Morphological and Functional Characteristics of Animal Models of Myocardial Fibrosis Induced by Pressure Overload

Myocardial fibrosis is characterized by excessive deposition of myocardial interstitial collagen, abnormal distribution, and excessive proliferation of fibroblasts. According to the researches in recent years, myocardial fibrosis, as the pathological basis of various cardiovascular diseases, has been proven to be a core determinant in ventricular remodeling. Pressure load is one of the causes of myocardial fibrosis. In experimental models of pressure-overload-induced myocardial fibrosis, significant increase in left ventricular parameters such as interventricular septal thickness and left ventricular posterior wall thickness and the decrease of ejection fraction are some of the manifestations of cardiac damage. These morphological and functional changes have a serious impact on the maintenance of physiological functions. Therefore, establishing a suitable myocardial fibrosis model is the basis of its pathogenesis research. This paper will discuss the methods of establishing myocardial fibrosis model and compare the advantages and disadvantages of the models in order to provide a strong basis for establishing a myocardial fibrosis model

Tetraethylenepentamine-modified cellulose-graft-poly(methyl acrylate) applicable for Pb(II) adsorption from aqueous solution

274-280Tetraethylenepentamine-modified cellulose-graft-poly(methyl acrylate) (Cell-g-PMA-TEPA), a polyamino-functionalized adsorbent for Pb(II), has been prepared via graft polymerization of methyl acrylate (MA) from surface of microcrystalline cellulose and subsequent amidation with tetraethylenepentamine (TEPA). Influence of initial pH and contact time on adsorption has also been investigated. The adsorption kinetic could be best represented by pseudo-second-order model, while equilibrium data fits well with Langmuir isotherm model, from which maximum adsorption capacity could be derived as 444.4 mg g-1. Further consecutive experiments indicate less than 10% loss in equilibrium adsorption capacity after five adsorption-desorption cycles

Tetraethylenepentamine-modified cellulose-graft-poly(methyl acrylate) applicable for Pb(II) adsorption from aqueous solution

Tetraethylenepentamine-modified cellulose-graft-poly(methyl acrylate) (Cell-g-PMA-TEPA), a polyamino-functionalized adsorbent for Pb(II), has been prepared via graft polymerization of methyl acrylate (MA) from surface of microcrystalline cellulose and subsequent amidation with tetraethylenepentamine (TEPA). Influence of initial pH and contact time on adsorption has also been investigated. The adsorption kinetic could be best represented by pseudo-second-order model, while equilibrium data fits well with Langmuir isotherm model, from which maximum adsorption capacity could be derived as 444.4 mg g-1. Further consecutive experiments indicate less than 10% loss in equilibrium adsorption capacity after five adsorption-desorption cycles

Evaluation of a Modified Monod Model for Predicting Algal Dynamics in Lake Tai

Several modified versions of the Monod model have been proposed to simulate algal dynamics in lakes by keeping the parent model’s advantages of simplicity and low data requirement. This study evaluated the performance of a widely-used modified Monod model in predicting algal dynamics at various time scales in Lake Tai, a typical shallow lake in east China, using multiple time series. Chlorophyll-a (Chl-a) concentration was used as a surrogate for algal (CyanoHABs: cyanobacterial harmful algal blooms) growth and the independent variables were total nitrogen (TN), total phosphorus (TP), and either water temperature or air temperature. The evaluation indicated that the model parameters could have distinctly different values, depending on whether or not constraints are imposed, time scales, and types of nutrients. The model performance varied in terms of time scales as well as magnitudes and fluctuations of Chl-a and TN or TP concentrations, achieving a relative better performance for the monthly rather than three-day time scale and for the central part rather than bays of the study lake. The model with TP as the independent variable had a better performance than the model with TN as the independent variable, regardless of the time scale used. The temperature-nutrient interactions were important for algal growth when the temporal fluctuations of these two factors were large but the interactions could become minimal otherwise