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An actively controllable cascaded proton acceleration driven by a separate 0.8 picosecond (ps) laser is demonstrated in proof-of-principle experiments. MeV protons, initially driven by a femtosecond laser, are further accelerated and focused into a dot structure by an electromagnetic pulse (EMP) on the solenoid, which can be tuned into a ring structure by increasing the ps laser energy. An electrodynamics model is carried out to explain the experimental results and show that the dot-structured proton beam is formed when the outer part of the incident proton beam is optimally focused by the EMP force on the solenoid; otherwise, it is overfocused into a ring structure by a larger EMP. Such a separately controlled mechanism allows precise tuning of the proton beam structures for various applications, such as edge-enhanced proton radiography, proton therapy and pre-injection in traditional accelerators.
The discovery that blazars dominate the extra-galactic $\gamma$-ray sky is a triumph in the Fermi era. However, the exact location of $\gamma$-ray emission region still remains in debate. Low-synchrotron-peaked blazars (LSPs) are estimated to produce high-energy radiation through the external Compton process, thus their emission regions are closely related to the external photon fields. We employed the seed factor approach proposed by Georganopoulos et al. It directly matches the observed seed factor of each LSP with the characteristic seed factors of external photon fields to locate the $\gamma$-ray emission region. A sample of 1 138 LSPs with peak frequencies and peak luminosities was adopted to plot a histogram distribution of observed seed factors. We also collected some spectral energy distributions (SEDs) of historical flare states to investigate the variation of $\gamma$-ray emission region. Those SEDs were fitted by both quadratic and cubic functions using the Markov-chain Monte Carlo method. Furthermore, we derived some physical parameters of blazars and compared them with the constraint of internal $\gamma\gamma$-absorption. We find that dusty torus dominates the soft photon fields of LSPs and most $\gamma$-ray emission regions of LSPs are located at 1–10 pc. The soft photon fields could also transition from dusty torus to broad line region and cosmic microwave background in different flare states. Our results suggest that the cubic function is better than the quadratic function to fit the SEDs.
A 1178 J near diffraction limited 527 nm laser is realized in a complete closed-loop adaptive optics (AO) controlled off-axis multi-pass amplification laser system. Generated from a fiber laser and amplified by the pre-amplifier and the main amplifier, a 1053 nm laser beam with the energy of 1900 J is obtained and converted into a 527 nm laser beam by a KDP crystal with 62% conversion efficiency, 1178 J and beam quality of 7.93 times the diffraction limit (DL). By using a complete closed-loop AO configuration, the static and dynamic wavefront distortions of the laser system are measured and compensated. After correction, the diameter of the circle enclosing 80% energy is improved remarkably from 7.93DL to 1.29DL. The focal spot is highly concentrated and the 1178 J, 527 nm near diffraction limited laser is achieved.
The recent scientific progress has shown the promising effect of the vaccine in immunotherapy of cancer, which relies on the antigen processing/presentation capability of dendritic cells (DCs). As a result, cancer vaccines targeting DC, which also named as DC vaccine, was a hot-spot in vaccine development. Herein, a nanostructured lipid carrier (NLC) was employed to load chlorin e6 (Ce6) to serve as a potential in situ DC vaccine (NLC/Ce6) for effective immunotherapy of gastric cancer. Taking advantage of the photodynamic effect of Ce6 to generate reactive oxygen species (ROS) under laser irradiation, the NLC/Ce6 was able to trigger cell death and expose tumor-associated antigen (TAA). Moreover, mimicking the natural inflammatory response, the ROS can also recruit the DC for the effective processing/presentation of the in situ exposed TAA. As expected, we observed strong capability DC vaccination efficacy of this platform to effectively inhibit the growth of both primary and distant gastric tumors.
