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Genome-wide association studies (GWAS) have consistently revealed that a variant of microRNA 137 (MIR137) shows a quite significant association with schizophrenia. Identifying the network of genes regulated by MIR137 could provide insights into the biological processes underlying schizophrenia. In addition, DLPFC functional connectivity, a robust correlate of MIR137, may provide plausible endophenotypes. However, the regulatory role of the MIR137 gene network in the disrupted functional connectivity remains unclear. Here, we tested the effects of the MIR137 regulated genes on the risk for schizophrenia and DLPFC functional connectivity.
To evaluate the additive effects of the MIR137 regulated genes (N = 1274), we calculated a MIR137 polygenic risk score (PRS) for schizophrenia and tested its association with the risk for schizophrenia in the genomic data of a Han Chinese population that included schizophrenia patients (N = 589) and normal controls (N = 575). We then investigated the association between MIR137 PRS and DLPFC functional connectivity in two independent young healthy cohorts (N = 356 and N = 314).
We found that the MIR137 PRS successfully captured the differences in genetic structure between the patients and controls, but the single gene MIR137 did not. We then consistently found that a higher MIR137 PRS was correlated with lower functional connectivities between the DLPFC and both the superior parietal cortex and the inferior temporal cortex in two independent cohorts.
The findings suggested that these two functional connectivities of the DLPFC could be important endophenotypes linking the MIR137-regulated genetic structure to schizophrenia.
Annexin A2 (ANXA2) is reported to be associated with cancer development. To investigate the roles ANXA2 plays during the development of cancer, the RNAi method was used to inhibit the ANXA2 expression in caco2 (human colorectal cancer cell line) and SMMC7721 (human hepatocarcinoma cell line) cells. The results showed that when the expression of ANXA2 was efficiently inhibited, the growth and motility of both cell lines were significantly decreased, and the development of the motility relevant microstructures, such as pseudopodia, filopodia, and the polymerization of microfilaments and microtubules were obviously inhibited. The cancer cell apoptosis was enhanced without obvious significance. The possible regulating pathway in the process was also predicted and discussed. Our results suggested that ANXA2 plays important roles in maintaining the malignancy of colorectal and hepatic cancer by enhancing the cell proliferation, motility, and development of the motility associated microstructures of cancer cells based on a possible complicated signal pathway.
Triploid and pentaploid breeding is of great importance in agricultural production, but it is not always easy to obtain double ploidy parents. However, in fishes, chromosome ploidy is diversiform, which may provide natural parental resources for triploid and pentaploid breeding. Both tetraploid and hexaploid exist in Schizothorax fishes, which were thought to belong to different subfamilies with tetraploid Percocypris fishes in morphology, but they are sister genera in molecule. Fortunately, the pentaploid hybrid fishes have been successfully obtained by hybridization of Schizothorax wangchiachii (♀, 2n = 6X = 148) × Percocypris pingi (♂, 2n = 4X = 98). To understand the genetic and morphological difference among the hybrid fishes and their parents, four methods were used in this study: morphology, karyotype, red blood cell (RBC) DNA content determination and inter-simple sequence repeat (ISSR). In morphology, the hybrid fishes were steady, and between their parents with no obvious preference. The chromosome numbers of P. pingi have been reported as 2n = 4X = 98. In this study, the karyotype of S. wangchiachii was 2n = 6X = 148 = 36m + 34sm + 12st + 66t, while that the hybrid fishes was 2n = 5X = 123 = 39m + 28sm + 5st + 51t. Similarly, the RBC DNA content of the hybrid fishes was intermediate among their parents. In ISSR, the within-group genetic diversity of hybrid fishes was higher than that of their parents. Moreover, the genetic distance of hybrid fishes between P. pingi and S.wangchiachii was closely related to that of their parental ploidy, suggesting that parental genetic material stably coexisted in the hybrid fishes. This is the first report to show a stable pentaploid F1 hybrids produced by hybridization of a hexaploid and a tetraploid in aquaculture.
Global Navigation Satellite System (GNSS) observations contain various errors, the separation and measurement of which is a popular research topic. Multipath effect on code measurements is investigated through the multipath combination, but carrier multipath error is small, and it is difficult to distinguish from other errors, such as hardware delay, carrier noise and satellite inherent biases. However, as the number of frequency points increases during the rapid development of GNSSs, it is possible to analyse the abovementioned errors in detail. Triple-frequency combination can be used to eliminate the first order ionospheric error, and a quad-frequency combination has one degree of freedom, which may be used to minimise carrier error effects. For this reason, an optimum method has been developed for multi-frequency GNSS code-multipath combination measurements, which has been verified by exploiting BeiDou System (BDS), three frequency data from an International GNSS Service (IGS) station and a city canyon as well as actual sampled quad-frequency data. By comparative analysis, we found that the fluctuations of an optimum triple-frequency combination are smaller than that of the non-optimum combination, which decreases the influence of inherent errors and biases on carrier phase. At the same time, second-order ionospheric error can be effectively eliminated as well. This provides a new code-multipath combination measurement optimisation methodology for future multi-frequency BDS and other GNSSs.
