Expression of Toll-like receptors 3, 7, 9 and cytokines in feline infectious peritonitis virus-infected CRFK cells and feline peripheral monocytes

Megat Hamzah Megat Mazhar Khair,Gayathri Thevi Selvarajah,Abdul Rahman Omar,Farina Mustaffa-Kamal 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.2

Background: The role of Toll-like receptors (TLRs) in a feline infectious peritonitis virus(FIPV) infection is not completely understood. Objectives: This study examined the expression of TLR3, TLR7, TLR9, tumor necrosis factoralpha(TNF-α), interferon (IFN)-β, and interleukin (IL)-10 upon an FIPV infection in Crandell-Reese feline kidney (CRFK) cells and feline monocytes. Methods: CRFK cells and monocytes from feline coronavirus (FCoV)-seronegative cats andFCoV-seropositive cats were infected with type II FIPV-79-1146. At four, 12, and 24 hours postinfection(hpi), the expression of TLR3, TLR7, TLR9, TNF-α, IFN-β, and IL-10, and the viralload were measured using reverse transcription quantitative polymerase chain reaction. Viralprotein production was confirmed using immunofluorescence. Results: FIPV-infected CRFK showed the upregulation of TLR9, TNF-α, and IFN-βexpression between 4 and 24 hpi. Uninfected monocytes from FCoV-seropositive cats showedlower TLR3 and TLR9 expression but higher TLR7 expression compared to uninfectedmonocytes from FCoV-seronegative cats. FIPV-infected monocytes from FCoV-seropositivecats downregulated TLR7 and TNF-α expression between 4 and 24 hpi, and 4 and 12 hpi,respectively. IFN-β was upregulated early in FIPV-infected monocytes from FCoV-seropositivecats, with a significant difference observed at 12 hpi compared to FCoV-seronegative cats. The viral load in the CRFK and FIPV-infected monocytes in both cohorts of cats was similarover time.ConclusionTLR7 may be the key TLR involved in evading the innate responseagainst inhibiting TNF-α production. Distinct TLR expression profiles between FCoVseronegativeand FCoV-seropositive cats were observed. The associated TLR that plays a rolein the induction of IFN-β needs to be explored further.

Wireless Machine-to-Machine Routing Protocol with Unidirectional Links

Megat Zuhairi,Haseeb Zafar,David Harle 한국산학기술학회 2011 SmartCR Vol.1 No.1

Wireless Machine-to-Machine (M2M) technology is a new approach to network communication that covers a wide area of applications. In this paper, we propose a reliable on-demand routing protocol for wireless M2M in Mobile Ad Hoc Network (MANET) applications such as telematics, healthcare devices, remote sensing for data mining, and building security monitoring systems. Generally, devices in such networks are typically battery powered and have wireless interfaces that could be connected to existing wireless infrastructures (e.g., IEEE 802.11) wireless networks. Devices on the network have different properties (i.e., transmission power) and thus communication may follow a sub-optimal path (i.e., asymmetrical path). We propose a reliable routing protocol that efficiently constructs a routing path in M2M with minimal route acquisition time and is capable of utilizing all possible link connectivity (i.e., unidirectional and bidirectional links). The performance differentials are investigated using NS-2. Our simulation results show that the proposed scheme achieves minimal end-to-end delay connection, higher goodput, and maximum reduction of normalized routing loads when compared with the competing Ad Hoc On-demand Distance Vector (AODV) routing protocol.

Dynamic Reverse Route for On-Demand Routing Protocol in MANET

( Megat Zuhairi ),( Haseeb Zafar ),( David Harle ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.5

successful connection between a pair of source and destination nodes. An efficient routing protocol constructs routing path with minimal time, less routing overhead and capable of utilizing all possible link connectivity. In general, most on-demand MANET routing protocols operates over symmetrical and bidirectional routing path, which is infeasible due to the inherent heterogeneous properties of wireless devices. Simulation results show that the presence of unidirectional links on a network severely affect the performance of a routing protocol. In this paper, a robust protocol independent scheme is proposed, which enable immediate rediscovery of alternative route for a path blocked by a unidirectional link. The proposed scheme is efficient; route rediscovery is locally computed, which results in significant minimization of multiple route packets flooding. Nodes may exploit route information of immediate neighbors using the local reply broadcast technique, which then redirect the control packets around the unidirectional links, therefore maintaining the end-to-end bidirectional connection. The proposed scheme along with Ad Hoc On-demand Distance Vector (AODV) and AODV-Blacklist routing protocol is investigated over three types of mobility models. Simulation results show that the proposed scheme is extremely reliable under poor network conditions and the route connectivity can be improved by as much as 75%.