We describe 14 yr of public data from the Parkes Pulsar Timing Array (PPTA), an ongoing project that is producing precise measurements of pulse times of arrival from 26 millisecond pulsars using the 64-m Parkes radio telescope with a cadence of approximately 3 weeks in three observing bands. A comprehensive description of the pulsar observing systems employed at the telescope since 2004 is provided, including the calibration methodology and an analysis of the stability of system components. We attempt to provide full accounting of the reduction from the raw measured Stokes parameters to pulse times of arrival to aid third parties in reproducing our results. This conversion is encapsulated in a processing pipeline designed to track provenance. Our data products include pulse times of arrival for each of the pulsars along with an initial set of pulsar parameters and noise models. The calibrated pulse profiles and timing template profiles are also available. These data represent almost 21 000 h of recorded data spanning over 14 yr. After accounting for processes that induce time-correlated noise, 22 of the pulsars have weighted root-mean-square timing residuals of $<\!\!1\,\mu\text{s}$ in at least one radio band. The data should allow end users to quickly undertake their own gravitational wave analyses, for example, without having to understand the intricacies of pulsar polarisation calibration or attain a mastery of radio frequency interference mitigation as is required when analysing raw data files.
The aim of this study was to analyze the profile of chest injuries, oxygen therapy for respiratory failure, and the outcomes of victims after the Jiangsu tornado, which occurred on June 23, 2016 in Yancheng City, Jiangsu Province, China.
Methods:
The clinical records of 144 patients referred to Yancheng City No.1 People’s Hospital from June 23 through June 25 were retrospectively investigated. Of those patients, 68 (47.2%) sustained major chest injuries. The demographic details, trauma history, details of injuries and Abbreviated Injury Scores (AIS), therapy for respiratory failure, surgical procedures, length of intensive care unit (ICU) and hospital stay, and mortality were analyzed.
Results:
Of the 68 patients, 41 (60.3%) were female and 27 (39.7%) were male. The average age of the injured patients was 57.1 years. Forty-six patients (67.6%) suffered from polytrauma. The mean thoracic AIS of the victims was calculated as 2.85 (SD = 0.76). Rib fracture was the most common chest injury, noted in 56 patients (82.4%). Pulmonary contusion was the next most frequent injury, occurring in 12 patients (17.7%). Ten patients with severe chest trauma were admitted to ICU. The median ICU stay was 11.7 (SD = 8.5) days. Five patients required intubation and ventilation, one patient was treated with noninvasive positive pressure ventilation (NPPV), and four patients were treated with high-flow nasal cannula (HFNC). Three patients died during hospitalization. The hospital mortality was 4.41%.
Conclusions:
Chest trauma was a common type of injury after tornado. The most frequent thoracic injuries were rib fractures and pulmonary contusion. Severe chest trauma is usually associated with a high incidence of respiratory support requirements and a long length of stay in the ICU. Early initiation of appropriate oxygen therapy was vital to restoring normal respiratory function and saving lives. Going forward, HFNC might be an effective and well-tolerated therapeutic addition to the management of acute respiratory failure in chest trauma.
The switching between a damped and an undamped Inertial Navigation System (INS) is an important technical method to ensure its long-term accuracy. The stability of switching is of great importance. This paper studies the switching stability problem between a damped and an undamped INS. A model of an inertial navigation switching system is established by introducing switched control. The average dwell time method is used to analyse stability and a sufficient condition of exponential stability is given. The condition is also extended to the switched system containing constant disturbance and the sufficient condition of exponential stability. The effect of introducing switched control for the smooth operation of the system is verified and the accuracy of a long-term INS is improved effectively.
Previous studies have inferred a strong genetic component in schizophrenia. However, the genetic variants involved in the susceptibility to schizophrenia remain unclear.
Aims
To detect potential gene pathways and networks associated with schizophrenia, and to explore the relationship between common and rare variants in these pathways and abnormal white matter integrity in schizophrenia.
Method
The analysis included 100 first-episode treatment-naïve patients with schizophrenia and 140 healthy controls. A network-based analysis was carried out on the data collected from the Psychiatric Genomics Consortium Phase I (PGC-I). Based on our genome-wide association study and whole-exome sequencing data-sets, we performed a gene-set analysis to detect associations between the combining effects of common and rare genetic variants and abnormal white matter integrity in schizophrenia.
