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Fulltext The important role of concurrent engineering in product development process

Hambali, A., Sapuan, S.M., Ismail, N., Nukman, Y., Abdul Karim, M.S.

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

Nowadays, Concurrent Engineering (CE) is becoming more important as companies compete in the worldwide market. Reduced time in product development process, higher product quality, lower cost in manufacturing process and fulfilment of customers’ requirements are the key factors to determine the success of a company. To produce excellent products, the concept of Concurrent Engineering must be implemented. Concurrent Engineering is a systematic approach which can be achieved when all design activities are integrated and executed in a parallel manner. The CE approach has radically changed the method used in product development process in many companies. Thus, this paper reviews the basic principles and tools of Concurrent Engineering and discusses how to employ them. Similarly, to ensure a product development process in the CE environment to run smoothly and efficiently, some modifications of the existing product development processes are proposed; these should start from market investigation to detail design.
The reliability and process capability assessment of suspended growth sewage treatment plant in Melaka, Malaysia

Ishak A, Mohamad E, Hambali A, Johari NL

Water Sci Technol, 2022 Nov;86(9):2233-2247.
PMID: 36378177 DOI: 10.2166/wst.2022.360

This paper presents the promising method of synchronizing the Six Sigma and reliability analyses at 15 sewage treatment plants (STPs) operating in Melaka, Malaysia. Five different suspended growth treatment technologies in various capacities were investigated. The sequential batch reactor (SBR) and extended aeration activated sludge (EAAS) processes, conventional activated sludge (CAS), aerated lagoon (AL), and oxidation pond (OP) were compared using innovative Niku's treatment reliability and Six Sigma process capability method for biological oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids (TSS), oil and grease (O&G), and ammoniacal nitrogen (NH3-N) effluent parameters and justified the importance of understanding the lognormal behavior of the effluent parameters in interpreting the performance monitoring results and discharge compliance. The results showed that the SBR and EAAS systems relatively fulfilled the highest performance (>95%) compared to conventional systems to ensure the high quality of effluent discharge. Although the whole system is incapable of removing nutrients efficiently, ranging between 42.31% and 90.48%, may lead to eutrophication issues. Process modification and treatment control should become a critical priority in order to reduce variability, improve stability, and increase the efficiency of nutrient removal. These initiatives promote global sustainable development goals (SDGs) 2030 and the domestic water sector transformation (WST) 2040 by treatment cost reduction, improving environmental sustainability and guaranteeing social and health benefits.
Doses to patients in routine X-ray examinations in Malaysia

Ng KH, Rassiah P, Wang HB, Hambali AS, Muthuvellu P, Lee HP

Br J Radiol, 1998 Jun;71(846):654-60.
PMID: 9849390

A collaborative national survey initiated by the University of Malaya and the Ministry of Health was conducted from 1993 to 1995 to establish baseline patient dose data for seven common types (12 projections) of X-ray examinations in Malaysia. A total of 12 randomly selected public hospitals and 867 patients were included in this survey. The entrance surface doses (ESD) received by the patients were measured using thermoluminescent dosemeters (TLDs) attached to the patient's skin. Histograms are presented showing wide, positively skewed distributions of measured entrance surface doses for each examination. Mean, median, first and third quartile values of ESD and median effective dose are reported. Survey results are generally comparable with those reported in the UK, USA and by the International Atomic Energy Agency (IAEA). The results also provide information on dose level for a lower weight population (mean weight 60 kg) compared with the international reference dose values based on a 70 kg standard. The findings support the importance of the on-going national quality assurance programme to ensure doses are kept to a level consistent with optimum image quality. The data will also be useful for the formulation of national guidance levels as recommended by the IAEA. Furthermore, this study provides patient dosimetry information on healthcare level II countries.
Fulltext Is cerebral small vessel disease a central nervous system interstitial fluidopathy?

Abdul Hamid H, Hambali A, Okon U, Che Mohd Nassir CMN, Mehat MZ, Norazit A, et al.

