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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.
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.
This paper is concerned with the global dynamics and spreading speeds of a partially degenerate non-local dispersal system with monostable nonlinearity in periodic habitats. We first obtain the existence of the principal eigenvalue for a periodic eigenvalue problem with partially degenerate non-local dispersal. Then we study the coexistence and extinction dynamics. Finally, the existence and characterization of spreading speeds are considered. In particular, we show that the spreading speed is linearly determinate. Overall, we extend the existing results on global dynamics and spreading speeds for the degenerate reaction–diffusion system to the degenerate non-local dispersal case. The extension is non-trivial and meaningful.
Monosized spherical Cu–20% Sn (wt%) alloy particles with diameter ranging from 70.6 to 334.0 μm were prepared by the pulsated orifice ejection method (termed “POEM”). Fully dense without pores and bulk inclusions, the cross-sectional micrographs of the spherical alloy particles indicate an even distribution of Cu and Sn. These spherical Cu–Sn alloy particles exhibit a good spherical shape and a narrow size distribution, suggesting that the liquid Cu–Sn alloy can completely break the balance between the surface tension and the liquid static pressure in the crucible micropores and accurately control the volume of the droplets. Furthermore, the cooling rate of spherical Cu–20% Sn alloy particles is estimated by a Newton’s cooling model. The cooling rate of the Cu–20% Sn alloy particle decreases gradually with the particle diameter increasing. Smaller particles have higher cooling rates and when the particle diameter is less than 70 μm, the cooling rate of particles can reach more than 3.3 × 104 K/s. The secondary dendrite arm spacing has strong dependence on particle diameter which increases gradually with the increase of particle diameter. The results demonstrate that POEM is an effective route for fabrication of high-quality monosized Cu–20% Sn alloy particles.
A coaxial-output rolled strip pulse-forming line (RSPFL) with a dry structure is researched for the purpose of miniaturization and all-solid state of pulse-forming lines (PFL). The coaxial-output RSPFL consists of a coaxial-output electrode (COE) and a rolled strip line (RSL). The COE is characterized by quasi-coaxial structure, making the output pulse propagate along the axial direction with a small output inductance. The RSL is rolled on the COE, whose transmission characteristics are analyzed theoretically. It shows that the RSL can be regarded as a planar strip line when the rolling radius of the strip line is larger than 60 times of the thickness of the insulation dielectric layer of RSL. CST modeling was carried out to simulate the discharging characteristic of the coaxial-output RSPFL. It shows that the coaxial-output RSPFL can deliver a discharging pulse with a rise time <6 ns when the impedance of the RSL matches that of the COE, which confirms the theoretical analysis. A prototype of the coaxial-output RSPFL was developed. A 49-kV discharging pulse on a matched load was achieved when it was charged to 100 kV. The discharging waveform has a pulse width of 32 ns, with a rise time of 6 ns, which is consistent with the simulation waveform. An energy-storage density of 1.9 J/L was realized in the coaxial-output RSPFL. By the method of multi-stage connection in series, a much higher output voltage is convenient to be obtained.
Bipolar disorder is a highly heritable polygenic disorder. Recent
enrichment analyses suggest that there may be true risk variants for
bipolar disorder in the expression quantitative trait loci (eQTL) in the
We sought to assess the impact of eQTL variants on bipolar disorder risk
by combining data from both bipolar disorder genome-wide association
studies (GWAS) and brain eQTL.
To detect single nucleotide polymorphisms (SNPs) that influence
expression levels of genes associated with bipolar disorder, we jointly
analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls)
and a genome-wide brain (cortical) eQTL (193 healthy controls) using a
Bayesian statistical method, with independent follow-up replications. The
identified risk SNP was then further tested for association with
hippocampal volume (n = 5775) and cognitive performance
(n = 342) among healthy individuals.