Results
Patients had significantly reduced functional anisotropy in the left and right anterior cingulate cortex, left and right precuneus and extra-nuclear (t = 4.61–5.10, PFDR < 0.01), compared with controls. Generated from co-expression network analysis of the PGC-1 summary statistics of schizophrenia, a subnetwork of 207 genes associated with schizophrenia was identified (P < 0.01), and 176 genes were co-expressed in four gene modules. Functional enrichment analysis for genes in each module revealed that the yellow module was enriched with highly co-expressed, innate immune response genes. Furthermore, rare variants of enriched genes in the yellow module were associated with reduced functional anisotropy in the left anterior cingulate cortex (P = 0.006; Padjusted = 0.024) in patients only.
Conclusions
The pathogenesis of schizophrenia may be substantially influenced by genes involved in the immune system, via both pathway and network.
The propagation of a pre-existing center crack in single crystal tungsten under cyclic loading was examined by molecular dynamics (MD) simulations at various temperatures. The results indicated that the deformation mechanism and fracture behavior at crack tip were differences for variously oriented cracks. The [001](010) crack propagated as the form of the formation of slip, while the deformation mechanisms of [10−1](101) crack were blunting voids at 300 K. At higher temperature, many more slip systems were activated resulting in the change of mode of crack propagation. Simulated results showed that the effect of temperature on deformation mechanism and fracture behavior of [001](010) crack was more sensitive than that of [10−1](101) crack. Meanwhile, the influence of a 5〈310〉{110} model grain boundary (GB) on crack propagation was also discussed. Detailed analysis showed that the grain boundary resisted the crack growth by changing the deformation mechanisms and the path of crack propagation at crack tip before the crack reached the grain boundary, and had an important influence on the crack growth rate.
Although the brittle material in analogue models is characterized by a linear Navier-Coulomb behaviour and rate-independent deformation, the geometry and style of deformation in accretionary wedges is sensitive to shortening velocity. In this study we have constructed a series of analogue models with various shortening velocities in order to study the influence of shortening velocity on the geometry and kinematics of accretionary wedges. Model results illustrate how shortening velocity has an important influence on the geometry and kinematics of the resulting wedge. In general, for models having similar bulk shortening, the accretionary wedges with higher velocities of shortening are roughly steeper, higher and longer, as well as having larger critical wedge angles and height. It accommodates a number of foreland-vergent thrusts, larger fault spacing and displacement rates than those of low- to medium-velocity shortening, which indicates a weak velocity-dependence in geometry of the wedge. Moreover, models with a high velocity of shortening undergo larger amounts of volumetric strain and total layer-parallel shortening than models with low- to medium-velocity shortening. The former accommodate a greater development of back thrusts and asymmetric structures; a backwards-to-forwards style of wedge growth therefore occurs in the frontal zone under high-velocity shortening.
For a subfunction u, associated with the stationary Schrödinger operator, which is dominated on the boundary by a certain function on a cone, we generalise the classical Phragmén-Lindelöf theorem by making an a-harmonic majorant of u.
The aim of this study was to evaluate the antioxidant, antihypertensive and immunomodulatory characteristics of skim milk fermented with Lactobacillus delbrueckii ssp. bulgaricus LB340. Supernatants obtained from the ferments after centrifugation were subjected to ultrafiltration and yielded four peptidic fractions of 10–5 kDa, 5–3 kDa, 3–1 kDa, and <1·0 kDa. Peptides in 5–3 kDa range exhibited a good antioxidant activity. The peptides (<1·0 k) was applied to Superdex-30 G column fractionation and produced six fractions (F1–6). Fraction F2 presented the highest angiotensin I-converting enzyme inhibition activity with IC50 of 67·71±7·62 mg/ml. Moreover, fraction F6, which displayed a good immunomodulatory activity, had a positive effect on murine spleen lymphocyte proliferation with Stimulation Index of 0·729±0·123. The present data showed the potential of the milk fermented with Lactobacillus delbrueckii ssp. bulgaricus LB340 as a functional food, however, further research is needed to evaluate the biofunctional activity of this fermentation product in vivo using model animal.
