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Previous neuroimaging studies demonstrated that retinal detachment (RD) subjects were associated with abnormal spontaneous brain activities; however, whether the altered interhemispheric functional connectivity (FC) occurred in RD patients remains unknown. The current study tried to explore the alternations of interhemispheric FC of the whole brain in unilateral RD patients using the voxel-mirrored homotopic connectivity (VMHC) method and their connections to clinical features. Methods: We recruited 30 patients with RD (16 males and 14 females) and 30 healthy controls (HCs) (16 males and 14 females) whose age and sex were closely matched. All subjects underwent the rs-fMRI scans. The VMHC method was applied to directly assess the hemispheres’ functional interaction. The VMHC in these brain areas, which could be used as biomarkers to differentiate RD from HC, was identified by the receiver operating characteristic (ROC) curve analyses. The relations between these patients’ clinical features and their mean VMHC signal values in multiple brain regions were calculated by Pearson correlation analysis. Results: RD patients had significantly lower VMHC values than HCs in the bilateral occipital lobe (Brodmann areas, BA 18), bilateral superior temporal gyrus (BA 39), and bilateral cuneus (BA 19). Moreover, the mean VMHC signal values of the bilateral cuneus were in positive correlation with the duration of the RD (r = 0.446, P = 0.013). Conclusion: Our results provided an evidence of disturbed interhemispheric FC in the visual area occurred in RD patients, which might provide some useful information to understand the neural mechanism of RD patients with acute vision loss. Furthermore, the VMHC values might indicate the progress of the RD.
The evolution of fatigue performance and surface mechanical properties of AISI 304 stainless steel induced by the electropulsing-assisted ultrasonic surface rolling process (EP-USRP) was systematically investigated by integrating instrumented indentation, scanning electron microscopy with electron backscatter diffraction, and transmission electron microscopy. The results indicate that higher hardness, greater strength, finer ultra-refined grains, and higher residual compressive stress are formed within the strengthened layer compared with the original ultrasonic surface rolling process (USRP). EP-USRP with the optimized experimental parameters can produce a higher average rotating bending fatigue strength for AISI 304 stainless steel than USRP. Anomalously and noteworthily, all fatigue specimens treated by EP-USRP showed an incomplete fracture, revealing a higher reservation of safety in practical engineering applications. The further modified structure strengthening and stress strengthening induced by EP-USRP are likely the primary intrinsic reasons for the observed phenomena. Furthermore, the influence mechanism of EP-USRP was discussed scrupulously.
The Chinese Solar and Geophysical Data (CSGD) was first issued at the Beijing Astronomical Observatory, Chinese Academy of Sciences (now the headquarter of the National Astronomical Observatories, Chinese Academy of Sciences) in 1971, when China’s satellite-industry was booming. CSGD covers the observational data (observations of the sunspots, solar flares, solar radio bursts, ionospheric storm and geomagnetic storm) from a couple of domestic observatories and the forecast data. The compiler of CSGD still keeps the data exchange with other institutes worldwide. The type of the dataset includes texts, tables, figures and so on. Up to now, we have electronized all the historic archives, making them easily accessible to people who are interested in them.
A glacier system is regarded as the ensemble of many glaciers sharing the same region, influenced by a similar climate and organized by certain intrinsic laws. It can be either ‘sensitive’ or ‘steady’. On the basis of the structure of the glacier system and the nature of the equilibrium-line altitudes at the steady state, functional models of a glacier system responding to climate warming were established, using the Kotlyakov–Krenke equation relating annual glacier ablation and mean summer temperature and the glacier system’s median size. The modeling results under the climatic scenarios with a rate of temperature increase of 0.01, 0.03 and 0.05 K a-1 indicate that by the end of this century the glacial area of China will be reduced by –14%, –40%and –60% respectively. However, model results show distinct differences between the sensitive glacier system and the steady glacier system.
