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This paper aims to build the finite element model of the composite sinusoidal specimens and to carry out the parametric analysis. In this paper, the damage behaviour and the energy-absorbing results of composite sinusoidal specimens have been studied by quasi-static crushing experiments. The failure mechanisms of specimens under quasi-static crushing is further analysed. A numerical simulation has been performed by using the finite element model code LS-DYNA. The numerical results, in terms of load -displacement data, have been compared against experimental data, and good agreement has been found. Moreover, a sensitivity study has been carried out by varying material properties in order to assess their influence on the numerical results, and the material parameter selection scheme is optimised based on the constructed corresponding response surfaces. The results show that the response surface model has passed the test of goodness of fit, and the optimisation method can effectively assist the finite element modelling, and greatly decrease the numbers of trial and error.
In the current intensive production system, ruminants are often fed high-grain (HG) diets. However, this feeding pattern often causes rumen metabolic disorders and may further trigger laminitis, the exact mechanism is not clear. This study investigated the effect of HG diet feeding on fermentative and microbial changes in the rumen and on the expression of pro-inflammatory cytokines and matrix metalloproteinases (MMPs) in the lamellar tissue. In all, 12 male goats were fed a hay diet (0% grain; n=6) or an HG diet (56.5% grain; n=6). On day 50 of treatment, samples of blood, rumen content, and lamellar tissue of hooves of goats were collected. The data showed that compared with the hay group, HG-fed goats had lower (P<0.05) rumen pH but higher (P<0.05) total volatile fatty acids and lactate in the rumen and higher (P<0.05) lipopolysaccharide (LPS) levels in the rumen and blood. HG diet feeding altered the composition of rumen bacterial community, and correspondingly, the results suggested that their functions in the HG group were also altered. HG diet feeding increased (P<0.05) the expression of interleukin-1β, interleukin-6, tumour necrosis factor-α and MMP-2 mRNA in the lamellar tissues compared with the hay group. Correlation analysis indicated that the expression of pro-inflammatory cytokines were positively correlated with MMP-2 expression in lamellar tissues. Overall, these results revealed that HG feeding altered the patterns of rumen fermentation and the composition and functions of rumen bacterial community, and lead to higher levels of LPS in the peripheral blood, and further activated the inflammatory response in lamellar tissues, which may progress to the level of laminar damage.
To explore the effects of maternal nutrition on offspring muscle characteristics, a total of 56 sows were assigned to one of the four dietary groups during gestation: control (CON), or control diets supplemented with methyl donor (MET), bisphenol A (BPA), and combined BPA and MET (BPA+MET). Compared with CON offspring, MET offspring showed a higher meat redness value, but lower glycogen content in the longissimus thoracis (LT). Moreover, compared with CON offspring, MET offspring showed lower LT glycogen synthase (GS) mRNA levels at birth and the finishing stage, and increased methylation at the GS promoter. Prenatal BPA exposure reduced the pH and redness value of meat, but increased the lightness value, lactate content, glycolytic potential and lactate dehydrogenase (LDH) enzyme activity in the LT muscle. Prenatal BPA exposure increased LDH mRNA levels in the LT muscle at birth and the finishing stage, and reduced methylation at the LDH promoter. Thus, maternal MET affects muscle GS and LDH expression via DNA methylation, thereby resulting in persistent effects on pork quality.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5×106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or high-explosive detonation. This morphology has not been reported previously in cosmic material, but has been observed in terrestrial impact material. This is the first highly enriched, discrete layer of NDs observed in glacial ice anywhere, and its presence indicates that ice caps are important archives of ET events of varying magnitudes. Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at numerous North American sites in a sedimentary layer, the Younger Dryas boundary layer (YDB), dating to 12.9 ± 0.1 ka. However, more investigation is needed to confirm this association.
