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The hydroxyapatite nanoparticles (nHAPs) were synthesized rapidly by the self-assembled dual-frequency ultrasonic method. The ultrasonic time and power effect on the morphology and phase composition of nHAPs were investigated through field-emission scanning electron microscopy (FE-SEM), X-ray diffraction, energy dispersive spectrometer (EDS) spectrometer, and Fourier transform infrared spectroscopy, which showed that the most uniform nanoparticles were obtained when the ultrasonic time was 30 min and the ultrasonic power was 280 W. Cytotoxicity and hemolysis tests showed that an indistinctive cytotoxic effect was within the concentration of 25–400 μg/mL and the hemolytic ratio was below 2.0% at concentration of 25–200 μg/mL, respectively, revealing a good biocompatibility of nHAPs. By loading tetracycline hydrochloride onto nHAPs spheres, the drug release results showed that the drug loading and encapsulation efficiency were (26.34 ± 2.99)% and (52.68 ± 5.98)%, respectively. The drug-loaded sample shows a slow-release property, indicating that nHAPs may be promising as drug carriers.
Investigate short- and long-term effects of Superstorm Sandy on multiple morbidities among the elderly.
We examined emergency department visits; outpatient visits; and hospital admissions for cardiovascular disease (CVD), respiratory disease, and injury among residents residing in 8 affected counties immediately, 4 months, and 12 months following Superstorm Sandy. Control groups were defined as visits/admissions during the identical time window in the 5 years before (2007-2011) and 1 year after (2013-2014) the storm in affected and nonaffected counties in New York. We performed Poisson regression to test whether there was an association of increased visits/admissions for periods following Superstorm Sandy while controlling for covariates.
We found that the risk for CVD, respiratory disease, and injury visits/admissions was more than twice as high immediately, 4 months, and 12 months after the storm than it was in the control periods. Women were at greater risk at all time periods for CVD (risk ratio [RR], 2.04) and respiratory disease (RRs: 1.89 to 1.92). Whites had higher risk for CVD, respiratory disease, and injury than other racial groups during each period.
We observed increases in CVD, respiratory disease, and injury up to a year following Superstorm Sandy. Findings demonstrate the need to incorporate short- and long-term health effects into public health recovery. (Disaster Med Public Health Preparedness. 2019;13:28-32)
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.
The morphology, composition, and structure of precipitates in an Al–Si–Mg–Hf alloy after heat treatment at 560°C for 20 h were studied by means of Cs-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectrometry (EDS), high-resolution transmission electron microscopy (HRTEM), and first-principle calculations. Precipitates with three kinds of morphologies were observed. The rectangular and square precipitates were predominantly (Si2−xAlx)Hf phases, while the nanobelt-like precipitate is the Si2Hf phase. First-principle calculations were used to show that the Si6 and Si8 sites were the most favorable sites for Al incorporation in the orthorhombic Si2Hf phase.
The effects of pre-treatments on the precipitate microstructures of an Al–Zn–Mg–Cu alloy are investigated. Meanwhile, the creep-rupture behavior of the under-aged and peak-aged alloys are comparatively analyzed. Additionally, the effects of pre-treatment on the fracture mechanisms are discussed. It is found that the precipitate microstructures are sensitive to pre-treatments. The intragranular precipitates of the peak-aged alloy are larger than those of the under-aged. The precipitate free zone of the peak-aged alloy is wider than that of the under-aged. Some large intergranular precipitates appear on the grain boundaries of the under-aged alloy, and induce the nucleation of microvoids. Eventually, the creep fracture of the under-aged alloy is accelerated. Therefore, the differences in microstructures lead to the shorter creep-rupture life of the under-aged alloy, compared to the peak-aged alloy.
This is a case-control study to investigate the prevalence, characteristics, and risk factors of pain in patients with Parkinson's disease (PD).
A total of 200 PD patients from eastern China were enrolled in our study. Accordingly, 200 healthy elderly adults were recruited as controls. The characteristics of pain were collected by using the Visual Analog Scale, Brief Pain Inventory (BPI), SF-36 Bodily Pain Scale, Unified Parkinson's Disease Rating Scale, Hoehn–Yahr Scale (H-Y), Hamilton Depression Scale, and Leeds Assessment of Neuropathic Symptoms and Signs.
