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There is growing evidence that suggests the association of vitamin D status with the development and progression of heart failure (HF). The objective of the present study is to assess the impact of concentration of serum 25-hydroxyvitamin D (25(OH)D) on cardiac prognosis in patients with HF. Between 1 January 2015 and 31 December 2016, we consecutively recruited patients with HF. Patients were followed prospectively for a median duration of 1 year. Serum concentration of 25(OH)D was measured with competitive chemiluminescent immunoassay. The endpoints were cardiac events, including CVD death and rehospitalisation for worsening HF. Univariate and multivariable adjustments were performed with Cox proportional-hazard regression analyses. The 25(OH)D concentration was obtained in 343 patients with a median value of 17·4 (interquartile range 12·6–23·4) ng/ml. There were 102 cardiac events, including forty-three deaths and fifty-nine rehospitalisations. Multivariate Cox hazard analysis found that the serum concentration 25(OH)D was independently associated with cardiac events (hazard ratio 0·93, 95 % CI 0·88, 0·97) and CVD mortality (hazard ratio 0·83; 95 % CI 0·77, 0·89) after adjustment for confounding factors. We divided the HF patients into four groups according to the 25(OH)D quartiles. Kaplan–Meier analysis found that the patients with lower serum 25(OH)D concentration had a higher risk of cardiac events or CVD mortality than those with high serum 25(OH)D concentration (log-rank test P < 0·001 and P = 0·032). Decreased serum concentrations of 25(OH)D were associated with cardiac prognosis and CVD mortality in a Chinese population with HF independent of other baseline HF markers.
Oxidative stress is closely related to metabolic disorders, which can lead to various diseases. Nuclear factor E2-related factor 2 (Nrf2) is a central regulator of oxidative stress. Sodium butyrate (NaB) has been shown to alleviate oxidative stress and insulin resistance, yet how Nrf2 is involved in the action of NaB remains unclear. In the present study, rats were rendered obese by feeding a high-fat diet for 9 weeks. NaB (300 mg/kg), which was gavaged every 2 d for 7 weeks, significantly alleviated high-fat diet-induced oxidative stress and insulin resistance. Additionally, the insulin signalling pathway in the liver was activated by NaB, associated with significant activation of Nrf2, superoxide dismutase and glutathione. Furthermore, hepatic up-regulation of Nrf2 in NaB-treated rats was associated with reduced protein content of histone deacetylase 1 and increased histone H3 acetyl K9 (H3K9Ac) modification on the Nrf2 promoter. The actions of NaB were completely abolished when Nrf2 was knocked down in vitro. Taken together, NaB acts as a histone deacetylase inhibitor to up-regulate Nrf2 expression with enhanced H3K9Ac modification on its promoter. NaB-induced Nrf2 activation stimulates transcription of downstream antioxidant enzymes, thus contributing to the amelioration of high-fat diet-induced oxidative stress and insulin resistance.
Image stitching is important for the perception and manipulation of undersea robots. In spite of a well-developed technique, it is still challenging for undersea images because of their inevitable appearance ambiguity caused by the limited light in the undersea environment, and local disturbance caused by moving objects, ocean current, etc. To get a clean and stable background panorama in the undersea environment, this paper proposes an undersea image-stitching method by introducing graph-based registration and blending procedures. Specifically, in the registration procedure, matching the features in each undersea image pair is formulated and solved by graph matching, to incorporate the structural information between features. In the blending procedure, an energy function on the indirect graph Markov random field is proposed, which takes both image consistency and neighboring consistency into consideration. Coincidentally, both graph matching and energy minimization can be mathematically formulated by integer quadratic programming problems with different constraints; the recently proposed graduated nonconvexity and concavity procedure is used to optimize both problems. Experiments on both synthetic images and real-world undersea images witness the effectiveness of the proposed method.
Personal protective equipment (PPE) is a necessary item in the period of unknown and high-risk emerging infectious disease. It is not only the necessary requirement of strict isolation, but also the last line of defense to protect medical staff.
Compare the differences between contaminated frequency and sites under two types of PPE doffing.
Recruited 56 health care workers (HCWs) who worked in clinical to follow the different PPE removal guidelines issued by the Chinese Center for Disease Control (CDC) and the World Health Organization (WHO) final resolution for preventing Ebola virus. Eight batches of HCWs were divided to conduct simulations of contaminated PPE removal using fluorescent lotion (Glitter Bug Potion, On Solution Pty Lt). Then we recorded the frequency and sites of contamination of personnel after removal of contaminated PPE by the method of visual observation.
