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Shock-tube experiments on Richtmyer–Meshkov (RM) instability at a perturbed SF$_6$ layer surrounded by air, induced by a cylindrical divergent shock, are reported. To explore the effects of reverberating waves and interface coupling on instability growth, gas layers with various shapes are created: unperturbed inner interface and sinusoidal outer interface (case US); sinusoidal inner and outer interfaces that have identical phase (case IP); sinusoidal inner and outer interfaces that have opposite phase (case AP). For each case, three thicknesses are considered. Results show that reverberating waves inside the layer dominate the early-stage instability growth, while interface coupling dominates the late-stage growth. The influences of waves on divergent RM instability are more pronounced than the planar and convergent counterparts, which are estimated accurately based on gas dynamics theory. Both the wave influence and interface coupling depend heavily on the layer shape, leading to diverse growth rates: the quickest growth for case AP, medium growth for case US, the slowest growth for case IP. In particular, for the IP case, there exists a critical thickness below which the instability growth is suppressed by both the reverberating waves and interface coupling. This provides an efficient way to modulate the growth of divergent RM instability. It is found that divergent RM instability involves weak nonlinearity and strong interface coupling such that the linear theory of Mikaelian (Phys. Fluids, vol. 17, 2005, 094105) can well reproduce the instability growth at late stages for all cases. This constitutes the first experimental confirmation of the Mikaelian theory.
To solve the problem of the leakage of phase-change materials and expand the application of clay minerals in the field of phase-change materials, illite and paraffin wax were used for the first time as a new binary hybrid core material with silica as the wall material. Phase-change microcapsules were prepared using the sol–gel method and successfully applied in silicone rubber foams. Differential scanning calorimetry showed that the microcapsules had a melting temperature of 62.99°C and a latent heat capacity of 98.24 J g–1, indicating their good heat-storage capacity. Furthermore, the effectiveness of using illite as a filler for preventing paraffin leakage was demonstrated through 200 thermal cycling tests, which demonstrated a leakage rate of only 2.6% compared to 3.2% exhibited by microcapsules without illite.
Students’ attention deficit has a negative impact on their learning and development. In traditional teaching environments, students with attention deficit often face problems such as difficulty concentrating, distraction, difficulty maintaining sustained attention, and controlling attention. At the same time, teaching reform has become a focus of attention in the education industry, aiming to improve students’ learning outcomes and cultivate comprehensive development abilities.
Subjects and Methods
The study adopts an experimental group and a control group design. The experimental group received teaching reform measures, including improving teaching methods, increasing interaction and cooperative learning, etc; The control group continued to use traditional teaching methods. The study collected data on students’ attention deficit scores and academic performance, and used SPSS 22.0 statistical software for data processing and analysis to compare the differences between the experimental group and the control group.
The attention deficit score of the experimental group students was significantly reduced, and the SPSS22.0 statistical method verified that the difference between the experimental group and the control group was statistically significant (P<0.05). In addition, the academic performance of the experimental group students has also significantly improved, such as improving exam scores and increasing interest in learning.
The research results indicate that teaching reform has a positive impact on students’ attention deficit. Improving teaching methods and increasing interaction and collaborative learning can help improve students’ concentration and attention regulation abilities.
Key Education Reform Project of Hainan Provincial Department of Education (No. Hnjg2022ZD-4220); High-level Talents Project of Hainan Provincial Natural Science Foundation (No. 621RC602); Major Special Project of Sanya University (No. USY22XK-04); Key Research and Development Project of Hainan Province (No. ZDYF2023GXJS007); School-level Project of Sanya University (No. USYYB22-07).
To examine the associations of pregnant women’s dietary and sedentary behaviours with their children’s birth weight.
Secondary data analysis was conducted using data from a randomised controlled trial, Communicating Healthy Beginnings Advice by Telephone, conducted in Australia. Information on mothers’ socio-demographics, dietary and sedentary behaviours during pregnancy was collected by telephone survey at the third trimester. Birth weight data were extracted from the child’s health record book. Multinomial logistic regression models were built to examine the associations of pregnant women’s dietary and sedentary behaviours with children’s birth weight.
