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A 230Th/U-dated stalagmite from Hulu Cave was analyzed for δ18O, δ13C, and trace elements. A ~10-yr-resolution δ18O record, spanning 51.7–42.6 ka, revealed Dansgaard-Oeschger (DO) events 14 to 11. A similar rapid transition and synchronous timing of the onset of DO 12 is evident between the Greenland and Hulu Cave records, which suggests a common forcing mechanism of DO cycles in the North Atlantic and monsoonal region of Asia. Centennial-scale monsoonal oscillations in the cave δ18O record are indicative of hydroclimatic instability during interstadials. After removing the signals of remote moisture sources, the proportion of moisture from nearby sources is found to be higher during stadials than during interstadials. To explain this, we propose that the movement of the westerly jet is an important control on the balance of nearby and distant moisture sources in East Asia. In addition, the records of δ13C and trace element ratios, which are proxies of local environmental changes, resemble the δ18O record on the scale of DO cycles, as well as on even shorter timescales. This suggests that hydrological processes and biological activity at the cave site respond sensitively to the monsoonal changes.
Computerized cognitive remediation therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects.
In total, 311 Chinese inpatients with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia were randomized to receive CCRT or Active control for 12 weeks with four to five sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The outcomes were cognition, clinical symptoms and functional outcomes.
There was a significant benefit in the MATRICS Consensus Cognitive Battery (MCCB) total score for CCRT (F1,258 = 5.62; p = 0.02; effect size was 0.27, 95% confidence interval 0.04–0.49). There were no specific moderators of CCRT improvements. However, across both groups, Wisconsin Card Sort Test improvement mediated a positive effect on functional capacity and Digit Span benefit mediated decreases in positive symptoms. In exploratory analyses younger and older participants showed cognitive improvements but on different tests (younger on Symbol Coding Test, while older on the Spatial Span Test). Only the older age group showed MSCEIT benefits at post-treatment. In addition, cognition at baseline negatively correlated with cognitive improvement and those whose MCCB baseline total score was around 31 seem to derive the most benefit.
CCRT can improve the cognitive function of patients with schizophrenia. Changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT.
Penetrative turbulent Rayleigh–Bénard convection which depends on the density maximum of water near
is studied using two-dimensional and three-dimensional direct numerical simulations. The working fluid is water near
with Prandtl number
. The considered Rayleigh numbers
. The density inversion parameter
varies from 0 to 0.9. It is found that the ratio of the top and bottom thermal boundary-layer thicknesses (
) increases with increasing
, and the relationship between
seems to be independent of
. The centre temperature
is enhanced compared to that of Oberbeck–Boussinesq cases, as
is related to
is also found to have a universal relationship with
which is independent of
. Both the Nusselt number
and the Reynolds number
decrease with increasing
, the normalized Nusselt number
and Reynolds number
also have universal relationships with
which seem to be independent of both
and the aspect ratio
. The scaling exponents of
are found to be insensitive to
despite of the remarkable change of the flow organizations.
The plerocercoid (sparganum) of Spirometra erinaceieuropaei is the main aetiological agent of human sparganosis. To improve the current knowledge on S. erinaceieuropaei evolution, we performed multi-locus microsatellite typing of sparganum isolates from China for the first time. All available expressed sequence tag (EST) sequences for the Spirometra were downloaded from the GenBank. The identification and localization of microsatellites in ESTs was accomplished by MISA. Based on the selected microsatellites, the genetic structure of 64 sparganum isolates collected from 11 geographical locations in southwest China were investigated through principal component analysis, STRUCTURE analysis and neighbour-joining clustering. A total of 522 non-redundant ESTs containing 915 simple sequence repeats were identified from 12 481 ESTs screened. Five primer pairs were finally selected. Using these loci, a total of 12 alleles were detected in 64 sparganum isolates. Little variability was observed within each of geographical population, especially among isolates derived from Kunming of Yunnan (YN-KM) province. Both STRUCTURE analysis and the clustering analysis supported that two genotypes existed among the sparganum isolates from southwest China. In conclusion, five microsatellite markers were successfully developed, and sparganum population was observed to harbour low genetic variation, further investigation with deeper sampling was needed to elucidate the population structure.
