Lubricant-infused surfaces hold promise to reduce the huge frictional drag that slows down the flow of fluids at microscales. We show that infused Teflon wrinkled surfaces induce an effective slip ...length 50 times larger than expected based on the presence of the lubricant alone. This effect is particularly striking as it occurs even when the infused lubricant's viscosity is several times higher than that of the flowing liquid. Crucially, the slip length increases with increasing air content in the water but is much higher than expected even in degassed and plain Milli-Q water. Imaging directly the immersed interface using a mapping technique based on atomic force microscopy meniscus force measurements reveals that the mechanism responsible for this huge slip is the nucleation of surface nanobubbles. Using a numerical model and the height and distribution of these surface nanobubbles, we can quantitatively explain the large fluid slip observed in these surfaces.
The wing is one of the most important parts of a bird's locomotor system and is the inspiration origination for bionic wing design. During wing motions, the wing shape is closely related to the ...rotation angles of wing bones. Therefore, the research on the law of bone movement in the process of wing movement can be good guidance for the design of the bionic morphing wing. In this paper, the skeletal posture of the peregrine falcon wing during the extension/flexion is studied to obtain critical data on skeletal posture. Since an elbow joint and a wrist joint rotate correlatively to drive a wing to flex/extend, the wing skeleton is simplified as a four-bar mechanism in this paper. The degree of reproduction of wing skeleton postures was quantitatively analyzed using the four-bar mechanism model, and the bionic wing skeleton was designed. It is found that the wing motions have been reproduced with high precision.
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With the rapid development of electric vehicle (EV) technology under the background of double carbon, a reasonable evaluation of the network planning of EV charging stations is conducive to the ...long-term stable development of the EV industry. Therefore, this paper proposes a comprehensive evaluation system and method for EV charging networks under the traffic network and power grid coupling. First, an EV travel model is developed based on the travel probability matrix to analyze the spatial and temporal characteristics of EVs. Secondly, the coupling relationship among users, charging network, road network, and the power grid is analyzed, four criteria of user feedback, charging network operation, road network operation impact, and power grid operation impact are proposed, and corresponding evaluation indexes are constructed under each criterion to form a comprehensive evaluation index system. Furthermore, the Analytic Hierarchy Process (AHP) and entropy weighting method are used to assign weights to the index layer and the criterion layer respectively, and the improved TOPSIS evaluation method is used to quantitatively analyze the impact of charging networks on different subjects for comprehensive evaluation. Finally, through the comprehensive evaluation of different charging network planning schemes, the effectiveness of the comprehensive evaluation method and model proposed in this paper is verified, which can provide a reference basis for the planning and improvement of EV charging station networks.
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Proterozoic strata have become a new target for hydrocarbon exploration worldwide. They exhibit the potential to become a resource replacement target. To provide a reference for hydrocarbon source ...rock evaluation, the sedimentary environment and mechanism of organic matter enrichment of dark shales in the Mesoproterozoic Cuizhuang Fm. were investigated for the first time by combining organic and inorganic research concepts. Although the total organic carbon (TOC) content in the Cuizhuang Fm. is relatively low (mean value of 0.59%), it still can be considered as a potential source rock. Thin-section observations, main and trace element contents, and biomarker compounds revealed the following: (1) the Cuizhuang Fm. was deposited in a neritic shelf sedimentary environment at a passive continental margin, and the climate was warm and humid. The hydrocarbon-generating organisms mainly comprised prokaryotes such as cyanobacteria and other bacteria. All these characteristics meet the conditions of source rock formation. (2) The low oxygen level, felsic source provenance, and absence of submarine hydrothermal activity led to low productivity, and the low productivity and low-grade hydrocarbon-generating organisms led to low TOC content in the Cuizhuang Fm. (3) The enrichment of V in the Cuizhuang Fm. is apparent, but does not reach the hyper-enrichment threshold of 500 ppm associated with euxinic conditions, revealing anoxic ferruginous conditions. Moreover, the V content is positively correlated with TOC content, indicating that organic matter enrichment was mainly controlled by the redox conditions of the bottom water. Therefore, the sedimentary areas with high productivity were related to basic source provenance and submarine hydrothermal activity, and anoxic bottom water may have promoted the development of better source rocks. This findings may represent the main direction for identifying effective source rocks in subsequent work.
