Browse Articles

Physiological growth of ocular axial length among Chinese children and teenagers: A 6-year cohort study

To investigate the pattern and threshold of physiological growth, defining as axial length (AL) elongation that results in little refraction progression, among Chinese children and teenagers, a total of 916 children aged between 7 and 18 years from a 6-year longitudinal cohort study were included for analysis. Ocular biometry, cycloplegic refraction and demographic data were obtained annually. Physiological growth was calculated based on myopic progression and Gullstrand eye model, respectively. The annual change in AL was found to be significantly smaller in the persistent emmetropia (PE) group compared to the incident myopia (IM) and persistent myopia (PM) group at all ages (all P < 0.05). In children with non-progressive myopia, there was observed axial elongation ranging from 0.17 to 0.23 mm/year between the ages of 9 and 12. This growth rate persisted at approximately 0.10 mm/year beyond the age of 12. While the compensated AL growth calculated using Gullstrand model was only 0.02 to 0.15 mm/year at age of 9–12, and decreased to around 0 mm/year after age of 12. For children aged 7–9 years, the cutoff point for AL growth to distinguish between progressive myopia and non-progressive myopia was 0.19 mm/year. These findings indicate a notable disparity between the thresholds of physiological growth calculated using myopic progression and Gullstrand eye model. This observation suggests that when formulating effective myopia control strategies, consideration should be given to different calculation methods when applying physiological AL growth as a starting point or target.

Study on the evolution of the spatial patterns and driving factors of national agricultural cultural heritage in China

The study analyzed the spatial distribution characteristics, evolution rules, and driving factors of 138 China’s national agricultural cultural heritage sites from 2013 to 2021 at the overall and regional levels, using kernel density analysis, Centres for standard deviation ellipse analyses, spatial autocorrelation analysis, and geographical detector analysis.The results showed that: ①From an overall perspective, the spatial pattern of China’s national agricultural cultural heritage changed greatly from 2013 to 2021, with a highly uneven spatial distribution, gradually showing a distribution pattern of "widely distributed, locally concentrated". The spatial distribution of China’s national agricultural cultural heritage is increasingly evident, and the spatial distribution type has evolved from discrete to clustered. The spatial distribution center of gravity shows a shift trajectory of "north-east, then south-east". During the study period, the X axis of the standard deviation ellipse was always greater than the Y axis, but the difference between the X and Y axes was small, indicating that the spatial distribution direction was northeast-southwest, but the directionality was weak. The types of national agricultural cultural heritage are diverse and rich, involving farmland landscapes, composite systems, crop varieties, vegetables and melons, tea, forest fruits, special products, farmland irrigation, and animal breeding, in which forest and fruit class heritage site dominate. ②From a regional perspective, the spatial distribution of China’s national agricultural cultural heritage varies greatly, with strong national and regional characteristics. The high-density core area of the national agricultural cultural heritage in 2013 was located in the intersection of Fujian, Zhejiang and Jiangxi. After 2017, the high-density core area moved northward to the Yangtze River Delta region, which was caused by a combination of economic, cultural, and geographical factors. In addition, the agglomeration of the intersection edge area of Guizhou, Hunan and Yunnan provinces has emerged in 2021. In analyzing spatial autocorrelation, drawing on existing relevant research results, the study selected county-level administrative districts as the research unit. The analysis results show that there is a positive spatial correlation between China’s national agricultural cultural heritage sites in 2017 and beyond, with the spatial distribution types mainly being LL and LH. During the study period, the number of LL and HH type areas has been increasing, indicating that the positive spatial correlation between China’s national agricultural cultural heritage sites is gradually strengthening.③In terms of influencing factors, the spatial pattern of China’s national agricultural cultural heritage is affected by factors such as regional economic development level, policy guarantee, transportation accessibility, cultural environment, per capita economic development level, population status, primary industry economic development level, secondary industry economic development level, tourism resource endowment, temperature, precipitation, terrain, and rivers. Among them, the impact of tourism resources, regional economic development level, and policy guarantees are more significant. The explanatory power of the interaction between any two factors is greater than that of a single factor, and there are differences in the strength of the interaction between each influencing factor.