A robust marine radiocarbon (14C) reservoir correction (ΔR) is essential for calibrating 14C dates of marine mollusks and fish bones routinely found in archaeological sites as discarded food remains and bones of terrestrial animals (including humans) with an appreciable marine diet. New ΔR values are reported for the atoll archipelago of the Marshall Islands, eastern Micronesia. Atolls consist of biogenetic material—mostly coral and foraminifera—that can be directly dated for establishing sequences of atoll emergence and islet development. After sectioning and examination using scanning electron microscopy (SEM) to screen for sample diagenesis, 6 pristine branch coral samples were selected from the modern oceanside beach, 3 archaeological sites, and islet developmental facies from Ebon Atoll (4º34′N, 168º41′E). Each sample was analyzed by U-series and accelerator mass spectrometry (AMS) 14C showing no substantial temporal ΔR variations and yielding a weighted mean ΔR of 41±42 yr1 spanning ~500 yr before earliest human colonization (the period when islets first became habitable) through the entire 2000-yr occupation sequence. Reliable published ΔR values for Micronesia and Δ14C data for Palmyra Island, together with our results for Ebon Atoll, indicate that the Pacific North Equatorial Counter Current is almost stable for the past 2500 yr.
The present study examines the characteristics of clay minerals in shale gas reservoirs and their influence on reservoir properties based on X-ray diffraction and scanning electron microscopy. These analyses were combined with optical microscopy observations and core and well-log data to investigate the genesis, distribution characteristics, main controlling factors and pore features of clay minerals of the Lower Silurian Longmaxi Formation in the East Sichuan area, China. The clay mineral assemblage consists of illite + mixed-layer illite-smectite (I-S) + chlorite. This assemblage includes three sources of clay minerals: detrital, authigenic and diagenetic minerals. The lower section of the Longmaxi Formation in the Jiaoshiba area has sealing ability which resulted in abnormal high pressures during hydrocarbon generation which inhibited illitization. Therefore, an anomalous transformation sequence is present in which the mixed-layer I-S content increases with depth. This anomalous transformation sequence can be used to infer the existence of abnormal high pressures. The detrital components of the formation also affect the clay-minerals content indirectly, especially the abundance of K-feldspar. The transformation of mixed-layer I-S to illite is limited due to the limited availability of K+, which determines the extent of transformation. Three types of pores were observed in the shale reservoir rocks of the Longmaxi Formation: interparticle (interP) pores, intraparticle (intraP) pores and organic-matter pores. The clay-mineral content controls the development of intraP pores, which are dominated by pores within clay particles. For a given clay mineral content, smectite and mixed-layer I-S were more conducive to the development of shale-gas reservoirs than other clay minerals.
The metadynamic recrystallization (MDRX) behavior of a Nb–V microalloyed nonquenched and tempered steel was investigated by isothermal hot compression tests on Gleeble-1500 thermal-mechanical simulator. Compression tests were performed using double hit schedules at temperatures of 1273–1423 K, strain rates of 0.01–5 s−1, initial grain sizes of 92–149 μm and an inter-pass time of 0.5–10 s. The experimental results show that MDRX softening fraction increases with the increasing of deformation temperature, strain rate, and inter-pass time, while it decreases with the increasing of initial grain size. Based on the experimental results, the MDRX softening fraction kinetic model and recrystallized grain size model of the tested steel was established. Besides, using the above mathematic models, a finite element model was built to simulate the MDRX process of the tested steel. The simulation results show good agreement with the experimental ones, which indicates that finite element method is an effective approach to analyze the MDRX behavior and the established that mathematic models of the tested steel are reliable and accurate.
The first application of U-series dating and accelerator mass spectrometry (AMS) assay of Polynesian archaeological Pocillopora spp. branch corals for deriving a precise local marine reservoir correction (ΔR) is described. Known-age corals were selected that spanned the entire culture-historical sequence for the Hawaiian Islands, thus eliminating the problem of not having known-age dated samples that cover the period of direct relevance to prehistorians; in this case, about AD 700–1800. Dating coral samples from windward and leeward coastlines of Moloka'i Island, with different offshore conditions such as upwelling, currents, wind patterns, coastal topography, and straight or embayed shorelines, provides insights into possible variations of local conditions on the same island—something that has never been attempted. In this regard, there was no spatial variability in ΔR during the 17th century. We report a weighted average ΔR value for Moloka'i Island of 52 ± 25 yr using 12 pair-dated dedicatory branch corals from religious archaeological sites and demonstrate that there is no significant temporal variability in ΔR between about AD 700 to 1800. In combination with 4 selected previously published ΔR values based on pre-bomb known-age marine shells, a revised ΔR of 66 ± 54 yr is established for the Hawaiian Islands. However, future research should examine the archipelago-wide spatial variability in ΔR with the analysis of additional dated archaeological coral samples.
