A quadratic Bézier representation withholds a curve segment with free from loops, cusps and inflection points. Furthermore,
this rational form provides extra freedom to generate visually pleasing curves due to the existence of weights. In this
paper, we propose sufficient conditions for rational quadratic Bézier curves to possess monotonic increasing/decreasing
curvatures by means of monotone curvature tests which are based on the derivative of curvature functions. We have
derived a simple interval of the middle weight that assures the construction of a family of rational quadratic Bézier curves
to be planar spirals, which is characterized by the turning angle, end curvatures and the chords of control polygon.
The proposed formulation can be used by CAD systems for aesthetic product design, highway/railway design and robot
trajectory design avoiding unwanted curvature oscillations.
The development of an efficient tissue culture protocol for somatic embryo would facilitate the genetic modification in
breeding program. The present study describes the reproducible protocols for three wetland Malaysian rice cultivars
(MR232, MR220 and MR220-CL2) and upland rice (Bario) via somatic embryogenesis. In the present study, four preheat treatments (35, 40, 45 and 50°C) were applied to mature seeds with different imbibition periods (3, 5 and 7 days)
prior to culture on MS media with 3 mg/L 2,4-D. The results showed that the cultivars exhibited the highest callus
induction percentage from 45°C pre-heated seeds and 3 days imbibition (100%, 96%, 100% and 95% for MR232, MR220,
MR220-CL2 and Bario, respectively). Callus was induced early ranging from 3 to 12 days compared to without pre-heat
treatment. The regeneration efficiency for MR220 and MR220-CL2 cultivars was significantly higher compared to the
control treatment. However, both 45°C and 25°C (control) treatments produced higher plantlet regeneration for MR232
and Bario. This study observed that pre-heat treated seeds prior to callus induction did promote callusing and hence
regeneration. These findings can be used to establish a suitable protocol for the in vitro regeneration system for several
genetic improvements in the numerous stress tolerances of Malaysian rice.
The use of honey as a therapeutic agent dates back at 8000 years and has markedly increased interest into its potential
health benefits. The by-products of the flower nectar have a complex chemical composition which promotes benefits in
underlying mechanism of human diseases. Malaysian Tualang Honey (MTH) is a multifloral jungle honey produced by
the rock bee (Apis dorsata). This review consolidates the results of carious studies involving biochemical assays of tissue
culture and animal trials of anti-cancer properties of MTH. Often studied in the context of breast cancer cell lines, MTH
has promising data for possible mechanisms in anti-cancer activity. These include apoptosis via depolarization of the
mitochondrial membrane, caspase-dependent apoptosis, reduction of angiogenesis and the promotion of cell cycle arrest
without posing cytotoxic effect on normal cell lines. Despite positive outcomes in tissue cultures, the oral administration
of MTH in breast cancer animal models showed slower tumour progression, reduction in tumour size and better grading
of histological features. The alleviation of breast carcinogenesis via modulation of hematologic, estrogenic and apoptotic
activities promotes MTH as a promising anticancer agent. With confidence in a conclusion that MTH is a useful treatment
for cancer, further experimental and clinical studies should be conducted.
Spore-forming bacteria, Bacillus sp., frequently been associated with the contamination of rice and other starchy
products. Spores are more resistant to antimicrobial treatments than its vegetative cells. The extract of Indonesian bay
leaf (Syzygium polyanthum L.) was assessed for its antibacterial and sporicidal activities against vegetative cells and
spores of B. cereus isolated from rice (25 strains). The results showed that S. polyanthum L. extract was able to inhibit
the growth of vegetative cells of all B. cereus isolates with MICs ranged from 0.16 to 0.63 mg/mL and can kill with
MBCs ranged from 0.31 to 2.50 mg/mL. The bactericidal endpoint for B. cereus BC-NP.8 in time kill curve was at 1.25
mg/mL (8× MIC) after 4 h of incubation while for B. cereus ATCC 33019 was at 2.50 mg/mL (8× MIC). The sporicidal
activity of S. polyanthum L. extract was not affected by different temperatures treatment and alteration of the pHs of
extract. Therefore, this indicates that the extract was stable after exposed to pH3, 7 and 10 as well as temperature
of 50, 80, and 121°C. Observation under on scanning electron microscope the structure of the B. cereus ATCC 33019
spores was ruptured after being treated with 1% (w/v) S. polyanthum L. extract for 1 h. In conclusion, S. polyanthum L.
extract had antibacterial and sporicidal activity against vegetative cells and spores of B. cereus isolated from rice.
