A lack of association between BMI and chemoimmunotherapy efficacy in advanced non-small cell lung cancer: Secondary analysis of the IMpower150 and IMpower130 clinical trials.

BACKGROUND: Multiple studies have indicated that patients with high body mass index (BMI) may have favourable survival outcomes following treatment with an immune checkpoint inhibitor (ICI). However, this evidence is limited by several factors, notably the minimal evidence from randomised controlled trials (RCTs), the use of categorised BMI with inconsistent cut point definitions, and minimal investigation of contemporary combination ICI therapy. Moreover, whether overweight and obese patients gain a larger benefit from contemporary frontline chemoimmunotherapy in non-small cell lung cancer (NSCLC) is unclear. METHODS: This secondary analysis pooled individual patient data from the intention-to-treat population of the IMpower130 and IMpower150 RCTs comparing chemoimmunotherapy versus chemotherapy. Co-primary outcomes were overall survival (OS) and progression-free survival (PFS). The potentially non-linear relationship between BMI and chemoimmunotherapy treatment effect was evaluated using Multivariable Fractional Polynomial Interaction (MFPI). As a sensitivity analysis, chemoimmunotherapy treatment effect (chemoimmunotherapy versus chemotherapy) on survival was also estimated for each BMI subgroup defined by World Health Organisation classification. Exploratory analyses in the respective chemoimmunotherapy and chemotherapy cohort were undertaken to examine the survival outcomes among BMI subgroups. RESULTS: A total of 1282 patients were included. From the MFPI analysis, BMI was not significantly associated with chemoimmunotherapy treatment effect with respect to either OS (p = 0.71) or PFS (p = 0.35). This was supported by the sensitivity analyses that demonstrated no significant treatment effect improvement in OS/PFS among overweight or obese patients compared to normal weight patients (OS: normal BMI HR = 0.74 95% CI 0.59-0.93, overweight HR = 0.78 95% CI 0.61-1.01, obese HR = 0.84 95% CI 0.59-1.20). Exploratory analyses further highlighted that survival outcomes were not significantly different across BMI subgroups in either the chemoimmunotherapy therapy cohort (Median OS: normal BMI 19.9 months, overweight 17.9 months, and obese 19.5 months, p = 0.7) or the chemotherapy cohort (Median OS: normal 14.1 months, overweight 15.9 months, and obese 16.7 months, p = 0.7). CONCLUSION: There was no association between high BMI (overweight or obese individuals) and enhanced chemoimmunotherapy treatment benefit in front-line treatment of advanced non-squamous NSCLC. This contrasts with previous publications that showed a superior treatment benefit in overweight and obese patients treated with immunotherapy given without chemotherapy.

N-of-1 Trials of Antimicrobial Stewardship Interventions to Optimize Antibiotic Prescribing for Upper Respiratory Tract Infection in Emergency Departments: Protocol for a Quasi-Experimental Study.

BACKGROUND: Antimicrobial stewardship programs attempting to optimize antibiotic therapy and clinical outcomes mainly focus on inpatient and outpatient settings. The lack of antimicrobial stewardship program studies in the emergency department (ED) represents a gap in tackling the problem of antimicrobial resistance as EDs treat a substantial number of upper respiratory tract infection cases throughout the year. OBJECTIVE: We intend to implement two evidence-based interventions: (1) patient education and (2) providing physician feedback on their prescribing rates. We will incorporate evidence from a literature review and contextualizing the interventions based on findings from a local qualitative study. METHODS: Our study uses a quasi-experimental design to evaluate the effects of interventions over time in the EDs of 4 public hospitals in Singapore. We will include an initial control period of 18 months. In the next 6 months, we will randomize 2 EDs to receive 1 intervention (ie, patient education) and the other 2 EDs to receive the alternative intervention (ie, physician feedback). All EDs will receive the second intervention in the subsequent 6 months on top of the ongoing intervention. Data will be collected for another 6 months to assess the persistence of the intervention effects. The information leaflets will be handed to patients at the EDs before they consult with the physician, while feedback to individual physicians by senior doctors is in the form of electronic text messages. The feedback will contain the physicians' antibiotic prescribing rate compared with the departments' overall antibiotic prescribing rate and a bite-size message on good antibiotic prescribing practices. RESULTS: We will analyze the data using segmented regression with difference-in-difference estimation to account for concurrent cluster comparisons. CONCLUSIONS: Our proposed study assesses the effectiveness of evidence-based, context-specific interventions to optimize antibiotic prescribing in EDs. These interventions are aligned with Singapore's national effort to tackle antimicrobial resistance and can be scaled up if successful. TRIAL REGISTRATION: ClinicalTrials.gov NCT05451863; https://clinicaltrials.gov/study/NCT05451836. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/50417.

