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Highly deformable flapping membrane wings suppress the leading edge vortex in hover to perform better
Airborne insects generate a leading edge vortex when they flap their wings. This coherent vortex is a low-pressure region that enhances the lift of flapping wings compared to fixed wings. Insect wings are thin membranes strengthened by a system of veins that does not allow large wing deformations. Bat wings are thin compliant skin membranes stretched between their limbs, hand, and body that show larger deformations during flapping wing flight. This study examines the role of the leading edge vortex on highly deformable membrane wings that passively change shape under fluid dynamic loading maintaining a positive camber throughout the hover cycle. Our experiments reveal that unsteady wing deformations suppress the formation of a coherent leading edge vortex as flexibility increases. At lift and energy optimal aeroelastic conditions, there is no more leading edge vortex. Instead, vorticity accumulates in a bound shear layer covering the wing’s upper surface from the leading to the trailing edge. Despite the absence of a leading edge vortex, the optimal deformable membrane wings demonstrate enhanced lift and energy efficiency compared to their rigid counterparts. It is possible that small bats rely on this mechanism for efficient hovering. We relate the force production on the wings with their deformation through scaling analyses. Additionally, we identify the geometric angles at the leading and trailing edges as observable indicators of the flow state and use them to map out the transitions of the flow topology and their aerodynamic performance for a wide range of aeroelastic conditions.
Impact of manufacturers’ eco-design decisions on the closed-loop supply chain under recycling rate regulations
To address increasingly severe environmental issues, various countries have introduced relevant environmental protection regulations. This paper proposes a new government regulation measure to encourage manufacturers to improve recycling rates. Governments set recycling rate targets and reward-penalty mechanisms. This paper constructs a game model involving a manufacturer and a remanufacturer within a closed-loop supply chain system. It studies the equilibrium decisions in three scenarios: no government intervention, manufacturers not taking improvement measures despite government-set recycling rate targets, and manufacturers adopting ecological design after such targets are established. Results indicate that after governments establish recycling rate target: (1) After manufacturers adopt ecological design, the prices of new and remanufactured products decrease, sales volume increases, and the profits of both manufacturers and remanufacturers rise. Therefore, manufacturers would be well-advised to adopt eco-design strategies to enhance the level of recycling. (2) As the recycling rate target increase, the level of ecological design decreases, and the prices of new and remanufactured products rise. It is recommended that governments initially set lower recycling rate targets and then gradually increase them. (3) With the increase in the reward-penalty coefficient, the level of ecological design rises, and the price of new products first increases and then decreases. When remanufacturing is unrestricted, the prices of remanufactured products decrease; however, when remanufacturing is restricted, the prices of remanufactured products first increase and then decrease. Therefore, governments would be well-advised to establish a relatively high reward-penalty coefficient.
Environmental impact and phenotypic stability in potato clones resistant to late blight Phytophthora infestans (Mont) de Bary, resilient to climate change in Peru
Potato is one of the three most important foods in the world’s diet and is staple in the Peruvian highlands. This crop is affected by late blight, a disease that if not controlled in time can decimate production. The oomycete (Phytophthora infestans) causing this disease is controlled using fungicides, which affect the environment and human health, another form of control is the use of resistant cultivars. 30 potato clones from the LBHTC2 population were evaluated, with the objective of selecting clones with high levels of resistance to this disease, stable for tuber yield, low environmental impact and high economic profitability. The clones were planted in three field experiments in the 2021–2022 growing season. Two experiments with and without late blight chemical control in Oxapampa and Huánuco and one experiment under normal conditions of a potato crop in El Mantaro, Junin, using randomized complete blocks with three replications. The cultivars Yungay, Amarilis and Kory were used as controls for late blight resistance and tuber yield. Late blight resistance and environmental impact were determined based on experiments with and without control in Huánuco and Oxapampa. Yield stability and economic profitability were evaluated based on information from the three experiments. Clones CIP316375.102, CIP316361.187, CIP316367.117, CIP316356.149, CIP316367.147 were the ones that presented the highest yields, high Late blight resistance, phenotypically stable for tuber yield, with low environmental impact and high economic profitability, superior to control cultivars. These clones have high potential for sustainable production systems that allow reducing environmental impact, increasing economic profitability and improving producers’ living standards.