•Sedimentary environments of the dark shales from Cuizhuang Fm. were studied, which satisfied the requirements of source rock formation.•The organic matter enrichment mechanism of the dark shales from Cuizhuang Fm. belongs to “preservation-type”.•The sedimentary areas with basic source provenances and active submarine hydrothermal activity may provide high productivity and form more abundant organic matter in the Mesoproterozoic.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ischemic stroke is the second leading cause of death worldwide with limited medications and neuroinflammation was recognized as a critical player in the progression of stroke, but how to control the ...overactive neuroinflammation is still a long-standing challenge. Here, we designed a novel SIRT6 activator MDL-811 which remarkably inhibited inflammatory response in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and primary mouse microglia, which were abolished by silencing SIRT6. RNA-seq screening identified the forkhead box C1 (Foxc1) is a key gene evoked by MDL-811 stimulation and is required for the anti-inflammatory effects of MDL-811. We found MDL-811-activated SIRT6 directly interacted with enhancer of zeste homolog 2 (EZH2) and promoted deacetylation of EZH2 which could bind to the promoter of Foxc1 and upregulate its expression to modulate inflammation. Moreover, our data demonstrated that MDL-811 not only ameliorated sickness behaviors in neuroinflammatory mice induced by LPS, but also markedly reduced the brain injury in ischemic stroke mice in addition to promoting long-term functional recovery. Importantly, MDL-811 also exhibited strong anti-inflammatory effects in human monocytes isolated from ischemic stroke patients, underlying an interesting translational perspective. Taken together, MDL-811 could be an alternative therapeutic candidate for ischemic stroke and other brain disorders associated with neuroinflammation.
SIRT6 activator MDL-811 activates SIRT6 to promote EZH2 deacetylation and further FOXC1 expression, resulting in amelioration of neuroinflammation and brain ischemic injury and further improvement of stroke outcomes. Display omitted
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The aim of this study was to quantitatively summarize the available evidence on the association of breastfeeding with the risk of childhood cancer.
A literature search of PubMed and Embase databases ...was performed to identify eligible observational studies published from inception to July 17, 2020. The categorical and dose-response meta-analysis was conducted by pooling relative risk (RR) or odds ratio (OR) estimates with 95% confidence intervals (CIs). Potential sources of heterogeneity were detected by meta-regression and stratification analysis. Sensitivity analysis and publication bias test were also carried out.
Forty-five articles involving 475,579 individuals were included in the meta-analysis. Among the thirty-three studies on the association between breastfeeding and risk of childhood leukemia, the pooled risk estimates were 0.77 (95% CI, 0.65-0.91) and 0.77 (95% CI 0.63-0.94) for ever versus non/occasional breastfeeding and longest versus shortest breastfeeding duration group, respectively. There was clear indication for non-linear dose-response relationship between breastfeeding duration and the risk of childhood leukemia (P non-linear < 0.001). The most protective effect (OR, 0.66, 95% CI 0.62-0.70) was observed at a breastfeeding duration of 9.6 months. Four studies examined, the association between breastfeeding and risk of childhood neuroblastoma, and significant inverse associations were consistently observed in both the comparisons of ever breastfeeding versus non/occasional breastfeeding (OR = 0.59, 95% CI 0.44-0.81) and longest versus shortest breastfeeding (OR = 0.61, 95% CI 0.44-0.83). However, no associations of breastfeeding with risk of other cancers were found.
Our study supports a protective role of breastfeeding on the risk of childhood leukemia, also suggesting a non-linear dose-response relationship. Further studies are warranted to confirm the association between breastfeeding and risk of childhood neuroblastoma.
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Here we report a new study on the boundary conditions for the flow of a simple liquid in a confined geometry obtained by measuring hydrodynamic drainage forces with colloid probe atomic force ...microscopy (AFM). In this work, we provide experimental data obtained using a best practice experimental protocol and fitted with a new theoretical calculation (Zhu, L.; Attard, P.; Neto, C. Langmuir 2010, submitted for publication, preceding paper). We investigated the hydrodynamic forces acting on a silica colloid probe approaching a hydrophobized silicon surface in a single-component viscous Newtonian liquid (di-n-octylphthalate), a partially wetting system. The measured average slip lengths were in the range of 24−31 nm at approach velocities of between 10 and 80 μm/s. Using our experimental approach, the presence of nanoparticle contaminants in the system can be indentified, which is important because it has been shown that nanoparticles lead to a large apparent slip length. Under our stringent control of experimental conditions, the measurement of the slip length is reproducible and independent of the spring constant of the cantilever.
