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In the present study, we investigate the modulation effects of particles on compressible turbulent boundary layers at a Mach number of 6, employing high-fidelity direct numerical simulations based on the Eulerian–Lagrangian point-particle approach. Our findings reveal that the mean and fluctuating velocities in particle-laden flows exhibit similarities to incompressible flows under compressibility transformations and semi-local viscous scaling. With increasing particle mass loading, the reduction in Reynolds shear stress and the increase in particle feedback force constitute competing effects, leading to a non-monotonic variation in skin friction, particularly in turbulence over cold walls. Furthermore, dilatational motions near the wall, manifested as travelling-wave structures, persist under the influence of particles. However, these structures are significantly weakened due to the suppression of solenoidal bursting events and the negative work exerted by the particle feedback force. These findings align with the insight of Yu et al. (J. Fluid. Mech., vol. 984, 2024, A44), who demonstrated that dilatational motions are generated by the vortices associated with intense bursting events, rather than acting as evolving perturbations beneath velocity streaks. The attenuation of travelling-wave structures at higher particle mass loadings also contributes to the reduction in the intensities of wall shear stress and heat flux fluctuations, as well as the probability of extreme events. These results highlight the potential of particle-laden flows to mitigate aerodynamic forces and thermal loads in high-speed vehicles.
Firefighters are frequently exposed to traumatic events and stressful environments and are at particularly high risk of depressive symptoms.
Aims:
The present study aimed to examine the impact of a combined internet-delivered cognitive behavioral therapy (iCBT) and attention bias modification (ABM) intervention to reduce depressive symptoms in firefighters.
Method:
The study was a randomized controlled trial carried out in Kunming, China, and involved the recruitment of 138 active firefighters as participants. The intervention lasted for an 8-week duration, during which participants participated in ABM exercises on alternating days and concurrently underwent eight modules of iCBT courses delivered through a smartphone application. Baseline and post-intervention assessments were conducted to evaluate the effects of the intervention.
Results and Discussion:
Results indicated that the combined iCBT and ABM intervention was significantly effective in reducing symptoms of depression compared with the no intervention control group (U=1644, p<0.001, Wilcoxon r=0.280). No significant change was observed in attention bias post-intervention (U=2460, p=0.737, Wilcoxon r=0.039), while a significant increase was observed in attention-bias variability (U=3172, p<0.001, Wilcoxon r=–0.287). This study provides evidence for the effectiveness of the combined iCBT and ABM intervention in reducing depressive symptoms among firefighters. This study provides conceptual support and preliminary evidence for the effectiveness of the combined iCBT and ABM intervention in reducing depressive symptoms among firefighters.
Caryocaridids are a unique representative of pelagic arthropods from the Ordovician period. They are typically found as flattened carapaces in mudstones and shales. This study reports on a species of caryocaridids, Soomicaris cedarbergensis, discovered in the Lower Ordovician of northwestern Xinjiang, NW China. The species shows the rare enrolled carapaces with a preserved cuticular ultrastructure. These specimens of caryocaridids from Xinjiang are the first reported in the Yili Block, and provide the substantial evidence that the paleogeographic distribution of caryocaridid phyllocarids could extend to the Central Asian Orogenic Belt. This species existed from the late Tremadocian until the end of the Ordovician (Hirnantian), making it the longest-ranging known species of caryocaridids. The carapace cuticle of S. cedarbergensis is composed of carbonate-fluorapatite and can be divided into three mineralized lamellae: outer, middle, and inner. The outer and inner lamellae each consist of three layers that correspond to the epicuticle, exocuticle, and endocuticle of extant crustacean carapaces. Moreover, the polygonal reticulation structure of the carapace in archaeostracans appears to be similar in shape and size to the hemolymph sinuses of leptostracans. This unique ultrastructure of the carapace cuticle in caryocaridids is believed to be better suited for a pelagic lifestyle.
The discovery that blazars dominate the extra-galactic $\gamma$-ray sky is a triumph in the Fermi era. However, the exact location of $\gamma$-ray emission region still remains in debate. Low-synchrotron-peaked blazars (LSPs) are estimated to produce high-energy radiation through the external Compton process, thus their emission regions are closely related to the external photon fields. We employed the seed factor approach proposed by Georganopoulos et al. It directly matches the observed seed factor of each LSP with the characteristic seed factors of external photon fields to locate the $\gamma$-ray emission region. A sample of 1 138 LSPs with peak frequencies and peak luminosities was adopted to plot a histogram distribution of observed seed factors. We also collected some spectral energy distributions (SEDs) of historical flare states to investigate the variation of $\gamma$-ray emission region. Those SEDs were fitted by both quadratic and cubic functions using the Markov-chain Monte Carlo method. Furthermore, we derived some physical parameters of blazars and compared them with the constraint of internal $\gamma\gamma$-absorption. We find that dusty torus dominates the soft photon fields of LSPs and most $\gamma$-ray emission regions of LSPs are located at 1–10 pc. The soft photon fields could also transition from dusty torus to broad line region and cosmic microwave background in different flare states. Our results suggest that the cubic function is better than the quadratic function to fit the SEDs.
