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OBJECTIVE To analyze the myocardial involvement and explore the strain characteristics of the left atrium and the left ventricle in patients with Fabry disease (FD) using conventional echocardiography and 2-dimensional speckle tracking echocardiography (2D-STE). METHODS A retrospective study was conducted. Sixty-nine patients with FD who were treated in the Department of Cardiology, Neurology and Nephrology of Peking University First Hospital from August 2014 to February 2023 and underwent echocardiography examination in the Cardiology Department were collected (FD group). During the same time, 69 age- and sex-matched individuals who had no cardiovascular, cerebrovascular, renal, metabolic, and autoimmune diseases, and had no obvious abnormalities on echocardiography were included in the control group. The clinical data and laboratory tests were collected, and routine echocardiography and 2D-STE were performed to analyze left atrial strain and left ventricular longitudinal strain. The differences in relevant parameters between groups were compared. RESULTS Compared with the control group, the patients in the FD group had smaller body mass index and body surface area, slower heart rate, poorer estimated glomerular filtration rate, and significantly increased brain natriuretic peptide and cardiac troponin I (all P < 0.05). E'med in the FD group was reduced (8.4 ± 3.4 vs. 9.9 ± 2.8, P = 0.006) and E peak, E peak deceleration time, pulmonary artery systolic pressure increased, interventricular septum and left ventricular posterior wall thickened, left ventricular mass index, and early diastolic transmitral inflow velocity/septal mitral annular velocity (E/Eʹ) increased (all P  < 0.05). Compared with the control group, left atrial strains [including left atrial strain during reservoir phase (LASr), left atrial strain during contraction phase (LASct), left atrial strain during conduit phase (LAScd)] and left ventricular average global longitudinal strain (GLSavg) were reduced in the FD group. In the segmental longitudinal strain of the left ventricular, the strain was significantly reduced except for the strain of the basal and middle segment of the inferior wall (P  < 0.05). CONCLUSIONS Patients with FD usually have multisystem involvement such as kidney and heart. Echocardiography usually shows varying degrees of myocardial hypertrophy and diastolic dysfunction, while left ventricular ejection fraction is normal. Left atrial strain, left ventricular global, and segmental longitudinal strain are all decreased to varying degrees. [ABSTRACT FROM AUTHOR]

Variations in pavement density have been widely monitored and investigated, both in laboratory and in field experiments, since the compaction of pavement is so critical to its long-term performance quality. In contrast to field testing, laboratory tests are simpler to produce but less accurate. Destructive drilled samples are used to conduct field testing; however, they are limited in their ability to assess density information at specific areas. The use of computationally aided approaches, such as the Finite Element Method (FEM) and the Discrete Element Method (DEM), in research involving asphalt mixtures is increasing, since these methods simulate and evaluate the characteristics of asphalt mixtures at macroscopic and microscopic scales. Individual particle behavior at the microscopic level cannot be fully represented using the FEM alone, and the computing cost of utilizing the DEM approach alone is prohibitively high. The objective of this work is to simulate the pre-compaction process by using the coupled FEM-DEM approach. In order to investigate the impact of the asphalt mixtures' gradation, a dense-graded asphalt mixture (AC 11) and a gap graded asphalt mixture (PA 11) were simulated. Different paving speeds (4, 5, and 6 m/min) were applied on the preliminary compaction model of AC 11 to study the effect of the paving speeds on the compaction process. By comparing the angular velocity, which worked as a reference of compaction quality, it was demonstrated that the grade AC 11 asphalt mixtures performed better in the preliminary compaction process compared to the grade PA 11 asphalt mixtures. Moreover, since it has an effect on compaction, paving speed was carefully monitored and kept within a reasonable range in order to maximize both pavement quality and project efficiency. [ABSTRACT FROM AUTHOR]

In this paper, the role of crushing operation on the cubical controlling features of coarse aggregates, and its influence on the shape distribution characteristics of aggregates (i.e. angularity, sphericity, and flatness & elongation ratio) were investigated through the second version of Aggregate Image Measuring System (AIMS II). Three types of aggregate from different origins were chosen and crushed by the vertical shaft impactor (VSI) with fixed rotational speed. The results indicate that the rotation speed of VSI is influenced by the input power of the machine to the particle sizes, and higher speed leads to more cracks on aggregates during the crushing process. By using X-ray diffraction (XRD), the aggregate samples from different origins and mineral compositions were analysed under the same working operation of crusher. Besides that, the correlation between particle shape characteristics influenced by the mineralogical composition, and their collision behaviours have been discussed according to the tested results. A recommendation for optimal operation of VSI on crushing granite aggregates is given based on this study. Whereas, the cubical condition of aggregates and energy saving factors were taken into account. Furthermore, petrographic analyses were imposed to correlate particle mineralogy to its collision behaviour during crushing. [ABSTRACT FROM AUTHOR]

