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Fossil feathers have greatly improved our understanding of the evolutionary transition from non-avian dinosaurs to birds and the evolution of feathers, and may be the only evidence for their source animals in the fossil record. Hot spring environments have been demonstrated to be conducive to the preservation of fossils, but internal silicification of feathers was not observed in the only avian carcass so far discovered in ancient hot spring deposits. To determine whether feathers can be internally silicified, here we analyse feathers sampled from a modern hot spring vent pool – Champagne Pool – in New Zealand. Our results of scanning electron microscopy (SEM)-energy dispersive X-ray spectrometry elemental mapping show that the sampled feathers are silicified to different degrees, and one of them is pervasively silicified. SEM observations show that feathers can be silicified at the cellular level. Degradation is involved in the silicification of feathers, as indicated by the reduction of the abundance of carbon and the loss of keratin fibrils. Our findings suggest that ancient deposits of hot spring vent pools are promising targets in search for fossil feathers.
Sarcopenic obesity is regarded as a risk factor for the progression and development of non-alcoholic fatty liver disease (NAFLD). Since male sex is a risk factor for NAFLD and skeletal muscle mass markedly varies between the sexes, we examined whether sex influences the association between appendicular skeletal muscle mass to visceral fat area ratio (SVR), that is, an index of skeletal muscle mass combined with abdominal obesity, and the histological severity of NAFLD. The SVR was measured by bioelectrical impedance in a cohort of 613 (M/F = 443/170) Chinese middle-aged individuals with biopsy-proven NAFLD. Multivariable logistic regression and subgroup analyses were used to test the association between SVR and the severity of NAFLD (i.e. non-alcoholic steatohepatitis (NASH) or NASH with the presence of any stage of liver fibrosis). NASH was identified by a NAFLD activity score ≥5, with a minimum score of 1 for each of its categories. The presence of fibrosis was classified as having a histological stage ≥1. The SVR was inversely associated with NASH in men (adjusted OR 0·62; 95 % CI 0·42, 0·92, P = 0·017 for NASH, adjusted OR 0·65; 95 % CI 0·43, 0·99, P = 0·043 for NASH with the presence of fibrosis), but not in women (1·47 (95 % CI 0·76, 2·83), P = 0·25 for NASH, and 1·45 (95 % CI 0·74, 2·83), P = 0·28 for NASH with the presence of fibrosis). There was a significant interaction for sex and SVR (Pinteraction = 0·017 for NASH and Pinteraction = 0·033 for NASH with the presence of fibrosis). Our findings show that lower skeletal muscle mass combined with abdominal obesity is strongly associated with the presence of NASH only in men.
Characteristics of particle clustering in a particle-laden turbulent boundary layer at a moderate frictional Reynolds number ($Re_\tau =5500$) are experimentally investigated based on Voronoï analysis. High-inertia sand grains with a large viscous-time-based Stokes number, i.e. $St_p=10^2 - 10^3$, are used as the dispersed phase. The bulk particle volume fraction is $\varPhi _V\sim O(10^{-5})$. Two-dimensional velocity fields of the fluid and particle phases in the streamwise–wall-normal plane are simultaneously measured via particle image/tracking velocimetry. Under the net sedimentation condition, a self-similarity of the geometries of particle clusters is clearly seen in the log layer. This can be characterized by the $-5/3$ power law of the probability density functions of the particle cluster areas and the $y$-scaling of their first- and second-order moments. Considering the self-similarity of wall-attached structures in the attached eddy hypothesis, we propose a conceptual model in which a large proportion of particle clusters prefer to reside on the back ridges of low-momentum attached $u$-structures due to the high-strain effect caused by converging sweep–ejection events. Such a scenario can be partly evidenced by the conditional streamwise spectra of the streamwise and wall-normal fluid-phase velocity components being conditioned inside cluster-occupied regions, which present a distinct $y$-scaling in the log layer. Furthermore, the fluid-phase sweep and ejection events inside particle clusters are observed to be weaker than the cases outside cluster-occupied regions, and the local rate of strain inside cluster-occupied regions is relatively higher than in all unconditional statistics. Finally, conditional statistics reveal that those sand grains with relatively small slip velocities are prone to be captured by low-momentum turbulent motions to form particle clusters.
