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1.
裂解气相色谱法检验静电复印墨粉   总被引:2,自引:1,他引:1  
静电复印墨粉是复印文件检验的重要组成部分。本文通过电熨斗加热提取纸张上的墨粉,排除了纸张的平扰,用裂解气相色谱法对9个厂家共23个型号的墨粉进行检验。研究表明。该方法灵敏度高,分辨能力强,区分率可达到90.3%,是一种有效的检验方法。  相似文献   

2.
Automobile tire marks can routinely be found at the scenes of crime, particularly hit-and-run accidents and are left on road surfaces because of sudden braking or the wheels spinning. The tire marks are left due to the friction between the tire rubber and the solid road surface, and do not always demonstrate the tire tread pattern. However, the tire mark will contain traces of the tire. In this study, Pyrolysis Gas Chromatography/Mass Spectrometry was used to analyze 12 tires from different manufacturer's and their traces collected after braking incidents. Tire marks were left on a conglomerate road surface with sudden braking. The samples were pyrolysed without removal of contaminant in a micro-furnace type pyrolyser. Quantitative and qualitative analysis were performed on all the samples. All 12 samples were distinguished from each other. Each of the tire traces were identified as coming from there original source.  相似文献   

3.
The detection of DNA is inhibited in cases of sexual assault involving condom use. Trace evidence, including condom lubricant residues, provides crucial associative evidence in such cases. The existing Fourier transform infrared spectroscopy (FTIR) methods for lubricant analysis and detection are limited with regard to sensitivity and discrimination. The aim of this research was to establish a new method as an alternative to FTIR for the analysis of condom lubricant residues. Pyrolysis gas chromatography-mass spectrometry (PyGC-MS) and GC-MS are highly sensitive methods of analysis for a wide range of chemical substances. PyGC-MS and GC-MS were used to analyze condom lubricants in standard solution, from clean swabs and from postcoital swabs. Pyrolysis of polydimethylsiloxane (PDMS) lubricant forms cyclic products known as cyclic dimethyl siloxanes (DMS), which are separated and detected by the GC-MS. The polyethylene glycol (PEG) lubricant can be analyzed by GC-MS directly from solution. The methods of extraction and analysis presented in this paper were shown to be significantly more sensitive than FTIR for the analysis of PDMS and PEG condom lubricants. PDMS was detected as low as 1 mug in standard solution and from clean swabs using the PyGC-MS method. PEG was detected as low as 0.5 microg from standard solution and 50 mug from clean swabs using the GC-MS method. Unfortunately, we were unable to provide further discrimination between condom brands and subbrands. The methods established throughout the research were used successfully to detect condom lubricants from donated postcoital swabs. Lubricants were detected in abundance on swabs 12 h postcoitus. Recommendations are made regarding implementation of new methods for routine analysis of casework samples along with strict pyrolysis interpretation criteria to minimize the possibility of misinterpretation of false positives.  相似文献   

4.
A sensitive radioimmunoassay for paraquat is reported. Anti-paraquat antisera were produced by repeated immunization in rabbits with 1-methyl, 1'-hexanoic acid-4,4'-bipyridinium (MHBP) coupled to bovine serum albumin (BSA). Less than 0.5 ng of paraquat dichloride was detectable by this assay system. These antisera were strongly cross-reactive with the bipyridyl ring and methyl group in either the 1- or 1'-position of paraquat. The determination of paraquat in tissues of paraquat-poisoned cadavers was also carried out.  相似文献   

