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1.
Poaching is a crime that occurs worldwide and can be extremely difficult to investigate and prosecute due to the nature of the evidence available. If a species is protected by international legislation such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora then simply possessing any part of that species is illegal. Previous studies have focused on the identification of endangered species in cases of potential poaching. Difficulties arise if the poached animal is not endangered. Species such as deer have hunting seasons whereby they can legally be hunted however poaching is the illegal take of deer, irrespective of season. Therefore, identification of deer alone has little probative value as samples could have originated from legal hunting activities in season. After a deer is hunted it is usual to remove the innards, head and lower limbs. The limbs are removed through manual force and represent a potential source of human touch DNA.We investigate the potential to recover and profile human autosomal DNA from poached deer remains. Samples from the legs of ten culled deer were obtained (40 in total) using minitapes. DNA from samples was extracted, quantified and amplified to determine if it would be possible to recover human STR profiles.Low quantification data led to the use of an extended PCR cycling protocol of 34 cycles. Samples from seven deer amplified, however some samples were excluded from further analysis due to ‘drop in’ alleles or the low level of successfully amplified loci. Samples from five deer could be further analysed and gave match probabilities ranging from 6.37 × 10− 3 to 9.53 × 10− 11.This study demonstrates the potential of recovering human touch DNA from poached animal remains. There is the potential for this test to be used in relation to other species of poached remains or other types of wildlife crimes. This is the first time, to our knowledge, that human STR profiling has been successfully applied to touch DNA in regards to simulated wildlife crime.  相似文献   

2.
Abstract

The British Deer Society places the number of poached deer in the UK as high as 50,000 each year whereas only 335 incidents were reported to the police in 2009. This article explores deer as invisible victims of green crime and the motivations behind this poaching, drawing on the typologies of wildlife crime offenders developed by Nurse in 2013. In particular, the traditional profit-driven motivation of offenders is explored by attempting to uncover if there is, as suspected, a black market in venison. In order to do this, online questionnaires were sent to wildlife crime officers and gamekeepers asking questions about the scale and scope of deer poaching, who the perpetrators are and what is happening to the meat. From these data, it is hoped that a more detailed picture of deer poaching can be developed to further inform wildlife law and poaching prevention. This article also draws attention to the plight of poached deer and the potential danger to people of a black market in venison.  相似文献   

3.
Allele frequency distributions for 24 short tandem repeat (STR) loci were determined using the PowerPlexR Fusion System (Promega) in 407 Japanese samples. The most informative locus among the 22 STR loci, excluding Amelogenin and DYS391, was Penta E (power of discrimination (PD) = 0.98), while the least informative was TPOX(PD = 0.831). The 22 loci combined matching probability (MP) was calculated to be 4.13 × 10−26. These parameters indicated the usefulness of this 24 STR analysis in forensic personal identification and parentage testing among Japanese population.  相似文献   

4.
A continual challenge in the field of forensic DNA analysis is the amplification and interpretation of degraded and low-copy number (LCN) DNA obtained from amounts of limited biological evidence. It has been well established that DNA profiles obtained from the amplification of low quality, degraded, and/or LCN DNA samples are often of limited value due to the frequent occurrence of preferential amplification during polymerase chain reaction (PCR). The by-products of preferential PCR amplification are often observed as inter- and intra-locus peak imbalance, allelic dropout, and/or locus dropout. These are all artifacts that are identified during the interpretation phase of analysis rather than by improving the quality of the DNA present. While it is theoretically possible to obtain a complete DNA profile from a single cell, in reality, profiles obtained from suboptimal amounts of DNA are difficult to interpret and frequently inconsistent when replicated. Inspired by advances in next-generation sequencing techniques, we propose a methodology for simultaneously normalizing the abundance of PCR products across all short tandem repeat (STR) loci using the DNA exonuclease, duplex-specific nuclease (DSN). DSN is an enzyme isolated from the hepatopancreas of Red King (Kamchatka) crab that possesses a strong affinity for digesting double stranded DNA (dsDNA) and has limited activity toward single stranded DNA (ssDNA). Degraded DNA known to display peak imbalance and allele dropout was amplified using AmpFlSTR® Identifiler® Plus for 28 cycles. Following amplification, samples were denatured at 99.9 °C for 5 min and incubated with one unit of DSN at 62 °C in a 28 μl volume for 1 min. Nuclease activity was terminated through the addition of equal volume of 10 mM EDTA and 95 °C incubation for 2 min. Following DSN treatment, 21 of 30 alleles within the known profile exhibited some improvement in peak height balance. The findings obtained support the potential use of DSN treatment as a method for normalizing STR profiles and improving the quality of data from degraded and low quantity DNA samples.  相似文献   

