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The Ginzburg–Landau equation (GLE) can phenomenologically model several key features of non-equilibrium systems including those in fluid mechanics. Its validity in real flows, however, remains questionable. Here, we show that the linear GLE can be formulated such that it has the same Wentzel–Kramers–Brillouin (WKB) approximation as for the linear global stability problem in open shear flows. We use the GLE to model the linear global modes of three different wakes and find that it can accurately capture the linear growth rate and frequency to first order in the WKB approximation. Furthermore, we find that it can also provide the shapes of the direct and adjoint eigenvectors and the regions of maximal structural sensitivity. The proposed model requires only the basic flow as input, but gives robust predictions and is computationally inexpensive. As well as opening up new possibilities for GLE-based control strategies, the proposed model makes accurate stability calculations possible, even for some computationally intractable open shear flows.
The ablation and acceleration of diamond-like high-density carbon foils irradiated by thermal X-ray radiations are investigated with radiation hydrodynamics simulations. The time-dependent front of the ablation wave is given numerically for radiation temperatures in the range of 100–300 eV. The mass ablation rates and ablation pressures can be derived or implied from the coordinates of ablation fronts, which agree well with reported experiment results of high-density carbon with radiation temperatures Trad in the range of 160–260 eV. It is also found that the
scaling law for ablation rates does not apply to Trad above 260 eV. The trajectories of targets and hydrodynamic efficiencies for different target thicknesses can be derived from the coordinates of ablation fronts using a rocket model and the results agree well with simulations. The peak hydrodynamic efficiencies of the acceleration process are investigated for different foil thicknesses and radiation temperatures. Higher radiation temperatures and target thicknesses result in higher hydrodynamic efficiencies. The simulation results are useful for the design of fusion capsules.
Nitrogen is an important element for the growth of flue-cured tobacco and is closely related to its yield and quality. In order to pursue higher economic benefits, excessive fertilizer is generally applied in flue-cured tobacco production, which is unfavourable for the sustainable development of flue-cured tobacco production and for the environment. In 2016 and 2017, experiments using different nitrogen fertilizer application rates in flue-cure tobacco were conducted in Yunnan province, and the changes in agronomic, economic and chemical indices as well as in residual soil nitrogen were compared. Linear and quadratic models were used to compare the response of tobacco to nitrogen fertilizer. With increasing nitrogen fertilizer rate, the proportions of superior to medium tobacco and the average price of flue-cured tobacco leaves initially increased and then decreased, while fresh weight, dry weight and the proportion of inferior tobacco showed the opposite trend. Total sugar and reducing sugar contents decreased with increasing nitrogen fertilizer rates, while total nitrogen and nicotine contents increased. Sensory evaluation scores had the highest value when 90 kg N/ha and 120 kg N/ha were applied. Soil nitrate contents increased as nitrogen fertilizer rate increased. The quadratic model was suitable for the response of cultivar K326 to nitrogen and 90 kg N/ha could meet the needs of cultivar K326.
Honeycomb phononic crystal can obtain wider band gaps in the low frequency based on local resonance theory. Its band structure can be adjustable if we change the height of the cores, which means different kinds of honeycomb phononic crystal can be selected on the basis of different damping demands. Meanwhile, the point defects and line defects affect the localized modes of sound waves and propagation characteristics, the dispersion relations and the displacement fields of the eigenmodes are calculated in the defected systems, as well as the propagation behaviors in the frequency ranges of the band structure, which are also discussed in detail. We constructed the model based on the periodic boundary condition and calculated the band structure according to Bloch theory, and also performed a series of simulation through the COMSOL software, showing that honeycomb has excellent features in reducing noise and vibration, which has a far-reaching influence in designing the new type of acoustic wave devices.
Polyglycolide (PGA) materials have been widely used in the medical field, but the degradation mechanism in the natural environment is still unclear. High-viscosity PGA was prepared by using twin-screw reaction extrusion polymerization. The mass and intrinsic viscosity of PGA samples, the pH of the solution surrounding the PGA samples in water, and the number of degradation products resulting from the degradation of the PGA samples were studied under different conditions and at different temperatures. PGA does not degrade at 70 °C in either dry air or in a vacuum. Infrared spectroscopy (FTIR) and differential spectroscopy revealed that the PGA samples in water at 70 °C for 40 days had a substantially reduced mass and substantially altered thermal behavior when compared with the control sample (undegraded PGA sample). The degradation of the PGA samples in humid conditions at 70 °C was similar to the degradation of the samples in water at 70 °C. The results of this study indicate that water and water vapor (moisture) in the natural environment are the main causes of PGA degradation, and higher temperatures accelerate the degradation process, which shortens the shelf life and life of PGA.
