The Weibel instability and the induced magnetic field are of great importance for both astrophysics and inertial confinement fusion. Because of the stochasticity of this magnetic field, its main wavelength and mean strength, which are key characteristics of the Weibel instability, are still unobtainable experimentally. In this paper, a theoretical model based on the autocorrelation tensor shows that in proton radiography of the Weibel-instability-induced magnetic field, the proton flux density on the detection plane can be related to the energy spectrum of the magnetic field. It allows us to extract the main wavelength and mean strength of the two-dimensionally isotropic and stochastic magnetic field directly from proton radiography for the first time. Numerical calculations are conducted to verify our theory and show good consistency between pre-set values and the results extracted from proton radiography.

In traditional Simultaneous Localisation and Mapping (SLAM) algorithms based on Extended Kalman Filtering (EKF-SLAM), the uncertainty of state estimation will increase rapidly with the development of the exploration process and the increase of map area. Likewise, the computational complexity of the EKF-SLAM is proportional to the square of the number of feature points contained in the state variables in a single filtering process. A new SLAM algorithm combining the local submaps and the body-fixed coordinates of the rover is presented in this paper. The algorithm can reduce the computational complexity and enhance computational speed in consideration of the processing capability of the onboard computer. Due to the introduction of local submaps, the algorithm represented in this paper is able to reduce the number of feature points contained in the state variables in each single filtering process. Therefore, the algorithm could reduce the computational complexity and improve the computational speed. In addition, rover body-fixed SLAM could improve the navigation accuracy of a rover and decrease the cumulative linearization error by coordinates transformation during the update process, which is shown in the simulation results.

Annexin A2 (ANXA2) is reported to be associated with cancer development. To investigate the roles ANXA2 plays during the development of cancer, the RNAi method was used to inhibit the ANXA2 expression in caco2 (human colorectal cancer cell line) and SMMC7721 (human hepatocarcinoma cell line) cells. The results showed that when the expression of ANXA2 was efficiently inhibited, the growth and motility of both cell lines were significantly decreased, and the development of the motility relevant microstructures, such as pseudopodia, filopodia, and the polymerization of microfilaments and microtubules were obviously inhibited. The cancer cell apoptosis was enhanced without obvious significance. The possible regulating pathway in the process was also predicted and discussed. Our results suggested that ANXA2 plays important roles in maintaining the malignancy of colorectal and hepatic cancer by enhancing the cell proliferation, motility, and development of the motility associated microstructures of cancer cells based on a possible complicated signal pathway.

The classical Halpern–Läuchli theorem states that for any finite coloring of a finite product of finitely branching perfect trees of height ω, there exist strong subtrees sharing the same level set such that tuples in the product of the strong subtrees consisting of elements lying on the same level get the same color. Relative to large cardinals, we establish the consistency of a tail cone version of the Halpern–Läuchli theorem at a large cardinal (see Theorem 3.1), which, roughly speaking, deals with many colorings simultaneously and diagonally. Among other applications, we generalize a polarized partition relation on rational numbers due to Laver and Galvin to one on linear orders of larger saturation.

Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.

The plerocercoid (sparganum) of Spirometra erinaceieuropaei is the main aetiological agent of human sparganosis. To improve the current knowledge on S. erinaceieuropaei evolution, we performed multi-locus microsatellite typing of sparganum isolates from China for the first time. All available expressed sequence tag (EST) sequences for the Spirometra were downloaded from the GenBank. The identification and localization of microsatellites in ESTs was accomplished by MISA. Based on the selected microsatellites, the genetic structure of 64 sparganum isolates collected from 11 geographical locations in southwest China were investigated through principal component analysis, STRUCTURE analysis and neighbour-joining clustering. A total of 522 non-redundant ESTs containing 915 simple sequence repeats were identified from 12 481 ESTs screened. Five primer pairs were finally selected. Using these loci, a total of 12 alleles were detected in 64 sparganum isolates. Little variability was observed within each of geographical population, especially among isolates derived from Kunming of Yunnan (YN-KM) province. Both STRUCTURE analysis and the clustering analysis supported that two genotypes existed among the sparganum isolates from southwest China. In conclusion, five microsatellite markers were successfully developed, and sparganum population was observed to harbour low genetic variation, further investigation with deeper sampling was needed to elucidate the population structure.

