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Concept: Fingerprint


Each person expresses a potentially unique subset of ∼400 different olfactory receptor subtypes. Given that the receptors we express partially determine the odors we smell, it follows that each person may have a unique nose; to capture this, we devised a sensitive test of olfactory perception we termed the “olfactory fingerprint.” Olfactory fingerprints relied on matrices of perceived odorant similarity derived from descriptors applied to the odorants. We initially fingerprinted 89 individuals using 28 odors and 54 descriptors. We found that each person had a unique olfactory fingerprint (P < 10(-10)), which was odor specific but descriptor independent. We could identify individuals from this pool using randomly selected sets of 7 odors and 11 descriptors alone. Extrapolating from this data, we determined that using 34 odors and 35 descriptors we could individually identify each of the 7 billion people on earth. Olfactory perception, however, fluctuates over time, calling into question our proposed perceptual readout of presumably stable genetic makeup. To test whether fingerprints remain informative despite this temporal fluctuation, building on the linkage between olfactory receptors and HLA, we hypothesized that olfactory perception may relate to HLA. We obtained olfactory fingerprints and HLA typing for 130 individuals, and found that olfactory fingerprint matching using only four odorants was significantly related to HLA matching (P < 10(-4)), such that olfactory fingerprints can save 32% of HLA tests in a population screen (P < 10(-6)). In conclusion, a precise measure of olfactory perception reveals meaningful nonolfactory genetic information.

Concepts: Fingerprint, Sense, Body odor, Receptor, Olfactory receptor, Olfaction, Aroma compound, Odor


The performance of conventional minutiae-based fingerprint authentication algorithms degrades significantly when dealing with low quality fingerprints with lots of cuts or scratches. A similar degradation of the minutiae-based algorithms is observed when small overlapping areas appear because of the quite narrow width of the sensors. Based on the detection of minutiae, Scale Invariant Feature Transformation (SIFT) descriptors are employed to fulfill verification tasks in the above difficult scenarios. However, the original SIFT algorithm is not suitable for fingerprint because of: (1) the similar patterns of parallel ridges; and (2) high computational resource consumption. To enhance the efficiency and effectiveness of the algorithm for fingerprint verification, we propose a SIFT-based Minutia Descriptor (SMD) to improve the SIFT algorithm through image processing, descriptor extraction and matcher. A two-step fast matcher, named improved All Descriptor-Pair Matching (iADM), is also proposed to implement the 1:N verifications in real-time. Fingerprint Identification using SMD and iADM (FISiA) achieved a significant improvement with respect to accuracy in representative databases compared with the conventional minutiae-based method. The speed of FISiA also can meet real-time requirements.

Concepts: Algorithm, Fingerprint Verification Competition, Better, Biometrics, Scale-invariant feature transform, Computational complexity theory, Improve, Fingerprint


Recent publications have explored the possibility of using fingerprints to confirm drug use, but none has yet dealt with environmental contamination from fingertips. Here we explored the possibility of establishing an environmental cutoff for drug testing from a single fingerprint.

Concepts: Psychoactive drug, Fingerprint, Sherlock Holmes, Heroin, Single Convention on Narcotic Drugs, Methamphetamine, Drug injection, Drug addiction


Human identification by fingerprints is based on the fundamental premise that ridge patterns from distinct fingers are different (uniqueness) and a fingerprint pattern does not change over time (persistence). Although the uniqueness of fingerprints has been investigated by developing statistical models to estimate the probability of error in comparing two random samples of fingerprints, the persistence of fingerprints has remained a general belief based on only a few case studies. In this study, fingerprint match (similarity) scores are analyzed by multilevel statistical models with covariates such as time interval between two fingerprints in comparison, subject’s age, and fingerprint image quality. Longitudinal fingerprint records of 15,597 subjects are sampled from an operational fingerprint database such that each individual has at least five 10-print records over a minimum time span of 5 y. In regard to the persistence of fingerprints, the longitudinal analysis on a single (right index) finger demonstrates that (i) genuine match scores tend to significantly decrease when time interval between two fingerprints in comparison increases, whereas the change in impostor match scores is negligible; and (ii) fingerprint recognition accuracy at operational settings, nevertheless, tends to be stable as the time interval increases up to 12 y, the maximum time span in the dataset. However, the uncertainty of temporal stability of fingerprint recognition accuracy becomes substantially large if either of the two fingerprints being compared is of poor quality. The conclusions drawn from 10-finger fusion analysis coincide with the conclusions from single-finger analysis.

