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Impulse pressuring diffusion bonding(IPDB) and constant pressuring diffusion bonding(CPDB) of TiC cermet to 304 stainless steel(304SS) using Ti/Nb interlayer was carried out at 890℃ under a impulse pressuring of 2-10MPa and a constant pressuring of 10MPa within a duration of only 4-12min, and a robust metallurgical bonding was achieved. Microstructure characterization and shear performance of the IPDB and CPDB joints were analyzed by SEM, EDS, XRD and shearing test. The results show that the interface phases in those two kinds of joints are similar, which are mainly σ phase,(β-Ti, Nb) and α+β-Ti solid solution. When the joint is bonded for 10min, shear strength of TiC/304SS CPDB joints is 55.6MPa, while the shear strength of IPDB joints reaches 110MPa. The fracture of CPDB joints is TiC cermet fracture, while that of IPDB joints is mixed fracture by alternated between TiC cermet and reaction layer.

The thermal-electric finite element simulation model of carbon fiber reinforced plastic(CFRP) damage caused by lightning strike was established. The superimposed temperature was treated as the internal injury. The accuracy and effectiveness of coupled thermal-electric simulation method were verified by comparing with the experimental results. The regression analysis was taken into consideration to give a quantitative analysis of lightning parameters and CFRP lightning damage, and the relevant curves were drawn. The results show that action integral is a key factor in determining the injury status of CFRP laminates. Fiber damage area and delamination area have a linear relationship with the action integral. And resin damage area and damage thickness have a logarithmic relation with the action integral.

With the development of image processing technology and the improvement of unmanned aerial vehicle (UAV) manufacture, it has been becoming a hot research topic to inspect the transmission line's failure. Here, a method of locating the area of insulator strings in the aerial image captured by UAV system is been introduced. At first, the aerial image is converted to HSV colour space model, and the components of H and S are filtered to segment the insulator strings and background areas. Considering some background areas have the similar colour with the insulator string, the result of segmentation will contain some background areas. Then, the image of result is divided into small pieces with non-overlapping windows. The information of texture on each window is used to remove the remaining background area. The outline of the insulator strings in the image can be obtained. It is easily to detect the edge of the insulator string and locate the area of the insulator string using the outline image. At last, some insulator string images have been used to illustrate the processing of the method. Compared with the method using RGB colour space model, the results of method here is effective and reliable.

BackgroundMetal-oxide interface plays critical roles in promoting the catalytic activities of metal catalysts in a vast diversity of reactions. Maximizing this interfacial interaction so as to optimize the catalytic performance is an active subject of research that is worthy of intensive exploration.PurposeThis study aims to develop new Pt-group catalysts that are highly active towards cryogenic CO catalytic oxidation, and explore effective strategies to engineer metal-oxide (hydroxide) interfaces to weaken the adsorption of CO and to enhance the adsorption/activation of O2.MethodsSupported ultrasmall Pt nanoclusters (Ptnc-FeOx/SiO2) of (1.4±0.2) nm were synthesized using deposition-precipitation with urea (DPU). The catalytic performance towards CO oxidation was examined by using a fixed-bed U-shape flow quartz reactor. Extended X-ray absorption fine structure (EXAFS), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray spectroscopy (EDX) techniques were combined to study the Ptnc-FeOx interfacial interaction.ResultsThe Ptnc-FeOx/SiO2 catalyst shows superior catalytic performance than Pt/SiO2 towards the CO oxidation reaction. Kinetics tests show that both the apparent activation energy and turnover frequency of Ptnc-FeOx/SiO2 are greatly enhanced as compared with Pt/SiO2 (19 kJ·mol-1 vs. 64 kJ·mol-1; 0.044 s-1 vs. 0.002 s-1 at 37 °C).ConclusionThe charge transfer from Fe to Pt results in the downshifted d-band center of Pt and reduces the CO adsorption strength, and hence, playing important roles in promoting the catalytic activity of Pt catalysts.

