Standard Rate Research Articles

Energetically costly weaponry in the large morph of male stag beetles

AbstractMales of many species develop disproportionately large weapons, and frequently the weapon size increases more quickly with body size in small than in large males—a trend often considered to result from the depletion of developmental resources limiting male weapon exaggeration. Based on the cost‐minimization hypothesis, a shallower weapon‐body size allometric slope in large than in small males could be selected for if the energetic maintenance costs of having oversized weapons increase faster in large than in small males. Whether males of different size groups that differ in the weapon‐body size allometric relationship also differ in the energetic costs of maintaining their weapons has not yet been investigated. Consequently, we studied this using the stag beetle (Cyclommatus mniszechi), in which males are larger in size and have larger mandibles than do females and are divided into two morphs: majors are larger and have longer mandibles than minors. In both male morphs, mandible size increases disproportionately with their body size, but it increases more quickly in minors than in majors. We measured the standard metabolic rate (SMR) of the three types of these beetles (the two male morphs and females) to investigate whether the energetic maintenance cost of carrying weapons differs among them. Body weight explained 80% of the variation in the SMR in the three types of beetles, and SMR increased more quickly with body weight in major males than in minor males or females. Weapon and body size also jointly explained approximately 80% of the variation in the SMR. Whereas SMR increased with body size in all three types of beetles (with a higher rate of increase in major males than in minor males or females), only the major males' SMR increased with weapon size. Overall, being heavier and larger and carrying oversized weapons are energetically costly in major males, something which could constrain the exaggeration of their weapons.

Evaluating the performance of six 1970s off-gas deep retrofit bungalows

This paper presents the energy and environmental performance of whole house energy systems implemented in six 1970s bungalows in South Wales, owned by Swansea Council. The objective was to reduce energy demand and carbon emissions, maximise renewable supply whilst ensuring a comfortable and affordable home for the residents. The whole house energy system for each home involved the installation of a combination of passive and active low carbon solutions. Detailed monitoring was carried out for a year before and for more than 2 years after the work, annual figures have been validated and normalised for weather. Analysis of monitored data confirms that Standard Assessment Performance ratings improved from 12 to 95. The average annual energy consumption across the six bungalows was reduced from 16,117 to 4560 kWh. 2418 kWh was provided by the PV panels and battery, with 1963 kWh of excess electricity that could be sold back to the grid. Real-life average Ground Source Heat Pump CoP was monitored at 3.3. Embodied carbon for retrofitting each house is estimated at 22,980 KgCO2e +/−20%, approximately 5-years carbon payback. Indoor conditions have been improved with internal temperature and relative humidity achieving standards with residents reporting levels of improved comfort satisfaction. Practical Application A whole house energy system demonstrates the benefits of a holistic, fabric and systems retrofit approach. The work informs how gathering data using appropriate methods assists modelling predictions and decisions throughout the retrofit stages. The study demonstrates extensive monitoring as a vital tool to evaluate the performance of the individual components and the whole system within the home, as used by the residents. Performance evaluation is critical in identifying issues, allowing resolutions to be made both immediately on-site as well for longer term, follow on retrofit programmes. Real-life performance evaluation and visualisation methods are transferable across global building industry.

Country and continent-wise trends in mortality rates of ovarian cancer from 1980-2021: An analysis of GBD study 2021.