Of the 200 PD patients, pain was complained by 106 patients (53%). According to the SF-36 Bodily Pain Scale, pain morbidity in PD patients was significantly higher than in the control group. The average pain during last 24 h measured by the BPI was 2.67. About 76% of PD patients were found to have one pain type, 21.7% were having two pain types, and 1.9% had three pain types. Further, 69.8% of these patients were presented with musculoskeletal pain, 4.7% with dystonic pain, 22.6% with radicular-neuropathic pain, 20.8% with central neuropathic pain, and 9.4% with akathisia pain. The onset age and depression were the most significant predictors of pain in PD patients (p < 0.05). However, there was no significant association between pain and gender, age, disease duration, or severity of the disease. Only 5.7% of PD patients with pain received treatment in this study.
Pain is frequent and disabling, independent of demographic and clinical variables, and is significantly more common in PD patients.
We have developed efficient numerical algorithms for solving 3D steady-state Poisson-Nernst-Planck (PNP) equations with excess chemical potentials described by the classical density functional theory (cDFT). The coupled PNP equations are discretized by a finite difference scheme and solved iteratively using the Gummel method with relaxation. The Nernst-Planck equations are transformed into Laplace equations through the Slotboom transformation. Then, the algebraic multigrid method is applied to efficiently solve the Poisson equation and the transformed Nernst-Planck equations. A novel strategy for calculating excess chemical potentials through fast Fourier transforms is proposed, which reduces computational complexity from O(N2) to O(NlogN), where N is the number of grid points. Integrals involving the Dirac delta function are evaluated directly by coordinate transformation, which yields more accurate results compared to applying numerical quadrature to an approximated delta function. Numerical results for ion and electron transport in solid electrolyte for lithiumion (Li-ion) batteries are shown to be in good agreement with the experimental data and the results from previous studies.
Experimental observations show that a strong magnetic field has a dramatic influence on the sedimentation of RBCs, which motivates us to model the sedimentation of red blood cell (RBC) under strong external magnetic body force. To model the sedimentation of a RBC in a square duct and a circular pipe, a recently developed technique derived from the lattice Boltzmann and the distributed Lagrange multiplier/fictitious domain methods (LBM-DLM/FD) is extended to employ the mesoscopic network model for simulations of the sedimentation of a RBC in flow. The flow is simulated by the LBM with a strong magnetic body force, while the network model is used for modeling RBC deformation. The fluid-RBC interactions are enforced by the Lagrange multiplier. The sedimentation of RBC in a square duct and a circular pipe is simulated, which demonstrates the developed method's capability to model the sedimentation of RBCs in various flows. Numerical results illustrate that the terminal settling velocity increases incrementally with the exerted body force. The deformation of RBC has a significant effect on the terminal settling velocity due to the change in the frontal area. The larger the exerted force, the smaller the frontal area and the larger the RBC deformation become. Additionally, the wall effect on the motion and deformation of RBC is also investigated.
In this paper, we present an adaptive, analysis of variance (ANOVA)-based data-driven stochastic method (ANOVA-DSM) to study the stochastic partial differential equations (SPDEs) in the multi-query setting. Our new method integrates the advantages of both the adaptive ANOVA decomposition technique and the data-driven stochastic method. To handle high-dimensional stochastic problems, we investigate the use of adaptive ANOVA decomposition in the stochastic space as an effective dimension-reduction technique. To improve the slow convergence of the generalized polynomial chaos (gPC) method or stochastic collocation (SC) method, we adopt the data-driven stochastic method (DSM) for speed up. An essential ingredient of the DSM is to construct a set of stochastic basis under which the stochastic solutions enjoy a compact representation for a broad range of forcing functions and/or boundary conditions.
Our ANOVA-DSM consists of offline and online stages. In the offline stage, the original high-dimensional stochastic problem is decomposed into a series of low-dimensional stochastic subproblems, according to the ANOVA decomposition technique. Then, for each subproblem, a data-driven stochastic basis is computed using the Karhunen-Loève expansion (KLE) and a two-level preconditioning optimization approach. Multiple trial functions are used to enrich the stochastic basis and improve the accuracy. In the online stage, we solve each stochastic subproblem for any given forcing function by projecting the stochastic solution into the data-driven stochastic basis constructed offline. In our ANOVA-DSM framework, solving the original highdimensional stochastic problem is reduced to solving a series of ANOVA-decomposed stochastic subproblems using the DSM. An adaptive ANOVA strategy is also provided to further reduce the number of the stochastic subproblems and speed up our method. To demonstrate the accuracy and efficiency of our method, numerical examples are presented for one- and two-dimensional elliptic PDEs with random coefficients.
In this study, we present a new numerical model for crystal growth in a vertical solidification system. This model takes into account the buoyancy induced convective flow and its effect on the crystal growth process. The evolution of the crystal growth interface is simulated using the phase-field method. A semi-implicit lattice kinetics solver based on the Boltzmann equation is employed to model the unsteady incompressible flow. This model is used to investigate the effect of furnace operational conditions on crystal growth interface profiles and growth velocities. For a simple case of macroscopic radial growth, the phase-field model is validated against an analytical solution. The numerical simulations reveal that for a certain set of temperature boundary conditions, the heat transport in the melt near the phase interface is diffusion dominant and advection is suppressed.
