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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.
Superior and inferior rice grains have different weights and are located on the upper primary branch and lower secondary branches of the panicle, respectively. To study differences in germination vigour of these two types of grain, a number of factors were investigated from 0 to 48 h of germination. The present study demonstrated that in inferior grains the starch granule structure was looser at 0 h, with full water absorption at 48 h, while in superior grains the structure was tight and dense. Relative water content increased, and dry matter decreased, more rapidly in inferior grains than in superior ones. Abscisic acid and gibberellin levels, as well as α-amylase activity, also changed more rapidly in inferior grains, while soluble sugar content and amylase coding gene expression increased more rapidly in inferior than superior grains during early germination. The expression of OsGAMYB was higher in inferior grains at 24 h but higher in superior grains at 48 h. The phenotypic index of seedlings was higher in seedlings from superior grains at the two-leaf stage. However, the thousand-grain weight and yield per plant in superior and inferior plants showed no significant difference at harvest. The present study indicates that inferior grains germinate faster than superior ones in the early germination stage. Although inferior grains produced weaker seedlings, it is worthwhile using them in rice production due to their comparative yield potential over that of superior grains.
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.
We identified human paleodietary changes from inhabitants of the Guanzhong basin since 8000 BP, based on published carbon and nitrogen isotopic measurements on bones, fauna and plant remains. We also directly measured 14C ages, δ13C and δ15N values from bones unearthed at the Zhouyuan site, west of Guanzhong, in order to reconstruct paleodietary changes of the ancient inhabitants. We found that during the Laoguantai period, animal foods were the main source of nourishment with supplementary plant-derived foods. After this period, plant-derived foods became the main food source, with supplementary animal sources. The development of dry farming led to increased consumption of foxtail millet and broomcorn millet. This trend persisted and marked a fundamental shift from hunting, gathering, and fishing to farming and animal domestication. The dietary trends of the ancient inhabitants also show pronounced regional differences through time. The use of domestic animals was proportionally higher in the eastern part of the Guanzhong region, while wild animals were more common in the west.
X-ray powder diffraction data, unit-cell parameters, and space group for ertapenem side chain, C20H19N3O7S, are reported [a = 4.907(6) Å, b = 18.686(3) Å, c = 22.071(1) Å, α = γ = 90°, β = 90.759(5)°, unit-cell volume V = 2023.82 Å3, Z = 4, ρcal = 1.462 g cm−3, and space group P21/c]. All measured lines were indexed and are consistent with the P21/c space group. No detectable impurity was observed.
Change mode and effects analysis (CMEA) is a powerful technique for measuring product flexibility toward future changes and diminishing the cost of redesign as well as shortening time to market. As a systematic methodology, it provides an in-depth view for the investigation of potential changes, causes, and effects in designs, products, and processes. Traditional CMEA determines the risk priorities of change modes by using change potential number, which requires the risk factors of design flexibility, occurrence, and readiness to be precisely evaluated. However, this is not always possible in real applications due to the uncertainty and subjectivity involved in the early design stages. It has been criticized much for its deficiencies in criteria weighting of the risk factors, change potential number calculation, and risk priorities determination of the change modes. This paper presents a systematic evaluation approach for determining a more rational rank of change modes by combining with the entropy weight method, rough number, and grey relational analysis. In this study, the entropy weight method is adopted to calculate the relative importance of risk factors. Rough number is presented to aggregate individual weights and preferences, and to manipulate the vagueness in the evaluation process. Then a rough number enhanced grey relational analysis is proposed to evaluate the risk ranking of change modes. Finally, a practical example is put forward to validate the performance of the proposed method. The result shows that the proposed change mode evaluation method can effectively overcome the shortcomings of traditional CMEA and strengthen the objectivity of product flexibility measurement.
Previous studies have thoroughly investigated the prevalence and risk factors for completed suicide. In marked contrast is the lack of a better understanding of attempted suicide in the elderly. The aim of this study was to estimate the prevalence of attempted suicide in the elderly and examine the associated factors.
Using a multi-stage cluster sampling approach, a cross-sectional survey of 8,399 elderly house-dwelling residents was conducted in Shanghai, China.