A field study to optimize the nitrogen (N) top-dressing mode of panicle fertilization and improve rice yields was conducted in mid-eastern China. Japonica cultivar Yunongjing-6 was grown and panicle N fertilizer was applied at the beginning of the inverted fourth leaf stage using three different modes: manual broadcast application (BA) on the soil surface as a control treatment, deep application during ditching at a depth of 15 cm (DD) and manual BA on the soil surface during deep ditching (BAD). The activity of soil enzymes, including invertase, urease, phosphatase and catalase, was increased significantly at the jointing, booting and grain-filling stages with the DD and BAD treatments compared with the traditional BA mode. The DD and BAD treatments also increased basal internode and neck-panicle internode bleeding intensity. The DD treatment gave the highest crop yield, increasing the yield by 0.63 and 0.31 t/hm2 in 2011 and 2012, respectively, compared with BA. The results suggest that ditching during panicle N fertilizer application after sun-drying of the fields increases rice yields, most likely by improving the activity of soil enzymes and enhancing the physiological activity of roots and grain weight.

Hepatitis B constitutes a severe public health challenge in China. The Community-based Collaborative Innovation hepatitis B (CCI-HBV) project is a national epidemiological study of hepatitis B and has been conducting a comprehensive intervention in southern Zhejiang since 2009.

The comprehensive intervention in CCI-HBV areas includes the dynamic hepatitis B screening in local residents, the normalised treatment for hepatitis B infections and the upcoming full-aged hepatitis B vaccination. After two rounds of screening (each round taking for 4 years), the initial epidemiological baseline of hepatitis B in Qinggang was obtained, a coastal community in east China. By combining key data and system dynamics modelling, the regional hepatitis B epidemic in 20 years was predicted.

There were 1041 HBsAg positive cases out of 12 228 people in Round 1 indicating HBV prevalence of 8.5%. Of the 13 146 people tested in Round 2, 1171 people were HBsAg positive, with a prevalence of 8.9%. By comparing the two rounds of screening, the HBV incidence rate of 0.192 per 100 person-years was observed. By consulting electronic medical records, the HBV onset rate of 0.533 per 100 person-years was obtained. We generated a simulated model to replicate the real-world situation for the next two decades. To evaluate the effect of interventions on regional HBV prevalence, three comparative experiments were conducted.

In this study, the regional hepatitis B epidemic in 20 years was predicted and compared with HBV prevalence under different interventions. Owing to the existing challenges in research methodology, this study combined HBV field research and simulation to provide a system dynamics model with close-to-real key data to improve prediction accuracy. The simulation also provided a prompt guidance for the field implementation.

Discounting rate refers to people’s tendency to reduce the rate of subjective value from delayed benefit over time. The current study investigates the relationship among belief in a just world (BJW), sense of control, and discounting rate, especially the mediating effect of sense of control between BJW and discounting rate. The study recruited 412 undergraduates to complete a BJW scale, Sense of Control scale, and the Monetary Choice Questionnaire. The results show that (1) BJW positively predicted sense of control, (2) BJW and sense of control were negatively correlated with discounting rate, and (3) sense of control completely mediated the associations between BJW and discounting rate. These findings extend those of prior studies and indicate that a sense of control underlies the association between BJW and discounting rate.

In situ TiB2 particles with polyhedral or near-spherical morphology with more high-index crystal planes exposed were prepared by controlling the addition amount of Sc in commercial pure aluminum matrix. As the content of Sc increased, TiB2 morphology transformed from hexagonal platelets to polyhedral or near-spherical morphology with a decrease in particle size. In the present paper, a simple method to prepare near-spherical in situ TiB2 particles in Al matrix was explored and it was found that the reinforcement distribution was improved significantly. The different growth mechanism of TiB2 particles in Al and Al–Sc systems was discussed. The key reason for the morphology evolution was that the Sc was preferentially adsorbed on ${\bf \left\{ {1{\bf \overline{2}}12} \right\}}$ , ${\bf \left\{ {11\overline{2}0} \right\}}$ , and ${\bf \left\{ {10\overline{1}1} \right\}}$ which would inhibit the growth of these faces effectively and retain a lower-energy state of the polyhedral or quasispherical TiB2 particles in Al–Sc systems.

Seed reserves play vital roles in seed germination and seedling growth and their variation may be related to various environment factors, plant traits and phylogenetic history. Here, the evolutionary correlation associated with seed mass and altitude and carbon (C), nitrogen (N) and phosphorus (P) allocation of seeds among 253 alpine herbaceous plants was tested. In this study, phylogeny had strong limitations on nutrient allocation of seeds across species, and species from younger phylogenetic groups tended to have higher N and P contents, which might be considered as the evolutionary selection of seed plants. Higher seed N and P content would help seedlings to gain more survival chance and stronger competitive capacity, and their progeny would be more likely to be preserved. When phylogeny was considered, altitude only had a significant positive effect on P content, but the negative effects on seed mass were all expressed. The independent effects of altitude and seed mass suggest that the nutrient allocation of seeds might be affected by both environment and plant traits. In addition, altitude and seed mass displayed partial overlapping effects on nutrient allocation of seeds. The negative effects of seed mass were affected slightly by altitude, whereas altitude only had a significant positive effect on P content when seed mass was controlled. Above all, seed P content showed obvious and general correlations with seed mass, altitude and age of clade, which indicated that higher seed P content might be an adaptive selection of species associated with growth and survival of progeny.

