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Inkjet printing, originally invented for text and pattern printing, is now central to many industrial applications, such as printed electronics, flexible electronics, 3-D printing of mechanical and even biological devices. However, constrained by the droplets’ ejection mechanism, the accuracy of traditional inkjet printing is limited by the size of its orifice, and it is difficult to achieve a volume of droplets at the femtolitre scale, which hinders its further application in the above fields. To this end, we propose the confined interface vibration inkjet printing (CIVIJP) technique, which is capable of printing patterns in a liquid environment with droplet size much smaller than the orifice from which they are dispensed. Here, further systematic study of the mechanism of printing in a liquid environment was carried out with the assistance of a high-speed imaging technique. It is found for the first time that a single pulse stimulation applied on the piezo-ceramic of the inkjet nozzle can trigger damping oscillations of the oil/water interface confined by the orifice, which can last more than 500 $\mathrm {\mu }$s. By adjusting the intensity of single pulse stimulation, the size and quantity of the dispensed droplets can be controlled in a wide range, which is obviously different from traditional droplet ejection in a gaseous environment. This work reveals the underlying physics between the pulse stimulation and the interface behaviours, as well as the physics between the interface behaviours and the size and number of dispensed droplets, enriching the fundamental theory of the inkjet printing in liquid phase.
To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.
Design:
In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage–response relationship between serum folate and the risk of GDM.
Setting:
A sigle, urban hospital in Shanghai, China.
Participants:
A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.
Results:
Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs)
Conclusions:
The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.
In this study, we report the first complete mitochondrial genome of the tapeworm Nippotaenia mogurndae in the order Nippotaeniidea Yamaguti, 1939. This mitogenome, which is 14,307 base pairs (bp) long with an A + T content of 72.2%, consists of 12 protein-coding genes, 22 transfer RNA (tRNA) genes, two rRNA genes, and two non-coding regions. Most tRNAs have a conventional cloverleaf structure, but trnS1 and trnR lack dihydrouridine arms of tRNA. The two largest non-coding regions, NCR1 (220 bp) and NCR2 (817 bp), are located between trnY and trnS2 and between nad5 and trnG, respectively. Phylogenetic analyses of mitogenomic data indicate that N. mogurndae is closely related to tapeworms in the order Cyclophyllidea.
This study aimed to evaluate the efficacy and safety of high-frequency oscillation ventilation combined with intermittent mandatory ventilation in infants with acute respiratory distress syndrome after congenital heart surgery.
Methods:
We retrospectively analysed the clinical data of 32 infants who were ventilated due to acute respiratory distress syndrome after congenital heart surgery between January, 2020 and January, 2022. We adopted high-frequency oscillation ventilation combined with intermittent mandatory ventilation as the rescue ventilation mode for infants who were failing conventional mechanical ventilation.
Results:
After rescue high-frequency oscillation ventilation combined with intermittent mandatory ventilation, the dynamic compliance (Cdyn), PaO2 and PaO2/FiO2 ratio of the infants improved compared with conventional mechanical ventilation (p < 0.05). Moreover, high-frequency oscillation ventilation combined with intermittent mandatory ventilation resulted in a significant decrease in arterial-alveolar oxygen difference (AaDO2), FiO2, and oxygenation index (p < 0.05). No significant effect on haemodynamic parameters was observed. Moreover, no serious complications occurred in the two groups.
Conclusion:
Rescue high-frequency oscillation ventilation combined with intermittent mandatory ventilation significantly improved oxygenation in infants who failed conventional mechanical ventilation for acute respiratory distress syndrome after congenital heart surgery. Thus, this strategy is considered safe and feasible. However, further studies must be conducted to confirm the efficacy and safety of high-frequency oscillation ventilation combined with intermittent mandatory ventilation as a rescue perioperative respiratory support strategy for CHD.