Semakan semula litostratigrafi Formasi Singa dilakukan berdasarkan data-data baru yang diperoleh melalui kajian
terbaru. Secara umumnya, Formasi Singa dominan dengan batu lumpur hitam yang berselang lapis dengan batu pasir
nipis hingga sederhana tebal serta sedikit lapisan konglomerat. Kajian melibatkan analisis terhadap beberapa log
sedimen yang telah direkodkan di lapangan. Kesemua log sedimen tersebut telah dikorelasikan untuk mendapatkan satu
log komposit yang mewakili keseluruhan Formasi Singa. Berdasarkan kajian terperinci korelasi litologi yang dilakukan,
cadangan litostratigrafi baru Formasi Singa mengandungi empat ahli iaitu Ahli Kentut, Ahli Ular, Ahli Selang dan Ahli
Lembung. Ahli Kentut merupakan ahli yang paling tua diikuti dengan Ahli Ular, Ahli Selang dan Ahli Lembung. Ahli
Ular di dalam Formasi Singa dianggap sebagai satu unit kekanta antara Ahli Kentut dengan Ahli Selang. Beberapa
siri perubahan paras laut ditafsirkan sepanjang pengendapan batuan Formasi Singa dipercayai akibat daripada proses
pencairan glasier yang menyebabkan paras laut meningkat dan pengendapan berterusan yang menyebabkan lembangan
menjadi cetek dan paras laut menjadi rendah.
Ultra-high temperature is a process that involves heating of milk to a very high temperature to produce sterile milk products.
However, food poisoning due to consumption of UHT milk still happen in Malaysia. This study was done to develop a
film that is made by poly(L-lactic acid) (PLLA) to detect the presence of microorganisms in UHT milk products. UHT milk
that was used in this study was full cream milk. Contaminated milk that contained Bacillus cereus was made to conduct
a model system on the relationship between colony forming unit of microorganisms and contact angle. Contaminated
milk was also used as a control sample to study the difference of milk properties between fresh and contaminated milk.
Physicochemical analysis (Brix, colour, pH and contact angle) and microbiological analysis (total plate count) were
done to UHT milk sample as soon as the packaging of the milk was unsealed. Analysis was done with 30 min time interval
until 4 h and 30 min since the unsealing of packaging. The results showed that presence of microorganisms in UHT milk
was detected after the milk product was unsealed and exposed to environment for 3 h and 30 min. Contact angle resulted
from the presence of microorganisms in UHT milk was 64.34 - 65.44° with its colony forming unit, 2.1 – 3.9 cfu/mL.
Therefore, the potential usage of contact angle on PLLA thin film with respect to colony forming unit (cfu) in detecting
the presence of microorganisms in UHT milk product was attained and well modelled.
In this paper, we develop algebraic order conditions for two-point block hybrid method up to order five using the approach
of B-series. Based on the order conditions, we derive fifth order two-point block explicit hybrid method for solving
special second order ordinary differential equations (ODEs), where the existing explicit hybrid method of order five is
used to be the method at the first point. The method is then trigonometrically fitted so that it can be suitable for solving
highly oscillatory problems arising from special second order ODEs. The new trigonometrically-fitted block method is
tested using a set of oscillatory problems over a very large interval. Numerical results clearly showed the superiority
of the method in terms of accuracy and execution time compared to other existing methods in the scientific literature.
Kajian terhadap elektrolit polimer berasaskan 49% poli(metil metakrilat) cangkukan getah asli (MG49) dengan
natrium iodida (NaI) dalam aplikasi sel suria terpeka pewarna (DSSC) telah dijalankan. Kesan kepekatan garam
ke atas sifat elektrokimia, morfologi, kimia dan kehabluran MG49-NaI telah dianalisis menggunakan spektroskopi
impedan elektrokimia (EIS), mikroskopi imbasan elektron (SEM), spektroskopi inframerah transformasi Fourier (FTIR)
dan pembelauan sinar-X (XRD). Morfologi keratan rentas menunjukkan struktur membran berliang mikro dan homogen.
Nilai kekonduksian ion tertinggi pada suhu bilik bagi membran elektrolit polimer MG49-NaI pada penambahan 30 %
bt. garam NaI adalah 8.86 × 10-5 S cm-1. Analisis inframerah menunjukkan interaksi antara atom oksigen dengan ion
natrium berlaku pada kumpulan berfungsi eter (C–O–C) dan karbonil (C=O). Sifat kehabluran MG49-NaI polimer
elektrolit didapati berkurang dengan peningkatan kepekatan garam. Analisis kronoamperometri memberikan nilai
nombor pindahan ion (tion) sebanyak 0.92 membuktikan elektrolit polimer MG49-NaI (30 % bt.) adalah pengkonduksi
jenis ion. Ujian prestasi DSSC keadaan pepejal bagi FTO/TiO2
-N719/MG49-NaI (30 % bt.)/I2
/Pt sampel telah memberikan
keputusan kecekapan setinggi 0.26% dengan prestasi fotovoltaik, Jsc, Voc dan ff masing-masing adalah 1.30 mA cm-2, 0.56
V dan 34.91. Membran dalam keadaan pepejal-kuasi atau separa pepejal memberikan nilai kecekapan 3.48 % dengan
nilai Voc = 0.75 V, Jsc = 12.71 mA cm-2 dan FF = 37.70.
