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The AIMTB rapid test assay is an emerging test, which adopted a fluorescence immunochromatographic assay to measure interferon-γ (IFN-γ) production following stimulation of effector memory T cells in whole blood by mycobacterial proteins. The aim of this article was to explore the ability of AIMTB rapid test assay in detecting Mycobacterium tuberculosis (MTB) infection compared with the widely applied QuantiFERON-TB Gold Plus (QFT-Plus) test among rural doctors in China. In total, 511 participants were included in the survey. The concordance between the QFT-Plus test and the AIMTB rapid test assay was 94.47% with a Cohen’s kappa coefficient (κ) of 0.84 (95% CI, 0.79–0.90). Improved concordance between the two tests was observed in males and in participants with 26 or more years of service as rural doctors. The quantitative values of the QFT-Plus test was higher in individuals with a result of QFT-Plus-/AIMTB+ as compared to those with a result of QFT-Plus-/AIMTB- (p < 0.001). Overall, our study found that there was an excellent consistency between the AIMTB rapid test assay and the QFT-Plus test in a Chinese population. As the AIMTB rapid test assay is fast and easy to operate, it has the potential to improve latent tuberculosis infection testing and treatment at the community level in resource-limited settings.
The role of Mn oxide in the abiotic formation of humic substances has been well demonstrated. However, information on the effect of crystal structure and surface-chemical characteristics of Mn oxide on this process is limited. In the present study, hexagonal and triclinic birnessites, synthesized in acidic and alkali media, were used to study the influence of the crystal-structure properties of birnessites on the oxidative polymerization of hydroquinone and to elucidate the catalytic mechanism of birnessites in the abiotic formation of humic-like polymers in hydroquinone-birnessite systems. The intermediate and final products formed in solution and solid-residue phases were identified by UV/Visible spectroscopy, atomic absorption spectrometry, Fourier-transform infrared spectroscopy, X-ray diffraction, solid-phase microextraction-gaschromatography-mas ss pectrometry, ion chromatography, and ultrafiltration. The degree of oxidative polymerization of hydroquinone wasenhanced with increase in the interlayer hydrated H+, the average oxidation state (AOS), and the specific surface area of birnessites. The nature of the functional groups of the humic-like polymers formed was, however, almost identical when hydroquinone was catalyzed by hexagonal and triclinic birnessites with similar AOS of Mn. The results indicated that crystal structure and surface-chemistry characteristics have significant influence on the oxidative activity of birnessites and the degree of polymerization of hydroquinone, but have little effect on the abiotic formation mechanism of humic-like polymers. The proposed oxidative polymerization pathway for hydroquinone isthat, asit approachesthe birnessite, it formsp recursor surface complexes. Asa strong oxidant, birnessite accepts an electron from hydroquinone, which is oxidized to 1,4-benzoquinone. The coupling, cleavage, polymerization, and decarboxylation reactionsaccompany the generation of 1,4-benzoquinone, lead to the release of CO2 and carboxylic acid fragments, the generation of rhodochrosite, and the ultimate formation of humic-like polymers. These findings are of fundamental significance in understanding the catalytic role of birnessite and the mechanism for the abiotic formation of humic substances in nature.
Fast neutron absorption spectroscopy is widely used in the study of nuclear structure and element analysis. However, due to the traditional neutron source pulse duration being of the order of nanoseconds, it is difficult to obtain a high-resolution absorption spectrum. Thus, we present a method of ultrahigh energy-resolution absorption spectroscopy via a high repetition rate, picosecond duration pulsed neutron source driven by a terawatt laser. The technology of single neutron count is used, which results in easily distinguishing the width of approximately 20 keV at 2 MeV and an asymmetric shape of the neutron absorption peak. The absorption spectroscopy based on a laser neutron source has one order of magnitude higher energy-resolution power than the state-of-the-art traditional neutron sources, which could be of benefit for precisely measuring nuclear structure data.