Graphene (G) has attracted great interest because of its excellent chemical and electrical properties. However, the aggregation of graphene restricts its application. Herein, linoleic acid sodium salt (LASS), a low-cost and environmentally friendly material, was used to improve the dispersion of graphene through covalent interaction. Then, the mixture (G@LASS) was integrated with acrylic resin matrix via hydrogen bond between the carboxyl and ester groups. The excellent interfacial compatibility between G@LASS and acrylic matrix, as well as good dispersibility of G@LASS, was demonstrated by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman, and scanning electron microscopy tests. Compared with acrylic matrix, the surface hydrophobicity of G@LASS@Acrylic increased considerably because of its compact structure. G@LASS@Acrylic composites meet the requirement of antistatic materials when the content of G was only about 0.5 wt%. The results showed that conductive pathways were established successfully through this method.
The study of the relationship among the manufacturing process, the structure and the property of materials can help to develop the new materials. The material images contain the microstructures of materials, therefore, the quantitative analysis for the material images is the important means to study the characteristics of material structures. Generally, the quantitative analysis for the material microstructures is based on the exact segmentation of the materials images. However, most material microstructures are shown with various shapes and complex textures in images, and they seriously hinder the exact segmentation of the component elements. In this research, machine learning method and complex networks method are adopted to the challenge of automatic material image segmentation. Two segmentation tasks are completed: on the one hand, the images of the titanium alloy are segmented based on the pixel-level classification through feature extraction and machine learning algorithm; on the other hand, the ceramic images are segmented with the complex networks theory. In the first task, texture and shape features near each pixel in titanium alloy image are calculated, such as Gabor filters, Hu moments and GLCM (Gray-Level Co-occurrence Matrix) etc.. The feature vector for the pixel can be obtained by arraying these features. Then, classification is performed with the random forest model. Once each pixel is classified, the image segmentation is completed. In the second task, a complex network structure is built for the ceramic image. Then, a clustering algorithm of complex network is used to obtain network connection area. Finally, the clustered network structure is mapped back to the image and getting the contours among the component elements. The experimental results demonstrate that these methods can accurately segment material images.
The evolution of carbides and the coarsening behavior of L12 ordered γ′ phase in Ni–25Cr–20Co alloys aged for varying time from 1000 to 5000 h at 700 and 750 °C were discussed in this paper. The mechanical properties of the alloys after aging were also discussed. Due to the changing of predominated resistance factor, a few of the γ′ precipitates’ shape changed from spherical to cuboidal after aging at 750 °C for 3000 h. The sizes and volume fraction of the γ′ precipitates were measured after aging at both temperatures. The experimentally determined temporal exponent of the γ′ coarsening indicated that the coarsening kinetics is in accordance with both models: the classical matrix diffusion LSW model and the trans-interface diffusion-controlled model. Additionally, the coarsening rate of the γ′ precipitates is dominated by the diffusion coefficients of Nb based on the classical LSW model. Furthermore, the yield strength curves of the alloys aged at 700 °C showed different trends at both test temperatures which is related to the influence of γ′ coarsening on the critical resolved shear stress.
To investigate the morphology and dimensions of the vestibular aqueduct on axial, single-oblique and double-oblique computed tomography images.
The computed tomography temporal bone scans of 112 patients were retrospectively evaluated. Midpoint and opercular measurements were performed using axial, single-oblique and double-oblique images. Morphometric analyses were also conducted. The vestibular aqueduct sizes on axial, single-oblique and double-oblique images were compared.
