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Ta–W co-alloying was realized by double glow plasma surface metallurgy technology, and their effects on high-temperature oxidation behavior of γ-TiAl were studied. Ta–W co-alloying coating was composed of a deposited layer and interdiffusion layer. The results of isothermal oxidation experiment indicated that a compact mixed oxide film of Ta and W was formed on the sample. The interdiffusion layer reduced the oxygen intrusion that improved the high-temperature oxidation resistance of γ-TiAl. The effects of Ta–W co-alloying on oxygen adsorption energy and electronic structure of γ-TiAl(111) were analyzed by first-principle calculation. The results showed that the optimal adsorption sites of O atoms changed from fcc-Al to hcp-Ti and hcp-Al, indicating that Ta–W co-alloying inhibited the diffusion of O. The electronic structure analysis of γ-TiAl(111) after Ta–W alloying indicated the affinity of Ti and O was inhibited, which resulted in decreased TiO2 in the oxide film.
A facile and low-cost method based for tension gradient self-assembly was developed to prepare polytetrafluoroethylene (PTFE) nanofiber coatings on stainless-steel fiber felts. The PTFE particles were used as building blocks and the self-assembly process was analyzed thoroughly. After being sintered, the PTFE particles were transformed into PTFE nanofibers. The felts coated with the PTFE nanofibers exhibited superhydrophobicity and superoleophilicity, and could separate a series of oil–water mixtures with high efficiency and good reusability. The coated felts also presented excellent chemical and thermal stabilities. Over all, this approach could easily fabricate ultra-robust oil–water separation materials suitable for industrial applications.
Liquid films can be entrained when the dewetting velocity attains a threshold, and this dynamical wetting transition has been well studied in the situation of plane substrates. We investigate the forced dewetting in a capillary tube using diffuse-interface simulations and lubrication analysis, focusing on the onset of wetting transition and subsequent interface evolution. Results show that the meniscus remains stable when the displacing rate is below a threshold, beyond which film entrainment occurs and eventually leads to the formation of Taylor bubbles separated by liquid slugs, as has also been observed in the recent experiments of Zhao et al. (Phys. Rev. Lett., vol. 120, 2018, 084501). We derive an analytical solution of the critical capillary number, and demonstrate that the wetting transition is accompanied by a vanishing apparent contact angle and an abrupt drop of the contact-line velocity. Both the bubble and slug lengths are found to depend on the capillary number and the wettability of the wall. A theoretical formula for the bubble length is also proposed and compares favourably with numerical and experimental results.
Nanocarbons have been catalytically grown since 1993. However, even today, the formation mechanisms of carbon nanotubes (CNTs) and graphene are not sufficiently understood. This sustained challenge has been an engine for the development in theory concepts and computational methods, tackling the problem of well-controlled production of these nanomaterials. This article discusses how experimental discoveries and theoretical approaches evolved hand-in-hand for the successful understanding of challenging issues, highlighting parallels and distinctions between graphene and CNTs. Key aspects include the mechanisms of nucleation and CNT-liftoff, chiral symmetry selection and control, rates of growth and island shapes, mechanisms defining single chirality of the nanotubes, and ways to suppress grain boundaries in the quest for ever larger and faster growing single-crystal graphene, or longest defect-free CNTs. The theme of catalyst chemistry and structure, either as a nanoparticle or a planar substrate, is traced through the stages of nanocarbon formation, with focus on theoretically generalizable findings.
The sea cucumber Apostichopus japonicus is a deposit-feeder and vital for marine benthic ecosystems. Hypoxia can influence the behaviour and even lead to massive mortality in A. japonicus in the wild. It is important to understand the molecular responses of A. japonicus when exposed to acute changes in dissolved oxygen (DO) concentration. In this study, RNA-seq provided a general overview of the gene expression profiles of the respiratory tree of A. japonicus exposed to DO of 8 mg l−1 (DO8), 4 mg l−1 (DO4) and 2 mg l−1 (DO2) conditions. Differentially expressed genes (DEGs) screening with the NOISeq method identified 51, 59 and 61 DEGs according to the criteria of fold change ≥2 and divergence probability ≥0.8 in the comparisons of DO2 vs DO4, DO2 vs DO8 and DO4 vs DO8, respectively. Gene ontology analysis showed that ‘cellular process’ and ‘binding’ had the most enriched DEGs in the categories of ‘biological process’ and ‘molecular function’, respectively (catalytic activity also had the most enriched DEGs in the category of ‘molecular function’ based on the comparison of DO2 vs DO8), while ‘cell’ and ‘cell part’ had the most enriched DEGs in the category of ‘cellular component’. The DEGs were mapped to 79, 81 and 104 pathways in the KEGG database, and 8, 29 and 16 pathways were significantly enriched, respectively. The DO-specific DEGs identified in this study of the respiratory tree are important targets for further research into the biochemical mechanisms involved in the response of the sea cucumber to changes in the DO concentration.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
To retrospectively analyze the rescue and treatment of pediatric patients by the Chinese Red Cross medical team during the Nepal earthquake relief.