Sichuan cuisine was previously fitted into the Chinese Heart-Healthy Diet (CHH) trial to verify the antihypertensive effect. Whether the modified Sichuan diet lessens cardiovascular disease (CVD) is not fully explored. We aimed to estimate the effects of the Sichuan version of CHH diet (CHH diet-SC) on the 10-year risk of CVD and vascular age. A single-blinded randomised controlled feeding trial was conducted. General CVD prediction model was used in manners of intention-to-treat and per-protocol set. After a 7-d run-in period, fifty-three participants with pre- and grade I hypertension from local communities were randomised and provided with either CHH diet-SC (n 27) or a control diet (n 26) for 4 weeks. Mean absolute and relative estimated CVD risks were reduced by 4·5 % and 27·9 % in the CHH diet-SC group, and the between-group relative risk reduction was 19·5 % (P < 0·001) using linear mixed-effects models. The sensitivity analysis with datasets and models showed consistent results, and pre-specified factors were not associated with the intervention effects. The vascular age of CHH-SC group was theoretically 4·4 years younger than that of the control group after intervention. Compared with a typical diet, adopting the CHH diet-SC over 1 month significantly reduced 10-year CVD risks and vascular ages among local adults with mild hypertension.
In vitro rearing of honey bee larvae is ideal for bioassay studies; no honey bee stable cell lines are available. Inconsistency of internal development staging of reared larvae and a susceptibility to contamination are common problems encountered. Standardized protocols on rearing larvae in vitro to make the larvae growth and development more similar to that of natural colonies are necessary to ensure the accuracy of experimental results and promote honey bee research as a model organism. Here, we concluded that when larval fasting weight was >160 mg, the time point of gut emptying can be defined as the critical point separating the larval and prepupal stages. In this way, we can conduct precise studies on the prepupal stage, such as organ remodeling during metamorphosis. Simultaneously, we further verified that recombinant AccApidaecin in genetic engineered bacteria added to the larval diet upregulated antibacterial peptide gene expression, and did not stimulate the stress response in larvae, nor did it affect the pupation rate or eclosion rate. This demonstrated that feeding recombinant AccApidaecin can enhance the individual antibacterial ability at the molecular level.
We aimed to examine the association between the quantity and quality of dietary fat in early pregnancy and gestational diabetes mellitus (GDM) risk. In total, 1477 singleton pregnant women were included from Sichuan Provincial Hospital for Women and Children, Southwest China. Dietary information was collected by a 3-d 24-h dietary recall. GDM was diagnosed based on the results of a 75-g, 2-h oral glucose tolerance test at 24–28 gestational weeks. Log-binomial models were used to estimate relative risks (RR) and 95% CI. The results showed that total fat intake was positively associated with GDM risk (Q4 v. Q1: RR = 1·40; 95 % CI 1·11, 1·76; Ptrend = 0·001). This association was also observed for the intakes of animal fat and vegetable fat. After stratified by total fat intake (< 30 %E v. ≥ 30 %E), the higher animal fat intake was associated with higher GDM risk in the high-fat group, but the moderate animal fat intake was associated with reduced risk of GDM (T2 v. T1: RR = 0·65; 95 % CI 0·45, 0·96) in the normal-fat group. Vegetable fat intake was positively associated with GDM risk in the high-fat group but not in the normal-fat group. No association between fatty acids intakes and GDM risk was found. In conclusion, total fat, animal and vegetable fat intakes were positively associated with GDM risk, respectively. Whereas when total fat intake was not excessive, higher intakes of animal and vegetable fat were likely irrelevant with increased GDM risk, even the moderate animal fat intake could be linked to lower GDM risk.
The oxidation behavior of the selective laser melting (SLM)–fabricated Inconel 718 was investigated through isothermal oxidation testing at 650 °C for 500 h and compared with that of the as-cast and as-forged specimens at the same testing conditions. The effect of microstructure and surface roughness on the oxidation behavior of the SLM-fabricated, as-cast, and as-forged Inconel 718 specimens was examined. The result shows that Inconel 718 fabricated by SLM with the unique layer structure exhibited a better resistance to the 500 h oxidation at 650 °C compared with as-cast and as-forged 718 with coarse dendritic structure and uniform equiaxed grain microstructure, respectively. The influence of the surface roughness on the long-time oxidation resistance of SLM specimens is not pronounced compared with that of as-cast and as-forged specimens. The tiny dendrites instead of grain boundaries are a major influencing factor for the oxidation process of SLM specimens. The surface roughness has more evident influence on the oxidation resistance of as-forged specimens than that of the as-cast ones subjected to the 500 h oxidation at 650 °C.