INTRODUCTION: Allogeneic hematopoietic cell transplantation (alloHCT) is increasingly offered to older adults, and its potential impact on cognition in this population is understudied. This work aims to evaluate the ability of cancer-specific geriatric assessments (cGA) and a global frailty index based on accumulation of deficits identified in the cGA to predict the risk of cognitive decline after alloHCT in older adults. MATERIALS AND METHODS: AlloHCT recipients aged 50 years or older completed a cGA, including a cognitive evaluation by the Blessed Orientation Memory Concentration (BOMC) test, at baseline prior to alloHCT and then at 3, 6, and 12 months after transplant. Baseline frailty was assessed using a deficit accumulation frailty index (DAFI) calculated from the cGA. A multinomial logit model was used to examine the association between predictors (individual cGA measures, DAFI) and the following three outcomes: alive with stable or improved cognition, alive with cognitive decline, and deceased. In post-hoc analyses, analysis of variance was used to compare BOMC scores at baseline, 3, 6, and 12 months across frailty categories. RESULTS: In total, 148 participants were included, with a median age of 62 (range 50-76). At baseline, 12% had cognitive impairment; at one year, 29% of survivors had improved BOMC scores, 33% had stable BOMC, and 37% had worse BOMC. Prior to transplant, 25% were pre-frail and 11% were frail. Individual baseline cGA measures were not associated with cognitive change at one year as assessed by BOMC. Adjusting for age, sex, and education, those who were frail at baseline were 7.4 times as likely to develop cognitive decline at one year than those who were non-frail, although this finding did not reach statistical significance (95% confidence interval [CI] 0.74-73.8, p = 0.09). The probability of being alive with stable/improved cognition at 12 months for the non-frail, pre-frail, and frail groups was 43%, 34%, and 8%, respectively. DISCUSSION: Baseline geriatric measures and frailty were not significantly associated with cognitive change as assessed by BOMC in adults aged 50 or older after alloHCT. However, the study was underpowered to detect clinically meaningful differences, and future work to elucidate potential associations between frailty and cognitive outcomes is warranted.

Ming Dynasty is a key transitional period in China’s maritime history. It marks the shift from outward expansion to passive defense, whereas underground marine trades were rampant and China had to face the rising Western powers. It deserves to examine Ming’s maritime management by different perspectives including the coastal islands. This research focuses on Veritable Records of the Ming(明實錄) and explores key terms such as ‘island’(島) and ‘isle’(嶼) via the approach of ‘Digital Humanities’ to sum up the main issues of islands governing in early Ming Dynasty: 1. To subjugate political rivals on the sea and to defeat remnant Mongolian militaries. 2. To surrender rebels and appease refugees on the coastal islands. 3. To suppress and defend against Japanese pirates. 4. Diplomatic relations with neighboring countries. These issues reflected that Chinese dynastic regime transition from Yuan to Ming not only drastically altered the order of the East Asia seas after 14th c., but was also the key factor for the island governing policies in the early Ming period. This article investigates the issues of islands governing to discuss how the internal and external situation and the characteristic oceanic consciousness influenced the marine affair policy decision in early Ming Dynasty.

Based on an analysis of the precision and preparation technology of an optical texture film with a triangular pyramid texture, the technical requirements of the original mold were determined, and precision shaping planning technology was adopted to process the original mold. The shape error of the optical texture mold of the triangular pyramid was assessed by defining the area ratio of the retro-reflection. The influence of the tool nose radius and exit burr on the area ratio of the retro-reflection were analyzed. By optimizing the cutting tools, cutting materials and cutting boundaries, a five-axis ultra-precision machining system was used to plan the triangular pyramid structure with a base length of 115 µm and an included angle between two sides of 70.5°. The experimental results indicate that the dimension error of the triangular pyramid element is less than 1 µm, the angle error of the included angle between two sides is less than 0.05°, and the average roughness of the side of the triangular pyramid can reach 9.2 nm, which satisfies the processing quality requirements of the triangular pyramid texture mold.

Enterocytozoon bieneusi is an intestinal pathogen that infects a wide range of species, including humans. Cattle constitute an important host for E. bieneusi; however, there is a scarcity of information on the prevalence and genotyping of E. bieneusi in cattle in the Hainan Province of China. In this study, PCR analysis of 314 fecal samples from cattle in six cities of Hainan was performed for genotype identification. The average prevalence of E. bieneusi in these animals was 9.9% (31/314), and ranged from 0.0% (0/12) to 20.5% (8/39). Five known genotypes – EbpC (n = 14), BEB4 (n = 12), J (n = 2), I (n = 1), and CHG5 (n = 1) – and a novel genotype: HNC-I (n = 1) – were identified. Genotypes EbpC and HNC-I were placed in zoonotic Group 1, and the remaining four genotypes (BEB4, J, I, and CHG5) were placed in Group 2. Since 93.5% of the genotypes found in the cattle (29/31) (EbpC, BEB4, J, and I) have previously been found in humans, these genotypes are probably involved in the transmission of microsporidiosis to humans.