Autophagy process in Toxoplasma gondii plays a vital role in regulating parasite survival or death. Thus, once having an understanding of certain effects of autophagy on the transformation of tachyzoite to bradyzoite this will allow us to elucidate the function of autophagy during parasite development. Herein, we used three TgAtg proteins involved in Atg8 conjugation system, TgAtg3, TgAtg7 and TgAtg8 to evaluate the autophagy level in tachyzoite and bradyzoite of Toxoplasma in vitro based on Pru TgAtg7-HA transgenic strains. We showed that both TgAtg3 and TgAtg8 were expressed at a significantly lower level in bradyzoites than in tachyzoites. Importantly, the number of parasites containing fluorescence-labelled TgAtg8 puncta was significantly reduced in bradyzoites than in tachyzoites, suggesting that autophagy is downregulated in Toxoplasma bradyzoite in vitro. Moreover, after treatment with drugs, bradyzoite-specific gene BAG1 levels decreased significantly in rapamycin-treated bradyzoites and increased significantly in 3-MA-treated bradyzoites in comparison with control bradyzoites, indicating that Toxoplasma autophagy is involved in the transformation of tachyzoite to bradyzoite in vitro. Together, it is suggested that autophagy may serve as a potential strategy to regulate the transformation.
High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1 σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38 yr. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 cal yr BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.
The influence of LF refining slag composition on desulfurization and inclusion
modification was investigated through industrial experiments and thermodynamic analysis.
The results show that the sulfide capacity decreases with the decrease in
and (%CaO)/(%Al2O3) of the slag. The theoretical sulfur distributions agree
well with the analysis results when the sulfide capacity is calculated by Zhang’s model,
but the theoretical sulfur distributions are higher than the analysis results when the
sulfide capacity is calculated by the KTH model. During the LF refining process,
inclusions are transformed from Al2O3 inclusions into CaO-MgO-Al2O3 system inclusions. Higher slag
basicity results in higher CaO and MgO and lower Al2O3 content inclusions in molten
steel at the end of the LF process.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.
A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.
The aim of the present study was to evaluate the effects of lutein and lycopene supplementation on carotid artery intima–media thickness (CAIMT) in subjects with subclinical atherosclerosis. A total of 144 subjects aged 45–68 years were recruited from local communities. All the subjects were randomly assigned to receive 20 mg lutein/d (n 48), 20 mg lutein/d+20 mg lycopene/d (n 48) or placebo (n 48) for 12 months. CAIMT was measured using Doppler ultrasonography at baseline and after 12 months, and serum lutein and lycopene concentrations were determined using HPLC. Serum lutein concentrations increased significantly from 0·34 to 1·96 μmol/l in the lutein group (P< 0·001) and from 0·35 to 1·66 μmol/l in the combination group (P< 0·001). Similarly, serum lycopene concentrations increased significantly from 0·18 to 0·71 μmol/l in the combination group at month 12 (P< 0·001), whereas no significant change was observed in the placebo group. The mean values of CAIMT decreased significantly by 0·035 mm (P= 0·042) and 0·073 mm (P< 0·001) in the lutein and combination groups at month 12, respectively. The change in CAIMT was inversely associated with the increase in serum lutein concentrations (P< 0·05) in both the active treatment groups and with that in serum lycopene concentrations (β = − 0·342, P= 0·031) in the combination group. Lutein and lycopene supplementation significantly increased the serum concentrations of lutein and lycopene with a decrease in CAIMT being associated with both concentrations. In addition, the combination of lutein and lycopene supplementation was more effective than lutein alone for protection against the development of CAIMT in Chinese subjects with subclinical atherosclerosis, and further studies are needed to confirm whether synergistic effects of lutein and lycopene exist.