The medical team set up a field hospital; the pediatric clinic consisted of 1 pediatrician and several nurses. Children younger than 18 years old were placed in the pediatric clinic for injury examination and treatment.
During the 7-day period of medical assistance (the second to third week after the earthquake), a total of 108 pediatric patients were diagnosed and treated, accounting for 2.8% of the total patients. The earthquake-related injuries mainly required surgical dressing and debridement. No severe limb fractures or traumatic brain injuries were found. Infection of the respiratory tract, the gastrointestinal tract, and the skin were the most common ailments, accounting for 42.3%, 18.5%, and 16.7%, respectively, of the total treated patients.
Two to 3 weeks after the earthquake, the admitted pediatric patients mainly displayed respiratory and gastrointestinal infections. When developing a rescue plan and arranging medical resources, we should consider the necessity of treating non–disaster-related conditions. (Disaster Med Public Health Preparedness. 2016;page 1 of 4)
On April 25, 2015, a massive 8.1-magnitude earthquake struck Nepal at 2:11 pm (Beijing time). The 68-member-strong China International Search & Rescue Team (CISAR) left for Nepal at 6 am, April 26, to help with relief work. The CISAR was the first foreign team to rescue a survivor who was trapped beneath the rubble in the Gongabu area after the earthquake. On May 8, the team fulfilled the search-and-rescue mission and returned to Beijing. During the 2 weeks of rescue work, the team treated more than 3700 victims and cleared approximately 430 buildings. In this rescue mission, 10 experienced medical officers (including nine doctors and a nurse) from the General Hospital of Chinese People’s Armed Police Force (PAP) comprised the medical team of CISAR. In this report, we focus on the medical rescues by CISAR and discuss the characteristics of the medical rescue in Nepal. (Disaster Med Public Health Preparedness. 2018;12:536–538)
Arctic shipping routes attract more and more attention because of the increasing possibility to build commercial shipping routes which connect East Asia and Western Europe. To build profitable commercial shipping routes, shipping companies should study many issues about the Arctic carefully since it is a new and unfamiliar frontier. To find out key factors influencing the building of Arctic shipping routes, the authors applied the fuzzy Analytic Hierarchy Process (AHP) model in this study. Based on the AHP experts’ questionnaires, we applied the fuzzy AHP model to analyse the opinions of respondents. This article presents the results of an empirical survey conducted among shipping companies and academic researchers with ship captain experience to explore their attitudes toward the building of Arctic shipping routes. The findings showed that: ‘Safety and risk’ is the most important aspect affecting the building of Arctic shipping routes and in order of relative importance, the top six critical assessment factors are ‘navigation safety and risk analysis,’ ‘governance and cooperation,’ ‘navigation information,’ ‘cargo sources,’ ‘cost,’ and ‘navigator ability,’ respectively.
We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of age was 397,466. As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood. After adjusting the results for birth weight, the birth order differences decreased and were no longer statistically significant. First-born twins had greater BMI than the second-born twins over childhood and adolescence. After adjusting the results for birth weight, birth order was still associated with BMI until 12 years of age. No interaction effect between birth order and zygosity was found. Only limited evidence was found that birth order influenced variances of height or BMI. The results were similar among boys and girls and also in MZ and DZ twins. Overall, the differences in height and BMI between first- and second-born twins were modest even in early childhood, while adjustment for birth weight reduced the birth order differences but did not remove them for BMI.
We investigate the entrainment of liquid films on a partially wetting plate vertically withdrawn from a reservoir of viscous liquid using a combination of diffuse-interface numerical simulation and lubrication analysis. So far available theoretical investigations were commonly conducted by focusing on separate parameter regions, and a complete description of the flow regimes with increasing plate speed is still missing. By solving the full Stokes equations, we present a complete scenario of film transition in the presence of moving contact line. With increasing plate speed, we identify numerically four successive flow regimes in terms of the interfacial morphologies: (1) a stationary meniscus, (2) a speed-independent thick film connected to the liquid bath through a stationary dimple, (3) coexistence of a thick film and the classical Landau–Levich–Derjaguin (LLD) film connected by a propagating capillary shock and (4) a film with a monotonically varying thickness. The characteristics of the film profiles in different regions of the interfaces are analysed with lubrication theory as applicable, and satisfactory agreements with the numerical results are obtained. In particular, we confirm that the onset of film deposition occurs at a vanishing apparent contact angle, consistent with the predictions of lubrication theory. Numerical results suggest that the critical capillary number for the onset of film deposition is smaller than that for the onset of LLD film despite the fact that it is higher than the experimentally observed one, showing that the thick film can be realized in the two-dimensional model. We also demonstrated that the LLD film is triggered by the bifurcation of the stationary dimple, which is found to admit multiple branches of stable and unstable solutions.
