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The effects of led lighting on the commercial cultivation of Stevia rebaudiana / Narendren Rengasamy
No full textStevia rebaudiana is a perennial plant from the Asteraceae family, native to the highlands
of Brazil and Paraguay. It is a high-value crop due to the strong commercial demand for
its metabolites (steviol glycosides, SG) as an organic low-caloric sweetener with up to
300 times the sweetness of conventional sugar. Stevia rebaudiana a short-day plant, has
a tendency for a shortened vegetative stage and early flowering when grown under a
photoperiod of 12 h or less. The amount of SG in the leaves reduces by up to 50% after
flowering. Given the strong commercial demand for Stevia products, and the limited
supply available domestically, intense cultivation in controlled environment agriculture
(CEA) systems is a viable option. Lighting energy can account for more than 70% of the
total electrical energy used in a CEA system while the CEA system itself can consume
up to 100% more electrical energy compared to a conventional greenhouse. This study
included three experimental set-ups, using four different lighting strategies. All artificial
lighting systems used high powered light emitting diodes (LED). In the first experiment,
the plants were grown under Red + Blue light with photoperiods of 8, 12 or 16 hours (8H,
12H, 16H) and an intermittent photoperiod of 5 hours 20 minutes (16HI) per 8 hours (for
a total of 16 hours each day). A control sample was grown under natural sunlight and
photoperiod (12 hours) in the climate-controlled greenhouse (GH). In the second
experiment, the plants were grown under 6 different spectral compositions that had a base
Red + Blue (RB) spectra. The control plants were grown under pure RB spectra while
others were grown under RB supplemented with Far Red (FR), Ultraviolet A (UVA),
Blue (BR), Green (GR), FR+UVA+GR (FS). In the third experiment, varying fractions
of UV-A and green light in addition to the base RB was used. Two treatments with green
fractions (GR1 & GR2), two treatments with UVA (UV1 & UV2) and two treatments that
had both (UVGR1, UVGR2). A separate set of plants were grown under RB and natural
sunlight before being transferred to GR2, UV2, UVGR2, and monochromatic light treatments of blue, green and UVA, for 3 and 10 days before harvest. Plants grown under
the UVGR1 had the highest dry leaf biomass accumulation of 4.75 g plant-1 (P<.05).
UVA had the highest metabolite (ST + Reb A) concentration of 27% (P<.05) while plants
grown under sunlight had a mean SG concentration of 15%. UVGR1 had the highest
metabolite yields and energy use efficacy of 1.05 g plant-1 and 30.24 mg kWh-1 (P<.05)
respectively. In terms of productivity, the GR1 spectral composition was the most
productive, producing 18.7 (P<.05) milligrams of ST + Reb A compounds for every mol
of light used. Overall, this study demonstrated the effects of different lighting strategies
on the productivity and energy use efficacy of indoor grown Stevia rebaudiana. It was
observed that strategies that used spectral composition with green and UV-A were more
productive and had higher efficacies compared to photoperiod manipulation, or the use
of pre-harvest lighting
Entrepreneurial orientation and SME performance in Malaysia during the COVID-19 pandemic: The effects of economic stimulus packages and differentiation strategy / Natalia Inani Norsalehe
No full textIn March 2020, the World Health Organization (WHO) declared the COVID-19 outbreak as
a pandemic, leading countries to implement various measures to contain the spread, such as
social distancing, widespread lockdowns, and travel bans. These actions have had severe
economic consequences, with the downturn being considered more severe than previous
financial crises, including the Asian financial crisis, the global financial crisis, and the
subprime mortgage crisis. In Malaysia, 97.4% of businesses are small and medium-sized
enterprises (SMEs), and they contribute 37.4% and 47.8% of Malaysia’s GDP and
employment, respectively. During the COVID-19 pandemic, businesses have either halted or
closed down. Most companies have used up their savings to sustain their businesses, paying
for fixed costs, R&D, and others. To help ease their burden during the pandemic, the
Malaysian government has introduced various economic stimulus packages, such as
PRIHATIN, PENJANA, PERMAI, PEMERKASA, and PEMULIH, to support the “rakyat”
(people), including SMEs. However, the effectiveness and impact of the economic stimulus
packages on SME business performance are still arguable until to date. SMEs with high
entrepreneurial orientation (EO), tend to exhibit positive business performance. In
challenging times, SMEs need to be unique; they require financial assistance for R&D and
business expansion. It is crucial for SMEs to be different from their competitors to gain a
competitive advantage. Based on previous financial crises, SMEs still require time to recover
post-crisis despite the financial assistance provided to them in challenging markets. Hence,
this study aims to examine the effects of EO, SME performance, differentiation strategy, and
