This study has explored perceived crowding of an underwater environment. Two dimensions were assessed: the number of divers seen and the proximity of divers to each other. Data were obtained from a ...survey of 216 divers who undertook diving in Hong Kong during 2013–14. Photographs depicting four levels of crowding (number of divers) and four levels of diver proximity in different combinations were shown to the respondents for assessing acceptability. Between the two variables, the “number of divers” was the most influential factor to divers' perceived crowding. Divers' begin to feel unacceptably crowded if 7∼8 divers are visible to them at one time. Based on this, it is likely that the usage of Hong Kong diving sites has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Hong Kong diving sites are also discussed in the paper.
•Demonstrated the rapid appraisal of the social carrying capacity of a diving site.•“Number of divers” was the most influential factor for divers' perceived crowding.•Divers begin to feel unacceptably crowded if 7 to 8 divers are visible to them at one time.•Hong Kong diving sites may already exceeded its social carrying capacity.
(Ba1-xCax)(Ti0.90Sn0.10)O3-0.08Dy2O3 (x = 0.02–0.10) ceramics. Optimized piezoelectric properties: d33 = 675 pC/N, Kp = 55%.
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•MPB exists in the BCTSD ceramics with ...x = 0.06–0.10.•BCTSD ceramics exhibit typical diffuse phase transition behavior, which is not sensitive to the amount of Ca2+ ions.•Remarkable improvement on piezoelectric properties (d33 = 675 pC/N, kp = 55%) were achieved at x = 0.06.
(Ba1-xCax)(Ti0.90Sn0.10)O3-0.08Dy2O3 ceramics (BCTSD-x, x = 0.02–0.10) were fabricated by conventional solid state sintering method. The effect of Ca2+ ions addition on the phase structure, microstructure, and electric properties of ceramics were studied. X-ray diffraction analysis reveals the replacement of Ba2+ ions in the perovskite structure by Ca2+ ions. Rhombohedral phase and tetragonal phase coexist in the composition with x = 0.06–0.10. Both d33 and Kp of the ceramics increase with increasing Ca concentration, and attain maximum values of 675 pC/N and 55.0%, respectively, for x = 0.06. All the ceramics present typical diffuse phase transition behavior, and the feature is not sensitive to the amount of Ca2+ ions.
The opposite effects of chemotherapy, which enhance the malignancy of treated cancers such as hepatocellular carcinoma (HCC), are not well understood. We investigated this phenomenon and ...corresponding mechanisms to develop a novel approach for improving chemotherapy efficacy in HCC.
Human hepatocellular carcinoma cell lines HepG2 (with low metastatic potential) and MHCC97L (with moderate metastatic potential) were used for the in vitro study. An orthotopic nude mouse model of human HCC was developed using MHCC97L cells. We then assessed the metastatic potential of surviving tumor cells after in vitro and in vivo oxaliplatin treatment. The molecular changes in surviving tumor cells were evaluated by western blot, immunofluorescence, and immunohistochemistry. The Chinese herbal extract Songyou Yin (composed of five herbs) was investigated in vivo to explore its effect on the metastatic potential of oxaliplatin-treated cancer cells.
MHCC97L and HepG2 cells surviving oxaliplatin treatment showed enhanced migration and invasion in vitro. Residual HCC after in vivo oxaliplatin treatment demonstrated significantly increased metastasis to the lung (10/12 vs. 3/12) when re-inoculated into the livers of new recipient nude mice. Molecular changes consistent with epithelial-mesenchymal transition (EMT) were observed in oxaliplatin-treated tumor tissues and verified by in vitro experiments. The Chinese herbal extract Songyou Yin (4.2 and 8.4 g/kg) attenuated EMT and inhibited the enhanced metastatic potential of residual HCC in nude mice (6/15 vs. 13/15 and 3/15 vs. 13/15, respectively).
