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Geochronological, major and trace element, and Sr–Nd–Hf isotopic data are reported for the monzonitic rocks of the Fushan pluton in the Taihang Mountains, central North China Craton, in order to investigate their sources, petrogenesis and tectonic implications. Zircon U–Pb dating results reveal that the Fushan pluton was emplaced during the Early Cretaceous (∼126–124 Ma). The monzonites and quartz monzonites are mainly characterized by calc-alkaline and magnesian features and display light rare earth element (LREE) enrichment and flat heavy REE (HREE) patterns with slightly positive Eu anomalies. They have similar whole-rock initial 87Sr/86Sr ratios (0.70653–0.70819), εNd(t) values (−13.6 to −18.6) and zircon εHf(t) values (−21.8 to −17.3). The primary magma of the Fushan pluton was derived from the partial melting of a spinel-facies amphibole-bearing ancient enriched lithospheric mantle. The monzonitic rocks also have high Ba–Sr and low Y and Yb contents, with high Sr/Y and La/Yb ratios. These geochemical features of monzonitic rocks are not only inherited from the magma source but also significantly enhanced by crystal fractionation during magmatic evolution; e.g. hornblende fractionation increased the Ba–Sr concentrations and Sr/Y ratios. During the Early Cretaceous, the slab sinking and roll-back of the Palaeo-Pacific Plate could have created an ancient big mantle wedge beneath East Asia and induced a lithospheric extensional process in the central North China Craton within an intracontinental setting.
Good canopy structure is essential for optimal maize (Zea mays L.) production. However, creating appropriate maize canopy structure can be difficult, because the characteristics of individual plants are altered by changes in plant age, density and interactions with neighbouring plants. The objective of the current study was to find a reliable method for building good maize canopy structure by analysing changes in canopy structure, light distribution and grain yield (GY). A modern maize cultivar (ZhengDan958) was planted at 12 densities ranging from 1.5 to 18 plants/m2 at two field locations in Xinjiang, China. At the silking stage (R1), plant and ear height increased with plant density as well as leaf area index (LAI), whereas leaf area per plant decreased logarithmically. The fraction of light intercepted by the plant (F) increased with increasing plant density, but the light extinction coefficient (K) decreased linearly from 0.61 to 0.39. Taking the optimum value of F (95%) as an example, and using measured values of K for each plant density at R1 and the equation from Beer's law, the corresponding (theoretical) LAI for each plant density was calculated and optimum plant density (9.72 plants/m2) obtained by calculating the difference between theoretical LAIs and actual observations. Further analysis showed that plant density ranging from 10.64 to 11.55 plants/m2 yielded a stable GY range. Therefore, taking into account the persistence time for maximum LAI, the plant density required to obtain an ideal GY maize canopy structure should be increased by 10–18% from 9.72 plants/m2.
Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid β-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid β-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.
There is an ongoing relationship between host plants and herbivores. The nutrient substances and secondary compounds found in the host plant can not only impact the growth and development process of herbivores, but, more importantly, may also affect their survival and reproductive fitness. Vitellogenesis is the core process of reproductive regulation and is generally considered as a reliable indicator for evaluating the degree of ovarian development in females. Vitellogenin (Vg) plays a critical role in the synthesis and secretion of yolk protein. In this study, the full-length cDNA of the Vg gene in an alien invasive species, the nipa palm hispid beetle Octodonta nipae Maulik (Coleoptera: Chrysomelidae) (OnVg) was cloned and, the effect of host plant on the OnVg expression level and ovarian development was investigated. The results revealed that the OnVg was highly and exclusively expressed in adult females, but barely detectable in larvae, pupae and adult males. The relative expression level of OnVg and egg hatchability were much higher in females fed on Phoenix canariensis (their preferred host) than those fed on Phoenix roebelenii. A positive correlation relationship between OnVg expression and egg hatchability was also detected. Additionally, the anatomy of the female reproductive system showed that the ovaries of individuals fed on P. canariensis were considerably more developed than in females fed on P. roebelenii. The results may be applicable to many pest management situations through reproductive disturbance by alternating host plant species or varieties or by reproductive regulation through vitellogenesis mediated by specific endocrine hormones.
