Post-acceleration of protons in helical coil targets driven by intense, ultrashort laser pulses can enhance ion energy by utilizing the transient current from the targets’ self-discharge. The acceleration length of protons can exceed a few millimeters, and the acceleration gradient is of the order of GeV/m. How to ensure the synchronization between the accelerating electric field and the protons is a crucial problem for efficient post-acceleration. In this paper, we study how the electric field mismatch induced by current dispersion affects the synchronous acceleration of protons. We propose a scheme using a two-stage helical coil to control the current dispersion. With optimized parameters, the energy gain of protons is increased by four times. Proton energy is expected to reach 45 MeV using a hundreds-of-terawatts laser, or more than 100 MeV using a petawatt laser, by controlling the current dispersion.

Trematodes of the genus Ogmocotyle are intestinal flukes that can infect a variety of definitive hosts, resulting in significant economic losses worldwide. However, there are few studies on molecular data of these trematodes. In this study, the mitochondrial (mt) genome of Ogmocotyle ailuri isolated from red panda (Ailurus fulgens) was determined and compared with those from Pronocephalata to investigate the mt genome content, genetic distance, gene rearrangements and phylogeny. The complete mt genome of O. ailuri is a typical closed circular molecule of 14 642 base pairs, comprising 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. All genes are transcribed in the same direction. In addition, 23 intergenic spacers and 2 locations with gene overlaps were determined. Sequence identities and sliding window analysis indicated that cox1 is the most conserved gene among 12 PCGs in O. ailuri mt genome. The sequenced mt genomes of the 48 Plagiorchiida trematodes showed 5 types of gene arrangement based on all mt genome genes, with the gene arrangement of O. ailuri being type I. Phylogenetic analysis using concatenated amino acid sequences of 12 PCGs revealed that O. ailuri was closer to Ogmocotyle sikae than to Notocotylus intestinalis. These data enhance the Ogmocotyle mt genome database and provide molecular resources for further studies of Pronocephalata taxonomy, population genetics and systematics.

For a quadratic Markov branching process (QMBP), we show that the decay parameter is equal to the first eigenvalue of a Sturm–Liouville operator associated with the partial differential equation that the generating function of the transition probability satisfies. The proof is based on the spectral properties of the Sturm–Liouville operator. Both the upper and lower bounds of the decay parameter are given explicitly by means of a version of Hardy’s inequality. Two examples are provided to illustrate our results. The important quantity, the Hardy index, which is closely linked to the decay parameter of the QMBP, is deeply investigated and estimated.

The Qieganbulake deposit associated with a mafic–ultramafic–carbonatite complex in the Kuluketage block is not only the world’s second-largest vermiculite deposit, but also a medium-size carbonatite-related phosphate deposit. Field observations, radiometric dating results and Sr–Nd–Hf isotopes reveal that the parental magmas of the carbonatite and mafic–ultramafic rocks are cogenetic and formed synchronously at c. 810 Ma. Geochemical characteristics and Sr–Nd–Hf–S isotopes ((87Sr/86Sr)i = 0.70581–0.70710; ϵNd(t) = −0.20 to −11.80; ϵHf(t) = −7.5 to −10.3; δ34S = +0.7 ‰ to +3.0 ‰ (some sulfides with high δ34S values (+3.2 to +6.6) were formed by late hydrothermal sulfur)), in combination with mineral compositions and previous research, strongly indicate that the Qieganbulake mafic–ultramafic–carbonatite complex formed via extensive crystal fractionation/cumulation and liquid immiscibility of a carbonated tholeiitic magma, possibly derived from partial melting of an enriched subcontinental lithospheric mantle previously modified by slab-released fluids and sediment input in a continental rift setting. The coupled enriched Sr–Nd isotopic signatures, in combination with previous research, suggest that the enriched subcontinental lithospheric mantle could have been metasomatized by asthenospheric mantle melts to different degrees. The Qieganbulake carbonatite-related phosphate ores were the products of normal fractional crystallization/cumulation of P–Fe3+ complex enriched carbonatite magma in high oxygen fugacity conditions, which was generated by liquid immiscibility of CO2–Fe–Ti–P-rich residual magma undergoing high differentiation.