The use of limiters may impact both accuracy and resolution of a solution. And the accuracy and resolution are highly dependent on the amount of numerical dissipation in a scheme, so the ability of limiters to control numerical dissipation should be improved. In this view, based on the examination of several classical limiters to control dissipation, a class of general piecewise-linear flux limiters (termed GPL limiters) are presented in this paper for Multi-step time-space-separated unsteady schemes. The GPL limiters can satisfy the second-order TVD criterion and contain some existing limiters such as Superbee and Minmod. Using the decrement of discrete total entropy to represent the amount of numerical dissipation, an entropy dissipation function of GPL limiters is defined with three parameter variables. By proving the monotonicity of this function, a new GPL type limiter (named MDF individually), which can minimize the numerical dissipation and improve the calculation accuracy, is proposed. A high resolution entropy-consistent scheme is obtained by MDF limiter, which will be proved to satisfy entropy stability and entropy consistency. Computational results of this scheme for several 1-D and 2-D Euler test cases are presented, demonstrating the accuracy, monotonicity and robustness of MDF limiter.
Mycobacterial diseases are prevalent in cancer and rheumatoid arthritis (RA) patients, especially those receiving tumor necrosis factor-α inhibitor (TNFi). However, the impact of cancer development on the risk of mycobacterial diseases among RA patients is unknown. Data from the Taiwan National Health Insurance Research Database were used to conduct a retrospective study to assess the occurrence of mycobacterial diseases in RA patients developing cancer (cancer-positive), those using TNFi (TNFi-exposure), those with cancer and using TNFi (cancer-TNFi-comb), and those without cancer and not using TNFi (cancer-TNFi-free). Cancer and TNFi exposure were time-dependent, and independent risk factors of mycobacterial diseases were assessed by Cox regression. Among 1344 RA patients diagnosed during 2000–2013, 68 (5·1%) developed cancer before their end points. The incidence rates of mycobacterial diseases in the cancer-positive (n = 56), TNFi-exposure (n = 290), cancer-TNFi-comb (n = 12), and cancer-TNFi-free (n = 986) subgroups were 6·7, 2·0, 7·6, and 1·3 per 1000 person-years, respectively. As compared with the cancer-TNFi-free group, the risk for mycobacterial diseases increased for the TNFi-exposure group (adjusted HR = 3·6, 95% confidence interval (95% CI) 1·1–11·5, P = 0·032) and remained high for cancer-positive (adjusted HR = 14·6, 95% CI 3·3–63·7, P < 0·001) after adjustment. This study suggested that cancer development increased the risk of mycobacterial diseases in RA patients, and risk assessment for this subgroup should be considered.
Elderly individuals with tuberculosis (TB) are more likely to have a non-specific clinical presentation of TB and high mortality. However, factors associated with mortality in elderly TB patients have not been extensively studied. This retrospective cohort study aimed to identify factors associated with death among elderly Taiwanese with TB. All elderly patients with TB from 2006 to 2014 in Taipei, Taiwan, were included in a study. Multiple logistic regression was used to identify the factors associated with death in elderly TB patients. The mean age of the 5011 patients was 79·7 years; 74·1% were men; 32·7% had mortality during the study follow-up period. After controlling for potential confounders, age ⩾75 years (reference: 65–74 years), male sex, end-stage renal disease (ESRD), malignancy, acid-fast bacilli-smear positivity, TB-culture positivity, pleural effusion on chest radiograph and notification by an ordinary ward or intensive care unit were associated with a higher risk of all-cause death; while high school, and university or higher education, cavity on chest radiograph and directly observed therapy were associated with a lower risk of all-cause death. This study found that the proportion of death among elderly patients with TB in Taipei, Taiwan, was high. To improve TB treatment outcomes, future control programmes should particularly target individuals with comorbidities (e.g. ESRD and malignancy) and those with a lower socio-economic status (e.g. not educated).
