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The aim of this study was to investigate the combined effect of omega-3 fatty acids (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), at an EPA:DHA ratio of 150:500) and phytosterol esters (PS) on Nonalcoholic fatty liver disease (NAFLD) patients. We conducted a randomized, double-blind, placebo-controlled trial. Ninety-six NAFLD subjects were randomly assigned to the following groups: the PS group (receiving 3.3 g/day phytosterol ester); the FO group (receiving 450mg EPA+1500mg DHA/day); the PS+FO combination group (receiving 3.3 g/day phytosterol ester and 450mg EPA+1500mg DHA/day); and the PO group (a placebo group). The baseline clinical characteristics of the four groups were similar. The primary outcome was liver/spleen attenuation ratio (L/S ratio). The percentage increase in liver/spleen attenuation (≤1) in the PS+FO group was 36% (P=0.083), higher than those in the other three groups (PS group, 11%, P= 0.519; FO group, 18%, P=0.071; PO group, 15%, P=0.436). Compared with baseline, transforming growth factor beta (TGF-β) was significantly decreased in the three study groups at the end of the trial (PS, P=0.000; FO, P=0.002; PS+FO, P=0.001), and tumour necrosis factor alpha (TNF-α) was significantly decreased in the FO group (P=0.036), PS+FO group (P=0.005) and PO group (P=0.032) at the end of the intervention. Notably, TGF-β was reduced significantly more in the PS+FO group than in the PO group (P=0.032). The TG and TC levels of the PS+FO group was reduced by 11.57% and 9.55%, respectively. In conclusion, co-supplementation of PS and EPA+DHA could increase the effectiveness of treatment for hepatic steatosis.
Passive seismology is becoming increasingly popular for glacier/ice-sheet structure investigations in Polar regions. Single-station passive seismic methods including P-wave receiver functions (PRFs), horizontal-to-vertical spectral ratio (HVSR) and a recently proposed autocorrelation method have been used to retrieve glacier/ice-sheet structures. Despite their successful applications, analysis regarding their detection abilities in different glaciological environments has not been reported. In this study, we compare ice thicknesses and vp/vs ratios obtained from the three methods using data collected at GAMSEIS and POLENET/ANET seismic arrays in Antarctica. Ice thickness estimates derived from the three methods are found to be consistent. Comparisons conducted under various model setups, including those involving tiled layers and sedimentary layers, show that the effectiveness of the autocorrelation method is not superior to the PRF method for retrieving ice-sheet structures. The autocorrelation method however can complement other methods as it only requires a single component seismic record.
The cao vit gibbon Nomascus nasutus, also known as eastern black crested gibbon, is categorized as Critically Endangered on the IUCN Red List and was considered one of the world's 25 most threatened primates. The only known population occurs along the border between China and Viet Nam. Accurate information on population size and dynamics is critical for the species’ conservation, but population surveys conducted in only one country may over- or underestimate total population size because the home ranges of cao vit gibbon groups often cross the international border. In 2007 and 2016 we conducted two collaborative transboundary censuses of the cao vit gibbon populations in the Trung Khanh Cao Vit Gibbon Species and Habitat Conservation Area in Viet Nam and the Bangliang Gibbon National Nature Reserve in China. The results showed a population size of 102–110 in 2007, which increased to 107–136 in 2016. Our results indicate that previous surveys conducted separately in Viet Nam and China underestimated the global population size of this species. According to our more comprehensive surveys, the gibbon population is increasing slowly. The gibbons and their habitat are legally protected in both countries. Hunting and charcoal making have not been reported in this area since 2007. As habitat carrying capacity is a limiting factor, habitat restoration is required. However, lack of funding to protect the cao vit gibbon remains a challenge.
Solving the problem of ship weather routing has been always a goal of nautical navigation research and has been investigated by many scientists. The operation schedule of an oceangoing ship can be influenced by wave or wind disturbances, which complicate route planning. In this paper, we present a real-coded genetic algorithm to determine the minimum voyage route time for point-to-point problems in a dynamic environment. A fitness assignment method based on an individual's position in the sorted population is presented, which greatly simplifies the calculation of fitness value. A hybrid mutation operator is proposed to enhance the search for the optimal solution and maintain population diversity. Multi-population techniques and an elite retention strategy are employed to increase population diversity and accelerate convergence rates. The effectiveness of the algorithm is demonstrated by numerical simulation experiments.