Polarization diversity technology is an effective method to improve the detection performance of passive radar systems, but the related papers mainly conduct research on the polarization diversity in interference suppression, and there are few studies focusing on the polarization characteristics of the target itself. The work in this paper is divided into two parts. The first part is going to investigate the potential benefits of signal fusion in target polarization-scattering characteristic. The analysis results show that the cross-polarized component of the target scattered echo is not always weaker than the co-polarized component, and the polarization amplitude ratio value is mostly concentrated near 1. This indicates that polarization signal fusion will likely improve target detection performance. The other part introduces a polarization signal fusion method based on the non-coherent integration (P-NCI), but this method is susceptible to the influence of the difference in the signal-to-noise ratio (SNR) of the signal of each polarization channel, resulting in a reduction in the SNR of the fusion signal. The polarization signal fusion method based on adaptive weighting (AW-PSF) can effectively improve the robustness of signal fusion. The experimental results show that AW-PSF has better detection performance compared with single-polarization channel and P-NCI.
In this paper, a metasurface (MS)-based multi-functional electromagnetic (EM) structure is proposed to realize its two different applications, namely absorption and radiation. The proposed structure is based on periodic arrays of disk-shaped metallic patches and split rings with four embedded lumped resistors. The metallic vias are inserted from top to bottom to connect the disk-shaped patches with a feeding network designed on the bottom layer where two p-i-n switches are embedded in the feeding network to alter the different functions of the proposed structure. For free space incident plan wave, the designed structure works as an absorber when the p-i-n switches are switched OFF. The absorber operates over a frequency band from 6.2 GHz to 8.2 GHz and unchanged over an incident angle from 0° to 30° for both TE and TM polarized incident waves. The same structure also works as a low scattering and high gain radiator when the p-i-n switches are turned ON and radiate within absorbing frequency band, i.e. from 7.5 to 8.0 GHz. The designed structure is fabricated and experimentally verified for EM absorption and radiation applications.
PU- and P*U*-equivalent parallel mechanisms (PMs) are critical families of PMs with one translational and two rotational (1T2R) degree of freedoms and have always been a research hotspot among lower mobility PMs. However, researches on these two families of PMs remain to be inadequate, and existing types are few and uncomprehensive. In this study, first, general wrench systems of PU-equivalent are derived based on virtual-chain approach and screw theory, revealing its constraint characteristics under general configuration. Cause of one parasitic motion is put forward and general wrench systems of P*U*-equivalent PMs with one parasitic motion are obtained. In addition, constraint analysis has been carried out to figure out constraint characteristics of P*U*-equivalent PMs with three parasitic motions. Second, branch chains are divided by generating constraints, and their structures are synthesized based on the presented rules. Then, the process for type synthesis of PU-equivalent PMs and P*U*-equivalent PMs and a series of novel 1T2R PMs are attained based on this. Finally, a novel PU-equivalent PM, 2PRU-PRUPc, and a novel P*U*-equivalent PM with one parasitic motion, 2PRU-PUU PM, are analyzed, demonstrating the effectiveness of the proposed type synthesis method.
As an attractive collector medium for hypervelocity particles, combined with outstanding physical properties and suitable compositional characteristics, SiO2 aerogel has been deployed on outer space missions and laser shock-loaded collection experiments. In this paper, impact experiments were conducted to understand the penetration process of irregular grains, irregular Al2O3 grains with two different sizes and speeds (~110 μm@7 km/s, ~251 μm@2.3 km/s) at various density silica aerogels. By classifying the shapes of projectile residues and tracks, the morphology of tracks was analyzed. It was observed that there were several kinds of typical tracks in the penetration of irregular grains, accompanied by residues with the shapes of near-sphere, polyhedron, streamlined body wedge, and rotator. The rotational behavior was demonstrated by the final status of one flake projectile as direct evidence. In addition, there was no obvious relationship between the track length and experimental parameters, which may be caused by the uncertain interaction between aerogels and irregular particles. In addition, it confirmed the existence of fragmentation, melting situation by observing the shape of the impact entrance hole. At the same time, optical coherence tomography was used to observe the detail of tracks clearly, which provided a method to characterize the tracks nondestructively.
