The Study of Morphologieal Features of Spermatozoa under Ditl'erent Temperature by Seanning Electron Microscope

Semen is the body fluid frequently found in sexual crimes. It is principally comprised of spermatozoa suspended in seminal plasma Spermatozoa with distinct and characteristic appearance can be detected and confinned microscopically. In this study, the morphological features of spermatozoa under different temperature exposures were observed and examined by scanning electron microscope which was greatly used for the observation of discrete cell surfaces in three dimensional views at high magnification. 10 samples collected at Cytology section of Pathology Laboratory, Hospital Universiti Sains Malaysia, were divided into three different portions and kept into three different temperatures, including 55°C, 4°C and room temperature for a 5 day period. All the samples were observed by scanning electron microscope after exposure to respective temperature. Different scores were given to varied morphological features of spermatozoa observed. Through the scoring of morphological features, statistical analysis was conducted for the determination of any significant change. Result of the examination showed significant difference in the morphological features of spermatozoa for both the experimental samples as compared to the control samples. After the high temperature exposure on the samples, significant changes in the shape and surface of the bead, acrosome morphology and mid-piece of spermatozoa were found Tapered end head was seen on heat exposure. In addition, depressions and fossa were found on the surface of the head with damaged acrosome morphology. Bent mid-piece of spennatozoa was also significantly observed with high temperature exposure. On the other hand, significant changes were found with the samples on cooling. Tail and mid-piece of spermatozoa differed significantly with control samples on exposure to low temperature. Hair-pinned and severe coiled tails of spermatozoa were found in cooled samples. Mid-piece of spermatozoa was also disrupted with thinning and bending on low temperature exposure. Differences in the morphological features of spermatozoa on exposure to different temperature can be used as a tool to establish the condition of a sexual crime scene

A survey on vehicle registration code: association between on-the- road population and their vehicle registration states

Every registered vehicle in Malaysia has a specific vehicle registration code consisting of alphabets and numbers displayed on the front and rear part of the vehicle. Whenever there is an incident related to a particular vehicle, this registration code can be used to retrieve information about the vehicle based on the data in the registry maintained by Malaysian Road Transport Department. The information can subsequently assist in tracing the motor vehicle and its owner or to assess witness’s statement. However, our current vehicle registration system in Malaysia that uses alphabets to represent different territories or states could raise difficulties during an investigation especially if the registration number on the car plate could not be identified confidently by a witness whether or not the registration code in questioned could have from a particular state and involved in the incident under investigation. Therefore, the distribution of car registration code in Kelantan state was investigated, aiming to estimate the frequency of locally registered vehicle compared to those registered in other states of Malaysia as indicated by the alphabets. In this study, two car parking areas, one designated for general public and the other for university staff, were chosen (n=1000), surveyed and statistically analysed. Frequency and percentage in term of state of registration reflected by the initial alphabet for respective car parks were evaluated. Pearson’s Chi Square (χ2) test was used to investigate if there is association between the two car parks based on plate numbers with “D” which indicate those cars registered in Kelantan, and cars with non-“D” plates that pertain to the other states. Our study shows higher percentage of vehicles carrying “D” (515, 51.5%) and “W” (234, 23.4%) plates in the study area. Statistical test suggests no significant association between the two car parks and “D” plated cars (p-value=0.067, >0.05), supporting the claim that the majority of the residents own cars registered in Kelantan state, regardless of their state of origin. For forensic intelligence, information from this study could strengthen the probative opinion and forensic significance when exploring information based on vehicle registration code, particularly in cases involving vehicles

Forensic discrimination of blue pen inks: emergence of hybrid pen inks

Pens are frequently used to make alterations to documents during forgery. Comparing to conventional inks, hybrid pen ink brings a different challenge to forensic document examiners in differentiating ink entries on a questioned document. Therefore, this study aims to investigate the characteristics of different blue pen inks using non-destructive approaches followed by destructive techniques. Twenty blue pens consisting of ten ballpoint pens and ten gel pens of various brands were subjected to microscopic examination, video spectral comparator examination, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, and thin layer chromatography (TLC) using two different solvent systems. The microscopic examination showed significant different optical features on handwritten samples produced by ballpoint and gel pens. Luminescence behaviour of certain inks allowed discrimination, and ATR-FTIR coupled with principal component analysis clustered ink samples of similar compositional profiles in a score plot. TLC allowed further discrimination of ink samples from ballpoint and hybrid pens. The proposed analysis scheme had categorised the ink samples into 11 groups. To conclude, the hybrid pen labelled as gel pen appeared optically like gel pen. However, it possesses chemical characteristics similar to a ballpoint pen. Therefore, its emergence deserves attention during forensic questioned document examination, particularly for the determination of pen inks

