In order to achieve the preferential selection of pavement waterproofing layer materials, so that the waterproofing layer material selection is more scientific and objective, eliminating the impact ...of subjective factors, this paper uses hierarchical analysis to build a hierarchical evaluation model of pavement waterproofing layer. Based on the literature review method, a two-tier evaluation index of the layered evaluation model of pavement waterproofing layer materials was constructed, mainly three first-tier indexes of performance assessment, service life assessment, and cost assessment, under which the second-tier indexes of waterproofing performance, durability, weather resistance, impermeability, crack resistance, thermal stability, aging resistance, low temperature crack resistance, fatigue resistance, material cost, construction cost, and maintenance cost were established. And through the hierarchical analysis method of calculation, test the consistency by deriving the weight of each indicator, where the most important first layer of indicators for performance, the weight of 0.5390, the second layer of indicators is more important for waterproof performance (0.5303), thermal stability (0.3550), low-temperature crack resistance (0.3550), material cost (0.6333). The study provides a scientific and objective evaluation model for the preferential selection of pavement waterproofing layer materials.
Epidemiological evidence of short-term fine particulate matter (PM2.5) exposure on blood pressure (BP), heart rate (HR) and related inflammation biomarkers has been inconsistent. We aimed to explore ...the acute effect of PM2.5 on BP, HR and the mediation effect of related inflammation biomarkers. A total of 32 healthy college students were recruited to perform 4 h of exposure at two sites with different PM2.5 concentrations in Wuhan between May 2019 and June 2019. The individual levels of PM2.5 concentration, BP and HR were measured hourly for each participant. Blood was drawn from each participant after each visit and we measured the levels of inflammation markers, including serum high-sensitivity C-reactive protein and plasma fibrinogen. Linear mixed-effect models were to explore the acute effect of PM2.5 exposure on BP, HR, and related inflammation biomarkers. In addition, we evaluated related inflammation biomarkers as the mediator in the association of PM2.5 and cardiovascular health indicators. The results showed that a 10 μg/m3 increment in PM2.5 concentration was associated with an increase of 0.84 (95% CI: 0.54, 1.15) beats/min (bpm) in HR and a 3.52% (95% CI: 1.60%, 5.48%) increase in fibrinogen. The lag effect model showed that the strongest effect on HR was observed at lag 3 h of PM2.5 exposure 1.96 bpm (95% CI: 1.19, 2.75), but for fibrinogen, delayed exposure attenuated the association. Increased fibrinogen levels may account for 39.07% (P = 0.44) of the elevated HR by PM2.5. Null association was observed when it comes to short-term PM2.5 exposure and BP. Short-term exposure to PM2.5 was associated with elevated HR and increased fibrinogen levels. But our finding was not enough to suggest that exposure to PM2.5 might induce adverse cardiovascular effects by the pathway of inflammation.
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•PM2.5 exposure is a risk factor for cardiovascular diseases.•Personal exposure to PM2.5 for a short term can elevate heart rate and fibrinogen levels.•The role of inflammation in PM2.5-induced cardiovascular effects was explored.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Particulate matter pollution could increase the risk of kidney disease, while evidence for ozone exposure is less well-established. Here, we aimed to evaluate the effect of ozone pollution on renal ...function and explore mechanisms. We first conducted a cross-sectional study based on Wuhan Chronic Disease Cohort Study baseline information. We recruited 2699 eligible participants, estimated their residential ozone concentrations, collected fasting peripheral blood samples for biochemical analysis and calculated the estimated glomerular filtration rate (eGFR). The linear regression model was applied to evaluate the long-term association between ozone pollution and eGFR. Then, we recruited another 70 volunteers as a panel with 8 rounds follow-up visits. We calculated the eGFR and measured fasting blood glucose and lipid levels. The linear mixed-effect model along with mediation analysis were performed to confirm the short-term association and explore potential mechanisms, respectively. For the long-term association, a 10.95 μg/m
increment of 3-year ozone exposure was associated with 2.96 mL/min/1.73 m
decrease in eGFR (95%CI: -4.85, -1.06). Furthermore, the drinkers exhibited a pronounced declination of eGFR (-7.46 mL/min/1.73 m
, 95%CI: -11.84, -3.08) compared to non-drinkers in relation to ozone exposure. Additionally, a 19.02 μg/m
increase in 3-day ozone concentrations was related to 2.51 mL/min/1.73 m
decrease in eGFR (95%CI: -3.78, -1.26). Hyperglycemia and insulin resistance mediated 12.2% and 16.5% of the aforementioned association, respectively. Our findings indicated that higher ozone pollution could affect renal function, and the hyperglycemia and insulin resistance linked to ozone might be the underlying mechanisms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives
Tongue squamous cell carcinoma (TSCC) is the most frequent type of oral malignancy. Increasing evidence has shown that miRNAs play key roles in many biological processes such as cell ...development, invasion, proliferation, differentiation, metabolism, apoptosis and migration.