Integrative analysis revealed a significant association between a brain
eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes
factor = 5.48; bipolar disorder P =
5.85×10–5). Follow-up studies across multiple independent
samples confirmed the association of the risk SNP (rs6088662) with gene
expression and bipolar disorder susceptibility (P =
3.54×10–8). Further exploratory analysis revealed that
rs6088662 is also associated with hippocampal volume and cognitive
performance in healthy individuals.
Our findings suggest that 20q11.22 is likely a risk region for bipolar
disorder; they also highlight the informative value of integrating
functional annotation of genetic variants for gene expression in
advancing our understanding of the biological basis underlying complex
disorders, such as bipolar disorder.
To examine the vitamin D status, SNP of the vitamin D receptor gene (VDR) and the effects of vitamin D supplementation on parathyroid hormone and insulin secretion in adult males with obesity or normal weight in a subtropical Chinese city.
An intervention trial.
Shenzhen City, Guangdong Province, China.
From a cross-sectional survey conducted from June to July, eighty-two normal-weight and ninety-nine obese males (18–69 years) were screened to analyse their vitamin D status and for five SNP of VDR. From these individuals, in the same season of a different year, obese and normal-weight male volunteers (twenty-one per group) were included for an intervention trial with oral vitamin D supplementation at 1250 µg/week for 8 weeks.
For the survey, there was no significant difference (P>0·05) in baseline circulating 25-hydroxyvitamin D concentrations or in the percentages of participants in different categories of vitamin D status between the two groups. The VDR SNP, rs3782905, was significantly associated with obesity (P=0·043), but none of the examined SNP were correlated with serum 25-hydroxyvitamin D when adjusted for age, BMI and study group. After vitamin D supplementation, serum 25-hydroxyvitamin D concentration, hypersecretions of parathyroid hormone and insulin, and insulin resistance in the obese were changed beneficially (P<0·05); however, the increase in serum 25-hydroxyvitamin D was less than that of the normal-weight men.
For obese and normal-weight men of subtropical China, the summer baseline vitamin D status was similar. However, oral vitamin D supplementation revealed a decreased bioavailability of vitamin D in obese men and ameliorated their hypersecretion of parathyroid hormone and insulin resistance.
Low-temperature stress is an important limiting factor to tobacco growth in early spring of south China. In this study, a low-temperature-resistant agent (LTRA) was employed to examine its ameliorating effect on the inhibition of tobacco growth triggered by low-temperature stress. Results indicated that low-temperature stress of 12 °C for 6 days reduced root number and biomass of tobacco seedling by 27.4% and 24.1%, while treatment with LTRA could recover the inhibitory effect of low-temperature stress on tobacco growth significantly. The content of ascorbic acid and the activities of superoxide dismutase and catalase at low-temperature stress were 65.2%, 53.5% and 32.1% of those at normal temperature condition (26 °C), while the corresponding values with LTRA treatment were 89.2%, 88.9% and 74.2%, suggesting that LTRA treatment could enhance the activity of antioxidant enzyme and the synthesis of antioxidant compounds. Low-temperature stress increased the membrane permeability by 84.8%, while LTRA treatment recovered it by 77.4%. Furthermore, LTRA treatment contributed to increase chlorophyll synthesis and maintain the integrity of tobacco leaf structure. Effective component analysis indicated that the complex of ammonium calcium nitrate and glycine betaine was the main effective component of LTRA in maintaining membrane integrity. Its effective concentration was 1.0 g L−1. The above results suggested that LTRA could enhance the synthesis of chlorophyll, activate the activity of antioxidant enzyme, maintain the integrity of cell membrane, and thus elevate the tolerance of tobacco seedlings to low-temperature stress.
the goal of this study was to identify important prognostic variables affecting placement of a percutaneous endoscopic gastrostomy (Peg) tube after acute stroke.
We retrospectively reviewed our patient database to identify acute ischemic stroke patients who placed Peg or nasogastric tube (Ngt) tube, but were free of other confounding conditions affecting swallowing. A total of 340 patients were involved in our study. We assessed the influence of age, National Institutes of Health stroke scale (NIHss) score, infarct volume, stroke subtype based on the toAst criteria, swallowing disorders, bilateral lesions in cerebrum and length of stay (los) in a logistic regression analysis.