In this study, the effects of suction and injection on the mixed convection flow of a nanofluid, over a moving permeable
vertical plate were discussed. A similarity variable was used to transform the governing equations to the ordinary
differential equations, which were then solved numerically using the bvp4c programme from MATLAB. Dual solutions
(upper and lower branches) were found within a certain range of the mixed convection parameter in assisting and
opposing flow regions. A stability analysis was implemented to confirm that the upper branch solution was stable, while
the lower branch solution was unstable.
The application of the Variance Targeting Estimator (VTE) is considered in GJR-GARCH(1,1) model, under three
misspecification scenarios, which are, model misspecification, initial parameters misspecification and innovation
distribution assumption misspecification. A simulation study has been performed to evaluate the performance of VTE
compared to commonly used, which is the Quasi Maximum Likelihood Estimator (QMLE). The data has been simulated
under GJR-GARCH(1,1) process with initial parameters ω = 0.1, α = 0.05, β = 0.85, γ = 0.1 and an innovation with a
true normal distribution. Three misspecification innovation assumptions, which are normal distribution, Student-t
distribution and the GED distribution have been used. Meanwhile, for the misspecified initial parameters, the first initial
parameters have been setup as ω = 1, α = 0, β = 0 and γ = 0. Furthermore, the application of VTE as an estimator has
also been evaluated under real data sets and three selected indices, which are the FTSE Bursa Malaysia Kuala Lumpur
Index (FBMKLCI), the Singapore Straits Time Index (STI) and the Jakarta Composite Index (JCI). Based on the results, VTE
has performed very well compared to QMLE under both simulation and the applications of real data sets, which can be
considered as an alternative estimator when performing GARCH model, especially the GJR-GARCH.
Natural rubber (NR) latex gloves are widely used as a very important barrier for healthcare workers. However, they
can still be perforated easily by sharp devices and instruments. The aim of this study was to investigate the effect of the
addition of graphene oxide (GO) to low-ammonia NR latex on its puncture resistance, mechanical properties and thermal
stability. GO was synthesized using modified Hummers’ reaction. The produced GO was mixed into the NR latex solution at
various doses (0.01-1.0 wt. %), followed by a coagulant dipping process using ceramic plates to produce film samples.
Puncture resistance was enhanced by 12% with 1.0 wt. % GO/NR. Also, the incorporation of GO improved the stress at
300% and 500%, the modulus at 300% and 500% and the tear strength of low-ammonia NR latex films.
Basal stem rot disease of oil palm caused by Ganoderma boninense is one of the most devastating diseases in oil palm
plantation resulting in low yield, loss of palm stands and shorter replanting cycle. To-date, there is no effective treatment
for Ganoderma infected palms. Control measures, either chemical or cultural approaches, show varying degrees of
effectiveness. The application of biological control agents which is environmental-friendly could be an attractive solution
to overcome the problem. Earlier, we had isolated a mycoparasite, Scytalidium parasiticum, from the basidiomata of
Ganoderma boninense. In vitro assay and nursery experiment showed that this fungus could suppress Ganoderma infection
and reduce disease severity. However, metabolites which might contribute to the antagonistic or mycoparasitic effect
remain unknown. In the current study, optimization of fungal sample processing, extraction, and analytical procedures
were conducted to obtain metabolites from the maize substrate colonized by mycoparasitic ascomycetous Scytalidium
parasiticum. This technique capable of producing sexual spores in sac-like organs. Untargeted metabolomics profiling
was carried out by using Liquid Chromatography Time of Flight Mass Spectrometry (LC-ToF-MS). We found that
S. parasiticum in both liquid- and solid-state cultivation gave higher metabolite when extracted with 60% methanol with
1% formic acid in combination with homogenisation methods such as ultrasonication and grinding. The findings from
this study are useful for optimisation of metabolite extraction from other fungi-Ganoderma-plant interactions.