Pregnant women and their children.
A total of 1132 mother–child dyads were included in the analysis. The majority of infants (87 %, n 989) were of normal birth weight (2500 g to <4000 g), 4 % (n 50) had low birth weight (<2500 g) and 8 % (n 93) had macrosomia (≥4000 g). Mothers who ate processed meat during pregnancy were more likely to have macrosomia (adjusted risk ratio (ARR) 1·80, 95 % CI (1·12, 2·89)). The risk of macrosomia decreased as the number of dietary recommendations met by mothers increased (ARR 0·84, 95 % CI (0·71, 0·99)). Children’s birth weight was not associated with mothers’ sedentary time. Children’s low birth weight was not associated with mothers’ dietary and sedentary behaviours during pregnancy.
Maternal consumption of processed meat during pregnancy was associated with an increased risk of macrosomia. Increasing number of dietary recommendations met by mothers was associated with a lower risk of macrosomia. The findings suggested encouraging pregnancy women to meet dietary recommendation will benefit children’s birth weight.
Longitudinal studies on the variations of phenotypic and genotypic characteristics of K. pneumoniae across two decades are rare. We aimed to determine the antimicrobial susceptibility and virulence factors for K. pneumoniae isolated from patients with bacteraemia or urinary tract infection (UTI) from 1999 to 2022. A total of 699 and 1,267 K. pneumoniae isolates were isolated from bacteraemia and UTI patients, respectively, and their susceptibility to twenty antibiotics was determined; PCR was used to identify capsular serotypes and virulence-associated genes. K64 and K1 serotypes were most frequently observed in UTI and bacteraemia, respectively, with an increasing frequency of K20, K47, and K64 observed in recent years. entB and wabG predominated across all isolates and serotypes; the least frequent virulence gene was htrA. Most isolates were susceptible to carbapenems, amikacin, tigecycline, and colistin, with the exception of K20, K47, and K64 where resistance was widespread. The highest average number of virulence genes was observed in K1, followed by K2, K20, and K5 isolates, which suggest their contribution to the high virulence of K1. In conclusion, we found that the distribution of antimicrobial susceptibility, virulence gene profiles, and capsular types of K. pneumoniae over two decades were associated with their clinical source.
The latest international guideline recommended the add-on therapy of ezetimibe and PCSK9 inhibitors in selected people for the secondary prevention of cardiovascular diseases (CVDs). However, it remains unclear whether these regimens fit the Chinese healthcare system economically.
Based on the Chinese context, this simulation study evaluated four therapeutic strategies including the high-dose statin-only group, ezetimibe plus statin group, PCSK9 inhibitors plus statin group, and PCSK9 inhibitors plus ezetimibe plus statin group. The team developed a Markov model to estimate the incremental cost-effectiveness ratio (ICER). With each 1-yr cycle, the simulation subjects could have nonfatal cardiovascular events (stroke and/or myocardial infarction) or death (vascular or nonvascular death event) with a follow-up duration of 20 yr. Cardiovascular risk reduction was gathered from a network meta-analysis, and cost and utility data were gathered from hospital databases and published research.
For Chinese adults receiving high-dose statins for secondary prevention of CVDs, the ICER was US$68,910 per quality-adjusted life year (QALY) for adding PCSK9 inhibitors, US$20,242 per QALY for adding ezetimibe, US$51,552 per QALY for adding both drugs. Given a threshold of US$37,655 (three times of Chinese GDP), the probability of cost-effectiveness is 2.9 percent for adding PCSK9 inhibitors, 53.1 percent for adding ezetimibe, and 16.8 percent for adding both drugs. To meet the cost-effectiveness, an acquisition price reduction of PCSK9 inhibitors of 33.6 percent is necessary.
In Chinese adults receiving high-dose statins for the secondary prevention of CVDs, adding ezetimibe is cost-effective compared to adding PCSK9 inhibitors and adding both drugs.