Rigid flow deflectors are usually used on water flow beds to protect engineering structures such as breakwater in coasts and to regulate flow routes in open channels. To reduce its side-effects, i.e., local scour at the toe of deflectors, a flexible flow deflector is proposed, and the corresponding local scour was investigated in this study. A flume experiment was conducted to investigate local scour. To show the advantage of flexible deflectors, a control experimental test was also conducted using a traditional rigid deflector under the same blockage area configuration and the same flow conditions. The flow field near the flexible deflector was also measured to reveal the local flow field. The results show that the bed-scour develops near the toe edges of both flexible and rigid deflectors, but the maximum and averaged scour depths for the flexible deflector are smaller. This advantage of flexible deflector in scour depth is mainly caused by its prone posture, which induces the upward stretching and enlarging horizontally rotating vortex and the upward shifted vertically rotating vortex. The former dissipates more turbulent energy and the latter results in smaller bed shear stress, which lead to smaller scour depth directly. In addition, the up- and down-swaying movement of the flexible deflector can also assistant to dissipate more turbulent energy, thereby damping the intense of the horseshoe vortices and thus weakening scour depth as well. The results of this study provide an elementary understanding on the mechanisms of a flexible flow structure and an alternative deflector-device to reduce scour depth.

A simple, rapid and specific ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed for the analysis of 29 bioactive components (10 phenolic acids, 16 flavonoids, and three iridoid glycosides) in Yinhua Kanggan tablet (YHKGT), a herbal prescription used for treating upper respiratory infections, fevers, coughs and pharyngalgia. The separation was successfully achieved using a Waters Cortecs UPLC C18 column (50 × 2.1 mm, 1.6 μm) and gradient elution with water-0.1% formic acid and acetonitrile. Polarity switching mode was used in the optimization of multiple reaction monitoring conditions. The analytical method was validated for linearity, precision and accuracy. Calibration curves for the 29 marker compounds showed good linear regression (r > 0.9982). The limits of detection (LOD) and limits of quantification (LOQ) for the 29 analytes were in the range of 0.03–4.99 ng/mL and 0.16–14.87 ng/mL, respectively. The relative standard deviation (RSD) values of intra-day precision, inter-day precision, repeatability, and stability were less than 2.79%, 4.87%, 4.18% and 4.71%, respectively. The recoveries of the 29 marker compounds were in the range of 94.67%–104.78% (RSD ≤ 4.72%). These results have shown that this developed method was efficient for the quality evaluation of YHKGT.

Background: Human menopausal gonadotropin (hMG) has contributed many improvements to human assisted reproduction. However, effects of hMG on oocyte development and clinical results remain controversial. Objective: This study was conducted to investigate the effects of hMG on the zona pellucida of oocytes, as well as clinical results in superovulation treatment. Materials and Methods: This retrospective study was performed with 150 cycles of long-protocol treatment using recombinant follicle-stimulating hormone (r-FSH) with or without hMG. The number of retrieved oocytes, fertilization rate, implantation rate, pregnancy rate, and birefringence and thickness of the zona pellucida of oocytes were investigated. Results: No significant differences were existed in r-FSH +hMG, and r-FSH groups in the number of retrieved oocytes (11.99±0.75 vs. 13.9±0.73, p=0.06), maturation rate (84.76% vs. 83.32%, p=0.42), pregnancy rate (37.31% vs. 37.66%, p=0.96), and embryo implantation rate (28.97% vs. 23.26%, p=0.30). However, fertilization rate (82.95% vs. 78.75%; p=0.02) was different. Zona pellucida birefringence was lower in the r-FSH +hMG group than in the r-FSH group (6.70±0.50 vs. 7.04±0.31; p=0.53). Thickness values of the metaphase-II zona pellucida of the r-FSH +hMG group on the first (19.20±0.14 vs. 18.75±0.10; p=0.01) and second (18.69±0.12 vs. 18.17±0.14; p=0.00) days of insemination were both higher than those of the r-FSH group. Conclusion: hMG positively influenced the improvement of oocyte fertilization, as well as the birefringence and thickness of zona pellucida.

BackgroundDengue virus outbreaks are increasing in number and severity worldwide. Viral transmission is assumed to require a minimum time period of viral replication within the mosquito midgut. It is unknown if alternative transmission periods not requiring replication are possible.MethodsWe used a mouse model of dengue virus transmission to investigate the potential of mechanical transmission of dengue virus. We investigated minimal viral titres necessary for development of symptoms in bitten mice and used resulting parameters to inform a new model of dengue virus transmission within a susceptible population.FindingsNaïve mice bitten by mosquitoes immediately after they took partial blood meals from dengue infected mice showed symptoms of dengue virus, followed by mortality. Incorporation of mechanical transmission into mathematical models of dengue virus transmission suggest that this supplemental transmission route could result in larger outbreaks which peak sooner.InterpretationThe potential of dengue transmission routes independent of midgut viral replication has implications for vector control strategies that target mosquito lifespan and suggest the possibility of similar mechanical transmission routes in other disease-carrying mosquitoes.FundingThis study was funded by grants from the National Health Research Institutes, Taiwan (04D2-MMMOST02), the Human Frontier Science Program (RGP0033/2021), the National Institutes of Health (1R01AI143698-01A1, R01AI151004 and DP2AI152071) and the Ministry of Science and Technology, Taiwan (MOST104-2321-B-400-016).