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Fulltext A secure and dependable trust assessment (SDTS) scheme for industrial communication networks

Khan T, Singh K, Ahmad K, Ahmad KAB

Sci Rep, 2023 Feb 02;13(1):1910.
PMID: 36732583 DOI: 10.1038/s41598-023-28721-x

Due to tamper-resistant sensor nodes and wireless media, Industrial Wireless Sensor Networks (WSNs) are susceptible to various security threats that severely affect industrial/business applications. The survival of sensor networks is highly dependent on the flourishing collaboration of sensor nodes. Trust management schemes seem to be realistic and promising techniques to improve security as well as cooperation (dependability) among sensor nodes by estimating the trust level (score) of individual sensor nodes. This research paper presents a well-organized and motivating secure, dependable trust assessment (SDTS) scheme for industrial WSNs to cope with unexpected behavior such as an on-off attack, bad-mouthing attack, garnished attack, etc., by employing robust trust evaluation components based on success ratio and node misbehaviour. SDTS incorporates an interesting trust evaluation function in which the trust range can be adjusted in accordance with the application requirement. SDTS include direct communication trust, indirect communication trust, data trust, and misbehavior-based trust to defend the multiple internal attacks. SDTS works according to the behavior of nodes, i.e., whether the sensor nodes are interacting frequently or not. Moreover, abnormal attenuation and dynamic slide lengths are incorporated in the proposed model (SDTS) to deal with various natural calamities and internal attacks. SDTS is compared against three recent state-of-the-art methods and found efficient in terms of ease of trust assessment, false-positive rate (2.5%), false-negative rate (2%), attack detection rate (90%), detection accuracy (91%), average energy consumption (0.40 J), and throughput (108 Kbps) under the load of 500 sensor nodes with 50% malicious nodes. Investigational results exhibit the potency of the proposed scheme.
Addressing education of speech-language pathologists in the World Report on Disability: development of a speech-language pathology program in Malaysia

Ahmad K, Ibrahim H, Othman BF, Vong E

Int J Speech Lang Pathol, 2013 Feb;15(1):37-41.
PMID: 23323816 DOI: 10.3109/17549507.2012.757709

The current paper is a response to the Wiley, McAllister, Davidson, and Marshall lead article regarding the application of the World Report on Disability (WRD) to people with communication disorders. The current paper directly addresses recommendation 5 (improvement of human resource capacity) and indirectly addresses recommendations 7, 8, and 9 (related to improving local knowledge and data on communicative disabilities) indirectly. The paper describes Malaysia's initiatives in the early 1990s, in developing its local professional capacity to provide services for people with communication disorders (PWCD). It charts the history of development of a local undergraduate entry-level degree program for speech-language pathology (SLP) from the point of conceptualization to full execution. The article provides glimpses to the processes and challenges faced by Universiti Kebangsaan Malaysia as the pioneer university in the South East Asia region to undertake the training and education of the SLP profession and highlights relevant issues faced by newly introduced professions in a country where resources and practice traditions were previously unavailable. It underscores the important role played by government institutions and an international professional network in driving forward-looking policies to implement and sustain the program.
An exploratory study on speech and hearing outcomes in children with cleft lip and palate

Mohd Ibrahim H, Mohamed Yusoff FH, Ahmad K, Van Dort S

Med J Malaysia, 2015 Dec;70(6):321-5.
PMID: 26988203 MyJurnal

INTRODUCTION: Little is known about the treatment outcomes of children with cleft lip and/or palate (CLP) receiving surgical care for primary lip and palate closure in Malaysia.
OBJECTIVES: This study examined the speech and hearing status of Malay-speaking children with CLP residing in Kuala Lumpur.
METHODS: Parents whose children were between the age of 5 and 7 years were recruited via the Cleft Lip and Palate Association of Malaysia (CLAPAM) registry. Parents completed a survey and the children completed a speech and hearing assessment at the Audiology and Speech Sciences Clinic, Universiti Kebangsaan Malaysia.
OUTCOMES: Speech measures include nasality rating, nasalance scores, articulation errors and speech intelligibility rating, while hearing measures include hearing thresholds and tympanometry results for each child.
RESULTS: Out of 118 registered members who fulfilled the inclusion criteria, 21 agreed to participate in the study. The overall speech and hearing status of children in this sample were poor. Only four (19%) participants had normal speech intelligibility rating and normal hearing bilaterally. In terms of overall cleft management, only four (19%) participants were seen by a cleft team while seven (33%) had never had their hearing tested prior to this study.
CONCLUSION: Participants in this sample had poor outcomes in speech and hearing and received uncoordinated and fragmented cleft care. This finding calls for further large scale research and collaborative efforts into improving and providing centralised, multidisciplinary care for children born with CLP.
Analysis Method for Laryngeal High-Speed Videoendoscopy: Development of the Criteria for the Measurement Input