Phenotypic information about several pig meat quality traits on 334 Large White × Meishan F2 pigs was collected. Effects of the association of the FokI variants in the seventh intron of the skeletal muscle glycogen synthase (GYS1) gene and the PstI variants in the ninth intron of the palmitoyl acyl-CoA oxidase 1 (ACOX1) gene on the meat quality traits were examined on all pigs. The FokI variants of the GYS1 gene showed significant effects on pH of m. semipinalis capitis (P < 0.05). Linkage analysis indicated that the peak of the quantitative trait loci (QTL) curve was located around this marker for pH, but it did not reach significance (P > 0.05). The results may be due to several reasons such as linkage disequilibrium to the causal mutations, the limited number of animals or balance of another QTL or marker with negative effects. Significant effects of PstI variants of ACOX1 gene were also found on meat colour value and meat marbling score of both m. longissimus dorsi and m. biceps femoris (P < 0.05). Dominant effects for the affected traits at those two loci were significant except for meat marbling score of m. biceps femoris (P < 0.05). The results of this study give us some evidence for the potential of those dominant markers used in the marker-assisted selection of crossbreeding of the Large White pig sire lines and Meishan-derived synthetic dam lines.
The ferromagnetic/nonmagnetic (FM/NM) interfacial effects on the spin accumulation in the free layer were studied in a pseudo-spin-valve structure (PSVs) consisting of two FM layers separated by a NM spacer layer. We developed a spin current model for the current-induced magnetic switching (CIMS) effect based on the spin diffusion equations and appropriate boundary conditions, and derived a new formula for the spin-dependent electrochemical potentials that are related to the spin-dependent density of states. The results indicate that the spin accumulation in the free layer mainly depends on the interfacial spin asymmetry coefficient Ξ?which originates from the spin-dependent interfacial conductance. In the parallel (anti-parallel) configuration of the magnetization direction for the free and fixed layer, the positive (negative) electron current (electrons from the free layer to the fixed layer and vice versa) drives the spin current polarization factor at the interface between the top electrode and the free layer to vary from Ξ? (-Ξ?) to 0, while at the interface between the free layer and the spacer layer the spin current polarization factor vary from Ξ? (0) to Ξ?/2, which means the total spin current polarization factor in the free layer varies from 0 (Ξ?) to Ξ?/2. These results show that the anti-parallel configuration has a less critical switching current than that of the parallel configuration. Thus, we can design PSVs with symmetrical critical current based on the model.
The current induced magnetic dynamics of a nano-scale pseudo-spin-valve (PSV) structure was theoretically studied. The spin relaxation mechanisms and the influence of ferromagnetic/nonmagnetic (FM/NM) interfaces on the current polarization were investigated, and a modified magnetic dynamic equation was developed. Both the free layer's local magnetic moments and itinerant electrons' spins were regarded as a macro-spin, whose movement was resulted from two items: spin relaxation due to the magnetic damping and spin accumulation due to the polarized current. The injected current not only produces a spin transfer torque, but also alters the effective magnetic field, and thus affects the damping. Therefore, the damping is nonlinear and correlated to the current. Based on the analysis of the competition between magnetic damping and spin accumulation, the dynamic behaviors of magnetization switching and oscillation can be explained.
The molecular genetic characteristics were evaluated, and the genetic effects of marker loci on heterosis of three traits (birth weight, BWT; average daily gain, ADG; and feed and meat ratio, FMR) were analysed in the experimental pig populations: Yorkshire (Y, n=34), Landrace (L, n=46) and Meishan (M, n=55); Yorkshire×Landrace (YL, n=32) and its reciprocal (LY, n=36), Yorkshire×Meishan (YM, n=82) and its reciprocal (MY, n=47), by 39 microsatellite markers selected from pig chromosomes SSC4, 6, 7, 8 and 13. The results indicated that observed alleles ranged from 2 to 6, average 4.13, observed heterozygosity varied from 0.39 (Y) to 0.58 (YM+MY) and average polymorphism information content (PIC) varied from 0.33 (Y) to 0.5 (YM). There were two loci (sw2155 and sw1037) at which the alleles were fixed in Y and L, and there were three loci (sw2409, sw2454 and sw1691) at which the alleles were fixed in M. The results from heterozygosity and kinship analysis revealed an intrinsic genetic relationship among the seven populations. Furthermore, the results on genetic effect analysis indicate that several marker loci had a significant effect on heterosis of the three traits in the two different F1 crossbred populations (P⩽0.01), for example s0161, swr1130 and sw1856 for BWT, sw1856 and swr2036 for ADG, and sw1302 and swr2036 for FMR. The significant marker loci implied a deep genetic relationship between molecular marker loci and heterosis.