According to China’s CDC process, the parts that are easily contaminated during PPE removal are: left hand and wrist (7 times), left calf (7 times), front chest center and left and right chest (6 times each) and left abdomen (5 times). Contaminated parts of the PPE process in accordance with the WHO process from high to low were: right hand and wrist (13 times), left hand and wrist (12 times), middle of the abdomen (10 times), left chest (9 times), and left abdomen (6 Times). There was no statistical difference between the two kinds of PPE piercing and removal (Z=1.177, P > 0. 05).
Under the guidance of the two processes recommended by China CDC and WHO, there was no significant difference in the frequency of pollution after removing PPE. It is speculated that the PPE recommendation processes issued by WHO and China CDC are effective for personal protection against fulminating infectious diseases.
Proper use of personal protective equipment (PPE) is essential when facing emerging infectious diseases. Proper training methods can promote the use of the PPE correctly.
To explore the effect of the training method of sequential operation training on medical staff to master PPE penetration and removal skills, and to study the memory attenuation after training.
Fifteen medical staff with no experience of PPE operation in a hospital were trained to wear PPE in accordance with WHO standards by illustration and sequential operation method. The training included 30 minutes of theoretical teaching and 60 minutes of practical exercises. At the end of the training and 1 week after the training, the training objects were evaluated for PPE operation. A 2.5 x 2.5 cm fluorescent agent was applied on 6 parts, such as hands, chest, abdomen, and knees, to simulate contamination. After taking the PPE off, the parts of the whole body and the inner layer of clothing that were fluorescently contaminated were recorded. The whole operation process was recorded by video to evaluate whether the operation was correct. The error rates of two operations and the contamination position and frequency were compared.
The error rate of the operating PPE after training was 18.6%, rising to 31.9% after 1 week (Z=16.0, P<0.05). After the training, the average number of contaminated PPE removal was 1.96±1.56, which rose to 2.96±2.03 one month later. The difference was statistically significant (Z=8.92, P<0.05). The main vulnerable sites are the wrist, chest, abdomen, and left calf.
Illustrative sequential operation training is an important means to improve the way for medical staff to wear PPE, but it must be completed more than once to ensure that medical staff can firmly master the skills of wearing and removing PPE.
Personal protective equipment (PPE) is a necessary item in the period of unknown and high risk emerging infectious disease. It is not only the necessary requirement of strict isolation but also the last line of defense to protect medical staff.
To determine the frequency and sites of contamination of personnel during the process of using Chinese PPE.
Recruit 56 health care workers (HCWs) who worked in front-line clinical to test PPE issued by the Chinese Center for Disease Control for preventing Ebola virus. Eight batches of HCWs were divided to conduct simulations of contaminated PPE removal using fluorescent lotion. Then the frequency and sites of contamination of personnel were recorded after removal of contaminated PPE. The method of visual observation was used to determine contamination.
The frequency of easily contaminated parts included: left hand and wrist (7 times), left calf (7 times), front chest center, left and right chest (6 times each), and left abdomen (5 times). Mistakes in the process of wearing PPE included: clothing touching the ground (20.00%), N95 air mask tightness not checked (13.33%), glove air-tightness not checked (4.44%), protective clothing zipper not checked (4.44%). Mistakes in doffing PPE included: clothes touching the ground or the inner surface is polluted (20.00%), the wrong method of removing N95 mask (14.44%), touching the pollution goggles mirror with hands (12.22%), incomplete washing steps, insufficient time and frequency of hand hygiene (11.11%).
It is necessary to carry out training on PPE donning and doffing for Chinese medical workers.
In inertial confinement fusion experiments that involve short-laser pulses such as fast ignition (FI), diagnosis of neutrons is usually very challenging because high-intensity γ rays generated by short-laser pulses would mask the much weaker neutron signal. In this paper, fast-response scintillators with low afterglow and gated microchannel plate photomultiplier tubes are combined to build neutron time-of-flight (nTOF) spectrometers for such experiments. Direct-drive implosion experiments of deuterium-gas-filled capsules were performed at the Shenguang-II Upgrade (SG-II-UP) laser facility to study the compressed fuel areal density (〈ρR〉) and evaluate the performance of such nTOF diagnostics. Two newly developed quenched liquid scintillator detectors and a gated ultrafast plastic scintillator detector were used to measure the secondary DT neutrons and primary DD neutrons, respectively. The secondary neutron signals were clearly discriminated from the γ rays from (n, γ) reactions, and the compressed fuel areal density obtained with the yield-ratio method agrees well with the simulations. Additionally, a small scintillator decay tail and a clear DD neutron signal were observed in an integrated FI experiment as a result of the low afterglow of the oxygen-quenched liquid scintillator.