economic stimulus packages during the COVID-19 pandemic on SMEs in Malaysia. Based
on existing empirical research and the current environment during the COVID-19 pandemic,
five (5) hypotheses were developed for this study. This study underpins the Resource-Based View (RBV) theory and Contingency theory which fills the current gap in the EO and SME
performance relationship within the strategic management literature, particularly during the
COVID-19 pandemic in Malaysia. The research method for this study is based on
quantitative via questionnaires. The instruments for EO, SME performance, and
differentiation strategy were adopted and modified based on existing empirical instruments,
while the instruments for the economic stimulus packages were based on self-developed
constructs. The questionnaire consists of 61-items. A pilot test was conducted on 70
MD/CEO/business owners/business partners/senior representatives of SMEs, and a field
study was conducted on 325 for SMEs in Selangor, Kuala Lumpur, Johor Bahru, Perak, and
Pulau Pinang from the service and manufacturing industries. In analysing the result, first, the
hypotheses of interest were developed, then EFA is then conducted for ddetermining the
dimensionality of items and to evaluate internal factor loading. Subsequently, Pooled-CFA
was conducted for the validation of the constructs. Lastly SEM was conducted this is to
estimate the interaction among constructs. The data analysis was conducted using SPSS 26
and IBM SPSS AMOS 26. Based on the findings, all the five (5) hypotheses were supported
and significant. This study will contribute to SME development plans, post-COVID-19
pandemic and any future crises based on the economic stimulus packages and future
assistance provided by the Malaysian government
Impression management in social sustainability reporting before and during COVID-19: The case study of Top Glove Berhad / Ng Sin Yi
No full textThe study analyzes Top Glove Berhad (Top Glove)’s social sustainability reporting during the Coronavirus Disease 2019 (COVID-19) pandemic period. Specifically, its purpose is to investigate the extent of the impression management (IM) strategies used in employee and human rights information disclosure in its social sustainability reporting before and during the COVID-19. A qualitative content analysis of Top Glove’s social sustainability reports for the period of 2017 to 2021 was conducted. These length periods are selected because Top Glove has faced an allegation about human rights in the December of 2018. A content analysis was adopted as it is a flexible method that allows data to be presented in a variety of ways, such as quotations and words, diagrams, statistics, and percentages. The data analysis was separated into two phrase which include analysis of information disclosure in sentences and analysis of information disclosure in visual. In this case, an analysis of employee and human rights information in Top Glove’s sustainability reports was first performed in comparison to the Global Reporting Initiative (GRI) guidelines 2016 to evaluate the state of disclosure. The findings reveal that there are two interdependent and non-exclusive issues impacting the transparency and credibility of Top Glove statements. Furthermore, the evolution of disclosure practices has also been investigated in this study, demonstrating that Top Glove is committed to improving its employee and human rights information disclosure. Next, an investigation of IM tactics being adopted by Top Glove on its employee and human rights information disclosure have shown that there are five IM tactics used in its overall sustainability reporting. Moreover, the result also shows that Top Glove’s reports before the allegation revealed the corporation’s self-presentation iv
techniques and there are five IM tactics identified after the allegation. The findings suggest that the firm mostly attempted to show itself in the best light possible, highlighting its competency and competent problem-solving ability. Besides that, a visual analysis has been carried out in the next phrase to examine how employee and human rights issues are represented in Top Glove’s sustainability reports using a research instrument based on GRI standards. Thus, the study illustrates how photographs are utilized to generate images of diversity, safety, happiness, and mutual support. In the conclusion, companies should consider the users of sustainability reporting, such as corporate stakeholders, while choosing how to construct their sustainability reports and the IM methods to implement. Many individuals view sustainability reports as image-building public relations tools that provide a favorable image of a corporation. A frequent adoption of certain IM strategies may strengthen this impression, unknowingly informing the audience that the organization utilizes sustainability reports to establish a sustainable profile in the lack of true involvement and activities. This study would contribute to the existence of research on the numerous IM strategies utilized by organizations in times of crisis. Furthermore, this research broadens the scope of sustainable accounting research by focusing on employee and human rights information disclosures