Applying Andersen's healthcare utilization model to assess factors influencing patients' expectations for diagnostic tests at emergency department visits during the COVID-19 pandemic.

Background: The uncertainties surrounding the COVID-19 pandemic led to a surge in non-urgent emergency department (ED) attendance among people presenting with upper respiratory tract infection (URTI) symptoms. These non-urgent visits, often manageable in primary care, exacerbated ED overcrowding, which could compromise the quality of ED services. Understanding patients' expectations and the reasons for these ED visits is imperative to mitigate the problem of ED overcrowding. Hence, we assessed the factors influencing patients' expectations for diagnostic tests during their ED visits for uncomplicated URTI during different phases of the pandemic. Methods: We conducted a cross-sectional study on adults with URTI symptoms seeking care at four public EDs in Singapore between March 2021 and March 2022. We segmented the study period into three COVID-19 pandemic phases-containment, transition, and mitigation. The outcome variables are whether patients expected (1) a COVID-19-specific diagnostic test, (2) a non-COVID-19-specific diagnostic test, (3) both COVID-19-specific and non-COVID-19-specific diagnostic tests, or (4) no diagnostic test. We built a multinomial regression model with backward stepwise selection and classified the findings according to Andersen's healthcare utilization model. Results: The mean age of participants was 34.5 (12.7) years. Factors (adjusted odds ratio [95% confidence interval]) influencing expectations for a COVID-19-specific diagnostic test in the ED include younger age {21-40 years: (2.98 [1.04-8.55])}, no prior clinical consultation (2.10 [1.13-3.89]), adherence to employer's health policy (3.70 [1.79-7.67]), perceived non-severity of illness (2.50 [1.39-4.55]), being worried about contracting COVID-19 (2.29 [1.11-4.69]), and during the transition phase of the pandemic (2.29 [1.15-4.56]). Being non-employed influenced the expectation for non-COVID-19-specific diagnostic tests (3.83 [1.26-11.66]). Factors influencing expectations for both COVID-19-specific and non-COVID-19-specific tests include younger age {21-40 years: (3.61 [1.26-10.38]); 41-60 years: (4.49 [1.43-14.13])}, adherence to employer's health policy (2.94 [1.41-6.14]), being worried about contracting COVID-19 (2.95 [1.45- 5.99]), and during the transition (2.03 [1.02-4.06]) and mitigation (2.02 [1.03-3.97]) phases of the pandemic. Conclusion: Patients' expectations for diagnostic tests during ED visits for uncomplicated URTI were dynamic across the COVID-19 pandemic phases. Expectations for COVID-19-specific diagnostic tests for ED visits for uncomplicated URTI were higher among younger individuals and those worried about contracting COVID-19 during the COVID-19 pandemic. Future studies are required to enhance public communications on the availability of diagnostic services in primary care and public education on self-management of emerging infectious diseases such as COVID-19.

Betting on Australian Rules Football: Can Expert Tipsters beat Randomness?

