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To establish optimal gestational weight gain (GWG) in Chinese pregnant women by Chinese-specific BMI categories and compare the new recommendations with the Institute of Medicine (IOM) 2009 guidelines.
Design:
Multicentre, prospective cohort study. Unconditional logistic regression analysis was used to evaluate the OR, 95 % CI and the predicted probabilities of adverse pregnancy outcomes. The optimal GWG range was defined as the range that did not exceed a 1 % increase from the lowest predicted probability in each pre-pregnancy BMI group.
Setting:
From nine cities in mainland China.
Participants:
A total of 3731 women with singleton pregnancy were recruited from April 2013 to December 2014.
Results:
The optimal GWG (ranges) by Chinese-specific BMI was 15·0 (12·8–17·1), 14·2 (12·1–16·4) and 12·6 (10·4–14·9) kg for underweight, normal weight and overweight pregnant women, respectively. Inappropriate GWG was associated with several adverse pregnancy outcomes. Compared with women gaining weight within our proposed recommendations, women with excessive GWG had higher risk for macrosomia, large for gestational age and caesarean section, whereas those with inadequate GWG had higher risk for low birth weight, small for gestational age and preterm delivery. The comparison between our proposed recommendations and IOM 2009 guidelines showed that our recommendations were comparable with the IOM 2009 guidelines and could well predict the risk of several adverse pregnancy outcomes.
Conclusions:
Inappropriate GWG was associated with higher risk of several adverse pregnancy outcomes. Optimal GWG recommendations proposed in the present study could be applied to Chinese pregnant women.
Since December 2019, China has experienced a widespread outbreak of COVID-19. However, at the early stage of outbreak, investigations revealed a variety of patterns resulting in the transmission of COVID-19. Thus, it is essential to understand the transmission types and the potential for sustained human-to-human transmission. Moreover, the information regarding the characteristics of transmission helps in coordinating the current screening programme, and controlling and containing measures, and also, helps in deciding the appropriate quarantine duration. Thus, this investigation reports an outbreak of COVID-19 in a family residing in Wenzhou, Zhejiang, China during the month of January−February 2020.
We incorporate deep learning (DL) into tiled aperture coherent beam combining (CBC) systems for the first time, to the best of our knowledge. By using a well-trained convolutional neural network DL model, which has been constructed at a non-focal-plane to avoid the data collision problem, the relative phase of each beamlet could be accurately estimated, and then the phase error in the CBC system could be compensated directly by a servo phase control system. The feasibility and extensibility of the phase control method have been demonstrated by simulating the coherent combining of different hexagonal arrays. This DL-based phase control method offers a new way of eliminating dynamic phase noise in tiled aperture CBC systems, and it could provide a valuable reference on alleviating the long-standing problem that the phase control bandwidth decreases as the number of array elements increases.
Maternal supraphysiological estradiol (E2) environment during pregnancy leads to adverse perinatal outcomes. However, the influence of oocyte exposure to high E2 levels on perinatal outcomes remains unknown. Thus, a retrospective cohort study was conducted to explore the effect of high E2 level induced by controlled ovarian stimulation (COH) on further outcomes after frozen embryo transfer (FET). The study included all FET cycles (n = 10,581) between 2014 and 2017. All cycles were categorized into three groups according to the E2 level on the day of the human Chorionic Gonadotropin trigger. Odds ratios (ORs) and their confidence intervals (CIs) were calculated to evaluate the association between E2 level during COH and pregnancy outcomes and subsequent neonatal outcomes. From our findings, higher E2 level was associated with lower percentage of chemical pregnancy, clinical pregnancy, ongoing pregnancy, and live birth as well as increased frequency of early miscarriage. Preterm births were more common among singletons in women with higher E2 level during COH (aOR1 = 1.93, 95% CI: 1.22–3.06; aOR2 = 2.05, 95% CI: 1.33–3.06). Incidence of small for gestational age (SGA) was more common in both singletons (aOR1 = 2.01, 95% CI: 1.30–3.11; aOR2 = 2.51, 95% CI: 1.69–3.74) and multiples (aOR1 = 1.58, 95% CI: 1.03–2.45; aOR2 = 1.99, 95% CI: 1.05–3.84) among women with relatively higher E2 level. No association was found between high E2 level during COH and the percentage of macrosomia or large for gestational age. In summary, oocyte exposure to high E2 level during COH should be brought to our attention, since the pregnancy rate decreasing and the risk of preterm birth and SGA increasing following FET.
