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PPKBSM, Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral (2025) EBB202- KRISTALOGRAFI DAN IKATAN DALAM PEPEJAL OCT 2024.
No full textPPKBSM, Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral (2025) EBB343 Characterization Of Engineering Materials SEM 1 SA 2024/2025
No full textPPKBSM, Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral (2025) EBS236 - Analytical Chemistry. [Teaching Resource] (Submitted)
No full textSex prediction using palatal surface of maxillary permanent lateral incisors
No full textSex determination is a crucial aspect of forensic anthropology and human
identification, aiding in narrowing down potential identities in forensic investigations.
This study aimed to assess the potential of using the palatal surface area (PSA) and
mesiodistal (MD) dimension of the maxillary lateral incisor for sex prediction within
the Malay population (Malaysian). A total of 100 dental casts (50 males and 50 females)
were analysed using 3D imaging software (3-Matic-Mimics, Materialise, Belgium), and
statistical analyses were conducted to determine the presence of sexual dimorphism and
the predictive accuracy of these dental features. The results indicated that the PSA of
the maxillary lateral incisor exhibited statistically significant sexual dimorphism, with
males having a larger mean PSA than females (p < 0.05). However, the MD dimension
did not show a significant difference between sexes (p > 0.05). Logistic regression
analysis identified PSA as a significant predictor for sex classification, but the overall
classification accuracy of the model was 61%, with 60.0% accuracy for males and 62.0%
for females. The area under the receiver operating characteristic (ROC) curve (0.39)
further indicated a poor discriminative ability of the model. These findings suggest that
the PSA of the maxillary lateral incisor only moderately predict sex, thus has limited
application in forensic management
Determination of chemical attribution substances in methamphetamine tablets by gas chromatography-mass spectrometry
No full textMethamphetamine abuse is a significant global concern. Chemical attribution substances (CAS) in methamphetamine tablets, including adulterants, diluents, and impurities, play a crucial role in forensic investigations by providing insights into manufacturing methods and trends in adulteration. However, routine forensic analyses typically focus on identifying and quantifying the primary drug component in seized methamphetamine tablets, with less emphasis on detecting CAS. Therefore, this study was aimed to identify and characterise CAS in seized illicit methamphetamine tablets using gas chromatography-mass spectrometry (GC-MS) to establish chemical profiles and assess trends in adulteration. In this study, a total of 161 methamphetamine tablets, seized by the Royal Malaysian Police in Kelantan state, were analysed using GC-MS. These samples were extracted with methanol followed by chromatographic separation and mass spectrometric identification. The presence of methamphetamine and caffeine were detected in all tested samples. The methamphetamine-to-caffeine ratio was found to be varied across samples, indicating inconsistencies in manufacturing processes and possible differences in source or synthesis methods. Most samples fell within the ratio range of 0.6 to 0.65 with 39 samples, representing 24.22% of the total samples. To conclude, this study could contribute to forensic drug intelligence by aiding in determining methamphetamine tablet sources and manufacturing trends. Establishing CAS profiles could enhance forensic investigations by linking illicit drug samples to specific production routes, supporting law enforcement efforts in combating drug trafficking
Forensic profiling of methamphetamine tablets by attenuated total reflectance-fourier transform infrared spectroscopy
No full textIllicit drug profiling is a vital aspect of forensic science, enabling law enforcement agencies to track drug distribution networks, identify adulteration trends, and enhance drug-related investigations. This study explores the application of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis (PCA) to chemically profile the methamphetamine tablets seized in Malaysia. In this study, a total of 161 methamphetamine tablet samples seized from the Kelantan region were analysed using ATR-FTIR spectroscopy. Subsequently, the ATR-FTIR profiles of these samples were subjected to PCA for clustering and discrimination. The results indicated that most samples contained high levels of adulterants, with caffeine being the most prevalent. The study also revealed that a significant proportion of the samples which is 157 samples (97.5%) contained less than 25% methamphetamine, suggesting the widespread adulteration practices aimed at increasing profit margins while maintaining stimulant effects. To conclude, the study demonstrates that ATR-FTIR spectroscopy, combined with PCA, offers a rapid, non-destructive, and cost-effective method for forensic profiling of drug samples. It allows forensic analysts to track drug sources, monitor manufacturing trends, and support law enforcement in combating illicit drug traffickin
