2,309 research outputs found
Biochemical Differentiation of Cocoa Cotyledon Proteins from Various Genetic Origins
Previous studies have reported that differences in the cocoa flavour of roasted
beans from various genetic origins do exist; however, the findings were mainly
based on sensory evaluation. In addition, the cocoa flavours differences were also
claimed to be solely due to the maternal plants and not to other factors such as
physiological factors. Cocoa cotyledon contains vicilin (7S)-class globulin (VCG), a
major storage protein. It is a native source of oligopeptides and free amino acids,
both of which have been identified as precursors of specific-cocoa aroma. These
precursors are formed by proteolysis during fermentation. The VCG and the
splitting specificity of proteases from cocoa cotyledons have been known to be
responsible in the production of cocoa-specific aroma precursors during
fermentation. The separation patterns of VCG which were separately isolated from
cocoa cotyledons of various genotypes namely Forastero, Criollo, Trinitario, PBC
140, SCA 12 and UITI are shown. Comparative studies of VCG patterns and its
multiple forms were conducted by means of SDS-PAGE and two-dimensional
electrophoresis (2-DIEF/SDS-PAGE), whereas oligopeptide profiles were detected using a high performance liquid chromatography. SDS-PAGE analysis of the
molecular weights of the predominant polypeptides of VCG subunits (47 and 31
kDa) from various genotypes did not show qualitative differences. The 2-D
IEF/SDS-PAGE analysis of the VCG subunits revealed at least 10 multiple forms
with pIs in the range of 6.1 to 6.8. The additional polypeptides with their multiple
forms which had pIs in the range of VCG subunits were also detected on 2-D
IEF/SDS-PAGE. These polypeptides were most probably the resultant degradation
proteolytic products from the action of aspartic endoprotease on VCG subunits.
There were very strong similarities in the VCG subunits and their degradation
products at the level of their polypeptide constituents from the standpoint of number,
molecular weight and isoelectric point. The oligopeptide profiles of autolysis
products of the acetone dry powder prepared from various genotypes did not
revealed differences. It indicates that the action of aspartic endoprotease of the
various cocoa genotypes on VCG during autolysis was similar. There was no
analytical identity difference of VCG subunits and their degradation proteolytic
products for all the genotypes. Thus, VCG seems not to be responsible for cocoa
aroma differences in cotyledons of the various genotypes within methodical limits.
The VCG was almost completely degraded as compared to the storage albumin at the
end of fermentation. In conclusion, aroma differences in raw cocoa harvested from
various genotypes are the result of other genotypes, physiological or curing related
factors but are not due to genetic differences of aroma precursors derived from
storage proteins
Exploring Classroom Management with Young Learners
This paper explores the definition of classroom management and establishes the author’s definition of classroom management and the underlying principles behind it. Thereafter, it examines some aspects of the author’s system of classroom management, specifically, the classroom as a Safe Space, behavior management, the teacher as a facilitator and the classroom environment. Finally, the paper concludes with an appeal to educators to reflect on their own classroom management practices and offers resources for those wishing to further explore the subject
Modelling stock selection in Malaysia based on Data Envelopment Analysis (DEA) / Md Khairu Amin Ismail
Stock selection has been a crucial puzzle to investors and abundant empirical works have looked at this issue. Nevertheless, there is very limited empirical evidence that employs DEA in stock selection. Therefore, the main purpose of the study is to apply DEA models on stock selection of Malaysian stocks. The scope of the study incorporates all firms of the five sectors of Bursa Malaysia Main Market, which are consumer, industrial, property, plantation, and trading & services. Two DEA models, technical-efficiency and super-efficiency, are utilized in modeling the DEA stock selection in Malaysia. Stock selection takes place during various economic conditions, specifically sideway-trend, upward-trend and downward-trend, covering from 1998 to 2005. The ex-post period of portfolio performance is evaluated based on 12-month (short-term) and 36-month (long-term) holding periods. The empirical findings show that, during sideway-trend selection, on average, both the DEA super-efficiency and technical-efficiency portfolios produce significantly positive abnormal returns over the long-term. However, during upward-trend selection, on average, the DEA super-efficiency portfolios exhibit significantly negative abnormal returns for both short-term and long-term periods. During downward-trend selection, the DEA super-efficiency portfolios show significantly negative abnormal returns over the long-term. The present study contributes to the literature by furnishing new empirical evidence on DEA stock selection literature as well as on the emerging market literature. Furthermore, it is also able to contribute to firms and policy makers as well. Overall, pertaining to the present findings, it is rendered that the DEA portfolios outperform over the long-term holding period particularly when the selection took place during side-way trend. This empirical finding suggests that the DEA models can be applied in Malaysia during side-way trend as a tool for helping investors in their stock selection
Lycopene content and lipophilic antioxidant capacity of by-products from Psidium guajava fruits produced during puree production industry.