A novel hybrid processing has been developed to achieve dense and crack-free mullite films with large critical thicknesses. The amorphous solid nanoparticles obtained from the mullite sol–gel precursor were mixed with the same liquid precursor to form stable suspensions, which were subsequently used to form mullite coatings with the dip-coating method, followed by drying and firing. The hybrid precursor suspensions resulted in highly close-packed nanoparticles, which reduced shrinkage during sintering. Selecting the solvent with a low evaporation rate and high surface tension can effectively eliminate the surface instability caused by the lateral flow during solvent evaporation. The mullite film density was significantly improved at low sintering temperatures, because of the high packing density and viscous flow at above the glass transition temperature of the amorphous gel nanoparticles before crystallization. Dense and crack-free mullite films with 500–600 nm thickness can be obtained from the novel hybrid approach.
Let (M, g(t)) be a compact Riemannian manifold and the metric g(t) evolve by the Ricci flow. In the paper, we prove that the eigenvalues of geometric operator −Δφ +
are non-decreasing under the Ricci flow for manifold M with some curvature conditions, where Δφ is the Witten Laplacian operator, φ ∈ C2(M), and R is the scalar curvature with respect to the metric g(t). We also derive the evolution of eigenvalues under the normalized Ricci flow. As a consequence, we show that compact steady Ricci breather with these curvature conditions must be trivial.
To track the course of development in children's fine-grained perception of Mandarin tones, the present study explored how categorical perception (CP) of Mandarin tones emerges along age among 70 four- to seven-year-old children and 16 adults. Prominent discrimination peaks were found for both the child and the adult groups, and they were well aligned with the corresponding identification crossovers. Moreover, six-year-olds showed a much narrower width (i.e. a sharper slope) compared to younger children, and have already acquired adult-like identification competence of Mandarin high-level and mid-rising tones. Although the ability to discriminate within-category tone pairs did not change, the between-category discrimination accuracies were positively correlated with chronological ages among child participants. We assume that the perceptual refinement of Mandarin tones in young children may be driven by an accumulation of perceptual development from the tonal information of the ambient sound input.
Very high cycle bending fatigue behaviors of FV520B steel under fretting wear were studied by the ultrasonic fatigue technique. The specimen system for ultrasonic bending testing was designed and the stress distribution of fatigue specimen was obtained by finite element method. The microstructure of FV520B steel was characterized by means of optical microscope, transmission electron microscope, and energy-dispersive spectroscope. The P–S–N curve was drawn based on fatigue data. The micromorphology characteristics of fretting wear surface and fracture surface for fatigue specimen were observed. The results indicate that the microstructure of FV520B steel is mainly composed of lath martensite, ferrite, and precipitation particles, with some randomly distributed internal inclusions. The P–S–N curve shows that there exists no “conventional fatigue limit” and the fatigue life decreases continuously with the increase of applied stress Smax. Most of fatigue cracks are observed on fractography and initiate from the overlap region of fretting wear zone and stress concentration zone. The fracture failure for tested specimen is ascribed to fretting wear and bending vibration fatigue.