Subacute ruminal acidosis (SARA) can increase the level of inflammation and induce rumenitis in dairy cows. Berberine (BBR) is the major active component of Rhizoma Coptidis, which is a type of Chinese anti-inflammatory drug for gastrointestinal diseases. The purpose of this study was to investigate the anti-inflammatory effects of BBR on lipopolysaccharide (LPS)-stimulated rumen epithelial cells (REC) and the underlying molecular mechanisms. REC were cultured and stimulated with LPS in the presence or absence of different concentrations of BBR. The results showed that cell viability was not affected by BBR. Moreover, BBR markedly decreased the concentrations and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6 in the LPS-treated REC in a dose-dependent manner. Importantly, Western blotting analysis showed that BBR significantly suppressed the protein expression of toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein (MyD88) and the phosphorylation of nuclear factor-κB (NF-κB), inhibitory kappa B (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in LPS-treated REC. Furthermore, the results of immunocytofluorescence showed that BBR significantly inhibited the nuclear translocation of NF-κB p65 induced by LPS treatment. In conclusion, the protective effects of BBR on LPS-induced inflammatory responses in REC may be due to its ability to suppress the TLR4-mediated NF-κB and MAPK signaling pathways. These findings suggest that BBR can be used as an anti-inflammatory drug to treat inflammation induced by SARA.
The influence of the nozzle aspect ratio (
, 2 and 4), stroke length (
, 3.7 and 5.55) and Reynolds number (
, 158, 316 and 632) on the behaviour of elliptic synthetic jets is studied experimentally. Laser-induced fluorescence and two-dimensional and stereoscopic particle image velocimetry are used to analyse the vortex dynamics and evolution mechanism. It is found that the fluid elements around the major axis of an elliptic vortex ring move downstream faster and tend to approach the centreline, while the fluid elements around the minor axis move downstream at a slower speed and away from the centreline, thereby resulting in the occurrence of the well-known axis-switching phenomenon for elliptic synthetic jets. During this process, a pair of arc-like vortices forms ahead of the primary vortex ring, and they are constituted by streamwise vortices in the leg part and spanwise vortices in the head part; two pairs of streamwise vortices form from the inside of the primary vortex ring and develop in the tails. The streamwise vortices are pushed away progressively from the centreline by the synthetic jet vortex rings that are formed during the subsequent periods. These additional vortical structures for non-circular synthetic jets show regular and periodic characteristics, which are quite different from the previous findings for non-circular jets. Their mutual interaction with the vortex ring causes significant changes in the topology of elliptic synthetic jets, which further results in the variation of the statistical characteristics. Increasing the aspect ratio, stroke length and Reynolds number will make the evolution of the synthetic jet become more unstable and complex. In addition, the entrainment rate of an elliptical synthetic jet is larger than that of a circular synthetic jet and it increases with the nozzle aspect ratio (
) and Reynolds number. It is indicated that the formation of streamwise vortices could enhance the entrainment rate. This finding provides substantial evidence for the potential application of elliptic synthetic jets for effective flow control.
A new linear and conservative finite difference scheme which preserves discrete mass and energy is developed for the two-dimensional Gross–Pitaevskii equation with angular momentum rotation. In addition to the energy estimate method and mathematical induction, we use the lifting technique as well as some well-known inequalities to establish the optimal
-error estimate for the proposed scheme with no restrictions on the grid ratio. Unlike the existing numerical solutions which are of second-order accuracy at the most, the convergence rate of the numerical solution is proved to be of order
with time step
and mesh size
. Numerical experiments have been carried out to show the efficiency and accuracy of our new method.
In January 2016, static GPS measurements were carried out in a 30 × 30 km2 area centered around Kunlun station at Dome Argus (Dome A), East Antarctica, to acquire high-precision 3-D geodetic coordinates at 49 sites. By comparing the coordinates with previous GPS measurements in 2008 and 2013 at the same sites, we constructed a detailed and long-term record of the ice-surface velocity field, 2008–2016, around Dome A. During this time span, the estimated ice-surface velocity ranges from 0.8 ± 0.3 to 28.7 ± 1.6 cm a−1, with a mean of 10.4 ± 0.3 cm a−1. From 2013 to 2016, the surface elevation of most Dome A areas exhibits a rising trend, and the maximum increase of snow surface elevation is 84.8 cm. The mean snow surface elevation change rate at Dome A is estimated to be 6.6 ± 0.7 cm a−1. The difference of 1.0 cm a−1 between the snow surface change rate derived from GPS and pole-height change rate from surface mass balance is suspected to be a result of a combination of firn densification and basal melt under Dome A.
