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The first case of 2019-nCoV pneumonia infection occurred in Wuhan, Hubei Province, South China Seafood Market in December 2019. As a group with a high probability of infection, health workers are faced with a certain degree of psychological challenges in the process of facing the epidemic. This study attempts to evaluate the impact of 2019-nCoV outbreak on the psychological state of Chinese health workers and to explore the influencing factors. During the period from 31 January 2020 to 4 February 2020, the ‘Questionnaire Star’ electronic questionnaire system was used to collect data. The 2019-nCoV impact questionnaire and The Impact of Event Scale (IES) were used to check the psychological status of health workers in China. A total of 442 valid data were collected in this study. Seventy-four (16.7%) male and 368 (83.3%) female individuals participated in this study. The average score of high arousal dimension was 5.15 (s.d. = 4.71), and the median score was 4.0 (IQR 2.0, 7.0). The average score of IES was 15.26 (s.d. = 11.23), and the median score was 13.5 (IQR 7.0, 21.0). Multiple regression analysis showed that there were critical statistical differences in high arousal scores among different gender groups (male 3.0 vs. female 5.0, P = 0.075). Whether being quarantined had significant statistical differences of IES scores (being quarantined 16.0 vs. not being quarantined 13.0, P = 0.021). The overall impact of the 2019-nCoV outbreak on health workers is at a mild level. Chinese health workers have good psychological coping ability in the face of public health emergencies.
Many clinical trials showed favorable effects of high-doses supplemental n-3 polyunsaturated fatty acids (PUFA) on cardio-metabolic risk factors. However, limited studies examined the prospective associations of circulating n-3 PUFA with body fat and its distribution, metabolic syndrome (MS), carotid atherosclerosis, and nonalcoholic fatty liver disease (NAFLD) in subjects with habitual diets containing low levels of n-3 PUFA.
Materials and Methods
This community-based prospective study enrolled 4048 participants (40–75 years) at baseline (2008–2010, 2013) from Guangzhou, China. They were followed-up approximately once every 3 years. Fatty acids in erythrocyte membranes were measured at baseline. We determined metabolic syndrome factors, body fat by DXA scanning, carotid intima-media thickness (IMT) and NAFLD by ultrasound at the visits. General information, anthropometric indices, habitual dietary intake and other covariates were assessed at each visit.
Among the total 4048 subjects, 3075 and 2671 subjects had erythrocyte n-3 PUFA data and completed the first and second follow-ups. Generally, erythrocyte n-3 PUFA were favorably associated with body fat (particularly at abdomen) and its changes, and with the presence and incidence of MS, type 2 diabetes, carotid IMT thickening. The participants with the highest (vs lowest) quartile of n-3 PUFA were associated with -5.81% fat mass (p < 0.001) and -2.11% of fat mass change at the abdomen (Android) area. The adjusted hazards ratios (95% CI) for the highest (vs. lowest) group were 0.74 (0.61, 0.89) (total n-3 PUFA), 0.71 (0.59, 0.86) (docosahexaenoic acid, DHA), 0.78 (0.65, 0.95) (docosapentaenoic acid, DPA), 1.96 (1.60, 2.40) (gamma-linolenic acid, GLA) for MS; 0.70(0.55, 0.90) (total n-3 PUFA), 0.67(0.52,0.87) (DHA) and 0.73(0.57,0.93) (DPA) for bifurcation IMT thickening, 0.57(0.38, 0.86) (eicosapentaenoic acid, EPA) and 0.63 (0.41, 0.95) (DPA) for type 2 diabetes, and 1.18 (1.09, 1.33) (DHA) for alleviated NAFLD. Both higher levels of total and individual marine n-3 PUFAs (DHA, EPA and DPA) were associated with lower blood pressure at baseline and lower changes in diastolic and systolic blood pressure over the follow-up period. Plant n-3 PUFA (α-linolenic acid, ALA) largely had less significant association with the above-mentioned indices as compared with marine n-3 PUFAs.
Higher proportions of erythrocyte n-3 PUFA (particularly marine sources) was associated with lower body fat, blood pressure and their changes, and lower risks of MS, type 2 diabetes and bifurcation IMT thickening, but higher chance of alleviated NAFLD in middle-aged and older adults.
The collective hydrodynamics in fish schools and bird flocks, which includes self-organization of multiple dynamic bodies, is complex and lacks sufficient exploration. In this paper, we study the performance of multiple self-propelled foils in tandem formation, whose flapping motions are asynchronous with a phase difference. It is shown that a compact formation, in which all of the foils perform like a complete anguilliform swimmer, can be spontaneously formed by multiple foils via hydrodynamic interactions. Both velocity enhancement and energy saving can be achieved by multiple foils in anguilliform-like swimming. Furthermore, such anguilliform-like swimming behaviour can be observed over a wide range of parameters, including the number of foils, the phase difference, the initial distance, the heaving amplitude and the pitching amplitude. The results obtained here may provide some light on understanding the self-organization behaviour of biological collectives.
