Porous carboxymethyl chitosan (PCMC) beads were synthesized
via
ionic coacervation/chemical crosslinking, using polyethylene glycol (PEG) as a porogen and calcium chloride and glutaraldehyde as ...physical and chemical cross-linkers. The as-synthesized PCMC beads were characterized using SEM, EDS, BET, TGA, FTIR and XPS analysis and then tested for the removal of Co(
ii
) from aqueous solution. The effects of the initial pH, Co(
ii
) concentration and temperature were investigated. It was found that the adsorption equilibrium is reached within 6 h and the maximum adsorption capacity is 46.25 mg g
−1
. In addition, the kinetics and equilibrium data are well described by pseudo-second-order kinetics and the Langmuir isotherm model. Moreover, the desorption and re-adsorption performance was also studied, and the results revealed that the prepared new adsorbent still showed good adsorption performance after five cycles of regeneration. Finally, the adsorption mechanism, including chemical and physical adsorption, was proposed on the basis of the microstructure analysis, adsorption kinetics and isotherm results, and chemical adsorption was found to be the main adsorption mechanism during the process of the removal of Co(
ii
).
The as-prepared adsorbent exhibits excellent adsorption capacity and fast kinetics for Co(
ii
).
In this article, morphology, structure and size controllable chitosan microspheres with high mechanical strength were synthesized by microfluidic technology combining chemical crosslinking and used ...as an adsorbent for methyl orange. The synthesized adsorbents were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and an Energy Dispersive Spectrometer (EDS). The effect of pH revealed that the adsorption process depended on pH and the pH variation of methyl orange solution after adsorption indicated that adsorption capacity was affected through the associated role of chitosan nature and pH variation. Experimental results suggested that the as-prepared chitosan microspheres were controlled within a narrow size distribution (coefficients of variation is 1.81%), whose adsorption capacity reached to 207mg·g−1 and mechanical strength was suitable to resist forces. In addition, the adsorption isotherm was well fitted with the Langmuir model, and the adsorption kinetic was best described by the pseudo-second-order kinetic model. The high performance microfluidic-synthesized chitosan microspheres have promising potentials in the applications of removing dyes from wastewater.
In this work, the authors considered the periodic optimal control problem of Fitzhugh-Nagumo equation. They firstly prove the existence of time-periodic solution to Fitzhugh-Nagumo equation. Then ...they show the existence of optimal solution to the optimal control problem, and finally the first order necessary condition is obtained by constructing an appropriate penalty function.
In this paper, we consider network models for marketing consumer durables based on the classical Bass model, derived using the degree-based mean field theory. For the annealed network setting, we ...establish its equilibria, stability, and positivity properties. For the quenched network setting, we first review a model using the edge-based compartmental modeling approach, which agrees well with the ensemble means of the stochastic marketing process. Then, we extend the model to include dynamic advertising rate, which accounts for the fact that advertising may become less efficient and have less impact on people’s choice with the reduction of potential buyers, and individual consciousness, allowing nodes to become alerted to the fact individuals are purchasing the product in the population and therefore reinforce their aspiration. Finally, we perform extensive numerical simulations to explore the effect of dynamic advertising rate and individual consciousness on the marketing durables. Numerical results show that there may exist a trade-off in maximizing the fraction of adopters in the population and minimizing the cost associated with advertising in practical applications.
Second-order nonlinear multi-agent system whose agents could be divided into multiple subgroups is considered in this paper. In order to avoid congestion, lag group consensus of the considered system ...is investigated via adaptive protocol. Without constraint on the topology of the system, sufficient conditions for the lag group consensus are proposed analytically. Finally, the efficiency of the proposed methodology is illustrated by numerical simulation.
As total joint replacement is widely applied for severe arthropathy, peri-prosthetic aseptic loosening as one of the main causes of implant failure has drawn wide attention. Wear particles such as ...titanium particles (TiPs) derived from prosthesis can initiate macrophages inflammation and sequentially activate osteoclasts, which results in bone resorption and osteolysis for long-term. Therefore, inhibiting wear particles induced macrophages inflammation is considered as a promising therapy for AL. In this research, we found that the inhibition of p110δ, a member of class IA PI3Ks family, could significantly dampen the TiPs-induced secretion of TNFα and IL-6. By the transfection of siRNA targeting p110δ, we confirmed that p110δ was responsible for TNFα and IL-6 trafficking out of Golgi complex without affecting their expression in TiPs-treated macrophages. As the upstream transcription-repressor of p110δ, Krüppel-like factor 4 (KLF4), targeted by miR-92a, could also attenuate TiPs-induced inflammation by mediating NF-κB pathway and M1/M2 polarization. To further ascertain the roles of KLF4/p110δ, TiPs-induced mice cranial osteolysis model was established and vivo experiments validated that KLF4-knockdown could exacerbate TiPs-induced osteolysis, which was strikingly ameliorated by knockdown of p110δ. In summary, our study suggests the key role of miR-92a/KLF4/p110δ signal in TiPs-induced macrophages inflammation and osteolysis.
