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PPKBSM, Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral (2025) EBS201-3 - MINERAL DEPOSITS - FEBRUARY 2025. [Teaching Resource]
No full textPPKBSM, Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral (2025) EBB323 SEMICONDUCTOR FABRICATION TECHNOLOGY SEM 1 SA 2024/2025.
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Screening of the anti-proliferative effects of baicalein and carbon nanodot combination on hela cancer cells
No full textThis study identifies the anti-proliferative effects of a novel combination therapy using baicalein, a flavonoid, and carbon nanodots (CDs) on HeLa cervical cancer cells. Baicalein, known for its potent anti-cancer properties, has shown limitations in clinical applications due to low bioavailability. Carbon nanodots, with their excellent biocompatibility, solubility, and drug delivery potential, were used as a carrier to enhance the therapeutic efficacy of baicalein. The study evaluated the anti-proliferative effects of the baicalein-carbon nanodot (Bai-CDs) combination in comparison to standalone treatments of baicalein, CDs, and cisplatin on HeLa cells using the MTT assay. Results demonstrated that the combination therapy significantly inhibited cell proliferation in a dose-dependent manner with the IC50 69.85 ± 4.145μg/ml and p-value less than 0.05. These findings highlight the potential of the Bai-CDs combination as a new therapeutic strategy for cervical cancer, providing enhanced bioavailability and targeted anti-cancer effects while minimizing adverse outcomes associated with conventional chemotherap
Effect of 12 hours overnight fasting on brain perfusion using TC-99M ETHYL cysteinate dimer Spect/Ct with scenium analysis in smokers
No full textCigarette smoking is not only a common habit that occurs in Malaysia but also the whole world. This habit has been common among adults but nowadays teenagers are also addicted to smoking cigarettes. The destructive substances in cigarettes such as nicotine can reduce activity in limbic, posterior cingulate, prefrontal cortex and increase activity in their cuneus and precuneus. This study recruited subjects that are 18 years old and above and fulfill inclusion and exclusion criteria, smokers (n=18) from Klinik Rawatan Keluarga (KRK) and non-smokers (n=11) from volunteer poster. The brain perfusion between both groups was compared by using Single Photon Emission Computed Tomography-Computed Tomography (SPECT/CT) in Hospital Universiti Sains Malaysia (HUSM) by using technetium-99m-ethyl cysteinate dimer (99mTc-ECD) as a radiotracer for both fasting and non-fasting state and Scenium software was use for quantitative brain image interpretation. Smokers were categorized into mild (n=17), moderate (n=1) and severe smoker (n=0) based on level of addiction fagerstrom questionnaire. Thus, this study objectives were to determine brain perfusion between smoker and non-smoker, to compare the difference in brain perfusion among smoker between fasting and non-fasting state and to compare the difference in brain perfusion among non-smoker between fasting and non-fasting state. The result of Mann Whitney U test for the first objective shows that there is significant difference in left and right of superior frontal gyrus (SFG) dorsolateral and orbital. Wilcoxon Signed Rank test was used for second and third objective and there is significant difference in left amygdala among smoker and no significant difference in brain perfusion area observed among non-smokers after overnight fasting (12 hours fasting)
Evaluation of source loading position in HDR brachytherapy dose calculation for patients with oral tongue cancer
No full textThe dosimetric impact of six different dwell activation strategies in high-dose-rate (HDR) interstitial brachytherapy for oral tongue squamous cell carcinoma (OTSCC) was retrospectively investigated in twenty patients. Treatment plans were generated using Oncentra Treatment Planning System (TPS) with varying source loading configurations: Initial activation (uniform 0.25 cm spacing), system-optimized Autoactivation, fixed spacings of 0.50 cm, 0.75 cm, and 1.00 cm, and an alternating Zig-zag pattern. Dosimetric parameters assessed included D90, V100%, and V200% for target volume coverage, and D0.2cc and D2cc for organs at risk (OARs), specifically the mandible, pharyngeal constrictor muscles (PCM), and right and left submandibular glands (SMGs). Surface dose was also evaluated to estimate mucosal toxicity risk. All data were analyzed using SPSS version 29. Normality tests were followed by Friedman and Wilcoxon signed-rank tests, as well as repeated measures ANOVA where appropriate. The 0.50 cm dwell activation strategy demonstrated the most favorable dosimetric profile, yielding the lowest mean surface dose (0.59 Gy) and mandible D0.2cc (1.56 Gy), while maintaining adequate tumor coverage (mean D90: 5.17 Gy; V100%: 99.64%). Although the Initial plan resulted in the highest D90 (5.82 Gy), it was associated with elevated surface and OAR doses. The Zig-zag pattern achieved comparable OAR sparing to the 0.50 cm configuration but exhibited higher inter-patient variability. Wider activation intervals (0.75 cm and 1.00 cm) did not improve tumor coverage and were linked to increased dose exposure to adjacent healthy structures. Statistically significant dose reductions were observed for the mandible and PCM using tighter dwell configurations (p < 0.05). Dwell position selection significantly influenced dose distribution in HDR tongue brachytherapy. Among the strategies evaluated, the 0.50 cm dwell spacing provided the most favorable balance between target coverage and OAR sparing, supporting its consideration as an optimal source loading pattern in clinical planning
A study of radiation dose from computed tomography (CT) simulation scan in brachytherapy treatment