Betting on the various codes of football in Australia accounts for the majority of sports betting, with Australian rules football (AFL) by far the most popular sport in Australia. Several studies have revealed the heavy presence of gambling advertising during AFL broadcasts, and a frequently used advertising strategy involves the use of well-known AFL commentators outlining their tips and betting suggestions. To date, no research has examined the hypotheses that skill may help in predicting AFL matches and monetary outcomes from AFL betting. Rather than merely discounting such ideas, it is important to test them empirically. The aims of this study were therefore, to examine if (1) expert AFL tipsters made better predictions than random picks, (2) expert AFL tipsters gained greater monetary reward than random selection, and (3) expert tipsters' prediction accuracy improved with betting experience. To this end, six seasons of AFL matches, odds data, and expert tipster data were analysed retrospectively, totalling 1141 matches. Random selections were calculated for each match using an inbuilt random number generator within Microsoft Excel and a $2 simulated wager was applied for each AFL match. The results of mixed-effects modelling showed that experts picked more correct outcomes than random selection; experts' correct predictions were partially mediated by home-game selections; no difference in monetary outcome was observed for experts compared to random selection; experts' predictions did not improve over time. The results of this study may be used to inform both psychological interventions that target gamblers' illusions of control, and public health gambling harm prevention messaging.

Low Risk of Hyperprogression with First-Line Chemoimmunotherapy for Advanced Non-Small Cell Lung Cancer: Pooled Analysis of 7 Clinical Trials.

BACKGROUND: Monotherapy immune checkpoint inhibitor (ICI) used in second- or later-line settings has been reported to induce hyperprogression. This study evaluated hyperprogression risk with ICI (atezolizumab) in the first-, second-, or later-line treatment of advanced non-small cell lung cancer (NSCLC), and provides insights into hyperprogression risk with contemporary first-line ICI treatment. METHODS: Hyperprogression was identified using Response Evaluation Criteria in Solid Tumours (RECIST)-based criteria in a dataset of pooled individual-participant level data from BIRCH, FIR, IMpower130, IMpower131, IMpower150, OAK, and POPLAR trials. Odds ratios were computed to compare hyperprogression risks between groups. Landmark Cox proportional-hazard regression was used to evaluate the association between hyperprogression and progression-free survival/overall survival. Secondarily, putative risk factors for hyperprogression among second- or later-line atezolizumab-treated patients were evaluated using univariate logistic regression models. RESULTS: Of the included 4644 patients, 119 of the atezolizumab-treated patients (n = 3129) experienced hyperprogression. Hyperprogression risk was markedly lower with first-line atezolizumab-either chemoimmunotherapy or monotherapy-compared to second/later-line atezolizumab monotherapy (0.7% vs. 8.8%, OR = 0.07, 95% CI, 0.04-0.13). Further, there was no statistically significant difference in hyperprogression risk with first-line atezolizumab-chemoimmunotherapy versus chemotherapy alone (0.6% vs. 1.0%, OR = 0.55, 95% CI, 0.22-1.36). Sensitivity analyses using an extended RECIST-based criteria including early death supported these findings. Hyperprogression was associated with worsened overall survival (HR = 3.4, 95% CI, 2.7-4.2, P < .001); elevated neutrophil-to-lymphocyte ratio was the strongest risk factor for hyperprogression (C-statistic = 0.62, P < .001). CONCLUSIONS: This study presents first evidence for a markedly lower hyperprogression risk in advanced NSCLC patients treated with first-line ICI, particularly with chemoimmunotherapy, as compared to second- or later-line ICI treatment.

A multi-institutional exploration of emergency medicine physicians' attitudes and behaviours on antibiotic use during the COVID-19 pandemic: a mixed-methods study.