Image stitching is important for the perception and manipulation of undersea robots. In spite of a well-developed technique, it is still challenging for undersea images because of their inevitable appearance ambiguity caused by the limited light in the undersea environment, and local disturbance caused by moving objects, ocean current, etc. To get a clean and stable background panorama in the undersea environment, this paper proposes an undersea image-stitching method by introducing graph-based registration and blending procedures. Specifically, in the registration procedure, matching the features in each undersea image pair is formulated and solved by graph matching, to incorporate the structural information between features. In the blending procedure, an energy function on the indirect graph Markov random field is proposed, which takes both image consistency and neighboring consistency into consideration. Coincidentally, both graph matching and energy minimization can be mathematically formulated by integer quadratic programming problems with different constraints; the recently proposed graduated nonconvexity and concavity procedure is used to optimize both problems. Experiments on both synthetic images and real-world undersea images witness the effectiveness of the proposed method.
More than 200 molecular clouds were newly found distributed beyond the Outer arm in the extreme outer Galaxy (EOG) region by MWISP. Those MCs roughly following the HI′s distribution well delineate the outermost spiral structure (the Outer Scutum-Centaurus arm) and warp of our Galaxy. Besides, those MCs show different σv-Radius relation and exhibit higher value of αvir than MCs in the inner Galaxy.
Alligatorweed is well known for its potassium (K+)-accumulating
capabilities and its strong resistance to undesired growth conditions. The
results of this study revealed properties of K+ accumulation and
its contribution to drought stress in alligatorweed. In addition, we
attempted to characterize the molecular mechanisms of K+
accumulation in this plant. Alligatorweed plants showed a consistent
increase in biomass in response to external K+ concentrations,
ranging from micromolar levels up to 50 mmol L−1; K+
was also accumulated accordingly in the plants. The stem was the most
K+-accumulating organ, accumulating up to 13% of the
K+. Moreover, this K+ superaccumulation caused
improved resistance to drought stress. The apparent K+ uptake by
the roots showed a typical high-affinity property, and the Michaelis
constant increased at higher rates of plant K+ in the starting
materials. Furthermore, three putative, K+-uptake transporter
complementary DNAs (cDNAs) were isolated from alligatorweed (ApKUP1,
ApKUP2, and ApKUP3, respectively) using
degenerated primers and rapid amplification of cDNA end techniques. The
expression of ApKUP1 and ApKUP3 was
predominately localized to the leaves, whereas ApKUP2 was
expressed throughout the entire plant. The expression of
ApKUP1 and ApKUP3 was stimulated in the
stems and roots when K+ was depleted from the external medium.
Moreover, ApKUP3 expression was enhanced in the stem in
response to abscisic acid treatment and drought stress. In conclusion, our
findings provide further insight into the mechanisms of K+
accumulation linked to K+ uptake in alligatorweed.
Isothermal homogenization heat treatments for a GCr15 bearing steel cast billet were performed at temperatures of 1000–1250 °C and holding times of 30–180 min. The grain size of austenite was measured with a metallographic microscope through the linear intercept method. Experimental results show that the grain size of austenite increases with the increase in heating temperature and holding time. The relationship between grain size and homogenization cycles was established. The homogeneity of the cast billet has an obvious effect on the austenite grain size distributions. Small and large grains were observed in the high- and low-concentration regions, respectively. The log-normal function can describe the grain size distributions more accurately than other functions after heating at low temperatures for short times. However, the Weibull function fits the grain size data well when the heating temperatures and holding times are improved.
Disaster can strike people in any community at any time anywhere in the world. Disasters occur with high frequency, take on multiple forms, and exert wide influence, typically causing property damage, injuries, and death. As the world’s largest developing country, China incurs great costs when a disaster hits. After the Wenchuan earthquake in 2008, the Chinese government focused its attention on the construction of an emergency response system, the creation of disaster prevention and mitigation systems, and the development of a disaster medicine program. Here, we describe the current status of disaster medicine in China, focusing on the following four aspects: the Emergency Management System, Education & Training, Rescue Practices, and Research. We also discuss the future of disaster medicine in China. (Disaster Med Public Health Preparedness. 2018;12:157–165)
The present study aimed to explore the associations between food away-from-home (FAFH) consumption and body weight outcomes among Chinese adults.
Design
FAFH was defined as food prepared at restaurants and the percentage of energy from FAFH was calculated. Measured BMI and waist circumference (WC) were used as body weight outcomes. Quantile regression models for BMI and WC were performed separately by gender.
Setting
Information on demographic, socio-economic, diet and health parameters at individual, household and community levels was collected in twelve provinces of China.