The temporal variation in pesticide concentrations within matured French wines
Numerous organizations worldwide are diligently working to regulate the composition of food products, with a particular focus on pesticide content. Each year, several substances are classified as hazardous to human health and subsequently banned from agricultural use. In this study, we address the age-old question: "Does wine improve with time?" from the context of pesticide composition. We gathered wine samples from renowned French winemaking regions, covering the years 1935 to 2000, to assess pesticide levels and identify specific substances. Our objective was to determine if any currently banned pesticides were present in these aged wines and whether the detected levels pose health risks under typical daily consumption patterns. Our findings revealed the presence of trace amounts of 21 different pesticides proceeding from Plant Protection Products (PPPs), in most of the wine samples, albeit at levels considered non-threatening to human health. Notably, one sample exhibited an alarmingly high concentration of carbaryl, surpassing toxic consumption thresholds. This study prompts discussions regarding the prioritization of pesticide testing in various products and whether stringent regulations should be upheld in the wine selling collectors sector.
Macrophage-P2X4 receptors pathway is essential to persistent inflammatory muscle hyperalgesia onset, and is prevented by physical exercise
Peripheral inflammation may lead to severe inflammatory painful conditions. Macrophages are critical for inflammation; modulating related pathways could be an essential therapeutic strategy for chronic pain diseases. Here we hypothesized that 1) Macrophage-P2X4 receptors are involved in the transition from acute to persistent inflammatory muscle hyperalgesia and that 2) P2X4 activation triggers a pro-inflammatory phenotype leading to Interleukin-1β (IL-1β) increase. Once physical exercise prevents exacerbated inflammatory processes related to chronic diseases including chronic muscle pain, we also hypothesized that 3) physical exercise, through PPARγ receptors, prevents P2X4 receptors activation. With pharmacological behaviour, biomolecular analysis and swimming physical exercise in a mouse model of persistent inflammatory muscle hyperalgesia we demonstrated that P2X4 receptors are essential for transitioning from acute to persistent inflammatory muscle hyperalgesia; Phosphorylation of p38MAPK indicated P2X4 signalling activation associated with inflammatory macrophage and an increase of IL-1β expression in skeletal muscle; Exercise-PPARγ receptors prevented phosphorylation of p38MAPK in muscle tissue. Our findings suggest that exercise-PPARγ modulates the acute inflammatory phase of developing persistent muscle hyperalgesia by controlling p38MAPK-related P2X4 signalling. These highlight the great potential of modulating macrophage phenotypes and P2X4 receptors to prevent pain conditions and the ability of physical exercise to prevent inflammatory processes related to chronic muscle pain.
Home-based nurturing care practices for children under five with low socioeconomic position in Santo Domingo, Dominican Republic
Background In the Dominican Republic about 14.5% of children do not reach their full potential by age five, with children of low socioeconomic position most affected. The Nurturing Care Framework is an evidence-informed actionable framework to help children thrive, but we must first understand cultural contexts and childrearing practices that contribute to delay. This study applies the Nurturing Care Framework to explore the context of home-based care among young children in the Dominican Republic. Methods We conducted a sociodemographic survey and semi-structured qualitative interview with 25 mothers ages 19–42 (7 under the age of 18 at first birth) with low socioeconomic position and children under five that live in the capital city Santo Domingo. We asked in-depth questions about the Nurturing Care Framework’s domains of responsive caregiving and opportunities for early learning. We used consensual coding and deductive thematic analysis to analyze transcriptions, examined convergence and divergence in themes between adolescent and adult mothers, and organized themes using concept mapping. Results A few mothers provide responsive caregiving to their child, but they are unaware of its benefit to their child’s development. Adolescent mothers expressed lower confidence in their mothering skills. Across age groups, mothers did not see themselves as agents of change in their child’s early learning process and allow several hours of videos each day. Mothers provide children opportunities for learning through social interaction, a possible strength among this population. With regards to security and safety, about half of mothers use corporal punishment, all but one of these is an adolescent mother. Conclusion Findings highlight the need for parenting programs that build on strengths such as child-to-child social interaction and provide parents with opportunities to develop knowledge and skills to provide early learning opportunities. Interventions should target families with low socioeconomic position and adolescent mothers.