In this study oil palm empty fruit bunches (EFB) fibres was used to synthesize biophenolic resin (BPR) at a different
formaldehyde/liquefied empty fruit bunches (F/LEFB) molar ratio which is 1.0, 1.5 and 2.0. The higher molar ratio of F/
LEFB used has resulted in an increased of viscosity and solid content of BPR resin. The first decomposition of BPR resin
occured around 86 to 130°C due to the evaporation of low molecular weight substance which were water, free phenol
and formaldehyde. Glass fibre reinforced biophenolic composite (BPC) and glass fibre reinforced biophenolic elastomer
composite (BPEC) was successfully fabricated using BPR resin. The impact strength and flexural strain of BPEC were
higher than that of BPC. The impact strength of BPEC 1.5 was the highest at 47.71 kJm-2. However, the flexural strength
of BPEC was lower compared with BPC, which the highest flexural strength was obtained by BPC 1.0 at 65.18 MPa. The
cross-sectional image from scanning electron microscope (SEM) of BPEC and BPC confirmed the presence of epoxidized
natural rubber (ENR) improved the compatibility between glass fibre and BPR resin.
Nepenthes, locally known as ‘periuk kera’ in Malaysia, is a fascinating species due to uniqueness in their morphology
in having pitcher organ for carnivorous diet. The pitcher plant has been used for cooking traditional delicacies and
as traditional remedies to treat illness. Hence, this species might possess beneficial health properties. This study
aimed to compare the antioxidant activity of the pitcher extracts from Nepenthes ampullaria, Nepenthes rafflesiana
and their hybrid, Nepenthes × hookeriana. The samples were extracted using methanol:chloroform:water (3:1:1)
via sonication assisted extraction and the extracts were subjected to three different antioxidant assays, namely
2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP) and total phenolic content (TPC). Extract from N.
ampullaria exhibited the strongest radical scavenging activity (0.148 ± 0.04 mg/mL) with the highest ferric reducing
power (0.009 ± 0.003 mg GA/mg dry weight) among the three species, whereas that of N. rafflesiana possessed the
highest phenolic content (0.057 ± 0.017 mg GA/mg dry weight). However, the antioxidant capacities of the pitcher
extracts were not significantly different (p>0.05) between the three species and were much lower than the gallic acid
as a standard reference.
Tropical peat swamp forest (PSF) is one of the most endangered ecosystems in the world. However, the impacts of
anthropogenic activities in PSF and its conversion area towards fish biodiversity are less understood. This study
investigates the influences of water physico-chemical parameters on fish occurrences in peat swamp, paddy field and
oil palm plantation in the North Selangor peat swamp forest (NSPSF), Selangor, Malaysia. Fish and water samples were
collected from four sites located in the peat swamps, while two sites were located in the paddy field and oil palm plantation
areas. Multivariate analyses were used to determine the associations between water qualities and fish occurrences in
the three habitats. A total of 1,382 individual fish, belonging to 10 families, 15 genera and 20 species were collected.
The family Cyprinidae had the highest representatives, followed by Bagridae and Osphronemidae. The most abundant
species was Barbonymus schwanefeldii (Bleeker 1854), while the least abundant was Wallago leerii Bleeker, 1851. The
paddy field and oil palm plantation area recorded significantly higher fish diversity and richness relative to peat swamp
(p<0.05). The water physico-chemical parameters, such as pH, DO, NH3
-N, PO4, SO4
, and Cl2 showed no significant
difference between paddy field and oil palm plantation (p>0.05), but was significantly different from the peat swamp
(p<0.05). However, no water quality parameter was consistently observed to be associated with fish occurrences in all
of the three habitats, but water temperature, NH3
-N, Cl2, SO4
, and EC were at least associated with fish occurrences in
two habitats studied. This study confirmed that each habitat possess different water quality parameters associated with
fish occurrences. Understanding all these ecological aspects could help future management and conservation of NSPSF.
There are various secondary metabolites that have been identified in Polygonum minus Huds. or kesum plant, but
the production is often very low and depending on growth stage. Therefore, elicitation and in vitro techniques have
been suggested as an effective way for inducing secondary metabolites production in plant. This study was conducted
to determine the optimal conditions for P. minus root formation in vitro and to profile the metabolite content from
P. minus root culture with and without elicitor treatment. From the root induction study, it was found that the fresh
weight of induced root for nodal explant in MS liquid media supplemented with 0.5 mg/L NAA and shaken had the
highest production (0.38±0.08 g) compared to other treatments including the control. The results from metabolite
profile showed that the volatile compound of P. minus root produced without any elicitation contained 50.11% aliphatic
(27.59% aldehide, 9.17% alkane and 13.35% others) and 19.39% sesquiterpene (β-caryophyllene, α-bergamotene,
β-farnesene, α-caryophyllene dan β-curcumene) where the dodecanal compound (22.27%) and β-caryophyllene
(8.09%) have the highest percentage value for aliphatic and sesquiterpene group, respectively. Moreover, elicitation of
P. minus root culture using yeast extract at 100 mg/L concentration for 1 day demonstrated the ability to increase the
production of secondary metabolites in many volatile compounds of kesum in vitro root including the sesquiterpene
compounds compared to control treatment and other yeast extract elicitation treatments.