To investigate the hypothesis that folic acid supplementation and dietary folate intake before conception and during pregnancy reduce the risk of small for gestational age (SGA) and to examine the joint effect of folic acid supplementation and dietary folate intake on the risk of SGA.
Participants were interviewed by trained study interviewers using a standardized and structured questionnaire. Information on birth outcomes and maternal complications was abstracted from medical records and dietary information was collected via a semi-quantitative FFQ before conception and during pregnancy.
A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital.
Women (n 8758) and their children enrolled in the study.
Folic acid supplementation was associated with a reduced risk of SGA (OR = 0·72, 95 % CI 0·60, 0·86), with the reduced risk seen mainly for SGA at ≥37 weeks of gestational age (OR = 0·70, 95 % CI 0·58, 0·85) and nulliparous SGA (OR = 0·67, 95 % CI 0·54, 0·84). There was no significant association between dietary folate intake and SGA risk.
Our study suggested that folic acid supplementation was associated with a reduced risk of SGA and the risk varied by preterm status and parity.
This study examines the impact of employability on turnover intention by differentiating internal and external employability, and considering the possible moderating roles of perceived organizational support (POS) and career orientation. Using a sample of 411 responses to a two-wave questionnaire survey generated from six cities in China, we find that external employability positively influenced turnover intention, but internal employability negatively influenced turnover intention. The results also indicate that POS had a positive moderating effect only on the relationship between external employability and turnover intention. Furthermore, for employees with disengaged career orientation, external employability exerts a strong impact on turnover intention. This study adds to the limited research empirically linking employability and turnover intention, whereas the findings can be used by HRM practitioners to factor in organizational support and career orientation initiatives that improve the retention of employees with high external employability.
Previous studies have shown that the Dietary Approaches to Stop Hypertension (DASH) diet might contribute to managing risk factors of non-alcoholic fatty liver disease (NAFLD), but evidence is limited. We examined the association of DASH diet score (DASH-DS) with NAFLD, as well as the intermediary effects of serum retinol-binding protein-4 (RBP4), serum high-sensitivity C-reactive protein (hs-CRP), serum TAG, homeostasis model assessment of insulin resistance (HOMA-IR) and BMI.
We performed a cross-sectional analysis of a population-based cohort study. Dietary data and lifestyle factors were assessed by face-to-face interviews and the DASH-DS was then calculated. We assessed serum RBP4, hs-CRP and TAG and calculated HOMA-IR. The presence and degree of NAFLD were determined by abdominal sonography.
Guangzhou Nutrition and Health Study participants, aged 40–75 years at baseline (n 3051).
After adjusting for potential covariates, we found an inverse association between DASH-DS and the presence of NAFLD (Ptrend = 0·009). The OR (95 % CI) of NAFLD for quintiles 2–5 were 0·78 (0·62, 0·98), 0·74 (0·59, 0·94), 0·69 (0·55, 0·86) and 0·77 (0·61, 0·97), respectively. Path analyses indicated that a higher DASH-DS was associated with lower serum RBP4, hs-CRP, TAG, HOMA-IR and BMI, which were positively associated with the degree of NAFLD.
Adherence to the DASH diet was independently associated with a marked lower prevalence of NAFLD in Chinese adults, especially in women and those without abdominal obesity, and might be mediated by reducing RBP4, hs-CRP, TAG, HOMA-IR and BMI.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
We report on a high-repetition-rate, high-power continuously pumped Nd:GdVO4 regenerative amplifier. Numerical simulations successfully pinpoint the optimum working point free of bifurcation instability with simultaneous efficient energy extraction. At a repetition rate of 100 kHz, a maximum output power of 23 W was obtained with a pulse duration of 27 ps, corresponding to a pulse energy of
. The system displayed an outstanding stability with a root mean square power noise as low as 0.3%. The geometry of the optical resonator and the pumping scheme enhanced output power in the
mode with a single bulk crystal. Accordingly, nearly diffraction-limited beam quality was produced with
at full pump power.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
Babesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates of Babesia microti infection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution of Babesia in its endemic regions is largely unknown. In this study, we cataloged 1672 small wild rodents, comprising 4 orders, from nine areas in western Yunnan province between 2009 and 2011. Babesia microti DNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species included Apodemus chevrieri and Niviventer fulvescens. Rodents from forests and shrublands had significantly higher Babesia infection rates. Genetic comparisons revealed that Babesia was most similar to the Kobe- and Otsu-type strains identified in Japan. A variety of rodent species might be involved in the enzootic maintenance and transmission of B. microti, supporting the need for further serological investigations in humans.