Fiscal vertical imbalance and income inequality: A threshold effect analysis based on government expenditure

This study aims to investigate the complex relationship between vertical fiscal imbalance, public expenditure structure, and income distribution disparities, with the goal of providing policy insights for achieving shared prosperity. Employing Generalized Method of Moments (GMM) and threshold analysis, the research reveals key findings: (1) an exacerbation of vertical fiscal imbalance significantly widens the urban-rural income gap; (2) public expenditure structure exhibits threshold effects, resulting in non-linear impacts on income disparity; (3) a unique contribution of our study is the identification of varying threshold effects of urban public expenditure on income disparities within rural areas, urban areas, and the gap between them, underscoring the need for targeted fiscal interventions. These findings highlight the critical role of public expenditure in addressing income distribution issues and offer valuable guidance for upcoming fiscal and tax reforms.

Long-acting reversible and permanent contraceptives utilization and its associated factors among married women who desire no more children in Ethiopia: A multilevel analysis

Objective This study aimed to investigate long-acting reversible and permanent contraceptives (LARPCs) utilization and its associated factors among married women who desire no more children in Ethiopia. Methods Secondary datasets from the 2016 Ethiopian Demographic and Health Survey was used for the study. A total weighted sample of 3,756 married or in union reproductive age women who desire no more children were included in the analysis. Data was cleaned, weighted, and analyzed using STATA Version 14 software. A multi-level logistic regression analysis was conducted to consider the hierarchal nature of the demographic and health survey data. In a multivariable multilevel logistic regression model, an adjusted odds ratio (AOR) with a corresponding 95% confidence interval (CI) and p value <0.05 was used to declare the significant associated factors of LARPCs utilization. Results The overall utilization of LARPCs among married women who desire no more children was 12% [95%CI: 10.99, 13.07]. In the multivariable multilevel analysis; being female household heads [AOR = 0.60; 95%CI: 0.40, 0.92], husband primary level of education [AOR = 1.57; 95%CI: 1.18, 2.07], employed women [AO R = 1.34; 95%CI: 1.04, 1.74], women from middle wealth index [AOR = 1.45; 95%CI: 1.02, 2.07], women who visited health facility in the last 12 months [AOR = 0.69; 95%CI: 0.54, 0.88], women residing in small peripherals [AOR = 0.20, 95%CI: 0.05, 0.82], and women from communities with low poverty [AOR = 2.25, 95%CI: 1.26, 3.99] were significantly associated with LARPCs utilization. Conclusion In Ethiopia, LARPCs utilization among married women who desire no more children was very low. Both individual and community-level factors were significantly associated with LARPCs utilization. Thus, individual and community-level interventions that encourage husband education, maternal occupation, and giving special attention for women who live in small peripheral areas and female-headed households are better.

Comparative metabolic study of planktonic and sessile cells in Salmonella Enteritidis ATCC 13076: Elucidating metabolic pathways driving biofilm formation