This research involves a compact wideband circularly-polarized antenna array, which consists of a sequential rotating phase feed network, 2 × 2 mushroom-type metamaterial (MTM) unit, and so on. Each antenna array unit contains a microstrip feedline, an L-shaped slot antenna, and so on. The MTM-based antennas were incorporated with a sequential-phase network of sequentially rotated series-parallel feed to achieve wideband operation. The operational bandwidth and the radiation model in the high-frequency area were improved through the adjustment of spacing between the L-shaped slots while maintaining the size and structure of the MTM. The proposed design had dimensions of 80 mm × 80 mm × 3.5 mm (~1.64 λ0 × 1.64 λ0 × 0.072 λ0 at 6.15 GHz), and it was simulated, fabricated, and tested.
Starch content is an important trait in barley. To evaluate the genetic diversity and identify molecular markers of starch content in barley, 40 cultivated barley genotypes collected from different regions, including genotypes whose starch content is at either the high or low end of the spectrum (15), were used in this study. All the genotypes were re-sequenced by the double-digest-restriction associated DNA sequencing method, and a total of 299,103 single-nucleotide polymorphism (SNP) markers were obtained. The genotypes were divided into four sub-populations based on FASTSTRUCTURE, principal component analysis and neighbour-joining tree analysis. All four sub-populations had a high linkage disequilibrium, especially group 3, whose members were recently bred for malting in the Jiangsu coastal area. The starch content of the barley lines was evaluated during three growing seasons (2014–2017), and the average values of starch content across the three growing seasons at the low and high ends were 51.5 and 55.0%, respectively. The starch content was affected by population structure, the barley in group 2 had a low starch content, while the barley in group 4 had a high starch content. Twenty-six SNP markers were identified as being significantly associated with starch content (P ⩽ 0.001) based on the average values across the three growing seasons using the mixed linear model method. These SNP markers were located on chromosomes 1H and 4H, and were considered loci of qSC1-1 and qSC4-1, respectively. The major identified QTLs for starch content are helpful for further research on carbohydrates and for barley breeding.
The storage root of alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.] growing in terrestrial habitats is an important metamorphic organ for its propagation, overwintering, and spread. However, the regulatory mechanism adventitious root expansion to form storage roots is still unclear. To reveal the changes accompanying the root-swelling process, we quantified sugar, soluble protein, and phytohormone content in adventitious and storage roots. Results demonstrated that sucrose, fructose, and soluble protein increased in storage roots, whereas abscisic acid (ABA), indoleacetic acid (IAA), brassinosteroid (BR), gibberellin, jasmonic acid, and cytokinin (trans-zeatin [tZ] and isopentenyladenine [iP] and the corresponding ribosides tZR and iPR). tZ-type (tZR and tZ) content decreased, suggesting the involvement of sugars and hormones in the formation of storage roots. To further reveal the molecular basis of A. philoxeroides’s ability to form storage roots and provide candidate genes for molecular function analyses, we assembled a de novo transcriptome of A. philoxeroides based on four sets of RNA-sequencing data. According to functional annotation and expression profiling, 42 unigenes involved in sucrose synthesis and hydrolysis were identified, in addition to 70, 58, and 78 unigenes in ABA, BR, and IAA signal transduction, respectively. The quantitative reverse transcriptase polymerase chain reaction analysis revealed 21 unigenes involved in sugar metabolism and hormone signal transduction were differentially expressed during the formation of storage roots. These results revealed metabolic changes during the formation of storage roots and provide candidate genes involved in sugar and phytohormone metabolism in A. philoxeroides.
Physicians' attitudes and adoption behavior toward the delivery of prenatal tests take vital significance for its influence on their professional practice and patient acceptance. This study aimed to identify how physicians have perceived the diffusion of non-invasive prenatal testing (NIPT) in China.
A cross-sectional study was conducted from July 2016 to October 2016 in Shanghai, and Fujian and Sichuan Provinces in China. Physicians working on prenatal screening completed a self-report questionnaire. Following Roger's diffusion of innovation model, multivariable logistic regressions were performed separately for the following key elements of the theory which influence diffusion: physician-perceived attributes of NIPT, communication channels, the nature of the social system, the extent of change agent (who introduces innovations into a society), promotion efforts, and physicians' benefits from adopting NIPT.