Postnatal rapid growth by excess intake of nutrients has been associated with an increased susceptibility to diseases in neonates with intra-uterine growth restricted (IUGR). The aim of the present study was to determine whether postnatal nutritional restriction could improve intestinal development and immune function of neonates with IUGR using piglets as model. A total of twelve pairs of normal-birth weight (NBW) and IUGR piglets (7 d old) were randomly assigned to receive adequate nutrient intake or restricted nutrient intake (RNI) by artificially liquid feeding for a period of 21 d. Blood samples and intestinal tissues were collected at necropsy and were analysed for morphology, digestive enzyme activities, immune cells and expression of innate immunity-related genes. The results indicated that both IUGR and postnatal nutritional restriction delayed the growth rate during the sucking period. Irrespective of nutrient intake, piglets with IUGR had a significantly lower villous height and crypt depth in the ileum than the NBW piglets. Moreover, IUGR decreased alkaline phosphatase activity while enhanced lactase activity in the jejunum and mRNA expressions of Toll-like receptor 9 (TLR-9) and DNA methyltransferase 1 (DNMT1) in the ileum of piglets. Irrespective of body weight, RNI significantly decreased the number and/or percentage of peripheral leucocytes, lymphocytes and monocytes of piglets, whereas the percentage of neutrophils and the ratio of CD4+ to CD8+ were increased. Furthermore, RNI markedly enhanced the mRNA expression of TLR-9 and DNMT1, but decreased the expression of NOD2 and TRAF-6 in the ileum of piglets. In summary, postnatal nutritional restriction led to abnormal cellular and innate immune response, as well as delayed the growth and intestinal development of IUGR piglets.
Considerable controversy exists regarding the associations of dietary patterns with the risk of all-cause, CVD and stroke mortality. Therefore, a meta-analysis was conducted to elucidate the potential associations between dietary patterns and the risk of all-cause, CVD and stroke mortality. The PubMed database was searched for prospective cohort studies on the associations between dietary patterns and the risk of all-cause, CVD and stroke mortality published until February 2014. Random-effects models were used to calculate the summary relative risk estimates (SRRE) based on the highest v. the lowest category of dietary pattern scores. Stratified analyses were conducted based on sex, geographical region, follow-up duration, and adjustment/non-adjustment for energy intake. A total of thirteen prospective cohort studies involving 338 787 participants were included in the meta-analysis. There was evidence of inverse associations between the prudent/healthy dietary pattern and the risk of all-cause (SRRE = 0·76, 95 % CI 0·68, 0·86) and CVD (SRRE = 0·81, 95 % CI 0·75, 0·87) mortality and an absence of association between this dietary pattern and stroke mortality (SRRE = 0·89, 95 % CI 0·77, 1·02). However, no significant associations were observed between the Western/unhealthy dietary pattern and the risk of all-cause (SRRE = 1·07, 95 % CI 0·96, 1·20), CVD (SRRE = 0·99, 95 % CI 0·91, 1·08) and stroke (SRRE = 0·94, 95 % CI 0·81, 1·10) mortality. In conclusion, the findings provide evidence that greater adherence to a prudent/healthy dietary pattern is associated with a lower risk of all-cause and CVD mortality and not significantly associated with stroke mortality and that the Western/unhealthy dietary pattern is not associated with all-cause, CVD and stroke mortality. Further studies are required to confirm these findings.
The unsteady flow separation of airfoil with a local flexible structure (LFS) is studied numerically in Lagrangian frames in detail, in order to investigate the nature of its high aerodynamic performance. For such aeroelastic system, the characteristic-based split (CBS) scheme combined with arbitrary Lagrangian-Eulerian (ALE) framework is developed firstly for the numerical analysis of unsteady flow, and Galerkin method is used to approach the flexible structure. The local flexible skin of airfoil, which can lead to self-induced oscillations, is considered as unsteady perturbation to the flow. Then, the ensuing high aerodynamic performances and complex unsteady flow separation at low Reynolds number are studied by Lagrangian coherent structures (LCSs). The results show that the LFS has a significant influence on the unsteady flow separation, which is the key point for the lift enhancement. Specifically, the oscillations of the LFS can induce the generations of moving separation and vortex, which can enhance the kinetic energy transport from main flow to the boundary layer. The results could give a deep understand of the dynamics in unsteady flow separation and flow control for the flow over airfoil.
