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Abstract Bio-inspired composites with hexagonal platelet and cylindrical inclusions were studied. A novel algorithm termed staggered hardcore algorithm (SHCA) was used to rapidly generate 3D periodic representative volume elements (RVE) for bio-inspired composites with staggered non-uniformly dispersed inclusions. The spatial dispersions of inclusions in these generated RVEs were assessed using autocorrelation analysis, demonstrating the effectiveness of the SHCA algorithm. Orthotropic elastic properties of two different bio-inspired composites were computed and compared with analytical models, namely modified shear-lag, Mori-Tanaka and Halpin-Tsai, as well as available experimental data from the literature. For lower inclusion volume fractions, the computed results correlated well with experimental data and the analytical results. However, for higher inclusion volume fractions and aspect ratios the analytical results diverged, particularly Mori-Tanaka and modified shear-lag models which was similarly reported in previous studies. The capabilities of the computational model were further demonstrated through a comparative study of orthotropic elastic constants for the cylindrical and hexagonal inclusion composites. The study revealed the necessity to use 3D micromechanical models with realistic inclusion dispersions for accurately assessing the response of high inclusion volume fraction bio-inspired composites. [ABSTRACT FROM AUTHOR]

Generating realistic non-uniformly distributed three-dimensional representative volume element (RVE) for modeling the response of high fiber volume fraction composites is challenging. A novel rapid approach employing a random event-driven molecular dynamics simulation (EDMD) was proposed in this study for this purpose. Distributions of continuous unidirectional fibers in the RVEs were assessed using two approaches, namely Voronoi tessellations and radial distribution functions. The developed method was highly efficient in generating RVEs with realistic fiber dispersions. Furthermore, applying the corresponding periodic boundary conditions (PBCs) for finite element modeling is also arduous. A technique was developed within the commercial finite element software ABAQUS to rapidly produce required matching mesh patterns on opposite surfaces of the RVE, and to apply the corresponding PBCs using custom scripts. By coupling the EDMD approach and custom scripts within ABAQUS to rapidly generate and mesh RVEs with high fiber volume fractions, evaluation of the RVE response was greatly simplified. In- and out-of-plane elastic properties of unidirectional glass/epoxy composite in a range of 10–80% fiber volume fractions were determined and compared with analytical models, and available experimental data, with good correlation. [ABSTRACT FROM AUTHOR]

In order to investigate the largest motor vehicle ownership load within the scope of a city with atmospheric environmental indicators as constraint, this article estimates traffic atmospheric environmental capacity (TAEC) and carrying capacity (TAECC) in Tianjin using the A-value method recommended by the Chinese national standard. Our results indicate that NO X carrying capacity is a key restraining factor of TAEC. According to the current vehicle emission levels per year and air quality standard, Tianjin can accommodate 4.21 million vehicles. Classified by the vehicle type, heavy trucks and large-sized passenger cars are identified as the most important restrictive factors of TAECC. Then we analyze change of TAECC and TAECC’s service life under the circumstances of clean vehicle strategy and mobility management strategy. Clean vehicles strategy represented by the elimination of heavy-polluting vehicles can reduce emissions of vehicles so that it can rapidly enhance the TAECC in the short term. Mobility management strategy represented by the car purchase restriction, which reduces total motor vehicle travel, is indispensable for improvement of TAECC in the long term. On the whole, the clean vehicles strategy and mobility management strategy should be implemented gradually. [ABSTRACT FROM AUTHOR]

Quick and accurate diagnosis for malignant thyroid nodules via ultrasonography is a valuable but challenging task even for experienced radiologists because of the complexity and variability of ultrasound images. Many computer-aided diagnosis (CAD) methods have been proposed to assist radiologists by providing objective suggestions. However, most existing segmentation approaches lack the ability to keep precise shape information and capture global long-range dependencies. To settle the above issues, we propose a deep learning-based CAD method called Transformer fusing CNN Network (TCNet) to segment malignant thyroid nodules automatically. Our proposed TCNet contains a large kernel CNN branch and an enhanced Transformer branch. In the former branch, we devise a Large Kernel Module (LKM) to extract the precise shape features of malignant thyroid nodules in ultrasound images. While in the latter branch, we design an Enhanced Transformer Module (ETM) to establish the remote connection between thyroid nodule pixels. To integrate multiscale feature maps produced from different phases of both branches, we develop a Multiscale Fusion Module (MFM) to connect the two branches. We compare the proposed model with several current commonly used segmentation methods on the MTNS dataset and other public datasets. The experimental results demonstrate the superiority and effectiveness of our method. • We propose Transformer fusing CNN Network (TCNet) for thyroid nodule segmentation. • We design the Large Kernel Module (LKM) to capture shape of thyroid nodule. • We propose the Enhanced Transformer Module (ETM) to model long-range relations. • We introduce the Multiscale Fusing Module (MFM) to connect the two branches. • We build a malignant thyroid nodule segmentation (MTNS) dataset. [ABSTRACT FROM AUTHOR]

