Given the possibility of cultural differences in the meaning and levels of gratitude among children, we evaluated the measurement invariance of the Gratitude Questionnaire–5 (GQ–5) and differences in latent means across adolescents from two distinct cultures, China and America. Data were obtained from 1,991 Chinese and 1,685 American adolescents. Confirmatory factor analysis and multigroup confirmatory factor analysis were performed to examine the factor structure and the measurement equivalence across Chinese and American adolescents. The Cronbach’s alpha and Item-total Correlations of the GQ–5 were also evaluated. Results of confirmatory factor analyses provided support for the expected one-factor structure. Also, a series of multi-group confirmatory factor analyses supported full configural invariance, full metric invariance, and partial scalar invariance between the two groups. Furthermore, the findings suggested that the GQ–5 is suitable for conducting mean level comparisons. The subsequent comparison of latent means revealed that the Chinese adolescents reported significantly lower gratitude than American adolescents.

In this article, the electron trapping and acceleration in the wake field driven by an ultrarelativistic hollow electron beam is studied. When the hollow driver injects into plasma, there is a doughnut-shaped electron bubble formed because of the existence of a special ‘backflow’ beam in the centre of the electron bubble. At the same time, there is a transverse convergence of the hollow driver, which leads to the weakening of the backflow beam. This results in a local electron density transition at the rear of the bubble. During this process, there is an expansion of the longitudinal electron bubble size, and a bunch of background electrons is trapped by the wake field at the rear of the bubble. The tracks for the trapped electrons show that there are two sources: one is from the bubble sheath and the other is from the unique backflow beam. In the particle-in-cell simulation where the driving beam has initial energy of $1.0$ GeV per particle, the trapped beam can be accelerated to energy of more than $1.5$ GeV per particle and the corresponding transformer ratio is $1.5$. With the increase of driving beam energy up to $40.0$ GeV, a transformer ratio of $1.4$ still can be achieved. By adjusting the hollow beam density, it is possible to control the trapped beam charge value and beam quality, such as its energy spread and transverse emittance.

This study examined the contribution of long-term use of Lipiodol capsules, as a supplement to iodised salt to the control of iodine deficiency disorders among women in Xinjiang of China. A total of 1220 women across Kashgar, Aksu, Turpan and Yili Prefectures were surveyed in 2017. Lipiodol capsules were administered twice yearly in Kashgar and once yearly in Aksu and Turpan, but not in Yili. Urinary iodine concentration (UIC), free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyroglobulin antibody, thyroid peroxidase antibody and thyroid volume values were assessed. All the women in the four areas were in a state of non-iodine deficiency by UIC. The UIC were higher than adequate in Kashgar and Aksu (619·4 v. 278·6 μg/l). Thyroid hormone levels differed significantly in Turpan and Yili (FT3: 4·4 v. 4·6 pmol/l, FT4: 13·8 v. 14·2 pmol/l, TSH: 2·0 v. 2·7 mIU/l), but did not differ significantly in Kashgar, Aksu and Yili. The four areas did not differ significantly with regard to thyroid nodules, autoimmune thyroiditis or goitre. However, the detection rates of subclinical hypothyroidism (16·6 %) and total thyroid dysfunction (25·4 %) were higher among women in Yili. The supplementation with Lipiodol capsules had improved the iodine nutrition status of women in iodine-deficient areas of Xinjiang since 2006. To avoid negative effects of excess iodine, we suggest a gradual discontinuation of Lipiodol capsules in women with special needs based on the existing iodine nutrition level of local women.

Non-communicable diseases (NCDs) including obesity, diabetes, and allergy are chronic, multi-factorial conditions that are affected by both genetic and environmental factors. Over the last decade, the microbiome has emerged as a possible contributor to the pathogenesis of NCDs. Microbiome profiles were altered in patients with NCDs, and shift in microbial communities was associated with improvement in these health conditions. Since the genetic component of these diseases cannot be altered, the ability to manipulate the microbiome holds great promise for design of novel therapies in the prevention and treatment of NCDs. Together, the Developmental Origins of Health and Disease concept and the microbial hypothesis propose that early life exposure to environmental stimuli will alter the development and composition of the human microbiome, resulting in health consequences. Recent studies indicated that the environment we are exposed to in early life is instrumental in shaping robust immune development, possibly through modulation of the human microbiome (skin, airway, and gut). Despite much research into human microbiome, the origin of their constituent microbiota remains unclear. Dust (also known as particulate matter) is a key determinant of poor air quality in the modern urban environment. It is ubiquitous and serves as a major source and reservoir of microbial communities that modulates the human microbiome, contributing to health and disease. There are evidence that reported significant associations between environmental dust and NCDs. In this review, we will focus on the impact of dust exposure in shaping the human microbiome and its possible contribution to the development of NCDs.