148 Background: Ovarian cancer is one of the major causes of cancer related deaths in women worldwide. Early detection, primarily via ultrasound , can result in lower mortality and morbidity. We present a comprehensive evaluation derived from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, depicting the ovarian cancer associated mortality pattern from 1980 to 2021. Methods: Data were methodically retrieved from the Global Burden of Diseases (GBD) study, which included age-standardized death rates, Years of Lost Life (YLL), and disability-adjusted life years (DALYs). The dataset was stratified globally and categorized by continent, with Africa divided into Northern, Southern, Eastern, Western, and Central regions, and by World Bank income levels. Joinpoint Regression was employed to determine average annual percentage changes (AAPC). Results: Globally, the Age standardized death rates (ASDR) for ovarian cancer had an overall decline from 1980 to 2021. In 1980, the ASDR was 4.64 (95% UI: 4.3-5.14), and it declined to 4.05 (AAPC: -0.315; 95% CI: -0.35 to -0.27) in 2021. Globally, the disability-adjusted life-years (DALYs) rate was 132.4 (95% UI: 121.3–145.6) per 100,000 people in 1990, and it decreased to 115.14 (AAPC: -0.44; 95% CI: -0.52 to -0.36) in 2021. From 1990 to 2021, the age-standardized years of life lost (YLL) showed a uniform drop with an AAPC of -0.36 (95% CI: -0.40 to -0.31). However, in continent wise analysis, while the Americas and Europe had continuously declining ASDRs, Asia and Africa had an increasing trend throughout the predetermined time frame. From 1980 to 2021, America had an AAPC of -0.67 (95% CI: -0.69 to -0.65). Similarly, Europe also had a decreasing trend from 1980 to 2021 with an AAPC of -0.48 (95% CI: -0.50 to -0.45). The AAPC for Africa was 1.203 (95% CI: 1.19 to 1.21), showing a greater incline compared to the other continents. The AAPC for Asia was 0.54 (95% CI: 0.527 to 0.563). During further analysis of the African region, we observed that southern and eastern Africa had the highest ASDRs. According to World Bank income levels, low-income and lower-middle-income countries had increasing death rates, while high and upper-middle income countries had decreasing death rates from 1980 to 2021. Conclusions: The study disclosed a global decline in ovarian cancer fatality rates from 1980 to 2021. Although significant progress has been made in the Americas and Europe, mortality rates have risen in Asia and Africa, with southern and eastern Africa exhibiting particularly high rates. An increase in death rates is also observed in low- and lower-middle-income countries, contrasting with an overall decrease globally and in high-income nations.

Redshift Prediction with Images for Cosmology Using a Bayesian Convolutional Neural Network with Conformal Predictions

In the emerging era of big data astrophysics, large-scale extragalactic surveys will soon provide high-quality imaging for billions of celestial objects to answer major questions in astrophysics such as the nature of dark matter and dark energy. Precision cosmology with surveys requires accurate photometric redshift (photo-z) estimation with well-constrained uncertainties as inputs for weak lensing models to measure cosmological parameters. Machine learning methods have shown promise in optimizing the information gained from galaxy images in photo-z estimation; however, many of these methods are limited in their ability to estimate accurate uncertainties. In this work, we present one of the first applications of Bayesian convolutional neural networks (BCNNs) for photo-z estimation and uncertainties. In addition, we use conformal mapping to calibrate the photo-z uncertainties to achieve good statistical coverage. We use the public GalaxiesML data set of ∼300k galaxies from the Hyper Suprime-Cam survey containing five-band photometric images and known spectroscopic redshifts from 0 < z < 4. We find that the performance is much improved when using images compared to photometry, with the BCNN achieving 0.098 rms error, a standard outlier rate of 3.9%, a 3σ outlier rate of 4.5%, and a bias of 0.0007. The performance drops significantly beyond z > 1.5 due to the relative lack of training data beyond those redshifts. This investigation demonstrates the power of using images directly and we advocate that future photo-z analysis of large-scale surveys include galaxy images.

Impact of an Epstein-Barr Virus Serology-Based Screening Program on Nasopharyngeal Carcinoma Mortality: A Cluster-Randomized Controlled Trial.

Screening for nasopharyngeal carcinoma (NPC) has shown an improvement in early detection and survival rates of NPC in endemic regions. It is critical to evaluate whether NPC screening can reduce NPC-specific mortality in the population. Sixteen towns in Sihui and Zhongshan cities, China, were selected; eight were randomly allocated to the screening group and eight to the control group. Residents age 30-69 years with no history of NPC were included from January 1, 2008, to December 31, 2015. Residents in the screening towns were invited to undergo serum Epstein-Barr virus (EBV) viral capsid antigen/nuclear antigen 1-immunoglobulin A antibody tests; others received no intervention. The population was followed until December 31, 2019. Nonparametric tests and Poisson regression models were used to estimate the screening effect on NPC mortality, accounting for the cluster-randomized design. The trial is registered with ClinicalTrials.gov (identifier: NCT00941538). A total of 174,943 residents in the screening group and 186,263 residents in the control group were included. NPC incidence and overall mortality were similar between the two groups. A total of 52,498 (30.0% of 174,943) residents participated in the serum EBV antibody test. The overall compliance rate for endoscopic examination and/or biopsies among baseline and ever-classified high-risk participants was 65.9% (1,110 of 1,685) and 67.6% (1,703 of 2,518), respectively. A significant 30% reduction in NPC mortality was observed in the screening group compared with the control group (standardized NPC-specific mortality rate of 8.2 NPC deaths per 1,000 person-years versus 12.5; adjusted rate ratio [RR], 0.70 [95% CI, 0.49 to 0.997]; P = .048). This benefit was most evident among individuals age 50 years and older (RR, 0.56 [95% CI, 0.37 to 0.85]; P = .007) compared with those younger than 50 years (RR, 0.96 [95% CI, 0.64 to 1.46]; P = .856). In this 12-year trial, EBV antibody testing resulted in a significant reduction in NPC mortality.