Mohd Khairuddin KA, Ahmad K, Mohd Ibrahim H, Yan Y

J Voice, 2021 Jul;35(4):636-645.
PMID: 31864891 DOI: 10.1016/j.jvoice.2019.12.005

Despite its clear advantages, laryngeal high-speed videoendoscopy (LHSV) has not yet been accepted as a routine imaging tool for the evaluation of vocal fold vibration due to the unavailability of methods to effectively analyze the huge number of images from the LHSV recording. Recently, a promising LHSV-based analysis method has been introduced. The ability of this analysis method in studying the vocal fold vibratory behaviors had been substantially demonstrated. However, some practical aspects of its clinical applications still require further attention. Most fundamental is that the criteria for the measurement input ie, a segment of interest (SOI), which has not been fully defined. Particularly, the length of the SOI and the location along the sample, where it needs to be selected require further confirmation. Meanwhile, the analysis using any options of a well-delineated glottal area demands verification. Without clear criteria for the SOI, it is difficult to demonstrate the relevance of this analysis method in clinical voice assessment. Therefore, the aim of the present study is to establish the criteria for the SOI, which involved the investigations on the length of the SOI and the location along the sample, where it needs to be selected, as well as the use of any options of a well-delineated glottal area for analysis. The participants in the present study consisted of 36 young normophonic females. The methods involved LHSV recording of the images of the vibrating vocal folds. The captured images were then analyzed using the method. The LHSV-based measures from the analyses were compared according to the specified procedures of each investigation. Results indicated that 2000 frames should be used as the SOI length. The SOI could be selected at any location along the sample as long as well-delineated glottal areas were observed. With the current findings, a more conclusive measurement protocol is available to ensure reliable LHSV-based measures. The findings further support this analysis method for clinical application, which in turn promote LHSV as a reliable laryngeal imaging tool in clinical setting.
Fulltext Anti-tumour promoting activity and antioxidant properties of girinimbine isolated from the stem bark of Murraya koenigii S

Kok YY, Mooi LY, Ahmad K, Sukari MA, Mat N, Rahmani M, et al.

Molecules, 2012 Apr 20;17(4):4651-60.
PMID: 22522395 DOI: 10.3390/molecules17044651

Girinimbine, a carbazole alkaloid isolated from the stem bark of Murraya koenigii was tested for the in vitro anti-tumour promoting and antioxidant activities. Anti-tumour promoting activity was determined by assaying the capability of this compound to inhibit the expression of early antigen of Epstein-Barr virus (EA-EBV) in Raji cells that was induced by the tumour promoter, phorbol 12-myristate 13-acetate. The concentration of this compound that gave an inhibition rate at fifty percent was 6.0 µg/mL and was not cytotoxic to the cells. Immunoblotting analysis of the expression of EA-EBV showed that girinimbine was able to suppress restricted early antigen (EA-R). However, diffused early antigen (EA-D) was partially suppressed when used at 32.0 µg/mL. Girinimbine exhibited a very strong antioxidant activity as compared to a-tocopherol and was able to inhibit superoxide generation in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced differentiated premyelocytic HL-60 cells more than 95%, when treated with the compound at 5.3 and 26.3 µg/mL, respectively. However girinimbine failed to scavenge the stable diphenyl picryl hydrazyl (DPPH)-free radical.
Fulltext Antifungal efficacy of Moringa oleifera leaf and seed extracts against Botrytis cinerea causing gray mold disease of tomato (Solanum lycopersicum L.)