Enhancing PM2.5 prediction by mitigating annual data drift using wrapped loss and neural networks
In many deep learning tasks, it is assumed that the data used in the training process is sampled from the same distribution. However, this may not be accurate for data collected from different contexts or during different periods. For instance, the temperatures in a city can vary from year to year due to various unclear reasons. In this paper, we utilized three distinct statistical techniques to analyze annual data drifting at various stations. These techniques calculate the P values for each station by comparing data from five years (2014-2018) to identify data drifting phenomena. To find out the data drifting scenario those statistical techniques and calculate the P value from those techniques to measure the data drifting in specific locations. From those statistical techniques, the highest drifting stations can be identified from the previous year’s datasets To identify data drifting and highlight areas with significant drift, we utilized meteorological air quality and weather data in this study. We proposed two models that consider the characteristics of data drifting for PM2.5 prediction and compared them with various deep learning models, such as Long Short-Term Memory (LSTM) and its variants, for predictions from the next hour to the 64th hour. Our proposed models significantly outperform traditional neural networks. Additionally, we introduced a wrapped loss function incorporated into a model, resulting in more accurate results compared to those using the original loss function alone and prediction has been evaluated by RMSE, MAE and MAPE metrics. The proposed Front-loaded connection model(FLC) and Back-loaded connection model (BLC) solve the data drifting issue and the wrap loss function also help alleviate the data drifting problem with model training and works for the neural network models to achieve more accurate results. Eventually, the experimental results have shown that the proposed model performance enhanced from 24.1% -16%, 12%-8.3% respectively at 1h-24h, 32h-64h with compared to baselines BILSTM model, by 24.6% -11.8%, 10%-10.2% respectively at 1h-24h, 32h-64h compared to CNN model in hourly PM2.5 predictions.
Analogical reasoning in first and second languages
This study investigated how linguistic predictors such as word frequencies, the difficulty and creativity of problems, and the category of problems contribute to analogical reasoning in L1 and L2. This study also investigated how different types of similarities (i.e., perceptual and relational similarities) are processed in analogical reasoning. In Experiment 1, Japanese participants were asked to solve 100 multiple-choice A:B::C:D analogy problems (e.g., skeleton: bone:: tornado: wind) in their first language, Japanese (L1). In this experiment, participants also rated the difficulty and creativity of problems. In Experiment 2, Japanese participants completed the same tasks, but the problems were shown in their second language, English (L2). The results showed that problems presented in L1 elicited higher accuracies and faster response times than in L2. A significant interaction was found between languages (L1/L2) and the category of problems which indicates that finding a perceptual similarity (e.g., the shape image of word concepts) with verbal stimuli in L2 is more challenging than in L1. Moreover, our results on response times indicated that processing relations between words would be carried out in L1 without any specific instruction while it would not be completed in L2 possibly due to the cognitive demand related to lexical processing. Considering these results, it is advisable in an educational setting to provide L2 learners with enough time and explicit instruction on understanding word relationships when forming analogies.
Risk assessment of antibiotic residues and resistance profile of E. coli in typical rivers of Sichuan, China
The presence and distribution of antibiotics and antibiotic resistance genes (ARGs) in rivers have attracted significant global concern. However, research on the contamination of typical rivers in Sichuan Province, China, remains limited. This study aimed to assess the residual levels of antibiotics across 42 national and provincial monitoring sites in nine rivers within Sichuan using UPLC-MS/MS. Ecological risk levels were evaluated through established risk assessment methods, and antibiotic resistance in Escherichia coli(E.coli) isolated from these waters was determined using the Kirby-Bauer disk diffusion method. Additionally, redundancy analysis (RDA) was conducted to explore the impact of residual antibiotics on the microbial community structure in the Minjiang River basin. Antibiotics were detected in all nine rivers studied, with the Minjiang, Tuojiang, and Jialingjiang rivers exhibiting particularly severe contamination, with concentrations ranging from 0.29 to 2233.71 ng/L. The level of antibiotic pollution in the Sichuan Basin was significantly higher than in other regions of Sichuan, likely due to the area’s high population density. Furthermore, 9.77% of E. coli isolates from the nine rivers exhibited antibiotic resistance, with over 5.8% demonstrating multidrugs resistance. Norfloxacin, amoxicillin, ampicillin, and tetracycline were identified as the primary contributors to the high ecological risk at 26 of the 42 monitoring sites. A strong correlation was observed between residual antibiotics and changes in microbial community structure. These findings provide critical insights into the distribution of antibiotics and ARGs in the rivers of Sichuan Province and highlight the urgent need for targeted strategies to mitigate antibiotic pollution. Addressing this issue is essential to protect both ecological integrity and public health.