Determinants of digital technology in accounting education through the lens of unified theory of acceptance and use of technology / Irene Wee Chui Man
No full textInnovating teaching methods in accounting education by leveraging technology is central to support the goal line of converting accounting education to cater for the needs of today’s accounting students. This study aims to find empirical evidence to explain accounting educators’ behavioural intention and use behaviour of digital technology based on the Unified Theory of Acceptance and Use of Technology (UTAUT) model. Using a quantitative approach, an online survey was administered to accounting educators working in either public or private universities in Malaysia. Partial least square (PLS), a variance-based latent variable structural equation modelling technique was used to analyse 156 valid survey and derive statistical results. The findings empirically attest the positive relation of performance expectancy, effort expectancy and social influence in enlightening the intention of accounting educators to use digital technology. Besides, behavioural intention also stands out as a critical influence on the actual use of digital technology. This study makes unique contributions to the research literature. It applies UTAUT in the accounting education context to help explicate the critical elements of the integration of digital technology for accounting educators. It also delivers insights into how UTAUT can be employed in the accounting education setting and offers ideas for boost usage of digital technology
Understanding the interactions between external and internal auditors in Indonesia: A theory of collaborative advantage / Fannia Rizal Putri
No full textThe study explored interactions between external and internal auditors in Indonesia during an audit engagement. This research aims to (1) examine how communications and communication and collaborations between External Auditors and Internal Auditors are operationalised in Indonesia, and (2) to understand how important interactions between external auditors and internal auditors are to the internal control systems in Indonesia. There is a lack of study exploring the interactions between external auditors and internal auditors which examines how they collaborate and communicate and the importance of external auditors and internal auditors’ interactions to the internal control systems, especially in developing countries such as Indonesia. To understand how collaboration between external auditors and internal auditors is operationalised during an audit engagement in Indonesia, a qualitative approach is chosen in this study. The Theory of the Collaborative Advantage lens is used as the framework of this study to assist the data collection phase. Semi-structured interviews were conducted with 16 participants: 8 external auditors and 8 internal auditors. The interview data is analysed using a thematic analysis approach. The Theory of Collaborative Advantage provides insights on the (1) Membership Structure, (2) Trust, (3) Common Aim, and (4) Power between external auditors and internal auditors in Indonesia. The findings indicated that collaborations between external auditors and internal auditors during an audit engagement in Indonesia operate smoothly due to a profound understanding and professionalism between the professions. The study also evidenced that good interaction between external auditors and internal auditors has gained sound internal control systems, specifically in detecting internal control deficiencies. The study contributes to the body of knowledge as the first study using the Theory of Collaborative Advantage in the auditing literature. The study demonstrated the significant importance of the operationalized communication and collaboration in practice between external auditors and internal auditors in Indonesia and its importance to the internal control system. Thus, understanding the operationalised between those professions may strengthen the corporate governance and reporting ecosystem
Synthesis and characterization of Prussian blue analogue and layered transition metal oxide cathodes for high performance sodium-ion batteries / Chen Yuncai
No full textEnergy storage must be applied to these renewable energies, such as solar, wind, and
tidal energy, due to their intermittent nature. The sodium-ion battery is one of the most
competitive candidates due to its low cost and abundant availability of sodium. In this
study, we focus on the cathode materials, namely Prussian blue analogues and P2-type
transition metal oxides. Na-rich PB-4M was synthesized by controlling the concentration
of Na+ ions during the synthesis process. PB-C with the cage-like porous structure was
synthesized via the re-heating method and acid etching. P2-type transition metal oxide
Na0.67(Li0.5Mg0.5)0.1(Ni0.33Mn0.67)0.9O2 (LMNM), with Li/Mg co-substitution, was
synthesized via a solid-state method. TGA, (in-situ) XRD, FTIR, and SEM, GITT, CV
were used to investigate the materials. PB-4M exhibited a specific capacity of 130 mAh/g
