Overview of hybrid silica aerogel as biomaterial

Application of hydroxyapatite as a biomaterial in tissue engineering is challenging by its issue on stability. Hence, the capability of silica aerogel in improving the stability and biocompatibility of hydroxyapatite was proposed. Silica aerogel attracts much interest in various applications ranging from construction to medicine because of its excellent properties. This review summarizes the potential of hybrid silica aerogel in biomedical applications in regards to its different compositions. The review covers recent and previous studies on the hybrid silica aerogel, either organic or inorganic which are biocompatible to human cells. The future perspective focusing on the potential of hydroxyapatite incorporated silica aerogel as a biomaterial is also discussed here

Adsorptive removal of methylene blue and acid orange 7 by hexadecyltrimethylammonium bromide modified rice husk

The feasibility of rice husk (RRH) and surfactant modified rice husk (SMRH) to adsorb cationic dye, methylene blue (MB) and acid orange 7 (AO7) from aqueous solution was studied. SMRH was prepared by reacting RRH with different initial concentrations (1.0, 2.5 and 4.0 mM) of cationic surfactant quaternary ammonium compound, hexadecyltrimethylammonium bromide (HDTMABr). RRH and SMRH were characterized using Fourier transform infrared (FTIR) spectroscopy to determine surface functional group and effect of surfactant modification on the structure of RRH. Adsorption studies were performed in a series of batch experiment and effect of initial dye and HDTMABr concentrations on the adsorption capacity of RRH and SMRH were evaluated. The results showed that the removal of MB was higher for RRH compared to SMRH meanwhile AO7 removal was higher for SMRH compared to RRH. Modification of rice husk by cationic surfactant was proven to decrease the adsorption site for MB. On the other hand, the presence of surfactant on SMRH increased the adsorption site and allows more adsorption to occur for AO7. The equilibrium data were better described by Langmuir isotherm with maximum adsorption capacity for MB was 100.0 mg/g and 200.0 mg/g for AO7. In conclusion, the modification of rice husk by HDTMABr decreased the adsorption towards cationic dye but increased the adsorption towards anionic dye

Using feature selection as accuracy benchmarking in clinical data mining.

Automated prediction of new patients’ disease diagnosis based on data mining analysis on historical data is proven to be an extremely useful tool in the medical innovation. There are several studies focusing on this particular aspect. The objective of this study is two-fold. First, we look into three different classifiers, which are the Naïve Bayes, Multilayer Perceptron (MLP) and Decision Tree J48 to predict the diagnosis results. Next, we investigate the effects of feature selection in such experiments. We also compare the experimental results with the study of Comparative Disease Profile (CDP) using the same dataset. Results have shown that the Naive Bayes provides the best result in terms of accuracy in our experiments and in comparison with CDP. However, we suggest using Multilayer Perceptron since the variables used in our experiments are inter-dependent among each other. In addition, MLP has shown better accuracy than CDP

Adsorption of acid orange 7 by cetylpyridinium bromide modified sugarcane bagasse

In the present study, the adsorption of acid orange 7 (AO7) dye from aqueous solution by sugarcane bagasse (SB) and cetylpyridinium bromide (CPBr) modified sugarcane bagasse (SBC) was examined. SBC was prepared by reacting SB with different concentrations (0.1, 1.0 and 4.0 mM) of cationic surfactant, CPBr. The SB and SBC were characterized using Fourier transform infrared (FTIR) spectroscopy. The adsorption experiments were carried out in a batch mode. The effect of initial AO7 concentrations (5-1000 mg/L), initial CPBr concentrations and pH of AO7 solution (2-9) on the adsorption capacity of SB and SBC were investigated. The experimental adsorption data were analyzed using Langmuir and Freundlich isotherm models. The adsorption of AO7 onto SB and SBC followed Freundlich and Langmuir isotherm models, respectively. The maximum uptake of AO7 was obtained by SBC4.0 (SB treated with 4.0 mMCPBr) with the adsorption capacity of 144.928 mg/g. The highest AO7 removal was found to be at pH 2 and 7 for SB and SBC, respectively. As a conclusion, sugarcane bagasse modified with CPBr can become an alternative adsorbent for the removal of anionic compounds in aqueous solution

Preparation, characterization, and antibacterial activity of green-biosynthesised silver nanoparticles using Clinacanthus nutans extract

Plant leaf extract can be used as a reducing agent in the synthesis of silver nanoparticles (AgNP) in a green and safe way. As a result, this study describes the synthesis of AgNP using a Clinacanthus nutans plant extract. C. nutans is known as belalai gajah in Malaysia and is widely used as a medicinal herb. UV-Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and transmission electron microscope (TEM) were used to characterize the biosynthesized AgNP using C. nutans aqueous extract at pH 10, 70°C, and a reaction time of 48 hours. The UV-Vis spectra revealed a peak around 400 nm, while XRD confirmed AgNP's crystal structure, which had an average size of 20 to 30 nm, as shown in FESEM and TEM micrographs. The antibacterial activity of biosynthesized AgNP against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was tested using the disc diffusion technique (DDT). Antibacterial activity was limited against Enterococcus faecalis and methicillin-resistant Staphylococcus aureus (MRSA). AgNP, which was synthesized using C. nutans leaf extract AgNP as a bioreducing agent, has antibacterial activity against a wide range of bacteria in general

Enhanced normalization approach addressing stop-word complexity in compound-word schema labels