Indoor positioning systems have received increasing attention for supporting location-based services in indoor environments. Wi-Fi based indoor localisation has become attractive due to its extensive distribution and low cost properties. IEEE 802.11-2016 now includes a Wi-Fi Fine Time Measurement (FTM) protocol which can be used for Wi-Fi ranging between intelligent terminal and Wi-Fi access point. This paper introduces a framework of Wi-Fi FTM data acquisition and processing that can be used for indoor localisation. We analyse the main factors that affect the accuracy of Wi-Fi ranging and propose a calibration, filtering and modelling algorithm that can effectively reduce the ranging error caused by clock deviation, non-line-of-sight (NLOS) and multipath propagation. Experimental results show that the proposed calibration and filtering method is able to achieve metre-level ranging accuracy in case of line-of-sight by using large bandwidth. Estimation results also show that the proposed Wi-Fi ranging model provides an accurate ranging performance in NLOS and multipath contained indoor environment; the final positioning error is less than 2·2 m with a stable output frequency of 3 Hz.
Residual strain often occurs in metal when it was subjected to the tension load, random vibration, or high impact. The mild steel was selected as the research object, and the feasibility of using nonlinear ultrasonic technique to characterize the residual strain was investigated in this paper. First, the mild steel specimens were stretched to several different kinds of stress, then the nonlinear effect as well as the microstrain of each sample was measured. The results indicate that the microstrain increases with increasing applied stress and reaches a maximum value of about 0.036% as the tensile stress increases to the elastic limit. Compared with the original specimen, the nonlinear parameter of tensile specimen gradually increased within the elastic limit. This result reveals that the variation of nonlinear parameter was related to microstrain in mild steel, because the microstructure observation demonstrated that the dislocation structure was basically unchanged within the elastic limit. This research indicates that the nonlinear ultrasonic method has the promising potential to characterize the microstrain in metals.
Excited by the great success of metal halide perovskites in the optoelectronic and electro-optic fields and the interesting emerging physics (Rashba splitting, quantum anomalous hall effect) of layered metal halides, metal halides have recently been attracting significant attentions from both research and industrial communities. It is shown that most progresses have been made when these materials are obtained at reduced dimensions. Among several growth methods, vapor phase epitaxy has been demonstrated with a universal control on morphology, phase, and composition. We thus believe that a thorough understanding on the physical properties and on the growth of general metal halide compounds at reduced dimensions would be very beneficial in the study of recent perovskites and layered metal halide materials. This review covers the physical properties of most studied metal halides and summarizes the vapor phase epitaxial growth knowledge collected in the past century. We hope that this comprehensive review could be helpful in designing new physical properties and in planning growth parameters for emerging metal halide crystals.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
The late Quaternary sedimentary sequence in the northwestern part of the Sichuan Basin consists of five lithological units and with increasing depth include the: Chengdu Clay; Brown Clay; Red Clay; Sandy Silt; and basal Muddy Gravel. The genesis, provenance and age of the sediments, as well as the possible presence of hiatuses within this sequence are debated. Measurements of grain-size, magnetic susceptibility, quartz content, quartz δ18O values, element composition, and Sr–Nd isotopic concentrations of samples from a typical sedimentary sequence in the area provides new insights into the genesis and history of the sequence. The new data confirm that the sediments in study site are alluvial–aeolian in origin, with basal alluvial deposits overlain by aeolian deposits. Like the uppermost Chengdu Clay, the underlying Brown Clay and Red Clay are aeolian in origin. In contrast, the Silty Sand, like the basal Muddy Gravel, is an alluvial deposit and not an aeolian deposit as previously thought. Moreover, the succession of the aeolian deposits very likely contains two significant sedimentary hiatuses. Sedimentological analysis demonstrates that the source materials for the aeolian deposits in the northwestern part of the Sichuan Basin and those on the eastern Tibetan Plateau are different. Furthermore, the loess deposits on the eastern Tibetan Plateau are derived from heterogeneous local sources.
