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Fulltext A railway rescheduling model with priority setting

Shuib, A., Alwadood, Z.

Pertanika Journal of Science & Technology, 2017;25(2):649-660.
MyJurnal

This paper presents a mathematical approach to solve railway rescheduling problems. The approach assumes that the trains are able to resume their journey after a given time frame of disruption whereby The train that experiences disruption and trains affected by the incident are rescheduled. The approach employed mathematical model to prioritise certain types of train according the railway operator’s requirement. A pre-emptive goal programming model was adapted to find an optimal solution that satisfies the operational constraints and the company’s stated goals. Initially, the model minimises the total service delay of all trains while adhering to the minimum headway requirement and track capacity. Subsequently, it maximises the train service reliability by only considering the trains with delay time window of five minutes or less. The model uses MATLAB R2014a software which automatically generates the optimal solution of the problem based on the input matrix of constraints. An experiment with three incident scenarios on a double-track railway of local network was conducted to evaluate the performance of the proposed model. The new provisional timetable was produced in short computing time and the model was able to prioritise desired train schedule.
Fulltext A goal programming model for portfolio optimisation problem in fuzzy environment

Mokhtar, M., Shuib, A., Mohamad, D.

Pertanika Journal of Science & Technology, 2017;25(2):593-606.
MyJurnal

Portfolio optimisation is one of the most crucial issues in investment decision-making and has received considerable attention from researchers and practitioners. Traditionally, the portfolio optimisation models are formulated based on the assumption that investors have complete information on the distribution of random returns. However, in real life case, this is not possible since decisions have to be made under uncertainty. This paper deals with a fuzzy portfolio optimisation problem in which returns and turnover rates of securities are represented by fuzzy variables. A goal programming model is proposed to optimise three objectives: maximisation of portfolio return, maximisation of liquidity and minimisation of the portfolio risk. The cardinality constraints, floor and ceiling constraints are also taken into consideration. Finally, a numerical experiment using real data is conducted to demonstrate the applicability of the model.
Neuraminidase treatment abrogates the binding abnormality of IgA1 from IgA nephropathy patients and the differential charge distribution of its alpha-heavy chains

Hashim OH, Shuib AS, Chua CT

Nephron, 2001 Dec;89(4):422-5.
PMID: 11721160

We have studied the interaction of the Gal-GalNAc-reactive champedak lectin-C with neuraminidase-treated and untreated IgA1 from IgA nephropathy patients. The binding ability of the lectin to untreated IgA1 from IgA nephropathy patients was significantly lower as compared to the untreated IgA1 from normal controls. This differential lectin-binding capacity was abrogated when the experiment was performed on neuraminidase-treated sera. Treatment of the serum IgA1 with neuraminidase also abrogated the differential charge distribution between the alpha-heavy chains of IgA nephropathy patients and normal controls.
Sera of IgA nephropathy patients contain a heterogeneous population of relatively cationic alpha-heavy chains

Shuib AS, Chua CT, Hashim OH

Nephron, 1998;78(3):290-5.
PMID: 9546689

Sera of IgA nephropathy (IgAN) patients and normal subjects were analysed by two-dimensional (2-D) gel electrophoresis. Densitometric analysis of the 2-D gels of IgAN patients and normal subjects revealed that their protein maps were comparable. There was no shift of pI values in the major alpha-heavy chain spots. However, the volume of the alpha-heavy chain bands were differently distributed. Distribution was significantly lower at the anionic region in IgAN patients (mean anionic:cationic ratio of 1.184 +/- 0.311) as compared to normal healthy controls (mean anionic:cationic ratio of 2.139 +/- 0.538). Our data are in support of the previously reported findings that IgA1 of IgAN patients were lacking in sialic acid residues.
The application of Artocarpus integer seed lectin-M in the detection and isolation of selective human serum acute-phase proteins and immunoglobulins

