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This paper presents a comprehensive study of the zircon geochronology, geochemistry and Sr–Nd isotope geology of Devonian mafic rocks developed in the East Kunlun orogenic belt, northern Tibetan Plateau, and reveals their mantle sources, petrogenesis and geodynamic implications for continental exhumation. The zircon geochronology of typical samples indicates that these mafic rocks crystallized at 406∼408 Ma. They can be classified into two different groups based on petrographic observations and geochemical compositions. Group 1 rocks exhibit low TiO2 and FeOt contents and Nb/Y ratios and have enriched mid-ocean ridge basalt (E-MORB)-like compositions with slight negative Nb and Ta anomalies. However, Group 2 rocks have distinctly high TiO2 and FeOt contents and Nb/Y ratios, comparable to typical Fe–Ti-rich mafic rocks worldwide. All the samples exhibit weak enrichments in light rare earth elements, Nb and Ta relative to the primitive mantle. Based on geochemical and isotopic studies, Group 1 rocks are suggested to be derived from depleted asthenospheric mantle that was metasomatized by c. 3–5 % continental crustal components, while Group 2 rocks originated from partial melting of enriched lithospheric mantle. The high contents of Fe, Ti and Nb for Group 2 rocks could be attributed to a high degree of olivine crystallization under low fO2 conditions with delayed nucleation of Fe–Ti oxides. Combining those results with other geological data, we conclude that slab break-off was the key factor causing exhumation of eclogites and triggering flare-up of the Devonian magmatism, and that continental collision or continental subduction may have initiated at 431∼436 Ma.
This study attempts to figure out the seasonality of the transmissibility of hand, foot and mouth disease (HFMD). A mathematical model was established to calculate the transmissibility based on the reported data for HFMD in Xiamen City, China from 2014 to 2018. The transmissibility was measured by effective reproduction number (Reff) in order to evaluate the seasonal characteristics of HFMD. A total of 43 659 HFMD cases were reported in Xiamen, for the period 2014 to 2018. The median of annual incidence was 221.87 per 100 000 persons (range: 167.98/100,000–283.34/100 000). The reported data had a great fitting effect with the model (R2 = 0.9212, P < 0.0001), it has been shown that there are two epidemic peaks of HFMD in Xiamen every year. Both incidence and effective reproduction number had seasonal characteristics. The peak of incidence, 1–2 months later than the effective reproduction number, occurred in Summer and Autumn, that is, June and October each year. Both the incidence and transmissibility of HFMD have obvious seasonal characteristics, and two annual epidemic peaks as well. The peak of incidence is 1–2 months later than Reff.
Malnutrition and acute kidney injury (AKI) are common complications in hospitalized patients, and both increase mortality; however, the relationship between them is unknown. This is a retrospective propensity score matching study enrolling 46,549 inpatients, aimed to investigate the association between Nutritional Risk Screening 2002 (NRS-2002) and AKI, and to assess the ability of NRS-2002 and AKI in predicting prognosis. In total, 37,190 (80%) and 9,359 (20%) patients had NRS-2002 scores < 3 and ≥ 3, respectively. Patients with NRS-2002 scores ≥ 3 had longer lengths of stay (12.6±7.8 days vs. 10.4±6.2 days, P < 0.05), higher mortality rates (9.6% vs. 2.5%, P<0.05), and higher incidence of AKI (28% vs. 16%, P < 0.05) than normal nutritional patients. The NRS-2002 showed a strong association with AKI, that is, the risk of AKI changed in parallel with the score of the NRS-2002. In short- and long-term survival, patients with a lower NRS-2002 score or who did not have AKI achieved a significantly lower risk of mortality than those with a high NRS-2002 score or AKI. Univariate Cox regression analyses indicated that both the NRS-2002 and AKI were strongly related to long-term survival (area under the curve (AUC) 0.79 and 0.71) and that the combination of the two showed better accuracy (AUC 0.80) than the individual variables. In conclusion, malnutrition can increase the risk of AKI, and both AKI and malnutrition can worsen the prognosis, that the undernourished patients who develop AKI yield far worse prognosis than normal nutritional patients.
