frail care—is there a role for the geriatrician in elective waiting lists?
Authors: James K , Soppitt D , Davies E , Burberry D
Published: September 2023

Background

The perfect storm of an ageing population and recent pandemic has hugely impacted waiting lists. There is evidence for frailty assessment at point of referral as per the traditional Peri-Operative Care of Older People undergoing Surgery (POPS) model however our concern was for all those patients already on lengthy waiting lists. We obtained funding via the Bevan commission to look at whether a geriatrician had a role in reviewing need for surgery, intervening in medical issues and the best way to select the patients who would benefit.

Methods

We chose the cholecystectomy list to start as the ‘least frail’. We contacted all patients completing a modified CRANE (Comprehensive Risk Assessment and Needs Evaluation) questionnaire and frailty scoring. We offered a clinic appointment to any patient with a CFS (Clinical Frailty Score) over 4 or who triggered for frailty. Primary outcome was patients removed from the list, secondary outcomes included cost savings through avoiding further outpatient tests and consults, diagnoses made and patient feedback collected.

Results

Over 20% of patients were removed from the waiting list with a cost saving of around £250,000. 54 patients were offered clinic appointments, over 25 tests were ordered minimising delays in pre-operative assessment and diagnoses including dementia and hyponatraemia were made. Patient feedback was excellent. They felt there was an improvement in the health and social care needs being met following an outpatient appointment and raised the importance of good communication whilst waiting a procedure. The HFRS (Hospital Frailty Risk Score) showed the greatest specificity in selecting patients for clinic while the CRANE questionnaire was more sensitive.

Conclusion

Clearly geriatricians have a huge role to play in perioperative medicine. We have suggested a modified POPS model with a six monthly CFS score and CRANE questionnaire to identify patients who are becoming frailer while waiting. The project shows cost savings and decreased waits but more importantly improvement in patient care and satisfaction.
286 Gait speed—a useful addition to dementia risk prediction in midlife? Results from ENBIND
Authors: Morrison L , Dyer A , Kennelly S
Published: September 2023

Background

Midlife Type 2 Diabetes (T2DM) is associated with a two-fold increased risk of dementia in later life. The utility of spatiotemporal gait characteristics to identify those with midlife T2DM at greatest risk of later cognitive decline has not been assessed. This may aid in selecting-out those at greatest risk for preventative brain-health interventions.

Methods

ENBIND is a longitudinal study of cognitively-healthy individuals with midlife T2DM (free from microvascular/macrovascular complications) and healthy controls. At baseline, gait speed was measured across three tasks (usual gait speed, maximal gait speed and cognitive dual-task—whilst reciting alternate letters of the alphabet). Domain-specific neuropsychological performance was assessed using the Montreal Cognitive Assessment (MoCA) and a custom CANTAB battery with identical assessments repeated at a 4-year interval. Linear regression was used to analyse results with adjustment for important clinical confounders.

Results

30 individuals (aged 55.5 ± 9 years; 50% female) were followed up, of whom three-quarters (n = 23, 76.7%) had midlife T2DM. Individuals with midlife T2DM did not experience greater cognitive decline over 4 years. Slower ‘usual’ gait speed (but not dual-task or maximal speed) at baseline was associated with greater likelihood of incident errors on the MoCA at 4 years, which persisted on controlling for T2DM status, age, sex and baseline cognition (B: -0.22 [95% Confidence Interval: −0.41, −0.03, p = 0.03]). Slower maximal (B: −3.07, −6.06, −0.08, p = 0.04) and cognitive dual-task (B:-1.98, −3.61, −0.17, p = 0.03) speed were both associated with significantly poorer delayed memory performance after 4 years.

Conclusion

In middle-aged individuals with known dementia risk factors, gait speed may be a useful adjunct to identify those at greatest risk of longitudinal cognitive decline. Whilst usual gait speed was associated with a decline in global cognition, fast and dual task gait speed were associated with longitudinal decline in delayed memory performance.
322 Implantable Loop Recorders in unexplained falls
Authors: Bourke R , Perez S , Leenders M , Maree A , Melis M , Foran T , Kenny R A
Published: September 2023

Background

Falls are the most common cause of injury in older adults leading to hospitalisation, functional decline, and increased morbidity and mortality. Cardiac arrhythmia is a known risk factor for falls with arrhythmias implicated as causative in up to 20% of unexplained falls in older adults. The aim was to examine arrhythmia and activity data in older fallers using an Implantable Loop Recorder (ILR) with an embedded accelerometer (Medtronic reveal LINQ).

Methods

Thirty participants with at least two falls in the previous two years were prospectively recruited. All met criteria for ILR insertion following a comprehensive cardiovascular assessment, where no abnormalities were detected. Cardiac and accelerometer data were collected for 1 year. Falls details were collected using falls diaries.

Results

The mean age of participants was 68.0 years (±9.3). 19/30 (63.3%) were female. 22/30 (73.3%) had at least one cardiovascular condition documented in their medical history. Sixteen participants (53%) had a significant arrhythmia during follow up with mean time to arrhythmia 101.6 days. Arrhythmias included tachyarrhythmias, bradyarrhythmia (with asystole) and atrial fibrillation. Five (17%) required pacemaker insertion. Combining nocturnal and diurnal cardiac parameters with accelerometer data were not predictive of falls.

Conclusion

ILRs are useful tools to help identify the cause of unexplained falls. The paroxysmal nature of arrhythmia make diagnosis without prolonged monitoring difficult, given that all participants had thorough cardiovascular investigations prior to implantation. This research supports European Society of Cardiology and World Falls guidelines for implantation of ILR in older people with unexplained falls. The addition of a triaxial accelerometer did not demonstrate added value in falls prediction.