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Nacre-mimetic (PE/TiO2)4 nanolayered composites (NLCs) with the nanocrystalline TiO2 layer thickness less than 30 nm and different thickness ratios of inorganic/organic layers were successfully prepared by using layer-by-layer self-assembly and chemical bath deposition method. Mechanical properties, especially fatigue properties of the NLCs with different thickness ratios were evaluated. The elastic modulus, hardness and fracture toughness, strain amplitude to fatigue limits of the NLCs reached 27.78 ± 5.69 GPa, 1.33 ± 0.31 GPa, and 4.16 ± 0.20 MPa m1/2, respectively. Fatigue performance of the NLCs in the high and low cycle fatigue regimes was optimized by tailoring the thickness ratio of the TiO2/PE layers. The PE/TiO2 NLCs with the larger thickness ratio of ∼3 has the high fatigue limit (the critical strain amplitude of 0.0853%) in the high-cycle fatigue regime, while that with the smaller thickness ratio of ∼1 and ∼0.5 are of the good fatigue strength in the low-cycle fatigue regime. The basic mechanism for the enhanced fatigue performance is elucidated.

In the design process, different problem statements result in different problem-solving strategies. A proper problem statement is the key to effective problem-solving. Based on the characteristics of the product design process, we divided design problem statements into open-ended (OE), decision-making (DM), and constrained (CO) statements and attempted to investigate the influences of different problem statements on designers’ cognitive behaviors from three perspectives, namely divergent thinking, convergent thinking, and mental workload. Then we provided quantification description to these influences based on electroencephalography (EEG) technology. We conducted experiments on 19 participants and used the BrainProduct™ actiChamp-32 to record the EEG data. Results are as follows: (1) The higher task-related α power was found in the temporal and occipital regions in the OE task compared with that in the DM and CO tasks. The OE statement also would help designers get novel ideas by strengthening their divergent thinking. (2) In the DM and CO tasks, there was no significant difference in the impact of the brain region on convergent thinking, but activities in the left hemisphere were stronger than that in the right hemisphere. The DM and CO tasks have better performance in convergent thinking than the OE task. (3) In the CO task, the designer's mental workload is the highest and mainly related to the activation of the centroparietal and occipital regions. These findings help designers understand the design problem-solving process from the perspective of cognitive science and monitor their thinking modes in the design process so as to improve their design performance.

For countries faced with much talk but little action on healthcare reform, China’s National Health Guiding Principles (CNHGP), with its 60-year history, may provide a new perspective. There are four values of CNHGP for healthcare reform. First, these principles provide an innovative strategic framework for healthcare reform with three levels, from ‘One priority population’ to ‘Four approaches’ and then to ‘Two aims.’ The second is the importance of mass/grassroots participation, which runs through all three levels of CNHGP. The third value is that the CNHGP used nonspecific social approaches, an innovation in healthcare delivery that addressed the social determinants of health. The fourth value is the integration between Chinese traditional medicine and Western medicine.

Elemental mapping at the atomic-scale by scanning transmission electron microscopy (STEM) using energy-dispersive X-ray spectroscopy (EDS) provides a powerful real-space approach to chemical characterization of crystal structures. However, applications of this powerful technique have been limited by inefficient X-ray emission and collection, which require long acquisition times. Recently, using a lattice-vector translation method, we have shown that rapid atomic-scale elemental mapping using STEM-EDS can be achieved. This method provides atomic-scale elemental maps averaged over crystal areas of ~few 10 nm2 with the acquisition time of ~2 s or less. Here we report the details of this method, and, in particular, investigate the experimental conditions necessary for achieving it. It shows, that in addition to usual conditions required for atomic-scale imaging, a thin specimen is essential for the technique to be successful. Phenomenological modeling shows that the localization of X-ray signals to atomic columns is a key reason. The effect of specimen thickness on the signal delocalization is studied by multislice image simulations. The results show that the X-ray localization can be achieved by choosing a thin specimen, and the thickness of less than about 22 nm is preferred for SrTiO3 in [001] projection for 200 keV electrons.