5.
The analysis of degraded DNA is one of the biggest challenges in forensic casework. SNPs, which can be amplified using small amplicons, have previously been successfully applied to the profiling of forensic evidence that could not be analyzed using conventional STRs. Here we selected the 52 SNPforID SNP markers, with amplicons that ranged in size from 59 bp to 115 bp, and used them to profile a range of casework samples from Malaysia. DNA degradation is a common problem in Malaysia due to the high temperatures and humidity. To carry out the study we modified the 52 SNPforID markers into four 13-plex SNaPshot assays to enable easier interpretation of profiles on the ABI PRISM® 310 and 3500.Fifty-one crime samples comprising bloodstains on cloth, swabs, and a mat and 2 swabs of trace DNA from 10 crime scenes in Malaysia were profiled after DNA extraction using a phenol–chloroform method. The samples were also subjected to STR analysis using the Powerplex® 16 system (Promega), which resulted in only 17 full profiles and 9 partial profiles; using SNPs, 36 full profiles and 5 partial profiles could be generated.  相似文献   

6.
Recently, different portable hand-held and battery-powered dental X-ray units have become available. Especially for forensic odontological purposes, they offer diverse advantages such as for use in disaster areas and crime-scene locations as also in autopsy rooms and mortuaries. For any application, the most important feature of these hand-held devices is the delivered image quality. The aim of this study is to evaluate the radiographic image quality acquired by two portable X-ray devices in combination with two types of image receptors and to compare the findings with the image quality of a standard intra-oral X-ray device.Eleven samples consisting of eight teeth, two dry skeletal specimens and one formalin-fixed mandible part were mounted on blocks for standardised (re)positioning. Radiological images were acquired with two hand-held (AnyRay® 60 kVp, 0.02–4.00 mAs and NOMAD® 60 kVp, 0.023–2.277 mAs) and one wall-mounted (MinRay® 60/70 kVp 0.14–22.4 mAs) X-ray device combined with two image receptor systems (VistaScan® phosphor storage plate (PSP) and SIGMA® M CMOS Active Pixel technology sensor). The effect of X-ray source-to-object distance (SOD) was checked at 20 cm in conjunction with object to image receptor distances (OIDs) of 0.8 and 2.5 cm. For each parameter setup, the exposure times were run from low till high. An expert consent statement was achieved by agreement of four expert observers selecting the optimal images based on a developed four point quality rating system. Next, a selection of the images was assembled in a set of 198 observation screens and scored by seven observers. The observation screens were designed to compare observer scores, relations between devices, receptors and OIDs and images obtained from the different devices at equal exposure levels (mAs). All results were statistically analysed.Radiological image quality was significantly higher for phosphor plate compared with the CMOS digital receptor system (p < 0.0001). Furthermore, a significantly superior image quality was obtained for OID = 0.8 than for OID = 2.5 (p = 0.039). A significant difference in image quality between the three devices was also established (p = 0.02). The present study demonstrated the feasibility of portable X-ray systems for forensic odontological applications based on rendering optimal image quality, provided an in vitro guideline of optimal parameter settings and offered a radiological image database usable in further research.  相似文献   

7.
This work evaluates cocaine purity and the concentration ranges of adulterants and inorganic constituents for 31 street cocaine samples seized in two different regions of Brazil from July 2008 to May 2010. Cocaine and adulterants, such as caffeine, lidocaine and benzocaine, were quantified by Gas chromatography–mass spectrometry (GC–MS), and the inorganic constituents were determined by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and ion chromatography (IC). The cocaine concentrations in the samples seized in the Amazonas state (AM samples) ranged from 154 to 978 mg g? 1, and these samples did not contain any of the adulterants studied. The cocaine concentrations in the samples seized in the Minas Gerais state (MG samples) ranged from 63.9 to 753 mg g? 1. Caffeine was the main adulterant found in 76% of the MG samples, ranging in concentration from 5.5 to 645.3 mg g? 1. Lidocaine was found in 66.7% of the MG samples, with concentrations ranging from 16.3 to 576.7 mg g? 1. Benzocaine was found in only one MG sample, at a concentration of 84.8 mg g? 1. Fourteen elements were identified by ICP-OES, and a wide variation was observed in the concentrations of Ca, Mg, Na, P, Al, Fe, Mn and Zn. Pearson Product–moment Correlations between the analytes allowed the constituents to be associated with the chemicals used in the manufacturing of cocaine and with some common diluents. The study of the purity of cocaine and the presence and concentration of adulterants and inorganic constituents is important because the latter can have deleterious effects on health.  相似文献   