Concepts: Maxima and minima, Comparison, Tend, Longitudinal study, Fingerprint, Finger, Statistics, Sociology


The development of effective sediment management strategies is a key requirement in tropical areas with fast urban development, like Brasilia DF, Brazil, because of the limited resources available. Accurate identification and management of sediment sources areas, however, is hampered by the dearth of reliable information on the primary sources of sediment. Few studies have attempted to quantify the source of sediment within fast urbanizing, mixed used, tropical catchments. In this study, statistically verified composite fingerprints and a multivariate mixing model have been used to identify the main land use specific sources of sediment deposited in the artificial Lago Paranoá, Central Brazil. Because of the variability of urban land use types within the Lago Paranoá sub-catchments, the fingerprinting approach was additionally undertaking for the Riacho Fundo sub-catchment. The main contributions from individual source types (i.e. surface materials from residential areas, constructions sites, road deposited sediment, cultivated areas, pasture, farm tracks, woodland and natural gullies) varied between the whole catchment and the Riacho Fundo sub-catchment, reflecting the different proportions of land uses. The sediments deposited in the silting zones of the Lago Paranoá originate largely from urban sources (85±4%). Areas with (semi-) natural vegetation and natural gullies contribute 10±2% of the sediment yield. Agricultural sites have only a minor sediment contribution of about 5±4% within the whole catchment. Within the Riacho Fundo sub-catchment there is a significant contribution from urban (53±4%) source, such as residential areas with semi-detached housings (42±3%) with unpaved roads (12±3%) and construction sites (20±3%) and agricultural areas (31±2%). The relative contribution from land use specific sources to the sediment deposition in the silting zone of the Lago Paranoá demonstrated that most of the sediment is derived from sites with high anthropogenic impact.

Concepts: Drainage basin, Fingerprint, Urban planning, Source, Erosion, Land use planning, Sediment, Land use


INTRODUCTION: The fruits of Vaccinium vitis-idaea L. are a valuable source of biologically active flavonoid derivatives. For studies focused on the purification of its quercetin glycosides (QGs) and related glycosides from plants and for the purpose of biological studies, the availability of numeric datasets from computer-assisted (1) H iterative full spin analysis (HiFSA), that is, (1) H-NMR fingerprinting, can replace and assist the repetitive and tedious two-dimensional NMR identification protocol required for both known and new compounds, respectively. OBJECTIVE: To fully interpret the complex (1) H-NMR fingerprints of eight QGs obtained from the berries of V. vitis-idaea and provide complete and unambiguous signal assignments. METHODS: Vaccinium vitis-idaea QGs were purified in a single run by long-bed gel permeation chromatography and identified by comparison with commercially available compounds using LC-MS combining ion-trap and time-of-flight detection and one- or two-dimensional NMR. The HiFSA analysis yielded full sets of (1) H chemical shifts and proton-proton coupling constants, allowing for field-independent spectral simulation. RESULTS: Signal assignments were achieved for the reference standards and the QGs that dominated in purified fractions. However, even mixtures of two to three QGs could be fitted using the HiFSA approach. In the case of the overlapped sugar resonances, the initial fitting of the (1) H spectra of reference compounds, together with values extracted from the two-dimensional NMR data and literature data, assisted in the process. CONCLUSION: The HiFSA method revealed for the first time the presence of Q-3-O-β-glucopyranoside and Q-3-O-β-glucuronopyranoside in the berries of V. vitis-idaea, and unambiguously confirmed the structures of Q-3-O-[4″-(3-hydroxy-3-methylglutaroyl)]-α-rhamnopyranoside, Q-3-O-α-rhamnopyranoside, Q-3-O-β-galactopyranoside, Q-3-O-α-arabinofuranoside, Q-3-O-β-xylopyranoside and Q-3-O-α-arabinopyranoside. Copyright © 2013 John Wiley & Sons, Ltd.

