Processing and thermal properties of composites based on recycled PET,sisal fibers,and renewable plasticizers

This investigation focuses on the preparation of bio‐based composites from recycled poly (ethylene terephthalate) (PET) and sisal fibers (3 cm, 15 wt %), via thermopressing process. Plasticizers derived from renewable raw materials are used, namely, glycerol, tributyl citrate (TBC) and castor oil (CO), to decrease the melting point of the recycled PET (T_m ∼ 265°C), which is sufficiently high to initiate the thermal decomposition of the lignocellulosic fiber. All used materials are characterized by thermogravimetric analysis and differential scanning calorimetry, and the composites are also characterized via dynamic mechanical thermal analysis. The storage modulus (30°C) and the tan δ peak values of CT [PET/sisal/TBC] indicate that TBC also acts as a compatibilizing agent at the interface fiber/PET, as well as a plasticizer. To compare different processing methods, rheometry/thermopressing and compression molding are used to prepare the recycled PET/sisal/glycerol/CO composites. These two different methods of processing show no significant influence on the thermal properties of these composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40386.     

Neural Crest-Derived Stem Cells (NCSCs) Obtained from Dental-Related Stem Cells (DRSCs): A Literature Review on Current Knowledge and Directions toward Translational Applications

Evidence from dental-related stem cells (DRSCs) suggests an enhanced potential for ectodermal lineage differentiation due to their neural crest origin. Growing evidence that DRSC cultures can produce cells with a neural crest-derived stem cell (NCSC)-like phenotype supports their potential for future therapeutic approaches for neurodegenerative diseases and nerve injuries. However, most of the evidence is limited to the characterization of DRSCs as NCSCs by detecting the expression of neural crest markers. Only a few studies have provided proof of concept of an improved neuro-glial differentiation or direct applicability in relevant models. In addition, a current problem is that several of the existing protocols do not meet manufacturing standards for transferability to a clinical scenario. This review describes the current protocols to obtain NCSCs from DRSCs and their characterization. Also, it provides important considerations from previous work where DRSCs were established and characterized as mesenchymal stromal cells but studied for their neuro-glial differentiation potential. The therapeutic advancement of DRSCs would depend on establishing protocols that can yield a neural crest-like phenotype efficiently, using appropriate manufacturing standards and testing them in relevant models of disease or injury. Achieving these conditions could then facilitate and validate the therapeutic potential of DRSC-NCSCs in regenerative therapies.     

Solid Tumors and Kinase Inhibition: Management and Therapy Efficacy Evolution

The increasing numbers of cancer cases worldwide and the exceedingly high mortality rates of some tumor subtypes raise the question about if the current protocols for cancer management are effective and what has been done to improve upon oncologic patients’ prognoses. The traditional chemo-immunotherapy options for cancer treatment focus on the use of cytotoxic agents that are able to overcome neoplastic clones’ survival mechanisms and induce apoptosis, as well as on the ability to capacitate the host’s immune system to hinder the continuous growth of malignant cells. The need to avert the highly toxic profiles of conventional chemo-immunotherapy and to overcome the emerging cases of tumor multidrug resistance has fueled a growing interest in the field of precision medicine and targeted molecular therapies in the last couple of decades, although relatively new alternatives in oncologic practices, the increased specificity, and the positive clinical outcomes achieved through targeted molecular therapies have already consolidated them as promising prospects for the future of cancer management. In recent years, the development and application of targeted drugs as tyrosine kinase inhibitors have enabled cancer treatment to enter the era of specificity. In addition, the combined use of targeted therapy, immunotherapy, and traditional chemotherapy has innovated the standard treatment for many malignancies, bringing new light to patients with recurrent tumors. This article comprises a series of clinical trials that, in the past 5 years, utilized kinase inhibitors (KIs) as a monotherapy or in combination with other cytotoxic agents to treat patients afflicted with solid tumors. The results, with varying degrees of efficacy, are reported.     