The Ghana/Côte d'Ivoire case is the first time that an ITLOS ad hoc chamber has addressed the lawfulness of unilateral hydrocarbon activities in a disputed maritime area. This paper analyzes the Chamber's ruling on Côte d'Ivoire's submission no. 2, which covers several important issues: the jurisdiction of the Chamber to decide on submission no. 2, the alleged violation of sovereign rights, and the alleged violation of Article 83(3) of UNCLOS. The paper argues that the Chamber's jurisdictional basis of forum prorogatum is questionable, and that there are inconsistent approaches between the Judgment and the Order of the provisional measures. Additionally, there are not only inconsistent understandings of the “Ivorian maritime area” within the same submission no. 2 by the Chamber, but also a logical gap in the Chamber's reasoning with regard to submission no. 2(iii). Consequently, the Chamber's inconsistent approaches may jeopardize the persuasiveness of its judgment.
Recently, we introduced an epoxy group to mebendazole by a reaction with epichlorohydrin and obtained two isoforms, mebendazole C1 (M-C1) and mebendazole C2 (M-C2). The in vitro effects of mebendazole derivatives at different concentrations on Echinococcus multilocularis protoscoleces and metacestodes as well as cytotoxicity in rat hepatoma (RH) cells were examined. The results demonstrated that the solubility of the two derivatives was greatly improved compared to mebendazole. The mortality of protoscoleces in vitro reached to 70–80% after 7 days of exposure to mebendazole or M-C2, and M-C2 showed higher parasiticidal effects than mebendazole (P > 0.05). The parasiticidal effect of M-C1 was low, even at a concentration of 30 µm. The percentage of damaged metacestodes that were treated with mebendazole and M-C2 in vitro at different concentrations were similar, and M-C1 exhibited insignificant effects on metacestodes. Significant morphological changes on protoscoleces and metacestodes were observed after treatment with mebendazole and M-C2. In addition, the introduction of an epoxy group to mebendazole also reduced its cytotoxicity in RH cells. Our results demonstrate that the introduction of an epoxy group not only improved the solubility of mebendazole, but also increased its parasiticidal effects on E. multilocularis and reduced its cytotoxicity in RH cells.
The hydrogen embrittlement of 12Cr2Mo1R(H) steel at different strain rates were investigated after hydrogen precharging for 4 h in a 0.5 M H2SO4 solution with 2 g/L ammonium thiocyanate. Results showed that the embrittlement index increased and gradually reached a relative stable value of about 20% at the strain rate of 5 × 10−5 s−1 with the decrease of strain rates. SEM images depicted small and deep flakes at high strain rates, while flakes grew larger at slow strain rates. Most hydrogen-induced cracks (HICs) were transgranular fracture through lath grain of bainitic ferrite. High strain field surrounds the crack tips, which makes the crack tips of two close and parallel cracks deflect toward each another and even form crack coalescence. The electron backscatter diffraction technique was used to investigate the effects of grain boundaries, recrystallization fraction, kernel average misorientation map, texture component, and coincidence site lattice boundaries on the HIC propagation. High densities of dislocations and strain concentrations were found around the cracks, where grains are highly sensitive to HIC.
The prevalence of impaired fasting glucose (IFG) and diabetes mellitus (DM) has reportedly increased significantly among Chinese children and adolescents. We aimed to examine the prevalence of IFG and DM, the disparities in sex and region and related risk factors among Chinese children and adolescents. A total of 16 434 Chinese children aged 6–17 years were selected from a national cross-sectional survey, and fasting glucose was measured for all participants. Overall, mean fasting plasma glucose (FPG) concentration was (4·64 (sd 0·51)) mmol/l, and the prevalence of DM and IFG was 0·10 and 1·89 %, respectively. Compared with girls, boys had higher FPG concentration (4·69 v. 4·58 mmol/l, r 0·107, P<0·001) and IFG prevalence (2·67 v. 1·07 %, rφ 0·059, P<0·001). Compared with rural children and adolescents, urban children and adolescent had higher FPG concentration (4·65 v. 4·62 mmol/l, r 0·029, P<0·001) and DM prevalence (0·15 v. 0·05 %, rφ 0·016, P<0·01). In addition, self-reported fried foods intake and overweight/obesity were positively associated with IFG, and the proportion of consuming fried foods more than or equal to once per week and overweight/obesity prevalence in boys and urban children and adolescents were significantly higher than girls and rural children and adolescents, respectively (P<0·05). Although the prevalence of IFG and DM was relatively low in Chinese children and adolescents, sex and region disparities were observed, which may be associated with differences in overweight/obesity prevalence and dietary factors.
