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Contrafreeloading (CFL) refers to animals’ tendency to prefer obtaining food through effort rather than accessing food that is freely available. Researchers have proposed various hypotheses to explain this intriguing phenomenon, but few studies have provided a comprehensive analysis of the factors influencing this behaviour. In this study, we observed the choice of alternative food containers in budgerigars (Melopsittacus undulatus) to investigate their CFL tendencies and the effects of pre-training, food deprivation, and effort required on the CFL tasks. The results showed that budgerigars did not exhibit significant difference in their first choices or the time interacting with less challenging versus more challenging food containers. Moreover, when evaluating each budgerigar’s CFL level, only half of them were identified as strong contrafreeloaders. Thus, we suggest that budgerigars exhibit an intermediate CFL level that lies somewhere between a strong tendency and the absence of such behaviour. Furthermore, we also found that food-deprived budgerigars tended to select less challenging food containers, and pre-trained budgerigars were more likely to choose highly challenging food containers than moderately challenging food containers, which means that the requirement of only a reasonable effort (access to food from moderately challenging food containers in this study) and the experience of pre-training act to enhance their CFL levels, whereas the requirement of greater effort and the experience of food deprivation act to decrease their CFL levels. Studying animal CFL can help understand why animals choose to expend effort to obtain food rather than accessing it for free, and it also has implications for setting feeding environments to enhance the animal welfare of captive and domesticated animals.
Language control in the bilingual brain has remained in the limelight of research over the past decades. However, the mechanisms underlying bilingual language control may be more intricate than typically assumed due to the hierarchical nature of language. This study aimed to investigate the dynamics of bilingual language control at the phonetic level. Participants, who were speakers of Chinese, English and German, named the letters of the alphabet in English (L2) or German (L3) following an alternating language-switching paradigm. Two sets of letters were selected, differing in the phonological similarity of their pronunciation across the two languages, thereby allowing the exploration of cross-language phonological influences. Each participant completed two sessions of letter-naming tasks. In one session, seven phonologically similar letters were randomly repeated either in single-language blocks or in alternate-language blocks. In the other session, seven phonologically dissimilar letters were similarly manipulated. The results indicated local inhibition, reflected by switch costs and global inhibition, reflected by mixing costs. Reversed language dominance, another indicator of global inhibition, was not observed. However, there was a tendency for larger global inhibition to be applied to the more dominant language. Moreover, there was significantly faster naming for phonologically similar letters compared to dissimilar ones, suggesting a facilitation effect for both English and German, irrespective of whether letter naming occurred in single- or alternate-language blocks. These findings provided evidence for the role of inhibitory and facilitative mechanisms at the phonetic level, suggesting language-specific control in the bilingual brain and underscoring the complexity and dynamics of managing language control across multiple levels of processing.
Previous studies have linked social behaviors to COVID-19 risk in the general population. The impact of these behaviors among healthcare personnel, who face higher workplace exposure risks and possess greater prevention awareness, remains less explored.
Design:
We conducted a Prospective cohort study from December 2021 to May 2022, using monthly surveys. Exposures included (1) a composite of nine common social activities in the past month and (2) similarity of social behavior compared to pre-pandemic. Outcomes included self-reported SARS-CoV-2 infection (primary)and testing for SARS-CoV-2 (secondary). Mixed-effect logistic regression assessed the association between social behavior and outcomes, adjusting for baseline and time-dependent covariates. To account for missed surveys, we employed inverse probability-of-censoring weighting with a propensity score approach.
Setting:
An academic healthcare system.
Participants:
Healthcare personnel.
Results:
Of 1,302 healthcare personnel who completed ≥2 surveys, 244 reported ≥1 positive test during the study, resulting in a cumulative incidence of 19%. More social activities in the past month and social behavior similar to pre-pandemic levels were associated with increased likelihood of SARS-CoV-2 infection (recent social activity composite: OR = 1.11, 95% CI 1.02–1.21; pre-pandemic social similarity: OR = 1.14, 95% CI 1.07–1.21). Neither was significantly associated with testing for SARS-CoV-2.
Conclusions:
Healthcare personnel social behavior outside work was associated with a higher risk for COVID-19. To protect the hospital workforce, risk mitigation strategies for healthcare personnel should focus on both the community and workplace.