Health-Seeking Behaviors and Treatments Received for Menopause Symptoms: A Questionnaire Survey among Midlife Women Attending Primary Healthcare Clinics in Malaysia

Anusha Manoharan,Megat Muhammad Haris Megat Zainal,Beh Hooi Chin,Koh Wen Ming,Zamzurina Asmuee,Norafini Salamon,Peter Jerampang,Nadia Hamimah Kamaludin,Chandrashekhar T Sreeramareddy 대한폐경학회 2023 대한폐경학회지 Vol.29 No.3

Objectives: This study aimed to assess menopause symptoms, treatment-seeking behaviors, treatments received, and factors associated with seeking consultation from healthcare providers (HCPs).Methods: Using a self-administered Menopause Quick-6 in the Malay language (MQ6[M]) questionnaire, we surveyed 349 women aged 40–60 years attending primary healthcare clinics in four states in Malaysia for their menopause symptoms. Health-seeking behaviors for menopause symptoms were assessed using questions regarding HCPs consulted and treatments prescribed. Binary logistic regression was employed on factors associated with seeking consultation for menopause symptoms.Results: Using MQ6(M), we observed that 125 (31.3%) women reported at least one menopause symptom, with joint pains (42.8%), menstrual changes (39.5%), and hot flashes (29.3%) being the most frequent symptoms. Furthermore, 60% of the women were prescribed vitamins, and only 13% were administered Hormone Replacement Therapy (HRT). Medical comorbidities, the presence of at least one gynecological condition, menopause status, and MQ6(M) score were associated with seeking consultation with an HCP. For women with medical conditions, the odds of seeking consultation increased by a factor of 1.34 (adjusted odds ratio [AOR], 1.34; 95% confidence interval [CI], 1.11–1.76) for every additional comorbidity. The odds of seeking consultation from an HCP increased by a factor of 1.26 (AOR, 1.26; 95% CI, 1.04–1.47) with a unit increase in MQ6(M) score.Conclusions: Most women had menopause symptoms but favored the use of complementary and alternative medicine over HRT. Screening and awareness of menopause treatments need to be improved at primary healthcare clinics.

Effect of alkaline activators on the fresh properties and strength of silico-manganese fume-slag activated mortar

Nasir, Muhammad,Johari, Megat Azmi Megat,Yusuf, Moruf Olalekan,Maslehuddin, Mohammed,Al-Harthi, Mamdouh A. Techno-Press 2020 Advances in concrete construction Vol.10 No.5

This study investigated the effect of alkaline activators - NaOH_aq (NH) (NH: 0-16 M) and Na₂SiO_3aq (NS) (NS/NH: 0-3.5) in the synthesis of silico-manganese fume (SMF) and ground blast furnace slag (BFS) blended alkali-activated mortar (AASB). The use of individual activator was ineffective in producing AASB of sufficient fresh and hardened properties, compared to the synergy of both activators. This may be attributed to incomplete dissolution and condensation of oligomers required for gelation of the binder. An inverse relationship was noted among the fresh properties and the NH concentration or NS/NH ratio. This was influenced by the dissolution and condensation of silicate monomers under polymerization process. The maximum 28-day strength of ~45 MPa, setting time of 60 min and flow of 182 mm was obtained with the use of combined activators (10M-NH and NS/NH=2.5). The combined activators at NS/10M-NH=2.5 constituted SiO₂/Na₂O, H₂O/Na₂O and H₂O/SiO₂ molar ratio of 1.61, 17.33 and 10.77, respectively. This facilitated the formation of C-S-H, C/K-A-S-H and C-Mn-S-H in the framework together with an increase in the crystallinity due to more silicate re-organization within the aluminosilicate chain. On comparison of the high concentrated with mild alkali synthesized product, it revealed that the concentration of OH^- and Si monomers together with alkali metals influenced the dissolution of precursors and embedment of the constituent elements in the polymeric matrix. These factors eventually contributed to the microstructural densification of the mortar prepared with NS/10M-NH=2.5 thereby enhancing the compressive strength.