Materials and methods
qRT‐PCR analysis was performed to measure miR‐137 expression. CCK‐8 analysis, cell colony formation, wound‐healing analysis and invasion were performed to detect resultant cell functions. The direct target of miR‐137 was labelled and measured by luciferase assay and Western blotting.
Results
We demonstrated that expression of miR‐137 was downregulated in TSCC tissues compared to matched normal ones. miR‐137 expression was downregulated in TSCC lines (SCC4, SCC1, UM1 and Cal27) compared to the immortalized NOK16B cell line and normal oral keratinocytes in culture (NHOK). In addition, we have shown that miR‐137 expression was epigenetically regulated in TSCCs. Overexpression of miR‐137 suppressed TSCC proliferation and colony formation. Ectopic expression of miR‐137 promoted expression of the epithelial biomarker, E‐cadherin, and inhibited the mesenchymal biomarker, N‐cadherin, as well as vimentin and Snail expression, indicating that miR‐137 suppressed TSCC epithelial‐mesenchymal transition (EMT). We also showed that ectopic expression of miR‐137 inhibited TSCC invasion and migration. In addition, we identified SP1 as a direct target gene of miR‐137 in SCC1 cells. SP1 overexpression rescued inhibitory effects exerted by miR‐137 on cell proliferation and EMT.
Conclusions
These results indicate that miR‐137 acted as a tumour suppressor in TSCC by targeting SP1.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Surface topography is increasingly being recognized as an important factor to control the response of cells and tissues to biomaterials. In the current study, the aim was to obtain deeper ...understanding of the effect of microgrooves on shape and orientation of osteoblast-like cells and to relate this effect to their proliferation and osteogenic differentiation. To this end, two microgrooved polystyrene (PS) substrates, differing in the width of the grooves (about 2 μm and 4 μm) and distance between individual grooves (about 6 μm and 11 μm, respectively) were fabricated using a combination of photolithography and hot embossing. MG-63 human osteosarcoma cells were cultured on these microgrooved surfaces, with unpatterned hot-embossed PS substrate as a control. Scanning electron- and fluorescence microscopy analyses showed that on patterned surfaces, the cells aligned along the microgrooves. The cells cultured on 4 μm-grooves / 11 μm-ridges surface showed a more pronounced alignment and a somewhat smaller cell area and cell perimeter as compared to cells cultured on surface with 2 μm-grooves / 6 μm-ridges or unpatterned PS. PrestoBlue analysis and quantification of DNA amounts suggested that microgrooves used in this experiment did not have a strong effect on cell metabolic activity or proliferation. However, cell differentiation towards the osteogenic lineage was significantly enhanced when MG-63 cells were cultured on the 2/6 substrate, as compared to the 4/11 substrate or unpatterned PS. This effect on osteogenic differentiation may be related to differences in cell spreading between the substrates.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The first fractured shale gas well of China was constructed in 2010. After 10 years of development, China has become the second country that possesses the core technology of shale gas development ...around the world, realized the shale gas fracturing techniques from zero to one and from lagging to partially leading, and constructed the fracturing theory and technology system suitable for middle–shallow marine shale gas exploitation. In order to provide beneficial guidance for the efficient exploitation of shale gas in China in the future, this paper comprehensively reviews development history and status of domestic fundamental theories, optimized design methods, fluid systems, tools and technologies of shale gas fracturing and summarizes the research results in fundamental theories and optimized design methods, such as fracturing sweet-spot cognition, fracture network propagation simulation and control, rock hydration and flowback control, and SRV (stimulated reservoir