At the midpoint, the mean (± standard deviation) vestibular aqueduct measured 0.61 ± 0.23 mm, 0.74 ± 0.27 mm and 0.82 ± 0.38 mm on axial, single-oblique and double-oblique images, respectively; at the operculum, the vestibular aqueduct measured 0.91 ± 0.30 mm, 1.11 ± 0.45 mm and 1.66 ± 1.07 mm on the respective images. The co-efficients of variation of the vestibular aqueduct measured at the midpoint were 37.4 per cent, 36.5 per cent and 47.5 per cent on axial, single-oblique and double-oblique images, respectively; at the operculum, the measurements were 33.0 per cent, 40.5 per cent and 64.5 per cent. Regarding morphology, the vestibular aqueduct was fissured (33.5 per cent), tubular (64.3 per cent) or invisible (2.2 per cent).
The morphology and dimensions of the vestibular aqueduct were highly variable among axial, single-oblique and double-oblique images.
A precisely 230Th-dated stalagmite δ13C profile from Hulu Cave, China, is presented to characterize the frequency and pattern of millennial-scale Asian monsoon (AM) variability from 160.6 to 132.5 ka. Evidence for an antiphased relationship of the δ13C and δ18O on the millennial scale suggests that the δ13C is indicative of the local hydrological cycle associated with changes in AM strength. Owing to the δ13C responding to AM changes more sensitively than the δ18O, we could identify 15 strong AM events that correlate to cold intervals recorded in Antarctic ice cores within 230Th dating uncertainty. This result supports a dynamic link of AM strength and southern hemispheric climates via the cross-equatorial airflows. Power spectrum analysis shows a predominant periodicity of 1.5–2.5 ka for the δ13C profile, similar to the Dansgaard-Oeschger frequency during the last glacial period. Moreover, the AM events are characterized by rapid transitions at the onset, suggesting that the observed millennial-scale AM variability is likely forced by northern high-latitude climates via north–south shifts of the Intertropical Convergence Zone associated with the bipolar seesaw mechanism. As evidence for a common mechanism for ice age terminations, a strong AM event (~134 ka) surrounding Termination II is analogous to the Bølling-Allerød warming interval.
Owing to the development of new technologies, the epigenome, a second dimensional method for genome analysis has emerged. Epigenetic mechanisms, including DNA methylation, histone modifications and noncoding RNAs, regulate gene expression without changing the genetic sequence. These epigenetic mechanisms normally modulate gene expression, trans-generational effects and inherited expression states in various biological processes. Abnormal epigenetic patterns typically cause pathological conditions, including cancers, age-related diseases, and specific cartilage and bone diseases. Facing the rapidly developing epigenetic field, we reviewed epigenetic mechanisms and their involvement with the skeletal system and their role in skeletal development, homeostasis and degeneration. Finally, we discuss the prospects for the future of epigenetics.
The influence of tilt on flow reversals in two-dimensional thermal convection in rectangular cells with two typical aspect ratios,
and 2, are investigated by means of direct numerical simulations. For
, tilt tends to suppress flow reversals. However, it is found that flow reversals characterized by two main rolls are promoted by tilt for
, which are even observed for some cases of small Prandtl numbers (
) and large tilt angles (
). Different from level cases where the four corner rolls all have opportunities to grow and trigger a flow reversal, the reversals in an anticlockwise tilted cell with
are always led by the growth of the bottom-right or the top-left corner roll. Tilt is favourable for the growth of the bottom-right or the top-left corner roll and thus for breaking the balance between the two main rolls and triggering a flow reversal. The mode decomposition analysis shows that the appearance of the intermediate single-roll mode is crucial for reversals, and flow reversals in a tilted cell with
can be viewed as a mode competition process between single-roll mode and horizontally adjacent double-roll mode. They can only occur in a limited range of
where the two modes have comparable strength. Furthermore, the Nusselt numbers at the hot plate
and at the cold plate
behave differently during a flow reversal for
due to the preference of single corner roll growth.