The geochemical characteristics and Pb isotope variations in Fe-Mn deposits collected from the South China Sea (SCS) were studied in this paper. The mineralogical and chemical composition data indicate that the deposits are almost all hydrogenetic in origin. Compared with the Fe-Mn deposits in other oceans, the SCS Fe-Mn deposits have a significantly higher Pb content because of higher material supply in addition to a lower growth rate of the deposits. Pb isotope ratios in the surface of the SCS Fe-Mn deposits are relatively uniform, with a characteristic of relatively lower 206Pb/204Pb ratio. The Pb isotopic compositions of the SCS Fe-Mn deposits are controlled by the Pacific Deep Water and local inputs, which include eolian dust from the Asian continent and weathering products from Taiwan, Luzon and SCS submarine volcanic rocks. The continuously increasing 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios along the transect of nodule D581 over the past 3.5 Ma are affected by the stepwise closure of the Luzon Strait that reduced volcanic material supply and the deep current strengthen at the same time. [ABSTRACT FROM AUTHOR]

This study investigated the effect of cellulase on the isolation of crude Astragalus polysaccharide (APS), analyzed the monosaccharide component of deproteinized APS, detected the molecular weights of purified APS, and examined the biological activities and the preliminary mechanism against rheumatoid arthritis (RA). Compared with water extraction method, cellulase-assisted extraction increased the yield of crude APS to 154% and polysaccharide contents to 121%. Crude APS was then purified by ethanol precipitation, Sevag deproteinization, and high-performance liquid chromatography (HPLC) analysis; monosaccharide contents of APS were different after cellulase-assisted method, especially galacturonic acid content which significantly increased. DEAE-52 cellulose column chromatography isolated three polysaccharide fractions, including a neutral polysaccharide (APS-water) and two acidic polysaccharides (APS-NaCl1 and APS-NaCl2). Using high-performance gel permeation chromatography (HPGPC), the molecular weights of APS-water, APS-NaCl1, and APS-NaCl2 were identified as 67.7 kDa, 234.1 kDa, and 189.4 kDa, respectively. Then their therapeutic effects and possible mechanism against RA were explored using type II collagen-induced arthritis (CIA) rat model. APS could significantly reduce paw swelling, serum concentration of IL-1β and TNF-α, and the expression levels of NF-κB-p65 and IκBα in synovial membranes in CIA rats. Our study indicated that cellulase significantly increases the yield and polysaccharide contents of crude APS, improves the product quality, and preserves the biological features against RA in CIA rats. [ABSTRACT FROM AUTHOR]

Crack distress causes asphalt pavement failure under repeated traffic loading. The objective of this study is to investigate the fracture properties of asphalt concrete through three dimensional (3D) numerical simulation using finite element method (FEM). The parameters and datum utilised for finite element models were captured from a grey matrix, which can be converted from digital images scanned by an X-ray computed tomography (CT) apparatus. Afterwards, the uniaxial compression test was simulated using FEM and was also conducted in laboratory to study the stress distribution and to evaluate the degree of damage during the loading process. Eighteen cylindrical asphalt concrete specimens were prepared with three different types of gradations: asphalt concrete, stone matrix asphalt and open-graded friction course. The uniaxial compression test was carried out on these specimens. Before and after each step, the specimens were scanned using X-ray CT to analyse the crack growth behaviour inside the asphalt concrete and to investigate the effect of gradation on the fracture characteristics. The degree of fracture can be evaluated by data analysis from the grey intensity histogram. The evaluation on asphalt concrete crack properties based on FEM with X-ray CT imaging was found to be practicable and reproducible. Additionally, the gradation was found to be an influential factor affecting the crack propagation of asphalt concrete. [ABSTRACT FROM AUTHOR]

Background: The production of inflammatory cytokines resulting from amyloid β (Aβ) is associated with the initiation of Alzheimer's disease (AD). Atorvastatin (ATV) has been reported to improve AD, however, it is unclear how the anti-inflammatory mechanism is linked with its protection against the impairment of spatial cognitive function in AD. The present study was designed to explore what mechanism was possibly involved in the anti-inflammatory pathway in regard to the ATV treatment of AD.Methods: We used an AD model induced by the administration of Aβ(25-35) in male C57BL/6 mice and an in vitro culture system to study the protective effects of ATV on the spatial cognitive deficits, hippocampal long-term potentiation (LTP) impairment and inflammatory reaction.Results: The intragastric administration of ATV (5 mg/kg) in Aβ(25-35)-treated mice significantly ameliorated the spatial cognitive deficits and prevented the LTP impairment in hippocampal CA1. The increased Iba-1 positive cells and inflammatory components in the hippocampus were reduced after the ATV treatment. The anti-inflammatory and LTP protection of ATV were abolished using the replenishment of farnesyl pyrophosphate by the administration of farnesol (FOH). The hippocampal slices culture showed Aβ(25-35)-induced neurotoxicity in the absence of the presence of ATV. Treatment with ATV (0.5, 1, 2.5 μmol/L) dose-dependently prevented the cell damage in hippocampus induced by Aβ25-35.Conclusion: The administration of ATV ameliorated the cognitive deficits, depressed the inflammatory responses, improved the LTP impairment, and prevents Aβ25-35-induced neurotoxicity in cultured hippocampal neurons. These protective functions of ATV involved the pathway of reducing farnesyl pyrophosphate (FPP). [ABSTRACT FROM AUTHOR]