Convolution Analysis in Electrodeposition

Convolution is a well established method for data analysis for electrochemical processes where both product and reactants are soluble. Advantages of convolution analysis include (a) facile evaluation of kinetic and system parameters, (b) ready corrections for nonfaradaic uncompensated resistance and double layer charging, (c) track of surface concentrations with time, independent of the voltage perturbation sequence, and (d) ease of convolution calculation from digitized current data. Here, equations are derived for convolution of electrodeposition data and a data analysis protocol is presented. Advantages are found for convolution analysis in electrodeposition. Parameters that can be determined from convolution analysis in electrodeposition are standard heterogeneous rate constant k 0 and exchange current density j 0, transfer coefficients α and β, formal potential E0′ , resistance to charge transfer, and diffusion coefficient of the solution soluble reactant D M . Convolution in electrodeposition is illustrated for silver deposited from an ionic liquid onto a glassy carbon electrode, where experimental data are tracked cyclic voltammetrically.

Targeted monetary policy, dual rates, and bank risk-taking

We assess whether dual interest rates – central bank funding at rates below the interest rates on reserves – influence the size and composition of bank credit. We measure exposure to the policy using daily reactions of bank funding costs to the announcement of the recalibration of the ECB’s TLTROs in April 2020. We then use the Euro area credit register to follow the evolution of bank lending conditions and risk-taking. We find that the measure had a strong positive effect on bank credit and, in contrast to a standard rate cut, was not accompanied by an increase in risk-taking.

International comparison of hospitalizations and emergency department visits related to mental health conditions across high-income countries before and during the COVID-19 pandemic.

To explore variation in rates of acute care utilization for mental health conditions, including hospitalizations and emergency department (ED) visits, across high-income countries before and during the COVID-19 pandemic. Administrative patient-level data between 2017 and 2020 of eight high-income countries: Canada, England, Finland, France, New Zealand, Spain, Switzerland, and the United States (US). Multi-country retrospective observational study using a federated data approach that evaluated age-sex standardized rates of hospitalizations and ED visits for mental health conditions. There was significant variation in rates of acute mental health care utilization across countries. Among the subset of four countries with both hospitalization and ED data, the US had the highest pre-COVID-19 combined average annual acute care rate of 1613 episodes/100,000 people (95% CI: 1428, 1797). Finland had the lowest rate of 776 (686, 866). When examining hospitalization rates only, France had the highest rate of inpatient hospitalizations of 988/100,000 (95% CI 858, 1118) while Spain had the lowest at 87/100,000 (95% CI 76, 99). For ED rates for mental health conditions, the US had the highest rate of 958/100,000 (95% CI 861, 1055) while France had the lowest rate with 241/100,000 (95% CI 216, 265). Notable shifts coinciding with the onset of the COVID-19 pandemic were observed including a substitution of care setting in the US from ED to inpatient care, and overall declines in acute care utilization in Canada and France. The study underscores the importance of understanding and addressing variation in acute care utilization for mental health conditions, including the differential effect of COVID-19, across different health care systems. Further research is needed to elucidate the extent to which factors such as workforce capacity, access barriers, financial incentives, COVID-19 preparedness, and community-based care may contribute to these variations. Approximately one billion people globally live with a mental health condition, with significant consequences for individuals and societies. Rates of mental health diagnoses vary across high-income countries, with substantial differences in access to effective care. The COVID-19 pandemic has exacerbated mental health challenges globally, with varying impacts across countries. This study provides a comprehensive international comparison of hospitalization and emergency department visit rates for mental health conditions across eight high-income countries. It highlights significant variations in acute care utilization patterns, particularly in countries that are more likely to care for people with mental health conditions in emergency departments rather than inpatient facilities The study identifies temporal and cross-country differences in acute care management of mental health conditions coinciding with the onset of the COVID-19 pandemic.