8.
Soil analysis is a valuable resource in forensic investigation. Classical forensic soil analysis involves examination of its physical characteristics and chemical composition, such as soil type, colour, particle size, shape, pH, elemental, mineral and organic content. However the limited variability of these parameters is not always allowing adequate discrimination between soil samples. As soil supports extreme diversity of microorganisms and eukaryotic communities, microbiological approaches have been proposed. Several molecular approaches for microbial DNA profiling are available; however there is a lack of published data of implementation of the next generation sequencing (NGS) approaches for forensic soil analysis.The aim of the current study was elaboration of criteria for soil metagenome data management and database searching. We used our previously sequenced collection of 11 samples collected from different environments (forests, fields, grasslands, urban park) with different flora. The single sample collection includes 9 soil samples per one sampling area (30 m × 30 m) spaced by 15 m. In the current study we concentrated mainly on 18S rRNA gene V2-V3 region for fungi however SSU rRNA region for arbuscular mycorrhizal (AMF) fungi and V2-V3 hypervariable region of 16S rRNA gene for bacterial communities were taken into account. The sequencing was performed by Roche/454 platform. For data analysis OTU based approach on mothur software and NCBI BLASTN search were used. NCBI BLASTN analysis revealed altogether 2983 AMF matches and 8997 18S matches as well as 25477 OTUs (16S) were determined. Several data filtration approaches were used for data management. We found that 18S marker results could be used to create and run a filtered database that is computationally much more efficient and flexible. Our results have broad impact; however more samples have to be analysed, additional studies performed and cooperation between soil scientists and forensic scientists is required to be able to implement these novel techniques into the routine forensic practice.  相似文献   

9.
《Science & justice》2014,54(6):451-458
Textile fibres were transferred to the hands of ten living subjects and their persistence was determined after hand washing. Average number of fibres transferred was 300 ± 133 (female 288 ± 92, male 311 ± 163) per 100 cm2 hand area in the 100 experiments. However the number of fibres transferred was not gender dependent but individual dependent. The hand texture of subjects was compared with the number of fibres transferred but the relationship was not observed. The number of fibres transferred varied significantly for the 10 repeated experiments performed under the same conditions for the same subject.The subjects were then asked to wash their hands with water. One test group washed their hands with standing water, and the other with running tap water. Afterwards, the number of fibres remaining on the test subjects' hands were investigated. Migration of the fibres on the surface of the observed hands did occur but total loss of transferred fibre after hand washing did not occur. The average number of fibres remaining per 100 cm2 hand area was 14 ± 10 (range = 3–72) for hand washing with standing water, and 10 ± 12 (range = 0–79) for washing with running tap water. The results of this study show the possibility of finding fibres on the hands of a person involved in a criminal case even after hand washing before fibre collection.  相似文献   

10.
《Science & justice》2014,54(2):141-145
The implications of the recent recommendations of the Law Commission regarding the use of admissibility tests have the potential to be far reaching for forensic disciplines that rely on the expertise of highly qualified expert witnesses. These disciplines will need a concomitant body of peer-reviewed experiments that provides a basis for the interpretations of such evidence presented in court. This paper therefore, presents such results from two experiments which were undertaken to address specific issues that were raised in cases presented in the British courtroom. These studies demonstrate that there is a variability in the persistence of Lily, Daffodil and Tulip pollen when exposed to high temperatures between 0.5 min and 1440 min (24 h). It was possible to identify all three pollen types after 30 min of exposure to 400 °C, and after shorter time frames the threshold for successful identification was 700 °C after 0.5 min for all pollen types tested and 500 °C for Daffodil and Lily after 5 min of heat exposure. Over longer time periods (18 h (1080 min)) the different pollen types were found to persist in a viable form for identification at 300 °C (Lily), 200 °C (Daffodil) and 50 °C (Tulip). These findings, albeit from a small sample of pollen types, provide empirical contextual information that would contribute to such evidence having sufficient scientific weight to meet admissibility criteria and be viable evidence for a court. These studies demonstrate the value in seeking pollen evidence from even such extreme crime scenes as encountered in vehicular fires.  相似文献   