IBRO Neurosci Rep, 2024 Jun;16:98-105.
PMID: 39007087 DOI: 10.1016/j.ibneur.2023.12.004

A typical anatomical congregate and functionally distinct multicellular cerebrovascular dynamic confer diverse blood-brain barrier (BBB) and microstructural permeabilities to conserve the health of brain parenchymal and its microenvironment. This equanimity presupposes the glymphatic system that governs the flow and clearance of metabolic waste and interstitial fluids (ISF) through venous circulation. Following the introduction of glymphatic system concept, various studies have been carried out on cerebrospinal fluid (CSF) and ISF dynamics. These studies reported that the onset of multiple diseases can be attributed to impairment in the glymphatic system, which is newly referred as central nervous system (CNS) interstitial fluidopathy. One such condition includes cerebral small vessel disease (CSVD) with poorly understood pathomechanisms. CSVD is an umbrella term to describe a chronic progressive disorder affecting the brain microvasculature (or microcirculation) involving small penetrating vessels that supply cerebral white and deep gray matter. This review article proposes CSVD as a form of "CNS interstitial fluidopathy". Linking CNS interstitial fluidopathy with CSVD will open a better insight pertaining to the perivascular space fluid dynamics in CSVD pathophysiology. This may lead to the development of treatment and therapeutic strategies to ameliorate the pathology and adverse effect of CSVD.
Fulltext Hypoxia-Induced Neuroinflammation in Alzheimer's Disease: Potential Neuroprotective Effects of Centella asiatica

Hambali A, Kumar J, Hashim NFM, Maniam S, Mehat MZ, Cheema MS, et al.

Front Physiol, 2021;12:712317.
PMID: 34721056 DOI: 10.3389/fphys.2021.712317

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterised by the presence of extracellular beta-amyloid fibrillary plaques and intraneuronal neurofibrillary tau tangles in the brain. Recurring failures of drug candidates targeting these pathways have prompted research in AD multifactorial pathogenesis, including the role of neuroinflammation. Triggered by various factors, such as hypoxia, neuroinflammation is strongly linked to AD susceptibility and/or progression to dementia. Chronic hypoxia induces neuroinflammation by activating microglia, the resident immune cells in the brain, along with an increased in reactive oxygen species and pro-inflammatory cytokines, features that are common to many degenerative central nervous system (CNS) disorders. Hence, interests are emerging on therapeutic agents and plant derivatives for AD that target the hypoxia-neuroinflammation pathway. Centella asiatica is one of the natural products reported to show neuroprotective effects in various models of CNS diseases. Here, we review the complex hypoxia-induced neuroinflammation in the pathogenesis of AD and the potential application of Centella asiatica as a therapeutic agent in AD or dementia.
The Standardized Extract of Centella asiatica and Its Fractions Exert Antioxidative and Anti-Neuroinflammatory Effects on Microglial Cells and Regulate the Nrf2/HO-1 Signaling Pathway

Hambali A, Jusril NA, Md Hashim NF, Abd Manan N, Adam SK, Mehat MZ, et al.

J Alzheimers Dis, 2024;99(s1):S119-S138.
PMID: 38250772 DOI: 10.3233/JAD-230875

BACKGROUND: Neuroinflammation and oxidative stress can aggravate the progression of Alzheimer's disease (AD). Centella asiatica has been traditionally consumed for memory and cognition. The triterpenes (asiaticoside, madecassoside, asiatic acid, madecassic acid) have been standardized in the ethanolic extract of Centella asiatica (SECA). The bioactivity of the triterpenes in different solvent polarities of SECA is still unknown.
OBJECTIVE: In this study, the antioxidative and anti-neuroinflammatory effects of SECA and its fractions were explored on lipopolysaccharides (LPS)-induced microglial cells.
METHODS: HPLC measured the four triterpenes in SECA and its fractions. SECA and its fractions were tested for cytotoxicity on microglial cells using MTT assay. NO, pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), ROS, and MDA (lipid peroxidation) produced by LPS-induced microglial cells were measured by colorimetric assays and ELISA. Nrf2 and HO-1 protein expressions were measured using western blotting.
RESULTS: The SECA and its fractions were non-toxic to BV2 microglial cells at tested concentrations. The levels of NO, TNF-α, IL-6, ROS, and lipid peroxidation in LPS-induced BV2 microglial cells were significantly reduced (p