To increase our understanding of the relationships of trunk fat mass (FMtrunk) and four anthropometric indices in Chinese males, 1090 males aged 20–40 years were randomly recruited from the city of Changsha, China. Waist circumference (WC) and hip circumference (HC) were measured using standardized equipment, and three other anthropometric indices of BMI, waist:hip ratio (WHR) and conicity index (CoI) were calculated using weight, height, HC and WC. FMtrunk (in kg) was measured using a Hologic QDR 4500 W dual-energy X-ray absorptiometry scanner. There was an increasing trend of FMtrunk, %FMtrunk (percentage of FMtrunk) and BMI, WC, WHR, CoI in successively older age groups (e.g. the mean FMtrunk values were 4·63 (sd 2·58), 5·39 (sd 2·74), 5·93 (sd 2·82), 6·57 (sd 2·94) in four 5-year age groups, respectively). FMtrunk and %FMtrunk were significantly correlated with four anthropometric indices with the Pearson's correlation coefficients ranging from 0·25 to 0·86. Principal component analysis was performed to form three principal components that interpreted over 99·5% of the total variation of four related anthropometric indices in all age groups, with over 65% of the total variation accounted by principal component 1. Multiple regression analyses showed that three principal components explained a greater variance (R2 70·0–80·1%) in FMtrunk than did BMI or WC alone (R2 57·8–74·1%). The present results suggest that there is an increasing trend of FMtrunk and four anthropometric indices in successively older age groups; that age has important effects on the relationships of FMtrunk and studied anthropometric indices; and that the accuracy of predicting FMtrunk using four anthropometric indices is higher than using BMI or WC alone.
In order to reveal the molecular basis of heterosis, Large White (LW), an introduced European pig breed, and Meishan (MS), a Chinese indigenous pig breed, were selected to hybridize directly and reciprocally in the present experiment. mRNA differential display (DD) technique was performed to identify genes that were differentially expressed in the backfat tissues of hybrids (LW×MS, MS×LW) and purebred (LW×LW, MS×MS) pigs. The ten anchor primers in combination with ten arbitrary primers (100 sets in total) were used and nearly 1500 reproducible bands were observed in polyacrylamide gels. The 40 differentially displayed bands were selected for cloning and sequencing. Thirty-six out of 40 expressed sequence tags (ESTs) proved to be novel and the sequences were submitted to GenBank (accession No. CV507051-CV507087); the other four showed similarity to known genes published in GenBank. Three among 36 novel ESTs were chosen for further identification with semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The result showed that two ESTs were differentially expressed, and the third showed no obvious difference between hybrids and purebreds. In order to reduce the percentage of false-positive DD, RNA pools of four types of pigs were constructed, by mixing samples from six pigs of the same genotype, and subjected to DD. Stringent annealing temperature was applied and only bands that could be repeated in duplicate PCR were used for further study. The results showed that the expression pattern of these 36 ESTs differed among the four genotypes of pigs, suggesting that the genes corresponding to these differentially expressed ESTs might be related to the heterosis occurring in fat tissue.
By using the transient-null-current method, we have measured the internal electric field profiles Ei(x) near the p/i interface for two groups of solar cells: (a) a-Si:H p-i-n solar cells with varied i-layer thicknesses, and (b) a-SiGe:H cells with varied Ge content. When using an exponential function of Ei(x) to fit the experimental results, we obtained the field strength at the p/i interface E0, the screening length Lo, and the density of defect states Nd in the i-layer. The thinner the i-layer, the stronger the field strength obtained. For i-layer thickness increasing from 0.1 to 0.5 μm, the field strength E0 decreases from 1.15×105 to 2.0×104 V/cm; Lo decreases from 0.89 to 0.14 μm; and Nd is 3-4×1016 (cm3eV)−1. For the a-SiGe:H cells, as the Ge content increases from 40 to 55 %, E0 increases from 9.3×104 to 1.2×105 V/cm. The correlation of the internal electric field parameters with the cell‘s performance is discussed.