Grass carp, bighead carp, and silver carp spawn in flowing water. Their eggs, and then larvae, develop while drifting. Hydraulic conditions and water temperature control spawning locations, egg survival, and the downstream distance traveled before the hatched larvae can swim for low velocity nursery habitats. Existing egg drift models simulate the fluvial transport of carp eggs but have limitations in capturing the effect of localized turbulence on egg transport due to inadequate dimensions of hydrodynamics and/or empirical parameterization of river dispersion. We present a three-dimensional Lagrangian particle tracking model that uses fully resolved river hydrodynamics and a continuous random walk algorithm driven by local turbulent kinetic energy and its dissipation rate. We incorporate a new set of equations to compute evolving egg characteristics with fully resolved 3-D hydrodynamics. To demonstrate the performance of the model, we conducted a case study in an eight-kilometer reach of the Missouri River at the discharge of approximately 25% daily flow exceedance. Three-dimensional river hydrodynamics was modeled, calibrated, and evaluated with measurement data. Egg drift was modeled and compared using fully three-dimensional, depth-averaged two-dimensional, and zone-averaged one-dimensional hydrodynamics. The comparison shows a generally good agreement among models of downstream egg transport due to advection but a different dispersion pattern of eggs in the river, as a result of turbulent diffusion and shear induced dispersion. • A model was developed to simulate drifting of fish eggs in large rivers. • The effects of localized turbulence on egg drift are included in the model. • Turbulent transport is modeled using realistic particle tracking algorithms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and performance of novel hybrid bead-type chiral stationary phases. • Hybrid beads containing organic contents of higher than 30 wt%. • Prepared from cellulose derivative and tetraethyl orthosilicate by a sol–gel process. • Different surfactants influences morphology, organic contents and chiral recognition. • Higher enantioselectivity was exhibited on the obtained CSPs than Chiralpak IB. Due to the regular backbone structure and high chiral recognition ability, polysaccharide derivatives have become most attractive polymer-based candidates for preparation of chiral stationary phases (CSPs) for efficient enantioseparation. However, the traditional polysaccharide-based CSPs usually took up 20 wt% organic contents, implying that only a small proportion of the CSPs had favorable contribution to their enantioseparation properties. To break through this limitation, seven hybrid bead-type CSPs bearing organic components of higher than 30 wt% have been prepared from cellulose tris(3,5-dimethylphenylcarbamates) (CDMPC) and tetraethyl orthosilicate by a sol–gel process. The influence of three types of surfactants on morphology, organic content and particle size of the hybrid bead-type CSPs was carefully investigated. Cetyltrimethyl ammonium bromide (CTAB), a cationic surfactant with a longer alkyl chain, seemed to be favorable to obtain the hybrid CSPs with a high yield and regular morphology. Then their enantioseparation performance was evaluated by high-performance liquid chromatography (HPLC). The hybrid CSPs containing more organic components exhibited stronger enantioseparation power than those with lower organic contents and previous analogue CSP. For some chiral compounds, the hybrid bead-type CSPs exhibited higher enantioselectivity than Chiralpak IB, which is also prepared from CDMPC and one of the most attractive commercialized CSPs nowadays. A higher loading capacity shown by the hybrid CSPs is beneficial for efficient enantioseparation of chiral compounds, especially for preparative purpose. [ABSTRACT FROM AUTHOR]

Rockburst is one of the leading disasters in mining and rock engineering causing serious casualties and property losses. A major engineering challenge for underground roadways in mines experiencing significant seismicity is the performance of the support system. Applicability of energy-absorbing support system was studied basing on a novel facility, and the support performance was compared with that of the ordinary rock bolt support under the same simulated geology conditions. The results demonstrate that the modelled roadway still kept in good condition after several successive impacts with increasing energy level, suggesting that the roadway retained its resistance to dynamic loads at that time. The bursting failure occurred suddenly when the dynamic loading energy reached a certain critical level. Significant differences of acceleration signals from two roadway sections with different support types appeared, indicating that the energy-absorbing support could greatly change the shock behaviour of the roadway under dynamic loading. A very significant decrease in acceleration amplitudes was produced by the good shock resistance of the roadway section supported with additional energy-absorbing elements to perfect absorbing shock energy of the roadway structure. During the bursting failure, roadway section with traditional rock bolt support was severely damaged and almost closed, while the front roadway section supported by additional energy-absorbing elements remained in relative good condition. The combination of energy-absorbing elements and rock bolt support provides a very efficient and ductile support type in extreme burst-prone conditions. [ABSTRACT FROM AUTHOR]