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Background
There is a paucity of data regarding the prevalence of preoperative deep vein thrombosis (DVT) in patients with long bone (including femur, tibia and fibula) fractures of the lower limbs. ...We performed a meta-analysis to address the issue.
Methods
Electronic databases, including PubMed, EMBASE, the Web of Science, the Cochrane Library, the VIP database, CNKI, and the Wanfang database, were systematic searched for original articles that reported the prevalence of preoperative DVT in long bone fractures of the lower limbs from January 2016 to September 2021. The prevalence of preoperative DVT was pooled using random-effects models, and subgroups were established according to study type, detection method, sample size and fracture site.
Results
Twenty-three articles reporting on 18,119 patients were eligible. The overall pooled preoperative DVT prevalence was 24.1% (95% CI 19.3–28.8%). In different subgroups, the preoperative DVT prevalences were 18.2–27.3%, 15.2–28.6%, 23.1–24.9%, 18.2–26.0% and 23.2–23.4% for different study designs, sample sizes, age groups, detection methods and fracture sites, respectively.
Conclusions
Despite the heterogeneity among studies, this systematic review suggests that the prevalence of preoperative DVT, which may seriously affect the prognosis of patients, is high. Therefore, greater efforts should be devoted to the improvement of screening and prevention strategies for preoperative DVT in lower-extremity long bone fractures.
Level of Evidence:
Level III.
Trial Registration
The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database with the registration number CRD42022324706.
Traditional charging stations have a single function, which usually does not consider the construction of energy storage facilities, and it is difficult to promote the consumption of new energy. With ...the gradual increase in the number of new energy vehicles (NEVs), to give full play to the complementary advantages of source-load resources and provide safe, efficient, and economical energy supply services, this paper proposes the optimal operation strategy of a PV-charging-hydrogenation composite energy station (CES) that considers demand response (DR). Firstly, the operation mode of the CES is analyzed, and the CES model, including a photovoltaic power generation system, fuel cell, hydrogen production, hydrogen storage, hydrogenation, and charging, is established. The purpose is to provide energy supply services for electric vehicles (EVs) and hydrogen fuel cell vehicles (HFCVs) at the same time. Secondly, according to the travel law of EVs and HFCVs, the distribution of charging demand and hydrogenation demand at different periods of the day is simulated by the Monte Carlo method. On this basis, the following two demand response models are established: charging load demand response based on the price elasticity matrix and interruptible load demand response based on incentives. Finally, a multi-objective optimal operation model considering DR is proposed to minimize the comprehensive operating cost and load fluctuation of CES, and the maximum–minimum method and analytic hierarchy process (AHP) are used to transform this into a linearly weighted single-objective function, which is solved via an improved moth–flame optimization algorithm (IMFO). Through the simulation examples, operation results in four different scenarios are obtained. Compared with a situation not considering DR, the operation strategy proposed in this paper can reduce the comprehensive operation cost of CES by CNY 1051.5 and reduce the load fluctuation by 17.8%, which verifies the effectiveness of the proposed model. In addition, the impact of solar radiation and energy recharge demand changes on operations was also studied, and the resulting data show that CES operations were more sensitive to energy recharge demand changes.
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The yeast prion protein Sup35, which contains intrinsically disordered regions, forms amyloid fibrils responsible for a prion phenotype PSI⁺. Using high-speed atomic force microscopy (HS-AFM), we ...directly visualized the prion determinant domain (Sup35NM) and the formation of its oligomers and fibrils at subsecond and submolecular resolutions. Monomers with freely moving tail-like regions initially appeared in the images, and subsequently oligomers with distinct sizes of ∼1.7 and 3 to 4 nm progressively accumulated. Nevertheless, these oligomers did not form fibrils, even after an incubation for 2 h in the presence of monomers. Fibrils appeared after much longer monomer incubation. The fibril elongation occurred smoothly without discrete steps, suggesting gradual conversions of the incorporated monomers into cross-β structures. The individual oligomers were separated from each other and also from the fibrils by respective, identical lengths on the mica surface, probably due to repulsion caused by the freely moving disordered regions. Based on these HS-AFM observations, we propose that the freely moving tails of the monomers are incorporated into the fibril ends, and then the structural conversions to cross-β structures gradually occur.
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