The spread of buffalobur in China poses a serious threat to existing ecosystems, and control and eradication of this species have become increasingly important. Studies were carried out to ascertain the seed production, morphological characterization, dormancy behavior, and methods for breaking dormancy of buffalobur. The results showed that a single buffalobur plant could produce 1,600 to 43,800 seeds with an average weight of 3.0 mg. Average seed length, width, and thickness were 2.5, 2.0, and 1.0 mm, respectively. Newly ripened buffalobur seeds were innately dormant and exhibited combinational dormancy, which involves a hard seed coat (physical dormancy, PY), a partial dormant embryo (physiological dormancy, PD), and a dark requirement to germinate. PY of buffalobur seeds could be broken by dehusking or acid scarification by 14 M H2SO4 for 15 min, with germination rates of 55 or 50%, respectively. PD was effectively broken by KNO3 or gibberellic acid (GA3). The optimum concentration for KNO3 was between 20 and 40 mM, which resulted in over 70% seed germination. When presoaked with GA3 at 30 C in dark for 24 h, maximum germination (> 98%) was obtained at 2.4 mM, the corresponding germination speed (85%) and germination index (16) were also highest at this concentration. Synergistic effects were observed in seed germination when H2SO4 and GA3 were combined. The most rapid and effective combination in breaking dormancy was when the seeds were immersed in H2SO4 (14 M) for 20 min and presoaked with 2.4 mM GA3 for 24 h. Germination index for this combination was over 35, and 95% of the seeds germinated within 7 d. Knowledge gained in this study will be useful in increasing germination of buffalobur and facilitating further laboratory studies.
The thermal properties of organic membranes attract much attention due to the fact that heat dissipation in electronic devices limits their functionality and reliability. Here, we enhance the thermal conductivity of polyvinyl alcohol (PVA) membrane using nano-fibers fabricated by electrospinning. Measured by the 3-Omega method, the results show that the effective thermal conductivity of the electrospinning membranes (with/without Cu nanoparticles) are as high as 0.7 W/m-K at room temperature which is as twice as the value of thermal conductivity of amorphous spin-coated PVA membrane (0.35 W/m-K). The mechanism of enhancement are that, compared with amorphous membrane, the phonon scattering is attenuated and the crystallinity is improved in the electrospinning process. Our studies bring new insights in designing new kind of membrane with high thermal conductivity.
SG-III laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%. We review the laser system and introduce the SG-III laser performance here.
Accumulating evidence suggests that altered immunity contributes to the
development of major depressive disorder (MDD).
Aims
To examine whether complement factor H (CFH), a regulator of activation
of the alternative pathway of the complement cascade, confers
susceptibility to MDD.
Method
Expression analyses were tested in 53 unmedicated people with MDD and 55
healthy controls. A two-stage genetic association analysis was performed
in 3323 Han Chinese with or without MDD. Potential associations between
CFH single nucleotide polymorphisms and age at MDD
onset were evaluated.
Results
CFH levels were significantly lower in the MDD group at
both protein and mRNA levels (P = 0.009 and
P = 0.014 respectively). A regulatory variant in the
CFH gene, rs1061170, showed statistically significant
genotypic and allelic differences between the MDD and control groups
(genotypic P = 0.0005, allelic P =
0.0001). Kaplan–Meier survival analysis showed that age at onset of MDD
was significantly associated with the C allele of
rs1061170 (log rank statistic χ2 = 6.82, P =
0.009). The C-allele carriers had a younger age at onset
of MDD (22.2 years, s.d. = 4.0) than those without the C
allele (23.6 years, s.d. = 4.3).