The glass surfaces used for optical devices are necessary to have high transparency. Here we propose to take advantage of tube-like SiO2 textures to trap lubricant liquid inside aiming to prepare novel slippery liquid-infused porous surfaces (SLIPS). As a consequence, SLIPS with high transparency were synthesized on glass substrate successfully. The capillary action of unique tubular structure induces the ion migration of adjacent Krytox 100, thus endowing SLIPS with the self-healing property. Moreover, the remarkable slip behavior enables these surfaces to possess the self-cleaning and anti-biofouling performances. The current work might provide a promising candidate for long-term transparent optical devices.

Few studies have examined the association of various types of Fe with colorectal cancer risk. The aim of this study was to investigate different forms and sources of Fe in relation to colorectal cancer risk in a Chinese population. A total of 2138 patients with colorectal cancer and 2144 sex- and age-matched (5-year interval) controls were recruited from July 2010 to November 2017. Dietary information was assessed by face-to-face interviews using a validated FFQ. Multivariable logistic regression was used to estimate the OR and 95 % CI on models. Intake of Fe from plants and Fe from white meat were inversely associated with the risk of colorectal cancer, while haem Fe and Fe from red meat were positively associated with colorectal cancer risk. The multivariable OR for the highest quartile v. the lowest quartile were 0·72 (95 % CI 0·59, 0·87, Ptrend<0·001) for Fe from plants, 0·54 (95 % CI 0·45, 0·66, Ptrend<0·001) for Fe from white meat, 1·26 (95 % CI 1·04, 1·53, Ptrend=0·005) for haem Fe and 1·83 (95 % CI 1·49, 2·24, Ptrend<0·001) for Fe from red meat intake, respectively. However, no significant association was found between the consumption of total dietary Fe, non-haem Fe, Fe from meat and colorectal cancer risk. This study showed that lower intake of Fe from plants and white meat, as well as higher intake of haem Fe and Fe from red meat, were associated with colorectal cancer risk in a Chinese population.

We explore the status of state-of-the-art upconverter materials in the context of improving solar cell performance. We focus on semiconductor upconversion nanostructures that can harvest two separate bands of the solar spectrum and offer a promising path to rational engineering of improved performance and thus improved overall solar energy harvesting.

Photon upconversion is a process in which two low-energy photons are sequentially absorbed and one high-energy photon is emitted. Photon upconversion in both inorganic and organic material platforms has been used to improve solar cell efficiency. Lanthanide-doped salts (inorganic) and triplet–triplet annihilation molecules (organic) have achieved 33% and 60% internal upconversion quantum efficiency, respectively, leading to current density increases of 17 mA/cm2 and 0.86 mA/cm2. However, their performance is limited by their narrow absorption bandwidth (AB) and limited tunability, especially at low photon fluxes. Recently, colloidal semiconductor nanostructures have emerged as a promising material platform for upconversion. The optical absorption in these low-dimensional heterostructures involves both quantum-confined and continuum band states, enabling a much larger AB. Moreover, the techniques of semiconductor heterostructure engineering can be used to optimize performance and to tailor absorption and emission wavelengths. We review the performance and potential impact on solar energy harvesting of upconversion materials, focusing on semiconductor upconverters. We discuss computational models that suggest that semiconductor upconverter nanostructures could have outstanding performance for photovoltaic. We then discuss the current state of the art in semiconductor upconversion morphologies and compositions and provide an outlook on the ways in which nanostructures can be tailored to improve performance for applications.

As the largest industrial and population centre in China, the Pearl River Delta is facing a growing threat of heavy metal pollution from local mining and power industries. This study investigates the distribution and potential health risks of copper (Cu), cadmium (Cd), lead (Pb) and zinc (Zn) in paddy soils and rice at four typical sites. The Nemerow synthetic pollution index (PN) of soils from Fogang, Dabao Mountain, Shaoguan and Lechang were 8.40, 9.10, 4.64 and 10.28, respectively, indicating serious pollution at all four sampling sites. The average concentrations of Cu, Cd, Pb and Zn in rice grains were 2.23, 10.98, 29.84 and 1.62 times their corresponding maximum allowable levels, indicating potential health risks to humans. Cd has greater bioavailability because of its high mobility from soil to roots, and its subsequent transfer to grains. Pb mainly accumulates in roots because of its lower translocation rate from roots to grains. The greatest health risk index for Cd and Pb for adults and children was at the Shaoguan site, probably due to pollution from atmospheric deposition. Cd and Pb had greater health risk indices than Cu and Zn at almost all sites, indicating a major health risk to local people.