The predictive value of chest X-ray for the depth of tracheal intubation in infants

ObjectiveTo determine the predictive value of chest X-ray for the depth of tracheal intubation in infants. MethodsBasic data of 161 infants under 3 years old was collected. Tracheal length was measured on preoperative chest radiographs to guide intubation depth. Correlation analysis was performed to examine relationships between tracheal length, age, and body weight. Results161 cases (male/female=142/19, no significant difference in sex, p=0.09) were included, aged from 1 month to 28 months, weight from 2.5kg to 18.0kg. The endotracheal intubation depth reached the standard rate was 100%, with 0 cases of over-deep or over-shallow intubation. Correlation analysis showed that tracheal length was positively correlated with both age and body weight, with stronger correlations observed in infants aged 1-12 months (r=0.751 for age, r=0.672 for weight, p<0.01) compared to those aged 13-28 months (r=0.672 for age, r=0.408 for weight, p<0.01). ConclusionDirect measurement of tracheal length on routinely performed chest X-rays is simple, feasible and safe, and may be another choice for guiding the depth of tracheal intubation in children.

Features of the epidemiology of esophageal cancer among the population of Ukraine for the period from 2016 to 2023

Esophageal cancer is an extremely serious and highly relevant issue with substantial medical and social significance. The significance is primarily due to its aggressive nature, as esophageal cancer progresses rapidly and is often diagnosed in its late stages. Late detection limits treatment options and generally leads to poorer survival outcomes, making it one of the most challenging cancers to manage. A study of data from the National Cancer Registry of Ukraine examined trends in standardized morbidity and mortality rates from 2016 to 2021. Over this period, the standardized morbidity rate decreased by 16.3%, while the standardized mortality rate dropped by 15.6%, suggesting some improvements in early detection and treatment approaches during those years. However, the outbreak of hostilities in Ukraine in 2022 created substantial barriers to healthcare operations, particularly in cancer centers. According to official data, military actions disrupted data collection, making it impossible to calculate standardized morbidity and mortality rates per capita for years 2022–2023. By the end of 2023, only data on the total number of patients registered in cancer care institutions were available. This lack of comprehensive data limits understanding of current trends in esophageal cancer and complicates planning for healthcare resources in the coming years. Wartime conditions pose unique challenges, as access to quality medical care may be restricted or delayed. For conditions like esophageal cancer, where early detection is crucial, limited access can lead to a higher likelihood of advanced-stage diagnoses, ultimately impacting prognosis and survival rates. These circumstances underscore the importance of maintaining continuity in cancer care, even under adverse conditions, through targeted healthcare planning. Keywords: analysis of dynamics, cancer, mortality and morbidity.

Insights on Poverty-based Inequality in Old-age Mortality in India

BackgroundAs the global population ages, understanding the effect of poverty on old-age mortality becomes increasingly important, especially in India, which is undergoing significant demographic and socio-economic changes. Although previous research has established a link between poverty and mortality, there is a critical need for panel studies to investigate this relationship specifically among older adults. This study addresses this gap by using panel data to examine the association between initial poverty status and subsequent mortality among older adults in India. Additionally, it explores the factors contributing to mortality disparities between poor and non-poor older adults.MethodsWe analyzed panel data from two rounds of the India Human Development Survey. The age-sex standardized old-age mortality rates for poor and non-poor older adults were calculated using direct standardization. Mortality disparities were evaluated through bivariate and proportion tests, as well as multivariable logistic regression analyses. The Fairlie decomposition technique was employed to identify factors contributing to these disparities, with sensitivity analyses performed to ensure the robustness of the findings.ResultsThe age-sex standardized old-age mortality rate for the poor was 31.9 per 100 people, with a 1.15 times higher likelihood of mortality [95% CI: (1.04,1.27)] between round-I to round-II compared to non-poor counterparts. Factors such as household wealth (33.6%), social class (17.1%), education (12%), and occupation (4.3%) were significant indicators of the poverty gap in old-age mortality. Surprisingly, chronic diseases, age, and gender negatively affect mortality disparity, while higher mortality in extended families suggests a weakening traditional support system.ConclusionThe findings underscore the importance of addressing ageist attitudes and enhancing social safety nets and affordable healthcare for older adults, who face higher risks of poverty and premature death. The elevated mortality among those in prolonged poverty cycles highlights the need for policymakers to reconsider universal support policies for older individuals. Specifically, if non-poor older adults have longer lifespans, policies centred solely on poor may not effectively address the needs of all older individuals.