The two-week prevalence of attempted suicide in the elderly was 0.75%. In the bivariate analysis, having no caregivers, depressive, anxiety, sad, fear, obsessive-compulsive and anger symptom, and lower scores on the Barthel Index of Activities of Daily Living and the Lawton Instrumental Activities of Daily Living Scale were significantly associated with an increased risk of attempted suicide in the elderly. In the multivariate analysis, sad and fear symptoms were significantly and independently associated with a higher risk of attempted suicide in the elderly.
The two-week prevalence of attempted suicide in the elderly is relatively high when compared with the annualized or lifetime prevalence reported in China and foreign settings. Elderly individuals with certain mental symptoms should be targeted for suicide prevention and provided with timely mental health support.
This article is devoted to the study of some high-order difference schemes for the distributed-order time-fractional equations in both one and two space dimensions. Based on the composite Simpson formula and Lubich second-order operator, a difference scheme is constructed with convergence in the L1(L∞)-norm for the one-dimensional case, where τ,h and σ are the respective step sizes in time, space and distributed-order. Unconditional stability and convergence are proven. An ADI difference scheme is also derived for the two-dimensional case, and proven to be unconditionally stable and convergent in the L1(L∞)-norm, where h1 and h2 are the spatial step sizes. Some numerical examples are also given to demonstrate our theoretical results.
Based on SDSS and South Galactic Cap U-band Sky Survey (SCUSS) photometry, we try to study the photometric metallicity of the Sagittarius (Sgr) stream in the south Galactic cap. We find that the Sgr stream has a wider metallicity distribution, and that its median metallicity is richer than that of the field halo stars. The neighboring field halo stars in our studied fields can be modeled by a two-Gaussian model, with peaks at [Fe/H]= −1.9 and [Fe/H]= −1.5. The metallicity distribution function (MDF) of the mixed population (Sgr stream and halo stars) has peaks at [Fe/H]= −1.9, [Fe/H]= −1.5 and [Fe/H]= −0.5, respectively.
The carburizing behaviors and mechanisms for Cr35Ni45Nb alloy subjected to different service conditions were studied in a high-temperature vacuum environment. Generally, the carburizing process of an alloy is always accompanied by diffusional heterogeneous reactions regardless of the service condition of the alloy. For a carburized original tube, there is a layered structure at the inner wall of the tube, which is comprised of a M7C3 zone, a M7C3–M23C6 mixed zone, and a M23C6 zone with different morphologies. However, for a 6-year tube (short for a tube serviced for 6 years), the composite oxide layers formed previously act as effective barriers to carbon infiltration. Moreover, the Cr2O3 scale tended to be carbonized to form carbide scale to spall from the surface in a reducing environment, while the SiO2 kept stable all along. Once the oxide layers were removed or carbonized enough, inconceivable internal carburization occurred widely.
Hepcidin, a key regulator of Fe homeostasis, is an ideal drug target for treating patients with Fe disorders such as haemochromatosis, anaemia of chronic inflammation and Fe-deficiency anaemia. However, whether (and how) traditional Chinese black foods (e.g. black soyabeans) target hepcidin and improve Fe-deficiency anaemia remains unclear. Herein, we report that black soyabean seed coat extract (BSSCE) can potently inhibit the in vitro and in vivo expression of hepcidin. In the present study, in cells treated with 200 μg/ml BSSCE, hepcidin expression was found to be reduced to only 6 % of the control levels (P< 0·01). An AIN-76A diet containing 2 % BSSCE was fed to 8-week-old male C57BL/6 mice for 0, 1, 7, 15 or 30 d; importantly, compared with the day 0 group, the day 7 group exhibited nearly a 50 % decrease in hepatic hepcidin expression (P< 0·01), a 35 % decrease in splenic Fe concentrations (P< 0·05) and a 135 % increase in serum Fe concentrations (P< 0·05). Mechanistically, the effect of BSSCE on hepcidin expression was mediated via a reduction in the phosphorylation levels of mothers against decapentaplegic homolog proteins (Smad)1/5/8. Consequently, the mice in the day 30 group exhibited large increases in erythrocyte counts (111 % v. day 0, P< 0·01), Hb concentrations (109 %, P< 0·01) and haematocrit values (108 %, P< 0·01). In conclusion, these results indicate that black soyabean extract regulates Fe metabolism by inhibiting the expression of hepcidin. This finding can be used to optimise the intervention of patients with hepcidin-related diseases, including Fe-deficiency anaemia.