The incidence of obesity-related glomerulopathy (ORG) is rising worldwide with very limited treatment methods. Paralleled with the gut–kidney axis theory, the beneficial effects of butyrate, one of the short-chain fatty acids (SCFA) produced by gut microbiota, on metabolism and certain kidney diseases have gained growing attention. However, the effects of butyrate on ORG and its underlying mechanism are largely unexplored. In this study, a mice model of ORG was established with a high-fat diet feeding for 16 weeks, and sodium butyrate treatment was initiated at the 8th week. Podocyte injury, oxidative stress and mitochondria function were evaluated in mice kidney and validated in vitro in palmitic acid-treated-mouse podocyte cell lines. Further, the molecular mechanisms of butyrate on podocytes were explored. Compared with controls, sodium butyrate treatment alleviated kidney injuries and renal oxidative stress in high-fat diet-fed mice. In mouse podocyte cell lines, butyrate ameliorated palmitic acid-induced podocyte damage and helped maintain the structure and function of the mitochondria. Moreover, the effects of butyrate on podocytes were mediated via the GPR43-Sirt3 signal pathway, as evidenced by the diminished effects of butyrate with the intervention of GPR43 or Sirt3 inhibitors. In summary, we conclude that butyrate has therapeutic potential for the treatment of ORG. It attenuates high-fat diet-induced ORG and podocyte injuries through the activation of the GPR43-Sirt3 signalling pathway.
This study explores the integration of generative artificial intelligence (GenAI) in informal digital learning of English (IDLE) practices, focusing on its potential to enhance language learning outcomes and addressing the technological challenges language teachers face in utilising AI-based tools to facilitate second language acquisition. Based on the research context of IDLE and holistic learning ecology and drawing on the theoretical frameworks of technological pedagogical and content knowledge and social cognitive theory, we performed a mixed-methods investigation with an empirical experiment to assess the effectiveness of GenAI followed by semi-structured interviews. The results suggest that the GenAI-mediated IDLE practices effectively improve college students’ oral proficiency in English from both technological and humanistic perspectives. However, results also indicate that the GenAI conversational partner alone is not adequate to provoke continuous extramural GenAI-mediated IDLE practices. We discuss the theoretical and pragmatic significance of GenAI-mediated IDLE in educational equity and reformation.
Observational studies have shown a controversial relationship between dietary fat intake and Alzheimer's disease, and the causal effects are unclear.
Aims
To assess the causal effects of total fat, saturated fat and polyunsaturated fat (PUF) intakes on the risk of Alzheimer's disease.
Method
A two-sample Mendelian randomisation analysis was performed using genome-wide association study summary statistics on different types of fat intake from UK Biobank (n = 51 413) and on late-onset Alzheimer's disease (LOAD; 4282 cases, n = 307 112) and all forms of Alzheimer's disease (6281 cases, n = 309 154) from the FinnGen consortium. In addition, a multivariable Mendelian randomisation (MVMR) analysis was conducted to estimate the effects independent of carbohydrate and protein intakes.
Results
Genetically predicted per standard deviation increase in the total fat and saturated fat intakes were associated with 44 and 38% higher risks of LOAD (total fat: odds ratio = 1.44, 95% CI 1.03–2.02; saturated fat: odds ratio = 1.38, 95% CI 1.002–1.90; P = 0.049). The associations remained significant in the MVMR analysis (total fat: odds ratio = 3.31, 95% CI 1.74–6.29; saturated fat: odds ratio = 2.04, 95% CI 1.16–3.59). Total fat and saturated fat intakes were associated with a higher risk of all forms of Alzheimer's disease in the MVMR analysis (total fat: odds ratio = 2.09, 95% CI 1.22–3.57; saturated fat: odds ratio = 1.60, 95% CI 1.01–2.52). The PUF intake was not associated with LOAD or all forms of Alzheimer's disease.
Conclusions
This study indicated that total dietary fat intake, especially saturated fat, contributed to the risk of Alzheimer's disease, and the effects were independent of other nutrients. These findings informed prevention strategies and management for Alzheimer's disease directly towards reducing dietary saturated fat intake.
Modern studies suggest that the upper ocean heat content (OHC) in the tropical Indian Ocean (TIO) is a better qualitative predictor of the Indian summer monsoon rainfall (ISMR). But it is still unknown how the OHC is mechanically linked to ISMR and whether it can be applied to long-term climate changes. By analyzing reanalysis datasets across the 20th century, we illustrate that in contrast to those anomalies associated with stronger ISM westerlies, higher ISMR is accompanied with summer surface high pressure and east wind anomalies from the South China Sea to the Bay of Bengal (BOB), and is loosely related to increased western TIO OHC during decayed phases of positive Indian Ocean dipole (IOD) and of El Niño. Except for 1944–1968 AD, this interannually lagged ISMR response to winter OHC is insignificant, probably suppressed by those simultaneous effects of positive IOD and El Niño on ISMR. In our paleoclimatic simulations, this modern observed lagged response is interrupted by seasonally reversed insolation anomalies at the 23,000-year precessional band. Our sensitivity experiments further prove that, the ISMR can be simultaneously reduced by positive IOD-like summer OHC anomalies both for modern and precessional situations. This damping effect is mainly contributed by the warmer western TIO that triggers anomalous surface high pressure, easterly winds, and drastically reduced rainfall from BOB to Arabian Peninsula, but with slightly increased rainfall in the northern ISM region. And the cooler southeastern TIO will only moderately increase rainfall in the southern ISM region.