Redox Reaction of Some Nitroxyl Radicals in 1-Butyl-1-Methylpyrrolidinium Bis(fluorosulfonyl)amide in the Presence and Absence of Lithium Ion

The electrochemical behavior of 2,2,6,6,-tetramethylpiperidine-1-oxyl (TEMPO) and 4-oxo-TEMPO was investigated in 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)amide (BMPFSA) in the absence and presence of LiFSA. The redox reactions of TEMPO+/TEMPO and 4-oxo-TEMPO+/4-oxo-TEMPO were observed on a platinum electrode in the absence and presence of 0.5 M LiFSA. The formal potentials of TEMPO+/TEMPO and 4-oxo-TEMPO+/4-oxo-TEMPO were positively shifted in the presence of LiFSA, indicating that the interaction of TEMPO and 4-oxo-TEMPO with Li+ altered the energies of the singly occupied molecular orbitals of TEMPO and 4-oxo-TEMPO. The diffusion coefficients and standard rate constants were evaluated by chronoamperometry and electrochemical impedance spectroscopy, respectively. The diffusion coefficient and the standard rate constant were suggested to be controlled not only by the viscosity but also by the interaction between the nitroxyl radicals and Li+.

S@FeS2 Core-Shell Cathode Nanomaterial for Preventing Polysulfides Shuttling and Forming Solid Electrolyte Interphase in High-Rate Li-S Batteries.

Lithium-sulfur (Li-S) battery is a potential next-generation energy storage technology over lithium-ion batteries for high capacity, cost-effective, and environmentally friendly solutions. However, several issues including polysulfides shuttle, low conductivity and limited rate-capability have hampered its practical application. Herein, a new class of cathode active material with perfect core-shell structure is reported, in which sulfur is fully encapsulated by conductivity-enhancing FeS2 (named as S@FeS2), for high-rate application. Surface-stabilized S@FeS2 cathode exhibits a stable cycling performance under 2 - 20 times higher rates (1-2 C, charged in 30-60min) than standard rates (e.g., 0.1-0.5C, charged in 2-10h), without polysulfides shuttle event. Surface analysis results reveal the unprecedented formation of a stable solid electrolyte interphase (SEI) layer on S@FeS2 cathode, which is distinguished from other sulfur-based cathodes that are not able to form the SEI layer. The data suggest that the prevention of polysulfides shuttling is owing to the surface protection effect of FeS2 shell and the SEI layer formation overlying core-shell S@FeS2. This unique and potential material concept proposed in the present study will give insight into designing a prospective fast charging Li-S battery.

Shifts in motivation to quit cigarette smoking associated with IQOS use

IntroductionIQOS, a heated tobacco product (HTP), is among a growing number of noncombustible nicotine delivery alternatives marketed to people who smoke combustible cigarettes and are interested in less harmful alternatives. Little is known regarding whether IQOS use and IQOS-associated effects impact motivation to quit cigarette smoking. MethodsNon-treatment-seeking adult daily smokers (n = 87) completed a within-subjects study consisting of a baseline ad-lib smoking period (days 1–5), two laboratory visits (days 6–7) involving IQOS exposure, and a two-week period where participants were instructed to switch from smoking cigarettes to using IQOS (days 8–21). Motivation to quit smoking was measured on days 1 and 22. ResultsA generalized linear model revealed a significant increase in motivation to quit smoking across the 14-day switch phase with an increase of 1.47 ladder steps (Δ=1.47, sd = 1.98, t(86) = 6.92, p < 0.0001), increasing from 5.30 to 6.80. Candidate predictors were identified through a stepwise selection procedure, which resulted in a final model with two predictors, the standardized HeatStick substitution rate (b = 0.54, (CI95% 0.13–0.95), p = 0.01) and standardized relative risk perception score (b = 0.45, (CI95% 0.04–0.85) p = 0.03), ConclusionsAmong those uninterested in quitting cigarette smoking within the next month, IQOS use was associated with increased motivation to quit. Motivation to quit smoking may not be a necessary prerequisite for promoting smoking behavior change but rather bolstered by smoking behavior change in the context of HTP use. Greater perceptions of risk reduction may ultimately aid the transition from combustible to noncombustible tobacco products.

