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The present study aimed to evaluate the validity and reproducibility of a thirteen-item FFQ regarding identification of dietary conditions in a rural population in China.
A reproducibility study repeated the first FFQ (FFQ1) approximately 4 weeks later (FFQ2). A validity study evaluated the mean of three consecutive 24 h diet recalls as the reference measure.
Residents of a rural area in Henan Province, which is located in the central region of China.
A total of 295 individuals participated in the reproducibility study. In addition, 123 people agreed to participate in the validity study. Spearman’s correlation coefficients between the two FFQ ranged from 0·06 (vegetables) to 0·58 (eggs). Spearman’s correlation coefficients between the two methods of collection ranged from 0·01 for cereal to 0·49 for staple foods. The mean of the intraclass correlation coefficients of the two FFQ (FFQ1 v. FFQ2) was 0·19. Bland–Altman analysis indicated good agreement for most food groups across the range of intake for the two studies.
The study demonstrated that our FFQ design could be used as a representative tool to conduct a dietary evaluation of a rural population.
Subacute ruminal acidosis (SARA) can increase the level of inflammation and induce rumenitis in dairy cows. Berberine (BBR) is the major active component of Rhizoma Coptidis, which is a type of Chinese anti-inflammatory drug for gastrointestinal diseases. The purpose of this study was to investigate the anti-inflammatory effects of BBR on lipopolysaccharide (LPS)-stimulated rumen epithelial cells (REC) and the underlying molecular mechanisms. REC were cultured and stimulated with LPS in the presence or absence of different concentrations of BBR. The results showed that cell viability was not affected by BBR. Moreover, BBR markedly decreased the concentrations and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6 in the LPS-treated REC in a dose-dependent manner. Importantly, Western blotting analysis showed that BBR significantly suppressed the protein expression of toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein (MyD88) and the phosphorylation of nuclear factor-κB (NF-κB), inhibitory kappa B (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in LPS-treated REC. Furthermore, the results of immunocytofluorescence showed that BBR significantly inhibited the nuclear translocation of NF-κB p65 induced by LPS treatment. In conclusion, the protective effects of BBR on LPS-induced inflammatory responses in REC may be due to its ability to suppress the TLR4-mediated NF-κB and MAPK signaling pathways. These findings suggest that BBR can be used as an anti-inflammatory drug to treat inflammation induced by SARA.
The turbulence state in a supersonic boundary layer subjected to a transverse sonic jet is studied by conducting direct numerical simulations. Turbulence statistics for two jet-to-cross-flow momentum flux ratios
of 2.3 and 5.5 based on the previous simulation (Sun & Hu, J. Fluid Mech., vol. 850, 2018, pp. 551–583) are given and compared with a flat-plate boundary layer without a jet
. The instantaneous and time-averaged flow features around the transverse jet in the supersonic boundary layer are analysed. It is found that, in the near-wall region, turbulence is suppressed significantly with increasing
in the lateral boundary layer around the jet and the turbulence decay is retained in the downstream recovery region. The local boundary-layer thickness decreases noticeably in the lateral downstream of the jet. Analysis of the cross-flow streamlines reveals a double-expansion character in the vicinity of the jet, which involves the reattachment expansion related to the flow over the jet windward separation bubble and the jet lateral expansion related to the flow around the jet barrel shock. The double expansion leads to the turbulence decay in the jet lateral boundary layer and causes a slow recovery of the outer layer in the far-field boundary layer. A preliminary experiment based on the nanoparticle laser scattering technique is conducted and confirms the existence of the turbulence decay phenomenon.
In a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) rotation system, a study was conducted to determine the effects of different fertilization regimens (no fertilization, replacement of a portion of chemical fertilizer with composted pig manure, chemical fertilizer only, and straw return combined with chemical fertilizer) on the weed communities and wheat yields after 4 and 5 yr. The impact of the long-term recurrent fertilization regimen initiated in 2010 on the composition and diversity of weed communities and the impact of the components and total amount of fertilizer on wheat yields were assessed in 2014 and 2015. Totals of 19 and 16 weed species were identified in experimental wheat fields in 2014 and 2015, respectively, but the occurrence of weed species varied according to the fertilization regimen. American sloughgrass [Beckmannia syzigachne (Steud.) Fernald], water starwort [Myosoton aquaticum (L.) Moench], and lyrate hemistepta (Hemistepta lyrata Bunge.) were adapted to all fertilization treatments and were the dominant weed species in the experimental wheat fields. The greatest number of weed species were observed under the no-fertilization treatment, in which 40% of the weed community was composed of broadleaf weeds and the lowest wheat yields were obtained. With fertilizer application, the number of weed species was reduced, the height of weeds increased significantly, the density of broadleaf weeds was significantly reduced, the biodiversity indices of weed communities decreased significantly, and higher wheat yields were obtained. Only the chemical fertilizer plus composted pig manure treatment and the chemical fertilizer–only treatment increased the density of grassy weeds and the total weed community density. The treatment with chemical fertilizer only also resulted in the highest density of B. syzigachne. Rice straw return combined with chemical fertilizer yielded the lowest total weed density, which suggests that it inhibited occurrence of weeds. The different fertilizer regimens not only affected the weed species composition, distribution, and diversity, but also the weed density. Our study provides new information from a rice–wheat rotation system on the relationship between soil amendments and agricultural weed infestation.