BACKGROUND: The COVID-19 pandemic has changed the epidemiology of upper respiratory tract infections (URTI) and the disease profile of patients attending the emergency department (ED). Hence, we sought to explore the changes in ED physicians' attitudes and behaviours in four EDs in Singapore. METHODS: We employed a sequential mixed-methods approach (quantitative survey followed by in-depth interviews). Principal component analysis was performed to derive latent factors, followed by multivariable logistic regression to explore the independent factors associated with high antibiotic prescribing. Interviews were analysed using the deductive-inductive-deductive framework. We derive five meta-inferences by integrating the quantitative and qualitative findings with an explanatory bidirectional framework. RESULTS: We obtained 560 (65.9%) valid responses from the survey and interviewed 50 physicians from various work experiences. ED physicians were twice as likely to report high antibiotic prescribing rates pre-COVID-19 pandemic than during the pandemic (AOR = 2.12, 95% CI 1.32 to 3.41, p = 0.002). Five meta-inferences were made by integrating the data: (1) Less pressure to prescribe antibiotics due to reduced patient demand and more patient education opportunities; (2) A higher proportion of ED physicians self-reported lower antibiotic prescribing rates during the COVID-19 pandemic but their perception of the overall outlook on antibiotic prescribing rates varied; (3) Physicians who were high antibiotic prescribers during the COVID-19 pandemic made less effort for prudent antibiotic prescribing as they were less concerned about antimicrobial resistance; (4) the COVID-19 pandemic did not change the factors that lowered the threshold for antibiotic prescribing; (5) the COVID-19 pandemic did not change the perception that the public's knowledge of antibiotics is poor. CONCLUSIONS: Self-reported antibiotic prescribing rates decreased in the ED during the COVID-19 pandemic due to less pressure to prescribe antibiotics. The lessons and experiences learnt from the COVID-19 pandemic can be incorporated into public and medical education in the war against antimicrobial resistance going forward. Antibiotic use should also be monitored post-pandemic to assess if the changes are sustained.

Antibiotic expectation, behaviour, and receipt among patients presenting to emergency departments with uncomplicated upper respiratory tract infection during the COVID-19 pandemic.

OBJECTIVES: Pre-COVID-19 pandemic, patients who attended the emergency department (ED) for upper respiratory tract infection (URTI) were more likely to receive antibiotics if they expected them. These expectations could have changed with the change in health-seeking behaviour during the pandemic. We assessed the factors associated with antibiotics expectation and receipt for uncomplicated URTI patients in four Singapore EDs during the COVID-19 pandemic. METHODS: We conducted a cross-sectional study on adult patients with URTI from March 2021 to March 2022 in four Singapore EDs and assessed the determinants of antibiotics expectation and receipt using multivariable logistic regression models. We also assessed the reasons patients expect antibiotics during their ED visit. RESULTS: Among 681 patients, 31.0% expected antibiotics while 8.7% received antibiotics during their ED visit. Factors (adjusted odds ratio [95% confidence interval]) that significantly influenced expectation for antibiotics include: 1) prior consultation for current illness with (6.56 [3.30-13.11]) or without (1.50 [1.01-2.23]) antibiotics prescribed; 2) anticipation for COVID-19 test (1.56 [1.01-2.41]); and 3) poor (2.16 [1.26-3.68]) to moderate (2.26 [1.33-3.84]) knowledge on antibiotics use and resistance. Patients expecting antibiotics were 10.6 times (10.64 [5.34-21.17]) more likely to receive antibiotics. Those with tertiary education were twice (2.20 [1.09-4.43]) as likely to receive antibiotics. CONCLUSION: In conclusion, patients with URTI who expected antibiotics to be prescribed remained more likely to receive it during the COVID-19 pandemic. This highlights the need for more public education on the non-necessity for antibiotics for URTI and COVID-19 to address the problem of antibiotic resistance.

Blastocystis occurrence in water sources worldwide from 2005 to 2022: a review.