In 2016, an outbreak of paratyphoid fever occurred in 40 cases at Qingyang town, in China. A case-control study was carried out to determine the source of this outbreak. Case-control study was conducted to identify the risk factors of this outbreak. The cases were identified as patients with isolation of S. Paratyphi, controls were confirmed cases’ healthy classmates, colleagues or neighbors and matched by age (±5 y) and gender. Pulsed-field gel electrophoresis was performed to source tracking. Totally, 40 cases were reported: 24 cases were students, and 20 (20/24) of them were Qingyang High School students. For the case-control study, consuming Chinese egg pancakes was detected as a risk factor (OR1:1 = 5.000; 95% CI: 1.710-14.640), and hand-washing before meals was protective behavior compared with seldom hand-washing (OR1:1 = 23.256; 95% CI: 2.451-200.000). S. Paratyphi was cultured from a well water sample used for washing contents of the pancakes. Isolates from well water and paratyphoid cases showed the same PFGE patterns. Contaminated well water and Chinese egg pancakes were likely source and vehicle of this outbreak. Health education, especially handwashing, and food safety supervision should be promoted particularly in schools.

The low maturation rate of oocytes is an important reason for female infertility and failure of assisted pregnancy. The germinal vesicle breakdown (GVBD) is a landmark event of oocyte maturation. In our previous studies, we found that zona pellucida 3 (ZP3) was strongly concentrated in the nuclear region of germinal vesicle (GV) oocytes and interacted with aryl hydrocarbon receptor-interacting protein-like 1 (AIPL1) and lamin A to promote GVBD. In the current study, we found that lamin A is mainly concentrated in the nuclear membrane. When ZP3 is knocked down, lamin A will be partially transferred to the nucleus of oocytes. The prelamin A is increased in both the nuclear membrane and nucleus, while phosphorylated lamin A (p-lamin A) is significantly reduced. AIPL1 was also proved to accumulate in the GV region of oocytes, and ZP3 deletion can significantly inhibit the aggregation of AIPL1 in the nuclear region. Similar to ZP3 knockdown, the absence of AIPL1 resulted in a decrease in the occurrence of GVBD, an increase in the amount of prelamin A, and a significant decrease in p-lamin A in oocytes developed in vitro. Finally, we propose the hypothesis that ZP3 can stabilize farnesylated prelamin A on the nuclear membrane of AIPL1, and promote its further processing into mature lamin A, therefore promoting the occurrence of GVBD. This study may be an important supplement for the mechanism of oocyte meiotic resumption and provide new diagnostic targets and treatment clues for infertility patients with oocyte maturation disorder.

In China, celebrities can dominate public discourse and shape popular culture, but they are under the state's close gaze. Recent studies have revealed how the state disciplines and co-opts celebrities to promote patriotism, foster traditional values and spread political propaganda. However, how do celebrities adapt to the changing political environment? Focusing on political signalling on the social media platform Sina Weibo, we analyse a novel dataset and find that the vast majority of top celebrities repost from official accounts of government agencies and state media outlets, though there are variations. Younger celebrities with more followers tend to repost from official accounts more often. Celebrities from Taiwan tend to repost less than those from the mainland and Hong Kong, despite being subject to the same rules. However, the frequent political signalling by the most influential celebrities among younger generations suggests that the state has co-opted celebrity influence on social media to broadly promote its political objectives.

The identification of herbicide tolerance is essential for effective chemical weed control. According to whole-plant dose–response assays, none of 29 pond lovegrass [Eragrostis japonica (Thunb.) Trin.] populations were sensitive to penoxsulam. The effective dose values of penoxsulam causing 50% inhibition of fresh weight (GR50: 105.14 to 148.78 g ai ha−1) in E. japonica populations were much higher than the label rate of penoxsulam (15 to 30 g ai ha−1) in the field. This confirmed that E. japonica was tolerant to penoxsulam. Eragrostis japonica populations showed 52.83- to 74.76-fold higher tolerance to penoxsulam than susceptible barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.]. The mechanisms of tolerance to penoxsulam in E. japonica were also identified. In vitro activity assays revealed that the penoxsulam concentration required to inhibit 50% of the acetolactate synthase (ALS) activity (IC50) was 12.27-fold higher in E. japonica than in E. crus-galli. However, differences in the ALS gene, previously found to endow target-site resistance in weeds, were not detected in the sequences obtained. Additionally, the expression level of genes encoding ALS in E. japonica was approximately 2-fold higher than in E. crus-galli after penoxsulam treatment. Furthermore, penoxsulam tolerance can be significantly reversed by three cytochrome P450 monooxygenase (CytP450) inhibitors (1-aminobenzotriazole, piperonyl butoxide, and malathion), and the activity of NADPH-dependent cytochrome P450 reductase toward penoxsulam in E. japonica increased significantly (approximately 7-fold higher) compared with that of treated E. crus-galli. Taken together, these results indicate that lower ALS sensitivity, relatively higher ALS expression levels, and stronger metabolism of CytP450s combined to bring about penoxsulam tolerance in E. japonica.

