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Hand, foot and mouth disease (HFMD) has spread widely and leads to high disease burden in many countries. However, relative transmissibility from male to female individuals remains unclear. HFMD surveillance database was built in Shenzhen City from 2013 to 2017. An intersex transmission susceptible–infectious–recovered model was developed to calculate the transmission relative rate among male individuals, among female individuals, from male to female and from female to male. Two indicators, ratio of transmission relative rate (Rβ) and relative transmissibility index (RTI), were developed to assess the relative transmissibility of male vs. female. During the study period, 270 347 HFMD cases were reported in the city, among which 16 were death cases with a fatality of 0.0059%. Reported incidence of total cases, male cases and female cases was 0.0057 (range: 0.0036–0.0058), 0.0052 (range: 0.0032–0.0053) and 0.0044 (range: 0.0026–0.0047), respectively. The difference was statistically significant between male and female (t = 3.046, P = 0.002). Rβ of male vs. female, female vs. female, from female to male vs. female and from male to female vs. female was 7.69, 1.00, 1.74 and 7.13, respectively. RTI of male vs. female, female vs. female, from female to male vs. female and from male to female vs. female was 3.08, 1.00, 1.88 and 1.43, respectively. Transmissibility of HFMD is different between male and female individuals. Male cases seem to be more transmissible than female.
The intracellular concentration of calcium ion ([Ca2+]i) is a critical regulator of cell signaling and contractility of vascular smooth muscle cells (VSMCs). In this study, we employed an atomic force microscopy (AFM) nanoindentation-based approach to investigate the role of [Ca2+]i in regulating the cortical elasticity of rat cremaster VSMCs and the ability of rat VSMCs to adhere to fibronectin (Fn) matrix. Elevation of [Ca2+]i by ionomycin treatment increased rat VSMC stiffness and cell adhesion to Fn-biofunctionalized AFM probes, whereas attenuation of [Ca2+]i by 1,2-Bis (2-aminophenoxy)ethane-N,N,N’,N’-tetraacetic acid tetrakis (acetoxymethyl ester) (BAPTA-AM) treatment decreased the mechanical and matrix adhesive properties of VSMCs. Furthermore, we found that ionomycin/BAPTA-AM treatments altered expression of α5 integrin subunits and α smooth muscle actin in rat VSMCs. These data suggest that [Ca2+]i regulates VSMC elasticity and adhesion to the extracellular matrix by a potential mechanism involving changing dynamics of the integrin–actin cytoskeleton axis.
The evolution of fatigue performance and surface mechanical properties of AISI 304 stainless steel induced by the electropulsing-assisted ultrasonic surface rolling process (EP-USRP) was systematically investigated by integrating instrumented indentation, scanning electron microscopy with electron backscatter diffraction, and transmission electron microscopy. The results indicate that higher hardness, greater strength, finer ultra-refined grains, and higher residual compressive stress are formed within the strengthened layer compared with the original ultrasonic surface rolling process (USRP). EP-USRP with the optimized experimental parameters can produce a higher average rotating bending fatigue strength for AISI 304 stainless steel than USRP. Anomalously and noteworthily, all fatigue specimens treated by EP-USRP showed an incomplete fracture, revealing a higher reservation of safety in practical engineering applications. The further modified structure strengthening and stress strengthening induced by EP-USRP are likely the primary intrinsic reasons for the observed phenomena. Furthermore, the influence mechanism of EP-USRP was discussed scrupulously.
Training students has been proven to be the optimal way to deliver cardiopulmonary resuscitation (CPR) skills. However, it is somehow unknown whether or not the current recommendations appropriate for Caucasian students are also suitable for East Asian students. The purpose of this study is to explore the best age for East Asian students to receive CPR training.
Students were recruited from six schools. Students participated in a standard CPR training program provided by tutors. Each student attended a 60-minute training session with a manikin. After being trained, within one hour, the student’s compression quality was assessed.
A total of 360 students who constituted 12 continuous grades were recruited for this study. Adequate compression depth and satisfactory compression rate with correct hand position could be achieved since the age of 12. However, successful compression rate and complete release could be achieved since the younger age of six.
Current recommendations for Caucasian students to cultivate a full-capacity CPR rescuer at the age of 12 are also appropriate for East Asian students. However, the optimal age for students to receive CPR training should be decided based on evidence and importance assessment of CPR.
He D, Huang K, Yang Y, Jiang W, Yang N, Yang H. What is the optimal age for students to receive cardiopulmonary resuscitation training? Prehosp Disaster Med. 2018;33(4):394–398.