The paper intends first to develop a solution mechanism which associates with each economy with a public good a feasible allocation; then, to set up a set of axioms that can make a solution mechanism acceptable in some sense for each agent sharing the cost. It is found finally in the paper that a solution concept, called the Chander dynamic process in which costs are instantaneously shared proportionally to individual marginal rates of substitution, satisfies almost all the required axioms.

Multi-wavelength flares have routinely been observed from the supermassive black hole, Sagittarius A⋆ (Sgr A⋆), at our Galactic center. The nature of these flares remains largely unclear, despite many theoretical models. We study the statistical properties of the Sgr A⋆ X-ray flares and find that they are consistent with the theoretical prediction of the self-organized criticality system with the spatial dimension S = 3. We suggest that the X-ray flares represent plasmoid ejections driven by magnetic reconnection (similar to solar flares) in the accretion flow onto the black hole. Motivated by the statistical results, we further develop a time-dependent magnetohydrodynamic (MHD) model for the multi-band flares from Sgr A⋆ by analogy with models of solar flares/coronal mass ejections (CMEs). We calculate the X-ray, infrared flare light curves, and the spectra, and find that our model can explain the main features of the flares.

We report a simple approach to fabricate high performance energy storage devices based on aqueous inorganic ink comprised of hexagonal MnO2 nanosheets. The MnO2 ink exhibits long term stability. Continuous thin films can be formed on various substrates without using any binder. To obtain a flexible electrode for capacitive energy storage, we printed the MnO2 ink on commercially available A4 paper pre-treated by multi-walled carbon nanotubes. The electrode exhibited a maximum specific capacitance of 90.8 mF/cm2. The electrode could maintain 98.7% capacitance retention for 1,000 cycles at 10 mV/s. The MnO2 ink could be a potential candidate for large-scale production of flexible and printable electronic devices for energy storage and conversion.

A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.

In this work, we investigated the influence of N-polar wet etching on the properties of nitride-based hexagonal pyramids array (HPA) vertical-injection light emitting diodes (V-LEDs). The cathodeluminescence images showed the randomly distribution of hexagonal pyramids with isolated active regions. The transmission electron microscopy images demonstrated the reduced density of threading dislocations. The IQE was estimated by temperature dependence of photoluminescence, which showed 30% increase for HPA V-LEDs compared with broad area (BA) V-LEDs. The improved extraction efficiency was verified by finite difference time domain simulation, which was 20% higher than that of roughened BA V-LEDs. The electrical properties of HPA V-LEDs were measured by conductive atomic force microscopy (CAFM) measurements. HPA V-LEDs exhibited much lower leakage current due to the improved crystal quality.

Photoperiods influence diapause beyond the maternal generation in Cotesia vestalis (Haliday) (Hymenoptera: Braconidae). The sizes, 20-hydroxyecdysone (20E), and juvenile hormone III (JH III) contents in the G1 diapausing prepupae, G0 nondiapausing prepupae, adults, and G1 eggs from C. vestalis cultures reared under three photoperiods (8:16 hours light:dark, 12:12 hours light:dark, and 16:8 hours light:dark) were measured to investigate the hormones’ roles on maternal information transmission and diapause regulation. Results showed that the body size of G1 diapausing prepupae was significantly larger than that of G0 nondiapausing prepupae. The sizes of G0 prepupae, female abdomens, and G1 eggs under eight-hour light were significantly larger than those under 16-hour light. The 20E content in diapausing prepupae was significantly lower than that in nondiapausing prepupae, whereas JH III content did not show significantly difference under the same photoperiod. The 20E content in maternal prepupae, mated females and G1 eggs decreased as the light period was reduced. Juvenile hormone III contents in G0-mated females and G1 eggs (after oviposition) under three photoperiods showed no significant differences. These findings suggest that 20E may play a critical role in diapause regulation of C. vestalis, and be used as a maternal environmental message to be transmitted to the next generation.