Concepts: Flavonols, Fingerprint, Chemical compound, John Wiley & Sons, Quercetin, Fruit, Biology, Vaccinium vitis-idaea


Latent fingerprints provide a potential route to the secure, high throughput and non-invasive detection of drugs of abuse. In this study we show for the first time that the excreted metabolites of drugs of abuse can be detected in fingerprints using ambient mass spectrometry. Fingerprints and oral fluid were taken from patients attending a drug and alcohol treatment service. Gas chromatography mass spectrometry (GC-MS) was used to test the oral fluid of patients for the presence of cocaine and benzoylecgonine. The corresponding fingerprints were analysed using Desorption Electrospray Ionization (DESI) which operates under ambient conditions and Ion Mobility Tandem Mass Spectrometry Matrix Assisted Laser Desorption Ionization (MALDI-IMS-MS/MS) and Secondary Ion Mass Spectrometry (SIMS). The detection of cocaine, benzoylecgonine (BZE) and methylecgonine (EME) in latent fingerprints using both DESI and MALDI showed good correlation with oral fluid testing. The sensitivity of SIMS was found to be insufficient for this application. These results provide exciting opportunities for the use of fingerprints as a new sampling medium for secure, non-invasive drug detection. The mass spectrometry techniques used here offer a high level of selectivity and consume only a small area of a single fingerprint, allowing repeat and high throughput analyses of a single sample.

Concepts: Tandem mass spectrometry, Fingerprint, Gas chromatography-mass spectrometry, Desorption electrospray ionization, Drug addiction, Electrospray ionization, Ion source, Mass spectrometry


The majority of anthropological studies on dermatoglyphics examine the heritability and inter-population variation of Level 1 detail (e.g., pattern type, total ridge count), while forensic scientists concentrate on individual uniqueness of Level 2 and 3 detail (e.g., minutiae and pores, respectively) used for positive identification. The present study bridges the gap between researcher-practitioner by examining sex, ancestral, and pattern type variation of Level 2 detail (e.g., minutiae).

Concepts: Profiling practices, First-order logic, Cultural studies, Minutiae, Sherlock Holmes, Forensic science, Genetics, Fingerprint


In the past century, forensic investigators have universally accepted fingerprinting as a reliable identification method, which relies mainly on pictorial comparisons. Despite developments to software systems in order to increase the probability and speed of identification, there has been limited success in the efforts that have been made to move away from the discipline’s absolute dependence on the existence of a prerecorded matching fingerprint. Here, we have revealed that an information-rich latent fingerprint has not been used to its full potential, as the content, in our approach namely the amino acids, present in the sweat left behind - can be used to determine physical attributes, such as gender, of the originator. Here, we are able to focus on the biochemical content in the fingerprint using a specially designed extraction protocol coupled with a biocatalytic assay for determining gender rather than focusing solely on the physical image.

Concepts: Amino acid, International Association for Identification, Sherlock Holmes, Forensic science, Fingerprint


Fingerprints can be of tremendous value for forensic biology, since they can be collected from a wide variety of evident types, such as handles of weapons, tools collected in criminal cases, and objects with no apparent staining. DNA obtained from fingerprints varies greatly in quality and quantity, which ultimately affects the quality of the resulting STR profiles. Additional difficulties can arise when fingerprint samples show mixed STR profiles due to the handling of multiple persons. After applying a tested protocol for sample collection (swabbing with 5% Triton X-100), DNA extraction (using an enzyme that works at elevated temperatures), and PCR amplification (AmpFlSTR® Identifiler® using 31cycles) extensive analysis was performed to better understand the challenges inherent to fingerprint samples, with the ultimate goal of developing valuable profiles (≥50% complete). The impact of time on deposited fingerprints was investigated, revealing that while the quality of profiles deteriorated, full STR profiles could still be obtained from samples after 40days of storage at room temperature. By comparing the STR profiles from fingerprints of the dominant versus the non-dominant hand, we found a slightly better quality from the non-dominant hand, which was not always significant. Substrates seem to have greater effects on fingerprints. Tests on glass, plastic, paper and metal (US Quarter dollar, made of Cu and Ni), common substrates in offices and homes, showed best results for glass, followed by plastic and paper, while almost no profiles were obtained from a Quarter dollar. Important for forensic casework, we also assessed three-person mixtures of touched fingerprint samples. Unlike routinely used approaches for sampling evidence, the surface of an object (bottle) was sectioned into six equal parts and separate samples were taken from each section. The samples were processed separately for DNA extraction and STR amplification. The results included a few single source profiles and distinguishable two person mixtures. On average, this approach led to two profiles ≥50% complete per touched object. Some STR profiles were obtained more than once thereby increasing the confidence.

Concepts: Biology, Fingerprint, Identification, DNA profiling, Enzyme, Polymerase chain reaction, Molecular biology, DNA