In univariate analysis, age (p=0.048), NIHss score (p<0.0001), lesion volume (p<0.0001), los (p<0.0001), stroke location (p=0.045), and swallowing disorders (p<0.0001) were found to be the primary predictors of placing Peg. the presence of lesions in bilateral cerebral was included in the final model based on clinical considerations. After multivariate adjustment, only NIHss score (odds ratio [oR], 4.055; 95% confidence interval [CI], 2.398-6.857; p=0.0001), lesion volume (oR, 1.69; 95%CI, 1.09–4.39; p=0.014), swallowing disorders (oR, 1.151; 95% CI, 1.02-1.294; p=0.047), los (oR, 0.955; 95% CI, 0.914-0.998; p=0.0415) and bilateral lesions (oR, 2.8; 95% CI, 1.666-4.705; p=0.0001) remained significant.
our data shows that NIHss score, lesion volume, swallowing disorders, los and bilateral lesions in cerebrum can predict the requiring of Peg tube insertion in patients after stroke.
Let 𝒯n(F) denote the monoid of all upper triangular n×n matrices over a finite field F. It has been shown by Volkov and Goldberg that 𝒯n(F) is nonfinitely based if ∣F∣>2 and n≥4, but the cases when ∣F∣>2 and n=2,3 or when ∣F∣=2 have remained open. In this paper, it is shown that the monoid 𝒯2 (F) is finitely based when ∣F∣=2 , and a finite identity basis for it is given. Moreover, all maximal subvarieties of the variety generated by 𝒯2 (F) with ∣F∣=2 are determined.
The mouse sperm genome is resistant to in vitro heat treatment, and embryos derived from heated sperm can support full-term embryonic development, but the blastocyst rate and implantation rate are lower compared to embryos derived from fresh sperm. In the present study, the patterns of DNA methylation, histone H4K12 (ACH4K12) acetylation, H3K9 trimethylation (H3K9-TriM), and H3K27 trimethylation (H3K27-TriM) in preimplantation embryos derived from 65°C-heated sperm were investigated. Although no evident changes in global DNA methyaltion, histone H4K12 (ACH4K12) acetylation, and H3K9 trimethylation (H3K9-TriM) were found, significantly lower levels of H3K27-TriM, which was thought to be one of the reasons for low efficiency of mouse cloning, were found in the inner cell mass of heated-sperm derived blastocysts. Thus, defective modification of H3K27-TriM might contribute to compromised development of embryos derived from heated sperm.
Ultrashort electron bunch trains can be used for plasma wake field acceleration (PWFA) to overcome the limit of transformer ratio of a single electron bunch, or high-power terahertz (Thz) radiation production by various radiation mechanisms. Basic facility for high-power THz radiation development based on ultrashort electron beam has been set up at accelerator lab of TUB. Using birefringent crystal serials, ultraviolet (UV) pulse shaping for photocathode radio frequency gun to produce THz-repetition-rate pulse train was realized. Driven by such pulses, ultrashort electron bunch train with picosecond (ps) spacing was obtained for THz production. Measurement of the stacked UV pulse trains was done by difference frequency generation (DFG), and the measured group velocity mismatch of α-BBO crystal at 266.7-nm wavelength was 0.8 ps/mm. This method may also be applied to form ramped electron bunch trains for PWFA.