Invasive smooth cordgrass (Spartina alterniflora Loisel) eradication is important for the health of many coastal ecosystems. An integrated regime of continuous submergence after clear mowing, with three interval levels between mowing and submergence (5, 10, and 15 d) and three submergence depths (20, 30, and 50 cm), was implemented in cofferdams enclosing invader populations along a Chinese coast. In July of the following year, after the roots of mowed S. alterniflora had been submerged for 12 mo, some ramets grew under the regime with an interval of 15 d and the regime with a submergence depth of 20 cm, but no ramets occurred under the regimes with submergence depths of 30 or 50 cm and intervals of 5 or 10 d. Four crab species were documented: Helice tridens tientsinensis Rathbun, Sesarma dehaani H. Milne-Edwards, Ocypode stimpsoni Ortmann, and Chiromantes haematocheir de Haan. Biomass and abundance values of crab species in the cofferdams were similar to those in the mudflats but different from those in smooth cordgrass populations. Thus, the treatment of submergence after mowing, which was implemented in the cofferdams, can control S. alterniflora and provide a mudflat-like habitat that promotes crab recovery if this treatment uses the proper combination of submergence depth and interval between mowing and submergence.
A coaxial-output rolled strip pulse-forming line (RSPFL) with a dry structure is researched for the purpose of miniaturization and all-solid state of pulse-forming lines (PFL). The coaxial-output RSPFL consists of a coaxial-output electrode (COE) and a rolled strip line (RSL). The COE is characterized by quasi-coaxial structure, making the output pulse propagate along the axial direction with a small output inductance. The RSL is rolled on the COE, whose transmission characteristics are analyzed theoretically. It shows that the RSL can be regarded as a planar strip line when the rolling radius of the strip line is larger than 60 times of the thickness of the insulation dielectric layer of RSL. CST modeling was carried out to simulate the discharging characteristic of the coaxial-output RSPFL. It shows that the coaxial-output RSPFL can deliver a discharging pulse with a rise time <6 ns when the impedance of the RSL matches that of the COE, which confirms the theoretical analysis. A prototype of the coaxial-output RSPFL was developed. A 49-kV discharging pulse on a matched load was achieved when it was charged to 100 kV. The discharging waveform has a pulse width of 32 ns, with a rise time of 6 ns, which is consistent with the simulation waveform. An energy-storage density of 1.9 J/L was realized in the coaxial-output RSPFL. By the method of multi-stage connection in series, a much higher output voltage is convenient to be obtained.
Both fibronectin (FN) and filamentous actin (F-actin) fibers play a critical role for endothelial cells (ECs) in responding to shear stress and modulating cell alignment and functions. FN is dynamically coupled to the F-actin cytoskeleton via focal adhesions. However, it is unclear how ECs cooperatively remodel their subcellular FN matrix and intracellular F-actin cytoskeleton in response to shear stress. Current studies are hampered by the lack of a reliable and sensitive quantification method of FN orientation. In this study, we developed a MATLAB-based feature enhancement method to quantify FN and F-actin orientation. The role of F-actin in FN remodeling was also studied by treating ECs with cytochalasin D. We have demonstrated that FN and F-actin codistributed and coaligned parallel to the flow direction, and that F-actin alignment played an essential role in regulating FN alignment in response to shear stress. Our findings offer insight into how ECs cooperatively remodel their subcellular ECM and intracellular F-actin cytoskeleton in response to mechanical stimuli, and are valuable for vascular tissue engineering.