Discrimination of various cosmetic products using ATR-FTIR spectroscopy and chemometrics
No full textIn today’s world, cosmetics have become an essential part in our everyday lives. Cosmetic products can serve as valuable evidence at crime scenes, as cosmetic smudges fall under the category of transfer evidence. The contact between a cosmetic user (whether victim or perpetrator) and objects or other individuals often results in the transfer of cosmetic residues, which can help link individuals to specific locations, events, or interactions. Furthermore, there has been limited forensic studies focus on analysis for discrimination of different types of cosmetic products. In this study, Attenuated Total Reflectance-Fourier Transform-Infrared (ATR-FTIR) spectroscopy, a rapid and non-destructive has been utilised to differentiate a total of 16 cosmetic products of four different types. Principal Component Analysis-Linear Discriminant Analysis (PCA-LDA) was employed to complement visual spectral comparisons and generate objective interpretation of the results. 100 % accuracy of predictive PCA-LDA model was established with all samples regardless of cosmetic types were correctly classified to their respective brands. The blind test was conducted with three unknown samples, which were correctly linked with their respective source. In persistence study, selected cosmetic products were exposed at room temperature and aged samples for up to 12 hours still showed similar spectral features similarly to their fresh samples that allowed identification. The current work demonstrated a quick, cost-effective, robust, and non-destructive method for differentiation of various cosmetic products in forensic investigatio
Misinformation effect in men and women crime scenario eye-witness recall
No full textEyewitness testimony is a crucial component of the criminal justice system, yet human memory is malleable and prone to distortion due to post-event misinformation. This phenomenon is known as the misinformation effect. This study explored the misinformation effect in eyewitness memory focusing on gender differences in memory responses among adult Malaysians. A total of 12 people participated in this study (male = 6, female = 6) and the participants were randomly divided into two groups, namely the control group and the experimental group. Utilizing a cross-sectional quasi-experimental design, male and female participants were shown a video depicting a crime and underwent an interview asking them to recall the incident. The participants in the experimental group were fed misleading information as opposed to the participants in the control group who were asked neutral questions. The findings revealed some patterns of memory responses which gave way to the themes: memory distortion, confidence in recall, resistance to misinformation, misinformation effect, subjective interpretation in recall and initial account of the incident. Gender differences in amongst these themes are also explored. Some implications of the study include highlighting the vulnerability of memory in the exposure to external information – which could be introduced intentionally for the purpose of misleading – especially in the criminal justice system. These reported memory distortions along with patterns from gender differences can be utilized in the development and application of a witness interview guideline that minimizes misleading information as well as a gender-based approach
Detection and effects of methamphetamine on the lifecycle of sarcophagidae in Malaysia
No full textForensic investigations often face challenges when determining the time and cause of death, especially in cases where remains are found in advanced decomposition. Forensic entomology, the study of insects that colonize decomposing remains, has become a crucial tool in forensic investigations, providing valuable insights into the post-mortem interval (PMI) and the cause of death. A more specialized field, forensic entomotoxicology, focuses on using insects to detect drugs and other chemical substances in decomposing tissues. Insects, particularly larvae, play a significant role in PMI estimation as they accumulate substances from decomposing bodies, offering a more sensitive method for detecting toxins with