Academic leadership capability framework: a comparison of its compatibility and applicability in Australia, New Zealand, and Malaysia

Majid Ghasemy,Sufean Hussin,Megat Ahmad Kamaluddin Megat Daud 서울대학교 교육연구소 2016 Asia Pacific Education Review Vol.17 No.2

Previous studies have shown that leadership capabilities and managerial competencies are related to leadership performance effectiveness, i.e., higher capabilities and competencies are associated with higher performance effectiveness, and vice versa. Among the studies focusing on these qualities in academic settings, two recent studies in Australia and New Zealand in 2008 and 2012 may be stated which were guided by a conceptual framework known as the Academic Leadership Capability Framework. This framework became the basis for the construction of a survey instrument in order to assess five vital components of university leadership. The framework and the survey instrument were employed for a similar study in Malaysian public and private universities. In performing descriptive analysis, the results of the three studies were compared. This analysis revealed interesting similarities and differences among academic leaders within the three countries which can be used as a base for further policy making, and characterizing effective leadership in higher education. In addition, inferential statistics techniques were employed to detect the impact of the University Type and Previous Experience outside higher education on capabilities, competencies, and performance of the Malaysian academic leaders.

Pivotal qualities for effective university leadership on the basis of a modified Australian model: the application of FIMIX-PLS and IPMA in the Malaysian academic context

Majid Ghasemy,Sufean Bin Hussin,Megat Ahmad Kamaluddin Bin Megat Daud,Ahmad Zabidi Bin Abdul Razak,Mohd Jamil Bin Maah 서울대학교 교육연구소 2017 Asia Pacific Education Review Vol.18 No.4

This study was undertaken to determine the extent to which leadership capabilities and managerial competencies explain leadership performance in Malaysian Higher Education context. Data were collected from academic leaders in 25 public and private universities and colleges using a few previously developed scales in Malaysian context. Next, the collected data through 368 surveys were screened thoroughly prior to the main analysis. A variance-based structural equation modeling approach was adopted and SmartPLS 3 was used to analyze the data, followed by running finite mixture segmentation and importance-performance map analysis. The results did disclose unobserved heterogeneity within the data. Through the study, two models namely low-current-tenure leaders and high-current-tenure leaders models were developed. Moreover, role-specific competency and change-oriented capability were identified as the major areas of improvement to be addressed by managerial activities based on low-current-tenure leaders and high-current-tenure leaders models, respectively.

Enhancement of Thermoelectric Properties in Cold Pressed Nickel Doped Bismuth Sulfide Compounds

Fitriani Fitriani,Suhana Mohd Said,Shaifulazuar Rozali,Mohd Faiz Mohd Salleh,Mohd Faizul Mohd Sabri,Duc Long Bui,Tadachika Nakayama,Ovik Raihan,Megat Muhammad Ikhsan Megat Hasnan,Mohamed Bashir Ali Ba 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.6

Nanostructured Ni doped Bi 2 S 3 (Bi 2−x Ni x S 3 , 0 ≤ x ≤ 0.07) is explored as a candidate for telluride free thermoelectric material,through a combination process of mechanical alloying with subsequent consolidation by cold pressing followed with asintering process. The cold pressing method was found to impact the thermoelectric properties in two ways: (1) introductionof the dopant atom in the interstitial sites of the crystal lattice which results in an increase in carrier concentration, and (2)introduction of a porous structure which reduces the thermal conductivity. The electrical resistivity of Bi 2 S 3 was decreasedby adding Ni atoms, which shows a minimum value of 2.35 × 10 −3 Ω m at 300 °C for Bi 1.99 Ni 0.01 S 3 sample. The presenceof porous structures gives a signifi cant eff ect on reduction of thermal conductivity, by a reduction of ~ 59.6% compared toa high density Bi 2 S 3 . The thermal conductivity of Bi 2−x Ni x S 3 ranges from 0.31 to 0.52 W/m K in the temperature range of27 °C (RT) to 300 °C with the lowest κ values of Bi 2 S 3 compared to the previous works. A maximum ZT value of 0.13 at300 °C was achieved for Bi 1.99 Ni 0.01 S 3 sample, which is about 2.6 times higher than (0.05) of Bi 2 S 3 sample. This work showan optimization pathway to improve thermoelectric performance of Bi 2 S 3 through Ni doping and introduction of porosity.