11.
IntroductionIn this paper, the authors presented a case of acrylamide poisoning in a middle-aged woman who had underwent unsuccessful cosmetic surgery six years earlier. The victim was told that the product that had been injected into her face was Restylane®, which mainly contained sodium hyaluronate and was the first and only Food and Drug Administration (FDA)-approved dermal filler for lip enhancement in the USA for more than 20 years. Widespread facial infections occurred several years post-injection; finally, the victim had to undergo removal surgery. Acrylamide poisoning was strongly suspected based on the victim's clinical manifestation. The product that had been injected into the victim's face was probably polyacrylamide hydrogel-based product, which had been prohibited by the State Food and Drug Administration (SFDA) in China in 2006. To confirm this suspicion, a systematical method was established to differentiate varieties of cosmetic surgery products and identify residential acrylamide.MethodsThe removed objects, original products and a certified reference sample of Restylane® were collected for examination. A direct microscopic examination was applied as a rapid screening method. Fourier transform infrared (FTIR) microspectroscopy analysis was subsequently performed to distinguish the main components from each sample. Automated solid phase extraction, ultra high performance liquid chromatography (SPE UHPLC) analysis was ultimately utilised and optimised to detect the residual acrylamide. Chromatographic separation was achieved on an ACQUITY UHPLC HSS T3 column. The mobile phase consisted of 0.01% aqueous formic acid solution and acetonitrile. The tunable UV (TUV) detection wavelength was at 202 nm.ResultsThe microscopic examination indicated that different samples had different morphological characteristics, depending on their main components. The FTIR spectrum showed that different polymers could be distinguished according to the CO stretching vibration (1655 cm? 1), NH bending vibration (1540 cm? 1) and CO stretching vibration (1078 and 1045 cm? 1). The UHPLC results demonstrated that the calibration curve was linear in the range of 0.5–20.0 μg/mL, with a correlation coefficient of 0.999. The average recoveries of the method were 99–107% with an RSD of 1.6–6.3%. The detection limit was 0.1 μg/mL (S/N = 3). The analytical time was 6 min per sample. Acrylamide was detected in the allegedly Restylane® injection.ConclusionsThis systematical method provides a rapid, accurate and sensitive determination of polyacrylamide and residual acrylamide. The microscopic and FTIR spectroscopic examinations help to verify the existence of polyacrylamide quickly and easily. The optimised SPE UHPLC-TUV method offers a simpler and more sensitive approach to confirm the amount of acrylamide, comparing to the methods in the literature.  相似文献   

12.
PurposeTo construct an empirically rigorous typology of multiple homicide offenders (MHOs).MethodThe current study conducted latent class analysis of the official records of 160 MHOs sampled from eight states to evaluate their criminal careers.ResultsA 3-class solution best fit the data (?2LL = ?1123.61, Bayesian Information Criterion (BIC) = 2648.15, df = 81, L2 = 1179.77). Class 1 (n = 64, class assignment probability = .999) was the low-offending group marked by little criminal record and delayed arrest onset. Class 2 (n = 51, class assignment probability = .957) was the severe group that represents the most violent and habitual criminals. Class 3 (n = 45, class assignment probability = .959) was the moderate group whose offending careers were similar to Class 2.ConclusionA sustained criminal career with involvement in versatile forms of crime was observed for two of three classes of MHOs. Linkages to extant typologies and recommendations for additional research that incorporates clinical constructs are proffered.  相似文献   

13.
A novel application of visible wavelength hyperspectral image analysis has been applied to determine the age of blood stains up to 30 days old. Reflectance spectra from selected locations within the hyperspectral image, obtained from a portable instrument, were subjected to spectral pre-processing. This was followed by the application of a linear discriminant classification model, making estimations possible with an average error of ± 0.27 days for the first 7 days and an overall average error of ± 1.17 days up to 30 days. This is also the first reported study of the determination of the age of fresh blood stains (less than one day old) with an error of ± 0.09 h. The studies have been made under controlled conditions and represent, at this stage, proof of concept results but also are the most accurate age estimation results for measurements between 0 and 30 days reported to date. The results are consistent with well-established kinetic processes suggesting that the pre-processing stages described are revealing spectroscopic changes which are reliably following the time dependent oxidation of HbO2. The potential for parameterisation of environmental factors to make the method generally applicable at crime scenes is discussed, along with the developments required to further improve classification and to make the instrument genuinely portable.  相似文献   

