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Integration process of fermentation and liquid biphasic flotation for lipase separation from Burkholderia cepacia
No full textLiquid Biphasic Flotation (LBF) is an advanced recovery method that has been effectively applied for biomolecules extraction. The objective of this investigation is to incorporate the fermentation and extraction process of lipase from Burkholderia cepacia using flotation system. Initial study was conducted to compare the performance of bacteria growth and lipase production using flotation and shaker system. From the results obtained, bacteria shows quicker growth and high lipase yield via flotation system. Integration process for lipase separation was investigated and the result showed high efficiency reaching 92.29% and yield of 95.73%. Upscaling of the flotation system exhibited consistent result with the lab-scale which are 89.53% efficiency and 93.82% yield. The combination of upstream and downstream processes in a single system enables the acceleration of product formation, improves the product yield and facilitates downstream processing. This integration system demonstrated its potential for biomolecules fermentation and separation that possibly open new opportunities for industrial production
Clinical outcomes of lithium disilicate single crowns after a mean duration of 3 years - A retrospective study
No full textPurpose: To investigate the clinical performance and clinical survival rate of lithium disilicate-based core ceramic (IPS e.max Press) utilised in single crowns and to the accompanying periodontal health status. Materials and Methods: A total of 47 patients with 88 IPS e.max Press single crowns were examined at the Faculty of Dentistry, University of Malaya, using modified United States Public Health Service evaluation criteria (USPHS). These 88 crowned teeth included 19 vital and 69 nonvital teeth that were restored with different post and core materials. The periodontal status was compared using the plaque index (PI), gingival recession (GR), modified papillary bleeding index (MPBI) and probing pocket depth (PPD) between the crowned teeth and contralateral control (sound) teeth. Results: About 96.6% of the crowns exhibited satisfactory clinical performance. The mean survival rate at three years was 97.7%, and 100% at two years with a low incidence of fractures. There were no staitistically significant differences in the mean gingival recession (p = 0.182) and mean plaque scores (p = 0.102) between crowned and control teeth. The crowned teeth had higher mean MPBI (p = 0.000) and PPD (p = 0.051) compared to the contralateral sound teeth. Periodontal response in relation to subgingival crown margins, was statistically significantly lower regarding pocket depths (p = 0.01) and bleeding on probing (p = 0.00). Conclusion: IPS e.max Press crowns exhibited satisfactory clinical performance with high survival rate. No dentinal sensitivity was recorded. Plaque retention and gingival recession were similar to contralateral control teeth. Poor periodontal health was related to the subgingival crown margins
Income Dependency on Non-timber Forest Products: An Empirical Evidence of the Indigenous People in Peninsular Malaysia
No full textThe indigenous people have been identified to be among the poorest and the most socioeconomically and culturally marginalized people all over the world. The main purpose of the paper is to explore the socioeconomic and demographic factors of indigenous people in Peninsular Malaysia in context of poverty and the role of income dependency of non-timber forest products (NTFP). The data were collected in 2014 and 2015 through primary and secondary sources. Partial least squares (PLS) method was used to analysis the data. PLS is a modeling technique that features multiple regression and principal component analysis. The study shows that still a large number of indigenous households is involved in the NTFP activities. But the communities are moving away from NTFP based income to cash-crop based income because of poor sustainable forest management and lack of forest property rights. However, NTFP have a significant role in the household income and contribute 24% of the average income. Moreover, the analysis shows that location is significant to the poverty. There should be a suitable sustainable forest management system which can teach these indigenous communities about proper way of NTFP gathering and given proper rights to forest land. Furthermore, education is not significant to indigenous people and there is a high rate of school dropout among them. The government should introduce a different education system for indigenous communities which will emphasize the importance of education to them
State of the art in passive digital image forgery detection: copy-move image forgery
No full textAuthenticating digital images is increasingly becoming important because digital images carry important information and due to their use in different areas such as courts of law as essential pieces of evidence. Nowadays, authenticating digital images is difficult because manipulating them has become easy as a result of powerful image processing software and human knowledge. The importance and relevance of digital image forensics has attracted various researchers to establish different techniques for detection in image forensics. The core category of image forensics is passive image forgery detection. One of the most important passive forgeries that affect the originality of the image is copy-move digital image forgery, which involves copying one part of the image onto another area of the same image. Various methods have been proposed to detect copy-move forgery that uses different types of transformations. The goal of this paper is to determine which copy-move forgery detection methods are best for different image attributes such as JPEG compression, scaling, rotation. The advantages and drawbacks of each method are also highlighted. Thus, the current state-of-the-art image forgery detection techniques are discussed along with their advantages and drawbacks
Bayesian approach to errors-in-variables in count data regression models with departures from normality and overdispersion
No full textIn most practical applications, the quality of count data is often compromised due to errors-in-variables (EIVs). In this paper, we apply Bayesian approach to reduce bias in estimating the parameters of count data regression models that have mismeasured independent variables. Furthermore, the exposure model is misspecified with a flexible distribution, hence our approach remains robust against any departures from normality in its true underlying exposure distribution. The proposed method is also useful in realistic situations as the variance of EIVs is estimated instead of assumed as known, in contrast with other methods of correcting bias especially in count data EIVs regression models. We conduct simulation studies on synthetic data sets using Markov chain Monte Carlo simulation techniques to investigate the performance of our approach. Our findings show that the flexible Bayesian approach is able to estimate the values of the true regression parameters consistently and accurately