First principle calculations are employed scheme to investigate the electronic structures and mechanical properties of AlCu3 with divacancy defects using the pseudopotential plane wave method. The defect crystal is constructed by removing the nearest Al or Cu atoms to form the double point vacancies. Calculated lattice constants agree well with the experimental data. Moreover, structural stabilities of crystals containing divacancy are reduced. Results reveal that the crystal with double Cu vacancy defects is more stable than that of Al. Calculations of defect formation energies indicate that the divacancy of Cu is easier to exist in AlCu3. Divacancy defects play an important role to improve the mechanical properties of AlCu3 and corresponding ductility, stiffness and plasticity are increased. Furthermore, chemical bonds become weaker since the divacancy are introduced. Hybridizations between orbits of crystals are analyzed to account for the interactions in perfect and defect structures. Accordingly, implications of these findings on the mechanism of divacancy are discussed.
The present study was conducted to investigate the effects of chitosan (CS)-Zn on intestinal morphology, mucosal epithelial cell apoptosis and mucosal immune function in weanling pigs. A total of 150 weanling barrows with a body weight of 7·2 kg were randomly allocated into five groups. A basal diet without Zn supplementation was used as the control and other four groups were fed the control diet supplemented with 50 or 100 mg/kg of Zn as CS-Zn, 100 mg/kg of Zn as ZnSO4 and 3000 mg/kg of Zn as ZnO, respectively. The feeding trial lasted for 28 d. The results showed that serum diamine oxidase activities, d-lactate levels and endotoxin contents were lower in pigs fed dietary 100 mg/kg of Zn as CS-Zn or 3000 mg/kg of Zn as ZnO than in pigs fed the control or 100 mg Zn/kg as ZnSO4 diet. The ratios of the villus height:crypt depth of the duodenum, jejunum and ileum were higher in pigs that received 100 mg/kg of Zn as CS-Zn or a high level of Zn as ZnO than in pigs fed the control diet. Moreover, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL)-stained ileal epithelial cells were found in the control group, and apoptotic cells did not appear prominently in pigs that received the 100 mg/kg of CS-Zn or ZnO diet. Secretory IgA concentration in ileal mucus was increased in the dietary group that received 100 mg/kg of CS-Zn or ZnO. These results indicated that dietary 100 mg CS-Zn/kg had similar biological effects to dietary 3000 mg ZnO/kg on intestinal morphology, mucosal epithelial cell apoptosis and mucosal immune function.
A review of recently published temporal data from Shuidonggou Locality 1 indicates that a 40–43 cal ka date for the inception of Initial Upper Paleolithic (IUP) blade-oriented technologies in East Asia is warranted. Comparison of the dates from Shuidonggou to other Asian IUP dates in Korea, Siberia, and Mongolia supports this assertion, indicating that the initial appearance of the IUP in East Asia generally corresponds in time to the fluorescence of the IUP in eastern Europe and western Asia. This conclusion preliminarily suggests that either a version of the IUP originated independently in East Asia just prior to 40 cal ka, or more likely, that an early, initial diffusion of the IUP into East Asia occurred ∼41 cal ka, a hypothesis consistent with current estimates for the evolution or arrival of modern humans in the region.
We conducted an interview survey around and within Mengla and Shangyong Nature Reserves, Mengla County, Yunnan, China, in December 2008 to ascertain whether gibbons were present in the area, and in December 2011 we surveyed two sites in the Reserves for the northern white-cheeked gibbon Nomascus leucogenys. We found no signs of the existence of gibbons during the survey. Illegal hunting was common at both sites. Only 36 individuals in nine groups were recorded in Mengla and Shangyong Nature Reserves in the 1980s, and this small and fragmented population was probably unable to survive the pressure of hunting. No white-cheeked gibbon was recorded in Huanglianshan Nature Reserve in a survey carried out by other researchers in 2003. Gibbons have a very low chance of survival in unprotected forest, and we conclude that the white-cheeked gibbon is extinct, or at least ecologically extinct, in China.