This paper investigates the modulational instability of a linearly polarized ultra-intense laser pulse propagating in electron–positron plasmas. Based on the wave equation, which contains vacuum polarization and magnetization effects, the nonlinear dispersion relation and the growth rate of instability are obtained and the effects of plasma number density and laser intensity on the growth rate are analyzed. Numerical results show that if the laser intensity is high enough, the modulational instability growth rate induced by vacuum polarization and magnetization nonlinearity can dominate the modulational instability growth rate induced by the nonlinearity associated with a relativistic effect and ponderomotive force.
Little is known about the role of oxidative stress in the pathogenesis of vascular dementia (VaD). The aim of this study was to investigate the biomarkers of oxidative stress in urine, as reflected by 8-hydroxydeoxyguanosine (8-OHdG), 8-isoprostaglandin F2a (8-isoPGF2a) and nitrotyrosine (NT) levels, in a group of well characterized VaD patients and in two control groups of Vascular Not Demented (VaND) patients and healthy subjects.
Ninety-six subjects from the Tianjin municipality in China were recruited. Forty-six patients were in the VaD group, 24 patients with VaND and 26 persons with no signs of cognitive disorder were employed as control groups. Urinary 8-OHdG and 8-isoPGF2a was performed using enzyme-linked immunosorbent assay (ELISA), and urinary NT levels were measured by chemiluminescence detection.
Significantly higher urinary 8-OHdG levels were detected in VaD patients compared to VaND patients and healthy control subjects. In contrast, urinary 8-isoPGF2a levels were significantly lower in VaD patients compared with two control groups. For NT levels, no statistically significant differences were observed among the three groups.
Increased urinary 8-OHdG level was a potential marker of oxidative stress in VaD patients. Furthermore, it is also important to take into account potential confounders in order to improve the identification of changes in the status of oxidative stress as related to VaD.
An efficient implementation of PNP-cDFT, a multiscale method for computing the chemical potentials of charged species is designed and evaluated. Spatial decomposition of the multi particle system is employed in the parallelization of classical density functional theory (cDFT) algorithm. Furthermore, a truncation strategy is used to reduce the computational complexity of cDFT algorithm. The simulation results show that the parallel implementation has close to linear scalability in parallel computing environments. It also shows that the truncated versions of cDFT improve the efficiency of the methods substantially.
The pathological mechanism of restenosis is primarily attributed to excessive proliferation of vascular smooth muscle cells (VSMC). The preventive effects of ethanol extract of Dunaliella salina (EDS) on balloon injury-induced neointimal formation were investigated. To explore its molecular mechanism in regulating cell proliferation, we first showed that EDS markedly reduced the human aortic smooth muscle cell proliferation via the inhibition of 5′-bromo-2′-deoxyuridine (BrdU) incorporation at 40 and 80 μg/ml. This was further supported by the G0/G1-phase arrest using a flow cytometric analysis. In an in vivo study, EDS at 40 and 80 μg/ml was previously administered to the Sprague–Dawley rats and found that the thickness of neointima, and the ratio of neointima:media were also reduced. EDS inhibited VSMC proliferation in a dose-dependent manner following stimulation of VSMC cultures with 15 % fetal bovine serum (FBS). Suppressed by EDS were 15 % FBS-stimulated intracellular Raf, phosphorylated extracellular signal-regulated kinases (p-Erk) involved in cell-cycle arrest and proliferating cell nuclear antigen. Phosphorylated focal adhesion kinase (p-FAK) was also suppressed by EDS. Also active caspase-9, caspase-3 and cleaved poly(ADP-ribose) polymerase (PARP) protein expression levels were increased by administration with EDS; the apoptotic pathway may play an important role in the regulatory effects of EDS on cell growth. These observations provide a mechanism of EDS in attenuating cell proliferation, thus as a potential intervention for restenosis.