Inter-rater reliability of vehicle color perception for forensic intelligence

The topcoat color of motor vehicles offers vital information while investigating vehicular accidents, especially in instance of hit-and-run, since witnesses seldom perceive and retain the plate details. Differences in color perceptions among individuals with normal vision may lead to confusion in determining the color of the car involved. In this way, witnesses of crash accidents could potentially initiate flawed leads in forensic investigation, and thus affect the administration of justice. In this study, the inter-rater reliability of vehicle color determination by different volunteers was explored. Six individuals observed the topcoat colors of 500 stationary and 500 moving vehicles from five locations, employing a common system of color gradation. The outcome was binary: the vehicle color was either a “match” or “non-match”. This was followed by statistical analysis in terms of the colors’ frequencies and inter-rater reliability, based on which more suitable color descriptions were determined for subsequent comparisons of stationary and moving vehicles. Higher match frequencies and greater interrater reliability were observed when color gradations were disregarded. The frequency of correct matches could have been closely related to their relative on-the-road distribution, regardless of the statuses of observed vehicles. It was also found that black and white were associated with a greater number of matches than were intermediate colors, which should be carefully interpreted during forensic investigation to avoid wrong leads. In conclusion, the present study demonstrated the forensic significance of vehicle topcoat color determination, particularly in cases where witness statements are crucial

Visualization of methamphetamine-contaminated fingermarks on glass surfaces by field emission scanning electron microscope for forensic investigation

Background: Fingermark is an individual's primary identification source. It is helpful in determining individuals involved in illegal activities and is frequently encountered in clandestine laboratories. During forensic investigation, the critical question to be answered is whether a fingermark was left on a surface before or after the initiation of an unlawful activity. Aims and Objectives: This study aimed to investigate the visualization of methamphetamine-contaminated fingermarks on glass surfaces and estimate the immediacy of their depositions. Materials and Methods: In this study, the prior-deposition contaminated fingermarks, i.e., fingermarks deposited a surface priorly contaminated by methamphetamine, and the postdeposition contaminated fingermarks, i.e., fingermarks deposited on a clean surface but subsequently contaminated with methamphetamine were visualized and compared using Field Emission Scanning Electron Microscope (FESEM). Results: Under FESEM, the latent fingermarks and the crystalline structure of methamphetamine were clearly visualized. The postdeposition contaminated fingermarks appeared in smudge conditions in all the three replicate samples, where the ridge and nonridge areas could not be well-distinguished. On the contrary, the prior-deposition contaminated fingermark demonstrated distinct separations between ridges and nonridges. However, the application of fingerprint powders reduced the possibility to determine the immediacy of deposition. Conclusion: To conclude, both prior-deposition contaminated fingermarks and postdeposition contaminated fingermarks can be discriminated, providing information on the instance when a fingermark was left on a surface

An exploratory study on the handwritten allographic features of multi-ethnic population with different educational backgrounds

Ethnicity, native and/or foreign language knowledge, as well as the learned writing systems potentially influence the development of an individual’s handwriting. The unique education system consisting of National schools, Chinese-medium vernacular schools, Tamil-medium vernacular schools, and Islamic religious schools in Malaysia may have established specific characteristic handwritten allographic features that deserve investigation within the intelligence context. This study was aimed to explore handwritten allographic features of handwriting samples from 120 subjects (30 writers from four different educational backgrounds mentioned above). Characteristic features which could be attributed to the study groups were statistically analyzed and identified. In this study, thirteen allographic features, including letters "A", "B", "D", "H", "p", "T", "t", "w", "X" and "x", were found to be discriminative. Such information could serve to indicate the primary education system undergone by a writer; enabling the comparison of different handwriting profiles and allowing characterization of writers to a specific group of people

A Fabrication of Multichannel Graphite Electrode Using Low-Cost Stencil-Printing Technique

Multichannel graphite electrodes (MGrEs) have been designed and fabricated in this study. A template was cut from an adhesive plastic sheet using a desktop cutting device. The template was placed on a polypropylene substrate, and carbon graphite ink was applied with a squeegee to the template. The size of the auxiliary electrode (AE) as well as the location of the reference electrode (RE) of MGrEs design were investigated. Scanning electron microscopy was used to determine the thickness of the ink on the four working electrodes (WEs), which was 21.9 ± 1.8 µm. Cyclic voltammetry with a redox probe solution was used to assess the precision of the four WEs. The intra-electrode repeatability and inter-electrode reproducibility of the MGrEs production were satisfied by low RSD (<6%). Therefore, the MGrEs is reliable and capable of detecting four replicates of the target analyte in a single analysis. The electrochemical performance of four WEs was investigated and compared to one WE. The sensitivity of the MGrEs was comparable to the sensitivity of a single WE. The MGrEs’ potential applications were investigated by analyzing the nitrite in milk and tap water samples (recoveries values of 97.6 ± 0.4 to 110 ± 2%)