There has been increasing interest in the study of Blastocystis in the last two decades. Many studies have been carried out in human and animal hosts including environmental sources, but there is little or no information on the occurrence of Blastocystis in water sources worldwide. Therefore, this study aimed at assessing the occurrence of Blastocystis in water sources across the world from 2005 to 2022, noting the method of detection and the distribution of the subtypes from various water sources. A literature search was performed on internet-based databases including Google search, PubMed, Scopus, and Web of Science. Upon application of the criteria for inclusion, 25 articles revealing the occurrence of Blastocystis in water sources in 15 countries were included in the review. Blastocystis occurrence varies across water sources ranging from 0% in a drinking water source in Venezuela to 100% in rivers; well water, stored water, and fishpond in Nepal and Malaysia; and fountain water, irrigation water, and rainwater in Italy, Spain, and Thailand. The occurrence of the parasite was significantly associated with the coliform count, temperature, conductivity, dissolved oxygen, turbidity, total dissolved solids, and chemical oxygen demand. A total of 11 Blastocystis subtypes were identified in water sources worldwide, namely, ST1-ST8, ST10, ST23, and ST26 in which ST1 and ST3 were the most prevalent subtypes. Considering the importance of Blastocystis as a waterborne parasite, the subtype distribution and morphological distinction in water sources need to be carried out using molecular and electron microscopic techniques. Existing studies have covered only about 10% of the world's countries.

Positive Orientation and Psychological Distress: An Examination with Psychiatric Outpatients

@#Introduction: This research was conducted to extend the theoretical construct of positive orientation (PO) to psychiatric outpatients. This research also examined the effect of PO on alleviating stress, anxiety, and depression among psychiatric outpatients. Methods: This cross-sectional survey recruited 301 psychiatric outpatients online. As these respondents have a short attention span, short measures were used to measure PO-related variables (life satisfaction, optimism, self-esteem) and indicators of psychological distress (depression, anxiety, and stress). These outpatients are at the legal age to provide consent for themselves (M = 30.12, SD= 8.11). The majority of them have been identified as male (80.07%). Similarly, the ethnic distribution was unequal, with the majority of these outpatients identified as Malay (85.05%), followed by those who were identified as Chinese (7.31%), Indian (4.32%), and from other ethnic groups (3.32%). Results: Generalized structured component analysis (GSCA) supported that satisfaction with life, optimism, and self-esteem reflect the construct of PO. Furthermore, PO predicted depression, anxiety, and depression negatively. Conclusion: It is possible to replicate the construct of PO with psychiatric outpatients using single item measures for life satisfaction, optimism, and self-esteem. PO is beneficial to psychiatric outpatients as it reduces the severity of depression, anxiety, and stress.

Eating self-regulatory skill, diet quantity, and diet quality of Malaysian healthcare university students: A cross-sectional study

@#Introduction: The ability to self-regulate eating can improve health. This study aimed to determine the relationship between eating self-regulatory skills, diet quantity, and diet quality among Malaysian university students. Methods: This cross-sectional study involved 132 university students. Eating self-regulatory skill was assessed using the Self-Regulation of Eating Behaviour Questionnaire (SREBQ). Dietary intakes from two 24-hour dietary recalls were used to assess diet quantity and quality. Diet quantity was measured as energy and macronutrient intakes, analysed using NutritionistPro. Diet quality was measured using the Malaysian Healthy Eating Index (M-HEI). The relationship between eating self-regulatory skills, diet quantity, and diet quality were evaluated using tests for differences between means and multiple linear regression. Results: Male participants (n=47) consumed more energy than female participants (n=85) (Male: 1850±570 kcal/day, Female: 1596±567 kcal/day, p=0.015). Participants from the Nutrition and Dietetics (N&D) course (n=49) had better M-HEI scores than participants from other health courses (n=83) (N&D course: 52.7±10.5, non-N&D course: 47.2±10.7, p=0.005). The predictors of energy intake were gender (β=-0.193, p=0.023) and SREBQ score (β=- 0.223, p=0.009). Being female and having higher eating self-regulatory skills were associated with lower energy intake. The predictors of diet quality were university course (β=0.240, p=0.005) and SREBQ score (β=0.181, p=0.033). Studying N&D and having higher eating self-regulatory skills were associated with higher M-HEI scores. Conclusion: Higher self-regulation of eating behaviour score is a factor that contributes to lower daily energy intake and higher diet quality score.

Detection of hospital environmental contamination during SARS-CoV-2 Omicron predominance using a highly sensitive air sampling device.