The long-lived radioisotope 59Ni is of interest in various research fields including neutron dosimetry, radioactive waste management, and astrophysics. In order to achieve the sensitivity required for such applications, the technique of accelerator mass spectrometry (AMS) 59Ni measurement has been developed at the AMS facility at China Institute of Atomic Energy (CIAE). Based on the AE-Q3D detection system in the CIAE AMS facility, the interference in 59Ni counting from the isobar 59Co has been reduced by a factor of 8 × 106. A series of laboratory reference samples and a blank sample were measured to check the performance of 59Ni measurement. A detection sensitivity of about 5 × 10−13 (59Ni/Ni) has been obtained.
We present experimental evidence that a minute amount of polymer additives can significantly enhance heat transport in the bulk region of turbulent thermal convection. The effects of polymer additives are found to be the enhancement of coherent heat fluxes and suppression of incoherent heat fluxes. The enhanced heat transport is associated with the increased coherency of thermal plumes, as a result of the suppression of small-scale turbulent fluctuations by polymers. The incoherent heat flux, arising from turbulent background fluctuations, makes no net contribution to heat transport. The fact that polymer additives can increase the coherency of thermal plumes is supported by the measurements of a number of local quantities, such as the extracted plume amplitude and width, the velocity autocorrelation functions and the velocity–temperature cross-correlation coefficient. The results from local measurements also suggest the existence of a threshold value for the polymer concentration, only above which significant modification of the plume coherent properties and enhancement of the local heat flux can be observed. Estimation of the plume emission rate suggests a stabilization of the thermal boundary layer by polymer additives.
Charged particle diagnostics is one of the required techniques for implosion areal density diagnostics at the SG-III facility. Several proton spectrometers are under development, and some preliminary areal density diagnostics have been carried out. The response of the key detector, CR39, to charged particles was investigated in detail. A new track profile simulation code based on a semi-empirical model was developed. The energy response of the CR39 detector was calibrated with the accelerator protons and alphas from a 241Am source. A proton spectrometer based on the filtered CR39 detector was developed, and D–D primary proton measurements were implemented. A step range filter spectrometer was developed, and preliminary areal density diagnostics was carried out. A wedged range filter spectrometer array made of Si with a higher resolution was designed and developed at the SG-III facility. A particle response simulation code by the Monte Carlo method and a spectra unfolding code were developed. The capability was evaluated in detail by simulations.
In current transparent Si based photovoltaic (PV) module fabrication, green or infrared laser is the most common used band frequency to wipe off the silicon and back contact layer in perpendicular direction of cells. However, this method would result in more power loss than calculation value due to the side effects during the process such as constructional damage of module and shunt effect. A new method is presented here which focus on wiping off more silicon layer by employing green pulsed laser(532 nm wavelength) along the parallel direction of Pattern2, and it shows higher efficiency and more attractive appearance.
The role of oxidative stress in skeletal health is unclear. The present study investigated whether a high dietary intake of antioxidant nutrients (vitamins C and E, β-carotene, animal-derived vitamin A, retinol equivalents, Zn and Se) is associated with a reduced risk of hip fracture in elderly Chinese. This 1:1 matched case–control study involved 726 elderly Chinese with hip fracture and 726 control subjects, recruited between June 2009 and May 2013. Face-to-face interviews were conducted to determine habitual dietary intakes of the above-mentioned seven nutrients based on a seventy-nine-item FFQ and information on various covariates, and an antioxidant score was calculated. After adjustment for potential covariates, dose-dependent inverse associations were observed between the dietary intake of vitamin C, vitamin E, β-carotene, and Se and antioxidant score and the risk of hip fracture (P for trend ≤ 0·005). The OR of hip fracture for the highest (v. lowest) quartile of intake were 0·39 (95 % CI 0·28, 0·56) for vitamin C, 0·23 (95 % CI 0·16, 0·33) for vitamin E, 0·51 (95 % CI 0·36, 0·73) for β-carotene, 0·43 (95 % CI 0·26, 0·70) for Se and 0·24 (95 % CI 0·17, 0·36) for the antioxidant score. A moderate-to-high dietary intake of retinol equivalents in quartiles 2–4 (v. 1) was found to be associated with a lower risk of hip fracture (OR range: 0·51–0·63, P< 0·05). No significant association was observed between dietary Zn or animal-derived vitamin A intake and hip fracture risk (P for trend >0·20). In conclusion, a higher dietary intake of vitamins C and E, β-carotene, and Se and a moderate-to-high dietary intake of retinol equivalents are associated with a lower risk of hip fracture in elderly Chinese.