Microorganisms tend to accumulate on surfaces, forming aggregates such as biofilms, which grant them resistance to various environmental stressors and antimicrobial agents. This ability has hindered the effective treatment of diseases caused by pathogenic microorganisms, including Salmonella, which is responsible for a significant number of deaths worldwide. This study aimed to compare the metabolic profiles of planktonic and sessile cells of Salmonella Enteritidis using a metabolomics approach. The metabolites extracted from the bacterial cells were analyzed by LC/MS approach. Raw data were analyzed using Thermo Xcalibur v 3.1 software. For data processing, XCMS was used for feature detection, retention time, correction and alignment. The data matrix was analyzed by uni- and multivariate statistical methods (PCA, PLS-DA, Heatmap) in MetaboAnalyst software v 6.0. A total of 121 metabolites were presumptively identified as differential metabolic characteristics between the two bacterial states, and they were associated with their corresponding metabolic pathways. Among the metabolites that exhibited positive modulation in planktonic cells were proline, phenylalanine, which act as precursors of essential metabolites and part of the stress adaptation mechanisms. In addition, putrescine and cadaverine, play crucial roles in growth, stress response, and cell stability In contrast, the most representative metabolites in sessile cells included lysine, adenosine, purines, pyrimidines, and citrate, mainly associated with maintaining cellular homeostasis, stress response and metabolic regulation. Finally, pathway enrichment analysis identified metabolic changes in 11 pathways, predominantly involving purine and pyrimidine metabolism, arginine and proline metabolism, and vitamin B6 metabolism. These findings facilitated the identification of potential metabolic pathways associated with biofilm formation in the sessile cells of Salmonella Enteritidis.

Acceptability, feasibility and appropriateness of intensified health education, SMS/phone tracing and transport reimbursement for uptake of voluntary medical male circumcision in a sexually transmitted infections clinic in Malawi: A mixed methods study

Introduction Uptake of voluntary medical male circumcision (VMMC) remains a challenge in many settings. Innovative implementation strategies are required to scale-up VMMC uptake. Methodology RITe was a multi-faceted intervention comprising transport reimbursement (R), intensified health education (IHE) and SMS/Telephone tracing (Te), which increased the uptake of VMMC among uncircumcised men with sexually transmitted infections (STIs) in Malawi. Using a concurrent exploratory mixed-method approach, we assessed the intervention’s acceptability, feasibility and appropriateness among men with STIs and healthcare workers (HCWs) at Bwaila District Hospital. Participants completed Likert scale surveys and participated in-depth interviews (IDIs) and focus group discussions (FGDs). We calculated percentages of responses to survey items and summarized common themes using thematic analysis. Median scores and interquartile ranges (IQR) were calculated for acceptability, feasibility and appropriateness of each strategy at baseline and end-line and compared using the Wilcoxon signed rank test. Results A total of 300 surveys, 17 IDIs and 4 FGDs were conducted with men and HCWs between baseline and end-line. The mean age for men in the survey was 29 years (SD ±8) and most were married/cohabiting (59.3%). Mean age for HCWs was 38.5 years (SD ±7), and most were female (59.1%). For acceptability, participants agreed that RITe was welcome, approvable, and likable. Despite participants agreeing that RITe was a good idea, fit and suitability influenced appropriateness, particularly at baseline, which improved at end-line for Te and R. For feasibility, HCWs agreed that RITe was easy to implement, but expressed concerns that R (end-line median = 4, IQR: 2, 4) and Te (end-line median = 4, IQR: 4, 4), were unsustainable. Interviews corroborated the survey results. Participants reported that IHE provided important information, Te was a good reminder and R was attractive, but they reported barriers to R and Te such as electricity, limited access to phones and distrust in the government. Conclusions The RITe intervention was acceptable, feasible and appropriate. However, culture/religion and structural barriers affected perceptions of appropriateness and feasibility, respectively. Continued awareness raising on VMMC and addressing setting-specific structural factors are required to overcome barriers that impede demand-creation interventions for VMMC.

Parametric modeling of under-5 children survival among 30 African countries: Lognormal accelerated failure time gamma shared frailty model