Microbial fuel cells (MFCs) have a high potential application for simultaneous wastewater treatment and electricity
generation. However, the choice of the electrode material and its design is critical and directly affect their performance.
As an electrode of MFCs, the anode material with surface modifications is an attractive strategy to improve the power
output. In this study, stainless steel (SS) and carbon steel (CS) was chosen as a metal anode, while graphite felt (GF)
was used as a common anode. Heat treatment was performed to convert SS, CS and GF into efficient anodes for MFCs.
The maximum current density and power density of the MFC-SS were achieved up till 762.14 mA/m2
and 827.25 mW/m2
respectively, which were higher than MFC-CS (641.95 mA/m2
and 260.14 mW/m2
) and MFC-GF (728.30 mA/m2
). Electrochemical impedance spectroscopy of MFC-SS showed better catalytic activity compared to MFC-CS and
MFC-GF anode, also supported by cyclic voltammetry test.
In vivo stability of biomaterial-based bone scaffolds often present a significant drawback in the development of materials
for tissue engineering purpose. Previously developed nanobiocomposite bone scaffold using alginate and nano cockle shell
powder has shown ideal characteristics. However, it showed high degradation rate and reduced stability in an in vivo
setting. In this study, we aim to observe the effect of cross-linking glutaraldehyde (GA) in three different concentrations
of 0.5%, 1% and 2% during the fabrication process as a potential factor in increasing scaffold stability. Microstructure
observations of scaffolds using scanning electron microscope (SEM) showed all scaffolds crossed linked with GA and
control had an ideal pore size ranging from 166.8-203.5 µm. Increase in porosity compared to the control scaffolds
was observed in scaffolds cross-linked with 2% GA which also presented better structural integrity as scored through
semi-quantitative methods. Tested pH values during the degradation period showed that scaffolds from all groups
remained within the range of 7.73-8.76. In vitro studies using osteoblast showed no significant changes in cell viability
but a significant increase in ALP enzyme levels in scaffold cross-linked with 2% GA. The calcium content released from
all scaffold showed significant differences within and between the groups. It can be concluded that the use of GA in the
preparation stage of the scaffold did not affect the growth and proliferation of osteoblast and use of 2% GA showed
improved scaffold structural integrity and porosity.
Instead of its economic impact, tin mining activities cause environmental problems. The tin occurrence which is related
to tin-bearing alteration on S-type Muncung Granite and its mining history in Singkep Island describes in this study. This
work assessed the heavy metals concentration in six tin tailings and two soils from Singkep using inductively coupled
plasma - mass spectrometry in correlation to environmental hazard. Both primary and placer mining methods applied
in tin excavations on the studied area. Concentration tendency of heavy metals in the six studied tailings samples is
generally Cr>Pb>As>Ba≈V. The identical heavy metals trend represented by the three samples from Bukit Tumang might
reflect a similar primary tailings character. On the other hand, anthropogenic activities and different surrounding rocks
caused the dissimilarity of heavy metals pattern on placer wastes. Higher environmental problems are detected on the
primary wastes than the placer one, especially arsenic and chrome. Severe arsenic pollution degree is also indicated in
the soil sample just outside the mining location at Betong Village. Conservation and amelioration programs are useful
in improving the environmental condition on studied locations.
Colorectal cancer refers to the cancer that occurs in the colon and rectum. It has been established as the third most
common cancer and the forth one in causing worldwide mortality. Cancer caused by the mutation of several genes that
usually involved in the regulation of cell proliferation, growth and cell death. The mutation that leads to abnormal
function of genes, either in enabling the genes to gain or loss of function was termed as driver mutation and the genes
with driver mutation ability was termed as driver genes. The identification of driver genes provides insight on mechanistic
process of cancer development where this information can be used to further understand their mode of action for causing
dysregulation in signaling pathways. In this study, two bioinformatic tools, i.e. CGI and iCAGES were used to predict
potential driver genes from the genome of eight colorectal cancer patients with annotated variants datasets. 44 unique
driver genes and 21 pathways have been identified; such as p53 signaling, PI3K-AKT, Endocrine resistance, MAPK and
cell cycle pathways. The identification of these pathways can lead to the identification of potential drugs targeting these