Subjects
A cross-sectional sample of 7738 non-pregnant individuals aged 18–60 years from the China Health and Nutrition Survey 2011 was analysed.
Results
For males, quantile regression models showed that percentage of energy from FAFH was associated with an increase in BMI of 0·01, 0·01, 0·01, 0·02, 0·02 and 0·03 kg/m2 at the 5th, 25th, 50th, 75th, 90th and 95th quantile, and an increase in WC of 0·04, 0·06, 0·06, 0·04, 0·06, 0·05 and 0·07 cm at the 5th, 10th, 25th, 50th, 75th, 90th and 95th quantile. For females, percentage of energy from FAFH was associated with 0·01, 0·01, 0·01 and 0·02 kg/m2 increase in BMI at the 10th, 25th, 90th and 95th quantile, and with 0·05, 0·04, 0·03 and 0·03 cm increase in WC at the 5th, 10th, 25th and 75th quantile.
Conclusions
Our findings suggest that FAFH consumption is relatively more important for BMI and WC among males rather than females in China. Public health initiatives are needed to encourage Chinese adults to make healthy food choices when eating out.
A congruent melting compound LiNaV2O6 has been synthesized by high-temperature solution reaction and it has been grown with sizes up to 11 × 6 × 2 mm3 by the top-seeded growth method for the first time. LiNaV2O6 crystallizes in the monoclinic system with space group C2/c, with a = 10.184(2) Å, b = 9.067(2) Å, c = 5.8324(11) Å, β = 108.965(14)°. UV–Vis–NIR diffuse reflectance spectrum of LiNaV2O6 shows that it has a wide transmittance range from 385 to 2500 nm. The ab initio calculations show that the birefringence of LiNaV2O6 is 0.136 at 589.3 nm. Therefore, LiNaV2O6 may be a new birefringent material. Based on the analysis of the relationship between crystal structure and linear optical properties, it is found that the large birefringence is attributed to the particular arrangement of V–O anionic groups.
Tesla transformers are widely used in short pulse, repetition pulsed power generators. In this paper, a high repetitive rate intense electron beam accelerator (IEBA) based on high coupling (~1) Tesla transformer, which consists of a primary charging system, coaxial pulse forming line (PFL) charged by Tesla transformer and gas spark switch is described, especially stressed on the high coupling Tesla transformer. By introducing magnetic core to enhance the coupling factor between the primary and secondary windings, the transformer is capable of producing high voltage pulse up to 1.4 MV in approximately 45 µs. A coaxial pulse forming line is closely attached to the transformer that the outer and inner magnetic cores are parts of the PFL's outer and inner conductors respectively. In addition, the parameters of the Tesla transformer and PFL are calculated, including the dimension of the PFL and Tesla transformer. Some experiment results showed that the IEBA is capable of producing electron beams of 300–700 kV/7–13 kA at repetitive rate 100 Hz, with the pulse width 35 ns. The maximal energy efficiency of the Tesla transformer is 83%.
Angiostrongylus cantonensis infection causes eosinophilic meningitis in humans. Baicalein is a flavonoid originally isolated from the roots of Scutellaria baicalensis Georgi. In this study we evaluated the efficacy of the combination of albendazole and baicalein for treating eosinophilic meningitis in BALB/c mice. Therapeutic efficacy included the survival time, body weight, neurological function, leucocyte and eosinophil counts, eotaxin concentration, matrix metalloproteinase-9 (MMP-9) activity, larval recovery and histopathological examination. The results showed that the combination of albendazole and baicalein was more effective than either drug administered singly. Combination therapy increased the survival time, decreased body weight loss, neurological dysfunction, leucocyte response, eotaxin concentration and MMP-9 activity. Our results suggest that the combination of albendazole and baicalein may exhibit synergistic beneficial effects in the treatment of eosinophilic meningitis induced by A. cantonensis.
To identify the disease-causing gene for a large multi-generational Chinese family affected by familial hypertrophic cardiomyopathy (FHCM), genome-wide screening was carried out in a Chinese family with FHCM using micro-satellite markers, and linkage analysis was performed using the MLINK program. The disease locus was mapped to 1q32 in this family. Screening for a mutation in the cardiac troponin T (cTnT) gene was performed by a PCR and sequencing was done with an ABI Prism 3700 sequencer. A novel C→G transition located in the ninth exon of the cTnT gene, leading to a predicted amino acid residue change from Ile to Met at codon 90, was identified in all individuals with hypertrophic cardiomyopathy (HCM). The results presented here strongly suggest that Ile90Met, a novel mutation in the cTnT gene, is causative agent of HCM in this family.