To clarify the effects of a Cryptocaryon irritans infection on the physiological functions of the marbled rockfish Sebastiscus marmoratus, this study utilized C. irritans at concentrations of 2500; 5000; 7500; 10 000; 20 000; and 30 000 theronts/fish to infect marbled rockfish weighing 45±3 g. The survival rate, food intake, respiratory rate, serum ion concentrations and gill Na+/K+-ATPase activity were determined. With the increase of the infection concentration and the passage of time, the survival rate of the rockfish gradually decreased. The groups infected with more than 5000 theronts/fish had stopped feeding within 4 days. The respiratory rates of the fish in the groups infected with 2500 and 5000 theronts/fish initially increased and then decreased. In contrast, the respiratory rate of the fish in the groups infected with more than 7500 theronts/fish was elevated to levels significantly higher than the control group after 12 h. The Na+/K+-ATPase activity and serum Na+ and Cl− concentrations increased with increasing infection concentration. In conclusion, the physiological functions of the fish infected with low concentrations of C. irritans can be effectively restored, whereas a high concentration infection induced severe stress. The declined food intake and accelerated respiratory rate could be useful for an early warning system as important indicators.
Based on 187 galaxy clusters identified from the photometric redshifts of galaxies in the Cosmic Evolution Survey (COSMOS) field(Wen & Han 2011), cluster galaxies brighter than MV = -20.5 are classified into four categories according to their best-fitting templates of the spectral energy distributions (SEDs) provided by Ilbert et al. (2009): early-type (including elliptical and lenticular) galaxies (E+S0), spiral galaxies (S), irregular galaxies (Irr), and starbursts (SB). The fractions of these four SED types are presented as the functions of redshift in Figure 1. Fraction of each category varies remarkably with cluster redshift: fractions of normal galaxies (E+S0+S+Irr) tend to decrease with redshift, whilst the starburst proportion tends to increase with redshift. For the normal galaxies, there exists a sequence for the decreasing slopes of morphological fractions. Majority of the galaxies in high-redshift clusters (z > 1.0) are experiencing strong star-formation activities, which leads to a very high proportion of starburst.
Chen et al. (2011) found that the durations (timescales) of the normal and abnormal modes of PSR B0329+54 follow a gamma distribution, and constrained the parameters of the distribution function. In this paper, we perform a further analysis on the relationship between the timescales of the two modes. The ratio between the durations of a normal mode and the succeeding abnormal mode is calculated for 54 such pairs. It is found that the cumulative distribution function (CDF) of the ratio is consistent with the CDF obtained by assuming random mode switching, suggesting that the two modes work independently.
Theoretically dense ZrB2–SiC two-phase microstructures were isothermally oxidized for ∼90 min in flowing air in the range 1500–1900 °C. Specimens with 30 mol% SiC formed distinctive reaction product layers that were highly protective; 28 mol% SiC–6 mol% TaB2 performed similarly. At and above 1700 °C, the composition with only 15 mol% SiC oxidized extensively because of deficient silicate liquid formation. Specimens with 60 mol% SiC were resistant to oxidation up to 1800 °C; at 1900 °C, this composition displayed periodic ruptures of the passivating layer by emerging gas bubbles. Oxide coating thicknesses calculated from weight loss data were consistent with those measured from scanning electron microscopy micrographs. A layer of ZrB2 devoid of SiC was argued to be from preferential removal of SiC by reaction of a silica oxidation product with adjacent unreacted SiC to form escaping gases.
We conducted an intensive survey of the Vulnerable eastern hoolock gibbon Hoolock leuconedys along the west bank of the Salween River in southern China, covering all known hoolock gibbon populations in China. We found 40–43 groups, with a mean group size of 3.9, and five solitary individuals. We estimated the total population to be < 200. In the nine groups for which we recorded composition, seven comprised one adult pair and 0–3 offspring and the other two groups both comprised one adult male and two adult females. The population is severely fragmented, in 17 locations, with the largest subpopulation containing only five family groups. Compared with the population in 1985 and 1994 five subpopulations have declined and gibbons have been extirpated from nine localities, although we discovered two previously unknown subpopulations. Commercial logging, illegal hunting, agricultural encroachment and population fragmentation pose serious threats to the future of H. leuconedys in China. An integrated conservation plan, including nature reserve establishment/expansion, enforcement of existing laws, conservation education, translocation and conservation-oriented research are needed to ensure the survival of H. leuconedys in China.