We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults. We conducted a nested case–control study, including 231 patients with incident cancer and 231 matched controls during a median 4·5-year follow-up of the China Stroke Primary Prevention Trial. There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dl increases: OR 0·79; 95 % CI 0·69, 0·91). When compared with participants in the first quartile of retinol (< 52·3 μg/dl), a significantly lower cancer risk was found in participants in quartile 2–4 ( ≥ 52·3 μg/dl: OR 0·31; 95 % CI 0·13, 0·71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dl increases: OR 0·89; 95 % CI 0·60, 1·31) in participants with retinol < 68·2 μg/dl, and then increased significantly with retinol (per 10 μg/dl increase: OR 1·65; 95 % CI 1·12, 2·44) in participants with retinol ≥ 68·2 μg/dl. In conclusion, there was a significant inverse dose–response association between plasma retinol and the risk of digestive system cancers. However, a U-shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point approximately 68·2 μg/dl).

Ti–47Al samples with a diameter of 18 mm are obtained by electromagnetic confinement and directional solidification at different growth velocities. Controlled by a Ti–43Al–3Si seed, the α grains are aligned well and the parallel lamellar microstructure is obtained at the growth velocity of 10 μm/s. With the growth velocity increases to 25 and 50 μm/s, although the lamellar microstructures are still aligned well in the initial transition stage, the lamellar alignment fails due to the nucleation and growth of new β and α grains and then the inclined and perpendicular lamellar microstructures form eventually. The room temperature tensile properties of the different lamellar microstructures are measured and the results show that the desired lamellar microstructure has a tensile strength of 693 MPa and an elongation of 10.0% simultaneously. They are the maximum values that have been reported in binary γ-TiAl alloys so far and are far higher than those of the other two types of lamellar microstructures. The fracture behaviors of the lamellar microstructures are checked by scanning electron microscopy and transmission electron microscopy. Two models are used to illustrate the fracture mechanism of the different lamellar structures.

In this paper, we introduce a lower extremity exoskeleton CUHK-EXO that is developed to help paraplegic patients, who have lost the motor and sensory functions of their lower limbs to perform basic daily life motions. Since the sit-to-stand and stand-to-sit (STS) motion is the first step for paraplegic patients toward walking, analysis of the exoskeleton's applicability to the STS motion assistance is performed. First, the human-exoskeleton system (HES) is modeled as a five-link model during the STS motion, and the center of pressure (COP) on the ground and center of gravity of the whole system are calculated. Then, a description of the CUHK-EXO hardware design is presented, including the mechatronics design and actuator selection. The COP position is an important factor indicating system balance and wearer's comfort. Based on the COP position, a trajectory online modification algorithm (TOMA) is proposed for CUHK-EXO to counteract disturbances, stabilize system balance, and improve the wearer's comfort in the STS motion. The results of STS motion tests conducted with a paraplegic patient demonstrate that CUHK-EXO can provide a normal reference pattern and proper assistive torque to support the patient's STS motion. In addition, a pilot study is conducted with a healthy subject to verify the effectiveness of the proposed TOMA under external disturbances before future clinical trials. The testing results verify that CUHK-EXO can counteract disturbances, and help the wearer perform the STS motion safely and comfortably.

Effects of traveling magnetic field (TMF) on freckle formation of directionally solidified Pb–Sn alloys were investigated experimentally and numerically. The experimental results demonstrated that freckles could form without any magnetic field and with the upward TMF. In the former case, the formation location is the center. In the latter case, it diverted from the center to the surface with the increasing intensity of TMF. However, freckle could not form under the downward TMF. Numerical results indicated that the change of the formation location under upward TMF should be attributed to the different solid/liquid interface shape, and no formation under downward TMF should be attributed to the convection intensity driven by TMF. These magnetic fields are used to modulate melt flow, which is similar to the effects of the gravity. For eliminating freckle, a microgravity environment can be established under the suitable downward TMF.

The volatile compounds of crofton weed infested by cotton aphids and sprayed with MeJA were collected and analyzed by the TCT-GC/MS technique. The healthy weeds were controls. Seventeen volatiles identified from crofton weed included green leaf odors, monoterpenes and sequiterpenes, and oxo-compounds. Camphene, 2-carene, α-phellandrene, ρ-cymene, and caryophyllene were the major volatiles and constituted about 77% of the total volatile emissions from the control. In the aphid-infested weeds, no new induced component was found. Among the terpenes, ρ-cymene increased markedly in the infested weeds compared with the control, whereas all sesquiterpenes decreased markedly. Levels of endogenous JA in leaves and young stems of the aphid-infested weeds were markedly higher than in the control, whereas both endogenous SA level and ABA level were not significantly different. MeJA sprayed on crofton weed with the aphid infestation had a similar effect on volatile emissions. It is suggested that JA was one of the most important signals in crofton weed and could regulate the emission of volatile compounds.

In this paper, field effect transistors (FET) based on different kinds of non-graphene materials are introduced, which are MoS2, WSe2 and black phosphorus (BP). Those devices have their unique features in fabrication process compared with conventional FETs. Among them, MoS2 FET shows better electrical characteristics by applying a SiO2 protective layer; WSe2 FET is fabricated based on a new low pressure chemical vapor deposition (LPCVD) method; BP FET acquires high on/off ratio and high hole mobility by using a simple dry transfer method. Those novel non-graphene materials inspire new design and fabrication process of basic logic device.