Temporal association of maternal weight gain with early-term and preterm birth and low birth weight babies

Background: Low birth weight and preterm or early-term babies may have a higher risk of poor health. One of the main factors is the weight gain of a pregnant woman during gestational weeks in the second and third trimesters. Changes in weight over a month in a pregnant woman might also have an impact on infant outcomes. This study aimed to investigate the association between maternal weight at different time points and low birth weight and preterm or early-term babies (premature babies). Methods: A total of 156 pregnant women were recruited. Maternal weight was collected at different gestational weeks. Maternal age, body mass index, delivery mode, delivery week, and infant weight were also recorded. Maternal data were restructured into a person-period format before mixed-effects multiple logistic regression was used. Various weight variables with either a fixed effect or time-varying effects were tested in the model. Results: Thirty (19.23%) women had delivered low birth weight or premature babies. Multiple logistic regression model demonstrated that mothers with higher increases in weight at 32 weeks of gestation than that in the predelivery stage had a lower probability of having a low birth weight or premature baby (odds ratio [OR] = 0.64; 95% CI, 0.49-0.85; p < 0.001). Women with a weight increase of more than 2 kg in a 4-week gestation period had a higher probability of having a low birth weight or premature baby than those with an increment of <1 kg (OR = 8.43; 95% CI, 2.90-24.54; p < 0.001). Conclusion: An increase in weight gain after 32 weeks was shown to reduce the risk of low birth weight and premature babies. Maternal weight monitoring was suggested to be conducted every 4 weeks to minimize the chance of having a low birth weight and premature baby

Temporal association of maternal weight gain with early-term and preterm birth and low birth weight babies

Background: Low birth weight and preterm or early-term babies may have a higher risk of poor health. One of the main factors is the weight gain of a pregnant woman during gestational weeks in the second and third trimesters. Changes in weight over a month in a pregnant woman might also have an impact on infant outcomes. This study aimed to investigate the association between maternal weight at different time points and low birth weight and preterm or early-term babies (premature babies). Methods: A total of 156 pregnant women were recruited. Maternal weight was collected at different gestational weeks. Maternal age, body mass index, delivery mode, delivery week, and infant weight were also recorded. Maternal data were restructured into a person-period format before mixed-effects multiple logistic regression was used. Various weight variables with either a fixed effect or time-varying effects were tested in the model. Results: Thirty (19.23%) women had delivered low birth weight or premature babies. Multiple logistic regression model demonstrated that mothers with higher increases in weight at 32 weeks of gestation than that in the predelivery stage had a lower probability of having a low birth weight or premature baby (odds ratio [OR] = 0.64; 95% CI, 0.49-0.85; p < 0.001). Women with a weight increase of more than 2 kg in a 4-week gestation period had a higher probability of having a low birth weight or premature baby than those with an increment of <1 kg (OR = 8.43; 95% CI, 2.90-24.54; p < 0.001). Conclusion: An increase in weight gain after 32 weeks was shown to reduce the risk of low birth weight and premature babies. Maternal weight monitoring was suggested to be conducted every 4 weeks to minimize the chance of having a low birth weight and premature baby

A Fabrication of Multichannel Graphite Electrode Using Low-Cost Stencil-Printing Technique

Multichannel graphite electrodes (MGrEs) have been designed and fabricated in this study. A template was cut from an adhesive plastic sheet using a desktop cutting device. The template was placed on a polypropylene substrate, and carbon graphite ink was applied with a squeegee to the template. The size of the auxiliary electrode (AE) as well as the location of the reference electrode (RE) of MGrEs design were investigated. Scanning electron microscopy was used to determine the thickness of the ink on the four working electrodes (WEs), which was 21.9 &plusmn; 1.8 &micro;m. Cyclic voltammetry with a redox probe solution was used to assess the precision of the four WEs. The intra-electrode repeatability and inter-electrode reproducibility of the MGrEs production were satisfied by low RSD (&lt;6%). Therefore, the MGrEs is reliable and capable of detecting four replicates of the target analyte in a single analysis. The electrochemical performance of four WEs was investigated and compared to one WE. The sensitivity of the MGrEs was comparable to the sensitivity of a single WE. The MGrEs&rsquo; potential applications were investigated by analyzing the nitrite in milk and tap water samples (recoveries values of 97.6 &plusmn; 0.4 to 110 &plusmn; 2%)