An ion beam has the unique feature of being able to deposit its main energy inside a human body to kill cancer cells or inside material. However, conventional ion accelerators tend to be huge in size and cost. In this paper, a future intense-laser ion accelerator is discussed to make the laser-based ion accelerator compact and controllable. The issues in the laser ion accelerator include the energy efficiency from the laser to the ions, the ion beam collimation, the ion energy spectrum control, the ion beam bunching, and the ion particle energy control. In the study, each component is designed to control the ion beam quality by particle simulations. The energy efficiency from the laser to ions is improved by using a solid target with a fine sub-wavelength structure or a near-critical-density gas plasma. The ion beam collimation is performed by holes behind the solid target or a multi-layered solid target. The control of the ion energy spectrum and the ion particle energy, and the ion beam bunching are successfully realized by a multi-stage laser–target interaction.
The present study investigated the effects of xanthophyll supplementation on production performance, antioxidant capacity (measured by glutathione peroxidase, superoxide dismutase (SOD), catalase, total antioxidant capacity (T-AOC), and reduced glutathione:oxidised glutathione ratio (GSH:GSSG)) and lipid peroxidation (measured by malondialdehyde (MDA)) in breeding hens and chicks. In Expt 1, 432 hens were fed diets supplemented with 0 (control group), 20 or 40 mg xanthophyll/kg diet. Blood samples were taken at 7, 14, 21, 28 and 35 d of the trial. Liver and jejunal mucosa were sampled at 35 d. Both xanthophyll groups improved serum SOD at 21 and 28 d, serum T-AOC at 21 d and liver T-AOC, and serum GSH:GSSG at 21, 28 and 35 d and liver GSH:GSSG. Xanthophylls also decreased serum MDA at 21 d in hens. Expt 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg in ovo xanthophyll/kg diet of hens were fed a diet containing either 0 or 40 mg xanthophyll/kg diet. Liver samples were collected at 0, 7, 14 and 21 d after hatching. Blood samples were also collected at 21 d. In ovo-deposited xanthophylls increased antioxidant capacity and decreased MDA in the liver mainly within 1 week after hatching. Maternal effects gradually vanished during 1–2 weeks after hatching. Dietary xanthophylls increased antioxidant capacity and decreased MDA in the liver and serum mainly from 2 weeks onwards. Data suggested that xanthophyll supplementation enhanced antioxidant capacity and reduced lipid peroxidation in different tissues of hens and chicks.
Cu–In–Ga precursor thin films were deposited onto soda lime glass by magnetron cosputtering CuIn and CuGa alloy targets. After that, Cu(In,Ga)Se2(CIGSe) absorbers were formed by selenizing those alloy precursors with Se vapor at 550 °C. The influence of the precursor temperature on the properties of CIGSe thin film was investigated. The results show that a lot of pinholes existed in the CIGSe thin film produced by selenizing the Cu–In–Ga alloy precursor, which was sputtering deposited at ambient temperature. After sputtering substrate temperature of 250 °C was applied, pinholes were avoided. The surface roughness of Cu–In–Ga precursor increased with the increase of sputtering substrate temperature. Due to the volume expansion of selenization process, even the precursor with high surface roughness could be converted to smooth and compact CIGSe thin film.
The growth of silicon nanotubes (SiNTs) by a dual-RF-plasma treatment technique is reported here. These SiNTs are vertically aligned and self-assembled from Si substrates at 500 degree Celsius by the use of Cu catalysts. Their diameters are ∼50 to 80 nm with tubular wall thickness of ∼10-15nm. Cu vapors were found partially filled inside the SiNTs. This is a novel technique that can convert bulk materials into their nanostructures.
We report on microwave measurements of complex permittivity of single-walled carbon nanotubes (SWNTs). The SWNT samples are a mixture of semiconducting and metallic nanotubes suspended using Pluronic (F108) as a stabilizing surfactant agent. Other samples that were characterized include pluronic powder and an oriented carpet of multi-walled nanotubes (MWNT). For broadband measurements, the shielded open-circuited transmission line technique was used. Single frequency (resonant) measurements for liquid-based SWNT samples were carried out by employing two different modes in specially designed microwave dielectric resonators (DR), either with a cylindrical hole in the center of a dielectric disk or with a horizontal gap (split resonator). The first resonator can operate in either TE011 or TM011 modes (3.4 GHz and 6 GHz) and was designed for liquid or powder characterization. For pluronic suspended SWNT, real (epsilon) and imaginary parts of permittivity were found at 3.4 GHz as 3.5 and 0.72, respectively.