Ahmadu T, Ahmad K, Ismail SI, Rashed O, Asib N, Omar D

Braz J Biol, 2020 11 12;81(4):1007-1022.
PMID: 33175006 DOI: 10.1590/1519-6984.233173

Drawbacks associated with the use of chemical fungicides to control plant pathogenic fungi such as Botrytis cinerea stimulate the need for alternatives. Therefore, the present study was carried out to determine the antifungal potentials of Moringa oleifera extracts against B. cinerea. Phytochemical analysis using qualitative chemical tests revealed the presence of huge amount of crucial phytochemicals compounds like phenolic compounds, alkaloids and saponins in the M. oleifera leaf extract. Antifungal bioassay of the crude extracts indicated better mycelial growth inhibition by methanol leaf extract (99%). The minimum inhibitory concentration (MIC) was 5 mg/ml with 100% spore germination inhibition and minimum fungicidal concentration (MFC) was 10 mg/ml with 98.10% mycelial growth inhibition using broth micro dilution and poisoned food techniques. Gas chromatography-mass spectrometry (GC-MS) analysis led to the identification of 67 volatile chemical compounds in the leaf extract with 6-decenoic acid (Z)- (19.87%) was the predominant compound. Further chemical elucidation of the crude extracts performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed the presence of non-volatile chemical compounds, mostly flavones, flavonoids and phenolic acids (i.e. quercetin and kaempferol). Scanning electron microscopy and transmission electron microscopy analysis showed positive effect of M. oleifera leaf extract on the treated conidia and mycelium of B. cinerea. Findings revealed that irreversible surface and ultra-structural changes with severe detrimental effects on conidia and mycelium morphology compared to control treatment. Overall findings suggested that M. oleifera leaf extract is a promising candidate for biological control of fungal pathogens, thus limiting overdependence on chemical fungicides.
Arabic phoneme-grapheme correspondence by non-native, deaf children with cochlear implants and normal hearing children

Anis FN, Umat C, Ahmad K, Abdul Hamid B

Cochlear Implants Int, 2022 Nov;23(6):347-357.
PMID: 36005236 DOI: 10.1080/14670100.2022.2114583

OBJECTIVE: This study aimed to compare the error patterns of Arabic phoneme-grapheme correspondence by a group of Malay children with cochlear implants (CIs) and normal hearing (NH) and the effects of the visual graphical features of Arabic graphemes (no-dot, single-dot, and multiple-dots) on the phoneme-grapheme correspondence.
METHODS: Participants were matched for hearing age (Mean, M = 7 ± 1.03 years) and duration of exposure to Arabic sounds (M = 2.7 ± 1.2 years). All 28 Arabic phonemes were presented through a loudspeaker and participants pointed to the graphemes associated with the presented phonemes.
RESULTS: A total of 336 and 616 tokens were collected for six children with CI and 11 NH children for each task, i.e., phonemes repetition and phoneme-grapheme correspondence. Both groups found it easier to repeat phonemes than the phoneme-grapheme correspondence. The children with CIs showed more confusion ([ظ, ز, ذ, ض, خ, ب, ه, س, ع, & ث] >10% correct scores) in phoneme-grapheme correspondence than the NH children ([ظ:14%] and [ث: 27%]). There was a significant interaction (p = 0.001) among the three visual graphical features and hearing status (CI and NH).
CONCLUSION: Our results infer that non-native Malay children with CIs and NH use different strategies to process the Arabic graphemes' visual features for phoneme-grapheme correspondence.
Fulltext Association between Serum 25 (OH) Vitamin D Concentrations and Inflammatory Bowel Diseases (IBDs) Activity

Hassan V, Hassan S, Seyed-Javad P, Ahmad K, Asieh H, Maryam S, et al.