Spatio-temporal distribution of foot and mouth disease outbreaks in Western Amhara region from January 2018 to June 2023
Foot and mouth disease (FMD) is a contagious and economically important viral disease of cloven hoofed animals caused by FMD virus. This retrospective study was conducted to determine the spatio-temporal distribution, estimate the morbidity and case fatality of FMD outbreaks in Western Amhara region of Ethiopia from January 2018 to June 2023. The FMD outbreaks reported to Bahir Dar regional laboratory and confirmed by Sandwich ELISA were used for this study. A total of 164 FMD outbreaks were reported in Western Amhara region of Ethiopia between 2018 and 2023. The highest and lowest number of FMD outbreaks were reported in 2022 (n = 42 outbreaks) and 2018 (n = 9), respectively; however, there was no statistically significant difference in the occurrence of FMD outbreaks between years (p = 0.224). There was no significant difference in case fatality and morbidity rates between years (p> 0.05). Based on months, high number of outbreaks were reported during January (n = 32) across all years and the lowest during April, June and September (n = 3 for each district). There was statistically significant difference in the occurrence of FMD outbreaks between months (p < 0.001). On average, 13.66 FMD outbreaks were reported in each month. All administrative zones in Western Amhara region reported more than one FMD outbreaks during January 2018 –June 2023. The highest and lowest outbreaks were reported from East Gojjam Zone (62 outbreaks/6 district years), and Bahirdar Special Zone and Gondar Town (2 outbreaks for each district). There was no statistically significant difference in the occurrence of FMD outbreaks between the administrative zones (p > 0.05). District wise, the highest and lowest number of FMD outbreaks were reported from Goncha Siso district (n = 14) and Banja, Simada, Zigem, Machakel, Debre Elias and Debark (with one outbreak in each district). This study indicated that FMD outbreaks regular occurs in Western Amhara region. To reduce the occurrence and spreading, animal movement and transport should be controlled, and vaccination should be implemented regularly.
Correction: Integration of metabolomics and transcriptomics provides insights into the molecular mechanism of temporomandibular joint osteoarthritis
Effects of trauma-related amputations in children on caregivers: An exploratory descriptive study in a developing country
Amputation in children is rare. However, in recent times, amputation in children has increased and trauma is the leading cause in Ghana. Few studies on the effects of amputation on caregivers particularly of children are available. This study aimed to explore the effects of trauma-related amputations in children on caregivers using qualitative descriptive phenomenological approach. In-depth interviews were conducted with semi-structured interview guide. Ten (10) informal caregivers were purposively selected from the trauma registry of a tertiary facility in Ghana. Data were analyzed manually using the thematic approach described by Collaizi. The findings revealed that trauma-related amputations in children affect the work-role, social life, finances and mental health of the caregivers. Provision of counselling services to address the mental health needs of caregivers and decentralization of orthopaedic and rehabilitation services would lessen the burden of caregiving.
WISIT vaccines based on IL-31-derived peptides as a novel therapeutic approach for chronic pruritic dermatoses
Vaccines are a promising therapy for the treatment of chronic conditions such as pruritus. IL-31 has been identified as an important mediator of itch. By targeting IL-31 signaling with immunotherapy, CP can be effectively alleviated. However, self-antigens such as IL-31 are highly tolerated, which has rendered conventional conjugate vaccines (CCVs) ineffective at generating sufficient antibody (Ab) responses to alleviate CP. Novel Win the Skin Immune System Trick (WISIT) vaccines however have been shown to induce substantially stronger Ab responses than CCVs in Parkinson’s Disease, and so may be capable of overcoming IL-31 tolerance to effectively treat CP. In this report, WISIT vaccines presenting ten different IL-31-specific peptides were compared to CCVs presenting the same peptides. Multiple response parameters were assessed, including Ab titers induced, avidity of these Abs, and IL-31 signaling inhibition. Results demonstrated that WISIT vaccines outperform CCVs across all investigated metrics, culminating in the identification of 3 promising candidate WISIT vaccines to be taken forward for further clinical development. This report thus provides evidence that the improved immunogenicity of WISIT vaccines is not disease-specific and that WISIT vaccines may also be translated to treat dermatological disorders. Further preclinical development will be necessary to prepare the identified IL-31 targeting WISIT vaccine candidates for clinical testing.