14.
A gas chromatography–mass spectrometry (GC–MS) method was developed and validated for the simultaneous qualification and quantification of methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-amphetamine (MDA), ketamine (KET) and norketamine (NKT) in fingernails. Fingernail samples (20 mg) were washed with distilled water and methanol, digested with 1.0 M sodium hydroxide at 95 °C for 30 min, and then extracted with ethyl acetate. Extract solutions were evaporated to dryness, derivatized using heptafluorobutyric anhydride (HFBA) at 60 °C for 30 min, and analyzed by GC–MS. The linear ranges were 0.1–20.0 ng/mg for AP, MDMA and NKT, 0.2–20.0 ng/mg for MA and MDA, and 0.4–20.0 ng/mg for KET, with the coefficients of determination (r2  0.9989). The intra- and inter-day precisions were within 7.1% and 10.6%, respectively. The intra- and inter-day accuracies were ?10.9% to 0.8% and ?4.3% to 4.5%, respectively. The limits of detections (LODs) and the limits of quantifications (LOQs) for each analyte were lower than 0.094 ng/mg and 0.314 ng/mg, respectively. The recoveries were in the range of 72.3–94.9%. The average fingernail growth rates of two subjects for three years and six subjects for two months were 3.12 mm/month and 3.16 mm/month, respectively. The method proved to be suitable also for the simultaneous detection and quantification of MA, MDMA, KET and their metabolites in fingernails.  相似文献   

15.
A search area of a crime scene to recover trans-dermal artefacts (here, earrings) was conducted using 12 pig carcasses, of various sizes, with pierced ears; 6 were buried and 6 deposited on the surface in a wooded area. After 28 months, the remains were excavated and recovered, and the final location of the earrings recorded. The furthest recorded earring from its associated surface remains was 119 cm. In the buried remains, on three occasions earrings were found located 6 cm below the recorded base of the grave. Formal recommendations for the search area of a crime scene have been established as 120 cm radius from the originally located remains, whether surface deposition or burial, and confirmation of excavation below the assumed floor of the grave in burials is essential, at least to 10 cm.  相似文献   

16.
In post-mortem work, blood is a potential source of external contamination of hair. The present study was carried out to investigate the amount of drug absorbed into hair which has been contaminated with blood containing either cocaine or BE. Solutions were prepared containing 0.05, 0.1, 0.2, 0.5 and 3.0 μg/mL of either cocaine or BE in human blood. Samples of approximately 3.2 g of drug-free hair were contaminated by soaking in the blood solutions for 5 min. They were then removed and left at room temperature. Approximately 0.5 g of hair was collected from each of the blood soaked hair samples at 6 h, 1, 2, 4 and 7 days after contamination. As each hair sample was collected it was shampoo-washed to prevent further drug absorption. Hair samples were analysed in triplicate using a fully validated method described previously. EME and cocaethylene were also measured in order to find out if cocaine or BE was breaking down to these compounds. Both cocaine and BE were absorbed into hair in significant concentrations when the concentration in the blood was 0.5 μg/mL or greater; cocaine was more readily absorbed than BE. Cocaine broke down to EME (<LOQ) at 0.5 μg/mL and to EME (>LOQ) and BE (<LOQ) at 3.0 μg/mL. When the blood concentration of cocaine was 0.5 μg/mL or less, there was no evidence of it breaking down to form BE. From the samples soaked in blood containing BE, there was no evidence of the BE breaking down. The absorption of drug into hair did not increase as the contamination period increased from 6 h to 7 days.  相似文献   

17.
The study of decaying organisms and death assemblages is referred to as forensic taphonomy, or more simply the study of graves. This field is dominated by the fields of entomology, anthropology and archaeology. Forensic taphonomy also includes the study of the ecology and chemistry of the burial environment. Studies in forensic taphonomy often require the use of analogues for human cadavers or their component parts. These might include animal cadavers or skeletal muscle tissue. However, sufficient supplies of cadavers or analogues may require periodic freezing of test material prior to experimental inhumation in the soil. This study was carried out to ascertain the effect of freezing on skeletal muscle tissue prior to inhumation and decomposition in a soil environment under controlled laboratory conditions. Changes in soil chemistry were also measured. In order to test the impact of freezing, skeletal muscle tissue (Sus scrofa) was frozen (?20 °C) or refrigerated (4 °C). Portions of skeletal muscle tissue (~1.5 g) were interred in microcosms (72 mm diameter × 120 mm height) containing sieved (2 mm) soil (sand) adjusted to 50% water holding capacity. The experiment had three treatments: control with no skeletal muscle tissue, microcosms containing frozen skeletal muscle tissue and those containing refrigerated tissue. The microcosms were destructively harvested at sequential periods of 2, 4, 6, 8, 12, 16, 23, 30 and 37 days after interment of skeletal muscle tissue. These harvests were replicated 6 times for each treatment. Microbial activity (carbon dioxide respiration) was monitored throughout the experiment. At harvest the skeletal muscle tissue was removed and the detritosphere soil was sampled for chemical analysis. Freezing was found to have no significant impact on decomposition or soil chemistry compared to unfrozen samples in the current study using skeletal muscle tissue. However, the interment of skeletal muscle tissue had a significant impact on the microbial activity (carbon dioxide respiration) and chemistry of the surrounding soil including: pH, electroconductivity, ammonium, nitrate, phosphate and potassium. This is the first laboratory controlled study to measure changes in inorganic chemistry in soil associated with the decomposition of skeletal muscle tissue in combination with microbial activity.  相似文献   