As the need for collaboration across multiple organizations to deal with complex social issues such as poverty, crime, and public health grows, Public–Private Partnership (PPP) is of increasing importance. However, little is known about when and why private firms engage in such partnerships. Drawing on upper-echelon theory and the information-processing perspective, we highlight the importance of institutional knowledge and information embedded in CEO cross-sector work experience. We argue that such tacit knowledge and information enables CEOs to better identify the potential risks associated with PPPs. Consequently, CEOs with cross-sector work experience tend to be more cautious in participating in such partnerships, especially in developing economies like China, where private actors face greater information incompleteness concerning post-collaboration hazards due to the government's selective disclosure. Moreover, we develop a multi-moderator framework in which regional marketization and political connection alter the main effect by serving as supplementary information channels for private actors. A panel dataset of Chinese private listed firms from 2013 to 2021 provides strong support for our hypotheses. This study contributes to our understanding of the micro-foundation of PPP formation and draws attention to CEOs’ prior career experiences in different organizational forms.
Whether material deprivation-related childhood socio-economic disadvantages (CSD) and care-related adverse childhood experiences (ACE) have different impacts on depressive symptoms in middle-aged and older people is unclear.
Methods
In the Guangzhou Biobank Cohort Study, CSD and ACE were assessed by 7 and 5 culturally sensitive questions, respectively, on 8,716 participants aged 50+. Depressive symptoms were measured by 15-item Geriatric Depression Scale (GDS). Multivariable linear regression, stratification analyses, and mediation analyses were done.
Results
Higher CSD and ACE scores were associated with higher GDS score in dose-response manner (P for trend <0.001). Participants with one point increment in CSD and ACE had higher GDS score by 0.11 (95% confidence interval [CI], 0.09–0.14) and 0.41 (95% CI, 0.35–0.47), respectively. The association of CSD with GDS score was significant in women only (P for sex interaction <0.001; women: β (95% CI)=0.14 (0.11–0.17), men: 0.04 (−0.01 to 0.08)). The association between ACE and GDS score was stronger in participants with high social deprivation index (SDI) (P for interaction = 0.01; low SDI: β (95% CI)=0.36 (0.29–0.43), high SDI: 0.64 (0.48–0.80)). The proportion of association of CSD and ACE scores with GDS score mediated via education was 20.11% and 2.28%.
Conclusions
CSD and ACE were associated with late-life depressive symptoms with dose-response patterns, especially in women and those with low adulthood socio-economic status. Education was a major mediator for CSD but not ACE. Eliminating ACE should be a top priority.
Cowl-induced incident shock wave/boundary layer interactions (ISWBLIs) under the influence of shoulder expansion represent one of the dominant phenomena in supersonic inlets. To provide a more comprehensive understanding of how an expansion corner affects the ISWBLI, a detailed experimental and analytical study is performed in a Mach 2.73 flow in this work. Pressure measurement, schlieren photography and surface oil-flow visualisation are used to record flow features, including the pressure distribution, separation extent and surface-flow topological structures. Our results reveal three types of ISWBLIs influenced by the expansion corner. When the shock intensity is weak, the separation is small scale with the expansion waves emanating from the expansion corner. This is the first type of expansion-corner-affected ISWBLI (EC-ISWBLI). When the incident shock wave is strong, large-scale separation occurs, accompanied by the disappearance of expansion waves, forming the second type of EC-SWBLI. The expansion corner induces a ‘lock-in’ effect in which the separation onset is consistently locked near the expansion corner regardless of the incident shock intensity and impingement position. The third type of EC-ISWBLI occurs when the shock is sufficiently strong and the impingement point is close to the expansion corner. In this interaction, the ‘lock-in’ effect ceases to manifest. Moreover, a shock polar-incorporating inviscid model is employed to elucidate the shock patterns. Two criteria are established by combining free interaction theory with this model. The first criterion provides valuable insights into the evolution of separations with a minimal overall pressure rise and the second criterion determines the threshold for the occurrence of the ‘lock-in’ effect.