The comparison of lycopene content and lipophilic antioxidant capacity was explored among pink guava fruit and by-products of its puree production industry namely refiner, siever and decanter. Lycopene content was measured using both UV–vis spectrophotometer and high performance liquid chromatography (HPLC) methods. Atmospheric pressure chemical ionization liquid chromatography–mass spectrometry (APCI-LC–MS) was applied in confirming the studied compound. Two assays were employed to determine the lipophilic antioxidant capacities namely lycopene equivalent antioxidant capacity (LEAC) and β-carotene bleaching assays. Lycopene content and antioxidant capacity were in the order of fruits > decanter > siever > refiner. Decanter exhibited the highest lycopene content and antioxidant among the studied by-products. It also gave a significant higher (p < 0.05) lycopene content than pink guava fruit based on the wet basis. There was a significant correlation between lycopene content and LEAC. All samples had a good antioxidant activity in β-carotene bleaching assay but negatively correlated to lycopene content. Decanter was found to be the highest in lycopene content (17 mg/100 g dry basis) and antioxidant capacity (22 μmol LE/100 g dry basis) among the by-products. This by-product of pink guava puree industry can be a potential source of lycopene and antioxidant compounds
Antioxidant Activity of Selected Commercial Seaweeds
This study aims to evaluate the antioxidant activity (total antioxidant and free radical scavenging activities) of seaweeds commercially available in the Malaysian supermarket. Four types of seaweeds namely Nori (Porphyra sp.), Kumbu (Laminaria sp.), Wakame (Undaria sp.) and Hijiki (Hijikia sp.) were used in the study. The extracts were prepared with water and ethanol, respectively. The β-carotene bleaching and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to determine antioxidant properties of seaweeds by measuring the decrease in absorbance at 470 and 517 nm. In water extract, Kumbu showed the highest total antioxidant activity of 63% compared with other samples. Kumbu, Nori and Hijiki exhibited higher radical scavenging activity than Wakame when extracted with water. Wakame exhibited the highest antioxidant and free radical scavenging activities in ethanolic extract with 58% and EC50 = 0.42 mg/ml respectively. The results of ANOVA analysis show significant differences (p<0.05) in the means of total antioxidant and free radical scavenging activities of the seaweeds. The results showed that processed commercial seaweeds exhibited varying degrees of antioxidant properties
Improving overall thermal transfer value of office tower building in Malaysia, case study : Ministry of Women Family and Community Development, Lot 4G11, Putrajaya / Azman Zainonabidin and Amirul Amin Ismail
This paper presents the Overall Thermal Transfer Value (OTTV) and the energy consumption of air-conditioned
office building in Malaysia. The study have been conducted to investigate the OTTV of Ministry of Women Family and Community Development’s office block at Lot 4G11, Putrajaya. OTTV calculation, energy consumption and effect of the building parameters on energy consumption have been investigated. OTTV formula in MS1525 and Green Building Index (GBI) rating tool have been used for the OTTV calculation. The study shown that the OTTV of the Lot 4G11 is more than 70W/m2. In order to comply with MS1525, where the minimum OTTV shall be less than 50W/m2, improvement of the building envelope have been proposed, and the OTTV have been reduced below 50W/m
2 . Since the Government has set that all government buildings in Putrajaya shall be GBI certified, further improvement of building envelope have been made in order to achieve OTTV for Platinum certification. It is found that improving the Window to Wall Ratio (WWR), Shading
Coefficient (SC) and U-value for glazing will further reduce the OTTV and improve the energy efficiency of the
Lot 4G11. Detailed calculations have been conducted to compare the results in between Building Baseline,
MS1525 and Platinum Design
A Review on The Inhibition Efficiency of Green Materials as a Potential Corrosion Protection on Ferrous and Non-Ferrous Metals in Various Environments
Green material is a beneficial material in combating corrosion on any metallic structure. Since it is a green material, hence it can be classified as an environmental friendly material. Environmental friendly material (eco-friendly) is the best material choice to be opted for corrosion mitigation. Eco-friendly materials produce no pollution to the environment, safe to be used because of organic materials, made from a waste product or a natural resource, cheap, wide range of availability, renewable resource, free of heavy metals and free of toxic compounds. Therefore, numerous research studies have been done worldwide by researchers as to study the effectiveness in term of inhibition efficiency of the eco-friendly material as corrosion mitigation method. This review highlighted a few eco-friendly materials such as rice husk, egg shell, banana peel and henna that have been tested successfully in the previous research studies as corrosion prevention method. Many of related and relevant research articles to this review topic have been included as to review the inhibition efficiency of the eco-friendly materials in corrosion mitigation. The result showed that the inhibition efficiency for all green materials reviewed was mainly above 90%. This showed that the green materials acted as a remarkable material either as a direct corrosion inhibitor or incorporated into a coating. The corrosion rate on metal was decreased as the molecules of green material being absorbed on the metal surface, creating a protective barrier and protected the metal surface from corrosion attack. This review provided the significant and valuable information regarding the application of eco-friendly material as corrosion mitigation because the facts in this review have indicated that the eco-friendly materials have an excellent inhibition efficiency for corrosion protection purpose on different metals in various environment
On extensions of nilpotent torsion rings by semisimple rings
A class of rings in which each member is the extension of a nilpotent torsion ring by a semisimple semiartinian ring is presented. © 1981, Australian Mathematical Society. All rights reserved
Shrimp trade competitiveness of Malaysia and selected ASEAN countries
This article investigates the level, composition, and sustainability of the trade competitiveness position of Malaysia among some of the world producers of shrimp commodities in Association of Southeast Asian Nations (ASEAN). The growth rate in the shrimp balance of trade (BOT) surplus had increased the most in Malaysia whereas Singapore recorded the highest growth rate in the shrimp BOT deficit. The trend of the relative trade advantage indices indicates that, among the ASEAN-5, Malaysia and Thailand maintained trade competitiveness in fresh shrimp while Indonesia remained competitive in exporting preserved shrimp. Further, the analytic hierarchy process exerts that Thailand possesses the highest competitiveness ranking in shrimp. To be as competitive as Thailand, Malaysia needs to develop a target area of concentration for shrimp production. This will help the government to introduce and implement policies to mitigate the alleged coastal destructions and environmental pollutions and to provide transparency in the shrimp supply chains
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