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In this paper, effects of discharge parameters and modulation frequency on the signal of laser-induced fluorescence measurements of ion velocity distribution functions are investigated in the LIF Test Source. A maximum modulation frequency is found for each given set of parameters, beyond which the signal gradually declines. Meanwhile, this maximum modulation frequency occurred consistently at ~1/10 of the theoretical frequency limit and photon counts received by a photomultiplier tube, which indicates that as modulation frequency and the associated per-pulse-excitation-event count decrease, the transition from the macroscopic statistical signal to the microscopic probabilistic signal is a gradual process.
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.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
Remote-sensing and GIS techniques in conjunction with field investigations show how glacier mass loss has led to the rapid growth of Linggo Co, a glacier-fed lake on the central Tibetan Plateau, which has expanded by 21.3% in area between 1974 and 2010, with a lake-level rise of ˜11.2m. The lake volume of Linggo Co increased at a rate of 0.02 × 106, 42.67 × 106 and 65.8 × I06m3a-1 during the periods 1974-92, 1992-99 and 1999-2010, respectively. Other nonglacier-fed lakes in the vicinity (i.e. Longwei Co, Amur Co and Darngo Co Ngion) shrank considerably from the early 1970s to 1992 and then expanded from 1992 to 2010. Despite being in the same climate region, Linggo Co and the non-glacier-fed lakes have differed in response to climate change. The glaciers in the catchment of Linggo Co retreated by 2.4% in area between 1974 and 2007, and their mean thickness decreased by 6.19 ± 1.91 m between 1974 and 2000, with an associated glacier meltwater runoff of (7.52 ± 2.32) × 108 m3. The results indicate that glacier mass loss had a significant impact on the growth of Linggo Co over the past 40 years.
Using in-situ measured data from Qiyi Glacier, in combination with meteorological and run-off data from stations, a distributed degree-day model was developed for 631 investigated glaciers in the Beida River catchment to explore glacier mass change and its effect on streamflow. The results showed that the average mass balance was −272 ± 67 mm w.e. a−1, with an ice loss of 3.99 Gt during 1957–2013. Assuming a continuous linear trend, equilibrium line altitude rose by 242 m. Compared with morpho-topographic variables, climatic control is a more important factor affecting glacier change. Mass-balance sensitivity to air temperature was −239 mm w.e.°C−1 a−1, while to precipitation it was +1.1 mm w.e. mm−1 a−1. That is, a 210 mm increase in precipitation would be needed to compensate for the net mass loss induced by an air temperature increase of 1°C. Average annual glacier meltwater runoff was 1.51 × 108 m3 from 1957 to 2013, accounting for 15.2% of surface runoff. The time series of meltwater runoff changed abruptly in 2000, and its contribution to surface runoff increased from 13.9 to 20.4%.
Cerebral small vessel disease (SVD) is the common cause of cognitive decline in the old population. MRI can be used to clarify its mechanisms. However, the surrogate markers of MRI for early cognitive impairment in SVD remain uncertain to date. We investigated the cognitive impacts of cerebral microbleeds (CMBs), diffusion tensor imaging (DTI), and brain volumetric measurements in a cohort of post-stroke non-dementia SVD patients.
Methods:
Fifty five non-dementia SVD patients were consecutively recruited and categorized into two groups as no cognitive impairment (NCI) (n = 23) or vascular mild cognitive impairment (VaMCI) (n = 32). Detailed neuropsychological assessment and multimodal MRI were completed.
Results:
The two groups differed significantly on Z scores of all cognitive domains (all p < 0.01) except for the language. There were more patients with hypertension (p = 0.038) or depression (p = 0.019) in the VaMCI than those in the NCI group. Multiple regression analysis of cognition showed periventricular mean diffusivity (MD) (β = −0.457, p < 0.01) and deep CMBs numbers (β = −0.352, p < 0.01) as the predictors of attention/executive function, which explained 45.2% of the total variance. Periventricular MD was the independent predictor for either memory (β = −0.314, p < 0.05) or visuo-spatial function (β = −0.375, p < 0.01); however, only small proportion of variance could be accounted for (9.8% and 12.4%, respectively). Language was not found to be correlated with any of the MRI parameters. No correlation was found between brain atrophic indices and any of the cognitive measures.
Conclusion:
Arteriosclerotic CMBs and periventricular white matter disintegrity seem to be independent MRI surrogated markers in the early stage of cognitive impairment in SVD.