Med J Malaysia, 2013;68(1):34-8.
PMID: 23466764

Inflammatory bowel diseases (IBDs) are immune mediated diseases affecting the gastrointestinal tract. Several environmental factors in concert with genetic susceptibilities can trigger IBDs. Recently, one of the important environmental factors contributing to the development of autoimmune diseases is vitamin D (VitD) deficiency. Furthermore, some new evidence points to VitD deficiency and its receptor dysfunction as an underlying factor for the emergence experimental IBDs. The aim of the current study was to evaluate the correlation between serum 25(OH)D concentrations and IBD activity in patients with ulcerative colitis or Crohn's disease. Sixty patients with confirmed diagnosis of IBD were recruited for a cross sectional study. Most of the identified confounders affecting serum VitD concentrations were excluded. Disease activity was assessed using validated questionnaires, including Truelove for Ulcerative Colitis and Crohn Disease Activity Index (CDAI) for Crohn disease. Serum 25(OH)D concentrations were determined by chemiluminescent assay. Serum 25(OH)D≤10 (ng/ml) was considered as VitD deficiency and 11≤25(OH)D<29(ng/ml) as VitD insufficiency. Mean serum 25(OH)D value was 13.1 ± 11.1(ng/ml) in IBD patients. Almost 95% of patients were vitamin D insufficient or deficient. Forty one percent of IBD patients had active disease. VitD deficiency was not associated with IBD activity (p=0.23). However, VitD deficiency was significantly associated with a history of IBD related intestinal surgery (p=0.001). In conclusion, this cross-sectional prospective study suggested that there is no association between vitamin D deficiency and disease activity in a relatively small number of IBD patients in a short period of time.
Bromelain: an overview of industrial application and purification strategies

Arshad ZI, Amid A, Yusof F, Jaswir I, Ahmad K, Loke SP

Appl Microbiol Biotechnol, 2014 Sep;98(17):7283-97.
PMID: 24965557 DOI: 10.1007/s00253-014-5889-y

This review highlights the use of bromelain in various applications with up-to-date literature on the purification of bromelain from pineapple fruit and waste such as peel, core, crown, and leaves. Bromelain, a cysteine protease, has been exploited commercially in many applications in the food, beverage, tenderization, cosmetic, pharmaceutical, and textile industries. Researchers worldwide have been directing their interest to purification strategies by applying conventional and modern approaches, such as manipulating the pH, affinity, hydrophobicity, and temperature conditions in accord with the unique properties of bromelain. The amount of downstream processing will depend on its intended application in industries. The breakthrough of recombinant DNA technology has facilitated the large-scale production and purification of recombinant bromelain for novel applications in the future.
Fulltext CFD study on NACA 4415 airfoil implementing spherical and sinusoidal Tubercle Leading Edge

Aftab SMA, Ahmad KA

PLoS One, 2017;12(8):e0183456.
PMID: 28850622 DOI: 10.1371/journal.pone.0183456

The Humpback whale tubercles have been studied for more than a decade. Tubercle Leading Edge (TLE) effectively reduces the separation bubble size and helps in delaying stall. They are very effective in case of low Reynolds number flows. The current Computational Fluid Dynamics (CFD) study is on NACA 4415 airfoil, at a Reynolds number 120,000. Two TLE shapes are tested on NACA 4415 airfoil. The tubercle designs implemented on the airfoil are sinusoidal and spherical. A parametric study is also carried out considering three amplitudes (0.025c, 0.05c and 0.075c), the wavelength (0.25c) is fixed. Structured mesh is utilized to generate grid and Transition SST turbulence model is used to capture the flow physics. Results clearly show spherical tubercles outperform sinusoidal tubercles. Furthermore experimental study considering spherical TLE is carried out at Reynolds number 200,000. The experimental results show that spherical TLE improve performance compared to clean airfoil.
CT coronary angiogram in children with Kawasaki patients: experience in 52 patients

Borhanuddin BK, Abdul Latiff H, Mohamed Yusof AK

Cardiol Young, 2022 Dec;32(12):1994-1998.
PMID: 35707919 DOI: 10.1017/S1047951122000154