Assessing physical literacy and establishing normative reference curves for 8–12-year-old children from South Punjab, Pakistan: The PAK-IPPL cross-sectional study
Background Physical literacy (PL) encompasses an individual’s motivation, confidence, physical competence, and knowledge, all of which foster lifelong engagement in physical activities. In developing countries like Pakistan, there is a pressing need to assess PL status using culturally valid tools. This study aims to evaluate PL among children aged 8–12 in South Punjab, Pakistan while developing normative reference curves and exploring factors influencing PL. Methods A cross-sectional study was conducted with 1,360 students (mean age = 10.00, SD = 1.41 years) from 85 schools, using a culturally adapted and validated version of the CAPL-2 tool. The CAPL-2 scoring system was validated to align with the population and cultural context. Statistical analyses, including t-tests, Chi-squared tests, Pearson’s correlation, multivariate logistic regression, and Classification and regression tree methods, were performed to identify factors associated with PL classifications, with significance set at p < 0.05. The Generalized Additive Models for Location, Scale, and Shape were used to create age- and sex-specific PL normative reference curves. Result The study revealed significant influences of gender, socioeconomic status (SES), and locality on PL. Boys consistently scored higher in PL across all domains compared to girls, with significant differences (p < 0.001) in all but the knowledge and understanding domain (p = 0.160). Boys’ PL scores were 6% higher overall, with a 7% and 5% advantage in the daily behavior and physical competence domains, respectively. Children from low SES and rural settings exhibited significantly higher PL scores than their middle/high SES and urban counterparts (p < 0.001). Walking to school was positively correlated with higher PL scores, while children traveling by car had the lowest scores (p < 0.001). Anthropometric differences between genders were noted, further emphasizing the disparities in physical competence. Most participants (71.6%) fell into the "Beginning" or "Progressing" PL categories, with females predominantly in these lower stages. Conclusion This study reveals that gender, SES, and locality significantly impact PL among children in South Punjab, Pakistan. Boys, lower SES groups, and rural children showed higher PL scores, with everyday activities like walking to school positively contributing to PL development. These findings emphasize the need for targeted, demographically sensitive interventions to enhance PL in the region.
Prey depletion, interspecific competition, and the energetics of hunting in endangered African wild dogs, <i>Lycaon pictus</i>
Large herbivores are in decline in much of the world, including sub-Saharan Africa, and true apex carnivores like the lion ( Panthera leo ) decline in parallel with their prey. As a consequence, competitively subordinate carnivores like the African wild dog ( Lycaon pictus ) are simultaneously experiencing a costly reduction in resources and a beneficial reduction in dominant competitors. The net effect is not intuitively obvious, but wild dogs’ density, survival, and reproduction are all low in areas that are strongly affected by prey depletion. To assess whether these correlations are causal, we tested the hypothesized mechanism, using data from 13 wild dog packs in two ecosystems to relate the energetic costs and benefits of hunting to variation in prey density, while controlling for the effects of local lion density, pack size, the number of dependent pups, and the level of protection. All of these variables affected the energetic costs and benefits of hunting. In areas with low prey density, the magnitude of movements and vectorial dynamic body acceleration (a measure of energy expenditure) both increased, the mass of killed prey decreased, and the number of kills per day did not change detectably. Programs to reduce or reverse the decline of large herbivore populations should be an effective means of improving the status of endangered subordinate competitors like the wild dog, and should be a high priority. Our results demonstrate the utility of research that integrates data from biomonitoring with direct, long-term observation of endangered species, their competitors, and their resources.