Limited information is available on the prevalence and effect of hypertriglyceridaemic–waist (HTGW) phenotype on the risk of type 2 diabetes mellitus (T2DM) in rural populations.
In the present cross-sectional study, we investigated the prevalence of the HTGW phenotype and T2DM and the strength of their association among rural adults in China.
HTGW was defined as TAG >1·7 mmol/l and waist circumference (WC) ≥90 cm for males and ≥80 cm for females. Logistic regression analysis yielded adjusted odds ratios (aOR) relating risk of T2DM with HTGW.
Adults (n 12 345) aged 22·83–92·58 years were recruited from July to August of 2013 and July to August of 2014 from a rural area of Henan Province in China.
The prevalence of HTGW and T2DM was 23·71 % (males: 15·35 %; females: 28·88 %) and 11·79 % (males: 11·15 %; females: 12·18 %), respectively. After adjustment for sex, age, smoking, alcohol drinking, blood pressure, physical activity and diabetic family history, the risk of T2DM (aOR; 95 % CI) was increased with HTGW (v. normal TAG and WC: 3·23; CI 2·53, 4·13; males: 3·37; 2·30, 4·92; females: 3·41; 2·39, 4·85). The risk of T2DM with BMI≥28·0 kg/m2, simple enlarged WC and simple disorders of lipid metabolism showed an increasing tendency (aOR=1·31, 1·75 and 2·32).
The prevalence of HTGW and T2DM has reached an alarming level among rural Chinese people, and HTGW is a significant risk factor for T2DM.
Dairy cows with fatty liver or ketosis display decreased insulin sensitivity and defects in the insulin receptor substrate (IRS)/PI3K/AKT signaling pathway. Phosphatase and tensin homolog (PTEN) is a well-known tumor suppressor and also a negative regulator of insulin signaling and peripheral insulin sensitivity. We investigated the hypothesis that PTEN may affect the insulin pathway-mediated hepatic glucose and lipid metabolism in dairy cows. Adenovirus vectors that over-express and silence PTEN were constructed, and then transfected into hepatocytes isolated from calves to investigate the effect of PTEN on PI3K/AKT signaling pathway. PTEN silencing increased the phosphorylation of AKT and the expression of PI3K but decreased the phosphorylation of IRS1, which increased the phosphorylation levels of glycogen synthase kinase-3β (GSK-3β) and expression of sterol regulatory element-binding protein-1c (SREBP-1c). Increased GSK-3β phosphorylation further up-regulated expression of the key enzymes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6-Pase) involved in gluconeogenesis. Furthermore, the expression of SREBP-1c target gene fatty acid synthase (FAS) also increased significantly. We further showed that PTEN over-expression could reverse the above results. PTEN negatively regulates the enzymes involved in hepatic gluconeogenesis and lipid synthesis, which suggests that PTEN may be a therapeutic target for ketosis and fatty liver in dairy cows.
This paper presents new LA-ICP-MS zircon U–Pb chronology, whole-rock geochemical and zircon Hf isotopic data for the felsic lavas of the Huili Group from the southwestern Yangtze Block. LA-ICP-MS zircon U–Pb dating shows that these rocks were emplaced in Late Mesoproterozoic time (∼1028 to 1019 Ma). Relative to typical I-type and S-type granitoids, all the samples are characterized by low Sr and Eu, and high high-field-strength element contents, high TFeO/MgO, enriched rare earth element compositions and negative Eu anomalies, indicating that they share the geochemical signatures of A-type granitoid. They can be further divided into two groups: Group I and Group II. Group I are A1-type felsic rocks and were produced by fractional crystallization of alkaline basaltic magmas. The Group II felsic lavas belong to the A2-type and were derived by partial melting of a crustal source with mixing of mantle-derived magmas. Both Group I and Group II felsic lavas may erupt in a continental back-arc setting. The coexistence of A1- and A2-type rocks in the southwestern Yangtze Block suggests that they can occur in the same tectonic setting.