18.
《Science & justice》2020,60(6):538-546
The chemical profiling of bloodstains is essential to link the suspect with the crime. The current study proposed a proof-of-concept methodology for the investigation of bloodstains by utilizing advanced ATR-FTIR spectroscopy coupled with new generation chemometric methods. Current study provides encouraging data to allow discrimination between human and animal blood though with small sample size. In this study, different models for the age estimation of human bloodstains are developed from the trained data sets of 1–175 days old bloodstains. The models such as curve estimation (CE), multiple linear regression (MLR), and partial least squares regressions (PLSR) are developed to determine the best prediction model for aged human bloodstains. The obtained results on the dating of bloodstains are very encouraging and also tested for unknown samples. The maximum dating errors are observed in the curve estimation models whereas, the other models MLR, PLSR show excellent age estimation of unknown bloodstains. These models represent an error of ~3 ± 1 days and ~4 ± 1 days in actual and estimated date, respectively, which is lowest ever reported so far. The present methodology is expected to provide a valuable insight into forensic society and hence, to the law enforcement community. The present methodology can further be explored for an ideal model by including all other external variables/factors and for more longer aging time.  相似文献   

19.
Many scientists of varying clinical backgrounds have described the phenomenon of spermaturia in animals, adolescents as well as fertile and infertile men. Nevertheless, research for an expert opinion on a law case in the field of forensic medicine revealed a lack of valid information about the longevity of spermatozoa in post-ejaculatory urine (PEU) of fertile men.Our goal was to measure the appearance of vivid sperm in PEU while considering the factor of time in order to predict a realistic interval, in which positive sperm findings might occur. Therefore ten healthy, young men donated their sperm for fertility analysis and a urine sample prior to and after ejaculation. The time intervals between ejaculation and the first micturition were preset ranging between 30 min and maximal 11 h. Each ejaculate underwent a semen analysis. The pre- and post-ejaculatory urine samples were screened for the presence of viable and motile spermatozoa. Semen parameters were determined and related to the sperm findings in the precipitate of the urine samples. The amount, the viability and motility status of the detected spermatozoa were recorded after each preset time interval.The results showed that none of the 10 participants had sperm in their urine samples prior to ejaculation. The average sperm concentration was 50.1 ± 25.8 million/ml. After a time span of 30 min 59.5% of the first fractions of PEU samples were sperm positive, after 2 and 4 h still 70%, and after 5 h sperm were no longer detected. The last motile spermatozoa could be found after 4.5 h. It seems that remaining sperm in the urethra are washed out with the first micturition in the majority of fertile men, however, the conclusion as to whether sperm findings >5 h after ejaculation are improbable needs to be confirmed by further investigations.  相似文献   

20.
The Indian wild pig (Sus scrofa cristatus) is a protected species and listed in the Indian Wildlife (Protection) Act, 1972. The wild pig is often hunted illegally and sold in market as meat warranting punishment under law. To avoid confusion in identification of these two subspecies during wildlife forensic examinations, we describe genetic differentiation of Indian wild and domestic pigs using a molecular technique. Analysis of sequence generated from the partial fragment (421 bp) of mitochondrial DNA (mtDNA) cytochrome b (Cyt b) gene exhibited unambiguous (> 3%) genetic variation between Indian wild and domestic pigs. We observed nine forensically informative nucleotide sequence (FINS) variations between Indian wild and domestic pigs. The overall genetic variation described in this study is helpful in forensic identification of the biological samples of wild and domestic pigs. It also helped in differentiating the Indian wild pig from other wild pig races. This study indicates that domestic pigs in India are not descendent of the Indian wild pig, however; they are closer to the other wild pig races found in Asia and Europe.  相似文献   

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