Metabolic rate and mitochondrial physiology adjustments in Arctic char (Salvelinus alpinus) during cyclic hypoxia.

Diel fluctuations of oxygen levels characterize cyclic hypoxia and poses a significant challenge to wild fish populations. Although recent research has been conducted on the effects of hypoxia and reoxygenation, mechanisms by which fish acclimatize to cyclic hypoxia remain unclear, especially in hypoxia-sensitive species. We hypothesized that acclimation to cyclic hypoxia requires a downregulation of their aerobic metabolic rate (MR) and an upregulation of mitochondrial respiratory capacities to mitigate constraints on aerobic metabolism and the elevated risk of oxidative stress upon reoxygenation. We exposed Arctic char (Salvelinus alpinus) to ten days of cyclic hypoxia and measured their MR and mitochondrial physiology to determine how they cope with fluctuating oxygen concentrations. We measured oxygen consumption as a proxy of MR and observed that Arctic char defend their standard metabolic rate but decrease their routine metabolic rate during hypoxic phases, presumably through the repression of spontaneous swimming activities. At the mitochondrial level, acute cyclic hypoxia increases oxygen consumption without ADP (CI-LEAK) in liver and heart. Respiration in the presence of ADP (OXPHOS) temporarily increases in the liver and decreases in the heart. Cytochrome c oxidase (COX) affinity with oxygen also increases at day 3 in the liver. However, no change occurs in the brain, which is likely primarily preserved through preferential perfusion (albeit not measured in this study). Finally, in vivo measurements of reactive oxygen species revealed the absence of an oxidative burst in mitochondria in the cyclic hypoxia group. Our study shows that Arctic char acclimatize to cyclic hypoxia through organ-specific mitochondrial adjustments.

Proportional increment of oxygen consumption, heart rate and core body temperature in the digesting Python bivittatus.

The Burmese python has a remarkable digestive physiology with large elevations of metabolic rate and heart rate following feeding. Here, we investigated the relationship between heart rate, oxygen consumption and core body temperature during digestion in five pythons (Python bivittatus) by implantation of data loggers. The snakes were placed in respirometers at 30±0.1°C for 26 days and voluntarily ingested three meals of different size, whilst heart rate, core body temperature and oxygen consumption rate were measured continuously. Both oxygen consumption and heart rate increased severalfold during digestion, and metabolic heat production increased core body temperature by 2°C, explaining 12% of the observed tachycardia. The rise in core body temperature means that standard metabolic rate increased during digestion, and we estimate that failure to account for core body temperature leads to a 4% overestimation of the specific dynamic action (SDA) response. Our study reveals a close correlation between oxygen consumption and heart rate during digestion, further supporting the use of heart rate as a proxy for metabolism.

The Dynamic Behavior of a Stochastic SEIRM Model of COVID-19 with Standard Incidence Rate

This paper studies the dynamic behavior of a stochastic SEIRM model of COVID-19 with a standard incidence rate. The existence of global solutions for dynamic system models is proven by integrating stochastic process theory and the concept of stopping times, together with the contradiction method. Moreover, we construct appropriate Lyapunov functions to analyze system stability and apply Dynkin’s formula and Fatou’s lemma to handle stopping times and expectations of stochastic processes. Notably, the extinction study provides mathematical proof that under the given system dynamics, the total population does not grow indefinitely but tends to stabilize over time. The properties of the diffusion matrix are harnessed to guarantee the system’s stationary distribution. Conclusively, numerical simulations confirm the model’s extinction outcomes.