Global Navigation Satellite System (GNSS) safety issues of have been of concern for some time. Spoofing attacks have received much attention as they can be difficult to detect and have the potential to cause disruption at best and major damage in extremis. To mitigate such threats, a spoofing detection method based on the consistency check of Doppler positioning fixes and pseudorange positioning fixes is proposed. The primary contributions of this paper include establishing a Generalised Likelihood Ratio Test (GLRT)-based statistical detection model for the introduced spoofing detection method and efficiently improving the accuracy of the Doppler positioning method as well as the performance of the detection approach by a modified α-filter-based Doppler smoothing technique. Theoretical performance of the proposed detection model is analysed. Monte Carlo simulations were also conducted to verify the theoretical analysis. Moreover, grounded on the developed test statistic and the optimised threshold, a consistency check module was specifically realised in both software defined and real-time GNSS receivers. Additionally, a Doppler smoothing technique was applied to the receivers. Spoofing attack experiments on both software defined and real-time platforms validated the effectiveness of the statistical spoofing detection model.
To investigate the protein-sparing effect of α-lipoic acid (LA), experimental fish (initial body weight: 18·99 (sd 1·82) g) were fed on a 0, 600 or 1200 mg/kg α-LA diet for 56 d, and hepatocytes were treated with 20 μm compound C, the inhibitor of AMP kinase α (AMPKα), treated for 30 min before α-LA treatment for 24 h. LA significantly decreased lipid content of the whole body and other tissues (P<0·05), and it also promoted protein deposition in vivo (P<0·05). Further, dietary LA significantly decreased the TAG content of serum and increased the NEFA content of serum (P<0·05); however, there were no significant differences among all groups in the hepatopancreas and muscle (P>0·05). Consistent with results from the experiment in vitro, LA activated phosphorylation of AMPKα and notably increased the protein content of adipose TAG lipase in intraperitoneal fat, hepatopancreas and muscle in vivo (P<0·05). Meanwhile, LA significantly up-regulated the mRNA expression of genes involved in fatty acid β-oxidation in the same three areas, and LA also obviously down-regulated the mRNA expression of genes involved in amino acid catabolism in muscle (P<0·05). Besides, it was observed that LA significantly activated the mammalian target of rapamycin (mTOR) pathway in muscle of experimental fish (P<0·05). LA could promote lipolysis and fatty acid β-oxidation via increasing energy supply from lipid catabolism, and then, it could economise on the protein from energy production to increase protein deposition in grass carp. Besides, LA might directly promote protein synthesis through activating the mTOR pathway.
Kaolinite can be used for many applications, including the underground storage of gases. Density functional theory was employed to investigate the adsorption of hydrogen molecules on the kaolinite (001) surface. The coverage dependence of the adsorption sites and energetics was studied systematically for a wide range of coverage, Θ (from 1/16 to 1 monolayer). The three-fold hollow site is the most stable, followed by the bridge, top-z and top sites. The adsorption energy of H2 decreased with increasing coverage, thus indicating the lower stability of surface adsorption due to the repulsion of neighbouring H2 molecules. The coverage has obvious effects on hydrogen adsorption. Other properties of the H2/kaolinite (001) system, including the lattice relaxation and changes of electronic density of states, were also studied and are discussed in detail.
We previously reported four heterozygous missense mutations of MYH7, KCNQ1, MYLK2, and TMEM70 in a single three-generation Chinese family with dual Long QT and hypertrophic cardiomyopathy phenotypes for the first time. However, the clinical course among the family members was various, and the potential myocardial dysfunction has not been investigated.
The objective of this study was to investigate the echocardiographic and electrocardiographic characteristics in a genetic positive Chinese family with hypertrophic cardiomyopathy and further to explore the association between myocardial dysfunction and electric activity, and the identified mutations.
