การศึกษาคุณสมบัติและการประยุกต์ใช้เปอร์ออกซิเดซจากใบยางพารา

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An Improvement of Content and Teaching Methods for Codes of Conduct and Ethics in Mass Communication Courses of Thailand’s Universities

This research examines the content about ethical issues in Thailand’s mass communication courses, teaching methods and guidelines for improving the content and teaching methods about codes of conduct cultivation. This research uses 3 methods in collecting data: content analysis of syllabus in mass communication courses, focus group of experts and in-depth interviews of instructors and professionals. The results show that most media courses emphasize every-day life and professional ethics. Their main content focuses on principles law and ethics which are taught by lecture in classes without any professional organizations’ collaboration. Most instructors and students do not aware of the significance of mass communication ethics’ courses. Guidelines for improving content and teaching methods which suggested by experts and instructors are: 1) collaborating of third parties—mass communication/professional organizations, institutions and enterprises 2) emphasizing practices in reallife situations/scenarios and discussions 3) training and adjusting instructors’ attitudes toward mass communication’s ethics including a role model 4) updating ethical courses’ content and interposing it in every course

Role of Surface Area, Primary Particle Size, and Crystal Phase on Titanium Dioxide Nanoparticle Dispersion Properties

Characterizing nanoparticle dispersions and understanding the effect of parameters that alter dispersion properties are important for both environmental applications and toxicity investigations. The role of particle surface area, primary particle size, and crystal phase on TiO2 nanoparticle dispersion properties is reported. Hydrodynamic size, zeta potential, and isoelectric point (IEP) of ten laboratory synthesized TiO2 samples, and one commercial Degussa TiO2 sample (P25) dispersed in different solutions were characterized. Solution ionic strength and pH affect titania dispersion properties. The effect of monovalent (NaCl) and divalent (MgCl2) inert electrolytes on dispersion properties was quantified through their contribution to ionic strength. Increasing titania particle surface area resulted in a decrease in solution pH. At fixed pH, increasing the particle surface area enhanced the collision frequency between particles and led to a higher degree of agglomeration. In addition to the synthesis method, TiO2 isoelectric point was found to be dependent on particle size. As anatase TiO2 primary particle size increased from 6 nm to 104 nm, its IEP decreased from 6.0 to 3.8 that also results in changes in dispersion zeta potential and hydrodynamic size. In contrast to particle size, TiO2 nanoparticle IEP was found to be insensitive to particle crystal structure

Molecular cloning and sequencing of a cDNA encoding 3-hydroxy -3-methylglutaryl coenzyme a synthase from hevea brasiliensis (HBK) mull arg

A 1.8 kb cDNA clone encoding 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase was isolated from a cDNA library prepared from the C-serum of rubber latex from Hevea brasiliensis (H.B.K.) Mull. Arg. using an Arabidopsis thaliana cDNA encoding HMG-CoA synthase as a probe. The nucleotide sequence analysis revealed an open reading frame of 1,392 nucleotides which encoded a protein of 464 amino acids with a predicted molecular mass of 51.28 kDa. The deduced amino acid sequence exhibits strong similarities with plant and mammalian HMG-CoA synthase sequences. Analysis of RNA samples from different tissues of rubber tree seedlings showed a higher mRNA level in stem and petiole than in leaves. In mature rubber trees there were higher mRNA levels in latex and petiole than in leaves. This suggests that the expression of the HMG-CoA synthase gene is higher in laticifer cells than in leaves. Genomic Southern blot analysis using the full-length cDNA as a probe indicates the presence of up to three HMG-CoA synthase genes in Hevea brasiliensis.Pluang Suwanmanee, Wallie Suvachittanont and Geoffrey B Finche