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Since the implementation of the Basel III Accord, expected shortfall (ES) has gained increasing attention from regulators as a complement to value-at-risk (VaR). The problem of elicitability for ES makes jointly modeling VaR and ES a popular method to study ES. In this article, we develop model averaging for joint VaR and ES regression models that selects the two weight vectors by minimizing a jackknife criterion. We show the large sample properties of the estimators under potential model misspecification with increasing dimension of parameters and the asymptotic optimality of the selected weights in the sense of minimizing the out-of-sample excess final prediction error. Simulation studies and three empirical analyses reveal good finite sample performance.
The double-cone ignition scheme is a promising novel ignition method, which is expected to greatly save the driver energy and enhance the robustness of the implosion process. In this paper, ablation of the inner surface of the cone by the hard X-ray from coronal Au plasma is studied via radiation hydrodynamics simulations. It is found that the X-ray ablation of the inner wall will form strong pre-plasma, which will significantly affect the implosion process and cause the Au plasma to mix with the fuel, leading to ignition failure. The radiation and pre-ablation intensities in the system are estimated, and the evolutions of areal density, ion temperature and the distribution of Au ions are analysed. In addition, the mixing of Au in CH at collision is quantified. Then, a scheme to reduce the X-ray pre-ablation by replacing the gold cone with a tungsten cone is proposed, showing that it is effective in reducing high-Z mixing and improving collision results.
This study demonstrates a kilowatt-level, spectrum-programmable, multi-wavelength fiber laser (MWFL) with wavelength, interval and intensity tunability. The central wavelength tuning range is 1060–1095 nm and the tunable number is controllable from 1 to 5. The wavelength interval can be tuned from 6 to 32 nm and the intensity of each channel can be adjusted independently. Maximum output power up to approximately 1100 W has been achieved by master oscillator power amplifier structures. We also investigate the wavelength evolution experimentally considering the difference of gain competition, which may give a primary reference for kW-level high-power MWFL spectral manipulation. To the best of our knowledge, this is the highest output power ever reported for a programmable MWFL. Benefiting from its high power and flexible spectral manipulability, the proposed MWFL has great potential in versatile applications such as nonlinear frequency conversion and spectroscopy.
Identification of the origins of maritime-traded porcelain, though key to unravelling ancient production and trade dynamics, remains challenging. The authors present a pioneering micro-provenance analysis of Dehua-style porcelain from the late-twelfth-century Nanhai I shipwreck, recovered from the South China Sea. By pinpointing the origins of porcelain subtypes, including those bearing ink inscriptions, this study provides greater nuance in understanding spatial patterns of production and the impact of buyer/seller choice in maritime trade. The findings further highlight the effectiveness of portable x-ray fluorescence as a high-precision provenancing analysis and offer insights into porcelain production timelines in south-east China.
Growing evidence indicates a link between diet and depression risk. We aimed to examine the association between an inflammatory diet index and depression utilising extensive data from UK biobank cohort. The energy-adjusted dietary inflammation index (E-DII) was calculated to quantify the potential of daily diet, with twenty-seven food parameters utilised. The E-DII scores were classified into two categories (low v. high) based on median value. To mitigate bias and ensure comparability of participant characteristics, propensity score matching was employed. To ascertain the robustness of these associations, sensitivity analyses were conducted. Subgroup analyses were performed to evaluate the consistency of these associations within different subpopulations. Totally, 152 853 participants entered the primary analyses with a mean age of 56·11 (sd 7·98) years. Employing both univariate and multivariate logistic regression models, adjustments were made for varying degrees of confounding factors (socio-demographics, lifestyle factors, common chronic medical conditions including type 2 diabetes and hypertension). Results consistently revealed a noteworthy positive correlation between E-DII and depression. In the context of propensity score matching, participants displaying higher E-DII scores exhibited an increased likelihood of experiencing incident depression (OR = 1·12, 95 % CI: 1·05, 1·19; P = 0·000316). Subgroup analysis results demonstrated variations in these associations across diverse subpopulations. The E-value for the point-estimate OR calculated from the propensity score matching dataset was 1·48. Excluding individuals diagnosed with type 2 diabetes or hypertension, the findings consistently aligned with the positive association in the primary analysis. These findings suggested that consumption of a diet with higher pro-inflammatory potential might associated with an increase of future depression risk.