Influence of palm oil fuel ash on behaviour of green high-performance fine-grained cement mortar

Sagr, Salem Giuma Ibrahim,Johari, M.A. Megat,Mijarsh, M.J.A. Techno-Press 2022 Advances in materials research Vol.11 No.2

In the recent years, the use of agricultural waste in green cement mortar and concrete production has attracted considerable attention because of potential saving in the large areas of landfills and potential enhancement on the performance of mortar. In this research, microparticles of palm oil fuel ash (POFA) obtained from a multistage thermal and mechanical treatment processes of raw POFA originating from palm oil mill was utilized as a pozzolanic material to produce high-performance cement mortar (HPCM). POFA was used as a partial replacement material to ordinary Portland cement (OPC) at replacement levels of 0, 5, 10, 15, 20, 25, 30, 35, 40% by volume. Sand with particle size smaller than 300 ㎛ was used to enhance the performance of the HPCM. The HPCM mixes were tested for workability, compressive strength, ultrasonic pulse velocity (UPV), porosity and absorption. The results portray that the incorporation of micro POFA in HPCMs led to a slight reduction in the compressive strength. At 40% replacement level, the compressive strength was 87.4 MPa at 28 days which is suitable for many high strength applications. Although adding POFA to the cement mixtures harmed the absorption and porosity, those properties were very low at 3.4% and 11.5% respectively at a 40% POFA replacement ratio and after 28 days of curing. The HPCM mixtures containing POFA exhibited greater increase in strength and UPV as well as greater reduction in absorption and porosity than the control OPC mortar from 7 to 28 days of curing age, as a result of the pozzolanic reaction of POFA. Micro POFA with finely graded sand resulted in a dense and high strength cement mortar due to the pozzolanic reaction and increased packing effect. Therefore, it is demonstrated that the POFA could be used with high replacement ratios as a pozzolanic material to produce HPCM.

Preservation of Coagulation Efficiency of Moringa oleifera, a Natural Coagulant

S. Katayon,S. C. Ng,M. M. N. Megat Johari,L. A. Abdul Ghani 한국생물공학회 2006 Biotechnology and Bioprocess Engineering Vol.11 No.6

In recent years, there has been an interest to use Moringa oleifera as the natural coagulant due to cost, associated health and environmental concerns of synthetic organic polymers and inorganic chemicals. However, it is known that M. oleifera as the natural coagulant is highly biodegradable and has a very short shelf life. This research was carried out to investigate the effects of storage temperature, packaging methods, and freeze-drying on the preservation of M. oleifera seeds powders. Non freeze-dried M. oleifera was prepared into different packaging namely open container, closed container and vacuum packing, whilst, freeze-dried M. oleifera was stored in closed container and vacuum packing. Each of the packaging was stored at room temperature (30 to 3℃) and refrigerator (4℃). The turbidity removal efficiencies of stored M. oleifera were examined using jar test at monthly interval for 12 months. The results indicated that non freeze-dried M. oleifera kept in the refrigerator (4℃) would preserve its coagulation efficiency. In addition, closed container and vacuum packing were found to be more appropriate for the preservation of non freeze-dried M. oleifera, compared to open container. Freeze-dried M. oleifera retained its high coagulation efficiency regardless the storage temperature and packaging method for up to 11 months. Besides, higher increment in zeta potential values for water coagulated with freeze-dried M. oleifera indicated the higher frequency of charge neutralization and better coagulation efficiency of freeze-dried M. oleifera, compared to non freeze-dried seeds. As a coagulant, M. oleifera did not affect the pH of the water after treatment.