Redroot pigweed (Amaranthus retroflexus L.) is a troublesome dicot weed species widely distributed across China. A population of A. retroflexus that survived the recommended label rate of thifensulfuron-methyl was collected from the main soybean [Glycine max (L.) Merr.] production area in China. Whole-plant dose–response assays indicated that the resistant (R) population was highly resistant (61.80-fold) to thifensulfuron-methyl compared with the susceptible (S1 and S2) populations. In vitro acetolactate synthase (ALS) activity experiments showed that the thifensulfuron-methyl I50 value for the R population was 40.17 times higher than that for the S1 population. A preliminary malathion treatment study indicated that the R population might have cytochrome P450–mediated metabolic resistance. The R population exhibited a high level of cross-resistance to representative ALS herbicides (imazethapyr, flumetsulam, and bispyribac-sodium) and multiple resistance to the commonly used protoporphyrinogen oxidase (PPO)-inhibiting herbicides lactofen and fomesafen. Two common mutations, Trp-574-Leu in ALS and Arg-128-Gly in PPO2, were identified within the R population. This study identified possible enhanced metabolism of thifensulfuron-methyl coexisting with target-site mutations in both ALS and PPO2 in a multiple-resistant A. retroflexus population.
The present study was undertaken to investigate the antiparasitic activity of extracellular products of Streptomyces albus. Bioactivity-guided isolation of chloroform extracts affording a compound showing potent activity. The structure of the compound was elucidated as salinomycin (SAL) by EI-MS, 1H NMR and 13C NMR. In vitro test showed that SAL has potent anti-parasitic efficacy against theronts of Ichthyophthirius multifiliis with 10 min, 1, 2, 3 and 4 h (effective concentration) EC50 (95% confidence intervals) of 2.12 (2.22–2.02), 1.93 (1.98–1.88), 1.42 (1.47–1.37), 1.35 (1.41–1.31) and 1.11 (1.21–1.01) mg L−1. In vitro antiparasitic assays revealed that SAL could be 100% effective against I. multifiliis encysted tomonts at a concentration of 8.0 mg L−1. In vivo test demonstrated that the number of I. multifiliis trophonts on Erythroculter ilishaeformis treated with SAL was markedly lower than that of control group at 10 days after exposed to theronts (P < 0.05). In the control group, 80% mortality was observed owing to heavy I. multifiliis infection at 10 days. On the other hand, only 30.0% mortality was recorded in the group treated with 8.0 mg L−1 SAL. The median lethal dose (LD50) of SAL for E. ilishaeformis was 32.9 mg L−1.
Several studies have suggested that higher carotenoid levels may be beneficial for atherosclerosis patients, but few studies have examined this relationship in the Chinese population. This cross-sectional study examined the association between the levels of carotenoids in diet and serum and carotid intima–media thickness (IMT) in Chinese adults aged 50–75 years in Guangzhou, China. Dietary intake was assessed using a FFQ. HPLC was used to assay the serum concentrations of α-carotene, β-carotene, lutein+zeaxanthin, β-cryptoxanthin and lycopene. The IMT at the common carotid artery (CCA) and bifurcation of the carotid artery was measured by B-mode ultrasound. A total of 3707 and 2947 participants were included in the analyses of dietary and serum carotenoids. After adjustment for demographic, socio-economic and lifestyle factors, all the serum carotenoids levels except lycopene were found to be inversely associated with the IMT at the CCA and bifurcation (Ptrend<0·001 to 0·013) in both men and women. The absolute mean differences in the IMT between the subjects in the extreme quartiles of serum carotenoid levels were 0·034 mm (α-carotene), 0·037 mm (β-carotene), 0·032 mm (lutein+zeaxanthin), 0·030 mm (β-cryptoxanthin), 0·015 mm (lycopene) and 0·035 mm (total carotenoids) at the CCA; the corresponding values were 0·025, 0·053 0·043, 0·050, 0·011 and 0·042 mm at the bifurcation. The favourable associations were also observed between dietary carotenoids (except lycopene) and the CCA IMT. In conclusion, elevated carotenoid levels in diet and serum are associated with lower carotid IMT values (particular at the CCA) in Chinese adults.