As shown in our previous studies, growth and metastasis of ovarian cancer can be regulated by adipose-derived mesenchymal stem cells (ADSCs). However, the underlying mechanism has not yet been ...revealed. In this study, a proteomics analysis was performed to compare protein expression treated with and without ADSCs in ovarian cancer cells. Protein levels were altered in ovarian cancer cells due to the treatment of ADSCs. Thymosin beta 4 X-linked (TMSB4X) levels changed dramatically, and this protein was identified as one of the most important candidate molecules contributing to the tumour-promoting effects of ADSCs. Compared with the cells that are cultured in the normal growth medium, the TMSB4X levels cultured in ADSC-conditioned medium increased significantly in ovarian cancer cells. Furthermore, the growth and invasion of cancer cells were decreased, even in the ADSC-conditioned medium treatment group (P<0.05), by the inhibition of TMSB4X. As shown in the bioluminescence images captured in vivo, increased ovarian cancer’s growth and metastasis, along with elevated TMSB4X expression, were observed in the group of ADSC-conditioned medium, and the tumour-promoting effect of ADSCs was attenuated by the inhibition of TMSB4X. Based on our findings, increased TMSB4X expression may play a role in accelerating the ADSC-mediated proliferation, invasion, and migration of ovarian cancers.
Objective
Wear particles induce inflammation and the further osteolysis around the prosthesis, has been proven to be the main cause of aseptic hip joint loosening. In this research, we aimed to ...clarify whether human umbilical cord mesenchymal stem cells (HUCMSCs) could inhibit the titanium particles‐induced osteolysis and shed light upon its mechanism.
Methods
The expression of chemokine (C‐C motif) ligand 2 (CCL2), chemokine (C‐C motif) ligand 3 (CCL3) and chemokine (C‐C motif) ligand 5 (CCL5) were examinjed in clinical specimens of aseptic hip prosthesis loosening patients. Local injection of lentivirus that knocked down CCL2 or CCL3 in a cranial osteolysis mice model were used to exam the effect of CCL2 and CCL3 on titanium particles‐induced osteolysis in vivo. Transwell assay was used to examine the effect of CCL2 and CCL3 on titanium particles‐induced activation of macrophage in vitro. Furthermore, the therapeutic effect of HUCMSCs, and exosomes from HUCMSCs were also examed in vivo and vitro. Immunohistochemical and real‐time PCR were used to examine the expression of relative pathways. Analysis of variance (ANOVA) and Student–Newman–Keuls post hoc t test were used to analyze the results and determine the statistical significance of the differences.
Results
Results showed that titanium particles caused the osteolysis at the mice cranial in vivo and a large number of macrophages that migrated, while local injection of HUCMSCs and exosomes did inhibit the cranial osteolysis and migration. An exosome inhibitor GW4869 significantly increased the osteolysis area in the mice cranium osteolysis model, and increased the number of migrated macrophages. Immunohistochemical results suggested that the expression of CCL2, CCL3 and CD68 in the cranial in Titanium particles mice increased significantly, but was significantly reduced by HUCMSCs or exosomes. HUCMSC and exosomes down‐regulate the expression of CCL3 in vitro and in vivo.
Conclusion
HUCMSCs and HUCMSC‐derived exosomes could suppress the titanium particles‐induced osteolysis in mice through inhibiting chemokine (C‐C motif) ligand 2, chemokine (C‐C motif) ligand 3.
Studies showed that mesenchymal stem cells have the ability in immune regulation. In this research, A Cranial osteolysis mice model was established to examine the effect of human umbilical cord mesenchymal stem cells (HUCMSCs). Results showed HUCMSCs and it's exosomes suppressed the expression of CCL2 and CCL3 and inhibit the cranial osteolysis and migration of macrophage.
Hepatitis C virus (HCV) infection is one of the leading causes of liver cancer, creating enormous economic and social burdens. The Chinese government recommends routine screening of inpatients for ...HCV before invasive procedures to prevent iatric infections. However, the diagnosis and treatment rates for HCV remain low. The aim of this study was to use available routine screening data to understand the HCV screening of inpatients in different regions of China.
Inpatient information and HCV screening results were collected from January 2016 to December 2016 at eight tertiary hospitals in different regions of China to compare the HCV-positivity of hospitalized patients among different regions and age groups.
The HCV screening rate of inpatients was more than 50%. A total of 467,008 inpatients were enrolled in the study (51.20% were male), and the HCV antibody (anti-HCV) -positive rate was 0.88% (95% confidence interval CI, 0.85-0.91%) among the total population. This rate was significantly higher among all males compared with all females (0.91% vs 0.85%). Moreover, the HCV antibody-positive rate increased with age and was highest for the 60-64-year age group. Notably, 90.14% (3722/4129) of the anti-HCV seropositive patients were 40 years of age or older. HCV screening for people over 40 years old is recommended.
This study highlights the key role of routine examination for HCV infection in hospitalized patients. Full use of inpatient screening results to manage HCV antibody-positive patients and a screening strategy targeting inpatients 40 years and older were found to be low-cost and effective, which will help to find the missing millions of yet unaware patients and also accelerate the elimination of HCV in China.
This paper mainly discusses the asymptotic behaviors on the minimizers of convex processes. In view of the convexity argument, it is proved that the minimizers of convex processes with parameterized ...objective functions satisfy the functional moderate deviation principle. As some applications, the estimators in two basic models (threshold regression models and stochastic dynamical systems) are studied. In particular, the exponential convergence principles on the estimators converging to true parameters are proved.
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