The surviving HCC after oxaliplatin treatment underwent EMT and demonstrated increased metastatic potential. Attenuation of EMT by Songyou Yin may improve the efficacy of chemotherapy in HCC.
Purpose To evaluate the prognostic value of tumor-associated macrophages (TAM), individually or synergistically with CD45RO + memory T cells (TM), in hepatocellular carcinoma (HCC) patients following ...resection. Methods The infiltration of TAM and TM was assessed by immunohistochemistry in tissue microarray containing 302 HCC specimens. Correlations between TAM/TM infiltration and clinicopathologic features, disease-free survival (DFS) and overall survival (OS) were statistically analyzed. Results High TAM infiltration was associated with both improved DFS (P = 0.0021) and OS (P = 0.0481). Multivariate analysis identified TAM infiltration as independent prognostic factor for DFS (P = 0.004) and OS (P = 0.049). A second analysis clarified the synergistic effect of TAM&TM infiltration for DFS (P = 0.004) and OS (P = 0.040). Conclusions Both TAM infiltration alone and concomitant infiltration of TAM&TM are associated with improved DFS/OS, suggesting that TAM could protect HCC patients from recurrence/metastasis and prolong survival by distinct mechanisms.
Several studies have reported an association between vascular endothelial growth factor (VEGF) gene polymorphisms rs2010963, rs3025039 and rs699947 and renal cell carcinoma (RCC). However, the ...results remain inconclusive and controversial. We therefore conducted a meta-analysis to evaluate this association. Electronic databases were searched for relevant case-control studies up to November 2016. RevMan 5.2 software and STATA version 12.0 were used for statistical analysis in our meta-analysis. Heterogeneity was assessed using the I2 value. Nine eligible studies were retrieved for detailed evaluation. The pooled estimates indicated that the GG genotype of VEGF rs2010963 polymorphism significantly decreased RCC risk GG vs. GC+CC; GG vs. GC. There was also a significant association between VEGF rs3025039 polymorphism and RCC susceptibility CC+CT vs. TT; CC vs. TT. Furthermore, a significant association between VEGF rs699947 polymorphism and RCC susceptibility was detected A vs. C; AA+AC vs. CC; AA vs. AC+CC; AA vs. CC; AA vs. AC; AC vs. CC. Subgroup analysis revealed that these associations held true especially for Asians. Our meta-analysis suggested that there may be a relationship between the VEGF rs2010963, rs3025039 and rs699947 polymorphisms and RCC susceptibility.
Some fungi engage symbiosis with bacteria, which can effectively promote the metabolism and growth of fungi. The diversity and community structure of bacteria can reflect the growth and substrate ...utilization of fungi. In this study, we analyzed the effects of different sawdust dosages on the community structure and diversity of bacteria associated with the hyphae of
using high-throughput sequencing technology (HST) based on PCR-amplified 16S rRNA V3-V4 fragments. The results showed that the high-quality sequences from five groups of mycelia samples were clustered into 25 phyla, 52 classes, 114 orders, 199 families, and 406 genera. Proteobacteria (35.0%-85.9%) and Firmicutes (6.5%-38.4%) were the most abundant bacterial phyla, while
(14.8%-71.6%) and
(1.7%-22.3%) were the dominant symbiotic genera. Compared with the mycelia grown on the complete culture medium, sawdust addition could increase the diversity of bacteria coexisting with
mycelia, and change the community structure of 10 dominant phyla and 9 domina
In recent years, the gaze estimation system, as a new type of human-computer interaction technology, has received extensive attention. The gaze estimation model is one of the main research contents ...of the system. The quality of the model will directly affect the accuracy of the entire gaze estimation system. To achieve higher accuracy even with simple devices, this paper proposes an improved mapping equation model based on homography transformation. In the process of experiment, the model mainly uses the “Zhang Zhengyou calibration method” to obtain the internal and external parameters of the camera to correct the distortion of the camera, and uses the LM(Levenberg-Marquardt) algorithm to solve the unknown parameters contained in the mapping equation. After all the parameters of the equation are determined, the gaze point is calculated. Different comparative experiments are designed to verify the experimental accuracy and fitting effect of this mapping equation. The results show that the method can achieve high experimental accuracy, and the basic accuracy is kept within 0.6∘. The overall trend shows that the mapping method based on homography transformation has higher experimental accuracy, better fitting effect and stronger stability.