5.
In a given case with two or more siblings the bloodgroup findings may yield a high plausibility of paternity for the alleged father of the children whilst the HLA-A,B characteristics may exhibit an exclusion of fatherhood of one or other of the siblings. But this "exclusion" may disappear assuming an HLA-A,B recombination of a father's (or mother's) gamete. In such cases simple calculations (i.e., by hand) can provide the serostatistical characteristic L = Y/X (after Essen-M?ller) for the given HLA-A,B constellation. In two-child cases with HLA-A,B findings for the putative father, the two pedigrees for the counterhypothesis Y are Yg1 and Yg2. The one holds for the case where the putative father is the father of child 1 and the other for the case where he is the father of child 2; in each case an unknown man is the father of the other child. The likelihood ratio is calculated as follows: L = Y/X = 1/r.p(3,3).p(3,4).[p(4,4) + p(4,3)]/[p(3,3).p(4,4) + p(3,4).p(4,3)], where p(3,3) and p(4,4) are the frequencies of the putative father's HLA-A,B haplotypes in the pedigree YH1, p(3,4) and p(4,3) those in pedigree YH2, and where r is the recombination rate. In three-child cases and others in which the putative father is deceased and HLA results from legitimate children or siblings are available, and in which fatherhood is only possible if a recombinant haplotype interferes, only one counter-hypothesis exists. In these cases, the likelihood ratio is represented by L = Y/X = 2/r.p(HR).2I, where p(HR) means the frequency of the recombinant HLA-A,B haplotype, r the recombination rate and I(0, 1 or 2) the "difference in determined types."  相似文献   

6.
目的建立分泌抗三唑仑代谢物α-羟基三唑仑单克隆抗体的杂交瘤细胞株,制备高特异性的三唑仑代谢物单克隆抗体,为三唑仑及其代谢物免疫分析方法的开发奠定基础。方法在三唑仑分子的6位苯环对位上引入活性氨基基团,然后通过缩合反应分别与匙孔血蓝蛋白(KLH)和牛血清白蛋白(BSA)相偶联形成完全抗原。以三唑仑-KLH免疫Balb/c小鼠,通过细胞融合,筛选等杂交瘤技术建立稳定的分泌特异性单克隆抗体的杂交瘤细胞株。纯化后的单克隆抗体,分别用SDS-PAGE电泳法、间接ELISA法和胶体金免疫层析法对其纯度、效价及灵敏度和特异性进行测定。结果获得3株能稳定分泌三唑仑代谢物单克隆抗体的杂交瘤细胞株,分别命名为2G4,4B2和5H6。2G4和4B2抗体只与三唑仑代谢物α-羟基三唑仑有反应,灵敏度分别为500ng/mL和750ng/mL。与其他参试物无交叉反应。因5H6抗体为IgM,考虑到纯化难度和实际应用的限制,暂未做深入研究。结论本研究制备的2G4和4B2单克隆抗体仅识别三唑仑代谢物α-羟基三唑仑,具有高度特异性和灵敏度。  相似文献   

7.
Implementation of massively parallel sequencing platforms can bring a great contribution to Forensic Genetics field, with a great saving of time and costs, as well as allowing reliable results to be obtained from small or extremely degraded samples. The aim of this work was to analyze 124 SNP loci (90 autosomal and 34 Y-SNP) included in HID-Ion Ampliseq Identity Panel in a small sample from Rio de Janeiro state, Brazil. Samples from 12 non-related individuals were amplified with HID-Ion Ampliseq Identity Panel and sequenced on the Ion Torrent PGM platform (Thermo Fisher Scientific); genotypes were generated with HID SNP Genotyper plugin and forensic parameters were calculated with PowerStats v.12. All samples were successfully genotyped and were used to calculate allele frequencies, homozygosity, heterozygosity, random match probability (RMP) and exclusion power for all 90 autosomal SNP loci. Using the formula proposed by Budowle et al. (1996), only 4 of the 90 loci genotyped (4,4%) showed allele frequencies below the minimum required. It means that although a small set of individuals was used on this study, it may have shown a good perspective of Rio de Janeiro state allele frequencies. Among the 11 male samples analyzed, a prevalence of the haplogroup R1b of Y chromosome was observed, followed by the haplogroups E, Q and J. Such distribution reflects the results demonstrated in other studies for the population of Rio de Janeiro. All results together demonstrate the usefulness and applicability of SNP analysis on Ion Torrent PGM.  相似文献   