The age-related heterogeneity in major depressive disorder (MDD) has received significant attention. However, the neural mechanisms underlying such heterogeneity still need further investigation. This study aimed to explore the common and distinct functional brain abnormalities across different age groups of MDD patients from a large-sample, multicenter analysis.
The analyzed sample consisted of a total of 1238 individuals including 617 MDD patients (108 adolescents, 12–17 years old; 411 early-middle adults, 18–54 years old; and 98 late adults, > = 55 years old) and 621 demographically matched healthy controls (60 adolescents, 449 early-middle adults, and 112 late adults). MDD-related abnormalities in brain functional connectivity (FC) patterns were investigated in each age group separately and using the whole pooled sample, respectively.
We found shared FC reductions among the sensorimotor, visual, and auditory networks across all three age groups of MDD patients. Furthermore, adolescent patients uniquely exhibited increased sensorimotor-subcortical FC; early-middle adult patients uniquely exhibited decreased visual-subcortical FC; and late adult patients uniquely exhibited wide FC reductions within the subcortical, default-mode, cingulo-opercular, and attention networks. Analysis of covariance models using the whole pooled sample further revealed: (1) significant main effects of age group on FCs within most brain networks, suggesting that they are decreased with aging; and (2) a significant age group × MDD diagnosis interaction on FC within the default-mode network, which may be reflective of an accelerated aging-related decline in default-mode FCs.
To summarize, these findings may deepen our understanding of the age-related biological and clinical heterogeneity in MDD.
Compared with nitrogen and argon, helium is lighter and can better reduce the beam loss caused by angular scattering during beam transmission. The molecular dissociation cross-section in helium is high and stable at low energies, which makes helium the prevalent stripping gas in low-energy accelerator mass spectrometry (AMS). To study the stripping behavior of 14C ions in helium at low energies, the charge state distributions of carbon ion beams with −1, +1, +2, +3, and +4 charge states were measured at energies of 70–220 keV with a compact 14C-AMS at Guangxi Normal University (GXNU). The experimental data were used to analyze the stripping characteristics of C-He in the energy range of 70–220 keV, and new charge state yields and exchange cross-sections in C-He were obtained at energies of 70–220 keV.
Breast cancer is a high-risk disease with a high mortality rate among women. Chemotherapy plays an important role in the treatment of breast cancer. However, chemotherapy eventually results in tumours that are resistant to drugs. In recent years, many studies have revealed that the activation of Wnt/β-catenin signalling is crucial for the emergence and growth of breast tumours as well as the development of drug resistance. Additionally, drugs that target this pathway can reverse drug resistance in breast cancer therapy. Traditional Chinese medicine has the properties of multi-target and tenderness. Therefore, integrating traditional Chinese medicine and modern medicine into chemotherapy provides a new strategy for reversing the drug resistance of breast tumours. This paper mainly reviews the possible mechanism of Wnt/β-catenin in promoting the process of breast tumour drug resistance, and the progress of alkaloids extracted from traditional Chinese medicine in the targeting of this pathway in order to reverse the drug resistance of breast cancer.
Large gatherings of people on cruise ships and warships are often at high risk of COVID-19 infections. To assess the transmissibility of SARS-CoV-2 on warships and cruise ships and to quantify the effectiveness of the containment measures, the transmission coefficient (β), basic reproductive number (R0), and time to deploy containment measures were estimated by the Bayesian Susceptible-Exposed-Infected-Recovered model. A meta-analysis was conducted to predict vaccine protection with or without non-pharmaceutical interventions (NPIs). The analysis showed that implementing NPIs during voyages could reduce the transmission coefficients of SARS-CoV-2 by 50%. Two weeks into the voyage of a cruise that begins with 1 infected passenger out of a total of 3,711 passengers, we estimate there would be 45 (95% CI:25-71), 33 (95% CI:20-52), 18 (95% CI:11-26), 9 (95% CI:6-12), 4 (95% CI:3-5), and 2 (95% CI:2-2) final cases under 0%, 10%, 30%, 50%, 70%, and 90% vaccine protection, respectively, without NPIs. The timeliness of strict NPIs along with implementing strict quarantine and isolation measures is imperative to contain COVID-19 cases in cruise ships. The spread of COVID-19 on ships was predicted to be limited in scenarios corresponding to at least 70% protection from prior vaccination, across all passengers and crew.