Hashim OH, Ahmad F, Shuib AS

Immunol Invest, 2001 May;30(2):131-41.
PMID: 11465670

Champedak (Artocarpus integer) lectin-M is a lectin with high specificity and affinity for the core-mannosyl residues of the N-linked oligosaccharides of glycoproteins. We have studied the interaction of the champedak seed lectin with human serum glycoproteins that were resolved by 2-dimensional (2-D) gel electrophoresis. The lectin demonstrated strong interaction with haptoglobin beta chain, orosomucoid, alpha1-antitrypsin, alpha2-HS glycoprotein, transferrin, hemopexin, alpha1B-glycoprotein, and the heavy chains of IgA, IgM and IgG of the human serum. With exceptions of the heavy chains of the immunoglobulins and alpha1B-glycoprotein, all the other lectin-M-probed glycopeptides are acute-phase proteins. The use of champedak lectin-M to probe for serum glycoproteins that were separated in a 2-D gel electrophoresis and Western blotting technique may be conveniently applied to analyse the acute-phase and humoral immune responses simultaneously. Subjecting human serum to immobilised-lectin-M affinity chromatography was able to isolate intact haptoglobin, alpha1-antitrypsin, alpha1B-glycoprotein, hemopexin and IgA.
The interaction of selective plant lectins with neuraminidase-treated and untreated IgA1 from the sera of IgA nephropathy patients

Hashim OH, Shuib AS, Chua CT

Immunol Invest, 2001 Feb;30(1):21-31.
PMID: 11419909

A study on the binding interaction of lectins from Artocarpus heterophyllus (jacalin), Glycine max and Sambucus nigra with standardised quantity of IgA from the IgA nephropathy patients and normal controls was performed. The Glycine max lectin demonstrated higher affinity towards the serum IgA of IgAN patients as compared to normal controls. However, the affinity binding was lower in cases ofjacalin and the Sambucus nigra lectin. When serum samples were treated with neuraminidase, the differential jacalin affinity binding between IgA1 of patients and normal controls was abrogated. Our data are in support of the view that the O-linked oligosaccharide moieties of the patients IgA1 were generally lacking in galactose and sialic acid residues.
The effects of piper sarmentosum water extract on the expression and activity of 11β-hydroxysteroid dehydrogenase type 1 in the bones with excessive glucocorticoids

Suhana Mohd Ramli E, Nirwana Soelaiman I, Othman F, Ahmad F, Nazrun Shuib A, Mohamed N, et al.

Iran J Med Sci, 2012 Mar;37(1):39-46.
PMID: 23115429

BACKGROUND: Long-term glucocorticoid therapy causes secondary osteoporosis leading to pathological fractures. Glucocorticoid action in bone is dependant upon the activity of 11β-hydroxysteroid dehydrogenase type 1 enzyme (11β-HSD1). Piper sarmentosum is a local herb that possesses the ability to inhibit 11-βHSD1 enzyme activity. We aimed to determine the effects of Piper sarmentosum water extract on 11-βHSD1 expressions and activity in the bones of glucocorticoid-treated adrenalectomized rats.
METHODS: Forty male Sprague-Dawley rats (200-250 g) were used. Twenty-four animals were adrenalectomized and received intramuscular injection of dexamethasone (120 μg/kg/day). They were simultaneously administered with either Piper sarmentosum water extract (125 mg/kg/day), GCA (120 mg/kg/day) or distilled water as vehicle by oral gavage for two months. Eight animals were sham-operated and given vehicle daily, i.e. intramuscular olive oil and oral distilled water.
RESULTS: Following two months treatment, dexamethasone-treated adrenalectomized rats had significantly lower 11β-HSD1 dehydrogenase activity and higher 11β-HSD1 expression in the femoral bones compared to the sham-operated and baseline group. The rats supplemented with Piper sarmentosum water extract had significantly higher 11β-HSD1 dehydrogenase activity and lower 11β-HSD1 expression in the bones.
CONCLUSION: The results showed that Piper sarmentosum water extract had the ability to prevent glucocorcoticoid excess in the bones of glucocorticoid-treated adrenalectomized rats through the local modulation of 11β-HSD1 expression and activity, and may be used as prophylaxis for osteoporosis in patients on long-term glucocorticoid treatment.