8.
王韬 《河北法学》2012,(1):177-178,179,180,181,182
告诉乃论制度对充分保障被害人权利、实现刑罚谦抑、促进刑事和解具有重要意义。大陆法系各国均规定了数量庞大的亲告罪,我国的亲告罪名却很少,类型也很单一。制约亲告罪范围扩大的真正原因在于我国亲告罪告诉机制的缺陷。我国刑法与刑事诉讼法对亲告罪告诉权的救济性规则缺乏,亲告罪与自诉罪混淆,告诉权与证明责任混淆,告诉制度不完善。通过归纳、比较各国刑事立法例中的优劣,认为我国可采被害人可自由选择自诉的混合起诉制,以弥补亲告罪告诉机制的缺陷。  相似文献   

9.
Age at death estimation in adult skeletons is hampered, among others, by the unremarkable correlation of bone estimators with chronological age, implementation of inappropriate statistical techniques, observer error, and skeletal incompleteness or destruction. Therefore, it is beneficial to consider alternative methods to assess age at death in adult skeletons. The decrease in bone mineral density with age was explored to generate a method to assess age at death in human remains. A connectionist computational approach, artificial neural networks, was employed to model femur densitometry data gathered in 100 female individuals from the Coimbra Identified Skeletal Collection. Bone mineral density declines consistently with age and the method performs appropriately, with mean absolute differences between known and predicted age ranging from 9.19 to 13.49 years. The proposed method—DXAGE—was implemented online to streamline age estimation. This preliminary study highlights the value of densitometry to assess age at death in human remains.  相似文献   

10.
The aim of this study is to investigate the mechanism of injury of abducens nerve at petroclival region in severe head trauma. Twenty specimens provided from 10 autopsied cases due to severe head trauma were investigated macroscopically and histopathogically. The slices of the abducens nerve taken consecutively along its course at petroclival region were stained with Hematoxylline-Eosin and evaluated under light microscope. In addition, coexisting cervical injuries in these cases were assessed macroscopically. Edema and perineural hemorrhagia of abducens nerve were identified in all cases. Nerve injury was found more exaggerated at the sites of dural entry point and petrous apex than any other parts of the abducens nerve. Furthermore, microscopically, also remarkable perineural hemorrhage of the abducens nerve was observed at the site of its anastomoses with the sympathetic plexus on the lateral wall of the internal carotid artery (ICA). Abducens nerve is injured at the sites of dural entry point, petrous apex and lateral wall of the ICA, directly proportional with the severity of the trauma. This finding is also significant in verification of the severe head trauma.  相似文献   

11.
Objective measurements were carried out to study the evolution of rigor mortis on rats at various temperatures.Our experiments showed that:(1) at 6 °C rigor mortis reaches full development between 48 and 60 hours post mortem, and is resolved at 168 hours post mortem; (2) at 24 °C rigor mortis reaches full development at 5 hours post mortem, and is resolved at 16 hours post mortem; (3) at 37 °C rigor mortis reaches full development at 3 hours post mortem, and is resolved at 6 hours post mortem; (4) the intensity of rigor mortis grows with increase in temperature (difference between values obtained at 24 °C and 37 °C); and (5) at 6 °C a “cold rigidity” was found, in addition to and independent of rigor mortis.  相似文献   

12.
It is a commonplace that 'non-discrimination' is a fundamental principle of Community Law. If the principle is taken to express a broader commitment to equality, however, there appears to be something quite unusual about it. When compared with the standards set by modern constitutional law, the commitment to equality is, at least with respect to Member State action, less extensive; in the context of indirect gender discrimination, however, the principle acquires remarkable scope. Although this 'vanguard moment' of Community Law is tacitly acknowledged in the practice of the ECJ, it is, at the same time, subdued; the resources of the principle might be tapped, however, by moving toward a constitution for antidiscrimination. The article explores both the philosophical presuppositions and the institutional context of what could become a constitutionalisation of antidiscrimination at the level of Community Law.  相似文献   