Motoric cognitive risk syndrome (MCR), which is defined as a pre-dementia syndrome characterized by subjective cognitive complaints and slow gait in older individuals free of dementia and mobility disability, has been associated with increased risks of dementia, functional dependence, and mortality. The aims of this study were to describe the prevalence and distribution of MCR and to explore the clinical profiles associated with MCR in rural-dwelling older adults.
Methods:
The population-based cross-sectional study included 5,021 dementia- and disability-free participants (age ≥60 years; 56.48% women) in the baseline assessments (March-September 2018) of the Multimodal Interventions to delay Dementia and disability in rural China (MIND-China). The MCR syndrome was diagnosed when the participants had subjective memory complaints and gait speed ≥1 standard deviation (SD) below the age- (<75 and ≥75 years) and sex-specific means. We estimated the age- and sex-specific prevalence of MCR. We used logistic regression models to examine lifestyle and clinical factors associated with MCR while controlling for age, sex, and education.
Results:
The overall prevalence of MCR syndrome was 13.58%, with the prevalence being 11.53% in males and 15.16% in females (P<0.001). The prevalence of MCR was increased with age, from 10.43% in people aged 60-69 years and 15.97% in those aged 70-79 years to 21.71% among those aged ≥80 years. The demographic-adjusted odds ratio (95% confidence interval) of MCR was 1.30 (1.08-1.57) for being overweight (body mass index 24-27.9 vs. <24 kg/m2), 1.65 (1.32-2.05) for having obesity (≥28 kg/m2), 1.74 (1.41-2.15) for diabetes, 1.44 (1.20-1.73) for dyslipidemia, 1.59 (1.32-1.91) for having coronary heart disease, 2.17 (1.78-2.65) for having stroke history, 1.52 (1.24-1.86) for having osteoarthritis, and 3.40 (2.70-4.28) for having depressive symptoms. Ever (vs. never) smoking and alcohol consumption were related to odds ratio of 0.65 (0.48-0.86) and 0.71 (0.55-0.91), respectively, for MCR syndrome.
Conclusion:
The MCR syndrome affects nearly 1 in 7 Chinese rural older adults, and the MCR prevalence appears to be higher in women than in men. Cardiometabolic risk factors (e.g., overweight/obesity, diabetes, and dyslipidemia), osteoarthritis, coronary heart disease, stroke, and depressive symptoms were associated with increased likelihoods of the MCR syndrome.
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.
Methods
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.
Results
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.
Conclusion
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.
Much ink has been splashed on the ideological, conceptual, and practical challenges that China’s state capitalism has posed to global trade rules. There is a growing perception that the current international trade rules are neither conceptually coherent nor practically effective in tackling China’s state capitalism. This perception has not only led to the emergence of new trade rules in regional trade agreements, but also culminated in the US-China trade war, only further aggravated by the Covid-19 pandemic. This Article contributes to the debate of what trade rules may be needed to counteract China’s state capitalism by unpacking the black box of China’s state capitalism. Based on an analysis of the nature of China’s state capitalism, this Article provides a preliminary evaluation of current trade rules taken to counteract China’s state capitalism, in particular the new rules in the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, and explain why they are unlikely to be successful.
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.
Considering the influence of body’s growth and development on thyroid volume (TVOL), whether five existed corrected methods could be applied to correct TVOL remains unclear, in terms of Chinese children’s increased growth and development trends. This study aimed to compare the applicability of five correction methods: Body Surface Area corrected Volume (BSAV), Body Mass Indicator corrected Volume (BMIV), Weight and Height corrected Volume Indicator (WHVI), Height corrected Volume Indicator 1 (HVI1) and Height corrected Volume Indicator 2 (HVI2) and to establish the reference values for correction methods. The data of Iodine Nutrition and Thyroid Function Survey were used to analyse the differences in TVOL between normal and abnormal thyroid function children. Data of National Iodine Deficiency Disorders Survey were used to compare five correction methods and to establish their reference values. The median urinary iodine concentrations of children surveyed were 256·1 μg/l in 2009 and 192·6 μg/l in 2019. No significant difference was found in TVOL and thyroid goitre rate between children with normal and abnormal thyroid function. In the determination of goitre, HVI1, HVI2, BSAV and BMIV all showed high agreement with TVOL, while the area under the receiver operating characteristic curve (AUC) of WHVI was relatively low for children aged 8 (AUC = 0·8993) and 9 (AUC = 0·8866) years. Most differences of TVOL between light and heavy weight, short and tall height children can be eliminated by BSAV. BSAV was the best corrected method in this research. Reference values were established for corrected TVOL in Chinese children aged 8–10 years by sex.