This research communication screened and identified differentiated expressed genes in bovine mammary epithelial cells (BMECs) upon prolactin (PRL) stimulation. PRL of 5 μg/ml increased β-casein synthesis in BMECs with milk protein synthesis capacity. RNA sequencing (RNA-seq) was used to screen differentially expressed genes (DEGs). A total of 375 DEGs (165 up-regulated and 210 down-regulated) were identified between PRL-stimulated group and the control group. Gene ontology enrichment analysis showed that the up-regulated genes were primarily associated with cell functions, metabolic processes, and biological regulatory processes. Pathway enrichment analysis showed that the up-regulated genes were mainly enriched in JAK-STAT, Rap1, Ras and Notch signaling pathways, which are widely involved in cell proliferation, differentiation and milk component synthesis. This study provides an initial understanding of the changes in gene expression in BMECs with PRL-stimulation, as determined by RNA-seq transcriptomic analysis, thereby enhancing our knowledge of the molecular regulation of lactation metabolism.
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.
Gut microbiome changed dramatically during pregnancy and played important roles in metabolic status and reproductive endocrinology in mammals. However, investigating the functional microbiota and metabolites to improve the reproductive performance and understanding the host–microbiota interaction are still arduous tasks. This study aims to reveal the dominant strains and metabolites that improve the reproductive performance. We analyzed the fecal microbiota composition and metabolic status of higher yield Chinese pig breed Meishan (MS) sows and lower yield but widespread raised hybrid pig breed Landrace × Yorkshire (L × Y) sows on days 28 and 100 of gestation. Results showed that MS sows had higher litter sizes and steroid hormone level but lower short-chain fatty acid level in feces. Fecal metabolomic analysis revealed that MS sows showed a different metabolic status compared with L × Y sows both at early and late pregnancy, which enriched with phenylpropanoid biosynthesis, bile secretion, steroid hormone biosynthesis, and plant secondary metabolite biosynthesis. In addition, 16S rDNA and internal transcribed spacer sequencing indicated that MS sows showed different structures of microbiota community and exhibited an increased bacterial α-diversity but non-differential fungal α-diversity than L × Y sows. Moreover, we found that the litter sizes and bacteria including Sphaerochaeta, Solibacillus, Oscillospira, Escherichia–Shigella, Prevotellaceae_UCG-001, dgA-11_gut_group, and Bacteroides, as well as fungi including Penicillium, Fusarium, Microascus, Elutherascus, and Heydenia both have positive association to the significant metabolites at the early pregnancy. Our findings revealed significant correlation between reproductive performance and gut microbiome and provided microbial and metabolic perspective to improve litter sizes and steroid hormones of sows.
The Righi–Leduc heat flux generated by the self-generated magnetic field in the ablative Rayleigh–Taylor instability driven by a laser irradiating thin targets is studied through two-dimensional extended-magnetohydrodynamic simulations. The perturbation structure gets into a low magnetization state though the peak strength of the self-generated magnetic field could reach hundreds of teslas. The Righi–Leduc effect plays an essential impact both in the linear and nonlinear stages, and it deflects the total heat flux towards the spike base. Compared to the case without the self-generated magnetic field included, less heat flux is concentrated at the spike tip, finally mitigating the ablative stabilization and leading to an increase in the velocity of the spike tip. It is shown that the linear growth rate is increased by about 10% and the amplitude during the nonlinear stage is increased by even more than 10% due to the feedback of the magnetic field, respectively. Our results reveal the importance of Righi–Leduc heat flux to the growth of the instability and promote deep understanding of the instability evolution together with the self-generated magnetic field, especially during the acceleration stage in inertial confinement fusion.
This article presents relevant data on the usage of the sinograph jīng 椋 and revisits its origin and lexical form on the basis of textual examination, using primary sources from China, Korea and Japan. The authors conclude that jīng 椋, and its variants jīng, jīng 稤 and the miscopied form lǜe 掠, originated from its radical character jīng 京, meaning “warehouse, granary”, and that jīng 椋 was widely used in Koguryŏ, Paekche, Silla and Japan. Historical documents during the Koryŏ period also attest to the use of jīng 椋. The authors have reconstructed the lexical form of jīng 椋 as the disyllabic pre-Old Korean **kuL.raH in Paekche and **koL.raH in Silla, and the monosyllabic Old Korean *kolR as a Sillaic substratum that underwent the syllabic contraction and liquid change **-r- > *-l, that is **koL.raH > *kolR. The Western Old Japanese kun'yomi of jīng 椋, kura, is a loan from pre-Old Korean **kuL/koL.raH that took place before the eighth century.