Conclusions
CFH is likely to play an important role in the
development of MDD. rs1061170 has an important effect on age at onset of
MDD in Han Chinese and may therefore be related to early pathogenesis of
MDD, although further study is needed.
Mussels are typical macrofouling organisms in the world. In this study, the interaction between the settlement of Mytilus coruscus plantigrades and bacterial community on coloured substrata was determined. Bacterial communities in biofilms developed on seven coloured substrata were analysed by Illumina Miseq sequencing. The mussel settlement response to coloured substrata with no biofilms was also examined. Flavobacteria, Alphaproteobacteria and Gammaproteobacteria were the first, second and third most dominant groups in seven biofilm samples. The results suggest that the inducing activities of these biofilms on plantigrade settlement varied with coloured substrata and the lowest percentage of settlement was observed on biofilms on the green substratum. High-throughput sequencing showed that bacterial community in biofilms also changed with the substratum colour. No significant difference in the inducing activity on plantigrade settlement was observed between the coloured substrata with no biofilms. Thus, difference in plantigrade settlement response may be correlated to the changes in bacterial community on coloured substrata. This finding extends current knowledge of interaction among mussel settlement and bacterial community variability.
To examine the vitamin D status, SNP of the vitamin D receptor gene (VDR) and the effects of vitamin D supplementation on parathyroid hormone and insulin secretion in adult males with obesity or normal weight in a subtropical Chinese city.
Design
An intervention trial.
Setting
Shenzhen City, Guangdong Province, China.
Subjects
From a cross-sectional survey conducted from June to July, eighty-two normal-weight and ninety-nine obese males (18–69 years) were screened to analyse their vitamin D status and for five SNP of VDR. From these individuals, in the same season of a different year, obese and normal-weight male volunteers (twenty-one per group) were included for an intervention trial with oral vitamin D supplementation at 1250 µg/week for 8 weeks.
Results
For the survey, there was no significant difference (P>0·05) in baseline circulating 25-hydroxyvitamin D concentrations or in the percentages of participants in different categories of vitamin D status between the two groups. The VDR SNP, rs3782905, was significantly associated with obesity (P=0·043), but none of the examined SNP were correlated with serum 25-hydroxyvitamin D when adjusted for age, BMI and study group. After vitamin D supplementation, serum 25-hydroxyvitamin D concentration, hypersecretions of parathyroid hormone and insulin, and insulin resistance in the obese were changed beneficially (P<0·05); however, the increase in serum 25-hydroxyvitamin D was less than that of the normal-weight men.
Conclusions
For obese and normal-weight men of subtropical China, the summer baseline vitamin D status was similar. However, oral vitamin D supplementation revealed a decreased bioavailability of vitamin D in obese men and ameliorated their hypersecretion of parathyroid hormone and insulin resistance.
The highly ordered mesoporous chromium–alumina catalysts (denoted as OMCA(x)) with different nAl/nCr ratios of 10 and 20 have been successfully synthesized via an evaporation-induced self-assembly (EISA) pathway associated with thermal treatment and were applied to the liquid phase oxidation of cyclohexane with hydrogen peroxide (H2O2) as an oxidant. For comparison studies, a chromium catalyst with the nAl/nCr ratio of 10 supported on an ordered mesoporous alumina support [denoted as Cr/OMA(10)] was also prepared by an incipient wetness impregnation (IWI) method. Although both kinds of catalysts retained a unidimensionally ordered mesoporous structure, textural properties of the catalysts were significantly affected by the preparation method. The characteristic results from XRD, N2 adsorption, TEM, UV-Vis, 27Al MNS NMR, and H2-TPR showed that the OMCA(x) catalysts exhibited much more highly ordered hexagonal mesostructure, narrower pore-size distribution, higher Brunauer-Emmett-Teller surface area and pore volume, and more homogeneous distribution of Cr species in mesoporous alumina framework in the form of tetrahedrally coordinated hexavalent Cr-oxide moieties than those of Cr/OMA(10) synthesized by an IWI method. In addition, in comparison with Cr/OMA(10), OMCA(x) catalysts showed higher catalytic activity and stability for the liquid phase oxidation of cyclohexane.