5-AZA-2′-deoxycytidine (5-AZA-CdR) is a demethylating, teratogenic agent and a mutagen, which causes defects in the developing mouse and rat after implantation. Our previous data indicated that 5-AZA-CdR (0.2 and 1.0 μM) inhibited the development of mouse preimplantation embryos. Pronuclear embryos exposed to 5-AZA-CdR at the pronuclear stage were unable to form 8-cell embryos, while 2-cell-stage embryos exposed to 5-AZA-CdR only developed into uncompacted 8-cell-stage embryos. And there was no formation of blastocysts when 4-cell embryos cultured in 5-AZA-CdR. In our present study, we detected Dnmt1o protein and some developmental gene expression in order to find the reasons for the developmental arrest. Dnmt1o could not traffic to 8-cell nuclei as control when embryos were exposed to 5-AZA-CdR. Dnmt1o was in cytoplasm at 2-cell and 4-cell stages before and after treated with 5-AZA-CdR. Gene expression changes were also detected in this research. Our data indicated that connexin 31 (Cx31), connexin 43 (Cx43), connexin 45 (Cx45), E-cadherin (Cdh1) and β-catenin (Ctnnb1) were all downregulated by 5-AZA-CdR. Cx31, Cx43 and Cx45 are members of connexins family, which have a central role in gap junctions. Cdh1 and Ctnnb1 are necessary for the foundation of tight junctions. Therefore, developmental arrest induced by 5-AZA-CdR may be caused by the failure of Dnmt1o cytoplasmic–nuclear traffic and the down-regulation of developmental gene expression. Normal compaction and blastocoel cavitation need Dnmt1o traffic to 8-cell nuclei and the right gene expression, especially the correlative genes in gap junctions and tight junctions.
The expression of the YUCAA1 gene and the amount of endogenous indole acetic acid (IAA) in rice (Oryza sativa subsp. japonica) plants and rice suspension cells infected by Rice stripe virus (RSV) were investigated by real-time reverse transcriptase–polymerase chain reaction (RT-PCR) and high-performance liquid chromatography, respectively. The results showed that the expression of the YUCAA1 gene and the amount of endogenous IAA increased at various times (16, 32, 48 and 64 h) after infection of rice suspension cells by RSV. In rice plants infected with RSV, the expression of the YUCAA1 gene and the amount of endogenous IAA increased, in comparison with healthy rice plants, at 4–8 days after infection, and decreased at 12 and 16 days. These results indicated that RSV infection could regulate auxin biosynthesis in rice. Additionally, the expression of the RSV gene CP increased 2.9 times in rice plants after they were treated with a KPSC buffer to deplete the endogenous auxins, and decreased 45% after treatment with 30 μmol/l IAA. All of these results suggest that auxin may play a role in RSV replication in rice plants.
The testosterone-inducible regulator (teiR) gene was cloned from Comamonas testosteroni chromosomal DNA, and introduced into plasmids pKtac2 (containing a tac promoter) and pK18 to yield plasmids pKtac2-teiR and pKteiR100. The recombinant plasmids were transformed into competent Escherichia coli HB101 and total protein was extracted to detect the TeiR protein expression level using enzyme-linked immunosorbent assay (ELISA). E. coli transformed by pKtac2-teiR and pKteiR100 produced 6.65 and 5.93 μg/mg of TeiR protein, respectively. Recombinant plasmids were also co-transformed into competent E. coli HB101 with plasmid p6 [containing hsdA gene (3α-HSD/CR, 3α-hydroxysteroid dehydrogenase/carbonyl reductase encoding gene)] to reveal the relationship between 3α-HSD/CR and TeiR by ELISA. The amounts of TeiR protein expressed by E. coli containing pKtac2-teiR and pKteiR100 were 5.94 μg/mg and 5.33 μg/mg, respectively, and these increased up to 6.81 μg/mg and 6.10 μg/mg after inducing with 1 mmol/l isopropyl-β-d-thiogalactoside (IPTG). Interestingly, 3α-HSD/CR protein expression level, after co-transformation with plasmids pKtac2-teiR and p6, was lower than that observed in the co-transformation with pKteiR100 and p6. The first co-transformation induced 1.20 μg/mg 3α-HSD/CR protein and the second 1.71 μg/mg. These values rose to 1.42 and 1.80 μg/mg, respectively, after treatment with 1 mmol/l IPTG. Our results proved that the tac promoter was more efficient than the lacZ promoter and that the teiR gene could act as an activator for hsdA gene expression.
An AlGaAs/InGaAs HEMT grown on Si substrate with Ge/GexSi1−x buffer is demonstrated. The Ge/GexSi1−x metamorphic buffer layer used in this structure was only 1.0 μgm thick. The electron mobility in the In0.18Ga0.82 As channel of the HEMT sample was 3,550 cm2/Vs. After fabrication, the HEMT device demonstrated a saturation current of 150 mA/mm and a maximum transconductance of 155 mS/mm. The well behaved characteristics of the HEMT device on the Si substrate are believed to be due to the very thin buffer layer achieved and the lack of the antiphase boundaries (APBs) formation and Ge diffusion into the GaAs layers.