A single-stage accelerator mass spectrometer (GXNU-AMS) developed for radiocarbon and tritium measurements was installed and commissioned at Guangxi Normal University in 2017. After several years of operational and methodological upgrades, its performance has been continuously improved and applied in multidisciplinary fields. Currently, the measurement sensitivity for radiocarbon and tritium is 14C/12C ∼ (3.14 ± 0.05) ×10–15 and 3H/1H ∼ (1.23 ± 0.17)×10–16, respectively, and the measurement accuracy is ∼0.6%, which can meet the measurement requirements in the nuclear, earth, environmental and life science fields. This study presents the performance characteristics of GXNU-AMS and several interesting application studies.
To assess the associations among several anthropometric measures, as well as BMI trajectories and colorectal cancer (CRC) risk in older women.
Prospective cohort study.
Forty clinical centres in the USA.
Totally, 79 034 postmenopausal women in the Women’s Health Initiative Observational Study.
During an average of 15·8 years of follow-up, 1514 CRC cases were ascertained. Five BMI trajectories over 18–50 years of age were identified using growth mixture model. Compared with women who had a normal BMI at age 18, women with obesity at age 18 had a higher risk of CRC (HR 1·58, 95 % CI 1·02, 2·44). Compared with women who kept relatively low normal body size during adulthood, women who progressed from normal to obesity (HR 1·29, 95 % CI 1·09, 1·53) and women who progressed from overweight to obesity (HR 1·37, 95 % CI 1·13, 1·68) had higher CRC risks. A weight gain > 15 kg from age 18 to 50 (HR 1·20, 95 % CI 1·04, 1·40) and baseline waist circumference > 88 cm (HR 1·33, 95 % CI 1·19, 1·49) were associated with higher CRC risks, compared with stable weight and waist circumference ≤ 88 cm, respectively.
Women who have a normal weight in early adult life and gain substantial weight later, as well as those who are persistently heavy over adulthood, demonstrated a higher risk of developing CRC. Our study highlights the importance of maintaining a healthy body weight over the life course for reducing the risk of developing CRC in women.
On February 24, 2021, a large explosion and fire occurred in an industrial estate in Singapore. Eight casualties with major burns were conveyed to the emergency department (ED) at Singapore General Hospital, the designated regional Burns Centre. This article details the events and recommendations arising from this multiple casualty incident.
An After-Action Review (AAR) was conducted to examine the prehospital notification process, casualty triage & tagging, medical management, manpower and resource allocation, and command-and-control structure.
All eight casualties were conveyed by the national Emergency Medical Services (EMS) and arrived within a 46-minute window. The first three suffered 90% full-thickness burns and inhalational injuries and were intubated. The remaining five suffered between 37% to 64% burns, with three requiring intubations as well.
Four major areas were identified for improvement:
Firstly, there was scant information from EMS regarding total casualty count. There was also inadequate knowledge of mass burns triage protocols in the ED. Thus, resources were heavily utilized for the first three casualties - all of whom were later deemed unsalvageable, given palliative care and demised.
Secondly, casualty identities were initially unknown. They were tagged with similar-looking ten-digit serial numbers, resulting in a near-miss event involving mislabelled blood tubes.
Thirdly, there was unfamiliarity with the incident response plan for a multiple casualty incident of this scale. This contributed to lack of situational oversight and inconsistent leadership direction from various stakeholders with resulting conflicting instructions.
Fourthly, routine trauma computed tomography pan-scans for all casualties caused delayed reporting by Radiology and created a bottleneck in casualty disposition.