Hypoxia is the primary stimulus for the production of erythropoietin (EPO) in both fetal and adult life. Here, we investigated fetal plasma EPO concentrations in monochorionic (MC) twin pregnancies with selective intrauterine growth restriction (sIUGR) and abnormal umbilical artery (UA) Doppler. We diagnosed sIUGR in presence of (1) birth-weight discordance >20% and (2) either twin with a birth weight <10th percentile. An abnormal UA Doppler was defined as a persistent absent-reverse end diastolic flow (AREDF). The intertwin EPO ratio was calculated as the plasma EPO level of the smaller (or small-for-gestational-age) twin divided by the EPO concentration of the larger (or appropriate-for-gestational-age (AGA)) twin. Thirty-two MC twin pairs were included. Of these, 17 pairs were normal twins (Group 1), seven pairs were twins with sIUGR without UA Doppler abnormalities (Group 2), and eight pairs were twins with sIUGR and UA Doppler abnormalities (Group 3). The highest EPO ratio was identified in Group 3 (p < .001) but no significant differences were observed between Groups 1 and 2. Fetal hemoglobin levels did not differ significantly in the three groups, and fetal EPO concentration did not correlate with gestational age at birth. We conclude that fetal plasma EPO concentrations are selectively increased in MC twin pregnancies with sIUGR and abnormal UA Doppler, possibly as a result of uncompensated hypoxia.
Proton radiography is used for advanced hydrotesting as a new type radiography technology due to its powerful penetration capability and high detection efficiency. A new proton radiography terminal will be developed to radiograph static samples at the Institute of Modern Physics of Chinese Academy of Science. The proton beam with the maximum energy of 2.6 GeV will be produced by Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring. The proton radiography terminal consists of the matching magnetic lens and the Zumbro lens system. In this paper, the design scheme and all optic parameters of this beam terminal for 2.6 GeV proton energy are presented by simulating the beam optics using WINAGILE code. My-BOC code is used to test the particle tracking of proton radiography beam line. Geant4 and G4beamline codes are used for simulating the proton radiography system. The results show that the transmission efficiency of proton without target is 100%, and the effect of secondary particles can be neglected. To test this proton radiography system, the proton images for an aluminum plate sample with two rectangular orifices and a step brass plate sample are respectively simulated using Geant4 code. The results show that the best spatial resolution is about 36 μm, and the differences of the thickness are not >10%.
Drynaria fortunei (Kunze) J. Sm. (DF), a Chinese herb commonly used for the treatment of bone fracture, was previously shown to exert anabolic effects on bone. However, its active ingredients as well as the mechanisms of action are far from clear. The present study aimed to characterise the bone anabolic effects of DF flavonoid fraction (DFTF) in ovariectomised (OVX) mice and to determine if DFTF and its isolated compounds exert oestrogen-like effects in rat osteoblast-like UMR-106 cells. Young OVX C57/BL6J mice were treated orally with DFTF (0·087, 0·173 or 0·346 mg/g per d), 17β-oestradiol (2 μg/g per d) or its vehicle for 6 weeks. Serum and urine samples were collected for biochemical marker analysis. Bones were collected for computed tomography analysis. UMR-106 cells were treated with DFTF and isolated compounds naringin, (2S)-5,7,3′,5′-tetrahydroxy-flavonone 7-O-neohesperidoside (compound 1) and 5,7-dihydroxychromone 7-O-neohesperidoside (compound 2). DFTF exerted dose-dependent effects in improving bone mineral densities as well as bone strength at the femur, tibia and lumbar spine L1 in OVX mice. DFTF and the three isolated compounds stimulated osteoblastic cell proliferation and alkaline phosphatase activities in a dose-dependent manner. In addition, they stimulated the ratio of osteoprotegrin and receptor-activator NF-κB ligand mRNA expression, suggesting their involvement in inhibiting osteoclastogenesis. These stimulatory effects on osteoblastic functions were abolished in the presence of oestrogen receptor (ER) antagonist, ICI 182780. The present results suggested that DFTF is effective in protecting against OVX-induced bone loss in mice, and its actions in regulating osteoblastic activities appear to be mediated by ER.
Flavonoids are the active components of Herba epimedii (HEP), a commonly used herb for the management of osteoporosis in China over the centuries. The present study aims to characterise the in vivo effects of its total flavonoid (TF) fraction on bone properties and mineral metabolism as well as to study the mechanism involved in achieving its protective effects against ovariectomy (OVX)-induced bone loss. TF suppressed OVX-induced increase in urinary Ca excretion as well as loss of bone mass and strength at the distal femur in mice in a dose-dependent manner. The changes in urinary Ca excretion were inversely correlated with the expressions of renal Ca transport protein (CaBP-28K) and vitamin D receptor mRNA in OVX mice. TF (100 μg/g) treatment prevented the deterioration of trabecular bone microarchitecture induced by OVX in mice. In addition, TF treatment increased the expression of type I collagen and osteocalcin mRNA and the ratio of osteoprotegerin/receptor activator of NF-κB ligand mRNA, and suppressed the increase in IL-6 mRNA induced by OVX in the femur of mice. The present results indicate that the optimal dosage of the TF fraction of HEP for the improvement of bone properties and mineral metabolism in OVX mice was between 50 and 100 μg/g. Mechanistic studies indicated that TF might increase renal Ca reabsorption, stimulate the process of osteoblast formation as well as suppress the process of osteoclastogenesis in OVX mice.
