In this paper, the flexural dynamic characteristics of a laminated composite plate (LCP) with fillers and perforated periodically viscoelastic damping material (VDM) core is researched, which is the ...succession research of refer (Zhou et al. 2015) that could obtain highly effects of vibration energy absorption and dissipation in medium and high frequency, and refer (Zhou et al. 2016), in low frequency. By considering the frequency and temperature properties of VDM, applying the zig-zag theory (ZZT), the equilibrium equations are built by the extended Hamilton’s principle (EHP), and the flexural and shearing deformation compatible equations, and then solved the equations by “rapid” second-order asymptotic expansion method (SAEM) according to the geometry characteristic of the constructed structures, and the opening ratio (OR), filling ratio (FR), the density of embedded material and the height of viscoelastic damping layer which affected the flexural dynamic characteristics of the composite structures are researched thoroughly, and the validity of the calculation is verified by finite element method and the advantages of the composite structures are demonstrated meanwhile.
Laser characteristics of acousto-optic Q-switched operation of 1319 nm/1338 nm dual-wavelength composite Nd:YAG laser were studied. Maximum output power of 5.77 W was achieved in CW operation. Under ...Q-switched operation, the maximum peak power of 3.96 kW and minimum pulse width of 65.6 ns was obtained at repetition frequency of 20 kHz with the duty ratio of 96%. The influence of the duration of the ultrasonic field acted on the Q-switch to the output characteristics of dual-wavelength composite Nd:YAG laser had been reported first time.
Astrometric positions of the Neptunian satellite Triton with a visual magnitude of 13.5 were obtained during three successive oppositions in 2007, 2008 and 2009. A total of 1095 new observed ...positions of Triton were collected during 46 nights of observations, involving eight missions and three telescopes. We compared our observations to the best ephemerides of Triton available now. This comparison has shown that our observations present a high level of accuracy as they provide standard deviations of residuals hardly higher than 50 mas and mean residuals lower than 30 mas, corresponding to about only 500 km in the position of the very distant satellite Triton. Moreover, we have compared most of the different planetary ephemerides of Neptune available now as well as two recent orbit models of Triton. These new comparisons have clearly shown the differences between all of these ephemerides which can be significant and that are presented in this work.
In this study, regenerated cellulose fibers were successfully prepared from cellulose/NaOH/thiourea/urea aqueous solution through an efficient extrusion dissolution method. The microstructure of the ...regenerated cellulose fibers were analysed by using attenuated total reflection infrared (ATR-IR) spectroscopy and the corresponding two-dimensional (2D) correlation spectroscopy. The results showed that the fibers demonstrate a typical crystalline cellulose II and a relatively high crystallinity. Improved crystal structure and tensile strength were obtained in the regenerated cellulose fibers due to improved multi-roller drawing process. The total crystalline index (TCI) and tensile strength of the fibers at different spinning stages were determined in the range of 0.46-0.54 and 1.06-2.30 cN/dtex, respectively. The described cellulose regeneration pathway provided an environmentally friendly and simple method, which could have a significant influence on current cellulose regeneration industries.
Background
Treatment of cephalic arch stenosis (CAS) with standard plain old balloon angioplasty (POBA) in dysfunctional arteriovenous fistulas (AVF), is associated with early re-stenosis and higher ...failure rates compared to other lesions. Paclitaxel-coated balloons (PCB) may improve patency rates. This is a retrospective cohort study. Patients who underwent POBA or PCB for CAS over a 3-year period were included. Outcomes compared were circuit primary patency rates (patency from index procedure to next intervention), circuit primary assisted-patency rates (patency from index procedure to thrombosis), and target lesion (CAS) patency rates (stenosis > 50%) at 3, 6 and 12 months.
Results
Ninety-one patients were included. Sixty-five (71.4%) had POBA, while 26 (28.6%) had PCB angioplasty. There were 62 (68.1%) de-novo lesions. CAS was the only lesion that needed treatment in 24 (26.4%) patients. Circuit primary patency rates for POBA versus PCB groups were 76.2% vs. 60% (
p
= 0.21), 43.5% vs. 36% (
p
= 0.69) and 22% vs. 9.1% (
p
= 0.22) at 3, 6 and 12-months respectively. Circuit assisted-primary patency rates were 93.7% vs. 92% (
p
= 1.00), 87.1% vs. 80% (
p
= 0.51) and 76.3% vs. 81.8% (
p
= 0.77), whilst CAS target lesion intervention-free patency rates were 79.4% vs. 68% (
p
= 0.40), 51.6% vs. 52% (
p
= 1.00) and 33.9% vs. 22.7% (
p
= 0.49) at 3, 6 and 12-months respectively. Estimated mean time to target lesion intervention was 215 ± 183.2 days for POBA and 225 ± 186.6 days for PCB (
p
= 0.20).
Conclusion
Treatment of CAS with PCB did not improve target lesion or circuit patency rates compared to POBA.
Cross-reactivity between antibodies to different human coronaviruses (HCoVs) has not been systematically studied. By use of Western blot analysis, indirect immunofluorescence assay (IFA), and ...enzyme-linked immunosorbent assay (ELISA), antigenic cross-reactivity between severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) and 2 HCoVs (229E and OC43) was demonstrated in immunized animals and human serum. In 5 of 11 and 10 of 11 patients with SARS, paired serum samples showed a ⩾4-fold increase in antibody titers against HCoV-229E and HCoV-OC43, respectively, by IFA. Overall, serum samples from convalescent patients who had SARS had a 1-way cross-reactivity with the 2 known HCoVs. Antigens of SARS-CoV and HCoV-OC43 were more cross-reactive than were those of SARS-CoV and HCoV-229E.