• Bubble sizes and population have strong impacts on velocity, width, and fluxes of volume and momentum in bubble plumes. • Bubble impacts are attributed to different mechanisms of energy and momentum transport in the flow. • Integral model is a valid tool to characterize the bubble plume for different bubble sizes and population. We present an experimental study to investigate the impact of bubble size on behavior of bubble plumes from the integral point of view. Two distinct types of bubble plume were generated under the same volumetric gas flow rate: many small bubbles using an air-stone diffuser and a few large bubbles using a single-orifice diffuser. Using Particle Image Velocimetry, we measured the velocity field in the plumes, and derived the integral characteristics for comparison, including the evolution of plume width, centerline velocity, volume flux, momentum flux, momentum amplification factor, and the entrainment coefficient. The measurement data show that the evolution of all the parameters in the plumes are influenced strongly by the different bubble sizes and population. The plumes with many small bubbles behave closer to the single-phase coherent plumes, showing a linear growth of plume width and a decreasing centerline velocity. These characteristics are modified in the plumes with fewer but larger bubbles. With the same total initial buoyancy flux from the source, fewer but larger bubbles give rise to weaker mean flow characteristics, i.e., smaller plume velocity and weaker fluxes of volume and momentum. This modification is attributed to the different mechanisms in fundamental transport of energy and momentum between mean and fluctuating components. In the single-orifice cases, the plumes are influenced by stronger but less frequent bubble wakes, compared to those more coherent bubble plumes in the air-stone cases. Higher momentum amplification factors were found in bubble plumes with fewer but larger bubbles, indicating a stronger ratio of turbulence to mean in these plumes. Despite the modification, all bubble plumes support a typical shear entrainment process within 40 cm height-of-rise. Hence, the integral model and the universal scaling using the plume length scale D and the bubble slip velocity W s were found to describe the integral behavior of bubble plumes generally well in the range of our experimental parameters, regardless of the different bubble sizes and population. [ABSTRACT FROM AUTHOR]

Objective The purpose of the present study was to comprehensively compare the phenotype profile of infiltrated macrophages in human noncalcified and calcific aortic valves, and to determine whether the shift of macrophage polarization modulates valvular calcification in vitro. Methods Cell surface markers of macrophages and inflammatory cytokines expression in 90 cases of human noncalcified and calcific aortic valve leaflets were analyzed. The normal aortic valve interstitial cells were isolated and cultured in vitro. After incubation with nonconditioned medium and conditioned medium from unstimulated or lipopolysaccharide-stimulated U937 monocytes, valve interstitial cells were evaluated by osteogenic differentiation markers. Results Infiltration of macrophages was enhanced in the calcific aortic valves, and M1 phenotype was the predominant macrophage subsets. In addition, both proinflammatory and anti-inflammatory cytokines were significantly upregulated in the calcific aortic valves. Furthermore, lipopolysaccharide-stimulated monocytes presented with increased expression of inducible nitric oxide synthase and high proportional CD11c-positive (M1) macrophages. Conditioned medium from unstimulated monocytes promoted the osteogenic differentiation of valve interstitial cells in vitro, as evidenced by increased markers such as bone morphogenetic protein 2, osteopontin, and alkaline phosphatase. Conditioned medium from M1 macrophages further enhanced valve interstitial cells calcification. Enzyme-linked immunosorbent assay showed that M1 phenotype macrophages secreted tumor necrosis factors α and interleukin 6, and neutralizing antibodies to these 2 proinflammatory cytokines attenuated induction of osteogenic differentiation and calcification by the conditioned media. Conclusions Both total numbers and polarization of macrophage influence the process of calcification in human aortic valve. The shift toward M1 phenotype might promote valve interstitial cell calcification. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive approach for evaluating agroecosystems based on an embodied cosmic exergy investigation. This novel methodology is applied to three distinctive systems: farmland-biogas (F-B), farmland-dairy (F-D) and farmland-dairy-biogas (F-D-B) systems. A comparison of renewability and sustainability among the F-B, F-D and F-D-B systems is conducted to demonstrate this framework. The results show that over 50% of the total cosmic exergy inputs for the F-D-B system can be ascribed to purchased and free renewable resources, which is much higher than the other two systems. The net present ecological value ( NPEV ) of the F-D-B system is approximately 6 times higher than that of the F-B and F-D systems. The sustainability of the F-D-B system is 2.76 and 2.08 times higher than that of the F-D and F-B systems, respectively. The economic benefit ( EB ) of the F-D-B system is the highest of all three systems. These results suggest that the F-D-B system is superior to the other two systems. This study contributes to providing a theoretical foundation for policy-making in the rural regions of China. [ABSTRACT FROM AUTHOR]