22q11.2 microdeletion is the most common microdeletion in the global population. Congenital cardiac disease is the most frequently observed feature of this syndrome. The prognosis of patients with 22q11.2 copy number aberrations varies from those without 22q11.2 deletion or duplication.
Methods
We enrolled 241 patients from Nanjing Drum Tower Hospital and Nanjing Sick Children’s Hospital, 227 being scheduled for cardiac surgery, and 14 cases being fetuses aged from 24 to 36 gestational weeks. We performed karyotypic analysis and multiplex ligation-dependent probe amplification in all cases.
Results
Karyotypic analysis demonstrated 3 cases with trisomy 21, and 1 case with mosaic trisomy 8 [47,XY,+8/46,XY(1:2)]. Multiplex ligation-dependent probe amplification analysis revealed 10 cases (4.15%) with changes in the number of copies within the region of 22q11.2, of which 7 cases were hemizygous interstitial microdeletion from CLTCL1 to LZTR1, 1 case with deletion of the region from CLTCL1 to PCQAP, and 2 cases with 22q11.2 duplication, one of which spanned from ZNF74 to LZTR1, and simultaneously showed trisomy 21 by karyotyping analysis, and the other spanned from HIC2 to TOP3B. The phenotypes of the cardiac lesions included 3 cases of ventricular septal defect, 3 of tetralogy of Fallot, 2 of combined ventricular and atrial septal defects, and 2 with pulmonary arterial stenosis.
Conclusions
Patients with congenitally malformed hearts who are scheduled for cardiac surgery, as well as fetuses with congenital cardiac disease, should routinely undergo karyotypic analysis and examination for 22q11.2 aberrations. Multiplex ligation-dependent probe amplification has been proven to be a cost-effective diagnostic technique for 22q11 deletion syndrome.
A method of absolutely unfolding the atomic spectrum by a pinhole transmission grating spectrometer (TGS) is discussed in detail. The numerical process considers both the factors of higher-dispersive-order overlapping of TGS and source-size widening effects. Real soft-X-ray spectra of aluminum, copper, and gold plasmas are presented of experiments performed on the Six-Beam Laser Facility at the Shanghai Institute of Optics and Fine Mechanics.
A fluorescence switch by the photoisomerization of a photochromic compound in CH3CN and in a polymer film using a bistable photochromic (1,2-bis(2-methylbenzo[b]thiophen-3-yl) hexafluorocyclopentene) (BTF6) and a fluorescent 3-(2-benzothiazolyl)-7-(diethylamino) coumarin (coumarin6) was demonstrated. Because only the closed form of BTF6 serves as a fluorescence quencher of coumarin6, and the read (406 nm), write (254 nm), and erase (>500 nm) wavelengths are well-separated, a reversible modulation of the fluorescence of coumarin6 with high contrast and high sensitivity is expected to be realized. This system may represent an alternative to the fluorescence switches that are based on covalent systems in the potentially long-term optical data or image storage schemes utilizing luminescence intensity readout.
This study aimed to evaluate the hypocholesterolaemic property of milk-kefir and soyamilk-kefir. Male hamsters were fed on a cholesterol-free or cholesterol-enriched diet containing 10% skimmed milk, milk-kefir, soyamilk or soyamilk-kefir for a period of 8 weeks. The soyamilk, milk-kefir and soyamilk-kefir diets all tended towards a lowering of serum triacylglycerol and total cholesterol concentrations, and a reduction of cholesterol accumulation in the liver, the decrease in serum cholesterol concentration being mainly in the non-HDL fraction. The soyamilk-kefir diet led to a significant increase in the faecal excretion of neutral sterols and bile acids compared with the other two diets. The soyamilk-kefir diet also elicited a significant decrease in the serum ratio of non-HDL-cholesterol to HDL-cholesterol, compared with the control, than was the case for the other diets. These findings demonstrate that soyamilk-kefir may be considered to be among the more promising food components in terms of preventing CVD through its hypocholesterolaemic action.
The Laplacians form a class of the most important differential operators in white noise analysis. The goal of this paper is to give their characterizations. Our main tools are the Fock expansions of operators in terms of integral kernel operators and rotation-invariance. In Section 1, the fundamental setting of white noise analysis is introduced briefly. In Section 2, integral kernel operators and the Fock expansions of operators are given. The characterization theorems for number operator, Gross-Laplacian and Euler operator are given in Sections 3, 4 and 5 respectively.
We will define local times of self-intersection for multidimensional Brownian motion as generalized Wiener functionals under the framework of white noise analysis as in H. Watanabe ([6]). By making use of the chaotic representation of -function and precise computation we get a deep insight into the problem. In the section 1 multiple Wiener integrals with respect to multidimensional Brownian motion and chaotic representations for square-integrable Wiener functionals are given. They are indispensable, but seem not to be formulated clearly and correctly before. The useful concepts and results of white noise analysis are illustrated in the section 2. Section 3 is the main part of the paper. The applications to local times are introduced in the section 4 briefly.
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