In this paper, zircon U–Pb geochronology, major and trace elements, and Sr–Nd isotope geochemistry of the Baiyanghe dolerites in northern West Junggar of NW China are presented. The U–Pb dating of zircons from the dolerites yielded ages of 272.2±4 Ma and 276.7±6.2 Ma, which indicate the emplacement times. The dolerites are characterized by minor variations in SiO2 (46.89 to 49.07 wt%), high contents of Al2O3 (13.60 to 13.92 wt%) and total Fe2O3 (11.14 to 11.70 wt%), and low contents of MgO (2.67 to 3.64 wt%) and total alkalis (Na2O+K2O, 5.1 to 5.97 wt%, K2O/Na2O = 0.37–0.94), which indicate affinities to metaluminous tholeiite basalt. The REE pattern ((La/Sm)N = 2.25–2.34, (La/Yb)N = 7.42–8.36), V–Ti/1000 and 50*Zr–Ti/50–Sm discrimination diagrams show that these rocks are OIB-type. The high contents of Zr and Ti indicate a within-plate tectonic setting, and samples plot in the ‘plume source’ field shown on the Dy/Yb(N) versus Ce/Yb(N) diagram. The positive εNd(t) values (+7.09 to +7.48), high initial 87Sr/86Sr ratios (0.70442 to 0.70682) and depletions of Nb and Ta elements in the samples can be explained by the involvement of subducted sediments. In summary, it is possible that the Baiyanghe dolerites were derived from an OIB-like mantle source and associated with a mantle plume tectonic setting. Therefore, our samples provide the youngest evidence for the existence of a mantle plume, which may provide new insights into the Late Palaeozoic tectonic setting of West Junggar.
The effect of mold temperature on microstructure and mechanical properties of a rheo-squeeze casting (RSC) Mg–3Nd–0.2Zn–0.4Zr (NZ30K) alloy were investigated. The results indicated that the rise of mold temperature contributed to the increase of particle size and alloy density and the decrease of dislocation density. The rapid coarsening and then the normal growth of the particles during solution treatment were observed, and the long-rod-like Zn2Zr3 phase occurred. After age treatment, rod-like β′ precipitate was found in the conventional squeeze casting (CSC) alloy, while two types of precipitates including β′ phase and small plate-like β″ phase were observed in the RSC alloy. The amount of Zn2Zr3 phase was increased with rising mold temperature. Compared with the T6-treated CSC sample, the T6-treated RSC sample presented higher mechanical properties due to the larger precipitation strengthening contribution, and the yield strength, ultimate tensile strength, and elongation were up to 160 MPa, 296 MPa, and 7.7%.
Mg–3.0Y–2.5Nd–1.0Gd–xZn–0.5Zr (x = 0, 0.2, 0.5, and 1.0) (wt%) alloys were produced by metallic and sand mold casting to study the microstructure and mechanical properties of the alloys. The as-cast Zn-free alloys consist of α-Mg and eutectics, whereas the Zn-containing alloys contain additional long-period stacking ordered (LPSO) structures. With a higher solidification, the cooling rate brought by metallic mold casting, grains, and eutectics are refined, which enhances the elongation of the alloys, accompanied by a decrease of area fraction of the LPSO structure. Some residual eutectics in the Mg–3.0Y–2.5Nd–1.0Gd–1.0Zn–0.5Zr alloys act as obstacles to grain boundary migration during solution treatment, which make the average grain size 15–20 μm smaller than that of the other alloys and hence improve the elongation of the alloys. The Zn addition brings notable enhancements to mechanical properties of the alloys due to solid solution strengthening of Zn. Especially, the peak-aged Mg–3.0Y–2.5Nd–1.0Gd–0.5Zn–0.5Zr alloys perform with the highest overall tensile properties.
1-(4-methoxyphenyl)-7-oxo-6-[4-(2-oxopiperidin-1-yl)phenyl]-4,5,6,7- tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxylic acid ethyl ester is an important intermediate in the synthesis of the anticoagulant, apixaban. X-ray powder diffraction data for this compound are reported [a = 14.101(4) Å, b = 10.105(6) Å, c = 9.532(7) Å, α = 72.774(1)°, β = 97.356(3)°, γ = 108.237(3)°, unit-cell volume V = 1231.45 Å3, Z = 2, and space group P-1]. No detectable impurities were observed.