at RT and 120 mAh/g at 80 ℃. At 80 ℃, PB-4M could still deliver a reversible specific
capacity of 57 mAh/g at 2 C after 500 charge-discharge cycles. PB-C exhibited a specific
capacity of 112 mAh/g at 0.2 C and 97 mAh/g at 10 C and no obvious capacity fading,
with more than 80% capacity retention after the 1000th cycle. LMNM exhibited enhanced
cycling performance with a reversible capacity of 127 mAh/g and a capacity retention of
75% over 100 cycles at 0.5 C
Synthesis and characterization of molybdenum based nanocomposites film for water splitting applications / Choong Zheng Lin
No full textThe molybdenum-based nanocomposite films in the form of Mo2S3/MoP2 composite were prepared by using AACVD method with the single source precursor of [CpMo(CO)2(S2P(SPhMe)2)] (1) (Cp = C5H5) in THF at 0.01 M under argon gas flow in different deposition conditions inclusive of different deposition temperatures (450 °C, 550 °C, 650 °C), duration of deposition time (20 mins, 30 mins and 40 mins), different volume of precursor solution (10, 15, 20 and 25 mL) and carrier gas flow rate (0.3 and 0.5 SCFH). The bandgap energy values obtained in the visible light spectrum were close to the literature values for Mo2S3 and MoP2 at ~2.3 eV and ~2.8 eV, respectively. The deposition conditions had no significant effect on the band gap of the films. Among all the films synthesized for this study, the 20 ml/30 mins film fabricated at 550 °C with carrier gas flow rate of 0.3 SCFH generated the best current density of 10 mA/cm2 at 250 mV due to wide distribution of MoP2 grains across the film, which promoted significant interaction between Mo2S3 and MoP2 particles in the heterojunctions that provide sufficient amount of active sites for catalysing hydrogen evolution reaction (HER). With a favourable surface roughness, Rq of 106.4 nm resulted from suitable mean particle size of 1000-3000 nm coupled with film thickness of 968 nm had provided the film with abundance of active sites, which have the propensity to undergo HER reaction in 0.25 M H2SO4 acidic media (pH 0.95) owing to a low electron transport resistance of 0.715 kΩ. Based on the Tafel slopes, the approximate overall extracted values of 120 mV/dec for all the fabricated films indicated that Volmer reaction was the rate determining step in HER. Films fabricated at 450 °C with different volumes of precursor solution and deposition times were chosen as a study model for electrochemical studies in alkaline media prepared by mixing 0.25 M of Na2S and 0.35M of Na2SO3 (pH 11.71). It was found that oxygen evolution reaction (OER) was more significant than HER in alkaline media. However, the 20 mL/20 mins film fabricated at 450 °C with the carrier gas flow rate of 0.5 SCFH exhibited a large Tafel slope of 190 mV/dec and a very large onset potential of 1.14 V in OER. Therefore, Mo2S3/MoP2 composite material may not be a suitable electrocatalyst for OER activity in alkaline media. The electrochemical studies from fabrication of films under different synthesis conditions mentioned above via AACVD could be applied to determine an appropriate morphology that is suitable as electrocatalysts for water splitting application
Plasmonic enhanced dye−sensitized solar cells with phthaloyl chitosan−based gel polymer electrolyte / Shahan Shah
No full textIn this work, light absorption improves with the use of plasmonic nanoparticles by
photovoltaic (PV) devices. Silver (Ag, 100 nm size), gold (Au, 100 nm in size), copper
(Cu, 60−70 nm in size) and platinum (Pt) nanoparticles (NP) added to the titanium dioxide
(TiO2) active layer of dye sensitized solar cells (DSSCs) have improved performance.
The phthaloyl−chitosan based gel polymer electrolytes (GPEs) containing
tetrapropylammonium iodide (TPAI) salt, 1−butyl−3−methylimidazolium iodide (BMII)
ionic liquid (IL), tert−butyl pyridine (TBP), guanidine thiocyanate (GuSCN) as additives
and ( ) redox couple were used as an ion conducting medium for the DSSCs
operation. The highest ionic conductivity 12.69×10−3 S cm−1 was exhibited by the GPE
containing 3 wt.% GuSCN. The photocurrent density−photovoltage (J−V) characteristics,
intensity modulated photocurrent spectroscopy (IMPS) and intensity modulated voltage
spectroscopy (IMVS) were determined. On illuminating with AM1.5 (1000 W m−2) light,
DSSCs fabricated with 0 wt.% of NP constructed photoanode has exhibited
comparatively low solar cell efficiency (η) of 4.59% with short−circuit current density
of 9.90 mA cm−2 and open−circuit voltage of 0.69 V. The same cell also exhibited
charge transport time of 17.13 ms and charge recombination time of 36.43 ms. On
illuminating with AM1.5 light, the cell with 2 wt.% Ag NP in the photoanode exhibits an
η of 6.99 %. The is 14.25 mA cm−2, is 0.71 V and fill factor (FF) is 70%. The
DSSC with photoanode containing 2 wt.% Ag NP also exhibits of 7.00 ms and of
87.22 ms. On illumination with AM1.5 light, the cell with 3 wt.% Au NP in the
photoanode exhibits an η of 8.54% with of 19.82 mA cm−2, of 0.72 V and FF of 60%. The same cell also exhibited of 7.32 ms and of 115.33 ms. Under the
illumination of AM1.5, the DSSC with photoanode containing 3 wt.% of Cu NP exhibits
higher η of 7.19% with