The FNDC5 gene encodes the fibronectin type III domain-containing protein 5 that is a membrane protein mainly expressed in skeletal muscle, and the FNDC5 rs3480 polymorphism may be associated with liver disease severity in non-alcoholic fatty liver disease (NAFLD). We investigated the influence of the FNDC5 rs3480 polymorphism on the relationship between sarcopenia and the histological severity of NAFLD. A total of 370 adult individuals with biopsy-proven NAFLD were studied. The association between the key exposure sarcopenia and the outcome liver histological severity was investigated by binary logistic regression. Stratified analyses were undertaken to examine the impact of FNDC5 rs3480 polymorphism on the association between sarcopenia and the severity of NAFLD histology. Patients with sarcopenia had more severe histological grades of steatosis and a higher prevalence of significant fibrosis and definite non-alcoholic steatohepatitis than those without sarcopenia. There was a significant association between sarcopenia and significant fibrosis (adjusted OR 2·79, 95 % CI 1·31, 5·95, P = 0·008), independent of established risk factors and potential confounders. Among patients with sarcopenia, significant fibrosis occurred more frequently in the rs3480 AA genotype carriers than in those carrying the FNDC5 rs3480 G genotype (43·8 v. 17·2 %, P = 0·031). In the association between sarcopenia and liver fibrosis, there was a significant interaction between the FNDC5 genotype and sarcopenia status (P value for interaction = 0·006). Sarcopenia is independently associated with significant liver fibrosis, and the FNDC5 rs3480 G variant influences the association between sarcopenia and liver fibrosis in patients with biopsy-proven NAFLD.
Although higher dietary intake of MUFA has been shown to improve glycaemic control and lipid profiles, whether MUFA consumption from different sources is linked to the development of type 2 diabetes (T2D) remains unclear. We aimed to prospectively assess the associations of plant-derived MUFA (P-MUFA) and animal-derived MUFA (A-MUFA) intakes with T2D risk in a nationwide oriental cohort. Overall, 15 022 Chinese adults, aged ≥20 years, from the China Health and Nutrition Survey (CHNS 1997–2011) were prospectively followed up for a median of 14 years. Consumption of MUFA from plant and animal sources was assessed using 3-d 24-h recalls in each survey, and the cumulative average of intake was calculated. Multivariable-adjusted Cox models were constructed to estimate the hazard ratios (HR) of T2D according to quartiles of MUFA intake. P-MUFA were mainly consumed from cooked vegetable oils, fried bread sticks and rice, while A-MUFA were mainly consumed from pork, lard and eggs. Intake of P-MUFA was associated with a higher risk of T2D (HRQ4 v. Q1 1·50 (95 % CI 1·18, 1·90); Ptrend = 0·0013), whereas A-MUFA showed no significant association (HRQ4 v. Q1 0·84 (95 % CI 0·59, 1·20); Ptrend = 0·30). When further considering the cooking method of food sources, consumption of P-MUFA from fried foods was positively associated with T2D risk (HRQ4 v. Q1 1·60 (95 % CI 1·26, 2·02); Ptrend = 0·0006), whereas non-fried P-MUFA were not associated. Intake of MUFA from fried plant-based foods may elevate T2D risk among the Chinese population.