Cyclic deformation and low-cycle fatigue behavior of Mg–10Gd–3Y–0.5Zr alloy in sand-cast and aging treatment conditions (sand-cast-T6) were investigated by carrying out full reversed strain-controlled tension-compression tests at the strain amplitude ranging from 0.25 to 0.7%. The results show that stress–strain hysteresis loops of the studied alloys display near tension-compression symmetry, which is dominated by microstructure and strain amplitude. Both sand-cast and sand-cast-T6 alloys exhibit cyclic hardening and softening phenomenon with increasing loading cycles. Meanwhile, the fatigue life of the aged alloy is higher than that of the sand-cast alloy at all applied strain amplitudes. The theoretical strain fatigue limits (ε0) of sand-cast and sand-cast-T6 alloys are 2.1% and 2.3%, respectively. In addition, the low-cycle fatigue behavior of the studied alloy at different strain amplitudes was also investigated.
X-ray powder diffraction data, unit-cell parameters, and space group for Ethyl (Z)-2-chloro-2-[2-(4-methoxyphenyl)hydrazin-1-ylidene]acetate, C11H13ClN2O3, are reported [a = 13.308(4) Å, b = 9.908(5) Å, c = 4.753(4) Å, α = 90°, β = 91.510(8)°, γ = 90°, unit-cell volume V = 626.64 Å3, Z = 2, ρcal = 1.361 g cm−3, and space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurities were observed.
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.
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.
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.
Arteriosclerotic CMBs and periventricular white matter disintegrity seem to be independent MRI surrogated markers in the early stage of cognitive impairment in SVD.
We present two isotopic (δ18O and δ13C) sequences of a twin-stalagmite from Zhuliuping Cave, southwestern China, with 230Th dates from 14.6 to 4.6 ka. The stalagmite δ18O record characterizes orbital- to decadal-scale variability of Asian summer monsoon (ASM) intensity, with the Holocene optimum period (HOP) between 9.8 and 6.8 ka BP which is reinforced by its co-varying δ13C data. The large multi-decadal scale amplitude of the cave δ18O indicates its high sensitivity to climate change. Four centennial-scale weak ASM events during the early Holocene are centered at 11.2, 10.8, 9.1 and 8.2 ka. They can be correlated to cold periods in the northern high latitudes, possibly resulting from rapid dynamics of atmospheric circulation associated with North Atlantic cooling. The 8.2 ka event has an amplitude more than two-thirds that of the Younger Dryas (YD), and is significantly stronger than other cave records in the Asia monsoon region, likely indicating a more severe dry climate condition at the cave site. At the end of the YD event, the δ13C record lags the δ18O record by 300–500 yr, suggesting a multi-centennial slow response of vegetation and soil processes to monsoon enhancement.
A multi-region scene matching-based localisation system for automated navigation of Unmanned Aerial Vehicles (UAV) is proposed. This system may serve as a backup navigation error correction system to support autonomous navigation in the absence of a global positioning system such as a Global Navigation Satellite System. Conceptually, the system computes the location of the UAV by comparing the sensed images taken by an on board optical camera with a library of pre-recorded geo-referenced images. Several challenging issues in building such a system are addressed, including the colour variability problem and elimination of time-varying details from the pairs of images. The overall algorithm is an iterative process involving four sub-processes: firstly, exact histogram matching is applied to sensed images to overcome the colour variability issues; secondly, regions are automatically extracted from the sensed image where landmarks are detected via their colour histograms; thirdly, these regions are matched against the library, while eliminating inconsistent regions between underlying image pairs in the registration process; and finally the location of the UAV is computed using an optimisation procedure which minimises the localisation error using affine transformations. Experimental results demonstrate the proposed system in terms of accuracy, robustness and computational efficiency.