Background: Ethyl chloride spray as a common cooling modality has been widely used in acute sports injuries and joint injection procedures. Several clinical studies reported that use of ethyl chloride has positive effects on swelling, pain reduction and recovery from sports injuries. The main aim of present study was to analyze whether postoperative use of ethyl chloride spray benefits results after primary total knee arthroplasty (TKA).Methods: Between April 1, 2014 and October 21, 2015, 306 subjects undergoing primary TKA used ethyl chloride spray for improving recovery from the damage from surgery. After exclusion of 31 subjects due to adverse events including periprosthetic joint infection (PJI), deep venous thrombosis (DVT), acute myocardial infarction, finally 275 subjects' data regarding pain score, knee range of motion (ROM), knee girth, time of being able to reach 90° knee flexion and analgesic consumption were analyzed.Results: Significant differences in pain score, knee ROM at each time point and knee girth at on 21st and 28th postoperatively were detected without increased incidence of adverse events. Besides, time of being able to reach 90° knee flexion and analgesic consumption in the treatment group were significantly decreased in comparison to the control group.Conclusion: Use of ethyl chloride spray can help patients recovery from the damage from TKA safely. [ABSTRACT FROM AUTHOR]

Background: B-type natriuretic peptide (BNP) is a well-known biomarker to predict cardiac events following orthopedic procedures. However, further information regarding BNP can be completed. The present study aims to determine which of preoperative, postoperative or the difference between them (DVPPB) can best predict adverse cardiac events following TKA procedure and detect possible risk factors of high level of BNP.Methods: Between Jan. 2012 and Jan. 2014. 1120 included patients in 3 institutions have a minimum of 2-years follow-up. All clinical characteristics related to TKA procedure were put in total joint arthroplasty registry system and analyzed finally. The cut-off value of BNP predicting patients at increased risks of cardiac events after TKA was evaluated by the Receiver Operating Characteristic (ROC) curve analysis.Results: Our results reveal DVPPB in comparison to preoperative and postoperative BNP can best predict cardiac events following primary TKA, and the optimal cut-off value was 825.5 pg/ml with the highest Youden index of 0.62. Cigarette smoking, ASA III/IV/V, prior history of cardiac events, general anesthesia, surgery time, and tourniquet time are risk factors for DVPPB > 825.5 pg/ml.Conclusions: DVPPB in comparison to preoperative and postoperative BNP can best predict cardiac events following primary TKA. Cigarette smoking, ASA III/IV/V, prior history of cardiac events, general anesthesia, surgery time, and tourniquet time are risk factors for DVPPB > 825.5 pg/ml. We hope these results could be helpful to optimize health care among patients undergoing primary TKA. [ABSTRACT FROM AUTHOR]

Background: Total knee arthroplasty (TKA) is primarily preformed among the elderly population who is commonly affected by cardiovascular and cerebrovascular diseases. Atrial fibrillation (AF) is a very common heart disease and its prevalence increases significantly with age. Therefore, we decided to evaluate the outcomes of patients with AF following TKA and analyze the risk factors of AF patients who underwent postoperative complication.Methods: We designed a retrospective cohort study using data from three institutions in China. We evaluated a total of 453 AF patients who received primary TKA and 453 matched control patients. Comparisons of specific parameters between AF and non-AF cohorts were performed.Results: Our results demonstrated that AF patients had significantly higher odds of more intraoperative bleeding, periprosthetic joint infection (PJI), post-operative cerebral stroke (POCS), post-operative cardiovascular events (POCE) and worse SF-36 physical component score and mental score at mean 24-month after surgery, but had no increased incidence of post-operative gastrointestinal events, DVT and PE in comparison to patients without AF than those without AF disease. Additionally, multivariate logistic regression analysis was used to identify risk factors of patients who underwent severe complication. Smoking, diabetes mellitus and persistent AF were common risk factors of PJI, POCS, and POCE. Heart rate＞70/min and absence of Beta blocker use were common risk factors of POCS and POCE. Absence of LMWH bridging was risk factor of POCS. BMI >25 kg/m2 and hypertension were risk factors of POCE.Conclusions: These findings should be taken into consideration when discussing the expected outcomes of AF patients after TKA. AF disease impaired SF-36 physical component score (PCS) and mental component score (MCS) of patient after TKA. [ABSTRACT FROM AUTHOR]