Ozone Application for the Improvement of UASB Reactor Effluent I. Physical-Chemical and Biological Appraisal

Ozonation can improve the effluent characteristics of UASB (upflow anaerobic sludge blanket) reactors treating domestic sewage, by removing organic matter, solids, surfactants, color and microorganisms. In Brazil, part of the effluent of a 120 msup3; UASB reactor, fed with screened domestic sewage at an hydraulic retention time of 7 hours, was post-treated in a two-column ozonation system of 300 liters total volume. With a contact time of 50 minutes and ozone application dosage of 16.7 mg/L, the following removals were obtained at the ozonation step: 51‰ BOD, 56‰COD, 76‰ TSS, 62‰ color, and 91‰ surfactants. Pathogens and indicator organisms were inactivated to over 99.9‰. Ozonation completely destroyed Salmonella, protozoa cysts and helminth eggs and larvae.     

Microscopic diagnosis of the leaf and stem of Piper solmsianum C.DC

Piper solmsianum C.DC., which is popularly known as pariparoba, is a shrub that measures 1–3 m in height and it inhabits areas with wet tropical soils. The objective of this study was to analyze the leaf and stem anatomy using light microscopy, scanning electron micrographs, and energy‐dispersive X‐ray spectroscopy in order to provide information for species identification. The anatomical profile showed the following main microscopic markers: hypostomatic leaf; hypodermis layer on both sides; pearl glands; biconvex midrib shape; five collateral vascular bundles in open arc with the central bundle larger than the others; circular stem shape; collateral vascular bundles arranged in two rings; sinuous sclerenchymatic sheath in the pith; secretory idioblasts; and starch grains in the mesophyll, in the ground parenchyma of the midrib, petiole, and in the stem; and six morphotypes of calcium oxalate crystals (styloids, cuneiform, tabular crystal rosettes, cuneiform crystal rosettes, elongated square dipyramids, as well as very elongated square dipyramids).     

Smith predictor based-sliding mode controller for integrating processes with elevated deadtime

An approach to control integrating processes with elevated deadtime using a Smith predictor sliding mode controller is presented. A PID sliding surface and an integrating first-order plus deadtime model have been used to synthesize the controller. Since the performance of existing controllers with a Smith predictor decrease in the presence of modeling errors, this paper presents a simple approach to combining the Smith predictor with the sliding mode concept, which is a proven, simple, and robust procedure. The proposed scheme has a set of tuning equations as a function of the characteristic parameters of the model. For implementation of our proposed approach, computer based industrial controllers that execute PID algorithms can be used. The performance and robustness of the proposed controller are compared with the Matausek-Mici? scheme for linear systems using simulations.     

Diminished macrophage cholesterol removal rate by the altered HDL metabolism in the Nagase analbuminemic rat

Dyslipoproteinemia of the Nagase analbuminemic rat (NAR) is characterized by elevated concentrations of VLDL and LDL attributed to increased rates of liver lipoprotein synthesis. Increased lysophosphatidylcholine (LPC) in NAR HDL has been attributed to high plasma LCAT activity. We show here that, as compared with Sprague-Dawley rats (SDR), NAR plasma triacylglycerol (TAG), total cholesterol (TC), HDL TAG, protein, total phospholipids (PL), LPC, and PS are increased. These alterations rendered the NAR HDL particle more susceptible to the activity of the enzyme hepatic lipoprotein lipase (HL), which otherwise was unaltered in our study. Fractional catabolic rates in blood of the autologous ¹²⁵I-apoHDL (median and lower quartile values), were, respectively, 0.231 and 1.645 (n=10) in NAR as compared with 0.140 and 0.109 (n=10) in SDR (P=0.012), corresponding to synthesis rates of HDL protein of 89.8±33.7 mg/d in NAR and 17.4±6.5 mg/d in SDR (P=0.0122). Furthermore, Swiss mouse macrophage free-cholesterol (FC) efflux rates, measured as the percent [¹⁴C]-cholesterol efflux/6 h, were 8.2±2.3 (n=9) in NAR HDL and 11.2±3.2 (n=10) in SDR HDL (P=0.03). Therefore, in NAR the modification of the HDL composition slows down the cell FC efflux rate, and together with the increased rate of plasma HDL metabolism influences the reverse cholesterol transport system.