44 research outputs found
Fermentation optimization, purification and biochemical characterization of ι-carrageenase from marine bacterium Cellulophaga baltica
No full textOptimization of Fermentation Conditions for Carrageenase Production by <i>Cellulophaga</i> Species: A Comparative Study
No full textCarrageenases appear in various species of marine bacteria and are widely used for the degradation of carrageenans, the commercially significant sulphated polysaccharides. The carrageenase production ability of six different Cellulophaga species was identified, with ι-carrageenase being the most abundant carrageenolytic enzyme. C. algicola was the most potent strain, followed by C. fucicola and C. geojensis, whereas C. pacifica was the least effective carrageenase producer among the studied strains. The enzyme production was maximized using the one-factor-at-a-time optimization method. The optimal incubation temperature was identified as 25 °C and the incubation time was set as 48 h for all tested species. The optimal medium composition for Cellulophaga strains was determined as 30 g/L sea salt, 1.4 g/L furcellaran, and 3 g/L yeast extract. An ultrafiltered enzyme extracted from C. algicola had the highest activity at around 40 °C. The optimal pH for enzymatic degradation was determined as 7.8, and the enzyme was fairly stable at temperatures up to 40 °C
Design and development of rotating-sleeve refrigerant compressor
No full textA Single Vane Rotating Sleeve compression concept a patent of which has been filed by UTM, is the main focus of this study. Research and development on the concept was carried out to investigate its feasibility on a refrigeration system. The concept was designed based on the specifications of the existing reciprocating compressor installed in a refrigerator. In order to design a functional prototype, the author has conducted literature study on existing rotary compressor models such as rolling piston and sliding vane types that are used in room and car air conditioning systems respectively. The literature study is crucial in areas such as the geometrical optimization, material selection, tolerance and surface finishing in designing the prototype. Preliminary concept development and design are also conducted for the new concept investigating critical design data for used in future research. Further research and development however is needed to improve the compressor performance up to a commercial acceptable level
PERFORMANCE OF PULAU PANGKOR FIBREGLASS FISHING BOAT : PRELIMINARY DESIGN AND ANALYSIS
No full textFiberglass commonly known in the business as fiber reinforced plastic (FRP) or glass reinforced plastic (GRP) has been used in boat building for over 60 years. In that time, vessels of various categories have been built using FRP. Fishing boat is useful for people especially for transportation. It is not only transport as well as for fishing activities but also once become the main transportation for trade activities and to brings daily need for the villagers. As the used of fiberglass fishing boat nowadays keep increasing from day to day, hence this issue had bring consciousness to author to carry out this research not only to study the design trend of small FRP boat in the UNIKL MIMET research area but also to keep the data on all those boat’s samples so that the design can be preserve and become references for future designer
Determination of water quality and efficient removal of arsenic and iron from groundwater using mahogany fruit husk and banana peduncle charcoals
No full textThe groundwater (GW) of Bangladesh is predominantly contaminated with arsenic (As) and iron (Fe) which has a bad impact on human health. We tried to remove these elements with easily available mahogany-fruit (Swietenia mahagoni) husk charcoal (MHC) and banana (Musa acuminata) peduncle charcoal (BPC). The trial was implemented with 3 replications throughout the research. The sampled GW contained 0.06 mg As L−1 and 4.83 mg Fe L−1. Firstly, the pH was 3, 5, 7, and 9 with a 250 mg L−1 dose. The MHC removed almost 91.05 % of As at pH 5.0, and BPC removed almost 86.67 % of As at pH 9. However, in the case of Fe, the MHC removed almost 100 % at pH 7 and 9; and BPC removed the same quantity at pH 5, 7, and 9. Secondly, the contact times were 0, 5, 10, 20, and 40 min with a 250 mg L−1 dose at pH 7.0. The maximum removal of As and Fe was 100 % with MHC and BPC at 5 min. The pseudo-first-order kinetic, pseudo-second-order kinetic, and intra-particle diffusion models were considered. The result showed that the rate of adsorption followed the pseudo-second-order kinetic model. Lastly, the adsorbent doses were 0, 50, 150, 250, and 350 mg L−1. At pH 7, the highest removal of As was 79.47 % and Fe removal was 100 % at 350 mg L−1 dose for MHC. Similarly, the values were 79.29 % and 100 % for the same at 350 mg L−1 dose of BPC, indicating these charcoal are good for heavy metals removal
Independent, Rapid and Targeted Loss of Highly Repetitive DNA in Natural and Synthetic Allopolyploids of Nicotiana tabacum
No full textPMCID: PMC3351487This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Does OO sync with the way we think?