An experiment was conducted to determine the effects of supplementing different amounts of daidzein in a diet on the growth performance, blood biochemical parameters and meat quality of finishing beef cattle. Thirty finishing Xianan steers were distributed in three groups equilibrated by weight and fed three different dietary treatments (concentrate ratio = 80%): (1) control; (2) 500 mg/kg daidzein and (3) 1000 mg/kg daidzein, respectively. Steers were slaughtered after an 80-day feeding trial. Results showed that daidzein supplementation had no effect on the final body weight, average daily gain and feed conversion rate of steers. Steers fed with 1000 mg/kg daidzein had greater dry matter intake than those fed with control diets. Compared with the control group, the 1000 mg/kg daidzein group had a higher fat thickness, lower shear force and lightness. The pH, drip loss, cooking loss, redness (a*), yellowness (b*), moisture, ash, crude protein and intramuscular fat of the Longissimus dorsi muscle were unaffected by daidzein supplementation. Compared with the control group, the 1000 mg/kg daidzein group significantly increased the serum concentrations of insulin, free fatty acid and Glutamic-pyruvic transaminase. The 500 mg/kg daidzein group significantly increased the serum concentration of tetraiodothyronine compared with the control group. Supplemental daidzein did not affect the blood antioxidant ability and blood immune parameters in serum. In conclusion, daidzein supplementation above 500 mg/day modifies feed intake and metabolic and hormonal profile, with positive and negative effects on meat quality.
Low urinary iodine concentration (UIC) is associated with dyslipidaemia in adults but is not well characterised in adolescents. Because dyslipidaemia is a cardiovascular risk factor, identifying such an association in adolescents would allow for the prescription of appropriate measures to maintain cardiovascular health. The present study addresses this question using data in the 2001–2012 National Health and Nutrition Examination Survey for 1692 adolescents aged 12–19 years. Primary outcomes were UIC, cardiometabolic risk factors and dyslipidaemia. Data for subjects categorised by low and normal UIC and by sex were analysed by univariate and multivariate logistic regression. Treating UIC as the independent variable, physical activity level, apoB and lipid profiles differed significantly between subjects with low and normal UIC. Subjects with low UIC had a significantly greater risk of elevated total cholesterol (TC) (95 % CI 1·37, 2·81), elevated non-HDL (95 % CI 1·33, 2·76) and elevated LDL (95 % CI 1·83, 4·19) compared with those with normal UIC. Treating UIC as a dependent variable, the risk of low UIC was significantly greater in those with higher apoB (95 % CI 1·52, 19·08), elevated TC (≥4·4mmol/l) (95 % CI 1·37, 2·81) and elevated non-HDL (≥3·11mmol/l) (95 % CI 1·33, 2·76) than in those with normal UIC. These results show that male and female adolescents with low UIC tend to be at greater risk of dyslipidaemia and abnormal cardiometabolic biomarkers, though the specific abnormal parameters differed between sexes. These results may help to identify youth who would benefit from interventions to improve their cardiometabolic risk.
As the co-enzyme of pyruvate dehydrogenase and α-ketoglutarate dehydrogenase, thiamine plays a critical role in carbohydrate metabolism in dairy cows. Apart from feedstuff, microbial thiamine synthesis in the rumen is the main source for dairy cows. However, the amount of ruminal thiamine synthesis, which is influenced by dietary N levels and forage to concentrate ratio, varies greatly. Notably, when dairy cows are overfed high-grain diets, subacute ruminal acidosis (SARA) occurs and results in thiamine deficiency. Thiamine deficiency is characterised by decreased ruminal and blood thiamine concentrations and an increased blood thiamine pyrophosphate effect to >45 %. Thiamine deficiency caused by SARA is mainly related to the increased thiamine requirement during high grain feeding, decreased bacterial thiamine synthesis in the rumen, increased thiamine degradation by thiaminase, and decreased thiamine absorption by transporters. Interestingly, thiamine deficiency can be reversed by exogenous thiamine supplementation in the diet. Besides, thiamine supplementation has beneficial effects in dairy cows, such as increased milk and component production and attenuated SARA by improving rumen fermentation, balancing bacterial community and alleviating inflammatory response in the ruminal epithelium. However, there is no conclusive dietary thiamine recommendation for dairy cows, and the impacts of thiamine supplementation on protozoa, solid-attached bacteria, rumen wall-adherent bacteria and nutrient metabolism in dairy cows are still unclear. This knowledge is critical to understand thiamine status and function in dairy cows. Overall, the present review described the current state of knowledge on thiamine nutrition in dairy cows and the major problems that must be addressed in future research.