In individuals with latent tuberculosis (TB) infection, those living with human immunodeficiency virus (HIV) had a 20–37 times higher risk of developing active TB compared to those without HIV infection. Systematic testing and treatment of latent TB infection are priorities in HIV-infected persons. In China, the prevalence of HIV infection in men who have sex with men (MSM) has gradually increased in the past decade. However, the prevalence of TB infection has been studied sparsely in HIV-infected MSM. Hence, we conducted a pilot study in MSM living with HIV infection in Xi'an city to evaluate TB infection status by means of interferon-γ release assay (IGRA). A total of 182 HIV-infected MSM were included in this study, the prevalence of IGRA positivity was observed to be 8·79% (16/182). IGRA quantitative results were not statistically influenced by the CD4 cell counts of the study participants. However, IGRA positivity was found to be lower than our previously reported data from the general population. This suggests that immunological deficiency might decrease the sensitivity of IGRA and thus increase the number of false negatives. Our primary results, suggesting systematic testing and treatment of latent TB infection together with active case-finding, were equally important for TB control in persons living with HIV infection.
Accelerator mass spectrometry (AMS) radiocarbon dating a continuous core from Lake Gun Nur, northern Mongolia, shows a period between 10 and 8 ka BP that could not be dated accurately. Further dating on alkali-insoluble residue and humic acid from the same samples in the Gun Nur core suggest that this AMS 14C date anomaly is neither analytical nor material related. We hypothesize that the 14C anomaly may be derived from increasing production rates of 14C caused by diminished solar activity, a low 14CO2/14CO ratio in the atmosphere, or an unstable 14C flux in the lower atmosphere caused by changing geomagnetic field strength. Our results imply that the 14C data used for 14C age calibration cannot correct the age-depth regression between 8 and 10 ka BP to fit the age-depth model along with other time intervals.
There are six strains of the complete genomic sequences of black queen cell virus (BQCV) published in the GenBank, including South Africa (AF183905), South Korea (JX149531), Hungary 10 (EF517515), Poland 4 (EF517519), Poland 5 (EF517520) and Poland 6 (EF517521). Based on the six BQCV strains published in the GenBank, ten pairs of primers were designed in the present study using reverse transcription polymerase chain reaction to obtain the first complete genome sequence of a BQCV strain in China, called the BQCV China-JL1 strain (KP119603). A phylogenetic tree was then built to analyse their genetic relationships. The BQCV China-JL1 strain showed 86–93% similarity with the six strains published in the GenBank. The BQCV China-JL1 strain consisted of 8358 nucleotides (nt). The 5′-proximal open reading frame (ORF1) initiated at nt position 546 and terminated at nt position 4676, ORF3 initiated at nt position 4891 and terminated at nt position 5433, and the 3′-proximal ORF (ORF2) was located between nt positions 5750 and 8203.
The genetic influences in human brain structure and function and impaired functional connectivities are the hallmarks of the schizophrenic brain. To explore how common genetic variants affect the connectivities in schizophrenia, we applied genome-wide association studies assaying the abnormal neural connectivities in schizophrenia as quantitative traits.
We recruited 161 first-onset and treatment-naive patients with schizophrenia and 150 healthy controls. All the participants underwent scanning with a 3 T-magnetic resonance imaging scanner to acquire structural and functional imaging data and genotyping using the HumanOmniZhongHua-8 BeadChip. The brain-wide association study approach was employed to account for the inherent modular nature of brain connectivities.
We found differences in four abnormal functional connectivities [left rectus to left thalamus (REC.L–THA.L), left rectus to right thalamus (REC.L–THA.R), left superior orbital cortex to left thalamus (ORBsup.L–THA.L) and left superior orbital cortex to right thalamus (ORBsup.L–THA.R)] between the two groups. Univariate single nucleotide polymorphism (SNP)-based association revealed that the SNP rs6800381, located nearest to the CHRM3 (cholinergic receptor, muscarinic 3) gene, reached genomic significance (p = 1.768 × 10−8) using REC.L–THA.R as the phenotype. Multivariate gene-based association revealed that the FAM12A (family with sequence similarity 12, member A) gene nearly reached genomic significance (nominal p = 2.22 × 10–6, corrected p = 0.05).