A comprehensive echocardiogram – standard two-dimensional Doppler echocardiography and three-dimensional speckle tracking echocardiography – and electrocardiogram were obtained for members in this family.
As previously reported, four missense mutations – MYH7-H1717Q, KCNQ1-R190W, MYLK2-K324E, and TMEM70-I147T – were identified in this family. The MYH7-H1717Q mutation carriers had significantly increased left ventricular mass indices, elevated E/e’ ratio, deteriorated global longitudinal stain, but enhanced global circumferential and radial strain compared with those in non-mutation patients (all p<0.05). The KCNQ1-R190W carriers showed significantly prolonged QTc intervals, and the MYLK2-K324E mutation carriers showed inverted T-waves (both p<0.05). However, the TMEM70-I147T mutation carriers had similar echocardiography and electrocardiographic data as non-mutation patients.
Three of the identified four mutations had potential pathogenic effects in this family: MYH7-H1717Q was associated with increased left ventricular thickness, elevated left ventricular filling pressure, and altered myocardial deformation; KCNQ1-R190W and MYLK2-K324E mutations were correlated with electrocardiographic abnormalities reflected in long QT phenotype and inverted T-waves, respectively.
Introduction: To investigate the effects of paroxetine (PAR) on motor and cognitive function recovery in patients with non-depressed ischemic stroke (nD-AIS).
Methods: One hundred sixty-seven patients hospitalized for non-depressed acute ischemic stroke were selected and divided into treatment (T) and control (C) groups using a random number table. All patients received conventional secondary ischemic stroke prevention and rehabilitation training; patients in Group T additionally received treatment with PAR (10 mg/day during week 1 and 20 mg/day thereafter) for 3 months. The follow-up observation lasted 6 months. The Fugl–Meyer motor scale (FMMS), Montreal cognitive assessment (MoCA), and Hamilton depression scale (HAMD) were used on D0, D15, D90, and D180 (T0, 1, 2, and 3, respectively; D180 = 90 days after treatment cessation) after study initiation, and scores were compared between the groups.
Results: The FMMS and MoCA scores differed significantly between Groups T and C at T2 and T3 (p < .05); by contrast, these scores did not differ significantly between the groups at T1 (p > .05). Furthermore, the HAMD scores differed significantly between the two groups at T3 (p < .05), but not at T1 and T2 (p > .05).
Conclusions: PAR treatment may improve motor and cognitive function recovery in patients with nD-AIS. Moreover, PAR may reduce the occurrence of depression after stroke.
To produce pulses with good flat-top quality, pulse-forming lines (PFLs) have been widely used in the field of Tesla-type pulse generators. To shorten the physical length of the PFL, a double-width PFL (DWPFL) is proposed that doubles the output pulse width while maintaining flat-top quality. A repetitively 10 GW Tesla-type long-pulse generator producing pulses with flat-top width of about 110 ns was developed with a coaxial DWPFL to produce high-current electron beams. Electron beams of about 10 GW with flat-top widths of about 110 ns were obtained on a planar vacuum diode load. With this pulse generator and a C-band high-power microwave system, microwaves of ~2.2 GW power and full-width at half-maximum of 101 ns were generated. The experiment demonstrates the feasibility and ideal output waveform quality of the DWPFL.
This study examined the mediating effects of future social expectations and interpersonal distrust on the relationship between individual relative deprivation and intention to rebel. Data were gathered from 807 people from multiple occupational backgrounds in a municipality in southwest China. Structural equation modelling showed that individual relative deprivation predicted intention to rebel directly and also that it predicted intention to rebel indirectly via negative future social expectations, interpersonal distrust, and a chain mediating effect of negative future social expectations and interpersonal distrust. These results highlight the importance of the associations between future social expectations and interpersonal distrust with intention to rebel in people who report relative deprivation. The findings also indicate that prevention and intervention programs related to relative deprivation and intention to rebel in China are worthy of further research.
Colistin, a peptide antibiotic belonging to the polymyxin family, is one of the last effective drugs for the treatment of multidrug resistant Gram-negative infections. Recent discovery of a novel mobile colistin resistance gene, mcr-1, from people and food animals has caused a significant public health concern and drawn worldwide attention. Extensive usage of colistin in food animals has been proposed as a major driving force for the emergence and transmission of mcr-1; thus, there is a worldwide trend to limit colistin usage in animal production. However, despite lack of colistin usage in food animals in the USA, mcr-1-positive Escherichia coli isolates were still isolated from swine. In this paper, we provided an overview of colistin usage and epidemiology of mcr-1 in food animals, and summarized the current status of mechanistic and evolutionary studies of the plasmid-mediated colistin resistance. Based on published information, we further discussed several non-colistin usage risk factors that may contribute to the persistence, transmission, and emergence of colistin resistance in an animal production system. Filling the knowledge gaps identified in this review is critical for risk assessment and risk management of colistin resistance, which will facilitate proactive and effective strategies to mitigate colistin resistance in future animal production systems.