We study a special class of quasi-cyclic codes, obtained from a cyclic code over an extension field of the alphabet field by taking its image on a basis. When the basis is equal to its dual, the dual code admits the same construction. We give some examples of self-dual codes and LCD codes obtained in this way.
The effects of boron and zirconium contents from 0 to 0.049 wt% on the casting fluidity, as-cast microstructure and mechanical properties of IN718C superalloy are systematically investigated. The results show that as the B or Zr content increases, the fluidity firstly increases and then decreases. The optimum fluidity is obtained at the pouring temperature of 1470 °C when the content of B is 0.0059 wt% or Zr is 0.042 wt%, respectively. The addition of Zr can lead to the formation of blocky laves phase, but B has no influence on microstructure morphology. Furthermore, the addition of B or Zr can effectively improve the tensile and stress life properties as well as casting fluidity of IN718C superalloy. As compared with IN718C master alloys, the tensile strength can increase 6.2–8.6% and stress life can be improved by 1.3 times when B content is 0.0059 wt%. In addition, when the alloy contains 0.042 wt% Zr, the tensile strength can increase 5.6–7% and stress life can increase 1.076 times than that of the master alloy.
Building on the growing literature on interfirm links and limited attention, we find evidence of return predictability across alliance partners. A long–short portfolio sorted on lagged returns of strategic alliance partners provides a return of 89 basis points per month that is robust to a number of specifications. Investor inattention and limits to arbitrage may be the source of the underreaction of a firm’s returns to that of its partners.
We investigate theoretically the field-free orientation of CO molecules induced by a single-cycle THz laser pulse train. It is shown that the molecular orientation can be obviously enhanced by applying the pulse train. The laser intensity and pulse number have some effects on the molecular orientation. The high degree of field-free molecular orientation |⟨cosθ⟩|max=0.9246 is obtained at temperature T=0 K. The variations of the maximum orientation degree with the experimentally available pulse number and peak intensity are given. Temperature T has a considerable influence on the field-free molecular orientation. The maximal field-free molecular orientation at T=0, 10, 20 and 30 K for N=14 and E0=1.8 MV/cm are |⟨cosθ⟩|max=0.9188, 0.7338, 0.6055 and 0.5154 in order, and the corresponding effective duration times of molecular orientation are Δt=0.759, 0.432, 0.297 and 0.117 ps.
This investigation addresses the dynamics of annular viscoelastic films flowing down a flexible tube. The fluid viscoelasticity is assumed to be weak in order to obtain approximate explicit expressions for the stresses. Based on Shkadov’s integral boundary layer method (Fluid Dyn., vol. 2(1), 1967, pp. 29–34), a set of nonlinear evolution equations is derived that is valid for flows with moderate Reynolds numbers. The linear stability property of the system is examined by using normal-mode analysis, which is verified by comparing the results with those resulting from the linearization of the full Navier–Stokes equations. The results indicate that the fluid viscoelasticity plays an unstable role in the stability of the annular film flow. The tube flexibility, which includes wall damping and wall tension, plays a dual role. A bifurcation analysis is performed, and the families of steady travelling waves are catalogued. It is found that the stiffness of the tube tends to stimulate the interfacial capillary ripples. The fluid viscoelasticity acts to strengthen the dispersion of the interfacial waves but weakens the interfacial capillary ripples. The spatio-temporal evolutions of the system are also solved numerically. When the tube radius is small enough, tube closure can be observed due to the Plateau–Rayleigh instability. The fluid viscoelasticity acts to promote tube closure while the tube radius is relatively small. However, it plays a role in postponing the closure of the tube with a large radius.
Here we report on the photocurrent response of two-dimensional (2D) heterostructures of sputtered MoS2 on boron nitride (BN) deposited on (001)-oriented Si substrates. The steady state photocurrent (Iph) measurements used a continuous laser of λ = 658 nm (E = 1.88 eV) over a broad range of laser intensities, P (∼1 μW < P < 10 μW), and indicate that Iph obtained from MoS2 layers with the 80 nm BN under layer was ∼4 times higher than that obtained from MoS2 layers with the 30 nm BN under layer. We also found super linear dependence of Iph on P (Iph ∝ Pγ, with γ > 1) in both the samples. The responsivities obtained over the range of laser intensity studied were in the order of mA/W (∼12 and ∼2.7 mA/W with 80 nm BN and 30 nm BN under layers, respectively). These investigations provide crucial insight into the optical activity of MoS2 on BN, which could be useful for developing a variety of optoelectronic applications with MoS2 or other 2D transition metal dichalcogenide heterostructures.