Overall, we identified the first evidence that the CHRM3 gene plays a role in abnormal thalamo-orbital frontal cortex functional connectivity in first-episode treatment-naive patients with schizophrenia. Identification of these genetic variants using neuroimaging genetics provides insights into the causes of variability in human brain development, and may help us determine the mechanisms of dysfunction in schizophrenia.
We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of age was 397,466. As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood. After adjusting the results for birth weight, the birth order differences decreased and were no longer statistically significant. First-born twins had greater BMI than the second-born twins over childhood and adolescence. After adjusting the results for birth weight, birth order was still associated with BMI until 12 years of age. No interaction effect between birth order and zygosity was found. Only limited evidence was found that birth order influenced variances of height or BMI. The results were similar among boys and girls and also in MZ and DZ twins. Overall, the differences in height and BMI between first- and second-born twins were modest even in early childhood, while adjustment for birth weight reduced the birth order differences but did not remove them for BMI.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
We determined the prevalence and seasonality of infections by Fasciola of goats and bovine species (cattle and water buffalo) in Hubei and Anhui provinces of China. Faecal samples were collected at 2- to 3-month intervals from 200 goats in Hubei province and from 152 bovine species in Anhui province. All faecal samples were examined for the presence of parasites. We determined the nucleotide sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA (rDNA) of 39 Fasciola worms from Anhui province. The prevalence of Fasciola infection in goats ranged between 3.5 and 37.0%, with mean eggs per gram (EPG) ranging between 29.0 and 166.0. Prevalence and EPG exhibited downward trends over time with significant differences. The prevalence of Fasciola infection in cattle ranged between 13.3 and 46.2% (mean EPG, 36.4–100.0), and that of water buffalo ranged between 10.3 and 35.4% (mean EPG, 25.0–89.6), with a higher prevalence of infection and EPG from June to October compared with December to March. Analysis of ITS-1 and ITS-2 sequences revealed that F. hepatica and F. gigantica were present in all bovine species of Anhui province and that F. gigantica mainly infected water buffalo. This is the first demonstration of Fasciola infection in Hubei province and detection of F. hepatica and F. gigantica in Anhui province. The present study of Hubei province shows that mass treatment of livestock with closantel sodium injections in April and August/September controlled Fasciola infection effectively.
The need for higher energy density batteries has spawned recent renewed interest in alternatives to lithium ion batteries, including multivalent chemistries that theoretically can provide twice the volumetric capacity if two electrons can be transferred per intercalating ion. Initial investigations of these chemistries have been limited to date by the lack of understanding of the compatibility between intercalation electrode materials, electrolytes, and current collectors. This work describes the utilization of hybrid cells to evaluate multivalent cathodes, consisting of high surface area carbon anodes and multivalent nonaqueous electrolytes that are compatible with oxide intercalation electrodes. In particular, electrolyte and current collector compatibility was investigated, and it was found that the carbon and active material play an important role in determining the compatibility of PF6-based multivalent electrolytes with carbon-based current collectors. Through the exploration of electrolytes that are compatible with the cathode, new cell chemistries and configurations can be developed, including a magnesium-ion battery with two intercalation host electrodes, which may expand the known Mg-based systems beyond the present state of the art sulfide-based cathodes with organohalide-magnesium based electrolytes.