Most specialists had a positive attitude (53.2 percent) toward NIPT, whereas 58.9 percent of physicians had already adopted NIPT in their clinical practice. Physician adoption of NIPT was positively associated with the strength of HTA evidence (p = .03), perceived communication frequency with colleagues (p = .04), adoption by other physicians (p = .07), hospital competition (p = .06), hospital teaching status (p = .02), perceived for-profit genetic testing company's promotion (p < .001), and perceived clinical practice skill improvement (p = .02). However, the adoption behavior toward NIPT may be negatively associated with physician-perceived ethical concerns of NIPT (p = .06).
Obstetricians and gynecologists’ positive perceptions facilitate the adoption of NIPT. Combined with cost-effectiveness analysis of prenatal screening methods, health policy makers can promote the adoption of appropriate, cost-effective prenatal screening in pregnant women.
Beef cattle are often fed high-concentrate diet (HCD) to achieve high growth rate. However, HCD feeding is strongly associated with metabolic disorders. Mild acid treatment of grains in HCD with 1% hydrochloric acid (HA) followed by neutralization with sodium bicarbonate (SB) might modify rumen fermentation patterns and microbiota, thereby decreasing the negative effects of HCD. This study was thus aimed to investigate the effects of treatment of corn with 1% HA and subsequent neutralization with SB on rumen fermentation and microbiota, inflammatory response and growth performance in beef cattle fed HCD. Eighteen beef cattle were randomly allocated to three groups and each group was fed different diets: low-concentrate diet (LCD) (concentrate : forage = 40 : 60), HCD (concentrate : forage = 60 : 40) or HCD based on treated corn (HCDT) with the same concentrate to forage ratio as the HCD. The corn in the HCDT was steeped in 1% HA (wt/wt) for 48 h and neutralized with SB after HA treatment. The animal trial lasted for 42 days with an adaptation period of 7 days. At the end of the trial, rumen fluid samples were collected for measuring ruminal pH values, short-chain fatty acids, endotoxin (or lipopolysaccharide, LPS) and bacterial microbiota. Plasma samples were collected at the end of the trial to determine the concentrations of plasma LPS, proinflammatory cytokines and acute phase proteins (APPs). The results showed that compared with the LCD, feeding the HCD had better growth performance due to a shift in the ruminal fermentation pattern from acetate towards propionate, butyrate and valerate. However, the HCD decreased ruminal pH and increased ruminal LPS release and the concentrations of plasma proinflammatory cytokines and APPs. Furthermore, feeding the HCD reduced bacterial richness and diversity in the rumen. Treatment of corn increased resistant starch (RS) content. Compared with the HCD, feeding the HCDT reduced ruminal LPS and improved ruminal bacterial microbiota, resulting in decreased inflammation and improved growth performance. In conclusion, although the HCD had better growth performance than the LCD, feeding the HCD promoted the pH reduction and the LPS release in the rumen, disturbed the ruminal bacterial stability and increased inflammatory response. Treatment of corn with HA in combination with subsequent SB neutralization increased the RS content and helped counter the negative effects of feeding HCD to beef steers.
Although the deviations of brain volume deficits in sporadic and familial first-episode schizophrenia patients (FEP) had been presented, the difference of brain asymmetries remained unidentified.
To assess the potential differences of volumetric asymmetries of gray matter (GM) and white matter (WM) between groups.
To find out the different injury alteration of sporadic FEP and familial FEP.
42 sporadic and 30 familiar drug-naïve FEP with and 72 matched normal controls (NC) were recruited. Participants were assessed with neuropsychological tests and scanned by a 3.0T MRI to obtain T1-weighted and DTI images. Lateralization distribution maps of GM and WM volume were generated by employing optimized voxel-based morphometry. The asymmetries were analyzed by comparing calculating Laterality Index (LI) voxel by voxel.
All three groups showed similar overall brain torque. Familiar FEP have more regional extensive GM asymmetry brain lesions compared to sporadic FEP. There was no shared regional lesion between two groups. LIGM and LIWM in right superior temporal were negatively correlated. Significant negative correlations were also found between LIGM of left superior parietal lobule and LIWM of right superior parietal lobule, and between LIGM of right inferior parietal lobule and LIWM of left inferior parietal lobule. The asymmetry in distinct brain regions were related to cognitive deficits especially in the domains of language and memory.
The two patient groups had different alteration in injuries of brain asymmetry. Familiar FEP has more GM extensive asymmetry brain region, which may correlate with their high genetic burdens.
Multiple neurotrophic factors, including vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-2, nerve growth factor (NGF) and insulin-like growth factor(IGF)-1, have been shown to play important roles in the pathophysiology of mood disorders. However, insufficient clinical data supporting the importance of these neurotrophic factors in mood disorders, especially manic episode, have made inconclusive to make a connection between these factors and the disorder.
This study intended to investigate possible peripheral biomarkers in serum of manic episode of bipolar disorder.