A reduction in cochlear blood flow plays an essential role in noise-induced hearing loss (NIHL). The timely regulation of cochlear perfusion determines the progression and prognosis of NIHL. Hydrogen ...sulfide (H(2)S) has attracted increasing interest as a vasodilator in cardiovascular systems. This study identified the role of H(2)S in cochlear blood flow regulation and noise protection.
The gene and protein expression of the H(2)S synthetase cystathionine-γ-lyase (CSE) in the rat cochlea was examined using immunofluorescence and real-time PCR. Cochlear CSE mRNA levels varied according to the duration of noise exposure. A chronic intracochlear infusion model was built and artificial perilymph (AP), NaHS or DL-propargylglycine (PPG) were locally administered. Local sodium hydrosulfide (NaHS) significantly increased cochlear perfusion post-noise exposure. Cochlear morphological damage and hearing loss were alleviated in the NaHS group as measured by conventional auditory brainstem response (ABR), cochlear scanning electron microscope (SEM) and outer hair cell (OHC) count. The highest percentage of OHC loss occurred in the PPG group.
Our results suggest that H(2)S plays an important role in the regulation of cochlear blood flow and the protection against noise. Further studies may identify a new preventive and therapeutic perspective on NIHL and other blood supply-related inner ear diseases.
Plasma nitriding is a widely used technology to enhance the surface performance and extend the service life of alloy parts. The current research mainly focuses on the influences of time, temperature, ...gas type and pressure parameters on nitriding behavior, while fewer studies have been conducted on the electric potential. This paper mainly reports the effect of the electric potential on nitriding behavior. Test conditions were set using cathodic, anodic and floating potentials in a plasma nitriding furnace. 2Cr13 stainless steel was nitrided at 450 °C for 5 h in an NH
3
atmosphere. The experimental results show that the nitriding treatment can be well performed under the different electric potentials, but differences exist in microstructures, morphologies and performance results of the modified layers. The thickness and hardness values of the nitrided layer are ranked as follows: cathodic > anodic > floating potential. The anodic nitrided surface has an obvious particle deposition layer composed of nitrides and oxides. Electrochemical and tribological experiments show that the corrosion resistance and wear resistance were significantly improved after a nitriding treatment using the three electric potentials. Moreover, the floating nitriding treatment resulted in the best tribological performance and corrosion resistance.
Sulfur mustard (HD) poses a serious threat to society due to its dramatic toxicity, and thus, exploring efficient catalysts for the degradation of HD is of great significance from the perspective of ...national health and social security. Photocatalytic oxidation of HD is considered an effective detoxification method due to its mild reaction conditions and high selectivity. The emerging photocatalyst of covalent organic frameworks (COFs) with tunable structure and unique optical properties has attracted wide interest due to their great potential in HD decontamination. Herein, a photosensitive COF (TAPP–TFPT) was constructed by the Schiff base reaction, and then, a facile postmodification strategy was proposed to deposit silver nanoparticles on TAPP–TFPT (Ag@TAPP–TFPT) to enhance the photocatalytic degrading performance on HD simulants. Under the irradiation of visible light, both superoxide ion (O2 •–) and singlet oxygen (1O2) were produced by Ag@TAPP–TFPT, and then, HD simulants can be selectively degraded into nontoxic bis(2-chloroethyl) sulfoxide with a half-life (t 1/2) of 6.5 min and excellent reusability. This work demonstrates that postmodification of COFs offers a promising direction for the rational design of photocatalysts with good selectivity and high efficiency toward degradation of chemical warfare agents.
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