Urban natural surfaces and non-surface human activities are key factors determining the urban heat island (UHI), but their relative importance remains highly controversial and may vary at different ...spatial scales and focal urban systems. However, systematic studies on the scale-dependency system-specificity remain largely lacking. Here, we selected 32 major Chinese cities as cases and used Landsat 8 images to retrieve land surface temperature (LST) and quantify natural surface variables using point of interest (POI) data as a measure of the human activity variable and using multiple regression and relative weight analysis to study the contribution and relative importance of these factors to LST at a range of grain sizes (0.25–5 km) and spatial extents (20–60 km). We revealed that the contributions and relative importance of natural surfaces and human activities are largely scale-dependent and system-specific. Natural surfaces, especially vegetation cover, are often the most important UHI determinants for a majority of scales, but the importance of non-surface human activities is increasingly pronounced at a coarser spatial scale with respect to both grain and spatial extent. The scaling relations of the UHI determinants and their relative importance were mostly linear-like at the city-collective level, but highly diverse across individual cities, so reducing non-surface heat emissions could be the most effective measure in particular cases, especially at relatively large spatial scales. This study advances the understanding of UHI formation mechanisms and highlights the complexity of the scale issue underpinning the UHI effect.
Antibiotics are designed to affect gut microbiota and subsequently gut homeostasis. However, limited information exists about short- and long-term effects of early antibiotic intervention (EAI) on ...gut homeostasis (especially for the small intestine) of pigs following antibiotic withdrawal. We investigated the impact of EAI on specific bacterial communities, microbial metabolites and mucosal immune parameters in the small intestine of later-growth-stage pigs fed with diets differing in CP levels. Eighteen litters of piglets were fed creep feed with or without antibiotics from day 7 to day 42. At day 42, pigs within each group were offered a normal- or low-CP diet. Five pigs per group were slaughtered at days 77 and 120. At day 77, EAI increased Enterobacteriaceae counts in the jejunum and ileum and decreased Bifidobacterium counts in the jejunum and ileum (P < 0.05). Moreover, tryptamine, putrescine, secretory immunoglobulin (Ig) A and IgG concentrations in the ileum and interleukin-10 (IL-10) mRNA and protein levels in the jejunum and ileum were decreased in pigs with EAI (P < 0.05). At day 120, EAI only suppressed Clostridium cluster XIVa counts in the jejunum and ileum (P < 0.05). These results suggest that EAI has a short-term effect on specific bacterial communities, amino acid decarboxylation and mucosal immune parameters in the small intestine (particularly in the ileum). At days 77 and 120, feeding a low-CP diet affected Bifidobacterium, Clostridium cluster IV, Clostridium cluster XIVa and Enterobacteriaceae counts in the jejunum or ileum (P < 0.05). Moreover, feeding a low-CP diet increased the concentrations of Igs in the jejunum and decreased pro-inflammatory cytokines levels in the jejunum and ileum (P < 0.05). At day 120, feeding a low-CP diet increased short-chain fatty acid concentrations, reduced ammonia and spermidine concentrations and up-regulated genes related to barrier function in the jejunum and ileum (P < 0.05). These results suggest that feeding a low-CP diet changes specific bacterial communities and intestinal metabolite concentrations and modifies mucosal immune parameters. These findings contribute to our understanding on the duration of the impact of EAI on gut homeostasis and may provide basis data for nutritional modification in young pigs after antibiotic treatment.
We demonstrate molecule‐specific third‐harmonic‐generation (THG) microscopy by using silver nanoparticles as THG contrast agents. Through matching surface plasmon wavelength to THG wavelength, strong ...contrast can be provided by silver nanoparticles under THG microscopy. By conjugating anti‐her2 antibodies with silver nanoparticles, the expression of the Her2/neu oncogene in the cancer cell membranes is successfully imaged under THG modality for the first time.
For physical surface modification of a complex workpiece, the incoming particles are difficult to arrive at the inclined surface of the complex workpiece due to self-shadowing effect. This will ...result in the non-uniformity distribution of structure and properties of the films on different surfaces of the complex workpiece. In order to mitigate the self-shadowing effect and improve the uniformities of film structure and properties, high power pulsed magnetron sputtering (HPPMS) was used to fabricate TiN films on 316L stainless steel substrate with different inclination angles. During deposition, the electrical characteristic of HPPMS was recorded by an oscilloscope, and the plasma component was diagnosed by optical emission spectroscopy. The structure, mechanical and corrosion properties of the TiN films deposited on substrate with different inclination angles by DC magnetron sputtering (DCMS) and HPPMS also were studied respectively. Compared with DCMS, the results showed that high ion/atom ratio and large ion flux in HPPMS led to stronger ion bombardment and adatom mobility, which caused densification of the TiN films. The uniformities of hardness and corrosion resistance of the TiN films deposited on the substrate with different inclination angles were improved by HPPMS. And for HPPMS, the longer pulses at same duty cycle could efficiently mitigate the self-shadowing effect and improve the hardness and corrosion resistance of the TiN-coated stainless steel.
•The TiN films deposited at different inclination angles by DCMS show bad uniformity.•The uniformities of film hardness and corrosion resistance can be improved by HPPMS.•The longer pulses are helpful to mitigate the self-shadowing effect at same duty cycle for HPPMS.
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