Background Under-five mortality continues to be a serious public health concern in low-and middle-income countries, particularly in Africa. This study investigates the probability of under-five survival and its predictors of mortality in the African continent using a recent demographic health survey from 2014–2022. Methods This study utilized recent Demographic and Health Survey data from 30 African countries, encompassing 226,862 live births. This study employed a multivariable lognormal accelerated failure time gamma shared frailty parametric survival regression analysis to identify the predictors of time-to-death among under-five children in these African nations. Result The overall under-five child mortality rate in Africa was 37.55 per 1,000 live births (95% CI: 37.35, 37.74. In this study, children born in Western Africa; children born in Eastern Africa; children born to mothers aged 15–19 years; maternal educational status; maternal decision autonomy; being female; place of delivery; number of ANC visits; children born among mothers who delivered by Cesarean section; mothers who have multiple birth outcome; children who were second birth order; and third birth order and third birth order; children who were small in size at birth; children who were born from a community with a low women education; having poor wealth index; respondents working; mothers delivered at the age between 20–35 were significant predictors of survival time to event of under-five children in Africa. Conclusion This study found that the overall under-five mortality rates remain high across Africa. In this study country region, maternal age, maternal education status, maternal age at first birth, respondent’s employment status, birth outcome, wealth index, birth order, place of delivery, mode of delivery, women’s autonomy in healthcare decision-making, number of antenatal care visits, child’s size at birth, sex of the neonate, and community-level women’s education were found to be significant predictors of survival time to death of under-five children. Addressing these multilevel factors is crucial for developing targeted interventions to reduce under-five mortality further and improve child survival in African countries.

Mathematical and statistical approaches in epidemiological investigation of hospital infection: A case study of the 2015 Middle East Respiratory Syndrome outbreak in Korea

Mathematical and statistical methods are invaluable in epidemiological investigations, enhancing our understanding of disease transmission dynamics and informing effective control measures. In this study, we presented a method to estimate transmissibility using patient-level data, with application to the 2015 MERS outbreak at Pyeongtaek St. Mary’s Hospital, the Republic of Korea. We developed a stochastic model based on individual case data to derive a likelihood function for disease transmission. Through scenario-based analysis, we explored transmission dynamics, including the role of superspreaders, and investigated how mask-wearing impacted infection control within the hospital. Our findings indicated that the superspreader during the MERS outbreak had approximately 25 times higher transmissibility compared to other patients. Under scenarios of prolonged hospital transmission periods, the number of cases could potentially increase threefold. The impact of mask-wearing in the hospital was significant, with reductions in the epidemic scale ranging from 17% to 77%, depending on the type of mask and intervention intensity. This study quantifies key risk factors in hospital-based transmission, demonstrating the effectiveness of intervention measures. The methodology developed here can be readily adapted to other infectious diseases, providing valuable insights for future outbreak preparedness and response strategies.

Correction: An enigma of Malaysia’s low-income young adults: Mediation of financial behaviour on financial well-being and locus of control cohesion

Star ecologist accused of misconduct loses university post

Correction: Correction: A neural network model for online one-shot storage of pattern sequences

Bluesky’s science takeover: 70% of Nature poll respondents use platform

Empowering drones in vehicular network through fog computing and blockchain technology

The performance of drones, especially for time-sensitive tasks, is critical in various applications. Fog nodes strategically placed near IoT devices serve as computational resources for drones, ensuring quick service responses for deadline-driven tasks. However, the limited battery capacity of drones poses a challenge, necessitating energy-efficient Internet of Drones (IoD) systems. Despite the increasing demand for drone flying automation, there is a significant absence of a comprehensive drone network service architecture tailored for secure and efficient operations of drones. This research paper addresses this gap by proposing a safe, reliable, and real-time drone network service architecture, emphasizing collaboration with fog computing. The contribution includes a systematic architecture design and integration of blockchain technology for secure data storage. Fog computing was introduced for the Drone with Blockchain Technology (FCDBT) model, where drones collaborate to process IoT data efficiently. The proposed algorithm dynamically plans drone trajectories and optimizes computation offloading. Results from simulations demonstrate the effectiveness of the proposed architecture, showcasing reduced average response latency and improved throughput, particularly when accessing resources from fog nodes. Furthermore, the model evaluates blockchain consensus algorithms (PoW, PoS, DAG) and recommends DAG for superior performance in handling IoT data. Fog; Drones; Blockchain; PSO; IoT; Vehicular.