fewer interferences from decomposition by-products. The rising prevalence of methamphetamine (MA) abuse has led to numerous overdose deaths, where bodies are typically discovered after several days of decomposition. This delay complicates forensic investigations. To address this, forensic entomotoxicological analysis using insects is increasingly being used to detect the presence of drugs such as MA in decomposing tissues. In this study, pig liver mince was used to simulate the decomposition process and attract necrophagous insects, particularly Sarcophagidae. The liver was minced with two concentrations of MA (5 ng/mg and 10 ng/mg) to examine its impact on the lifecycle and morphology of Sarcophagidae. Samples were collected at various developmental stages for GC-FID analysis to detect MA presence. The results demonstrated that MA exposure delayed the lifecycle of Sarcophagidae, with insects exposed to 10 ng/mg MA taking 26 days to complete their lifecycle compared to 25 days for the 5 ng/mg MA-treated and control groups. Additionally, MA exposure resulted in a dose-dependent increase in the size and weight of larvae and pupae. However, adult flies from the MA-treated groups were slightly lighter compared to the control group. Notably, MA was detected in 3rd instar larvae at both concentrations and in adult flies at higher concentration, suggesting that the 3rd instar larvae are the most suitable stage for toxicological analysi
Prevalence and risk factors of sarcopenia among older adults with low socio-economic status (SES) in Kelantan
No full textThe functional status of older individuals is known to be negatively impacted by significant changes in body composition that come with ageing, such as a progressive loss of strength and decline in muscle quality and muscle mass. The present study investigated the prevalence and risk factors of sarcopenia among older adults with low socio-economic status (SES) in Kelantan. A total of 292 participants aged 60 years and above were recruited from five districts, namely as Tumpat, Pasir Mas, Bachok, Kota Bahru and Machang. The participants were grouped into three groups: non-sarcopenia, probable sarcopenia/sarcopenia, and severe sarcopenia using Asian Working Group Sarcopenia (AWGS) 2019 classification. The data collected were sociodemographic, anthropometry, body composition, physical fitness, dietary intake, cognitive function, food insecurity, anorexia of ageing and social support. All the participants were required to perform assessments such as anthropometry, body composition test, blood pressure and muscle strength test via hand grip strength and Short Physical Performance Battery (SPPB) test via balancing test, gait speed test, and chair stand test. Besides, all participants were required to answer a few questionnaires, namely the Lubben Social Network Scale (LSNS), Addenbrooke’s Cognitive Examination (ACE), Short Nutritional Assessment Questionnaire (SNAQ) and diet history questionnaire. Multivariate analysis was conducted using binary logistic regression with sarcopenia status as the dependent variable (no sarcopenia and a combination of probable, sarcopenia and severe sarcopenia). Findings showed that the prevalence of no sarcopenia, combination of probable sarcopenia/definitive sarcopenia as well as severe sarcopenia were 6.8%, 74.7%, and 18.4% respectively. In this study, non-sarcopenia subjects had the highest prevalence of overweight (50.0%) and the greatest waist circumference (87.5±14.3 cm) as compared to the other groups (p<0.001). Anorexia of ageing was significantly the highest among older adults with severe sarcopenia (55.6%) as compared to possible sarcopenia/sarcopenia (48.9%) and non-sarcopenia (20.0%). Prevalence of poor cognition was higher in the severe sarcopenia (87.3%), followed by the sarcopenia group (86.2%) and lowest in the normal group (73.4%). The result of this study has shown that the possible sarcopenia/sarcopenia group has the highest intake of sugar (23.7(23.8) g/d) but the lowest intake of vitamin C (54.1(55.6) mg/d) based on their dietary recall. Multivariate analysis showed that higher gait speed (95%CI: 1.681; 12.760; p=0.003) and longer sit-to-stand time (95%CI: 1.603; 6.159; p<0.001) significantly increased the risk of sarcopenia. Conversely, higher vitamin C intake reduced the risk (OR: 0.983; 95%CI: 0.970;0.997; p=0.018), while increased sugar intake raised the risk of sarcopenia (OR: 1.085; 95%CI: 1.008; 1.167; p=0.029). These findings suggest the importance of promoting physical fitness and a healthy diet, particularly increasing vitamin C-rich foods and reducing sugar consumption. Future interventions should focus on developing nutrition and exercise programs aimed at preventing sarcopenia among older adult