Signal-In-Space Error (SISE) is important for the system integrity of GNSS. Real-time monitoring SISE has been one of the effective solutions used for improving GNSS system-level integrity. As one of the typical solutions, the Galileo integrity concept uses Signal-In-Space Accuracy (SISA) and Signal-In-Space Monitoring Accuracy (SISMA) respectively to transmit the quality of SIS and the integrity alarming information to users. As an important component of the Galileo Integrity Concept, Worst User Location (WUL) is of great importance for the computation of SISA and SISMA. An improved WUL algorithm based on a geometrical model is given in this paper, which needs no iterative search and is simple when compared with the existing models. The WUL accuracy requirement is discussed based on an analysis of the magnitude of the orbit errors and SIS ranging resolution and error. The conclusion is that, considering the metre-level orbital error observed in the orbit determination process, as long as the orientation error of the WUL is less than three degrees, the projection error of SISE can be kept to centimetre levels. This will satisfy the requirements of most users. The algorithm is further optimised to omit the non-linear iterative parts based on the above assumption. The optimisation reduces computation load and enhances the real-time capability. GPS raw measurements are used to validate the correctness and reliability of the algorithms.
Chemical bath deposition (CBD) techniques for the growth of CdS polycrystalline thin films are now well developed. However, there usually appear different structures, grain sizes and energy gaps in CdS polycrystalline films by CBD, which implies that the influence of growth process on the structures and properties of CBD CdS thin films must be considered. In this paper, the optical, compositional and structural properties of CBD CdS thin films in the reaction process have been studied by XRD, AFM, XPS and optical transmission spectra measurements. The results can be explained using atomic mechanism and lattice transition in the CdS thin films.
The expression of the YUCAA1 gene and the amount of endogenous indole acetic acid (IAA) in rice (Oryza sativa subsp. japonica) plants and rice suspension cells infected by Rice stripe virus (RSV) were investigated by real-time reverse transcriptase–polymerase chain reaction (RT-PCR) and high-performance liquid chromatography, respectively. The results showed that the expression of the YUCAA1 gene and the amount of endogenous IAA increased at various times (16, 32, 48 and 64 h) after infection of rice suspension cells by RSV. In rice plants infected with RSV, the expression of the YUCAA1 gene and the amount of endogenous IAA increased, in comparison with healthy rice plants, at 4–8 days after infection, and decreased at 12 and 16 days. These results indicated that RSV infection could regulate auxin biosynthesis in rice. Additionally, the expression of the RSV gene CP increased 2.9 times in rice plants after they were treated with a KPSC buffer to deplete the endogenous auxins, and decreased 45% after treatment with 30 μmol/l IAA. All of these results suggest that auxin may play a role in RSV replication in rice plants.
The strategies of repair of tetralogy of Fallot change with the age of patients. In children older than 4 years and adults, the optimal strategy may be to use different method of reconstruction of the right ventricular outflow tract from those followed in younger children, so as to avoid, or reduce, the pulmonary insufficiency that is increasingly known to compromise right ventricular function.
From April, 2001, through May, 2008, we undertook complete repair in 312 patients, 180 male and 132 female, with a mean age of 11.3 years ±0.4 years, and a range from 4 to 48 years, with typical clinical and morphological features of tetralogy of Fallot, including 42 patients with the ventriculo-arterial connection of double outlet right ventricle. The operation was performed under moderate hypothermia using blood cardioplegia. The ventricular septal defect was closed with a Dacron patch. When it was considered necessary to resect the musculature within the right ventricular outflow tract, or perform pulmonary valvotomy, we sought to preserve the function of the pulmonary valve by protecting as far as possible the native leaflets, or creating a folded monocusp of autologous pericardium.
The repair was achieved completely through right atrium in 192, through the right ventricular outflow tract in 83, and through the right atrium, the outflow tract, and the pulmonary trunk in 36 patients. A transjunctional patch was inserted in 169 patients, non-valved in all but 9. There were no differences regarding the periods of aortic cross-clamping or cardiopulmonary bypass. Of the patients, 5 died (1.6%), with no influence noted for the transjunctional patch. Of those having a non-valved patch inserted, three-tenths had pulmonary regurgitation of various degree, while those having a valved patch had minimal pulmonary insufficiency and good right ventricular function postoperatively, this being maintained after follow-up of 8 to 24-months.