volume) evaluation and characterization. The development and application of slick-water fracturing fluid system and new fracturing fluid with little or no water is discussed. The development and independent research & development level of multi-stage fracturing tools are evaluated, including drillable composite plug, soluble plug, large-diameter plug and casing cementing sleeve. The implementation situations of field technologies and processes are illustrated, including the early conventional multi-stage multi-cluster fracturing and the current “dense cluster” fracturing and temporary plugging fracturing. Based on this, the current challenges to domestic shale gas fracturing technologies are analyzed systematically, and the development direction of related technologies is forecast. In conclusion, it is necessary for China to continuously research the fracturing theories, technologies and methods suitable for domestic deep and ultra-deep marine shale gas, terrestrial shale gas and transitional shale gas to facilitate the future efficient development of shale gas in China.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper documents our comparative study on the community environments of giant pandas Ailuropoda melanoleuca between Wolong National Nature Reserve (Wolong NNR), Tangjiahe NNR, and Heizhugou NNR ...in Sichuan, China using infrared camera data collected from 2017 to 2021, in an attempt to explore the ecological relations of the giant panda with other animals. Results showed that the giant panda belonged to the species association networks of Tangjiahe lower altitude network (Tangjiahe LAN) and Wolong LAN. In Tangjiahe LAN, the giant panda had symmetric associations with two species: the Asiatic golden cat (Catopuma temminckii) and Temminck’s tragopan (Tragopan temminckii). In Wolong LAN, the panda was directly associated with six species. Three types of associations were found in Wolong NNR. The first type was mutually asymmetric association between the panda and the Sichuan snub-nosed monkey (Rhinopithecus roxellanae), in which the two species benefited from each other. The second type was a uni-directional asymmetric association between the giant panda and the red panda (Ailurus fulgens), in which the giant panda benefited from the red panda. The third type was symmetric association between the giant panda and other four species, including the Asiatic black bear (Ursus thibetanus), yellow-throated marten (Martes flavigula), sambar (Rusa unicolor), and tufted deer (Elaphodus cephalophus), in which they competed for similar ecological resources. In Heizhugou NNR, species didn’t form a network and the giant panda was not directly associated with any species. Accordingly, it is suggested that conservation resources be invested on Wolong NNR in the case of resources shortage, because it will ensure the giant panda to further survive easier and, at the same time, will also benefit more other species in surviving. It is also suggested that the state budget currently made for ecological restoration be made with priority to Heizhugou, helping the natural community to recover in the NNR.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective
To investigate changes in interhemispheric imbalance of cortical excitability during motor recovery after stroke and to clarify the relationship between motor function recovery and ...alterations in interhemispheric imbalance, with the aim to establish more effective neuromodulation strategies.
Methods
Thirty-one patients underwent assessments of resting motor threshold (RMT) using transcranial magnetic stimulation (TMS); the cortical activity of the primary motor cortex (M1), premotor cortex (PMC), and supplementary motor area (SMA) using functional near-infrared spectroscopy (fNIRS); as well as motor function using upper extremity Fugl-Meyer (FMA-UE). The laterality index (LI) of RMT and fNIRS were also calculated. All indicators were measured at baseline(T
1
) and 1 month later(T
2
). Correlations between motor function outcome and TMS and fNIRS metrics at baseline were analyzed using bivariate correlation.