Background and objectives: The high transmissibility of SARS-CoV-2 has exposed weaknesses in our infection control and detection measures, particularly in healthcare settings. Aerial sampling has evolved from passive impact filters to active sampling using negative pressure to expose culture substrate for virus detection. We evaluated the effectiveness of an active air sampling device as a potential surveillance system in detecting hospital pathogens, for augmenting containment measures to prevent nosocomial transmission, using SARS-CoV-2 as a surrogate. Methods: We conducted air sampling in a hospital environment using the AerosolSenseTM air sampling device and compared it with surface swabs for their capacity to detect SARS-CoV-2. Results: When combined with RT-qPCR detection, we found the device provided consistent SARS-CoV-2 detection, compared to surface sampling, in as little as 2 h of sampling time. The device also showed that it can identify minute quantities of SARS-CoV-2 in designated "clean areas" and through a N95 mask, indicating good surveillance capacity and sensitivity of the device in hospital settings. Conclusion: Active air sampling was shown to be a sensitive surveillance system in healthcare settings. Findings from this study can also be applied in an organism agnostic manner for surveillance in the hospital, improving our ability to contain and prevent nosocomial outbreaks.

Safety and Immunogenicity of ChAd63/MVA Pfs25-IMX313 in a Phase I First-in-Human Trial.

Background: Transmission blocking vaccines targeting the sexual-stages of the malaria parasite could play a major role to achieve elimination and eradication of malaria. The Plasmodium falciparum Pfs25 protein (Pfs25) is the most clinically advanced candidate sexual-stage antigen. IMX313, a complement inhibitor C4b-binding protein that forms heptamers with the antigen fused to it, improve antibody responses. This is the first time that viral vectors have been used to induce antibodies in humans against an antigen that is expressed only in the mosquito vector. Methods: Clinical trial looking at safety and immunogenicity of two recombinant viral vectored vaccines encoding Pfs25-IMX313 in healthy malaria-naive adults. Replication-deficient chimpanzee adenovirus serotype 63 (ChAd63) and the attenuated orthopoxvirus modified vaccinia virus Ankara (MVA), encoding Pfs25-IMX313, were delivered by the intramuscular route in a heterologous prime-boost regimen using an 8-week interval. Safety data and samples for immunogenicity assays were taken at various time-points. Results: The reactogenicity of the vaccines was similar to that seen in previous trials using the same viral vectors encoding other antigens. The vaccines were immunogenic and induced both antibody and T cell responses against Pfs25, but significant transmission reducing activity (TRA) was not observed in most volunteers by standard membrane feeding assay. Conclusion: Both vaccines were well tolerated and demonstrated a favorable safety profile in malaria-naive adults. However, the transmission reducing activity of the antibodies generated were weak, suggesting the need for an alternative vaccine formulation. Trial Registration: Clinicaltrials.gov NCT02532049.

Droplet rolling angle model of micro-nanostructure superhydrophobic coating surface.

The droplet rolling angle is one of the important indicators to measure the coating's hydrophobic performance, but the specific factors affecting the droplet rolling angle on the micro-nanostructured superhydrophobic coating surface are not yet known. Based on the rolling mechanism of droplets on rough surfaces, and from the perspective of coating microscopic energy conservation, this paper points out that the micron-scale morphology and the nanoscale morphology can comprehensively affect the droplet rolling angle. From the above perspective, a mathematical model of the droplet rolling angle on the micro-nanostructure superhydrophobic coating surface was established. The model shows that the droplet rolling angle is positively correlated with the ratio of nano-sized pillar width to spacing, the ratio of micron-sized papilla radius to spacing, and the liquid-gas interfacial tension, and is negatively correlated to the droplet intrinsic contact angle, droplet volume and droplet density. The droplet rolling angle calculated by the presented model is in good agreement with the experimentally tested results. This model can provide good accuracy in predicting the droplet rolling angle on the micro-nanostructured superhydrophobic coating surface.

Examination of barnacles' potential to be used as bioindicators of persistent organic pollutants in coastal ecosystem: A Malaysia case study.