A combined experimental and computational study on a rectangular lobed mixer is performed. A series of simulations based on a steady Reynolds-averaged Navier-Stokes Simulation (RANS) are conducted to analyse the mixing mechanisms of large-scale streamwise structure shed by the trailing edge of lobed mixer, with emphasis being placed on the effect of turbulence modeling and inflow conditions. The simulations are validated in respect of velocity and scalar distribution against the data obtained through Particle Image Velocimetry (PIV) and Nanoparticle-based Planar Laser Scattering (NPLS) technique. The computational results predicted by the SST k –ω turbulence model show better agreement with the experimental data. But the small-scale turbulence structures are not captured accurately by these turbulence models. The convoluted shear layer shed from trailing edge is stretched and rotated by the large-scale streamwise vortices, forming an unstable ‘pinching-off’ structure, which increases the interfacial area. And at the interface of two streams, a large number of small-scale turbulence structures are formed, which contribute a lot to the mixing enhancement along with the increased interfacial area. The streamwise vorticity decays more rapidly with the decrease of velocity ratio and total pressure ratio of two streams. The scalar thickness which reflects the mixing rate of two streams increases with the decreasing velocity ratio and total pressure ratio.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Rice (Oryza sativa L.) is one of the most important cereal crops in the world and a potentially important source of zinc (Zn) in the diet. The improvement of Zn content of rice is a global challenge with implications for both rice production and human health. The objective of the present study was to identify the effects of nitrogen (N) fertilizer rates and Zn application methods on Zn content of rice by evaluating rice production on native soils with different Zn availabilities in 2010/11. The results indicated that Zn application increased rice grain yield and Zn content in grains compared with the control; however, this effect was also affected by the native soil Zn availability, N fertilizer rate and Zn fertilizer application method. The native soil Zn status was the dominant factor influencing grain yield and grain Zn content in response to Zn fertilizer application. Grain Zn content ranged from 19·74 to 26·93 mg/kg under the different Zn statuses. The results also indicated that Zn application method has a significant influence on grain yield. Application of Zn fertilizer to the soil was more effective than the foliar spray on rice grain yield; however, the foliar spray resulted in a greater increase in grain Zn content when compared with soil application. Grain Zn content was affected by application method and displayed the following general trend: soil application + foliar spray > foliar spray > soil application. The experiments investigating the effect of N fertilizer rate combined with Zn application method showed a clear increase in both grain yield and Zn content as the N fertilizer level increased from 200 to 300 kg/ha. In addition, the results also indicated that N content and accumulation increased in all plant tissues, which suggests that Zn application might influence the uptake and translocation of N in rice plants. These results suggest that soil application in addition to a foliar spray of Zn should be considered as an important strategy to increase grain yield and grain Zn content of rice grown in soils with low background levels of Zn-associated diethylene triamine pentaacetate acid. Moreover, this process could be further strengthened by a high N application rate. In conclusion, these results demonstrate the potential of optimizing nutrient management using Zn fertilizer to obtain higher grain yields and higher grain Zn content in fields with low native Zn status.
Background: Assessment of ischemic penumbra during the acute stage of cerebral infarction is crucial for a decision to initiate thrombolytic therapy and for predicting stroke evolution. Although controversial as a perfect equivalence to penumbra, perfusion weighted imaging (PWI)-diffusion weighted imaging (DWI) mismatch may predict the response to thrombolysis. Due to the reliance on contrast agents in PWI, noninvasive alternatives remain an unmet need. Methods: We herein investigate the potentials of SWI as an alternative to PWI in defining ischemic penumbra and in predicting stroke outcome. A multimodal magnetic resonance imaging work-up which includes conventional magnetic resonance imaging sequences (T1WI, T2WI and FLAIR), DWI, PWI and SWI was performed. The Alberta Stroke Programme Early CT Score (ASPECTS) was used to evaluate the changes in DWI, SWI and PWI. Results: The mismatch of SWI-DWI was comparable with that of PWI-DWI (p>0.05). Furthermore, the grade of prominent vein and the cerebral blood volume in the ipsilateral brain tissue were positively correlated. Conclusions: SWI can be used as a noninvasive alternative to identify occlusive arteries and to evaluate the ischemic penumbra. The susceptibility vein sign may represent thrombosis in arteries whereby being helpful to identify responsible blood vessels in ischemic stroke.