Biped robots with dynamic motion control have shown strong robustness in complex environments. However, many motion planning methods rely on models, which have difficulty dynamically modifying the walking cycle, height, and other gait parameters to cope with environmental changes. In this study, a heuristic model-free gait template planning method with dynamic motion control is proposed. The gait trajectory can be generated by inputting the desired speed, walking cycle, and support height without a model. Then, the stable walking of the biped robot can be realized by foothold adjustment and whole-body dynamics model control. The gait template can be changed in real time to achieve gait flexibility of the biped robot. Finally, the effectiveness of the method is verified by simulations and experiments of the biped robot BHR-B2. The research presented here helps improve the gait transition ability of biped robots in dynamic locomotion.

Sleep is an integral part of individuals' health and wellbeing. Despite evidence showing that social stressors are important contributors to older adults' sleep problems, how the accumulative stressful life events (SLEs) and ageing attitudes independently and jointly affect sleep quality among older adults in developing countries remains unclear. This study examined the effects of SLEs on subjectively rated sleep quality among older adults in China, and explored the potential mediating and moderating roles of positive and negative ageing attitudes on the above association. Using data from the 2014 China Longitudinal Ageing Social Survey, we had complete data for 7,780 older adults aged 60 and older. We employed logistic regression models and the Karlson–Holm–Breen decomposition method. Our findings indicated that SLEs significantly increased the risk of poor sleep quality, especially for those who had experienced two or more SLEs during the past year. Positive ageing attitudes were associated with lower odds of poor sleep quality, whereas negative ageing attitudes were related to higher odds of poor sleep quality. Moreover, the mediation analyses suggested that SLEs were associated with poor sleep quality via negative ageing attitudes. The moderating effects further documented that higher levels of positive ageing attitudes can significantly attenuate the deleterious impact of SLEs on sleep quality. The findings highlight the significance of SLEs for older adults' sleep quality and shed light on the importance of ageing attitudes to improve older adults' sleep in China as well as other low- and middle-income countries, where the social safety nets are still underdeveloped.

Determining an effective approach to replacing chemical fertilizer with organic fertilizer is a difficult challenge for the Chinese government. This paper constructs a dynamic analysis framework with broader application than previous statistical and case studies by theoretically deriving the impact of farmers' participation in contract farming on their organic fertilizer application behavior. The framework analyzes farmers' intertemporal organic fertilizer application behavior under the two scenarios of participation and nonparticipation in contract farming. Participation in contract farming positively impacts organic fertilizer application behavior in both the short and long terms. Survey data from 473 vegetable farmers in Shandong province of China were used to conduct an empirical analysis, and the endogenous switching probit model was used to solve the endogeneity problem of farmers' participation in contract farming. The empirical analysis supports the above results: farmers' participation in contract farming increases their probability of applying organic fertilizer by 50.7%. Robustness tests conducted using the recursive bivariate probit model and replacing the dependent variable (the intensity with which farmers replace chemical fertilizer with organic fertilizer) confirm the research results. Further heterogeneity analysis shows that farmers' participation in contract farming has a more obvious promoting effect on organic fertilizer application behavior in the older group, the group with an education level of primary school or below and the small-scale farming group. Therefore, the government should promote participation in contract farming, especially among elderly, low-education and small-scale farmers, to improve the adoption level of organic fertilizer in China.

Hyperhomocysteinaemia (HHcy) is associated with all-cause mortality in some disease states. However, the correlation between HHcy and the risk of mortality in the general population has rarely been researched. We aimed to evaluate the association between HHcy and all-cause and cause-specific mortality among adults in the USA. This study analysed data from the National Health and Nutrition Examination Survey database (1999–2002 survey cycle). A multivariable Cox regression model was built to evaluate the correlation between HHcy and all-cause and cause-specific mortality. Smooth curve fitting was used to analyse their dose-dependent relationship. A total of 8442 adults aged 18–70 years were included in this study. After a median follow-up period of 14·7 years, 1007 (11·9 %) deaths occurred including 197 CVD-related deaths, 255 cancer-related deaths and fifty-eight respiratory disease deaths. The participants with HHcy had a 93 % increased risk of all-cause mortality (hazard ratio (HR) 1·93; 95 % CI (1·48, 2·51)), 160 % increased risk of CVD mortality (HR 2·60; 95 % CI (1·52, 4·45)) and 82 % increased risk of cancer mortality (HR 1·82; 95 % CI (1·03, 3·21)) compared with those without HHcy. For unmeasured confounding, E-value analysis proved to be robust. In conclusion, HHcy was associated with high risk of all-cause and cause-specific (CVD, cancer) mortality among adults aged below 70 years.