傅里叶显微红外光谱成像技术研究进展及其法医学应用

傅里叶显微红外光谱成像技术可收集微小物体的红外光谱信息,针对组织切片和细胞进行扫描,记录选择区域像素位点的红外光谱信息,并通过计算机软件构建出组织和细胞中光谱吸收峰的二维和三维光谱映射图像.由于红外光谱对生物大分子的敏感性,通过该技术可以有效分析组织和细胞的生化构成、分子分布、代谢变化.本文阐述了傅里叶显微红外光谱成像...     

On the frequency of occurrence of a peculiar polyester fibre type found in blue denim textiles

In a double murder investigation, the victims were found after a prolonged stay in a drainage canal. In spite of the expectations, fibre examination established a multitude of primary and secondary transferred fibres. One of these fibre types was a colourless polyester fibre possessing a blue coloured molten fibre end. These matched one of the types present in the suspect's blue denim trousers. The aim of this study was to verify the rarity of this peculiar fibre type and more precisely its presence in blue denim textiles. Over five hundred different blue jeans textiles were examined and only one of these presented exactly the same type. The comparison involved microscopy, microspectrophotometry in the visible range and Raman spectroscopy. The results indicate this fibre type is extremely rare in a blue jeans fabrics and that “standard” blue denim should not be disregarded in case work.     

Detection of latent bloodstains beneath painted surfaces using reflected infrared photography

Bloodstain evidence is a highly valued form of physical evidence commonly found at scenes involving violent crimes. However, painting over bloodstains will often conceal this type of evidence. There is limited research in the scientific literature that describes methods of detecting painted-over bloodstains. This project employed a modified digital single-lens reflex camera to investigate the effectiveness of infrared (IR) photography in detecting latent bloodstain evidence beneath a layer or multiple layers of paint. A qualitative evaluation was completed by comparing images taken of a series of samples using both IR and standard (visible light) photography. Further quantitative image analysis was used to verify the findings. Results from this project indicate that bloodstain evidence can be detected beneath up to six layers of paint using reflected IR; however, the results vary depending on the characteristics of the paint. This technique provides crime scene specialists with a new field method to assist in locating, visualizing, and documenting painted-over bloodstain evidence.     

实验性大鼠弥漫性轴索损伤的傅里叶红外光谱检测

目的探讨利用傅里叶红外光谱技术诊断弥漫性轴索损伤的可行性。方法利用HE染色、银染和β-APP免疫组化染色确认大鼠弥漫性轴索损伤模型,利用傅里叶变换显微红外光谱面扫描成像技术检测弥漫性轴索损伤区域酰胺Ⅱ带的光谱分布情况,得到弥漫性轴索损伤的红外光谱数据,绘制红外光谱病理图像。结果实验组与对照组的酰胺Ⅱ带红外光谱吸收度之间存在明显差异,红外光谱病理图像中酰胺Ⅱ带的高吸收区与弥漫性轴索损伤区符合。结论傅里叶红外光谱技术可对弥漫性轴索损伤进行病理形态学诊断。     

Analysis of carbohydrates in seized heroin using capillary electrophoresis

Illicitly produced heroin is commonly cut with carbohydrates to increase bulk. The analysis of these solutes is important for legal and intelligence purposes. A capillary electrophoresis (CE) method was developed for the qualitative analysis of dextrose, lactose, sucrose, inositol, and mannitol in heroin exhibits. For this method, a 64 cm (55.5 cm to detector window) by 50 mum capillary was used with the Agilent Basic Anion Buffer modified to pH 12.1. This separation was performed at 25 degrees C with a voltage of 20 kV and indirect detection with 2,6-pyridinedicarboxylic acid as the visualization reagent. The methodology is also applicable for the screening of inorganic and organic anions using indirect detection, and acidic adulterants using direct detection. For a run time of 13 min, the relative standard deviation (n = 6) of the methodology was better than 0.36% for migration times and less than 2.6% for corrected peak areas. For the analysis of carbohydrates and acidic adulterants in seized heroin, excellent agreement was obtained between CE and nuclear magnetic resonance spectroscopy.     

浅论我国社会转型时期思想领域的集体越轨

社会转型时期,人们思想观念和行为习惯上出现的失范和紊乱、封建迷信思想的侵袭、病态社会心理等导致了思想领域集体越轨行为的产生。反叛性的集体越轨是一个不可忽视的社会不安定因素,必须加强社会控制,把集体越轨的危害降到最低,使社会健康、有序地发展。     

西部开发与彝族传统文化的传承、发展研究

文章论述了彝族在历史发展过程中创造了丰富的民族传统文化,彝族传统文化是我国民族文化的重要组成部分。西部开发,给民族文化的传承带来了机遇和挑战,应该正确认识挑战,抓住机遇,很好地传承和创新民族传统文化。     

政府职能转变平台的建设与创新

政府职能的转变对政府的自身建设和管理创新提出了新的要求。在新形势下,建设政府政务大厅是推行阳光政务、预防腐败和建设和谐社会的重要举措。山东省莒南县政务大厅的建设、运行及其成效充分证明了其重要性和可行性。     

Differentiation of Commercially Available Kratom by Purported Country of Origin using Inductively Coupled Plasma–Mass Spectrometry,

Kratom is a plant material exhibiting both analgesic and stimulant effects and is also forensically relevant since it is abused as a “legal high.” It is regulated in several countries but not scheduled in the United States at the federal level. This study used inductively coupled plasma–mass spectrometry (ICP–MS) to measure the concentrations of 13 elements in 19 kratom samples obtained from an online distributor selling kratom, from Borneo, Malaysia, Indonesia, Thailand, and Vietnam, for the purpose of using the elements to discriminate among purported country of origin, “suborigin,” and strain. Analysis of variance revealed statistical differences in concentrations of elements from each group, while discriminant function analysis (using leave-one-out classification) successfully classified kratom samples by their purported country of origin (100%), “suborigin,” (100%), and strain (86%). Our method illustrates the possibility of utilizing ICP–MS for determination of commercially available kratom samples by purported origin, “subororign,” or by product line.     

Toner Particles as Forensic Evidence: Microanalytical Characterization of Known Toner and Recognition of Toner in Environmental Samples*†‡

Modern printing toners represent a prime example of subvisible particles that can be easily transferred to hands, clothing, and other surfaces. To explore the potential evidentiary value of toner particles, toner samples were collected from known printer cartridges and characterized by various microanalytical techniques to establish the properties most useful for recognition, identification, and comparison. Environmental samples (i.e., dust) were then collected from various locations at varying distances from toner-based printers, using both tape lifts and carbon adhesive stubs, to assess the possibility of detecting toner. By light microscopy, toner can be recognized on the basis of particle size and shape, as well as color. Further examination of the micromorphology in the field emission scanning electron microscope reveals characteristic morphologies and differences in surface texture and shape among toner sources. Raman spectroscopy provides chemical identification of the pigment (or pigment class) and, in some cases, also permits identification of the polymer component. While black and blue pigment chemistry remained constant among toner varieties that were studied (copper phthalocyanine and carbon black), variation in yellow and magenta pigments was observed. Analysis of dust samples collected from various environments demonstrated that while toner is consistently detectable in close proximity to printers (within 2 feet), it also can be detected in dust collected in nearby rooms. This research demonstrates that toner particles can be located, characterized, and discriminated, using a suite of microanalytical methods that are applicable to forensic casework.