This paper proposes a new effective kinematics method based on the dynamic visual window (DVW) for a surgical robot that is equipped with two instrument arms and one laparoscope arm, to enable doctors to achieve operations with their visual habits under the laparoscopic visual environment. The problem of the consistency principle between the doctor's operations under the visual window's feedback and the master–slave operations of the surgical robot is solved. The kinematics models of the surgical robotic arms are established, and the new kinematics methods based on the DVW of the laparoscope and instrument arms are proposed according to their inverse kinematics with respect to the visual coordinate system. Finally, the proposed kinematics method is verified by simulation experiments based on the theoretical algorithm and the mechanism model; the multiple sets of the simulation data are presented to illustrate the correctness and feasibility of the new method in this research.
Using ~2200 BATC main sequence (MS) stars which include SDSS stellar atmospheric parameters, we develop the polynomial photometric calibration method to evaluate the stellar effective temperature and metallicity for BATC data. This calibration method has been applied to about 160 000 MS stars. The mean stellar metallicity smoothly decreases from −0.65 to −0.78 dex in the interval 0.5 < |Z| ≤ 2 kpc. Metallicity distributions in the halo and the thick disk seem invariant with the distance from the Galactic plane.
Based on the South Galactic Cap U-band Sky Survey (SCUSS) and SDSS observation, we adopted the star-count method to analyze the stellar distribution in different directions of the Galaxy. We find that these model parameters may be variable with observed direction, which cannot simply be attributed to statistical errors.
The chemical extraction of soil organic carbon (SOC) fractions from soils often does not produce satisfactory results for radiocarbon dating. In this study, a sequential pyrolysis technique was investigated. The soil was pyrolyzed at temperatures of 200, 400, 600, and 800 °C to partition organic carbon into pyrolytic volatile (Py-V) and pyrolytic residue (Py-R) fractions. The preliminary results show that the 14C dates of both fractions become progressively older as the pyrolysis temperature is increased. In addition, the ages of the Py-V fractions are consistently younger than the corresponding Py-R fractions extracted at the same temperature. Experimental results of known-age paleosol samples indicate that the Py-V fractions obtained between 600 and 800 °C yield the most reliable ages. This technique provides a new approach to improve the accuracy of 14C dating of loess-paleosol sequences.
China's population has been ageing rapidly since the 1980s, with 178 million older persons (60 years or over) in 2010 and 450 million expected by 2050. The sheer size of the ageing population means that there is an urgent need to tackle ageing issues and improve social policies in order to achieve intergenerational solidarity, sustainable development and a harmonious society. This paper will summarise the issues and debates in the past decade on social exclusion and discuss the progress of policies and practices with respect to social inclusion. The focus of discussion will be on (a) ways to improve the social security system so as to achieve a better balance of formal and informal supports, (b) development of community services for meeting the needs of older people living alone or having special needs in daily living, and (c) new initiatives for balancing formal support and filial piety, taking into account the younger generation's expectation that in order to maintain the important role of filial piety in modern China, the ability to fulfil filial obligations must be supported by the development of formal support beyond the family. In addition, some emerging issues and challenges will also be discussed.
Based on BATC and SDSS photometric data, we adopt the spectral energy distribution (SED) fitting method to evaluate stellar metallicities in the Galaxy. We find that the mean metallicity shifts from metal-rich to metal-poor with the increase of distance from the Galactic Centre.
Based on the South Galactic Cap U-band Sky Survey (SCUSS) and SDSS observations, we adopted the star-count method to analyze the stellar distribution in different directions of the Galaxy. We find that the scale height of the disk may be variable with the observed direction, which cannot simply be attributed to statistical errors. The main reason can be possibly attributed to the disk (mainly the thick disk) being flared, with a scale height increasing with radius. The axis ratio of the Galactic halo is in the range 0.4-0.6. This finding supports Galactic models with a flattened inner halo, partly formed through a merger early in the Galaxy's history.