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Publication Title : Effects of extracts from Phyllanthus watsonii Airy Shaw on cell apoptosis in cultured human breast cancer MCF-7 cells.
Author : Associate Prof. Dr. Nurhayati Binti Zainal Abidin
Dr. Sugumaran A/L Manickam
Prof. Datin Dr. Norhanom Binti Abdul Wahab
Publisher URL : www.elsevier.de/etp

Publication Abstract:
Species of Phyllanthus have traditionally been used for hundreds of years for treating many ailmentsincluding diabetes, anemia,bronchitis and hepatitis. The present study aims to investigate the cytotoxic and apoptotic effects of methanol (PWM), hexane (PWH) and ethyl acetate (PWE) extracts from the leaves of the endemic plant Phyllanthus watsonii Airy Shaw (Phyllanthaceae) on MCF-7 human breast cancer cells. We observed that the PWM, PWH and PWE extracts were cytotoxic and selectively inhibited the growth and proliferation of MCF-7 cells compared to untreated control in a dose dependent manner with an IC50 of 12.7±4.65, 7.9±0.60 and 7.7±0.29 g/ml, respectively. However, the extracts were not toxic at these concentrations to normal human lung fibroblast MRC-5 cells. Cell death induced by PWM, PWH and PWE extracts were mainly due to apoptosis which was characterized by apoptotic morphological changes and a nuclear DNA fragmentation. Caspase-3 activation following P. watsonii extracts treatment was also evident for apoptotic cell death which was preceded by an S phase cell cycle perturbation. The results suggested that the cytotoxic activity of P. watsonii extracts was related to an early event of cell cycle perturbation and a later event of apoptosis. Hence, P. watsonii displays potential to be further exploited in the discovery and development of new anticancer agents.

Publication Title : Massive Mitochondrial Gene Transfer in a Parasitic Flowering Plant Clade
Author : Dr. Sugumaran A/L Manickam
Publisher URL : www.plosgenetics.org

Publication Abstract:
Recent studies have suggested that plant genomes have undergone potentially rampant horizontal gene transfer (HGT), especially in the mitochondrial genome. Parasitic plants have provided the strongest evidence of HGT, which appears to be facilitated by the intimate physical association between the parasites and their hosts. A recent phylogenomic study demonstrated that in the holoparasite Rafflesia cantleyi (Rafflesiaceae), whose close relatives possess the world’s largest flowers, about 2.1% of nuclear gene transcripts were likely acquired from its obligate host. Here, we used next-generation sequencing to obtain the 38 protein-coding and ribosomal RNA genes common to the mitochondrial genomes of angiosperms from R. cantleyi and five additional species, including two of its closest relatives and two host species. Strikingly, our phylogenetic analyses conservatively indicate that 24%–41% of these gene sequences show evidence of HGT in Rafflesiaceae, depending on the species. Most of these transgenic sequences possess intact reading frames and are actively transcribed, indicating that they are potentially functional. Additionally, some of these transgenes maintain synteny with their donor and recipient lineages, suggesting that native genes have likely been displaced via homologous recombination. Our study is the first to comprehensively assess the magnitude of HGT in plants involving a genome (i.e.,mitochondria) and a species interaction (i.e., parasitism) where it has been hypothesized to be potentially rampant. Our results establish for the first time that, although the magnitude of HGT involving nuclear genes is appreciable in these parasitic plants, HGT involving mitochondrial genes is substantially higher. This may represent a more general pattern for other parasitic plant clades and perhaps more broadly for angiosperms.

Publication Title : A Bilingual Child's Acquisition of Mandarin and English: Same or Different Rate?
Author : Associate Prof. Dr. Kuang Ching Hei
Publisher URL : - none -

Publication Abstract:
This paper is descriptive in nature. It looks at the utterances of one Malaysian-Chinese bilingual child who was specifically spoken to in Mandarin and English from birth. The aim of this paper is to highlight the different speech components present in the two languages. There is some evidence to show that the child's preferred language is not necessarily the dominant language. The child was observed closely by the researcher cum mother over a period of seven months. Initial utterances were tape recorded but later discarded due to impracticality. Subsequent utterances were then spontaneously recorded into journals as and when they occurred within the child’s home with details such as time, date, place and participants indicated. Transcribed orthographically, data were then categorized according to the languages heard and then the speech components (see Hoff, 2009; Foster-Cohen, 1999; Crystal, 1997) respectively. A frequency count of all these utterances suggests that 59% of the child’s utterances were in English while 19% were in Mandarin (dominant language) with smaller percentages subscribing to the various environmental languages. Data also indicate that more nouns were used in English and but slightly more verbs and noun phrases were used in Mandarin. This phenomenon was also used as a determinant to gauge the rate of acquisition of the two languages. A very small percentage of the child’s data were also articulated as complete sentences but this was done in mixed languages, which could be a typical phenomenon of bilingual language acquisition at the early stage.

Publication Title : Application of genetic algorithm in optimization of unified power flow controller parameters and its location in the power system network.
Author : Prof. Dr. Mahmoud Moghavvemi
Publisher URL : http://www.sciencedirect.com/science/article/pii/S0142061512005741

Publication Abstract:
Abstract This work demonstrates the application of Genetic Algorithm (GA) technique for the simultaneous stabilization of power systems using a Unified Power Flow Controller (UPFC). The GA is applied to find the optimal location of the UPFC and to tune its control parameters under different operating conditions. The problem is formulated as a multiobjective optimization problem which aims at maximizing the damping ratio of the electromechanical modes using different lines fitted with the UPFC. The approach is successfully tested on the 16-machine 68-bus New England–New York interconnected system and on the Iraqi National Super Grid System (INSGS) to validate its effectiveness in the damping of local and inter-area modes of oscillations. In addition, the proposed approach demonstrated better performance when compared to a fuzzy-based UPFC damping controller.

Publication Title : Stress Management Skills and University Students� Academic Behaviour: A Case Study
Author : Associate Prof. Dr. Shukeri Bin Mohamad
Mr. Mohamad Azrien Bin Mohamed Adnan
Publisher URL : - none -

Publication Abstract:
There are various potential stressors that students face on a daily basis. These include the challenge of properly adjusting to the campus life, which is quite different from their home environments. Lifestyle change is quite challenging. The more life changes an individual experiences, the more the stress the individual faces and the more likely it is that illness and disease will result. This study explored the stress management skills and academic behaviour of undergraduate students. Data was collected based on the observation and interviews. The respondents were selected from the University of Daar El-Salam Gontor Ponorogo Indonesia. Data was analysed based on the transcriptions. By using qualitative method, the data analysis revealed that stress management skills and academic behaviour has positive mainstream. It was recommended that stress management skills training should be given prominence in universities’ guidance programmes, while concerned authorities should endeavour to provide facilities that may help to reduce academic stress.

Featured Abstract :  1032
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