Pilophyllia Ge and Yu, 1974 represents a major group of distinctive amplexoid corals in the Silurian, whose taxonomic relationships, species composition, and evolutionary trends remain contentious. A critical revision of type material and new specimens of several species (and subspecies) assigned to Pilophyllia, including the type species P. involuta Ge and Yu, 1974, provides solutions to some of these problems. Pilophyllia is revised to include only those forms characterized by a distinct peripheral stereozone and amplexoid major septa with club-shaped rhabdacanths set in thick lamellar stereomes. Other species, previously referred to Pilophyllia but having generally short septa with wedge-shaped rhabdacanths, are transferred herein to the new genus Neopilophyllia Wang. Both genera, together with other Silurian amplexoid rugosan genera such as Amplexoides, are referred to the new family Amplexoididae Wang, which is thought to be evolutionarily unrelated to the much younger (Devonian to early Carboniferous) amplexoid rugosan family Amplexidae Chapman, 1893. The first appearance of Neopilophyllia n. gen. in the middle Telychian, much later than that of Pilophyllia in the late Rhuddanian, probably marks a significant stage during the evolution of Silurian amplexoid corals.
For the first time, an experiment has been conducted to investigate synthetic jet laminar vortex rings impinging onto porous walls with different geometries by time-resolved particle image velocimetry. The geometry of the porous wall is changed by varying the hole diameter on the wall (from 1.0 mm to 3.0 mm) when surface porosity is kept constant (
). The finite-time Lyapunov exponent and phase-averaged vorticity field derived from particle image velocimetry data are presented to reveal the evolution of the vortical structures. A mechanism associated with vorticity cancellation is proposed to explain the formation of downstream transmitted vortex rings; and both the vortex ring trajectory and the time-mean flow feature are compared between different cases. It is found that the hole diameter significantly influences the evolution of the flow structures on both the upstream and downstream sides of the porous wall. In particular, for a porous wall with a small hole diameter (
, 0.10 and 0.133), the transmitted finger-type jets will reorganize into a well-formed transmitted vortex ring in the downstream flow. However, for the case of a large hole diameter of
, the transmitted vortex ring is not well formed because of insufficient vorticity cancellation. Additionally, the residual vorticity gradually evolves into discrete jet-like structures downstream, which further weaken the intensity of the transmitted vortex ring. Consequently, the transmitted flow structures for the
case would lose coherence more easily (or probably even transition to turbulence), resulting in a faster decay of the axial velocity and stronger entrainment of the transmitted jet. For all porous wall cases, the velocity profile of the transmitted jet exhibits self-similar behaviour in the far field (
), which agrees well with the velocity distribution of free synthetic jets. With the help of the control-volume approach, the time-mean drag of the porous wall is evaluated experimentally for the first time. It is shown that the porous wall drag increases with the decrease in the hole diameter. Moreover, for a porous wall with a small hole diameter (
, 0.10 and 0.133), it appears that the porous wall drag mainly derives from the viscous effect. However, as
increases to 0.20, the form drag associated with the porous wall geometry becomes significant.
Drawing from self-concept and implicit leadership theories, we propose a multilevel model to examine whether, why, and when self-sacrificial leadership motivates followers’ affiliative and challenging citizenship behaviors in China. Data from 329 full-time employees in 83 work groups provide support for the hypothesized model. Specifically, we demonstrated that self-sacrificial leadership was positively related to followers’ relational self-concept constructs of leader identification and leader-based self-esteem, which had differential, downstream implications for followers’ two types of citizenship behavior. Whereas leader identification was found to mediate the positive relationship between self-sacrificial leadership and affiliative citizenship behavior only, leader-based self-esteem mediated the positive relationships of self-sacrificial leadership with both affiliative and challenging citizenship behaviors. We further demonstrated individual power distance orientation as a significant cultural contingency in the above mediation relationships, which were found to exist among followers with low rather than high power distance orientations. We conclude by discussing the theoretical and practical implications of these findings.
The predictability of modified constitutive model, based on Arrhenius type equation, for illustrating the flow behavior of Fe–36%Ni Invar alloy was investigated via isothermal hot compression tests. The hot deformation tests were carried out in a temperature range of 850–1100 °C and strain rates from 0.01 to 10 s−1. True stress-true strain curves exhibited the dependence of the flow stress on deformation temperatures and strain rates, which then described in Arrhenius-type equation by Zener–Holloman parameter. Moreover, the related material constants and hot deformation activation energy (Q) in the constitutive model were calculated by considering the effect of strain as independent function on them and employing sixth polynomial fitting. Subsequently, the performance of the modified constitutive equation was verified by correlation coefficient and average absolute relative error which were estimated in accordance with experimental and predicted data. The results showed that the modified constitutive equation possess reliable and stable ability to predict the hot flow behavior of studied material under different deformation conditions. Meanwhile, Zener–Holloman parameter map was established according to the modified constitutive equation and used to estimate the extent of dynamic recrystallization.