BACKGROUND: CT is an accepted non-invasive imaging tool to assess the coronary arteries in adults; however, its utilisation in children is limited by high heart rate and lack of standardised protocol. We sought to assess diagnostic quality and factors that affect image quality of CT in assessing coronary artery lesions in Kawasaki patients less than 18 years of age.
METHODOLOGY: CT coronary angiography was performed on patients with Kawasaki disease diagnosed with coronary aneurysm or suspected to have coronary stenosis. Studies were performed using electrocardiogram-gated protocols. General anaesthesia was used in patients who were not cooperative for breathing control. Heart rate, image quality, and effective radiation dose were documented.
RESULTS: Fifty-two Kawasaki patients underwent CT coronary angiography to assess coronary artery lesions. Median heart rate was 88 beats per minute (range 50-165 beats/minute). Image quality was graded as excellent in 34 (65%) patients, good in 17 (32%), satisfactory in 1, and poor in 1 patient. Coronary artery aneurysm was found in 25 (bilateral = 6, unilateral = 19, multiple = 11). Thrombus was found in 11 patients resulting in partial and total occlusion in 8 and 3 patients, respectively. Coronary stenosis was noted in 2 patients. The effective radiation dose was 1.296 millisievert (median 0.81 millisievert). Better diagnostic imaging quality was significantly related to lower heart rate (p = 0.007).
CONCLUSION: Electrocardiogram-triggered CT coronary angiography provides a good diagnostic assessment of coronary artery lesions in children with Kawasaki disease.
Fulltext Chitosan Nanoparticles as Carriers for the Delivery of ΦKAZ14 Bacteriophage for Oral Biological Control of Colibacillosis in Chickens

Adamu Ahmad K, Sabo Mohammed A, Abas F

Molecules, 2016 Mar 14;21(3):256.
PMID: 26985885 DOI: 10.3390/molecules21030256

The use of chitosan as a delivery carrier has attracted much attention in recent years. In this study, chitosan nanoparticles (CS-NP) and chitosan-ΦKAZ14 bacteriophage-loaded nanoparticles (C-ΦKAZ14 NP) were prepared by a simple coercavation method and characterized. The objective was to achieve an effective protection of bacteriophage from gastric acids and enzymes in the chicken gastrointestinal tract. The average particle sizes for CS-NP and C-ΦKAZ14 NP were 188 ± 7.4 and 176 ± 3.2 nm, respectively. The zeta potentials for CS-NP and C-ΦKAZ14 NP were 50 and 60 mV, respectively. Differential scanning calorimetry (DSC) of C-ΦKAZ14 NP gave an onset temperature of -17.17 °C with a peak at 17.32 °C and final end set of 17.41 °C, while blank chitosan NP had an onset of -20.00 °C with a peak at -19.78 °C and final end set at -20.47. FT-IR spectroscopy data of both CS-NP and C-ΦKAZ14 NP were the same. Chitosan nanoparticles showed considerable protection of ΦKAZ14 bacteriophage against degradation by enzymes as evidenced in gel electrophoresis, whereby ΦKAZ14 bacteriophage encapsulated in chitosan nanoparticles were protected whereas the naked ΦKAZ14 bacteriophage were degraded. C-ΦKAZ14 NP was non-toxic as shown by a chorioallantoic membrane (CAM) toxicity assay. It was concluded that chitosan nanoparticles could be a potent carrier of ΦKAZ14 bacteriophage for oral therapy against colibacillosis in poultry.
Fulltext Closing the global cancer divide--performance of breast cancer care services in a middle income developing country

Lim GC, Aina EN, Cheah SK, Ismail F, Ho GF, Tho LM, et al.

BMC Cancer, 2014;14:212.
PMID: 24650245 DOI: 10.1186/1471-2407-14-212

BACKGROUND: Cancer is the leading cause of deaths in the world. A widening disparity in cancer burden has emerged between high income and low-middle income countries. Closing this cancer divide is an ethical imperative but there is a dearth of data on cancer services from developing countries.
METHODS: This was a multi-center, retrospective observational cohort study which enrolled women with breast cancer (BC) attending 8 participating cancer centers in Malaysia in 2011. All patients were followed up for 12 months from diagnosis to determine their access to therapies. We assess care performance using measures developed by Quality Oncology Practice Initiative, American Society of Clinical Oncology/National Comprehensive Cancer Network, American College of Surgeons' National Accreditation Program for Breast Centers as well as our local guideline.
RESULTS: Seven hundred and fifty seven patients were included in the study; they represent about 20% of incident BC in Malaysia. Performance results were mixed. Late presentation was 40%. Access to diagnostic and breast surgery services were timely; the interval from presentation to tissue diagnosis was short (median = 9 days), and all who needed surgery could receive it with only a short wait (median = 11 days). Performance of radiation, chemo and hormonal therapy services showed that about 75 to 80% of patients could access these treatments timely, and those who could not were because they sought alternative treatment or they refused treatment. Access to Trastuzumab was limited to only 19% of eligible patients.
CONCLUSIONS: These performance results are probably acceptable for a middle income country though far below the 95% or higher adherence rates routinely reported by centres in developed countries. High cost trastuzumab was inaccessible to this population without public funding support.
Fulltext Comet 17P/Holmes

Othman, M., Ahmad, K.