Seed germination, the first and critical step of the plant's life cycle, is affected by salt stress. However, the underlying mechanism of salt tolerance during early seed germination remains elusive. Here, a comparative RNA-seq analysis was performed using early germinating seeds either under normal conditions or in 100 and 150 mM sodium chloride. A total of 575 genes were up-regulated and 913 genes were down-regulated in the presence of 100 mM NaCl. Under the 150 mM NaCl treatment 1921 genes were up-regulated and 3501 genes were down-regulated. A total of 379 or 863 genes were up-regulated or down-regulated in both 100 and 150mM NaCl. These co-regulated genes were further analysed by GO enrichment. Genes in the categories abscisic acid signaling and synthesis and nutrient reservoir activity were significantly enriched in the up-regulated genes. Transcription factors responsive to gibberellin and auxin were significantly down-regulated by salinity stress. Genes related to anti-oxidant activity were significantly enriched in the down-regulated gene clusters by NaCl treatment. Our results suggest that salt stress inhibits seed germination by activating ABA synthesis and signalling, and depressing GA and auxin signalling, while preserving nutrition and down-regulated anti-oxidant activity. Our study provides more insight into the molecular mechanism of salt tolerance during early seed germination.
Nanocrystalline and nanolaminated materials show enhanced radiation tolerance compared with their coarse-grained counterparts, since grain boundaries and layer interfaces act as effective defect sinks. Although the effects of layer interface and layer thickness on radiation tolerance of crystalline nanolaminates have been systematically studied, radiation response of crystalline/amorphous nanolaminates is rarely investigated. In this study, we show that irradiation can lead to formation of nanocrystals and nanotwins in amorphous CuNb layers in Cu/amorphous-CuNb nanolaminates. Substantial element segregation is observed in amorphous CuNb layers after irradiation. In Cu layers, both stationary and migrating grain boundaries effectively interact with defects. Furthermore, there is a clear size effect on irradiation-induced crystallization and grain coarsening. In situ studies also show that crystalline/amorphous interfaces can effectively absorb defects without drastic microstructural change, and defect absorption by grain boundary and crystalline/amorphous interface is compared and discussed. Our results show that tailoring layer thickness can enhance radiation tolerance of crystalline/amorphous nanolaminates and can provide insights for constructing crystalline/amorphous nanolaminates under radiation environment.
This paper introduces recent activities on Marx-based compact repetitive pulsed power generators at the Institute of Applied Electronics (IAE), China Academy of Engineering Physics (CAEP), over the period 2010–2018. A characteristic feature of the generators described is the use of a simplified bipolar charged Marx circuit, in which the normal isolation resistors or inductors to ground are removed to make the circuit simpler. Several pulse-forming modules developed to generate a 100 ns square wave output are introduced, including thin-film dielectric lines of different structures, a pulse-forming line based on a Printed Circuit Board, and non-uniform pulse-forming networks. A compact repetitive three-electrode spark gap switch with low-jitter, high-voltage, and high-current was developed and is used in the generators. A positive and negative series resonant constant current power supply with high precision and high power is introduced. As an important part of the repetitive pulse power generator, a lower jitter pulse trigger source is introduced. Several typical high-power repetitive pulsed power generators developed at IAE are introduced including a 30 GW low-impedance Marx generator, a compact square-wave pulse generator based on Kapton-film dielectric Blumlein line, a 20 GW high pulse-energy repetitive PFN-Marx generator, and a coaxial Marx generator based on ceramic capacitors. The research of key technologies and their development status are discussed, which can provide a reference for the future development and application of miniaturization of compact and repetitive Marx generators.
Highly dense zirconia dental ceramic coatings were fabricated by aqueous electrophoretic deposition (EPD) and subsequently sintered between 1250 and 1450 °C. Microstructural examination revealed that aqueous EPDZrO2 coatings possessed a tetragonal phase structure and the grain size increased with increasing sintering temperature. Nanoindentation study proved that the aqueous EPDZrO2 coating also had excellent mechanical properties. The effect of different applied loads on hardness and elastic modulus of the 1350 °C-sintered sample at room temperature was investigated by the method of progressive multicycle measurement nanoindentation. The simulative experiment proved that hardness of aqueous EPDZrO2 exhibited reverse indentation size effect (ISE) behavior and then displayed the normal ISE response. The analysis indicates that the reverse ISE is attributed to the relaxation of surface stresses resulting from indentation cracks at small loads and normal ISE is caused by geometrically necessary dislocations. The tetragonal–monoclinic stress-induced phase transformation during nanoindentation is the primary cause of dental zirconia failures.