Pulmonary atresia with intact ventricular septum and critical pulmonary stenosis usually have to undergo treatment in the neonatal period. Compared to traditional surgical intervention, catheter-based cardiac interventions may achieve similar or superior outcomes for neonates with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, there is limited literature on anaesthesia techniques, challenges, and risks associated with cardiac catheterisation in this population.
Methods:
This article retrospectively analysed the clinical data of pulmonary atresia with intact ventricular septum and critical pulmonary stenosis neonates who were treated with interventional cardiac catheterisation in our hospital from January 2015 to October 2022. Clinical outcomes considered were haemodynamic or pulse oxygen saturation instability, vasoactive requirements, prolonged intubation (>24 h postoperatively), and cardiovascular adverse events.
Results:
A total of 63 patients met the inclusion criteria. All patients survived the intervention. Among the patients with critical pulmonary stenosis, 40 successfully received percutaneous balloon pulmonary valvuloplasty, while three patients received ductal stenting due to moderate right ventricular dysplasia at the same time. For patients with pulmonary atresia with intact ventricular septum, 17 of the 23 patients successfully underwent percutaneous pulmonary valve perforation and percutaneous balloon pulmonary valvuloplasty. Of these, five patients underwent ductal stenting due to unstable pulmonary blood flow. Three patients only underwent ductal stenting. In addition, three patients received hybrid therapy.
Conclusions:
There are various clinical techniques and risk challenges in the interventional cardiac catheterisation of neonatal pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, by mastering the physiological and pathophysiological characteristics of the disease, adequately preparing for the perioperative period, and predicting the procedure process and potential complications, anaesthesia and surgical risks can be effectively managed.
Three-dimensional effects of sidewalls on the low-frequency unsteadiness of the shock-wave/boundary-layer interaction (SBLI) are of academic and practical importance but not yet well understood. Considerable attention has been paid to the viscous effect of sidewalls, whereas the potential inviscid confinement effect of sidewalls has received little attention. The present work provides experimental evidence of multiscale spanwise travelling waves crossing the separation front under the confinement of sidewalls. Global pressure measurements were made for a sidewall-confined 24$^\circ$ compression ramp interaction in Mach-2.83 flow using fast-responding pressure-sensitive paint. The unsteady pressure in a statistically two-dimensional intermittent region suggests that in addition to the canonical streamwise oscillation, the separation front exhibits significant low-frequency, multiscale spanwise distortion. Modal analysis further reveals that multiscale spanwise unsteadiness has higher intensity and frequency than the streamwise oscillation. Such strong spanwise unsteadiness calls attention to the low-frequency unsteadiness in previous sidewall-confined SBLI experiments and encourages further study on the mechanism of the confinement effect.
This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.
This study aimed to evaluate the methodological quality of existing meta-analyses (MA) and the quality of evidence for outcome indicators to provide an updated overview of the evidence concerning the therapeutic efficacy of the Mediterranean diet (MD) for various types of CVD.
Design:
We conducted comprehensive searches of PubMed, Cochrane Library, and Embase databases. The quality of the MA was assessed using the A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) checklist, while the Grading of Recommendations Assessment, Development and Evaluation (GRADE) evidence evaluation system was employed to evaluate the quality of evidence for significant outcomes.
Setting:
The CVD remains a significant contributor to global mortality. Multiple MA have consistently demonstrated the efficacy of medical interventions in managing CVD. However, due to variations in the scope, quality and outcomes of these reviews, definitive conclusions are yet to be established.
Participants:
This study included five randomized trials and twelve non-randomized studies, with a combined participant population of 716 318.
Results:
The AMSTAR 2 checklist revealed that 54·55 % of the studies demonstrated high quality, while 9·09 % exhibited low quality, and 36·36 % were deemed critically low quality. Additionally, there was moderate evidence supporting a positive correlation between MD and CHD/acute myocardial infarction, stroke, heart failure, cardiovascular events, coronary events and major adverse cardiovascular events.
Conclusions:
This study indicates that although recognizing the potential efficacy of MD in managing CVD, the quality of the methodology and the evidence for the outcome indicators remain unsatisfactory.