ASM Science Journal, 2007;1(2):181-182.
MyJurnal

Comet 17P/Holmes was discovered by Edwin Holmes on 6 November 1892 while he was conducting regular observations of the Andromeda Galaxy (M31). Calculations using observation of its orbits established the perihelion date as 13 June and the orbital period as 6.9 years. The 1899 and 1906 appearances were observed, but the comet was only seen again in 1964. The comet has since been
observed on every subsequent return.
Fulltext Comet Lulin

Othman, M., Ahmad, K.

ASM Science Journal, 2008;2(2):183-183.
MyJurnal

Comet Lulin was discovered by Lin Chi-Sheng and Ye Quanzhi using the 16-inch telescope at Lulin Observatory in Nantou, Taiwan in 2007. According to Brian Marsden of the Smithsonian Astrophysical Observatory, it reached its perihelion on 10 January 2009 at a distance of 113 million
km from the Sun. It moves in a very nearly parabolic retrograde (‘backwards’ compared to the movement of the planets) orbit at an inclination of 1.6 degrees from the ecliptic (“Newfound Comet Lulin to Grace Night Skies”). http://www.space.com/spacewatch/090206-ns-cometlulin.html). It passed nearest to the Earth at a distance of 61 million km on 23 February 2009.
Computational Analysis of Protein-Protein Interactions in Motile T-Cells

Kumar S, Fazil MHUT, Ahmad K, Tripathy M, Rajapakse JC, Verma NK

Methods Mol Biol, 2019;1930:149-156.
PMID: 30610609 DOI: 10.1007/978-1-4939-9036-8_18

Analysis of protein-protein interactions is important for better understanding of molecular mechanisms involved in immune regulation and has potential for elaborating avenues for drug discovery targeting T-cell motility. Currently, only a small fraction of protein-protein interactions have been characterized in T-lymphocytes although there are several detection methods available. In this regard, computational approaches garner importance, with the continued explosion of genomic and proteomic data, for handling protein modeling and protein-protein interactions in large scale. Here, we describe a computational method to identify protein-protein interactions based on in silico protein design.
Fulltext Current strategies and perspectives in detection and control of basal stem rot of oil palm

Siddiqui Y, Surendran A, Paterson RRM, Ali A, Ahmad K

Saudi J Biol Sci, 2021 May;28(5):2840-2849.
PMID: 34012325 DOI: 10.1016/j.sjbs.2021.02.016

The rapid expansion of oil palm (OP) has led to its emergence as a commodity of strategic global importance. Palm oil is used extensively in food and as a precursor for biodiesel. The oil generates export earnings and bolsters the economy of many countries, particularly Indonesia and Malaysia. However, oil palms are prone to basal stem rot (BSR) caused by Ganoderma boninense which is the most threatening disease of OP. The current control measures for BSR management including cultural practices, mechanical and chemical treatment have not proved satisfactory. Alternative control measures to overcome the G. boninense problem are focused on the use of biological control agents and many potential bioagents were identified with little proven practical application. Planting OP varieties resistant to G. boninense could provide the ideal long-term solution to basal stem rot. The total resistance of palms to G. boninense has not yet been reported, and few examples of partial resistances have been observed. Importantly, basidiospores are now recognized as the method by which the disease is spread, and control methods require to be revaluated because of this phenomenon. Many methods developed to prevent the spread of the disease effectively are only tested at nursery levels and are only reported in national journals inhibiting the development of useful techniques globally. The initial procedures employed by the fungus to infect the OP require consideration in terms of the physiology of the growth of the fungus and its possible control. This review assesses critically the progress that has been made in BSR development and management in OP.
Fulltext Deciphering the Physicochemical and Microscopical Changes in Ganoderma boninense-Infected Oil Palm Woodblocks under the Influence of Phenolic Compounds