The discovery of c. 1.77 Ga A-type granite in the Tarim Craton (TC) provides the first evidence that supports an extensional event related to fragmentation of the Columbia supercontinent in the late Palaeoproterozoic. We present laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U–Pb ages, Lu–Hf isotopic data and the whole-rock geochemical and Nd isotopic data of A-type granites in the Dunhuang area in the SE Tarim Craton. Zircon U–Pb dating for three granite samples indicate that they were emplaced at c. 1.77 Ga. Zircons from these granites have εHf(t) values ranging from –5.9 to 8.7, corresponding to two-stage model ages of 1.9–2.7 Ga. These granites exhibit the following petrological geochemical characteristics that are typical of A-type granite: (a) high content of SiO2 and alkalis (i.e. high K2O + Na2O with K2O/Na2O > 1), enrichment of high-field-strength elements (HFSE) and rare Earth elements (REE) (except for Eu) and extreme depletion of Ba, Sr, P, Ti and Eu; (b) 10000×Ga/Al ratios in the Dunhuang granites of 3.5–4.4, with an average value of 3.79 which is similar to the global average of 3.75 for A-type granites; (c) the presence of characteristic minerals such as amphibole, sphene and perthite; and (d) zirconium saturation temperature results indicate that the Dunhuang granites have high initial magmatic temperatures in the range 887–950°C, similar to those of typical of A-type granites. Whole-rock εNd(t) values range from –2.5 to –6.2 and TDM model ages from 2.3 to 2.7 Ga. Nd–Hf isotopic and whole-rock geochemical data indicate that these granites were most likely derived from the late Archean crustal source in a post-collisional/post-orogenic extensional tectonic environment. The late Palaeoproterozoic A-type granites in the TC could be correlated with those of the North China Craton (NCC), India and the Canadian Shield, thus demonstrating extensional tectonics and break-up of the Columbia supercontinent.
Percutaneous transcatheter occlusion has benefited thousands of patients suffering from patent foramen ovale and atrial septal defect. However, no general agreement has been reached on the superiority among occluders. Thus, a meta-analysis between the two most commonly adopted types of occluders was conducted.
The literature review has identified relevant studies up to May, 2011 in the databases of PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and World Health Organization clinical trials registry centre. Meta-analysis was performed in a fixed/random effects model using Revman 5.1.1. Information on complications and outcomes was extracted.
Analysis from included studies reports an outcome in favour of the Amplatzer. The Amplatzer has proven its superiority in efficacy with a significantly lower risk of early (95% confidence interval = 0.09–0.34) and long-term (95% confidence interval = 0.14–0.97) residual shunt rate for atrial septal defect occlusion, although no significant difference in performance has been reported for patent foramen ovale. In addition, the Amplatzer has also remarkably reduced the risk of embolisation by the device (95% confidence interval = 0.07–0.45) for atrial septal defect and new-set atrial fibrillation (95% confidence interval = 0.18–0.48) for patent foramen ovale. On evaluation of recurrent thrombotic events, it was found that the Amplatzer greatly lowered the rate of thrombus formation on the device (95% confidence interval = 0.02–0.21) for patent foramen ovale; however, no statistical difference was found on atrial septal defect evaluation. However, the result indicated no statistically significant difference between the two kinds of occluders in stroke and transient ischaemic attack of patent foramen ovale.
The meta-analysis has proven the Amplatzer to be the superior occluder, serving better prognosis with more fluent procedure and less complications.
Observations of the interplanetary shock provide us with strong evidences of particle acceleration to multi-MeV protons in a coronal mass ejection (CME). Diffusive shock acceleration (DSA) is an efficient mechanism for cosmic ray (CR). This work presents a dynamical Monte Carlo simulation of a CME-driven shock on 14-Dec-2006 by using a series of Gaussian scattering angular distributions. With the simulated results, we find that particle energy spectrum is affected by energy injection processes under the anisotropic scattering law.
Ultrashort electron bunch trains can be used for plasma wake field acceleration (PWFA) to overcome the limit of transformer ratio of a single electron bunch, or high-power terahertz (Thz) radiation production by various radiation mechanisms. Basic facility for high-power THz radiation development based on ultrashort electron beam has been set up at accelerator lab of TUB. Using birefringent crystal serials, ultraviolet (UV) pulse shaping for photocathode radio frequency gun to produce THz-repetition-rate pulse train was realized. Driven by such pulses, ultrashort electron bunch train with picosecond (ps) spacing was obtained for THz production. Measurement of the stacked UV pulse trains was done by difference frequency generation (DFG), and the measured group velocity mismatch of α-BBO crystal at 266.7-nm wavelength was 0.8 ps/mm. This method may also be applied to form ramped electron bunch trains for PWFA.