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.
There have been great efforts on the development of higher-order numerical schemes for compressible Euler equations in recent decades. The traditional test cases proposed thirty years ago mostly target on the strong shock interactions, which may not be adequate enough for evaluating the performance of current higher-order schemes. In order to set up a higher standard for the development of new algorithms, in this paper we present a few benchmark cases with severe and complicated wave structures and interactions, which can be used to clearly distinguish different kinds of higher-order schemes. All tests are selected so that the numerical settings are very simple and any higher order scheme can be straightforwardly applied to these cases. The examples include highly oscillatory solutions and the large density ratio problem in one dimensional case. In two dimensions, the cases include hurricane-like solutions; interactions of planar contact discontinuities with asymptotic large Mach number (the composite of entropy wave and vortex sheets); interaction of planar rarefaction waves with transition from continuous flows to the presence of shocks; and other types of interactions of two-dimensional planar waves. To get good performance on all these cases may push algorithm developer to seek for new methodology in the design of higher-order schemes, and improve the robustness and accuracy of higher-order schemes to a new level of standard. In order to give reference solutions, the fourth-order gas-kinetic scheme (GKS) will be used to all these benchmark cases, even though the GKS solutions may not be very accurate in some cases. The main purpose of this paper is to recommend other CFD researchers to try these cases as well, and promote further development of higher-order schemes.
With the use of temporal derivative of flux function, a two-stage temporal discretization has been recently proposed in the design of fourth-order schemes based on the generalized Riemann problem (GRP) [21] and gas-kinetic scheme (GKS) [28]. In this paper, the fourth-order gas-kinetic scheme will be extended to solve the compressible multicomponent flow equations, where the two-stage temporal discretization and fifth-order WENO reconstruction will be used in the construction of the scheme. Based on the simplified two-species BGK model [41], the coupled Euler equations for individual species will be solved. Each component has its individual gas distribution function and the equilibrium states for each component are coupled by the physical requirements of total momentum and energy conservation in particle collisions. The second-order flux function is used to achieve the fourth-order temporal accuracy, and the robustness is as good as the second-order schemes. At the same time, the source terms, such as the gravitational force and the chemical reaction, will be explicitly included in the two-stage temporal discretization through their temporal derivatives. Many numerical tests from the shock-bubble interaction to ZND detonative waves are presented to validate the current approach.
The metamorphic responses of mussel (Mytilus coruscus) larvae to pharmacological agents affecting G proteins and the adenylate cyclase/cyclic AMP (AC/cAMP) pathway were examined in the laboratory. The G protein activators guanosine 5′-[β,γ-imido]triphosphate trisodium salt hydrate and guanosine 5′-[γ-thio]triphosphate tetralithium salt only induced larval metamorphosis in continuous exposure assays, and the G protein inhibitor guanosine 5′-[β-thio]diphosphate trilithium salt did not exhibit inducing activity. The non-specific phosphodiesterase inhibitor theophylline and the cAMP-specific phosphodiesterase IV inhibitor 4-(3-Butoxy-4-methoxybenzyl)imidazolidin-2-one exhibited inducing activity, while the non-specific phosphodiesterase inhibitor 3-Isobutyl-1-methylxanthine only showed inducing activity at 10−4 M in continuous exposure assays. The cyclic nucleotide analogue N6,2′-O-Dibutyryladenosine 3′,5′-cyclic monophosphate sodium salt did not exhibit significant inducing activity. Both the adenylate cyclase activator forskolin and the adenylate cyclase inhibitor nitroimidazole exhibited inducing activity at 10−4 to 10−3 M concentrations in continuous exposure assays. Among these tested agents, the adenylate cyclase inhibitor (±)-miconazole nitrate salt showed the most promising inducing effect. The present results indicate that G protein-coupled receptors and signal transduction by AC/cAMP pathway could mediate metamorphosis of larvae in this species.