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.
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.
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
Cancer patients with depression or anxiety have poor survival, and the interaction between mental and physical problems in older patients may exacerbate this problem. K-ras oncogene (KRAS) mutation may play a role in the development of psychosocial distress and may be associated with poor survival of metastatic colorectal cancer (mCRC) patients. This study investigated the association between KRAS gene mutations and psychosocial morbidity to explore the possible cancer/psychosis relationship in older mCRC patients.
In this study, 62 newly diagnosed mCRC patients were recruited and completed the Hospital Anxiety and Depression Scale (HADS). Demographic data were also collected, and clinicopathological data were retrieved from medical records. KRAS mutations were assessed via PCR analysis of tissue specimens from the patients.
The results showed that 28 of the 62 participants (45.2%) had positive screens for possible depression, and 45 of the 62 participants (72.6%) had positive screens for anxiety. The KRAS mutation rate was 40.3% (25/62), and 19 of the 25 patients with KRAS mutations (76.0%) had probable depression, whereas only 24.3% of the patients with wild-type KRAS were probably depressed (p < 0.05). The KRAS mutation was associated with higher HADS depression scores, independent of gender and performance status (p < 0.05), but not with higher HADS anxiety or total scores.
KRAS mutations were associated with depression severity and higher rates of probable depression in older mCRC patients. Depression should be assessed and treated as early as possible in older mCRC patients with the KRAS mutation. Further studies are needed to verify our current findings using a larger sample size.
The present study was performed to identify the genotype of a hypertrophic cardiomyopathy family and investigate the clinicopathogenic characteristics and prognostic features of relevant genetic abnormalities. Target sequence capture sequencing was performed to screen for pathogenic alleles in a 32-year-old female patient (proband). Sanger sequencing was carried out to verify the results. Sanger sequencing was also performed on other family members to identify allele carriers. A survival analysis was carried out using published literature and our findings. We found that the proband and her son harboured a Gly716Arg sequence variant of the β-myosin heavy chain. Neither the proband’s father nor the mother were carriers of this sequence variant; thus, the mutation was classified as “de novo”. Further survival analysis revealed that female patients appear to have a longer life expectancy compared with males. Our study may provide an effective approach for the genetic diagnosis of hypertrophic cardiomyopathy.
A 100-J-level Nd:glass laser system in nanosecond-scale pulse width has been constructed to perform as a standard source of high-fluence-laser science experiments. The laser system, operating with typical pulse durations of 3–5 ns and beam diameter 60 mm, employs a sequence of successive rod amplifiers to achieve 100-J-level energy at 1053 nm at 3 ns. The frequency conversion can provide energy of 50-J level at 351 nm. In addition to the high stability of the energy output, the most valuable of the laser system is the high spatiotemporal beam quality of the output, which contains the uniform square pulse waveform, the uniform flat-top spatial fluence distribution and the uniform flat-top wavefront.
In this paper, we propose a new algebraic method to construct non-autonomous discrete integrable systems. The method starts from constructing generalizations of convergence acceleration algorithms related to discrete integrable systems. Then the non-autonomous version of the corresponding integrable systems are derived. The molecule solutions of the systems are also obtained. As an example of the application of the method, we propose a generalization of the multistep ϵ-algorithm, and then derive a non-autonomous discrete extended Lotka–Volterra equation. Since the convergence acceleration algorithm from the lattice Boussinesq equation is just a particular case of the multistep ϵ-algorithm, we have therefore arrived at a generalization of this algorithm. Finally, numerical experiments on the new algorithm are presented.