The aim of this study was to investigate the in vivo degradation mechanism and the mechanical properties of poly(lactide-co-glycolide)/beta-tricalcium phosphate (PLGA/β-TCP) composite anchors. Anchors composed of PLGA and β-TCP were implanted in the dorsal subcutaneous tissue of beagle dogs for 6, 12, 16, and 26 weeks. The degradation of the materials was evaluated by measuring the changes in thermal behavior, crystallinity, and mechanical properties. Scanning electron microscope (SEM) was used to observe the surface and longitudinal section of the material. The evaluation of mechanical strength retention and degradation properties suggest that the addition of β-TCP particles efficiently enhances their mechanical properties and thermal characteristics and delays their degradation rate. By analyzing the results of SEM, X-ray diffraction, and differential scanning calorimetry, we can infer that after 12 weeks, the connection between β-TCP and PLGA becomes less compact, which accelerates the decline of mechanical strength.
Laser-driven magnetic reconnection (LDMR) occurring with self-generated B fields has been experimentally and theoretically studied extensively, where strong B fields of more than megagauss are spontaneously generated in high-power laser–plasma interactions, which are located on the target surface and produced by non-parallel temperature and density gradients of expanding plasmas. For properties of the short-lived and strong B fields in laser plasmas, LDMR opened up a new territory in a parameter regime that has never been exploited before. Here we review the recent results of LDMR taking place in both high and low plasma beta environments. We aim to understand the basic physics processes of magnetic reconnection, such as particle accelerations, scale of the diffusion region, and guide field effects. Some applications of experimental results are also given especially for space and solar plasmas.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
In the above publication by Chen et al. (2017), the authors neglected to include that Dr. Zhang was supported by the 111 Project (Grant Number B16031) as part of their financial support and conflicts of interest. The complete corrected conflicts of interest section is provided below:
The authors report grants from the National Natural Science Foundation of China, grants from the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period, and grants from the Key Discipline in Shanghai during the conduct of the study. Dr. Zhang was supported by the 111 Project (Grant Number B16031).
In this paper the asymmetric shock reflection configurations in two-dimensional steady flows have been studied theoretically. For an overall Mach reflection, it is found that the horizontal distance between both triple points in the Mach stem is related to the angles of two slip streams. Based on the features of the converging stream tube, several assumptions are put forward to perform better the wave configurations near the slip streams. Therefore, we present an analytical model here to describe the asymmetric overall Mach reflection configurations which agrees well with the computational and experimental results.
A coupled mathematical system of four quasi-linear partial differential equations and the initial-boundary value conditions is presented to interpret transient behavior of three dimensional semiconductor device with heat conduction. The electric potential is defined by an elliptic equation, the electron and hole concentrations are determined by convection-dominated diffusion equations and the temperature is interpreted by a heat conduction equation. A mixed finite element approximation is used to get the electric field potential and one order of computational accuracy is improved. Two concentration equations and the heat conduction equation are solved by a fractional step scheme modified by a second-order upwind difference method, which can overcome numerical oscillation, dispersion and computational complexity. This changes the computation of a three dimensional problem into three successive computations of one-dimensional problem where the method of speedup is used and the computational work is greatly shortened. An optimal second-order error estimate in L2 norm is derived by prior estimate theory and other special techniques of partial differential equations. This type of parallel method is important in numerical analysis and is most valuable in numerical application of semiconductor device and it can successfully solve this international famous problem.
Objectives: The aim of this study was to evaluate the universal newborn hearing screening (UNHS) and intervention program in Shanghai, China.
Methods: This study included the quantitative analyses of the UNHS-Shanghai database in 2002–12 and qualitative assessment of the program. The Otoacoustic Emissions and the Automated Auditory Brainstem Evoked Responses tests were conducted in screening. The costs and benefits were calculated based on the number of participants in each stage. The short-term and long-term periods were defined as from birth to 15 years of age or to death (82-year-olds), respectively. Sensitivity analyses were conducted.
Results: A total 1,574,380 newborns were included, representing 93.6 percent of all eligible babies in Shanghai during the study period. The prevalence of newborn hearing loss was 1.66‰. The short-term/long-term program costs were ¥488.5 million (US$75.52 million)/¥1.08 billion (US$167.12 million), and the short-term/long-term program benefit was ¥980.1 million (US$151.53 million)/¥8.13 billion (US$1.26 billion). The program benefit was greater than its cost if the proportion of hearing-loss children enrolled in regular schools was no less than 41.4 percent of all hearing impaired children, as well as if the wage growth rate ranged from 3 percent to 8 percent. Qualitative results also suggested that stakeholders strongly supported this program.