13.
A large number of alleles from the six different short tandem repeat (STR) loci FGA, D3S1358, vWA, CSF1PO, TPOX and TH01, used in human identity testing were sequenced to provide support for the robustness of fluorescent STR DNA typing by allele size. Sequence information for some of these loci (FGA, vWA, TH01) is an extension of published work, whereas no extensive sequence information is available with respect to the D3S1358, CSF1PO, and TPOX loci. Sequencing of alleles at each locus has provided quantitative data with respect to the true nucleotide length of common alleles, and of alleles that vary in length from the common alleles. All alleles that were identified as "off-ladder" alleles through fluorescent typing at these STR loci have proven to be true length variant alleles. Sequencing at the D3S1358 and CSF1PO loci allowed for the establishment of a common nomenclature for these loci. A correlation between percent stutter and the length of the core tandem repeat is demonstrated at the FGA locus. Alleles in which the core tandem repeat is interrupted by a repeat unit of different sequence have a reduced percent stutter. DNA samples from three non-human primates (chimpanzee, orangutan, and gorilla) were compared to the human sequences, and shown to differ markedly across loci with respect to their homology. The effects of primer binding site mutations on the amplification efficiency at a particular locus, and methods used to interpret amplification imbalance of heterozygous alleles at a locus is also addressed.  相似文献   

14.
The combination of photographs taken at wavelengths at and bracketing the peak of a narrow absorbance band can lead to enhanced visualization of the substance causing the narrow absorbance band. This concept can be used to detect putative bloodstains by division of a linear photographic image taken at or near 415 nm with an image obtained by averaging linear photographs taken at or near 395 and 435 nm. Nonlinear images can also be background corrected by substituting subtraction for the division. This paper details experimental applications and limitations of this technique, including wavelength selection of the illuminant and at the camera. Characterization of a digital camera to be used in such a study is also detailed. Detection limits for blood using the three wavelength correction method under optimum conditions have been determined to be as low as 1 in 900 dilution, although on strongly patterned substrates blood diluted more than twenty-fold is difficult to detect. Use of only the 435 nm photograph to estimate the background in the 415 nm image lead to a twofold improvement in detection limit on unpatterned substrates compared with the three wavelength method with the particular camera and lighting system used, but it gave poorer background correction on patterned substrates.  相似文献   

15.
随着上海经济的高速发展 ,交通口岸的治安状况发生了很大的变化 ,机场治安日益复杂 ,码头治安渐趋平稳 ;长途汽车站治安问题突出 ;火车站社区化 ,流窜犯罪辐射面扩大 ;公路道口打流截逃任务加剧。为此 ,必须建立一套适应新形势发展需要的完善的“口岸”打流机制。  相似文献   

16.
The combination of photographs taken at two or three wavelengths at and bracketing an absorbance peak indicative of a particular compound can lead to an image with enhanced visualization of the compound. This procedure works best for compounds with absorbance bands that are narrow compared with "average" chromophores. If necessary, the photographs can be taken with different exposure times to ensure that sufficient light from the substrate is detected at all three wavelengths. The combination of images is readily performed if the images are obtained with a digital camera and are then processed using an image processing program. Best results are obtained if linear images at the peak maximum, at a slightly shorter wavelength, and at a slightly longer wavelength are used. However, acceptable results can also be obtained under many conditions if non-linear photographs are used or if only two wavelengths (one of which is at the peak maximum) are combined. These latter conditions are more achievable by many "mid-range" digital cameras. Wavelength selection can either be by controlling the illumination (e.g., by using an alternate light source) or by use of narrow bandpass filters. The technique is illustrated using blood as the target analyte, using bands of light centered at 395, 415, and 435 nm. The extension of the method to detection of blood by fluorescence quenching is also described.  相似文献   

17.
《Russian Politics and Law》2013,51(2):101-107
The monograph under review is devoted essentially to general questions of the systems approach and systems methodology and to their interpretation with respect to the field of state administration. In this area the authors have arrived at some new findings of scholarly and practical interest. But the main feature of the book is its bringing the general principles of the systems approach to a level of concreteness at which its effective application at the level of a branch of state administration is possible. There are as yet few similar studies in Soviet legal literature.  相似文献   