We aimed to investigate whether or not serum levels of VEGF, FGF-2, NGF and IGF-1 varied in manic state.
Serum levels of VEGF, FGF-2, NGF and IGF-1 were examined in 70 drug-naïve patients with manic episode of bipolar disorder (BM) as well as 50 healthy controls, using an ELISA method.
The mean serum levels of VEGF, FGF-2, NGF and IGF-1 were 168.13±225.61pg/ml, 279.09±378.62pg/ml, 61.38±171.67pg/ml and 162.01±72.00ng/ml in BM patients, and 140.80±143.71pg/ml, 275.46±235.29pg/ml, 36.34±15.14pg/ml and 138.90±80.11ng/ml in healthy controls, respectively. Serum levels of FGF-2, NGF and IGF-1 in patients were significantly higher than those in healthy controls (Z=−2.896, P=0.004; Z=− 2.050, P=0.040; Z=−2.188, P=0.029; respectively), although there was no statistical difference in the serum levels of VEGF between two groups (Z=-0.468, P=0.639). Moreover, serum levels of NGF in patients correlated with the duration of disorder (rs=−0.241, P=0.044).
The increase in serum levels of FGF-2, NGF and IGF-1 in manic state may reflect a neuroprotective role for these factors, and these factors may be considered biological markers for manic episode.
Here, we explored the influences of dietary inulin (INU) supplementation on growth performance and intestinal health in a porcine model. Thirty-two male weaned pigs (with an average body weight of 7·10 (sd 0·20) kg) were randomly assigned to four treatments and fed with a basal diet (BD) or BD containing 2·5, 5·0 and 10·0 g/kg INU. After a 21-d trial, pigs were killed for collection of serum and intestinal tissues. We show that INU supplementation had no significant influence on the growth performance in weaned pigs. INU significantly elevated serum insulin-like growth factor-1 concentration but decreased diamine oxidase concentration (P < 0·05). Interestingly, 2·5 and 5·0 g/kg INU supplementation significantly elevated the villus height in jejunum and ileum (P < 0·05). Moreover, 2·5 and 5·0 g/kg INU supplementation also elevated the villus height to crypt depth (V:C) in the duodenum and ileum and improved the distribution and abundance of tight-junction protein zonula occludens-1 in duodenum and ileum epithelium. INU supplementation at 10·0 g/kg significantly elevated the sucrase activity in the ileum mucosa (P < 0·05). INU supplementation decreased the expression level of TNF-α but elevated the expression level of GLUT 2 and divalent metal transporter 1 in the intestinal mucosa (P < 0·05). Moreover, INU increased acetic and butyric acid concentrations in caecum (P < 0·05). Importantly, INU elevated the Lactobacillus population but decreased the Escherichia coli population in the caecum (P < 0·05). These results not only indicate a beneficial effect of INU on growth performance and intestinal barrier functions but also offer potential mechanisms behind the dietary fibre-regulated intestinal health.
The aim of this study was to analyze the profile of chest injuries, oxygen therapy for respiratory failure, and the outcomes of victims after the Jiangsu tornado, which occurred on June 23, 2016 in Yancheng City, Jiangsu Province, China.
The clinical records of 144 patients referred to Yancheng City No.1 People’s Hospital from June 23 through June 25 were retrospectively investigated. Of those patients, 68 (47.2%) sustained major chest injuries. The demographic details, trauma history, details of injuries and Abbreviated Injury Scores (AIS), therapy for respiratory failure, surgical procedures, length of intensive care unit (ICU) and hospital stay, and mortality were analyzed.
Of the 68 patients, 41 (60.3%) were female and 27 (39.7%) were male. The average age of the injured patients was 57.1 years. Forty-six patients (67.6%) suffered from polytrauma. The mean thoracic AIS of the victims was calculated as 2.85 (SD = 0.76). Rib fracture was the most common chest injury, noted in 56 patients (82.4%). Pulmonary contusion was the next most frequent injury, occurring in 12 patients (17.7%). Ten patients with severe chest trauma were admitted to ICU. The median ICU stay was 11.7 (SD = 8.5) days. Five patients required intubation and ventilation, one patient was treated with noninvasive positive pressure ventilation (NPPV), and four patients were treated with high-flow nasal cannula (HFNC). Three patients died during hospitalization. The hospital mortality was 4.41%.
Chest trauma was a common type of injury after tornado. The most frequent thoracic injuries were rib fractures and pulmonary contusion. Severe chest trauma is usually associated with a high incidence of respiratory support requirements and a long length of stay in the ICU. Early initiation of appropriate oxygen therapy was vital to restoring normal respiratory function and saving lives. Going forward, HFNC might be an effective and well-tolerated therapeutic addition to the management of acute respiratory failure in chest trauma.