Mussels are typical macrofouling organisms in the world. In this study, the interaction between the settlement of Mytilus coruscus plantigrades and bacterial community on coloured substrata was determined. Bacterial communities in biofilms developed on seven coloured substrata were analysed by Illumina Miseq sequencing. The mussel settlement response to coloured substrata with no biofilms was also examined. Flavobacteria, Alphaproteobacteria and Gammaproteobacteria were the first, second and third most dominant groups in seven biofilm samples. The results suggest that the inducing activities of these biofilms on plantigrade settlement varied with coloured substrata and the lowest percentage of settlement was observed on biofilms on the green substratum. High-throughput sequencing showed that bacterial community in biofilms also changed with the substratum colour. No significant difference in the inducing activity on plantigrade settlement was observed between the coloured substrata with no biofilms. Thus, difference in plantigrade settlement response may be correlated to the changes in bacterial community on coloured substrata. This finding extends current knowledge of interaction among mussel settlement and bacterial community variability.
Two transmission curved crystal spectrometers are designed to measure the hard x-ray emission in the laser fusion experiment of Compton radiography of implosion target on ShenGuang-III laser facility in China. Cylindrically curved
-quartz (10–11) crystals with curvature radii of 150 and 300 mm are used to cover spectral ranges of 10–56 and 17–100 keV, respectively. The distance between the crystal and the x-ray source can be changed over a broad distance from 200 to 1500 mm. The optical design, including the integral reflectivity of the curved crystal, the sensitivity, and the spectral resolution of the spectrometers, is discussed. We also provide mechanic design details and experimental results using a Mo anode x-ray source. High-quality spectra were obtained. We confirmed that the spectral resolution can be improved by increasing the working distance, which is the distance between the recording medium and the Rowland circle.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Two phases of nickel sulfide (α-NiS and β-NiS) nanoarchitectures were successfully and controllably synthesized by a facile solvothermal method with two different solvents of alcohol and water, respectively. The products were characterized by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectrophotometer. The sphere-like shape for α-NiS and cross-like shape composed of nanorods for β-NiS are uniform and well distributed as well as their size. Both α-NiS and β-NiS powders were used as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). It is found that the DSSC with an α-NiS CE performs much better than the one with a β-NiS CE. The energy conversion efficiency of the former was 5.2%, whereas the latter was 4.2%, about 20% increment.
Background: The present study examined the prospective relationships between subjective fatigue, cognitive function, and everyday functioning.
Methods: A cohort study with secondary data analysis was conducted using data from 2,781 community-dwelling older adults without dementia who were enrolled to participate in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) randomized intervention trial. Measures included demographic and health information at baseline, and annual assessments of subjective fatigue, cognitive function (i.e. speed of processing, memory, and reasoning), and everyday functioning (i.e. everyday speed and everyday problem-solving) over five years.
Results: Four distinct classes of subjective fatigue were identified using growth mixture modeling: one group complaining fatigue “some of the time” at baseline but “most of the time” at five-year follow-up (increased fatigue), one complaining fatigue “a good bit of the time” constantly over time (persistent fatigue), one complaining fatigue “most of the time” at baseline but “some of the time” at five-year follow-up (decreased fatigue), and the fourth complaining fatigue “some of the time” constantly over time (persistent energy). All domains of cognitive function and everyday functioning declined significantly over five years; and the decline rates, but not the baseline levels, differed by the latent class of subjective fatigue. Except for the decreased fatigue class, there were different degrees of significant associations between the decline rates of subjective fatigue and all domains of cognitive function and everyday functioning in other classes of subjective fatigue.
Conclusion: Future interventions should address subjective fatigue when managing cognitive and functional abilities in community-dwelling older adults.
In this study we investigated the importance of two species of fruit bat (Rousettus leschenaulti and Cynopterus sphinx) as seed dispersers for a species of fruit tree (Syzygium oblatum) found in the Xishuangbanna Tropical Botanical Garden in South-West China. We found that although R. leschenaulti and C. sphinx were the two primary seed dispersers of S. oblatum over half of the fruit produced by the tree (65%) fell to the ground. Out of the fruit collected, R. leschenaulti and C. sphinx were able to disperse seeds up to 73 m from the parent tree with the highest density of feeding roosts occurring at 21.3 m (SE = 5.2 m). We found no signs that either species of bat used the parent tree as a feeding roost, instead choosing specific trees that were at lower densities compared with other trees in the forest that were not used. When comparing the viability of seeds in three different habitats (under parent tree, in forest gap, under feeding roost) survival analysis revealed that seedling survival was significantly higher in the forest gap (91.7% ± 4.41%) than under the parent tree (78.3% ± 1.67%), but was not significantly different to seedling survival underneath feeding roosts (86.7 ± 1.67%). Further work also showed that the seeds did not have to be removed from the fruit or ingested by the bat in order to germinate. We conclude that although S. oblatum is not dependent on R. leschenaulti and C. sphinx for successful germination of its seeds, these two species of bat are important seed dispersers and can move seeds to areas where there is a greater chance of germination success and survival.