The seasonal cycle of fast ice thickness in Prydz Bay, East Antarctica, was observed between March and December 2012. In March, we observed a 0.16 m thickness gain of 0.22 m-thick first-year ice (FYI), while 1.16 m-thick second-year ice (SYI) nearby simultaneously ablated by 0.59 m. A 1-D thermodynamic sea-ice model was applied to identify the factors that led to the simultaneous growth of FYI and melt of SYI. The different evolutions were explained by the difference in the conductive heat flux between the FYI and SYI. As the FYI was thin, there was a large temperature gradient between the ice base and the colder ice surface. This generated an upward conductive heat flux, which was larger than the heat flux from the ocean to the ice base, yielding basal growth of ice. In the case of the thicker SYI the temperature gradient and, hence, the conductive heat flux were smaller, and not sufficient to balance the oceanic heat flux at the ice base, yielding basal ablation. Penetration of solar radiation affected the conductive heat flux in both cases, and the model results were sensitive to the initial ice temperature profile and the uncertainty of the oceanic heat flux.
The Wuhan Pre/Post-Natal Twin Birth Registry (WPTBR) is one of the largest twin birth registries with comprehensive medical information in China. It recruits women from the first trimester of pregnancy and their twins from birth. From January 2006 to May 2016, the total number of twins enrolled in WPTBR is 13,869 twin pairs (27,553 individuals). The WPTBR initiated the Wuhan Twin Birth Cohort (WTBC). The WTBC is a prospective cohort study carried out through incorporation of three samples. The first one comprises 6,920 twin pairs, and the second one, 6,949 twin pairs. Both are population-based samples linked to the WPTBR and include pre- and post-natal information from WPTBR. The second sample includes neonatal blood spots as well. Using a hospital-based approach, we recently developed a third sample with a target enrolment of 1,000 twin pairs and their mothers. These twins are invited, via their parents, to participate in a periodic health examination from the first trimester of pregnancy to 18 years. Biological samples are collected initially from the mother, including blood, urine, cord blood, cord, amniotic fluid, placenta, breast milk and meconium, and vaginal secretions, and later from the twins, including meconium, stool, urine, and blood. This article describes the design, recruitment, follow-up, data collection, and measures, as well as ongoing and planned analyses at the WTBC. The WTBC offers a unique opportunity to follow women from prenatal to postnatal, as well as follow-up of their twins. This cohort study will expand the understanding of genetic and environmental influences on pregnancy and twins’ development in China.
In this paper, a newnotion of scalar curvature for a Finsler metric
is introduced, and two conformal invariants
are defined. We prove that there exists a Finsler metric with constant scalar curvature in the conformal class of
if the Cartan torsion of
is sufficiently small and
is the Yamabe constant of the standard sphere.
Although the brittle material in analogue models is characterized by a linear Navier-Coulomb behaviour and rate-independent deformation, the geometry and style of deformation in accretionary wedges is sensitive to shortening velocity. In this study we have constructed a series of analogue models with various shortening velocities in order to study the influence of shortening velocity on the geometry and kinematics of accretionary wedges. Model results illustrate how shortening velocity has an important influence on the geometry and kinematics of the resulting wedge. In general, for models having similar bulk shortening, the accretionary wedges with higher velocities of shortening are roughly steeper, higher and longer, as well as having larger critical wedge angles and height. It accommodates a number of foreland-vergent thrusts, larger fault spacing and displacement rates than those of low- to medium-velocity shortening, which indicates a weak velocity-dependence in geometry of the wedge. Moreover, models with a high velocity of shortening undergo larger amounts of volumetric strain and total layer-parallel shortening than models with low- to medium-velocity shortening. The former accommodate a greater development of back thrusts and asymmetric structures; a backwards-to-forwards style of wedge growth therefore occurs in the frontal zone under high-velocity shortening.
The aim of this study was to assess the diagnostic value of plasma N-terminal connective tissue growth factor in children with heart failure.