Post-event rumination (PER) has been seen as a key element in the persistence of social anxiety (disorder). Studies on PER-targeted intervention, e.g., cognitive restructuring (CR), has, however, received little attention in adults, not yet in youth. In addition, previous research showed that, compared to interaction, participants reported higher levels of PER after speech task. The main aim of the present study was to investigate the effect of CR targeting PER among socially anxious (Chinese) adolescents and also to compare the intervention effect between speech and interaction situations. The present study recruited a sample of 73 high socially anxious adolescents aged 12–16 years and then randomly assigned them into speech (n = 37) or interaction (n = 36) group, without control group. PER and social anxiety (SA) were measured before and after CR. Analysis of Covariance (ANCOVA) results showed that adolescents’ PER and SA symptoms were significantly improved with intervention with moderate to high effect size. Furthermore, the decrease in PER could significantly predict the improvement of SA. However, the intervention effect showed no difference between groups. Although no control group was included, one-session CR still showed its potential to improve participants’ PER and SA. Limitations and future directions were discussed.
The development of high-brightness X-ray free electron lasers (XFELs), such as hard X-ray self-seeding free electron lasers and XFEL oscillators (XFELOs), brings a severe challenge to the crystal monochromator due to a strong non-uniform thermal load. The distortion caused by spatial temperature gradients can severely affect the optical performance of crystals. Therefore, this paper presents a model to estimate the performance of non-uniform thermally distorted crystals. The model not only takes into account thermal strain, slope error and incident angle deviation, but also considers temperature-dependent factors such as the Debye–Waller factor and electric susceptibility. Our investigation indicates that the Debye–Waller factor reduces the height and bandwidth of rocking curves, and the impact of the electric susceptibility is tiny. The proposed model can describe the distortion of the reflectivity and transmissivity curves of non-uniform thermally loaded crystals and can be applied in the design of crystal monochromators, crystal splitters, crystal compressors and XFELOs.
In this paper, we reduce the logarithmic Sarnak conjecture to the $\{0,1\}$-symbolic systems with polynomial mean complexity. By showing that the logarithmic Sarnak conjecture holds for any topologically dynamical system with sublinear complexity, we provide a variant of the $1$-Fourier uniformity conjecture, where the frequencies are restricted to any subset of $[0,1]$ with packing dimension less than one.
Benzodiazepine receptor agonists (BZRAs) are commonly used clinically and data on their hazardous use from large populations of psychiatric patients is limited.
Aims
To assess the current status of hazardous BZRA use and related factors in Chinese out-patient psychiatric settings.
Method
The study included out-patients with at least one BZRA prescription from five psychiatric settings in east, central and west China in 2018. Demographic and prescription information were extracted from the electronic prescription database. We defined the co-occurrence of overdose and long-term use as hazardous use, and patients whose recorded diagnoses did not meet any indications approved by the Chinese Food and Drug Administration as over-indication users. Additionally, 200 hazardous users were randomly selected for follow-up interview to confirm the actual situation.
Results
Among 720 054 out-patients, 164 450 (22.8%) had at least one BZRA prescription; 55.9% of patients were prescribed over-indication and 3% were defined as hazardous users. Multilevel multivariate regression analysis with hospital as a random effect showed that factors associated with hazardous use were older age (18–64 years: β = 0.018; 95% CI 0.013–0.023; >65 years: β = 0.015; 95% CI 0.010–0.021), male (β = 0.005, 95% CI 0.003–0.007), over-indication (β = 0.013, 95% CI 0.012–0.015), more out-patient visits (β = 0.006, 95% CI 0.006–0.006) and more visits to different doctors (β = 0.007, 95% CI 0.007–0.008); 98.5% of hazardous users (197/200) could not be contacted.
Conclusions
BZRAs are commonly used and there is a relatively large proportion of over-indication users among Chinese psychiatric out-patients. However, only a small proportion of hazardous users were detected. The study highlights how to use prescription data to support improvements in clinical practice.