Excessive iodine can lead to goiters. However, the relationship between the water iodine concentration (WIC) and goiter rate (GR) is unclear. This study aims to explore the factors that influence children’s GR in areas with high WIC and analyse the threshold value of the GR increase associated with the WIC. According to the monitoring of the areas with high WIC in China in 2018–2020, a total of 54 050 children in eight high water iodine provinces were chosen. Drinking water, urine and edible salt samples of children were collected. The thyroid volume (Tvol) was measured. A generalised additive model (GAM) was used to analyse the relationship between the WIC and GR in children. Among the 54 050 children in areas with high WIC, the overall GR was 3·34 %, the median of water iodine concentration was 127·0 µg/l, the median of urinary iodine concentration was 318 µg/l and the non-iodised salt coverage rate (NISCR) was 63·51 %. According to the GAM analysis results, water iodine and urinary iodine are factors that influence the Tvol and GR, while the NISCR affects only the GR. When the WIC was more than 420 µg/l or the urinary iodine concentration was more than 800 µg/l, the GR increased rapidly. When the NISCR reached more than 85 %, the GR was the lowest. Thus, in areas with high WIC, WIC more than 420 µg/l may increase the risk of goiter, and the NISCR should be increased to over 85 % to avoid goiters in children.
The policy of Universal Salt Iodisation (USI) could reduce population’s thyroid volume (TVOL) in iodine deficiency areas. Conversely, the improved growth and developmental status of children might increase the TVOL accordingly. Whether the decreased TVOL by USI conceals the increase effect of height and weight on TVOL is unclear. The aim of this study was to analyse the association between height, weight, iodine supplementation and TVOL. Five national Iodine Deficiency Disorder surveys were matched into four pairs according to the purpose of analysis. County-level data of both detected by paired surveys were incorporated; 1:1 random pairing method was used to match counties or individuals. The difference of TVOL between different height, weight, different iodine supplementation measures groups and the association between TVOL and them were studied. The mean height and weight of children aged 8–10 years increased from 129·9 cm and 26·9 kg in 2002 to 136·2 cm and 32·1 kg in 2019, while the median TVOL decreased from 3·10 ml to 2·61 ml. Iodine supplementation measures can affect TVOL; after excluding iodine effects, the median TVOL was increased with the height and weight. On the other side, after excluding the influence of height and weight, the median TVOL remained decreased. Only age, weight and salt iodine were significantly associated with TVOL in multiple linear models. Development of height and weight in children is the evidence of improved nutrition. The decreased TVOL caused by iodised salt measures conceals the increase effect of height and weight on TVOL. Age, weight and salt iodine affect TVOL significantly.
To determine if specific dietary patterns are associated with breast cancer (BC) risk in Chinese women.
Design:
Latent class analysis (LCA) was performed to identify generic dietary patterns based on daily food-frequency data.
Setting:
The Chinese Wuxi Exposure and Breast Cancer Study (2013–2014).
Participants:
A population-based case–control study (695 cases, 804 controls).
Results:
Four dietary patterns were identified, Prudent, Chinese traditional, Western and Picky; the proportion in the controls and cases was 0·30/0·32/0·16/0·23 and 0·29/0·26/0·11/0·33, respectively. Women in Picky class were characterised by higher extreme probabilities of non-consumption of specific foods, the highest probabilities of consumption of pickled foods and the lowest probabilities of consumption of cereals, soya foods and nuts. Compared with Prudent class, Picky class was associated with a higher risk (OR = 1·42, 95 % CI 1·06, 1·90), while the relevant association was only in post- (OR = 1·44, 95 % CI 1·01, 2·05) but not in premenopausal women. The Western class characterised by high-protein, high-fat and high-sugar foods, and the Chinese traditional class characterised by typical consumption of soya foods and white meat over red meat, both of them showed no difference in BC risk compared with Prudent class did.
Conclusions:
LCA captures the heterogeneity of individuals embedded in the population and could be a useful approach in the study of dietary pattern and disease. Our results indicated that the Picky class might have a positive association with the risk of BC.
Health system reform is considered a tough issue worldwide. Great efforts have been made toward health system building and strengthening. However, it is still unclear which health system is appropriate for different countries. This study aimed to systematically compare the characteristics of the establishment periods between eighty-eight counties of National Health Service (NHS) and Social Health Insurance (SHI).