Operational parameters effects on photocatalytic reactors of wastewater pollutant: a review
No full textThis study presents the operational parameters effects on photocatalytic degradation of liquid pollutants using titanium dioxide. Organic pollutants photodegradation is the most widely studied method, where photocatalysis is observed in many forms. Due to the cost efficiency of titanium dioxide as a photocatalyst, it has a greater role in this process as compared to other semiconductors. The operating parameters effects on photocatalytic degradation in wastewater pollutant using titanium dioxide based photocatalyst are presented in this paper. The findings are used to identify and explain the individual influence of different parameters, such as the photocatalyst composition, catalyst loading, initial pH, pollutant concentration, light intensity and temperature, on wastewater pollutants photocatalytic degradation. The successful application of laboratory scale techniques and the choice of treatment are generally dependent on the wastewater composition, however, much research is needed from the aspects of modelling and engineering design for a large scale operation. Besides that, a general overview of a prevailing trend in the use of titanium dioxide photocatalyst is presented with the emphasis placed on its achievements and problems
A recombinant subunit HS aba392 as a potential vaccine for haemorrhagic septicaemia disease in livestock
No full textHaemorrhagic septicaemia (HS) is a major disease in cattle and buffaloes, caused by certain serotypes of Pasteurella multocida, mainly B and E serotypes. Frequent HS outbreak has a major impact in many Asian countries, including Malaysia, where farmers encounter economic loss due to low milk production as well as death of their livestock. There are four types of vaccines available; broth bacterins, alum precipitated vaccine, aluminium hydroxide gel vaccine and oil adjuvant vaccine (OAV), but these vaccines can only provide short term immunity and therefore need to be administered annually. Hence, the development of a protein vaccine using recombinant antigen can be a potential candidate for the production of HS vaccine that would give longer immunity. We have successfully cloned the ABA392 gene fragment into a protein expression vector, pET-30a. The protein was expressed from our ABA392/pET30a clone and the immunogenicity of the protein has been tested on rats. This vaccine was able to trigger an immune response and therefore has the potential to be tested as suitable vaccine candidate in future studies. It is envisaged that this subunit vaccine will make a significant contribution in the management of HS among livestock in future
Correlates of viral suppression among HIV-infected men who have sex with men and transgender women in Lima, Peru
No full textIn Peru, HIV is concentrated among men who have sex with men (MSM) and transgender women (TGW). Between June 2015 and August 2016, 591 HIV-positive MSM and TGW were recruited at five clinical care sites in Lima, Peru. We found that 82.4% of the participants had achieved viral suppression (VS; VL < 200) and 73.6% had achieved maximal viral suppression (MVS; VL < 50). Multivariable modeling indicated that patients reporting transportation as a barrier to HIV care were less likely to achieve VS (aOR = 0.47; 95% CI = 0.30–0.75) and MVS (aOR = 0.56; 95% CI = 0.37–0.84). Alcohol use disorders were negatively associated with MVS (aOR = 0.62; 95% CI = 0.30–0.75) and age was positively associated with achieving MVS (aOR = 1.29; 95% CI = 1.04– 1.59). These findings underscore the need for more accessible HIV care with integrated behavioral health services in Lima, Peru
Bio-inspired for Features Optimization and Malware Detection
No full textThe leaking of sensitive data on Android mobile device poses a serious threat to users, and the unscrupulous attack violates the privacy of users. Therefore, an effective Android malware detection system is necessary. However, detecting the attack is challenging due to the similarity of the permissions in malware with those seen in benign applications. This paper aims to evaluate the effectiveness of the machine learning approach for detecting Android malware. In this paper, we applied the bio-inspired algorithm as a feature optimization approach for selecting reliable permission features that able to identify malware attacks. A static analysis technique with machine learning classifier is developed from the permission features noted in the Android mobile device for detecting the malware applications. This technique shows that the use of Android permissions is a potential feature for malware detection. The study compares the bio-inspired algorithm [particle swarm optimization (PSO)] and the evolutionary computation with information gain to find the best features optimization in selecting features. The features were optimized from 378 to 11 by using bio-inspired algorithm: particle swarm optimization (PSO). The evaluation utilizes 5000 Drebin malware samples and 3500 benign samples. In recognizing the Android malware, it appears that AdaBoost is able to achieve good detection accuracy with a true positive rate value of 95.6%, using Android permissions. The results show that particle swarm optimization (PSO) is the best feature optimization approach for selecting features
Agrobacterium-mediated gene delivery and transient expression in the red macroalga Chondrus crispus
No full textMolecular resources and transgenic studies in red algae are lagging behind those for green algae. The Agrobacterium-mediated gene-transfer method routinely used in plant transformation has not been fully utilised in the red algae, which, as an important source of phycocolloids, warrant more studies. In this regard, a stepwise methodology was developed for Agrobacterium-mediated transformation of the carrageenophyte Chondrus crispus using pCAMBIA 1301 and a construct featuring a codon-optimized beta-glucuronidase (GUS) reporter gene driven by the endogenous Chondrus actin promoter. The effects of several factors on transformation efficiency were investigated. An intimate association of Chondrus and bacterial cells was observed using scanning electron microscopy. GUS transient expression within Chondrus cortical and medullary cells with both expression cassettes testified to the amenability of Chondrus to Agrobacterium-mediated transformation. Darker staining, indicative of higher GUS activity, was observed with the Chondrus-specific construct, suggesting its superiority over the pCAMBIA 1301. Presence of acetosyringone, the wounding method and the type of co-cultivation medium significantly affected the transformation outcome and efficiency. The Agrobacterium-mediated transient expression presented here constitutes a first step towards tailoring a transformation strategy for Chondrus, which can serve to facilitate further transgenic studies in this important red alga