The prevalence of CHD has been well described worldwide except in Tibet. This study aimed to illustrate the prevalence and composition of CHD in Tibetan children according to altitude.
Methods and results
In the first part, we prospectively recruited 7088 unselected Tibetan children (4–17 years) from south-west Tibet. The total prevalence of CHD increased from 4.6/1000 below 4200 m to 13.4/1000 above 4700 m, with a female-to-male ratio of 1.3:3.1. The total prevalence and female prevalence of patent ductus arteriosus increased more than 10-fold. Females living above 4700 m had exceptionally high prevalence of patent ductus arteriosus (14.9/1000). The prevalence of atrial septal defect was comparable among different altitudes (3.3–3.8/1000). The prevalence of ventricular septal defect was 1.3/1000 below 4700 m, and no cases were found above this altitude. In the second part, we retrospectively reviewed the clinical data of 383 CHD children in Tibet and 73 children at lower altitudes. The percentage of isolated ventricular septal defect decreased from 54.8 to 3.1%, and the percentage of isolated patent ductus arteriosus increased from 8.2 to 68.4% with elevation. Children living below 4200 m (10.4–13.7%) had a larger proportion of complex CHD than those above this altitude (2.0–3.1%). Of the 20 Tibetan children with complex CHD, 14 (70.0%) lived below 4200 m.
Conclusions
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
We present a reconstructed lithologic column compiled from a series of lacustrine outcrops along a tributary of the Nyang River, a major tributary of the Yarlung-Tsangpo in southeast Tibet. The deposits were preserved between terraces at altitudes of 2950–3100 m asl. The stratigraphic record features at least two sets of coarsening-upward sequences depicting episodic aggradation and progradation of a glacially dammed lake related delta. Recognized facies changes illustrate the evolution cycles of depositional environments from pro-delta, delta front, to delta plain. Radiocarbon and optically stimulated luminescence dates reveal an aging-downward trend in stratigraphic order and provide an approximate timeline for the formation of glacially dammed lakes in late Pleistocene. This result reflects that the Zelunglung Glacier had progressively advanced to block the Yarlung-Tsangpo river and the dam materials had stepwise stacked up to an altitude of 3095 m asl during Marine Oxygen Isotope Stages 4 to 2.
In this paper, field effect transistors (FET) based on different kinds of non-graphene materials are introduced, which are MoS2, WSe2 and black phosphorus (BP). Those devices have their unique features in fabrication process compared with conventional FETs. Among them, MoS2 FET shows better electrical characteristics by applying a SiO2 protective layer; WSe2 FET is fabricated based on a new low pressure chemical vapor deposition (LPCVD) method; BP FET acquires high on/off ratio and high hole mobility by using a simple dry transfer method. Those novel non-graphene materials inspire new design and fabrication process of basic logic device.
To investigate natural enemies of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in northeastern China, we conducted field surveys of ash (Fraxinus Linnaeus (Oleaceae)) trees in semi-natural forests and plantations at variable EAB densities from 2008 to 2013. Our surveys revealed a complex of natural enemies including eight hymenopteran parasitoids and two apparently parasitic Coleoptera, woodpeckers, and several undetermined mortality factors. Parasitoid complex abundance and its contribution to EAB mortality varied with the time of year, type of ash stands, and geographic regions. The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) and the larval parasitoid Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) were frequently observed in Jilin, Liaoning, and Heilongjiang provinces and in Beijing, but not in Tianjin. Spathius agrili Yang (Hymenoptera: Braconidae), however, was more prevalent near Beijing and further south in Tianjin. Larvae of two species of apparently parasitic beetle, Tenerus Laporte (Coleoptera: Cleridae) species and Xenoglena quadrisignata Mannerheim (Coleoptera: Trogossitidae), were also recovered attacking overwintering EAB in Liaoning Province, with Tenerus species being a dominant mortality agent (~13%). Our findings support the need to consider the geographic origin of insect natural enemies for EAB biocontrol, as well as an expanded foreign exploration for EAB natural enemies throughout its native range in Asia.