A multi-disciplinary workgroup comprising Emergency, Trauma, Burns and Intensive Care departments outlined several recommendations based on the AAR findings. Drills were strongly recommended to resume following a hiatus due to COVID-19.
AARs help provide invaluable insights. Response plans should be refined together with relevant stakeholders.
The aim of the present study is to examine whether overweight or obese people in Taiwan have an inadequate intake of selected micronutrients. A population-based study was conducted using data from the Nutrition and Health Survey in Taiwan (NAHSIT) 2013–2016. We evaluated fourteen nutrient intakes using the 24 h dietary recall method. The dietary reference intake (DRI) adherence was estimated by the prevalence of participants whose intake was lower than the recommended dietary allowance (RDA) or adequate intakes (AIs) for selected micronutrients. Body mass index (BMI) ≥ 27 kg/m2 and waist circumference (WC), with men having WC ≥ 90 cm or women having WC ≥ 80 cm, were defined as obesity. A total of 3075 participants aged 19 years and above were included. After adjusting for confounders, we found that obese women have a lower DRI adherence of vitamin C (odds ratio (OR) 0⋅73, 95 % confidence interval (CI) 0⋅56, 0⋅95) and magnesium (OR 0⋅72, 95 % CI 0⋅54, 0⋅95), compared with normal-weight women. Obese men have a higher DRI adherence of vitamin B3 (OR 1⋅70, 95 % CI 1⋅29, 2⋅23), iron (OR 1⋅46, 95 % CI 1⋅06, 2⋅00) and zinc (OR 1⋅41, 95 % CI 1⋅07, 1⋅85), compared with normal-weight men. Similar findings were found using WC to define obesity. We conclude that obese women may have insufficient intakes of vitamin A, vitamin C and magnesium.
The resurgence and outbreaks of mumps occur frequently in many countries worldwide in recent years, even in countries with high vaccination coverage. In this study, a descriptive and spatiotemporal clustering analysis at the township level was conducted to explore the dynamic spatiotemporal aggregation and epidemiological characteristics of mumps in Wuhan. During 2005 and 2019, there were 40 685 cases reported in Wuhan, with an average annual morbidity of 28.11 per 100 000 populations. The morbidity showed a fluctuating tendency, and peaked in 2010 and 2018. Bimodal seasonality was found, with a large peak between May and July, and a mild peak from November to January in the following year. Male students aged 5–9-year-old were the main risk group of mumps infection. Significant global spatial auto-correlation was detected except in 2007, 2009 and 2015. The spatial and temporal scan statistics indicated that the hot-spots mainly located at the western and southern areas of Wuhan with variations almost every year. Our findings could assist the public health authorities to develop and improve targeted health strategies, and allocate health resources rationally.
There was no previous meta-analysis investigating the efficacy/tolerability of psychostimulants for symptoms of attention-deficit hyperactivity disorder (ADHD) in preschool children.
Databases including PubMed, the Cochrane Library, EMBASE, ScienceDirect, and ClinicalTrials.gov were searched from inception to March 2022 for randomized controlled trials (RCTs) on therapeutic efficacy of psychostimulants against ADHD symptoms in preschool children (age ≤6 years) compared with placebos. Primary outcomes were (a) changes in ADHD symptoms evaluated by validated rating scales from parents’/teacher’s observation, or (b) post-intervention improvements in neuropsychological performance. Secondary outcomes were risks of adverse events.
Meta-analysis of nine eligible trials including 544 preschool children (mean age=4.86 years, female=11.98%, median treatment duration=4.33 weeks) supported the efficacy of psychostimulants against global symptoms from observations of parents (Hedges’ g=0.6152, p<0.0001) and teachers (Hedges’ g=0.6563, p=0.0039). Efficacy of psychostimulants was also noted against symptoms of inattention and hyperactivity/impulsivity, especially the latter (i.e., main symptoms in preschool children). Moreover, male gender, older age, and longer treatment duration were associated with better efficacy. Regarding adverse events, only the risk of poor appetite was higher in the psychostimulant group (odds ratio [OR]=2.39). However, the qualities of evidence were low to very low, indicating potential discrepancy between the true and estimated effect.