Ferroelectric random access memory (FeRAM) is believed to be the most promising candidate for the next generation non-volatile memory due to its fast access time and low power consumption. Fabrication technologies of FeRAM can be divided into two parts: CMOS technologies for circuits which are standard and can be shared with traditional IC process line, and process relating to ferroelectric which is separated with CMOS process and defined as backend module. This paper described technologies for integrating ferroelectric capacitors into standard CMOS, mainly about modeling of ferroelectric capacitors and backend fabrication technologies. Hysteresis loop of the ferroelectric capacitor is the basis for FeRAM to store data. Models to describe this characteristic are the key for the design of FeRAM. A transient behavioral ferroelectric capacitor model based on C-V relation for circuit simulation is developed. The arc tangent function is used to describe the hysteresis loop. “Negative capacitance” phenomenon at reversing points of applied voltage is analyzed and introduced to the model to describe transient behaviors of the capacitor. Compact equivalent circuits are introduced to integrate this model into HSPICE for circuit simulation. Ferroelectric materials fabrication, electrodes integration and etching are the main technologies of FeRAM fabrication process. An metal organic chemical vapor deposition (MOCVD) process is developed to fabricate high quality Pb(Zr1-xTix)O3 (PZT) films. Pt is known to cause the fatigue problems when used as electrodes with PZT. Ir is used as electrodes to improve the fatigue property of PZT based capacitors, and mechanism of the fatigue is analyzed. Hard mask is used to reduce the size of the capacitors and damage caused in etching process. In our process, Al2O3 is developed as hard mask, which simplifies the FeRAM backend integration process.
For the first time, patterned growth of boron nitride nanotubes (BNNTs) on Si substrates has been achieved by catalytic chemical vapor deposition (CCVD). Following the boron oxide chemical pathway and our growth vapor trapping approach, high quality and quantity BNNTs can be produced. Effective catalysts have been found to facilitate the growth of BNNTs, while some critical parameters of the synthesis have also been identified to control the quality and density. The success of patterned growth of high quality BNNTs not only explains the roles of the effective catalysts during the synthesis process, but could also be of technologically important for future device fabrication.
We developed a BioMEMS device to study cell- mitochondrial physiological functionalities. The pathogenesis of many diseases including obesity, diabetes, heart failure as well as aging has been linked to functional defects of mitochondria. This is understandable as the mitochondria produces up to 90% of ATP, and plays a critical role in cell signaling and apoptosis. The synthesis of ATP is determined by the electrical potential across the inner mitochondrial membrane (IMM) and by the pH difference due to proton flux across it. Therefore, electrical characterization by E-fields with complementary chemical testing was used here. Mitochondrial ion channels present in the IMM control specific ion fluxes, and maintain ion homeostasis, matrix volume, IMM potential etc and thus serve a central role in cell growth and death related processes. Defects in ion channels (Channelopathies) are being attributed to many diseases like cancer, neurodegeneration, etc. Complete physiological roles of various ion channels and their interactions are still unknown, hindering the development of targeted therapeutic agents. The BioMEMS device was fabricated as an SU-8 based microfluidic system with gold electrodes on SiO2/Si wafers for electromagnetic interrogation. Ion Sensitive Field Effect Transistors (ISFETs) were incorporated for proton studies important in electron transport chain, together with monitoring Na+, K+, Ca++ions for ion channel studies. ISFETs are chemically sensitive MOSFET devices, their threshold voltage is directly proportional to the electrolytic H+ ion variation. These ISFETs (sensitivity ˜55 mV/pH for H+) were further realized as specific ion sensitive CHEMFETs by depositing a poly-HEMA layer sandwiched between the gate and a final specific ion sensitive membrane. Electrodes for dielectric spectroscopy studies of mitochondria were designed as 2- and 4-probe structures for optimized operation over a wide frequency range. In addition, to limit polarization effects (which masks actual impedance for high conductivity solutions at low frequencies), a 4-electrode set-up with unique meshed pickup electrodes (7.5×7.5 μm2 loops with 4 μm wires) was fabricated. An electrical model was developed for the mitochondrial sample, and its frequency response correlated with impedance spectroscopy experiments of sarcolemmal mitochondria. Using the mesh electrode structure, we obtained a reduction of 83.28% in impedance at 200 Hz. COMSOL simulations of selected electrical structures in this sensor were compared with experimental results to better understand the physical system. The simultaneous measurement of membrane potential, ion concentrations and pH would enhance diagnostics and studies of mitochondrial diseases.
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.