Barnacles are ubiquitous in coastal ecosystems of different geographical regions worldwide. This is the first study attempting to assess the suitability of barnacles as bioindicators of persistent organic pollutants (POPs) in coastal environments. Barnacles were collected from the coasts around Peninsular Malaysia and analyzed for POPs including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs). Among POPs, PCBs showed the highest concentrations with elevated contributions of CB28 and CB153. As for PBDEs, BDE47 was the most frequently detected congener, while BDE209 was detected in barnacles from two stations in Port Klang and the levels reached up to >70% of total PBDE concentrations. Concentrations of OCPs detected in barnacles were in the order of CHLs > DDTs > HCHs > HCB and 4,4'-DDE and cis- and trans-chlordane were the predominant OCP compounds. A comparison with previous studies in Malaysia showed consistent levels of POPs. Green mussels collected from selected barnacles' habitats, for the sake of a comparison, showed almost similar profiles but lower concentrations of POPs. The spatial distribution of POPs observed in barnacles and comparison of POP levels and profiles with mussels indicated that barnacles can be useful bioindicators for monitoring POPs contamination in the coastal ecosystems.

Artificial intelligence for teleophthalmology-based diabetic retinopathy screening in a national programme: an economic analysis modelling study.

BACKGROUND: Deep learning is a novel machine learning technique that has been shown to be as effective as human graders in detecting diabetic retinopathy from fundus photographs. We used a cost-minimisation analysis to evaluate the potential savings of two deep learning approaches as compared with the current human assessment: a semi-automated deep learning model as a triage filter before secondary human assessment; and a fully automated deep learning model without human assessment. METHODS: In this economic analysis modelling study, using 39 006 consecutive patients with diabetes in a national diabetic retinopathy screening programme in Singapore in 2015, we used a decision tree model and TreeAge Pro to compare the actual cost of screening this cohort with human graders against the simulated cost for semi-automated and fully automated screening models. Model parameters included diabetic retinopathy prevalence rates, diabetic retinopathy screening costs under each screening model, cost of medical consultation, and diagnostic performance (ie, sensitivity and specificity). The primary outcome was total cost for each screening model. Deterministic sensitivity analyses were done to gauge the sensitivity of the results to key model assumptions. FINDINGS: From the health system perspective, the semi-automated screening model was the least expensive of the three models, at US$62 per patient per year. The fully automated model was $66 per patient per year, and the human assessment model was $77 per patient per year. The savings to the Singapore health system associated with switching to the semi-automated model are estimated to be $489 000, which is roughly 20% of the current annual screening cost. By 2050, Singapore is projected to have 1 million people with diabetes; at this time, the estimated annual savings would be $15 million. INTERPRETATION: This study provides a strong economic rationale for using deep learning systems as an assistive tool to screen for diabetic retinopathy. FUNDING: Ministry of Health, Singapore.

Dust contamination on surface of transmission line insulators in air-polluted regions in China: statistical characteristics, adhesion mechanism, and environmental impact factors.

Dust particles suspended in the atmosphere have been a big headache for electric power transmission industry in China. As transmission lines pass through dusty or air-polluted areas, dust contaminants are likely to deposit and accumulate on line insulators, which is one of the greatest causes of flashover and failure of power transmission. To study the statistical characteristics of this type of contamination, dust samples were collected and measured, and a physical model was set up to explain the deposition and accumulation mechanism of the particles. The trajectories of particles were tracked using fluid mechanics and contact mechanics, and an adhesion criterion was proposed. Simulation software was then applied to validate the model; further different environmental factors were studied that would affect the particle size distribution. The results show that under natural contamination conditions, the particle size distribution on the surface of the insulator shows a certain concentration at size ranges 1~100 µm and basically obeys a log-normal distribution. In addition, relative humidity, air velocity, and the charge accumulated on the surface all have significant influences on particle size distribution characteristics, while the effect of the electric field is mainly reflected in the difference in the number concentration of particle adhesion.