To evaluate echocardiographically the function and morphology of the right heart subsequent to transcatheter closure of atrial septal defects.
Methods
We performed echocardiographic studies in 73 patients undergoing transcatheter closure of atrial septal defects 1 day prior to closure, and then 3 days and 3 months after closure. We calculated the antero-posterior diameter of the right ventricle, the transverse diameter and length of the right atrium, the pulmonary arterial pressure, and the velocities of systolic movement and early and late diastolic movement of the basal parietal walls of the right ventricle.
Results
The atrial septal defects varied in size between 8 and 33 millimetres, and were closed using occluders measuring from 10 to 40 millimetres. At 3 days after closure, the antero-posterior diameter of the right ventricle, the transverse diameter and length of the right atrium, the pulmonary arterial pressure, and the velocities of mural motion were all significantly decreased. After 3 months, the size of the right heart had more or less normalized.
Conclusions
Transcatheter closure of atrial septal defects produces marked improvement in the function and geometry of the chambers of the right heart, reducing pulmonary arterial pressure as well as abolishing the interatrial shunt.
HbUEP, an ubiquitin extension protein gene from latex of the rubber tree (Hevea brasiliensis) was cloned and sequenced using a differentially ethphon-induced expressed cDNA subtraction library. The cDNA had 771 bp nucleotides, comprising a 226 bp 3′ untranslated region (UTR), 77 bp 5′UTR and a 468 bp open reading frame encoding a 156 amino acid peptide. Southern blotting analysis showed that this gene was a low copy number gene in the H. brasiliensis genome. Within 24 h after application of ethphon, the gene was expressed weakly in both control and latex sampled at 6 h, and strongly in latex sampled at 12 h, showing that this gene expression could be regulated by ethphon. Ethphon could increase the latex yield in H. brasiliensis. It is suggested that the HbUEP gene may be involved in the regulation of ethphon-induced high latex yield in H. brasiliensis.
The isozymes of 10 enzymes connected with energy metabolism in Tegillarca granosa were analysed by vertical polyacrylamide gel electrophoresis. Esterase and α-amylase are enzymes related to energy intake, their activities were high in the digestive gland. Malate dehydrogenase, malic enzyme, isocitrate dehydrogenase, succinate dehydrogenase, alcohol dehydrogenase, lactate dehydrogenase, 6-phosphogluconate dehydrogenase (G-6-PDH) and adenosine triphosphatase (ATPase) are enzymes related to energy metabolism. The main energy supply of T. granosa comes from aerobic respiration; anaerobic metabolism and the pentose phosphate pathway take an auxiliary role in energy metabolism. The high activity of G-6-PDH in T. granosa might mean a considerable proportion of carbohydrates metabolized through this pathway. This reaction could provide abundant NADP for metabolism in T. granosa. Compared with other shellfish, T. granosa had lower activity of ATPase, which might have some relationship with the amnicolous life and low motility of this animal.
Piezoelectric properties k33 and d33 of 0.67 Pb(Mg1/3Nb2/3)O3–0.33 PbTiO3 single crystals grown by a modified Bridgman method were measured in the temperature range of 20–150 °C. Recoverability of the properties after the samples were heated to 110 °C, above the ferroelectric–ferroelectric (F–F) phase transition temperature of the composition, was found. From 20 to approximately 80 °C, k33 increases slightly, while d33 is almost doubled. Between approximately 90 and 100 °C, k33 decreases sharply to roughly a level of PZT-5 ceramics and d33 decreases to about 700 pC/N. They increase again with further increase of temperature; at 140 °C they attain 0.74 and approximately 1300 pC/N, respectively, and then decrease quickly and approach zero at about 150 °C. When heating to 110 °C followed by cooling to room temperature, the property decay is small. After more than one dozen heating–cooling cycles, k33 and d33 tend to be stable at 0.89 and approximately 1220 pC/N, respectively. The results might be helpful for device design and applications of PMN–PT single crystals.
Let K be a compact subset of ℝn,
0[les ]s[les ]n. Let Ps0,
[Pscr ]s denote s-dimensional packing premeasure and
measure, respectively. We discuss in this paper the relation between
Ps0 and [Pscr ]s. We prove:
if Ps0(K)<∞, then
[Pscr ]s(K) = Ps0(K);
and if Ps0(K) = ∞,
then for any ε>0, there exists a compact subset F of K such
that [Pscr ]s(F)
= Ps0(F) and
[Pscr ]s(F)[ges ]
[Pscr ]s(K)−ε.