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This article investigates the removal of ammonium from aqueous solutions using zeolite synthesized from fly ash by a fusion method, which combines alkaline fusion followed by hydrothermal treatment. The cation exchange capacity increases from 0.03 to 2.79 meq/g during the synthesis process. The effects of contact time, pH, initial ammonium concentration, adsorbent dosage, and the presence of other cations and anions are examined by batch experiments. The findings show that these parameters have significant effects on the ammonium removal using the synthesized zeolite. The effect of cations follows the order K . The Lagergren first-order, Ho' pseudo-second-order, and intraparticle diffusion kinetic models are employed to describe the kinetic data, and Ho' pseudo-second-order model provides excellent fitting. The equilibrium isotherm data are fitted to the Langmuir, Freundlich, Koble-Corrigan, Tempkin and Dubinin-Radushkevich models; the Koble-Corrigan model gives the best fit. The thermodynamic study reveals that ammonium uptake by the synthesized zeolite is an exothermic reaction. The maximum ammonium uptake capacity obtained is 24.3 mg/g. The regenerated zeolite has almost the same ammonium uptake capacity as the original zeolite. These results indicate that the synthesized zeolite is a promising material for removing ammonium from wastewater.

Background: Children aged 6-7 years are in the early mixed dentition, which is a period of high prevalence of dental caries and other dental diseases and a critical period for the formation of oral health behaviors. Therefore, good oral hygiene habits of children and oral health knowledge of parents are very important. This study sought to explore the relationship between children's oral health behaviors, parental oral health knowledge, parental choices of pit and fissure sealants, and parents' education levels based on a large-scale sample size for the first time, and to compare the influences of parental education levels between parents. Methods: Families of the first and second graders of primary schools in Wuhan Hongshan District were included in this study. A total of 8446 questionnaires were collected to obtain comprehensive information on children's oral health behaviors, parents' oral health knowledge and parents' pit and fissure sealants-related choices. The relationship between these outcome variables and parents' education levels were studied using logistic regression analysis and chi-square test. Results: Parents who reported good educational background had more favorable oral health knowledge than those of other parents, and their children had better oral hygiene behaviors. Four indicators of five measures to children's oral health behaviors were significantly associated with mother's education level (P < 0.05), and three of them were related to father's education level (P ≤ 0.01). Moreover, seven indicators of eight measures to parents' oral health knowledge were significantly related to mother's education level (P < 0.05) and four of them were affected by the father's (P < 0.05). In addition, parents with higher educational attainments paid more attention to the completeness of medical facilities, the environment of dental practice, the distance to treatment sites, and took less concern of children's willingness when choosing the pit and fissure sealants sites.

Ginsenoside Rh2 inhibits proliferation, migration and invasion and induces apoptosis of the human pancreatic cancer cell line Bxpc-3.

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Mesenchymal stem cells (MSCs) are known to have the potential for articular cartilage regeneration, and are suggested for the treatment of osteoarthritis (OA). Here, we investigated whether intra-articular injection of xenogeneic human adipose-derived mesenchymal progenitor cells (haMPCs) promoted articular cartilage repair in rabbit OA model and engrafted into rabbit articular cartilage. The haMPCs were cultured in vitro, and phenotypes and differentiation characteristics of cells were evaluated. OA was induced surgically by anterior cruciate ligament transection (ACLT) and medical meniscectomy of knee joints. At six weeks following surgery, hyaluronic acid (HA) or haMPCs was injected into the knee joints, the contralateral knee served as normal control. All animals were sacrificed at the 16th week post-surgery. Assessments were carried out by macroscopic examination, hematoxylin/eosin (HE) and Safranin-O/Fast green stainings and immunohistochemistry. The data showed that haMPC treatment promoted cartilage repair. Signals of human mitochondrial can be directly detected in haMPC treated cartilage. The haMPCs expressed human leukocyte antigen I (HLA-I) but not HLA-II-DR in vivo. These results suggest that intra-articular injection of haMPCs promotes regeneration of articular cartilage in rabbit OA model, and support the notion that MPCs are transplantable between HLA-incompatible individuals.

Keywords:Low-calcium fly ash High-calcium fly ash Synthesized zeolite Ammonium removal Select criteria of raw fly ash In this study, zeolites are synthesized from low-calcium (LC-Z) and high-calcium (HC-Z) fly ashes, respectively. The changes of mineralogy, morphology, cation exchange capacity (CEC) and specific surface area (SSA) are investigated during the synthesis process. The equilibrium uptake of ammonium on the two synthesized zeolites is compared. The main crystals of LC-Z and HC-Z are identified as faujasite and gismondine, respectively. The CEC and SSA increase significantly following the conversion process. The kinetic studies showed that the adsorption process of ammonium on both LC-Z and HC-Z follows Ho's pseudosecond-order model. Langmuir model agrees better with the equilibrium data for LC-Z, while Freundlich model gives the better fit for HC-Z. The obtained maximum ammonium uptake capacities are 23.8 mg/g for LC-Z and 3.17 mg/g for HC-Z in the synthetic solution. LC-Z also exhibits much better performance in ammonium uptake in effluent from a sewage treatment plant than HC-Z. These results indicate that LC-Z is a promising material for ammonium removal whereas HC-Z is not. The Ca 2+ leaching and the lower zeolite content in HC-Z account for its lower uptake capacity. Thus, the low-calcium fly ash should be chosen preferentially as the raw material of the zeolite synthesis for ammonium removal.

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