A parallel, high-order direct Discontinuous Galerkin (DDG) method has been developed for solving the three dimensional compressible Navier-Stokes equations on 3D hybrid grids. The most distinguishing and attractive feature of DDG method lies in its simplicity in formulation and efficiency in computational cost. The formulation of the DDG discretization for 3D Navier-Stokes equations is detailed studied and the definition of characteristic length is also carefully examined and evaluated based on 3D hybrid grids. Accuracy studies are performed to numerically verify the order of accuracy using flow problems with analytical solutions. The capability in handling curved boundary geometry is also demonstrated. Furthermore, an SPMD (single program, multiple data) programming paradigm based on MPI is proposed to achieve parallelism. The numerical results obtained indicate that the DDG method can achieve the designed order of accuracy and is able to deliver comparable results as the widely used BR2 scheme, clearly demonstrating that the DDG method provides an attractive alternative for solving the 3D compressible Navier-Stokes equations.
The earliest fossil record of animal biomineralization occurs in the latest Ediacaran Period (c. 550 Ma). Cloudina and Sinotubulites are two important tubular taxa among these earliest skeletal fossils. The evolutionary fate of Cloudina-type fossils across the Ediacaran–Cambrian transition, however, remains poorly understood. Here we report a multi-layered tubular microfossil Feiyanella manica gen. et sp. nov. from a phosphorite interval of the lowest Cambrian Kuanchuanpu Formation, southern Shaanxi Province, South China. This newly discovered fossil is a conical tube with a ‘funnel-in-funnel’ construction, showing profound morphological similarities to Cloudina and Conotubus. On the other hand, the outer few layers, and particularly the outermost layer, of Feiyanella tubes are regularly to irregularly corrugated, a feature strikingly similar to the variably folded/wrinkled tube walls of Sinotubulites. The Feiyanella tubes additionally exhibit two orders of dichotomous branching, similar to branching structures reported occasionally in Cloudina and possibly indicative of asexual reproduction. Owing to broad similarities in tube morphology, tube wall construction and features presumably indicative of asexual reproduction, Cloudina, Conotubus, Sinotubulites and the here described Feiyanella may thus constitute a monophyletic group traversing the Ediacaran–Cambrian boundary. The tube construction and palaeoecological strategy of Feiyanella putatively indicate evolutionary continuity in morphology and palaeoecology of benthic metazoan communities across the Ediacaran–Cambrian transition.
Volume-preserving algorithms (VPAs) for the charged particles dynamics is preferred because of their long-term accuracy and conservativeness for phase space volume. Lie algebra and the Baker-Campbell-Hausdorff (BCH) formula can be used as a fundamental theoretical tool to construct VPAs. Using the Lie algebra structure of vector fields, we split the volume-preserving vector field for charged particle dynamics into three volume-preserving parts (sub-algebras), and find the corresponding Lie subgroups. Proper combinations of these subgroups generate volume preserving, second order approximations of the original solution group, and thus second order VPAs. The developed VPAs also show their significant effectiveness in conserving phase-space volume exactly and bounding energy error over long-term simulations.
In this study, the effects of HA combined with NPK fertilizer (HANPK) on root growth and leaf quality of tobacco plants were investigated in tobacco fields. Results indicated that the application of HA alone did not enhance the growth of tobacco obviously, while HANPK increased tobacco biomass by 36.9% and stimulated the growth of lateral roots significantly. The number of the second-order lateral roots was increased by 89.3% compared with the control. Furthermore, HANPK raised the ratio of root biomass in 0–20 cm soil layer over the whole soil layer and increased the proportion of fine roots over the total roots. Tobacco leaf yield, output value, and benefit of HANPK were 12.2%, 29.4% and 35.5% higher than those of the control, respectively. The above results suggest that the combined application of HA and NPK chemical fertilizer is an economical pattern for improving tobacco growth.