An extensive review of the existing schema matching approaches discovered an area of improvement in the field of semantic schema matching. Normalization and lexical annotation methods using WordNet have been somewhat successful in general cases. However, in the presence of stop-words these approaches result in poor accuracy. Stop-words have previously been ignored in most studies resulting in false negative conclusions. This paper proposes NORMSTOP (NORMalizer of schemata having STOP-words) as an improved schema normalization approach that addresses the complexity of stop-words (e.g. ‘by’, ‘at’, ‘and,’ or’) in Compound Word (CW) schema labels. Using a combined set of WordNet features, NORMSTOP isolates these labels during the preprocessing stage and resets the base-form to a relevant WordNet term, or an annotable compound noun. When tested on the same real dataset used in the earlier approach - (NORMS or NORMalizer of Schemata), NORMSTOP shows up to 13% improvement in annotation recall measurement. This level of improvement takes the overall schema matching process another step closer to perfect accuracy; while its absence exposes a gap in expectation, especially in today’s databases, where stop-words are in abundance

The design and development of peer-to-peer based mobile application for petty trading

Recent popularity of mobile devices such as smart phones and tablets have increase the usage of these devices including by petty traders. This paper presents a prototype mobile phone application designed and developed to enhance the business activities for petty traders especially in open markets such as night markets. The proposed application consists of three major component for petty trading activities: i)Trader Searching Component, ii)Trader- Customer Communication Component, and iii)Trader Pamphlet Distributor. Provided that both the trader and customer have installed the application on their phones the application will provide real-time information to the customer regarding nearest available traders doing their businesses at a particular trading place visited by the customer. It has to be noted that the application is based on decentralized peer-to-peer architecture in which there is no centralized party managing all the data

Synthesis and characterization of alcohol-free tyrosinase encapsulated silica aerogel

Encapsulation of tyrosinase enzyme into nanoporous silica aerogel via an alcohol-free colloidal sol-gel route using rice husk ash (RHA) as silica source was studied. Tyrosinase encapsulated silica aerogel (TESA) was synthesized with and without solvent extraction process at room temperature and neutral pH in order to study their effect on the enzyme activity and to minimize enzyme denaturation. The physicochemical properties of TESA was characterized by X-ray diffraction (XRD) technique, fourier transformed-infrared (FTIR) spectroscopy, field emission-scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). These characterizations confirmed tyrosinase in TESA was located inside the network of silica aerogel. Enzymatic activity of tyrosinase was assayed through the reduction of ascorbic acid using UV Visible spectrophotometer. Almost 98% of tyrosinase was successfully loaded into silica aerogel as determined by the leaching test of TESA. TESA without solvent extraction showed higher tyrosinase activity than TESA extracted by amyl acetate/acetone (v/v:1/1). The highest activities for both TESA were obtained with 10.00 mg/mL of enzyme loading that was aged for 2 days. The stability of tyrosinase in TESA was enhanced towards extreme temperature as well as acidic and basic conditions. Free tyrosinase was totally inactivated at pH 9 and at temperature exceeding 55 °C, while TESA showed a significant activity at these conditions. In the application of TESA, about 80% of phenol was removed after 3 hours contact with TESA. The reusability of tyrosinase in TESA was observed to be very high since TESA can be reused to remove phenol up to 10 times without significant loss. As a conclusion, nanoporous silica aerogel from RHA prepared with and without solvent extraction techniques can be used as suitable support for the improvement of the tyrosinase stability and it can be applied to remove phenol

Bionanotechnology: current progress in applied nanomaterials research

Bionanotechnology is a multidisciplinary fields involving nanotechnology for biological and medical applications. One of the area is applied nanomaterials such as biomaterial nanoparticles, adjuvant therapy for cancer, antibacterial agent and drug delivery system. Nanomaterials offer more advantages due to their smaller particles that exhibits higher performance and effectiveness of their application. In our recent progress of applied nanomaterials researches, several synthesized nanomaterials that we want to highlight are silica aerogels nanoparticles as biomaterial and zeolite NaY nanoparticles as adjuvant therapy for cancer. Both of them were synthesized from rice husk ash as silica source. We have found that the synthesized silica aerogels nanoparticles increased the viability and proliferation of normal human fibroblast cells in vitro as well as enhanced bioactivity in simulated body fluid after incorporated with hydroxyapatite. Thus, the hydroxyapatite incorporated silica aerogels nanoparticles could be used as a biomaterial or for wound healing. Whereas, the zeolite NaY nanoparticles had the ability to withstand gastrointestinal condition and good anticancer properties, making it a possible alternative adjuvant therapy for colorectal cancer. There are many researches can be performed in the area of bionanotechnology in the future such as biosynthesis of silver nanoparticles from plant (herbs) extract and synthesized zeolite nanoparticles from kaolin-clay loaded with silver ions as antibacterial agent. Research in the bionanotechnology field necessitate understanding and facilities of various disciplines including physical, analytical, inorganic and organic chemistry as well as biology and medical sciences, thus collaboration with various fields is encouraging to ensure the success of the research output

Semantic schema matching approaches: a review

An extensive review of the existing research work in the field of schema matching uncovers the significance of semantics in this subject. It is beyond doubt that both structural and semantics aspect of schema matching have been the topic of research for many years and there are strong references available for both. However, an in-depth analysis of all the available approaches suggests there are further scopes for improvement in the field of semantic schema matching. Normalization and lexical annotation methods using WordNet have been proposed in several studies, but the level of matching accuracy in those studies have not yet reached a point that can encourage full automation of schema matching in commercial use. This paper lists out several possible future work based on the existing limitations