of 13.35 mA cm−2, of 0.76 V and FF of 71%. The same
cell also exhibited the lowest of 2.30 ms and of 143.19 ms. Under the illumination
of AM1.5, the DSSC with photoanode containing with 3 wt.% of Pt NP exhibits higher η
of 6.54% with of 19.60 mA cm−2, of 0.51 V and FF of 65%
Predicting the onset of acute coronary syndrome events and in-hospital mortality using machine learning approaches / Song Cheen
No full textAcute coronary syndrome (ACS) represents a significant health concern, and its risk increases with exposure to environmental factors, particularly air pollution. Understanding this association is crucial given the increasing prevalence of air pollution in many regions, particularly in Malaysia, which is affected by air pollution. This study used a comprehensive methodology to investigate the relationship between air pollution and ACS patient outcomes utilizing machine learning (ML) algorithms, including: 1) Linear Regression, 2) Logistic Regression, 3) Support Vector Machine (SVM), 4) Random Forest (RF), 5) XGBoost, 6) Naïve Bayes (NB), and 7) Stacked Ensemble ML utilizing data from the National Cardiovascular Disease Database (NCVD) Malaysia registry and air quality data from the Department of Environment (DOE) Malaysia. The ML models for regression and classification were developed and optimized; the regression models aimed to predict ACS patients’ hospitalization and mortality rates, while the classification models were designed to predict the mortality risk of ACS patients under the influence of air pollution. The regression models reported an RMSE of 1.701 (RF) for predicting hospitalization rate and 0.440 (XGBoost) for predicting cardiac mortality rate on daily basis. The classification models demonstrated an AUC of 0.843 (95% CI: 0.813 – 0.873) (RF) with the in-hospital dataset and 0.840 (95% CI: 0.828 – 0.862) (XGBoost) using the emergency dataset, outperforming the conventional TIMI risk score, and the features importance is visualized using SHAP summary plots, whereby Nitrogen Oxides (NOx) and Ozone (O3) were identified as significant features impacting the ACS patient’s outcome for hospitalization, mortality rate and mortality risk. The best-performing ML models were then integrated into the 'My Heart ACS Air' web system (https://myheartacsair.uitm.edu.my/home.php), ensuring predictions are visualized and made accessible for healthcare professionals. This web system was developed using a prototype-driven approach, emphasizing user feedback, and evaluated using the System Usability Scale (SUS). The models not only provide accurate predictions but also outperform established risk scores in the presence of air pollution. The study's findings hold relevance for Malaysia, illustrating the importance of adopting such models in regions with significant air pollution. By visualizing these predictions via a web system, healthcare professionals can gain actionable insights, potentially leading to improved patient outcomes
Solation and characterization of compounds from the bark of Ochreinauclea maingayi (Hook. F.) RISDS. (Rubiaceae) with the aid of LCMS/MS molecular networking and their anticholinesterase activity / Norfaizah Osman
No full textA phytochemical investigation of the dichloromethane crude extract (DCE) from the bark of Ochreinauclea maingayi was performed with the aid of LCMS/MS-based molecular networking (MN) to accelerate the research workflow. MN permits extracting information on related molecules from the DCE based on the similarity of their fragmentation MS/MS spectra. In this study, one new indole alkaloid, dihydrodeglycocdambine (149), together with other twenty-one known compounds, was successfully identified from MN analysis. With the aid of LCMS/MS molecular networking, 149 was successfully isolated and purified from the bark of O. maingayi using the chromatography technique, together with sixteen knows compounds; neonaucline(5), naucledine (6), harmane (7), naulafine (33), cadambine (35), norharmane (124), methyl 9H-β-carboline-4-carboxylate (150), 1,2,3,4 tetranorharmane-1-one (151), cinnamamide (152), benzamide (153), scopoletine (154), 4′-hydroxyacetophenone (155), decarboxyportentol acetate (156), scoparone (157), 2’-hydroxy-3’-methoxyacetophenone (158) and hexyl p-coumarate (159). All structures were elucidated using spectroscopic methods; UV, IR, NMR and LCMS. The DCE of the bark of O. maingayi has been tested for butyrylcholinesterase (BChE) inhibitory assay inhibited moderately with more than 54 % with 100 μg/mL. Further evaluation showed that fractions 7 and 9 could inhibit the BChE at more than 80 % at 100 μg/mL. Both fractions yielded three compounds: harmane (7), naucledine (6) and dihydrodeglycocadambine (149). Naucledine (6) was the most potent BChE inhibitor with an IC50 value of 22.08 μM followed by harmane (7) and dihydrodeglycocadambine (149) (23.96 and 30.32 μM, respectively). According to the kinetic study, BChE was inhibited by 6 in a mixed mode type. A molecular docking (MD)
iv
analysis showed that 6 docked deep into the bottom gorge of BChE, interacted with Ser 198 and His 438 at the catalytic site, and formed hydrogen bonds with Gly 116 in an oxyanion hole