Methods:
Forty-eight NHS countries and forty SHI countries with data availability were selected. The establishment years of current health systems and other eighteen indicators in economics, society, population and health during establishment periods were collected. Comparison between NHS and SHI was conducted by descriptive analysis of every indicator.
Results:
Most NHS countries were established during the cold war, while SHI had been set up since the cold war ended. The median of gross domestic product (GDP) per capita, urbanization rate and aging rate of SHI were USD 1535 in current dollars, 58.2 percent and 9.8 percent, respectively; compared with USD 1387, 41.2 percent and 4.7 percent, respectively of NHS. NHS countries had a smaller total population, lower mortality rate and elderly dependency ratio, while the birth rate and children's dependency ratio were higher. SHI countries showed a higher life expectancy and lower mortality rate in infants and children. NHS countries spent less in total health expenditure and a lower proportion of GDP. The median health expenditure per capita of SHI and NHS were USD 188 and USD 131 in current dollars, respectively. There was little difference among maternal mortality rates, and public and private health expenditure proportions.
Conclusions:
NHS and SHI countries had different characteristics during the health system establishment periods. NHS was established earlier than SHI overall, so that SHI revealed higher levels in economic and social development. Health outcomes of NHS countries were slightly lower than SHI ones, while health expenditure was more in SHI countries. Specific social, economic, demographic and health conditions should be considered when countries are building their own health systems.
Following the proliferation of private standards in the global supply chain trade, it has become clear that these can have adverse effects on international commerce and world welfare in the same way that government-imposed mandatory regulations do. However, the scope of the obligation of WTO Members in relation to the regulation of private standards remains vague and open to divergent interpretations under WTO law. This article starts from the premise that the debate should move beyond the search for a reasonable interpretation of relevant WTO disciplines and instead begin to consider normative questions concerning the legitimacy and accountability of transnational private regulation in global governance and the potential role of the WTO in regulating such private authority. The article explores what justifies the role of the WTO, a multilateral intergovernmental organization, in regulating transnational private standards and how a regulatory mechanism might be designed and implemented in practice.
High-quality carbon nanotubes (CNTs) and graphene synthesized by chemical vapor deposition (CVD) have unique one- and two-dimensional structures made up of sp2-hybridized carbon atoms and excellent physical and chemical properties. They have shown potential for use in electronics, optoelectronics, energy-storage devices, composites, and sensors. In this article, we review important milestones in these uses of CNTs and graphene produced by CVD, with special emphasis on the latest advances and remaining challenges. The key characteristics and advantages of CNTs and graphene synthesized by CVD for different applications are compared, and future trends in the use of these nanocarbons are discussed.
Toxoplasma gondii is an obligate intracellular parasite of phylum Apicomplexa. To facilitate high-efficiency invasion of host cells, T. gondii secretes various proteins related to the moving junction (MJ) complex from rhoptries and micronemes into the interface between the parasite and host. AMA1/RON2/4/5/8 is an important MJ complex, but its mechanism of assembly remains unclear. In this study, we used the CRISPR-Cas9 system to generate a derivative of T. gondii strain RH with a null mutation in TgRON4, thought to be an essential MJ component. Deficiency of TgRON4 moderately decreased invasion ability relative to that of the wild-type parasite. In addition, expression of the endogenous N-terminal fragment of RON5 decreased in the mutant. Together, the results improve our understanding of the assembly mechanism of the MJ complex of T. gondii and raise the possibility of developing new therapeutic drugs that target this complex.
One important issue arising from EC–Seal Products is what constitutes a technical regulation in the TBT Agreement. This article argues that the Appellate Body's analytical approach to this issue has led to an arbitrary conclusion in EC–Seal Products. The article further examines to what extent PPMs, especially Non–product–related PPMs, are covered by the TBT Agreement. The article concludes that an important question to be answered is what special characteristics of a technical regulation distinguish it from other regulations and make it subject to more detailed obligations in the TBT Agreement.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
The national treatment (NT) obligation embodied in Article III:4 of the GATT 1994 has been long marked by legal indeterminacy. Recently, the WTO Appellate Body has shed some fresh light on how the NT obligation should be interpreted in EC–Seal Products. The Appellate Body's report on EC–Seal Products and other recent developments in WTO case law have fundamentally reshaped our collective understanding of the NT obligation. The purpose of this article is to take stock of what we have known about the NT obligation in GATT Article III:4 after EC–Seal Products, as well as identifying some lingering uncertainties. This paper argues that the boundary of the NT obligation in GATT Article III:4 will be largely determined by how the Appellate Body deals with three big issues identified in this article in future disputes.