Conclusions: The universal newborn hearing screening and intervention program in Shanghai is justified in terms of the resource input in the long run, although there is still room for further improvement with respect to educational rehabilitation and a better infrastructure system.
From the IRAS catalogue we selected 10,001 young infrared (IR) sources which lie within the galactic plane. Their IR flux integrated over ±5° in latitude shows maxima at galactic longitudes l = 80°, 60°, 50°, 35°, −27°, −54°, and −74°, which directions are interpreted as tangents to the spiral arms. The resulting spiral arm pattern is nearly identical with the arms derived from observations of O and B stars.
Wake vortex evolution of a square cylinder with a slot synthetic jet issuing from the cylinder’s rear surface has been experimentally investigated using the time-resolved particle image velocimetry technique. The Reynolds number based on the side length of the square cylinder is
. The excitation frequency normalized by the natural shedding frequency
varies from 0 to 6 at the dimensionless stroke length
. The distributions of the time-averaged Reynolds stresses present significant differences as the excitation frequency increases. With control, the mean streamwise velocity deficit of the wake recovers more quickly in comparison with the natural case, and the vertical velocity fluctuation intensity becomes weaker. Moreover, a drag reduction can be achieved for the control cases, especially, for
, a thrust instead of drag reduction can be obtained. The profiles of the mean streamwise velocity tend to have jet-like distributions. The wake vortex dynamics and its evolution with the excitation frequency are revealed. (i) For the low excitation frequency cases (
, 1, 2), no significant changes in the dominant frequency and the spanwise vortex structures are observed in comparison with the natural case. (ii) For the moderate excitation frequency case (
), the wake vortex shedding frequency is locked on half of the control frequency. In this case, the shear layer is divided into two parts by the synthetic jet vortex, and the wake vortices with smaller scales still shed asymmetrically and appear closer to the square cylinder. (iii) For the high excitation frequency case (
), the flow is governed by the synthetic jet. As a result of strong perturbations of the synthetic jet, the wake vortex shedding becomes symmetric with the shedding frequency consistent with the control frequency. And the separation is suppressed effectively. The different control effects of the slot synthetic jet on a square cylinder and a circular cylinder are also compared in detail. Generally speaking, the circular cylinder is easier to be controlled due to its non-fixed separation points.
We report here first results on the bulk soil organic carbon (SOC), apparent radiocarbon ages and δ13C characteristics of the tropical and subtropical forest soil in Dinghushan Biosphere Reserve (DHSBR). The forest oxisol in Dinghushan has developed during the Holocene. The δ13C variation curves in all three profiles may be divided into two sections. The upper section from 0 to 40 cm has δ13C values varying from −27.4 to −24.1‰, −27.5 to −22.2‰, and −24.4 to −20.1‰. in the Wukesong, Qingyunsi and Kengkou profiles, respectively. The lower section, including the 40–160 cm horizons, has a uniform δ13C. The mean δ13C values of the soil organic carbon could be used not only to discriminate between C3 and C4 plants, but also to distinguish between coniferous and broad-leaf plants.
While radiocarbon is widely applied in dating ancient samples, recent studies reveal that 14C concentrations in modern samples can also yield precise ages due to the atmospheric testing of thermonuclear devices between 1950 and 1963. 14C concentrations in both enamel and organic matter of 13 teeth from 2 areas in China were examined to evaluate and improve this method of forensic investigation. Choosing enamel near the cervix of the tooth can reduce the error caused by the difference between the sample formation time and whole enamel formation time because tooth enamel formations take a long time to complete. A proper regional data set will be helpful to get an accurate result when calculating the age of the sample (T1) by the CALIBomb program. By subtracting the enamel formation time (t), the birth date of an individual (T2) can be confirmed by enamel F14C from 2 teeth formed at different ages. Calculated enamel formation dates by 14C concentration are basically consistent with corresponding actual values, with a mean error of 1.9 yr for all results and 0.2 yr for the samples formed after AD 1960. This method is more effective for dating samples completed after AD 1960. We also found that 14C concentrations in organic matter of tooth roots are much lower than atmospheric concentrations in root formation years, suggesting that the organic material keeps turning over even after tooth formation is complete. This might be a potential tool for identification of death age to extract a proper component for 14C dating. We also observed that δ13C values between hydroxyapatite and organic matter indicate that isotopic fractionation during the biomineralization is 8–9%‰ more positive in mineral fractions than in organic matter.