‘Do I need to lead this lifestyle to succeed?’ The mental health crises that forced faculty members to change tack

Mathematical and computational modeling for organic and insect frass fertilizer production: A systematic review

Organic fertilizers have been identified as a sustainable agricultural practice that can enhance productivity and reduce environmental impact. Recently, the European Union defined and accepted insect frass as an innovative and emerging organic fertilizer. In the wider domain of organic fertilizers, mathematical and computational models have been developed to optimize their production and application conditions. However, with the advancement in policies and regulations, modelling has shifted towards efficiencies in the deployment of these technologies. Therefore, this paper reviews and critically analyzes the recent developments in the mathematical and computation modeling that have promoted various organic fertilizer products including insect frass. We reviewed a total of 35 studies and discussed the methodologies, benefits, and challenges associated with the use of these models. The results show that mathematical and computational modeling can improve the efficiency and effectiveness of organic fertilizer production, leading to improved agricultural productivity and reduced environmental impact. Mathematical models such as simulation, regression, dynamics, and kinetics have been applied while computational data driven machine learning models such as random forest, support vector machines, gradient boosting, and artificial neural networks have also been applied as well. These models have been used in quantifying nutrients concentration/release, effects of nutrients in agro-production, and fertilizer treatment. This paper also discusses prospects for the use of these models, including the development of more comprehensive and accurate models and integration with emerging technologies such as Internet of Things.

Daily briefing: What went wrong at 23andMe

Dual RNA-seq reveals transcriptome changes during Fusarium virguliforme-Trichoderma afroharzianum interactions

Trichoderma spp. are among the most studied biocontrol agents. While extensive work has been done to understand Trichoderma antagonistic mechanisms, additional research is needed to fully understand how Trichoderma spp. recognize the pathogen-host and the intra-species variability i frequently observed upon interaction with a specific pathogen-host. This study focuses on elucidating the mechanisms underlying observed phenotypic differences among the T. afroharzianum isolates Th19A and Th4 during confrontation with Fusarium virguliforme by investigating differences in their transcriptome at different stages of interaction. In a dual plate assay, Th19A overgrows F. virguliforme, whereas Th4 forms an inhibition zone. Significant differences were observed in the F. virguliforme transcriptome upon interaction with Th19A compared to Th4 and across the different stages of interaction. GO molecular function categories enriched for F. virguliforme genes differed, indicating possible transcriptional plasticity upon interaction with Th19A versus Th4. Significant transcriptome changes were also observed in T. afroharzianum, with several differences in GO-enriched categories between isolates. Several differentially expressed genes-encoding secreted proteins, including CAZymes and CBM1-domain-containing proteins, were up-regulated in Th19A and Th4 upon interaction with the pathogen, even before physical contact, demonstrating possible volatile-mediated recognition of both isolates by F. virguliforme. This study contributes to a better understanding of the interaction between T. afroharzianum and F. virguliforme, which is crucial for developing efficient biological control programs.

Radar versus optical: The impact of cloud cover when mapping seasonal surface water for health applications in monsoon-affected India

Surface water plays a vital role in the spread of infectious diseases. Information on the spatial and temporal dynamics of surface water availability is thus critical to understanding, monitoring and forecasting disease outbreaks. Before the launch of Sentinel-1 Synthetic Aperture Radar (SAR) missions, surface water availability has been captured at various spatial scales through approaches based on optical remote sensing data. A critical drawback of the latter is data loss due to cloud cover, however few studies have quantified this. This study evaluated data loss due to clouds in three Western Ghats (India) districts. These forest-agricultural mosaic landscapes, where water-related diseases are prevalent, experience the Indian monsoon. We compared surface water areas mapped by thresholding 10m Sentinel-1A SAR data with the optical 30m Landsat-derived Joint Research Centre (JRC) Global Surface Water product, currently the only globally available long-term monthly surface water data product. Backscatter thresholds were identified manually, and our Bayesian algorithm found these thresholds were very likely (>97%). While the Sentinel-1 SAR-based and JRC’s optical-based approach mapped surface water extent with high overall accuracy (> 98%) when the cloud cover was low, the unmapped surface water area was substantial in the JRC product during the monsoon months. Across the districts, the average cloud cover in the July-August period was 92% or 90% for 2017 and 2018 respectively, resulting in 25% or 23% of the surface water area being unmapped. Also, the more detailed 10m resolution of Sentinel-1A SAR helped detect the many small water features missed by 30m JRC. Thus, for predicting water-related disease risks linked to small water features or monsoon rainfall, Sentinel-1A SAR is more effective. Finally, automatic backscatter thresholding for unvegetated surface water mapping can be effective if threshold values are adapted to regional-specific backscatter spatial and temporal variations.