Surendran A, Siddiqui Y, Ahmad K, Fernanda R

Plants (Basel), 2021 Aug 28;10(9).
PMID: 34579330 DOI: 10.3390/plants10091797

The threat of Ganoderma boninense, the causal agent of basal stem rot disease, in the oil palm industry warrants finding an effective control for it. The weakest link in the disease management strategy is the unattended stumps/debris in the plantations. Hence, this study aimed to determine whether the selected phenolic compounds could control G. boninense in inoculated oil palm woodblocks and restrict wood biodegradation. Results indicated a significant reduction in the wood mass loss when treated with all the phenolic compounds. Surprisingly, syringic and vanillic acids behaved ambivalently; at a lower concentration, the wood mass loss was increased, but it decreased as the concentrations were increased. In all four phenolic compounds, the inhibition of mass loss was dependent on the concentration of the compounds. After 120 days, the mass loss was only 31%, with 63% relative degradation of lignin and cellulose, and 74% of hemicellulose and wood anatomy, including silica bodies, were intact in those woodblocks treated with 1 mM benzoic acid. This study emphasizes the physicochemical and anatomical changes occurring in the oil palm wood during G. boninense colonization, and suggests that treating oil palm stumps with benzoic acid could be a solution to reducing the G. boninense inoculum pressure during replantation in a sustainable manner.
Description of the Features and Vibratory Behaviors of the Nyquist Plot Analyzed From Laryngeal High-Speed Videoendoscopy Images

Mohd Khairuddin KA, Ahmad K, Mohd Ibrahim H, Yan Y

J Voice, 2020 Aug 26.
PMID: 32861565 DOI: 10.1016/j.jvoice.2020.07.036

Facilitative playback-based subjective measures offer a more reliable evaluation of the vocal fold vibration than those derived from direct inspection of video playback. One of the measures is a Nyquist plot, which presents the analyzed cycle-to-cycle vibratory information in a graphical form. While the potential is evident, the information of the features of the Nyquist plot, which the evaluation is based on, is still incomplete. The current identified features and their vibratory behaviors may be inadequate to guarantee accurate interpretation of the findings. The present study aims to address this issue by examining the features of the Nyquist plot and their vibratory behaviors. A total of 56 young normophonic speakers, that is, 20 males and 36 females were recruited as the participants. Each of them underwent laryngeal high-speed videoendoscopy to record the images of the vocal fold vibration, which were then analyzed to generate the Nyquist plots. The features were identified by inspecting the properties of the plot points forming the Nyquist plots. For each identified feature, its vibratory behaviors were examined. The results revealed four features: rim contour depicting the longitudinal phase difference; left edge shape signifying the glottal configuration, phase closure, and closed phase duration; rim width and rim pattern visualizing the regularity of glottal areas and the regularity of the intracycle variations, respectively. The findings present a more complete reference of the features and their vibratory behaviors that is pertinent for the Nyquist plot interpretation.
Fulltext Design, synthesis and cytotoxic evaluation of o-carboxamido stilbene analogues

Azmi MN, Din MF, Kee CH, Suhaimi M, Ping AK, Ahmad K, et al.

Int J Mol Sci, 2013;14(12):23369-89.
PMID: 24287912 DOI: 10.3390/ijms141223369

Resveratrol, a natural stilbene found in grapes and wines exhibits a wide range of pharmacological properties. Resveratrol is also known as a good chemopreventive agent for inhibiting carcinogenesis processes that target kinases, cyclooxygenases, ribonucleotide reductase and DNA polymerases. A total of 19 analogues with an amide moiety were synthesized and the cytotoxic effects of the analogues on a series of human cancer cell lines are reported. Three compounds 6d, 6i and 6n showed potent cytotoxicity against prostate cancer DU-145 (IC50=16.68 µM), colon cancer HT-29 (IC50=7.51 µM) and breast cancer MCF-7 (IC50=21.24 µM), respectively, which are comparable with vinblastine. The resveratrol analogues were synthesized using the Heck method.

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