The coupling between variables in the multi-input multi-output (MIMO) systems brings difficulties to the design of the controller. Aiming at this problem, this paper combines the particle swarm optimization (PSO) with the coefficient diagram method (CDM) and proposes a robust controller design strategy for the MIMO systems. The decoupling problem is transformed into a compensator parameter optimization problem, and PSO optimizes the compensator parameters to reduce the coupling effect in the MIMO systems. For the MIMO system with measurement noise, the effectiveness of CDM in processing measurement noise is analyzed. This paper gives the control design steps of the MIMO systems. Finally, simulation experiments of four typical MIMO systems demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Pavement pre-compaction is vital for asphalt pavement construction due to its influence on the quality and service life of asphalt pavement. Conventional methods of evaluating and researching the pavement pre-compaction are based on mixture density with empirical theories, which cannot provide an understanding of asphalt-screed interaction during pre-compaction. An innovative approach is developed in this paper to evaluate pavement pre-compaction through Discrete Element Model (DEM) simulation. The contact model and input parameters were discussed and defined separately based on the real condition of paving compaction. A field test about paving compaction was conducted as well for the model validation, in the test track, the operations of paving machine can be adjusted such as paving speed, paving angle, and paving thickness. In addition, the optimized working operation was recommended in this paper based on the results from DEM simulation as well as filed test. Finally, a method to evaluate the pre-compaction of bulk materials via the average aggregate angular velocity was proposed in this study and validated through the test track, and the index Compaction Increase Ratio (CIR) was defined to compare and describe the quality of pre-compaction. [ABSTRACT FROM AUTHOR]

Continuously increasing traffic volumes necessitate accurate design methods to ensure the optimal service life and efficient use of raw materials. Numerical simulations commonly pursue a simplified approach with homogeneous pavement materials and homogeneous loading. Neither the pavement geometry nor the loading is homogeneous in reality. In this study, the mechanical response of the asphalt mixtures due to homogeneous loads is compared with their mechanical response to inhomogeneous loads. A 3D finite element model was reconstructed with the aid of X-ray computed tomography. Sections of a real tire's pressure distribution were used for the inhomogeneous loads. The evaluation of the material response analyzes the stress distribution within the samples. An inhomogeneous load evokes an increased proportion of high stresses within the sample in every case, particularly at low temperatures. When comparing the two types of loads, the average stresses on the interior (tension and compression) exhibit significant differences. The magnitude of the discrepancies shows that this approach yields results that differ significantly from the common practice of using homogeneous models and can be used to improve pavement design. [ABSTRACT FROM AUTHOR]

The Semi-Flexible Water Retaining Pavement (SFWRP) has the capability to cool down the temperature of the road surface through its evaporation behavior, including absorbing and evaporating water; this is an efficient approach to relieve the heat island effect in a big city. The temperature feedback from different material surface were investigated in this paper in the same test condition, it has been proved that the SFWRP material can remarkably cool down the temperature of the road surface. The mechanism of the material evaporation behavior, including flux calculation formula of the water vapor inside the air void, were studied by inter-phase continuous function, in which the structural properties of the SFWRP material was taken into account. Furthermore, the function calculating the evaporation of the water vapor was then developed in this research through heat and mass transfer analogy. Besides, the calculating results can be captured by the self-coding program in Finite Element Modeling (FEM) for water evaporation simulation. Also, the results of laboratory tests were adopted to validate the calculating model. Finally, it has been proved that the mortar was recommended to be used in semi-flexible water retaining pavement to serve as material with permeable and water retaining property, and the semi-flexible water retaining pavement material is recommended to applied in the surface layer of the permeable pavement. [ABSTRACT FROM AUTHOR]

Focuses on the prognostic significance of heart rate variability (HRV) in post-myocardial infarction patients. Statistics of patients with acute myocardial infarction; Prevention of cardiac death; Concerns over the value of HRV.

Abstract: Drug-eluting stents (DES) have greatly reduced the possibility of in-stent restenosis by inhibiting neointimal growth. But recently stent fracture has emerged as a complication. Stent fracture may cause restenosis, even occlusion. Here we report a case of stent fracture after percutaneous coronary intervention with DES without restenosis. [Copyright &y& Elsevier]