Intra-uterine growth restriction (IUGR) impairs postnatal growth and skeletal muscle development in neonatal infants. This study evaluated whether dietary β-hydroxy-β-methylbutyrate Ca (HMB-Ca) supplementation during the early postnatal period could improve muscle growth in IUGR neonates using piglets as a model. A total of twelve pairs of IUGR and normal-birth-weight (NBW) male piglets with average initial weights (1·85 (sem 0·36) and 2·51 (sem 0·39) kg, respectively) were randomly allotted to groups that received milk-based diets (CON) or milk-based diets supplemented with 800 mg/kg HMB-Ca (HMB) during days 7–28 after birth. Blood and longissimus dorsi (LD) samples were collected and analysed for plasma amino acid content, fibre morphology and the expression of genes related to muscle development. The results indicate that, regardless of diet, IUGR piglets had a significantly decreased average daily weight gain (ADG) compared with that of NBW piglets (P<0·05). However, IUGR piglets fed HMB-Ca had a net weight and ADG similar to that of NBW piglets fed the CON diet. Irrespective of body weight (BW), HMB-Ca supplementation markedly increased the type II fibre cross-sectional area and the mRNA expression of mammalian target of rapamycin (mTOR), insulin-like growth factor-1 and myosin heavy-chain isoform IIb in the LD of piglets (P<0·05). Moreover, there was a significant interaction between the effects of BW and HMB on mTOR expression in the LD (P<0·05). In conclusion, HMB-Ca supplementation during the early postnatal period could improve skeletal muscle growth and maturity by accelerating fast-twitch glycolytic fibre development in piglets.
In this paper, a compact third-order gas-kinetic scheme is proposed for the compressible Euler and Navier-Stokes equations. The main reason for the feasibility to develop such a high-order scheme with compact stencil, which involves only neighboring cells, is due to the use of a high-order gas evolution model. Besides the evaluation of the time-dependent flux function across a cell interface, the high-order gas evolution model also provides an accurate time-dependent solution of the flow variables at a cell interface. Therefore, the current scheme not only updates the cell averaged conservative flow variables inside each control volume, but also tracks the flow variables at the cell interface at the next time level. As a result, with both cell averaged and cell interface values, the high-order reconstruction in the current scheme can be done compactly. Different from using a weak formulation for high-order accuracy in the Discontinuous Galerkin method, the current scheme is based on the strong solution, where the flow evolution starting from a piecewise discontinuous high-order initial data is precisely followed. The cell interface time-dependent flow variables can be used for the initial data reconstruction at the beginning of next time step. Even with compact stencil, the current scheme has third-order accuracy in the smooth flow regions, and has favorable shock capturing property in the discontinuous regions. It can be faithfully used from the incompressible limit to the hypersonic flow computations, and many test cases are used to validate the current scheme. In comparison with many other high-order schemes, the current method avoids the use of Gaussian points for the flux evaluation along the cell interface and the multi-stage Runge-Kutta time stepping technique. Due to its multidimensional property of including both derivatives of flow variables in the normal and tangential directions of a cell interface, the viscous flow solution, especially those with vortex structure, can be accurately captured. With the same stencil of a second order scheme, numerical tests demonstrate that the current scheme is as robust as well-developed second-order shock capturing schemes, but provides more accurate numerical solutions than the second order counterparts.
The formation of deformation and recrystallization textures has been investigated in a Ni7W alloy after heavy cold rolling and subsequent annealing at different temperatures. Cold rolling to a von Mises strain of 4.17 produced a mix of rolling texture that lies between classical brass- and copper-type rolling textures, with the fraction of S({123}<634>), brass({110}<112>), and copper({112}<111>) orientations being 33, 28, and 13%, respectively. The fraction of rolling texture for the deformed Ni7W alloy samples increased slightly during recovery, was then consumed significantly during recrystallization, and dropped to 22% after being annealed at 800 °C for 1 h. The fraction of cube({001}<100>) orientation increased to 26% after primary recrystallization, whereas other random orientations of 43% formed in the Ni7W alloy samples. Further annealing promoted cube grain growth, which lead to a significant strengthening of the cube texture and to a significant loss in high angle boundary (HAB). The fractions of cube texture and HAB of the Ni7W alloy substrate were 92.1 and 27.8%, respectively, after annealing at 1200 °C for 1 h.