18.
This study examined the in vitro stability of 6-acetylmorphine (6AM) in horse blood, sheep vitreous humour (VH) and homogenised deer muscle stored under different storage conditions. The stability of 6AM in horse blood is of interest because many toxicological laboratories utilise this matrix for the preparation of blood calibration and check standards and the latter are typically stored during routine use. Data on the storage stability of 6AM in human VH is extremely limited and no data has been reported in muscle. In the absence of human samples, 6AM stability was demonstrated in sheep vitreous and deer muscle. Blood and VH were stored with and without NaF at room temperature (RT), 4 and -18°C for 84 days. Muscle tissue homogenates were prepared in water with and without NaF and also in phosphate buffer (pH 6.0) containing NaF. Homogenates were stored for 31 days at RT, 4 and -18°C. Morphine and 6AM were extracted using SPE and quantified by GC-ion trap-MS/MS. In the absence of NaF, 6AM could not be detected after 7 and 14 days in blood stored at RT and 4°C, respectively. Although at -18°C 6AM was stable for 7 days (12% loss), only 54% was detected by day 84. The addition of NaF to horse blood increased 6AM stability substantially at every temperature. Further, the rate of degradation was found to be significantly slower in blood preserved with 2% NaF compared with 1% NaF (p=.05). 6AM was stable for the study period in preserved blood (1 and 2% NaF) stored at -18°C. For laboratories utilising horse blood in the preparation of standards, preservation with 1% NaF (minimum) and storage at -18°C is recommended. The addition of NaF to VH was essential for 6AM stability. Irrespective of temperature substantial losses (≥ 42%) were observed in unpreserved sheep VH by day 7. In preserved VH the concentration declined by only 22% on day 7 following storage at RT and no loss observed in VH stored at 4 and -18°C at the same time. In muscle, 6AM was stable for 7 days in preserved samples stored at RT and in all samples stored at 4°C and below. The addition of NaF increased the stability of 6AM substantially in muscle. The increased stability of 6AM in VH and muscle preserved with fluoride was attributed to inhibition of bacterial action and the subsequent reduction in the rate of putrefaction of these tissues.  相似文献   

19.
This is the text of a lecture delivered at the World Conference of the International Academy of Law and Mental Health in Sydney in September 2003 on the occasion of the award to the author of the Prix Philippe Pinel. Its theme is the potential of the European Convention on Human Rights to secure the human rights of people with mental disorders and disabilities, viewed in the context of the legislation on mental health and mental incapacity in England and Wales. Its conclusion is that the Convention is better at protecting them from unwanted or unnecessary treatment and care than it is at securing for them equal access to the treatment and care they want or need. The lecture has been updated to reflect developments in the United Kingdom since 2003.  相似文献   

20.
家兔死后离体血液ATP含量变化与放置时间的关系   总被引:1,自引:1,他引:0  
目的探讨恒温(25℃)条件下家兔死后离体血液ATP含量变化与放置时间的关系。方法健康家兔8只,空气栓塞处死后即刻取右心室血液,置于25℃恒温水浴槽中,每4h应用ATP荧光快速检测仪检测血液ATP含量,所得数据应用SPSS17.0统计学软件进行方差检验及回归分析。结果恒温(25℃)环境下,家兔死后离体血液的ATP含量,在8h内从死后即刻的2.46×10-12mol/L升至3.09×10-12mol/L,8h之后则随PMI的延长而下降,直至56h,56~72h ATP含量在0.13×10-12mol/L时趋于稳定。以Log[ATP]为因变量(y),离体放置时间为自变量(x),对死后0~56h的数据进行回归曲线分析,建立了3个推断离体时间方程,即y=-0.019x-11.359(R2=0.763)、y=0.001x2+0.016x-11.666(R2=0.962)和y=-1.281×10-5x3-0.007x-11.576(R2=0.980),其中三元回归方程的系数为0.980,曲线拟合度最好。结论家兔离体血液ATP含量变化与放置时间呈现一定的规律性,有望应用于死亡时间推断。  相似文献   

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