Recent studies have suggested an association between vitamin D and non-alcoholic fatty liver disease (NAFLD); however, some results are subject to debate. This study was carried out to evaluate the correlation between NAFLD and vitamin D in men and women in East China. The data were obtained from a cross-sectional study that focused on the health and metabolic status of adults in sixteen areas of East China. According to ultrasonic assessments, the patients were divided into normal and NAFLD groups. Demographic characteristics and biochemical measurements were obtained. Binary logistic regression analysis was used to explore the association. In total, 5066 subjects were enrolled, and 2193 (43·3 %) were diagnosed with NAFLD; 84·56 % of the subjects showed vitamin D deficiency. Subjects with high vitamin D levels had a lower prevalence of NAFLD, particularly male subjects. Within the highest quartile of vitamin D levels, the prevalence of NAFLD was 40·8 %, whereas the lowest quartile of vitamin D levels showed a prevalence of 62·2 %, which was unchanged in women across the vitamin D levels. Binary logistic analysis showed that decreased vitamin D levels were associated with an increased risk of NAFLD (OR 1·54; 95 % CI 1·26, 1·88). This study suggests that vitamin D levels are significantly associated with NAFLD and that vitamin D acts as an independent factor for NAFLD prevalence, particularly in males in East China. Vitamin D interventional treatment might be a new target for controlling NAFLD; elucidating the mechanism requires further research.

The cultivation of rice has had a major impact on both societies and their environments in Asia, and in China in particular. Phytolith assemblages from three Neolithic sites in the Lower Yangtze valley reveal that in early rice fields the emphasis was on drainage to limit the amount of water and force the rice to produce seed. It was only in the later third millennium BC that the strategy changed and irrigated paddies came into use. The results demonstrate that plant remains, including weed assemblages, can reveal wetter or drier growing conditions, showing changes in rice cultivation from flooded and drained fields to large, intensively irrigated paddies.

Nanogenerators (NGs) have great potential to solve the problems of energy depletion and environmental pollution. Here, two types of flexible nanogenerators (FNGs) based on graphene oxide (GO) and multiwall carbon nanotubes (MW-CNTs) are presented. The peak output voltage and current of GO based FNG reached up to 2 V and 30 nA, respectively, under 15 N force at 1 Hz. Moreover, the output voltage could be improved to 34.4 V when the frequency was increased to 10 Hz. It was also found the output voltage increased from 0.1 V to 2.0 V using a released GO structure. The other FNG was made by MW-CNTs mixed with ZnO nanoparticles (NPs). Its output voltage and power reached up to 7.5 V and 18.75 mW, respectively, which is much larger than that of bare ZnO based FNG. Furthermore, a peak voltage of 30 V could be gained by stamping one’s foot on the FNG. Finally, a modified NG was fabricated using four springs and two flexible layers. As a result, the voltage and power reached up to 9 V and 27mW, respectively. These works may bring out broad applications in energy harvesting.

In this paper, we first summarise the progress for the famous Chern conjecture, and then we consider n-dimensional closed hypersurfaces with constant mean curvature H in the unit sphere n+1 with n ≤ 8 and generalise the result of Cheng et al. (Q. M. Cheng, Y. J. He and H. Z. Li, Scalar curvature of hypersurfaces with constant mean curvature in a sphere, Glasg. Math. J. 51(2) (2009), 413–423). In order to be precise, we prove that if |H| ≤ ϵ(n), then there exists a constant δ(n, H) > 0, which depends only on n and H, such that if S0 ≤ S ≤ S0 + δ(n, H), then S = S0 and M is isometric to the Clifford hypersurface, where ϵ(n) is a sufficiently small constant depending on n.

We tested cross-species amplification of 68 existing microsatellite loci in 6 species of the Sparidae family: Acanthopagrus butcheri, Sparus aurata, Pagrus auratus, Chrysophrys major, Pagellus bogaraveo, Pagellus erythrinus and one species of Bothidae, Paralichthys olivaceus. Of the 68 loci screened, sixteen were found to be polymorphic when tested in 20 individual black sea bream, Acanthopagrus schlegeli. The number of alleles per locus ranged from 2 to 9, and the observed and expected heterozygosity ranged from 0.55 to 0.95, and from 0.58 to 0.87, respectively. Our results show that cross-species amplification of known microsatellite loci in closely related species is a highly promising source of microsatellite markers for A. schlegeli.

Prompted by a recent article by Jiang and Liu in Antiquity (80, 2006), Dorian Fuller and his co-authors return to the question of rice cultivation and consider some of the difficulties involved in identifying the transition from wild to domesticated rice. Using data from Eastern China, they propose that, at least for the Lower Yangtze region, the advent of rice domestication around 4000 BC was preceded by a phase of pre-domestication cultivation that began around 5000 BC. This rice, together with other subsistence foods like nuts, acorns and waterchestnuts, was gathered by sedentary hunter-gatherer-foragers. The implications for sedentism and the spread of agriculture as a long term process are discussed.