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Background: Hair is one of the most frequently encountered trace evidence in crime scenes. It has been used for differentiating races or identifying species of animals. An understanding of intra-and inter-variation of human scalp hair may enable discrimination based on ethnicity. This study aims to discriminate the ethnic Malays and ethnic Chinese in Malaysia based on three morphometric measurements of the human scalp hair. Method: The sample group was composed of 100 Malaysians, 50 each (i.e. 25 males and 25 females) from ethnic Malays and ethnic Chinese. Each subject has provided 20 strands of hair. The hair width (HW), scale layer difference (SLD), and medullary index (MI) of each hair were determined using a compound microscope. Following that, the inter-variation of hair was evaluated according to (a) head regions, (b) sex, and (c) ethnic groups and assessed using descriptive and inferential statistics, i.e. independent t test and Wilcoxon's rank-sum test. Results: Results show that Malays and Chinese are different in all the three morphometries. However, Malay males are different from females only in terms of SLD, and Chinese males and females could be discriminated using MI. Next, hair originating from upper and lower head regions, regardless of ethnicity and sex, are not significantly different. Conclusion: In conclusion, Malays and Chinese could be discriminated based on morphometric measurements of scalp hair. The finding sheds new light on the feasibility of differentiating ethnic groups using physical measurements alone.

Ultra-performance liquid chromatography (UPLC) is more effective than high performance liquid chromatography in terms of analysis speed and sensitivity. This paper presents a feasibility study on forensic red pen inks analysis using UPLC. A total of 12 varieties of red ballpoint pen inks were purchased from selected stationary shop. For each variety, four different individual pens were sampled to provide intra-variability within a particular variety of pen. The proposed approach is very simple that it only involved limited analysis step and chemicals. A total of 144 chromatograms were obtained from red ink entries extracted with 1.5 mL 80 % (v/v) acetonitrile. Peaks originated from pen inks were determined by comparing the chromatograms of both blank paper and blank solvent against that of ink samples. Subsequently, one-way ANOVA was conducted to discriminate all 66 possible pairs for red pen inks. Results showed that the proposed approach giving discriminating power of 95.45 %. The outcome of the study indicates that UPLC could be a fast and simple approach to red ballpoint pen inks analysis.Keywords: forensic ink analysis, ballpoint pen inks, ultra-performance liquid chromatography Abstrak Kromatografi cecair berprestasi Ultra (UPLC) adalah lebih berkesan dari kromatografi cecair berprestasi tinggi dari segi kelajuan analisis dan kepekaan. Kertas ini mempersembahkan kajian kebolehlaksanaan pada analisis dakwat pen merah menggunakan UPLC. Sebanyak 12 jenis dakwat pen mata bulat merah dibeli dari kedai alat tulis yang terpilih. Untuk setiap jenis, empat batang pen telah disampel untuk memberi maklumat tentang intra-variasi bagi suatu jenis pen. Pendekatan yang dicadangkan adalah mudah kerana ia hanya melibatkan langkah analisis dan bahan kimia yang terhad. Sejumlah 144 kromatogram telah diperolehi dari dakwat tulisan merah yang diekstrak dengan 1.5 mL 80 % (v/v) asetonitril. Puncak yang berasal dari dakwat pen ditentukan melalui perbandingan antara kromatogram kertas kosong dan pelarut kosong dengan yang diperolehi dari sampel dakwat. Seterusnya, ujian ANOVA sehala telah dijalankan untuk membezalayan kesemua 66 pasangan dakwat pen merah yang terbentuk. Keputusan menunjukkan pendekatan yang dicadangkan memberi 95.45 % kuasa pembezalayan. Hasil kajian ini menunjukkan UPLC dapat dijadikan satu pendekatan yang cepat dan mudah untuk analisis dakwat pen mata bulat merah.