The Endangered Mangshan pit viper Protobothrops mangshanensis is endemic to the Nanling Mountain Range of China. It has been targeted for exploitation to satisfy the international pet trade and zoological collections since it was described. Long-term intensive exploitation and habitat destruction have resulted in drastic reductions in wild populations, pushing this rare species towards extinction. Since 1990 only limited investigations have been conducted and the most optimistic estimation of the population size was 300–500 individuals, in 2000. Since then, however, there have been no updates on the population status of this snake in the wild. To provide baseline data for effective conservation of this species we conducted a study of its status and distribution, during 2007–2010. Only eight individuals were found during fieldwork and we documented the illegal harvesting of >30. The total population of the species was estimated to be 462, occupying c. 105 km2 in the Nanling Mountain Range. The black market price of a Mangshan pit viper is currently >USD 1,000 kg−1 and illegal trade has led to over-harvesting, which is the greatest threat to the species. Our study indicates that protected areas cannot effectively protect this pit viper if the trade in this species cannot be controlled. Based on the results of our study we present five recommendations for conservation of the species.

We present astrometric results on two millisecond pulsars, PSR B1257+12 and PSR J1022+1001, as carried out through VLBI. For PSR B1257+12, a model-independent distance of 710−38+43 pc and proper motion of (μα = 46.44 ± 0.08 mas/yr, μδ=−84.87 ± 0.32 mas/yr) were obtained from 5 epochs of VLBA and 4 epochs of EVN observations, spanning about 2 years. The two dimensional proper motion of PSR J1022+1001 (μα~−10.13 mas/yr, μδ~16.89 mas/yr) was also estimated, using 3 epochs of EVN observations. Based on our results, the X-ray efficiency of PSR B1257+12 should be in the same range as other millisecond pulsars, and not as low as previously thought.

The correlation of glutathione S-transferase (GST) M1/T1 genetic polymorphisms with oxidative stress-related chronic diseases was proved recently. The aim of the present study was to investigate the association of GSTM1/T1 genetic polymorphisms with antioxidant biomarkers and consumption of fruits and vegetables (F&V) in healthy subjects. In this study, for conducting a 3 d dietary survey, 190 healthy adults were recruited. After DNA extraction, a multiple PCR method was used for GSTM1/T1 genotyping. A spectrophotometer method was applied for the determination of plasma total antioxidant capacity (T-AOC), vitamin C level and erythrocyte GST enzyme activity. A general linear model was used to compare the mean values of antioxidant parameters for different GSTM1/T1 genotypes and consumption of F&V. Polymorphisms of GSTM1/T1 had no effects on plasma T-AOC and vitamin C levels. Deletion of the GSTM1 gene decreased the erythrocyte GST activity. There was correlation between plasma T-AOC and consumption of F&V in the GSTM1− or GSTT1+ subjects. A similar pattern was evident for erythrocyte GST activity in the GSTM1− subjects. No association was found among consumption of F&V and GSTM1/T1 genotypes and plasma vitamin C level. Different consumption of F&V had no impact on plasma T-AOC and vitamin C levels in the GSTM1−/GSTT1+ or GSTM1−/GSTT1− subjects. The erythrocyte GST activity was more sensitive to consumption of F&V in the individuals with the GSTM1−/GSTT1+ genotype. Association was found among GSTM1/T1 genotypes, antioxidant parameters and consumption of F&V. Large-scale and multiple ethnic studies are needed to further evaluate the relationship.

Currently, there are a variety of techniques to deposit metal thin films ranging from high vacuum techniques such as chemical vapor deposition (CVD) and physical vapor deposition (PVD), through to solution methods like sol-gel. While the vacuum techniques can be limited by size and cost, sol-gel can be limited be the availability of appropriate precursors. All of these techniques have the further limitation that they cannot be used to coat porous materials conformally.

Polymer assisted deposition (PAD) addresses some of the limitations of sol-gel and costs of high vacuum techniques. PAD utilizes an aqueous polymer to bind a metal or metal complex that serves both to encapsulate the metal to prevent chemical reaction and maintain an even distribution of the metal in solution. Another advantage that PAD has is that the same solution can be used as precursors for the growth of metal oxide or reduced metal films. Herein, we report on the utility of PAD in preparing metal oxide films used to conformally coat porous material and reduced metal films.