Nanogenerators (NGs) have great potential to solve the problems of energy depletion and environmental pollution. Here, two types of flexible nanogenerators (FNGs) based on graphene oxide (GO) and multiwall carbon nanotubes (MW-CNTs) are presented. The peak output voltage and current of GO based FNG reached up to 2 V and 30 nA, respectively, under 15 N force at 1 Hz. Moreover, the output voltage could be improved to 34.4 V when the frequency was increased to 10 Hz. It was also found the output voltage increased from 0.1 V to 2.0 V using a released GO structure. The other FNG was made by MW-CNTs mixed with ZnO nanoparticles (NPs). Its output voltage and power reached up to 7.5 V and 18.75 mW, respectively, which is much larger than that of bare ZnO based FNG. Furthermore, a peak voltage of 30 V could be gained by stamping one’s foot on the FNG. Finally, a modified NG was fabricated using four springs and two flexible layers. As a result, the voltage and power reached up to 9 V and 27mW, respectively. These works may bring out broad applications in energy harvesting.
The effects of Fe2B-grain orientation on microstructure and properties of bulk Fe2B intermetallic fabricated by directional and ordinary solidification techniques have been investigated. The results show that unidirectional solidified Fe2B intermetallic possesses a strong (002) texture in the transverse direction owing to the opposite unidirectional heat-squeeze effect while random Fe2B grains can be produced under ordinary solidification conditions. The nonoriented Fe2B intermetallic has the highest linear expansion coefficient of 13.04 × 10−6 °C−1 while the microhardness and fracture toughness of transverse Fe2B intermetallic in the (002) plane are larger than those of Fe2B with other grain orientations and their values are ∼18.72 GPa and 6.42 MPa·m1/2, respectively. Liquid zinc corrosion results indicate that unidirectional Fe2B intermetallic with long axis perpendicular to the direction of liquid zinc corrosion displays the best corrosion resistance to liquid zinc owing to its beneficial barrier effect. The FeB transition phase can naturally form and grow parabolically during liquid zinc corrosion.
The association between serum carotenoids and the metabolic syndrome (MetS) remains uncertain, and little is known about this relationship in the Chinese population. The present study examined the association between serum carotenoid concentrations and the MetS in Chinese adults. We conducted a community-based cross-sectional study in which 2148 subjects (1547 women and 601 men) aged 50–75 years were recruited in urban Guangzhou, China. Dietary data and other covariates were collected during face-to-face interviews. Blood pressure, waist circumference, blood lipids, glucose and serum carotenoids (α-, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin) were examined. We found dose–response inverse relationships between individual serum carotenoid concentrations and total carotenoids and the prevalence of the MetS after adjusting for potential confounders (P for trend < 0·001). The OR of the MetS for the highest (v. lowest) quartile were 0·31 (95 % CI 0·20, 0·47) for α-carotene, 0·23 (95 % CI 0·15, 0·36) for β-carotene, 0·44 (95 % CI 0·29, 0·67) for β-cryptoxanthin, 0·39 (95 % CI 0·26, 0·58) for lycopene, 0·28 (95 % CI 0·18, 0·44) for lutein+zeaxanthin and 0·19 (95 % CI 0·12, 0·30) for total carotenoids. Higher concentrations of each individual carotenoid and total carotenoids were significantly associated with a decrease in the number of abnormal MetS components (P for trend < 0·001–0·023). Higher serum carotenoid levels were associated with a lower prevalence of the MetS and fewer abnormal MetS components in middle-aged and elderly Chinese adults.
We present rational computational design of phenothiazine dyes for dye-sensitized solar cells containing different five-membered rings (thiophene, furan, and selenophene) by a combined strategy of modified conjugation order and functionalization leading to the quinoidization of the ring. We predict that it is possible to lower the excitation energy by 20% vs. the parent dye by the combination of: change in the conjugation order of the methine unit, its functionalization by the CN group, and replacement of the thiophene ring by furan.
Common psychiatric disorders are highly heritable, indicating that genetic factors play an important role in their aetiology. The CACNA1C gene, which codes for subunit alpha-1C of the Cav1.2 voltage-dependent L-type calcium channel, has been consistently found to be the shared risk gene for several kinds of mental disorder.
To investigate whether CACNA1C is a susceptibility gene for schizophrenia and major depressive disorder in the Han Chinese population.
We carried out a case–control study of 1235 patients with schizophrenia, 1045 with major depressive disorder and 1235 healthy controls. A tag single nucleotide polymorphism (SNP) rs1006737 along with another 10 tag SNPs in the CACNA1C gene were genotyped in all samples.
We found that rs1006737 was associated with both schizophrenia (Pallele = 0.0014, Pgenotype = 0.006, odds ratio (OR) = 1.384, 95% CI 1.134–1.690) and major depressive disorder (Pallele = 0.0007, Pgenotype = 0.003, OR = 1.425, 95% CI 1.160–1.752).
Our findings support CACNA1C being a risk gene for both schizophrenia and major depressive disorder in the Han Chinese population.