No full textGiven that corrective-maintenance costs already dominate the software life cycle and look set to increase significantly, reliability in the form of reducing such costs should be the most important software improvement goal. Yet the results are not promising when we review recent corrective-maintenance data for big systems in general and for OO in particular-possibly because of mismatches between the OO paradigm and how we think
Reduced graphene oxide/molecular imprinted polymer-organic thin film transistor for amino acid detection
No full textTop 100 most-cited publications on breast cancer and machine learning research:a bibliometric analysis
No full textBackground: Rapid advancement in computing technology and digital information leads to the possible use of machine learning on breast cancer. Objective: This study aimed to evaluate the research output of the top 100 publications and further identify a research theme of breast cancer and machine-learning studies. Methods: Databases of Scopus and Web of Science were used to extract the top 100 publications. These publications were filtered based on the total citation of each paper. Additionally, a bibliometric analysis was applied to the top 100 publications. Results: The top 100 publications were published between 1993 and 2019. The most productive author was Giger ML, and the top two institutions were the University of Chicago and the National University of Singapore. The most active countries were the USA, Germany, and China. Ten clusters were identified as both basic and specialised themes of breast cancer and machine learning. Conclusion: Various countries demonstrated comparable interest in breast cancer and machine-learning research. A few Asian countries, such as China, India and Singapore, were listed in the top 10 countries based on the total citation. Additionally, the use of deep learning and breast imaging data was trending in the past 10 years in the field of breast cancer and machine-learning research.</p
Biochemical Characteristics and Potential Biomedical Applications of Hydrolyzed Carrageenans
No full textSeaweed contains a variety of bioactive compounds; the most abundant of them are polysaccharides, which have significant biological and chemical importance. Although algal polysaccharides, especially the sulfated polysaccharides, have great potential in the pharmaceutical, medical and cosmeceutical sectors, the large molecular size often limits their industrial applications. The current study aims to determine the bioactivities of degraded red algal polysaccharides by several in vitro experiments. The molecular weight was determined by size-exclusion chromatography (SEC), and the structure was confirmed by FTIR and NMR. In comparison to the original furcellaran, the furcellaran with lower molecular weight had higher OH scavenging activities. The reduction in molecular weight of the sulfated polysaccharides resulted in a significant decrease in anticoagulant activities. Tyrosinase inhibition improved 2.5 times for hydrolyzed furcellaran. The alamarBlue assay was used to determine the effects of different Mw of furcellaran, κ-carrageenan and ι-carrageenan on the cell viability of RAW264.7, HDF and HaCaT cell lines. It was found that hydrolyzed κ-carrageenan and ι-carrageenan enhanced cell proliferation and improved wound healing, whereas hydrolyzed furcellaran did not affect cell proliferation in any of the cell lines. Nitric oxide (NO) production decreased sequentially as the Mw of the polysaccharides decreased, which indicates that hydrolyzed κ-Carrageenan, ι-carrageenan and furcellaran have the potential to treat inflammatory disease. These findings suggested that the bioactivities of polysaccharides were highly dependent on their Mw, and the hydrolyzed carrageenans could be used in new drug development as well as cosmeceutical applications