No full textBrachytherapy is a form of internal radiation therapy that relies on precise imaging for accurate applicator placement and treatment planning. This study aimed to evaluate the radiation dose delivered during CT simulation scan for brachytherapy treatments involving liver, tongue, and endometrial cancers. Ensuring patient safety while maintaining image quality is essential, as excessive imaging doses contribute to overall radiation exposure. Method: A retrospective analysis was conducted on CT simulation scan parameters and dose metrics, including volume Computed Tomography Dose Index (CTDIvol) and Dose-length product (DLP), collected from 46 patients across the three treatment sites. The collected data were compared against international Diagnostic Reference Levels (DRLs) set at the 75th percentile to determine compliance. The CTDIvols for liver, tongue, and endometrial cancer were 46.42, 32.76, and 54.20 mGy, respectively. Meanwhile, DLP values for liver, tongue, and endometrial cancer were 1496.0 mGy.cm, 1893.1 mGy.cm, and 1585.5 mGy.cm, respectively. The data revealed that the majority of scans were under permissible dosage limits; liver, tongue, and endometrial cancer were 46.42 mGy, 32.76 mGy, and 54.20 mGy, respectively, while DLP values were 1496 mGy.cm, 1893.10 mGy.cm, and 1585.5 mGy.cm. However, instances of elevated CTDIvol and DLP were identified, particularly in endometrial cases due to thinner slice thickness and complex pelvic anatomy. In conclusion, this study highlights the need for continued monitoring and protocol optimisation to minimise unnecessary radiation exposure during CT simulation for brachytherapy, supporting the ALARA principle and promoting safe imaging practices
Bloodstain pattern analysis: examining the effect of wind blow on passive bloodstain pattern dropped from different heights
No full textBloodstain pattern analysis serves vitally in crime scene investigation by reconstructing the bloodshed events and providing information on the assailant, victim and crime nature. Passive bloodstain pattern enables the estimations of blood source’s height which could potentially correlate with the height of assailant or victim. However, a bloodletting crime occurring at outdoor environment introduces uncontrollable and unpredictable external factors such as wind blow which can interfere with the usual behaviour of blood leaving the body, hindering the correct interpretation of bloodstain evidence. Additionally, limited research has been done on the effect of wind blow on passive bloodstain pattern, especially when incorporating with different heights of blood source. This study aims to examine the effects of wind velocity and height of blood drop fall on the position shift and physical characteristics of passive blood drop stain, as well as how prolonged exposure to wind blow affect the stain’s physical appearance. In this study, a single drop of blood was gently dispensed from the pipette tip using a micropipette onto a smooth white floor tile under each combination of wind velocity category and fall height. The data obtained were statistically analysed using multiple linear regression. The findings showed that wind velocity and its combined effect with fall height caused increase in the horizontal (x) position shift for up to 15.70 cm but had no significant effect on the vertical (y) position shift. The shrinkage observed on majority of the bloodstains obliterated their original physical characteristics, hence no relationship was found between wind velocity and height of fall with width, length, width-to-length ratio, number of spines, number of satellite stains, angle of impact, and glancing angle. The bloodstain’s shape was found to be not distorted from sphericity much and no directionality was revealed on the stain when blood drop fell passively from 60 cm height across different categories of wind velocity. To conclude, this study demonstrates the unpredictable and distortable passive blood drop stain at outdoor environment and suggests careful consideration of wind blow and height of blood drop fall effects by the investigators when dealing with bloodstain evidence, especially at actual outdoor crime scene
Patient-doctor relationships and its associated factors perceived by patients at non govermental hemodialysis clinics in Malaysia
No full textBuilding strong patient-doctor relationships and effective communication are crucial for enhancing care quality and outcomes, particularly for hemodialysis patients. However, limited research exists on how these relationships impact patient outcomes in Malaysia, despite frequent interactions between hemodialysis patients and healthcare providers. This study aimed first to translate and validate the Malay versions of the Patient-Doctor Relationship Questionnaire and Doctor-Patient Communication Questionnaire, and subsequently to employ the validated tools to assess patient-doctor relationships and communication among hemodialysis patients in Malaysia. The study was conducted in two phases. In Phase I, expert panels translated and validated the PDRQ-9 and DPCQ into Malay. Cognitive debriefing involving eight hemodialysis care personnel and seven patients confirmed comprehensibility. Psychometric properties were assessed among 300 respondents using Confirmatory Factor Analysis (CFA) and internal consistency. The initialMyPDRQ demonstrated high internal consistency (Raykov’s rho=0.906), with CFA indices indicating good model fit (SRMR=0.025, RMSEA<0.001, CFI=1.000, TLI=1.000). The initialMyD-PCQ showed high reliability (Raykov’s rho=0.887) and good model fit (SRMR=0.037, RMSEA=0.029, CFI=0.982, TLI=0.979). In Phase II, a cross-sectional study using the validated MyPDRQ and MyD-PCQ was conducted among 640 hemodialysis patients across Malaysia. The majority were female (54.5%), aged 48 years or older (57.1%), Malay (47.0%), and married (58.8%). Nearly 60% had
an income below RM 4360. The mean patient-doctor relationship score was 35.40 (SD=7.74), and the mean doctor-patient communication score was 51.09 (SD=8.14). Communication emerged as the most significant factor associated with relationships (Adj β=1.163, p<0.001). Younger patients (18–27 years) scored lower (Adj β=-0.044, p=0.027), while higher education levels were positively associated with better scores (Adj β=0.034, p=0.023). Employment and income were not statistically significant. The MyPDRQ and MyD-PCQ are valid and reliable instruments, providing appropriate tools for assessing patient-doctor relationships and communication among Malaysian hemodialysis patients. These findings have important implications for policy, practice, and future research, as they support the integration of culturally adapted measures into routine clinical care, inform targeted interventions to enhance communication, and contribute evidence for strategies aimed at improving long-term patient satisfaction and clinical outcome