In situ U–Pb and Hf analyses were used for crustal zircon xenocrysts from Triassic kimberlites exposed in the Rangnim Massif of North Korea to identify components of the basement hidden in the deep crust of the Rangnim Massif and to clarify the crustal evolution of the massif. The U–Pb age spectrum of the zircons has a prominent population at 1.9–1.8 Ga and a lack of Archaean ages. The data indicate that the deep crust and basement beneath the Rangnim Massif are predominantly of Palaeoproterozoic age, consistent with the ages of widely exposed Palaeoproterozoic granitic rocks. In situ zircon Hf isotope data show that most of the Palaeoproterozoic zircon xenocrysts have negative ϵHf(t) values (−9.7 to +0.7) with an average Hf model age of 2.86 ± 0.02 Ga (2σ), which suggests that the Palaeoproterozoic basement was not juvenile but derived from the reworking of Archaean rocks. Considering the existence of Archaean remanent material in the Rangnim Massif and their juvenile features, a strong crustal reworking event is indicated at 1.9–1.8 Ga, during which time the pre-existing Archaean basement was exhausted and replaced by a newly formed Palaeoproterozoic basement. These features suggest that the Rangnim Massif constitutes the eastern extension of the Palaeoproterozoic Liao–Ji Belt of the North China Craton instead of the Archaean Liaonan Block as previously thought. A huge Palaeoproterozoic orogen may exist in the eastern margin of the Sino-Korean Craton.
Rabies is one of the major public health problems in China, and the mortality rate of rabies remains the highest among all notifiable infectious diseases. A meta-analysis was conducted to investigate the post-exposure prophylaxis (PEP) vaccination rate and risk factors for human rabies in mainland China. The PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese Science and Technology Periodical and Wanfang databases were searched for articles on rabies vaccination status (published between 2007 and 2017). In total, 10 174 human rabies cases from 136 studies were included in this meta-analysis. Approximately 97.2% (95% confidence interval (CI) 95.1–98.7%) of rabies cases occurred in rural areas and 72.6% (95% CI 70.0–75.1%) occurred in farmers. Overall, the vaccination rate in the reported human rabies cases was 15.4% (95% CI 13.7–17.4%). However, among vaccinated individuals, 85.5% (95% CI 79.8%–83.4%) did not complete the vaccination regimen. In a subgroup analysis, the PEP vaccination rate in the eastern region (18.8%, 95% CI 15.9–22.1%) was higher than that in the western region (13.3%, 95% CI 11.1–15.8%) and this rate decreased after 2007. Approximately 68.9% (95% CI 63.6–73.8%) of rabies cases experienced category-III exposures, but their PEP vaccination rate was 27.0% (95% CI 14.4–44.9%) and only 6.1% (95% CI 4.4–8.4%) received rabies immunoglobulin. Together, these results suggested that the PEP vaccination rate among human rabies cases was low in mainland China. Therefore, standardised treatment and vaccination programs of dog bites need to be further strengthened, particularly in rural areas.
National policies target healthcare-associated infections using medical claims and National Healthcare Safety Network surveillance data. We found low concordance between the 2 data sources in rates and rankings for surgical site infection following colon surgery in 155 hospitals, underscoring the limitations in evaluating hospital quality by claims data.
Since the late 1990s, hand, foot and mouth disease (HFMD) has become a common health problem that mostly affects children and infants in Southeast and East Asia. Global climate change is considered to be one of the major risk factors for HFMD. This study aimed to assess the correlation between meteorological factors and HFMD in the Asia-Pacific region. PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang Data and Weipu Database were searched to identify relevant articles published before May 2018. Data were collected and analysed using R software. We searched 2397 articles and identified 51 eligible papers in this study. The present study included eight meteorological factors; mean temperature, mean highest temperature, mean lowest temperature, rainfall, relative humidity and hours of sunshine were positively correlated with HFMD, with correlation coefficients (CORs) of 0.52 (95% confidence interval (CI) 0.42–0.60), 0.43 (95% CI 0.23–0.59), 0.43 (95% CI 0.23–0.60), 0.27 (95% CI 0.19–0.35), 0.19 (95% CI 0.02–0.35) and 0.19 (95% CI 0.11–0.27), respectively. There were sufficient data to support a negative correlation between mean pressure and HFMD (COR = −0.51, 95% CI −0.63 to −0.36). There was no notable correlation with wind speed (COR = 0.10, 95% CI −0.03 to 0.23). Our findings suggest that meteorological factors affect the incidence of HFMD to a certain extent.