Surface properties affect the attachment of micro- and macroscopic marine organisms. The current study examined the settlement response of the mussel Mytilus coruscus plantigrades to natural biofilms formed on surfaces of different wettability. The percentages of plantigrade settlement were not influenced by the biofilms formed on variously wettable surfaces in the short term, but after 10 days, the plantigrade settlement rates decreased on biofilms formed on lower wettability surfaces. In general, lower wettability of the surfaces resulted in the decrease of the dry weight, bacterial and diatom density and the thickness of natural biofilms when compared to high wettability surfaces. In contrast, chlorophyll-a concentration in biofilms was independent of the initial wettability of the surfaces. Comparative cluster analysis of bacterial denaturing gradient gel electrophoresis patterns revealed that high variability existed between the bacterial community on high wettability surfaces and that on low wettability surfaces. Thus, surface wettability affects the formation of natural biofilms, and this variation in biofilms developed on different wettability surfaces may explain the discrepancy in their corresponding inducing activities on M. coruscus plantigrade settlement. This finding provides new insight into interactions between mussel settlement, biofilm characteristics and surface properties.
In this work, mechanical stability, thermodynamic and elastic properties of rhodium (Rh), rhodium monohydride (RhH), and the newly discovered rhodium dihydride (RhH2) under high temperature and pressure are studied by ab initio method together with quasiharmonic Debye model. Mechanical stability test indicates that RhH2 is no longer mechanically stable when pressure is higher than 22.7 GPa, which is quite less than the dynamically stable pressure (90 GPa). The heat capacity at constant volume (Cv) of Rh, RhH, or RhH2 increases proportional to T3 at low temperature, and tends to Dulong–Petit limit (about 241.67, 478.47, and 706.15 J/(kg·K), respectively). The thermal expansion coefficient (α) of Rh, RhH, and RhH2 increases acutely when temperature is not more than 300 K. And then, the increase of α slows down. The α reduces with pressure transiently. H atom's entering in fcc-Rh lattice would greatly change the electron density distribution, which would cause obvious difference in thermodynamic and elastic properties between Rh, RhH, and RhH2.
Background: Several studies have investigated the association of FKBP5 gene polymorphisms with mood disorders, but findings are not always consistent. The aim of our study was to assess the association of FKBP5 gene polymorphisms with mood disorders using a meta-analysis.
Methods: Data were collected from the following electronic databases: PubMed, Elsevier Science Direct, Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure and Wanfang, with the last report up to March 2010. Meta-analysis was performed in a fixed/random effect model.
Results: We identified six studies using search, and one study was excluded because of unavailable data. One study contained data on two different ethnicities and we treated them independently. Thus, six separate studies (2655 cases and 3593 controls) were included in the meta-analysis. Meta-analysis was performed for three FKBP5 gene polymorphisms (rs1360780, rs3800373 and rs4713916) in overall and Caucasian populations. We did not detect any association of FKBP5 gene rs1360780 and rs3800373 polymorphisms with mood disorders (p > 0.05). However, a significant association of FKBP5 gene rs4713916 polymorphism with mood disorders was found, and the heterozygous individual (GA genotype) was more susceptible to mood disorders in comparison to homozygous analogues (GG or AA genotype) [overall: GA vs. GG: OR (odds ratio) = 1.20, 95% CI (confidence interval) = 1.03–1.40, p = 0.02; GA vs. AA: OR = 1.44, 95% CI = 1.09–1.90, p = 0.009; Caucasian: GA vs. GG: OR = 1.22, 95% CI = 1.04–1.44, p = 0.01; GA vs. AA: OR = 1.43, 95% CI = 1.09–1.89, p = 0.01].
Conclusion: This meta-analysis shows that mood disorders are associated with FKBP5 gene rs4713916 polymorphism, but not with rs1360780 and rs3800373.