Based on our experience, we suggest that the current strategy of repair of tetralogy of Fallot in older children and adults should be based on minimizing the insertion of transjunctional patches, this being indicated only in those with very small ventriculo-pulmonary junctions. If such a patch is necessary, then steps should be taken to preserve the function of the pulmonary valve.
We investigated whether the hypolipidaemic effect of fenofibrate and fasting observed in most omnivorous mammals may also apply to herbivorous fish. Grass carp (Ctenopharyngodon idella) fed a high-fat (8 %) diet exhibited a marked increase in blood lipids and body fat after 6 weeks. They were then treated with fenofibrate (100 mg/kg body weight) in the same high-fat diet for 2 weeks, followed by fasting for 1 week. Plasma lipid concentration, body fat amount, fatty acid composition, plasma thiobarbituric acid-reactive substances and some parameters related to hepatic fatty acid oxidation were measured, and liver samples were stained for histological examination. Fenofibrate treatment decreased TAG and cholesterol concentrations in plasma, total lipids of the whole body and liver, and EPA and DHA contents in tissues. Further, a mobilisation of mesenteric fat concomitant with an increase in hepatic peroxisomal fatty acid oxidation and lipid peroxidation was observed. Compared with fenofibrate treatment, fasting decreased body weight and plasma TAG, but not plasma cholesterol. It also reduced the fat content of the whole body and increased the EPA and DHA contents in the liver and other tissues. Fatty acid oxidation was stimulated by fasting in mitochondria, but not in peroxisomes. These data suggest that fenofibrate and fasting regulate the lipid metabolism in grass carp through different metabolic pathways. The grass carp is moderately responsive to a fibrate derivative in comparison with the well-known excess responsiveness of the rat model, and so it could be used for the study of lipid abnormalities as a herbivorous model.
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.
Unbiased or upper limit estimates of the rate (U) of genomic mutations to mildly deleterious alleles are crucial in genetic and conservation studies and in human health care. However, only a few estimates of the lower bounds of U are available. We present a fairly robust estimation that yields an upper limit of U and a nearly unbiased estimate of the per generation fitness decline due to new deleterious mutations. We applied the approach to three species of the freshwater microcrustacean Daphnia and revealed that the upper limit of U for egg survivorship is 0·73 (SD=0·30) in 14 D. pulicaria populations. For the first four clutches, per generation decline in fecundity due to deleterious mutations ranged from 2·2% to 7·8% in 20 D. pulex populations and from 1·1% to 5·1% in 8 D. obtusa populations. These results indicate the mutation pressure is high in natural Daphnia populations. The approach investigated here provides a potential way to quickly and conveniently characterize U and per generation effects of deleterious genomic mutations on fitness or its important components such as fecundity.
High-fat diets may have favourable effects on growth of some carnivorous fish because of the protein-sparing effect of lipids, but high-fat diets also exert some negative impacts on flesh quality. The goal of the study was therefore to determine the effects of fat-enriched diets in juvenile grass carp (Ctenopharyngodon idella) as a typical herbivorous fish on growth and possible lipid metabolism alterations. Three isonitrogenous diets containing 2, 6 or 10% of a mixture of lard, maize oil and fish oil (1:1:1, by weight) were applied to fish for 8 weeks in a recirculation system. Data show that feeding diets with increasing lipid levels resulted in lowered feed intake, decreased growth and feed efficiency, and increased mesenteric fat tissue weight. Concomitantly, alteration of lipoprotein synthesis and greater level of lipid peroxidation were apparent in blood. In liver, muscle and mesenteric fat tissue, the percentages of α-linolenic acid and DHA were significantly increased or tended to increase with higher dietary lipid levels. Biochemical activity measurements performed on liver showed that, with the increase in dietary lipid level, there was a decrease in both mitochondrial and peroxisomal fatty acid oxidation capacities, which might contribute, at least in part, to the specific accumulation of α-linolenic acid and DHA into cells more active in membrane building. On the whole, grass carp have difficulty in energetically utilising excess dietary fat, especially when enriched in n−3 PUFA that are susceptible to peroxidation.