Our results showed that psychostimulants might be beneficial for preschool children with ADHD, especially hyperactivity/impulsivity from teachers’ observation, with tolerable side effects. Nevertheless, the true magnitude of the effect needs to be confirmed with more research due to low to very low certainty of the evidence.
This study examines how maximum emotional intelligence (EI) members can contribute to the emergence of team-level organizational citizenship behaviors (OCB). Based on integrating a strategic core role and multilevel theory, we developed and tested a model in which the maximum EI score in teams results in intrateam trust and consequently impacts team OCB and examined whether the indirect effect of maximum EI on team OCB through intrateam trust would be moderated by EI diversity and trust divergence in teams. The results from 129 project teams showed that the relationship of maximum EI with team OCB is mediated by intrateam trust and this relationship is stronger for lower levels of EI diversity and trust divergence than for higher levels of diversity and divergence. The findings advance our understanding of the role of EI in team settings. Our research has important implications for organizations attempting to develop the applied value of EI.
The Palaeo-Mesozoic geodynamic evolution of the Tangjia–Sumdo accretionary complex belt, which separates the North and South Lhasa Terrane, remains controversial. Moreover, the lack of geological records restricts the understanding of the evolution of the Sumdo Palaeo-Tethys Ocean from the middle Permian until the middle Triassic. Here we present zircon U–Pb geochronology, whole-rock geochemistry and Sr–Nd–Hf isotopic compositions of the Yeqing gabbro. Zircon U–Pb geochronology yields ages from 254 ± 1 to 249 ± 1 Ma. In situ Hf isotopic analyses yield ϵHf(t) values of −0.2 to +6.3. These samples have high TiO2 (3.69 wt %) and P2O5 (0.78 wt %) contents, with typical patterns like ocean island basalt (OIB). Besides, they are classified as high-Nb basalts (HNBs) based on the high content of Nb (45.3–113.5 ppm). Whole-rock Sr–Nd isotopic compositions are similar to OIB, with initial 87Sr/86Sr of 0.7047–0.7054, 143Nd/144Nd of 0.512526–0.512647 and ϵNd(t) of 0.3–2.7. These signatures suggest that the Yeqing gabbro is mainly derived from low-degree melting of the garnet lherzolite mantle. Based on field observations of HNBs intruding into the continental margin and their geochemical characteristics, we infer that the Yeqing gabbro was generated in a subduction environment. Combined with the regional geology of the subduction environment and the evolution of oceanic islands in the Sumdo Palaeo-Tethys Ocean, we propose that the Yeqing gabbro may represent a product of the asthenosphere upwelling through a slab window produced by subduction of seismic ridge in the Sumdo Palaeo-Tethys Ocean, called plume – subduction-zone interaction, during the late Permian to early Triassic.
Everyone faces uncertainty on a daily basis. Two kinds of probability expressions, verbal and numerical, have been used to characterize the uncertainty that we face. Because our cognitive concept of living things differs from that of non-living things, and distinguishing cognitive concepts might have linguistic markers, we designed four studies to test whether people use different probability expressions when faced with animate or inanimate uncertainty. We found that verbal probability is the preferred way to express animate uncertainty, whereas numerical probability is the preferred way to express inanimate uncertainty. The “verbal-animate” and “numerical-inanimate” associations were robust enough to persist when tested with forced-choice response patterns regardless of the information (e.g., equally likely outcomes, frequencies, or personal beliefs) used to construct probabilities of events. When the response pattern was changed to free-responses, the associations were evident unless the subjects were asked to write their own probability predictions for vague uncertainty. Given that the world around us consists of both animate (i.e., living) and inanimate (i.e., non-living) things, “verbal-animate” and “numerical-inanimate” associations may play a major role in risk communication and may otherwise be useful for practitioners and consultants.