When a charge neutral drop impacts on a flat solid substrate, a small air bubble is always trapped underneath due to the lubrication pressure coming from the viscous stress in the squeezed air film. Herein we find experimentally and numerically that the process of the air entrapment and the initial contact state of the drop with the substrate can be profoundly altered via an external electric field. In an electric field, the induced electric stresses at the bottom of the drop increase drastically right before the drop contacts the substrate, which acts against the lubrication pressure, resulting in reduced initial contact radius and air bubble size. When the external electric field reaches a critical value, the electrical stress accelerates the flow near the bottom of the drop and generates a conical tip quickly instead of a dimple, resulting in a centre contact and eliminating the air bubble entrapment. Based on the dipole mirror charge model, we find the dimensionless strength of critical electric field scales with the square root of capillary number based on the air viscosity. This scaling law of the critical electric field for eliminating the air bubble entrapment is verified experimentally and numerically. This work may offer a new way to mitigate defects caused by air bubble entrapment for inkjet printing and droplet-based additive manufacturing.
There is a lack of evidence related to the prevalence of mental health symptoms as well as their heterogeneities during the coronavirus disease 2019 (COVID-19) pandemic in Latin America, a large area spanning the equator. The current study aims to provide meta-analytical evidence on mental health symptoms during COVID-19 among frontline healthcare workers, general healthcare workers, the general population and university students in Latin America.
Methods
Bibliographical databases, such as PubMed, Embase, Web of Science, PsycINFO and medRxiv, were systematically searched to identify pertinent studies up to August 13, 2021. Two coders performed the screening using predefined eligibility criteria. Studies were assigned quality scores using the Mixed Methods Appraisal Tool. The double data extraction method was used to minimise data entry errors.
Results
A total of 62 studies with 196 950 participants in Latin America were identified. The pooled prevalence of anxiety, depression, distress and insomnia was 35%, 35%, 32% and 35%, respectively. There was a higher prevalence of mental health symptoms in South America compared to Central America (36% v. 28%, p < 0.001), in countries speaking Portuguese (40%) v. Spanish (30%). The pooled prevalence of mental health symptoms in the general population, general healthcare workers, frontline healthcare workers and students in Latin America was 37%, 34%, 33% and 45%, respectively.
Conclusions
The high yet heterogenous level of prevalence of mental health symptoms emphasises the need for appropriate identification of psychological interventions in Latin America.
Although immune checkpoint inhibitors (ICIs) have produced remarkable responses in non-small cell lung cancer (NSCLC) patients, receivers still have a relatively low response rate. Initial response assessment by conventional imaging and evaluation criteria is often unable to identify whether patients can achieve durable clinical benefit from ICIs. Overall, there are sparse effective biomarkers identified to screen NSCLC patients responding to this therapy. A lot of studies have reported that patients with specific gene mutations may benefit from or resist to immunotherapy. However, the single gene mutation may be not effective enough to predict the benefit from immunotherapy for patients. With the advancement in sequencing technology, further studies indicate that many mutations often co-occur and suggest a drastic transformation of tumour microenvironment phenotype. Moreover, co-mutation events have been reported to synergise to activate or suppress signalling pathways of anti-tumour immune response, which also indicates a potential target for combining intervention. Thus, the different mutation profile (especially co-mutation) of patients may be an important concern for predicting or promoting the efficacy of ICIs. However, there is a lack of comprehensive knowledge of this field until now. Therefore, in this study, we reviewed and elaborated the value of cancer mutation profile in predicting the efficacy of immunotherapy and analysed the underlying mechanisms, to provide an alternative way for screening dominant groups, and thereby, optimising individualised therapy for NSCLC patients.
The quantum defect (QD) is an important issue that demands prompt attention in high-power fiber lasers. A large QD may aggravate the thermal load in the laser, which would impact the frequency, amplitude noise and mode stability, and threaten the security of the high-power laser system. Here, we propose and demonstrate a cladding-pumped Raman fiber laser (RFL) with QD of less than 1%. Using the Raman gain of the boson peak in a phosphorus-doped fiber to enable the cladding pump, the QD is reduced to as low as 0.78% with a 23.7 W output power. To our knowledge, this is the lowest QD ever reported in a cladding-pumped RFL. Furthermore, the output power can be scaled to 47.7 W with a QD of 1.29%. This work not only offers a preliminary platform for the realization of high-power low-QD fiber lasers, but also proves the great potential of low-QD fiber lasers in power scaling.