Methods and results
Plasma N-terminal connective tissue growth factor was determined in 61 children, including 41 children with heart failure, 20 children without heart failure, and 30 healthy volunteers. The correlations between plasma N-terminal connective tissue growth factor levels and clinical parameters were investigated. Moreover, the diagnostic value of N-terminal connective tissue growth factor levels was evaluated. Compared with healthy volunteers and children without heart failure, plasma N-terminal connective tissue growth factor levels were significantly elevated in those with heart failure (p<0.01). N-terminal pro-brain natriuretic peptide and left ventricular end-diastolic dimension were positively correlated with plasma N-terminal connective tissue growth factor levels (r=0.364, p=0.006; r=0.308, p=0.016), whereas there was a negative correlation between left ventricular ejection fraction and plasma N-terminal connective tissue growth factor (r=−0.353, p=0.005). Connective tissue growth factor was significantly correlated with the severity of heart failure (p<0.001). Moreover, addition of connective tissue growth factor to N-terminal pro-brain natriuretic peptide did not significantly increase area under curve for diagnosing heart failure (area under curve difference 0.031, p>0.05), but it obviously improved the ability of diagnosing heart failure in children, as demonstrated by the integrated discrimination improvement (6.2%, p=0.013) and net re-classification improvement (13.2%, p=0.017) indices.
Plasma N-terminal connective tissue growth factor is a promising diagnostic biomarker for heart failure in children.
SG-III laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%. We review the laser system and introduce the SG-III laser performance here.
Stable carbon isotope (δ13C) values of organic matter in lacustrine sediments are commonly used to trace past changes in terrestrial and aquatic carbon cycles. Here we use a high-resolution, well-dated δ13C record from Lake Tengchongqinghai (TCQH) in southwestern China, together with other proxy indices, to reconstruct the paleolimnological history over the past 18.5 ka. Organic matter in the sediments of Lake TCQH is derived predominately from aquatic macrophytes. The lacustrine primary productivity is closely linked with lake-level changes affected by variations in the strength of the Asian summer monsoon and modified by evapotranspiration. Similar to lake sediments world-wide, a ca. − 3‰ shift occurred in the δ13C values of Lake TCQH in response to the significant increase in atmospheric CO2 concentration during the last deglaciation. In the Holocene, the availability of dissolved CO2 in the lake water of Lake TCQH was determined by variations in hydraulic energy: low water turbulence creates a thick, stagnant boundary layer around aquatic plants, which will restrict the rate of CO2 diffusion and result in more positive δ13C values of aquatic plants. In contrast, significant water turbulence dramatically reduces the boundary layer thickness leading to more negative δ13C values of aquatic plants.
The neck is an important part of the body that connects the head to the torso, supporting the weight and generating the movement of the head. In this paper, a cable-driven parallel platform with a pneumatic muscle active support (CPPPMS) is presented for imitating human necks, where cable actuators imitate neck muscles and a pneumatic muscle actuator imitates spinal muscles, respectively. Analyzing the stiffness of the mechanism is carried out based on screw theory, and this mechanism is optimized according to the stiffness characteristics. While taking the dynamics of the pneumatic muscle active support into consideration as well as the cable dynamics and the dynamics of the Up-platform, a dynamic modeling approach to the CPPPMS is established. In order to overcome the flexibility and uncertainties amid the dynamic model, a sliding mode controller is investigated for trajectory tracking, and the stability of the control system is verified by a Lyapunov function. Moreover, a PD controller is proposed for a comparative study. The results of the simulation indicate that the sliding mode controller is more effective than the PD controller for the CPPPMS, and the CPPPMS provides feasible performances for operations under the sliding mode control.
To evaluate the effects of defoliation on green forage performance and grain yield (GY) variation in barley, five barley genotypes were imposed on three levels of defoliation treatments over two consecutive growing seasons in this study. The results indicated that green forage yields were significantly improved by repeated defoliation. The traits of green forage quality, including the ratio of dry weight to fresh weight, crude ash and calcium content were improved, while crude protein and crude fat were reduced, and crude fiber and phosphorus contents appeared not to be influenced by repeated defoliation. Plant height (PH), GY and other yield components, grain number per spike and thousand kernel weight, were significantly reduced by defoliation over the two growing seasons, while internode length below spike was less affected. Reduction in spike length and the number of spikes per plant were identified in only one year. Correlation analysis revealed that only PH exhibited a positive correlation with GY. Effects of genotype, interaction between genotype and defoliation, and environments on changes of forage yield and quality and GY were also discussed. Our current work provides a feasible approach to select elite barley cultivars with optimal defoliation treatments for both forage and grain uses in barley breeding programme.