Association between automatic milking system parameters and intramammary infections in dairy cows at dry-off

IntroductionThe current global concern over increasing antimicrobial resistance among animal and human pathogens has motivated efforts to reduce antimicrobial drug use in food animals and its impact on antimicrobial resistance. One such strategy is to use selective dry cow therapy (SDCT) in dairy cows, which involves treating only cows with intramammary infection (IMI) at dry-off. However, efficient methods are needed to identify cows with IMI at dry-off to implement SDCT. Automatic Milking Systems (AMS) data may help farmers identify cows with IMI when individual Somatic Cell Count (SCC) is not routinely tested. This study assessed the correlation between cow-level and quarter-level AMS parameters and IMI at dry-off.Methods &amp;amp; ResultsA total of 733 udder quarters (comprising both Primiparous [PRIM] and Multiparous [MULT] cows) were sampled and categorized for IMI based on bacterial growth and SCC. Data were aggregated both daily and into 7-day and 15-day intervals preceding dry-off. The quarter-level prevalence of bacterial growth at dry-off was 24.28% overall. When stratified by parity, logistic regression analysis at 15 days to dry-off revealed that the average difference in mastitis detection index (MDi) in PRIM, MDi, and standard deviation milk flow rate in MULT were associated with increased odds of IMI at dry-off. Similarly, data from 7 days to dry-off revealed that average peak milk flow rate in PRIM, and MDi in MULT were associated with increased odds of IMI at dry-off. However, an increase in average milk yield was associated with decreased odds of IMI.Discussion &amp;amp; ConclusionOur findings underscore the significance of MDi, milk flow rate, peak milk flow rate, and milk yield in predicting IMI at dry-off. Notably, stronger associations were observed with data collected 7 days preceding dry-off. Further research is warranted to refine and validate algorithms amalgamating these variables for precise IMI prediction in cows at dry-off.

Dynamics and parameter identification of SIRDS models with aging population factor

Some infectious diseases can cause individuals’ death, and aging factor is not negligible in the disease-induced death. In addition, incidence rate often plays a great role in modeling the spread of diseases. Hence, we consider two Susceptible–Infective–Recovered–Deceased–Susceptible (SIRDS) models with aging population factor and different incidence rates in this paper. The first model assumes the bilinear incidence rate, whereas the second model assumes the standard incidence rate. We investigate the dynamic properties of each model through both analytical and numerical approaches. Our results indicate that the dynamical properties of the first model are entirely dominated by the basic reproduction number, while additional condition is needed for the second one. Moreover, for the first model without vital dynamics and re-susceptibility, we derive an equation for the final size, analyze the solution of the implicit equation and identify some critical model parameters. Finally, numerical simulations are conducted to shed some light on the development of control strategies and to verify theoretical results.

Depressive symptoms and suicidal ideation among university students before and after the COVID-19 pandemic

BackgroundThe COVID-19 pandemic and lockdown have had negative effects on students' mental health. However, little information is available regarding the frequencies of depressive symptoms and suicidal ideation during the post-pandemic period. We aimed to determine the effect of the COVID-19 pandemic on depressive symptoms and suicidal ideation among French university students. MethodsIn this comparative study, 4463 students were recruited during the pre-COVID-19 pandemic period (2013-2020) and 1768 students, during the post-COVID-19 pandemic period (2022-2023). Standardized frequencies of depressive symptoms and suicidal ideation were compared between the two time periods. Changes in the level of depressive symptoms and suicidal ideation between the pre- and post-pandemic periods, were then analyzed using interrupted time series analysis. ResultsCompared to participants from the pre-pandemic sample, participants from the post-pandemic sample had higher standardized rates of depressive symptoms (40.6 % vs 25.6 %) and suicidal ideation (29.3 % vs 21.1 %). Segmented logistic regression showed an about 50 % increased risk of depressive symptoms (aOR, 1.47; 95 % CI, 1.01–2.13) and a 100 % increased risk of suicidal ideation (aOR, 2.00; 95 % CI, 1.33–3.00) in the post-pandemic period. Before the pandemic, there was no significant time-trend for depressive symptoms (aOR, 1.002; 95 % CI, 0.999–1.006) and suicidal thoughts (0.999–1.006; aOR, 0.999; 95 % CI, 0.995–1.002). LimitationsPotential biases related to self-selection of participants in the study and information bias. History of depression and suicide attempt were self-reported. ConclusionsThese findings reveal an alarming deterioration of students' mental health in the post-pandemic period compared to the pre-pandemic era.