Results
All the motor function (FMA-UE
1
, FMA-UE
2
, FMA-d
2
) and LI-RMT (LI-RMT
1
and LI-RMT
2
) had a moderate negative correlation. The higher the corticospinal excitability of the affected hemisphere, the better the motor outcome of the upper extremity, especially in the distal upper extremity (
r
= −0.366,
p
= 0.043;
r
= −0.393,
p
= 0.029). The greater the activation of the SMA of the unaffected hemisphere, the better the motor outcome, especially in the distal upper extremity (
r
= −0.356,
p
= 0.049;
r
= −0.367,
p
= 0.042). There was a significant moderate positive correlation observed between LI-RMT
2
and LI-SMA
1
(
r
= 0.422,
p
= 0.018). The improvement in motor function was most significant when both LI-RMT
1
and LI-SMA
1
were lower. Besides, in patients dominated by unaffected hemisphere corticospinal excitability during motor recovery, LI-(M1 + SMA + PMC)
2
exhibited a significant moderate positive association with the proximal upper extremity function 1 month later (
r
= 0.642,
p
= 0.007).
Conclusion
The combination of both TMS and fNIRS can infer the prognosis of motor function to some extent. Which can infer the role of both hemispheres in recovery and may contribute to the development of effective individualized neuromodulation strategies.
At present, theoretical analysis, numerical simulation, and other methods cannot be used to properly solve the problems associated with the stability and bearing capacity of the surrounding rock and ...its supporting system, the interaction between the supporting structure and surrounding rock, and the sharing role of each supporting structure, all of which commonly occur in deep tunnels. The model test method represented by the photoelastic test is still an important approach to study this kind of problem. In view of the deficiency of the current loading system of the photoelastic model test, we developed a geo-stress loading system for the photoelastic model test, which can simulate the in situ geo-stress environment of unidirectional loading, bidirectional equal pressure, bidirectional unequal pressure, and tridirectional unequal pressure. The universal retaining force loading rod can realize the stability and effective compensation of loading, which is an original design. According to the principle of umbrella-shaped expansion and contraction mechanism, an excavation unloading device for the photoelastic model test is developed, which can realize the simulation of various degrees of displacement release in the excavation process of deep tunnels and other underground projects. The loading simulation test and excavation unloading simulation test show that the geo-stress loading system and excavation unloading device developed in this paper are flexible, exhibit good performance, and can fully achieve their respective test functions. The combination of two devices can compensate for the insufficiency of the current photoelastic model test and will promote the application of photoelastic model tests in underground engineering applications such as deep tunnel projects.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
By considering the characteristics of bionics theory of non-smooth surfaces to reduce the frictional resistance of a body, theoretical analysis of bionic jet surface was carried out based on the ...shark gill slits. Experimental and simulation methods were employed in order to study the drag reduction characteristics and drag reduction mechanism on gyroidal objects of bionic jet surface. Friction torque was tested by using a torque signal coupler on a smooth surface experimental model and bionic jet surface experimental models on many groups of different rotation speeds, and then the jet drag reduction characteristics and friction torque characteristics curves were obtained. Numerical simulation was used with SST k–ω turbulence model at the optimum rotation speed, and the characteristics of the smooth surface and the bionic jet surface were analyzed. Results show that the bionic jet surface has remarkable drag reduction effect, and the drag reduction rate is related to the rotational speed of the experimental model, the jet aperture and the jet velocity. The calculated results were closer to the experimental results; the numerical simulation results were a little higher than the experimental results, but the value was in the allowed error tolerance range, which dictated that the calculating way is right. The numerical simulation conformation to the experiments on the drag reduction rate will further verify the drag reduction characteristics of the bionic jet surface. The surface of jet flow thickens the viscous bottom of the boundary layer in the downstream field of the jet hole and decreases the wall shear stress. Meanwhile, there is a low-speed vortex in the downstream field which further thickens the viscous bottom and decreases the wall shear stress, and this is the reason why friction resistance decreases.
•We propose a method for drag reduction based on shark gills jet.•Drag reduction characteristics and drag reduction mechanism are studied.•Drag reduction rate is compared between experiments and numerical simulation.•Viscous bottom thickened and wall shear stress decreased.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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