As an environmental factor, temperature impacts the distribution of species and influences interspecific competition. The molecular chaperones encoded by small heat shock proteins (sHsps) are essential for rapid, appropriate responses to environmental stress. This study focuses on Hsp20.8, which encodes a temperature-responsive sHsp in Liriomyza trifolii, an insect pest that infests both agricultural and ornamental crops. Hsp20.8 expression was highest at 39℃ in L. trifolii pupae and adults, and expression levels were greater in pupae than in adults. Recombinant Hsp20.8 was expressed in Escherichia coli and conferred a higher survival rate than the empty vector to bacterial cells exposed to heat stress. RNA interference experiments were conducted using L. trifolii adults and prepupae and the knockdown of Hsp20.8 expression increased mortality in L. trifolii during heat stress. The results expand our understanding of sHsp function in Liriomyza spp. and the ongoing adaptation of this pest to climate change. In addition, this study is also important for predicting the distribution of invasive species and proposing new prevention and control strategies based on temperature adaptation.
In preparation for an experiment with a laser-generated intense proton beam at the Laser Fusion Research Center at Mianyang to investigate the 11B(p,α)2α reaction, we performed a measurement at very low proton energy between 140 keV and 172 keV using the high-voltage platform at the Institute of Modern Physics, Lanzhou. The aim of the experiment was to test the ability to use CR-39 track detectors for cross-section measurements and to remeasure the cross-section of this reaction close to the first resonance using the thick target approach. We obtained the cross-section σ = 45.6 ± 12.5 mb near 156 keV. Our result confirms the feasibility of CR-39 type track detector for nuclear reaction measurement also in low-energy regions.
Modified kaolinites possess excellent adsorption properties and, therefore, are regarded widely as potential catalytic components. The use of modified kaolinites as a catalytic component for Fischer–Tropsch synthesis (FTS) has remained unexplored, however. In the current study, delaminated and pit-rich nano-kaolinite was prepared via acid treatment of N-methylformamide (NMF)-intercalated kaolinite (intercalation-etching strategy), and was used as a support to prepare a cobalt-based FTS catalyst (denoted as 15%-Co-HNKln). Compared with other FTS catalysts, the supports for which were raw kaolinite or directly acid-treated kaolinite, the 15%-Co-HNKln showed several advantages such as large specific surface area, dispersed Co particles with small particle size, more new active sites, and significant surface acidity. Given the aforementioned advantages, the 15%-Co-HNKln catalyst demonstrated very good FTS performance. Compared with that of the raw kaolinite-supported FTS catalyst, the CO conversion rate and C5–C12 hydrocarbon selectivity of 15%-Co-HNKln increased by 20% and 15%, respectively.
The effects of magnetic vortex acceleration (MVA) are investigated with two-dimensional particle-in-cell (PIC) simulations by laser interaction with near-critical density (NCD) plasma inside a hollow conical plasma. Energetic and collimated proton beams can be accelerated by a longitudinal charge-separation field. Energetic protons with a peak energy of 220 MeV are produced in PIC simulations. Compared with a uniform NCD plasma, both the cutoff energy and collimation of proton beams are improved remarkably. Furthermore, the influence of different gap sizes of cone tip is taken into account. For optimizing magnetic vortex acceleration, the gap size of the cone tip is suggested to match the focal spot size of laser pulse.
In order to establish a compact all-optical Thomson scattering source, experimental studies were conducted on the 45 TW Ti: sapphire laser facility. By including a steel wafer, mixed gas, and plasma mirror into a double-exit jet, several mechanisms, such as shock-assisted ionization injection, ionization injection, and driving laser reflection, were integrated into one source. So, the source of complexity was remarkably reduced. Electron bunches with central energy fluctuating from 90 to 160 MeV can be produced. Plasma mirrors were used to reflect the driving laser. The scattering of the reflected laser on the electron bunches led to the generation of X-ray photons. Through comparing the X-ray spots under different experimental conditions, it is confirmed that the X-ray photons are generated by Thomson scattering. For further application, the energy spectra and source size of the Thomson scattering source were measured. The unfolded spectrum contains a large amount of low-energy photons besides a peak near 67 keV. Through importing the electron energy spectrum into the Monte Carlo simulation code, the different contributions of the photons with small and large emitting angles can be used to explain the origin of the unfolded spectrum. The maximum photon energy extended to about 500 keV. The total photon production was 107/pulse. The FWHM source size was about 12 μm.
Innovations in horse equipment during the early Middle Ages provided advantages to societies from the steppes, reshaping the social landscape of Eurasia. Comparatively little is known about the precise origin of these crucial advances, although the available evidence points to early adoption in East Asia. The authors present new archaeological discoveries from western and northern Mongolia, dating to the fourth and fifth centuries AD, including a wooden frame saddle with horse hide components from Urd Ulaan Uneet and an iron stirrup from Khukh Nuur. Together, these finds suggest that Mongolian groups were early adopters of stirrups and saddles, facilitating the expansion of nomadic hegemony across Eurasia and shaping the conduct of medieval mounted warfare.