This paper presents an investigation of the precise point positioning (PPP) performance of a combined solution from BDS-2 and BDS-3 satellites. To simultaneously process different BDS signal observations, i.e., B1/B1C, B2/B2a and B3C, undifferenced and uncombined observations with ionosphere delay constrained by the deterministic plus stochastic ionosphere model are used in the basic model. Special attention is paid to code bias and receiver clock parameters in the derivation of the observation model. The analysis is carried out using more than one-month data for BDS-2 and BDS-3 collected at the CANB, DWIN, KNDY and PETH stations in the Asia-Pacific region. The results suggest that compared with BDS-2 alone, the BDS-2 and BDS-3 solution provides significantly more accurate PPP, with increases of 28%, 21% and 5% in the up, north and east directions, respectively. In addition, the average root mean square error decreases to 0·21, 0·13 and 0·16 m for the three directions. Furthermore, the PPP convergence time for BDS-2 and BDS-3 is about 1·5 h and less than 1 h for the horizontal and vertical components, respectively, whereas that for BDS-2 alone is about 2·3 h for both directions.
To summarize characteristics and commonalities of non-technical competency frameworks for health professionals in emergency and disaster.
An electronic literature search was conducted in PubMed, MEDLINE, ERIC, Scopus, Cochrane database, and Google Scholar to identify original English-language articles related to development, evaluation or application of the nontechnical competency frameworks. Reviewers assessed identified articles for exclusion/inclusion criteria and abstracted data on study design, framework characteristics, and reliability/validity evidence.
Of the 9627 abstracts screened, 65 frameworks were identiﬁed from 94 studies that were eligible for result extraction. Sixty (63.8%) studies concentrated on clinical settings. Common scenarios of the studies were acute critical events in hospitals (44;46.8%) and nonspecified disasters (39;41.5%). Most of the participants (76; 80.9%) were clinical practitioners, and participants in 36 (38.3%) studies were multispecialty. Thirty-three (50.8%) and 42 (64.6%) frameworks had not reported evidence on reliability and validity, respectively. Fourteen of the most commonly involved domains were identified from the frameworks.
Nontechnical competency frameworks applied to multidisciplinary emergency health professionals are heterogeneous in construct and application. A fundamental framework with standardized terminology for the articulation of competency should be developed and validated so as to be accepted and adapted universally by health professionals in all-hazard emergency environment.
We compared the electrical conductivity from two different aggregates of whey protein concentrates (WPC) film: conventional amorphous aggregation at natural pH (pH 6.5) and amyloid fibrils at a low pH (pH 2.0) far away from the isoelectric point. The two types of film fabricated by these solutions with different aggregate structures showed large variations in electrical conductivity and other properties. The WPC fibril film (pH 2.0) exhibited higher electrical conductivity than that of the conventional WPC film (pH 6.5), improved mechanical properties and oil resistance, due to varying morphology, higher surface hydrophobicity and more (absolute value) surface charge of film-forming solutions. The evidence from this study suggests that fibrilized WPC with high-ordered and β-sheets-rich structures fabricated high electrical conductivity film, which broadens the potential application of fibrils as functional bio-nanomaterials.
Schizophrenia is a common major mental disorder and prenatal nutritional deficiency may increase its risk. We aimed to investigate long-term impact of prenatal exposure to malnutrition on risk of schizophrenia in adulthood using the Chinese famine of 1959–1961 as a natural experiment.
We obtained data from the Second National Sample Survey on Disability implemented in 31 provinces in 2006, and restricted our analysis to 387,093 individuals born from 1956 to 1965. Schizophrenia was ascertained by psychiatrists based on the International Statistical Classification of Diseases, Tenth Revision. Famine severity was defined as cohort size shrinkage index. The famine effect on adult schizophrenia was estimated by difference-in-difference models, established by examining the variations of famine exposure across birth cohorts.
Compared with the reference cohort of 1965, famine cohorts (1959–1962) had significantly higher odds (OR: 1.84; 95% CI: 1.13, 3.00; P = 0.014) of schizophrenia in the rural population. After adjusting for multiple covariates, this association remained significant (OR: 1.82; 95% CI: 1.11, 2.98; P = 0.018). We did not observe statistically significant differences in odds of schizophrenia among famine cohorts compared with the reference cohort in the urban population.
Prenatal malnutrition exposure has a detrimental impact on risk of schizophrenia in adulthood in the rural population. Further studies were needed to investigate corresponding mechanisms on this topic.