Incidence and predictors of mortality among HIV positive children on anti-retroviral therapy in the selected health facilities of West Wollega Zone, Western Ethiopia: Retrospective cohort study

Introduction The mortality rate among Human immunodeficiency Virus (HIV) who have started antiretroviral therapy (ART) continues to be increased in resource-limited countries, despite a decline in developed nations. Furthermore, research within this age group is limited and has not previously been conducted in the study area. Consequently, this study aimed to determine the incidence of mortality and its predictors among HIV-positive children who have been receiving ART at public health facilities in West Wollega. Objective To assess incidence rate and predictors of mortality among HIV-positive children on ART at selected health facilities of West Wollega, Ethiopia, 2022. Methods A retrospective cohort study design was conducted. A simple random sampling method was employed to select 286 children living with HIV who started ART from 01 January 2012 to 31 October 2021. Data were entered into Epi-Data Version 3.1, and STATA Version 14 was used for statistical analysis. A Kaplan-Meir survival curve and Long Rank test were used to estimate survival probability and assess statistical differences. The Cox regression model was used to determine independent predictors of mortality. Results The total follow-up time was 15, 652 child-months, and the overall incidence of mortality was 1.92 (95%CI: 1.34, 2.74) per 1000 child-months. The median time to death following the initiation of ART was 6 months. This study also showed that children with WHO clinical stage III (AHR = 3.4, 95% CI: 1.2, 7.4), stage IV (AHR = 5.4, 95%CI: 1.5, 19.8), Being anemic (AHR = 4.9, 95%CI: 1.8, 13.4), CD4 cell count below threshold (AHR = 3.7, 95%CI = 1.4, 9.5), delayed developmental milestone (AHR = 4.5, 95%CI: 1.7, 11.7) were at higher risk of mortality. Conclusion The overall mortality rate was lower compared to the previous study findings. Anemia, WHO clinical stage, CD4 cell count, and delayed developmental milestones were independent predictors of mortality. Therefore, the focus should be given to all children on ART during the early periods of ART initiation, advanced HIV disease, presence of anemia, severe immune deficiency, and delayed developmental milestones.

Mathematical assessment of the role of temperature on desert locust population dynamics

This study presents a novel non-autonomous mathematical model to explore the intricate relationship between temperature and desert locust population dynamics, considering the influence of both solitarious and gregarious phases across all life stages. The model incorporates temperature-dependent parameters for key biological processes, including egg development, hopper growth, adult maturation, and reproduction. Theoretical analysis reveals the model’s capacity for complex dynamical behaviors, such as multiple stable states and backward bifurcations, suggesting the potential for sudden and unpredictable population shifts. Sensitivity analysis identifies temperature-related parameters as critical drivers of population fluctuations, highlighting the importance of accurate temperature predictions for effective management. Numerical simulations demonstrate the significant impact of temperature on population growth, with optimal conditions promoting rapid development and increased survival, while extreme temperatures can hinder population growth and trigger phase transitions. By providing a deeper understanding of temperature-driven population shifts, this model enhances the ability to predict locust outbreaks, optimize control strategies, and reduce the socio-economic and ecological impacts of locust invasions.