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11.
Investigating the Potential of Fluorescent Fingerprint Powders as a Marker for Blow Fly Larvae (Diptera: Calliphoridae) 下载免费PDF全文
Jennifer Y. Rosati Ph.D. Scott D. Robinson B.Sc. Richard Devine 《Journal of forensic sciences》2015,60(3):653-658
Four fluorescent fingerprint powders (RedWop?, GreenWop?, Basic Yellow?, and Yellow Powder?) were evaluated as a marker for blow fly larvae. Administration methods included ingestion (high vs. low concentration) or topical. Ingestion of high concentrations of Basic Yellow? and RedWop? caused higher larval mortality. Basic Yellow? delayed development and adult emergence while RedWop? and Yellow Powder? had a significant effect on particular stages of development, however, emergence time was not altered. Optimal administration is through ingestion at low concentration levels (<10%) or topically, with GreenWop? demonstrating minimal adverse effects. Optimum wavelength for discrimination between powders was 450 nm. This research can aid in investigative training to increase visibility of larval and pupal blow flies. It can also be used in entomological studies to differentiate between larval blow flies (or other dipteran) species or individuals to further understand complex interactions and behavior during larval development. 相似文献
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The floral development and potencies [Δ(9) -tetrahydrocannabinol (THC) contents] of cannabis plants were compared when grown indoors under high-pressure sodium lamps consuming electrical power at three densities (270, 400, and 600 W/m(2)). After a 3-week vegetative phase, plants were grown for 8 weeks, with lamps maintaining an artificial day length of 12 h. Foliar and floral yields were measured. Gas chromatography was used to measure the content of the psychoactive cannabinoid THC. Mean yields per unit of electrical power in each lighting regime ranged from 0.9 to 1.6 g/W, the highest being achieved in the lowest irradiance regime. The individual potencies of the separated leaf and flower materials were not affected by increasing irradiance. However, there was a corresponding increase in the overall potency of the aerial plant tissue. This was because of the plants in brighter conditions producing a higher proportion of floral material. 相似文献
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WANG HAI 《今日中国(英文版)》2014,(3):21-21
正ON January 25,Chinese tennis player Li Na polarized the world’s attention when she won the Australian Open,the second Grand Slam championship win of her sports career.Soon,the media was f looded with praise for her performance and the nation’s pride was palpable."Li Na Fever"is set to last. 相似文献
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Xiang Wu Ph.D. Guoliang Ouyang M.Sc. Biao Li M.Sc. Lan Cui M.Sc. Guanglei Zhou M.Sc. 《Journal of forensic sciences》2020,65(4):1242-1246
Determining the application sequence of hand-written pen ink and printer toner lines has attracted significant interest in questioned document examination. This study uses coaxial light to determine line-crossing sequences, with intersections observed under a VSC600 forensic document workstation and a Leica M205A Stereo-microscope. Results show that reflected light at intersections and color contrast between intersections and nonintersections was observed when a hand-written ink line passes over a toner line, while a toner line passing over a written line appeared dull, with no color contrast. The procedure was tested under a range of conditions, such as types of writing pens and laser printers, the writer, and writing pressure, with the latter playing an important role in the evaluation. To validate the results, a 90% detection rate and 98% accuracy rate were achieved from 50 samples of blind testing, which is more effective than optical microscopy. 相似文献
15.
The Effect of Time on Bone Fluorescence: Implications for Using Alternate Light Sources to Search for Skeletal Remains 下载免费PDF全文
Mohamed A. H. Swaraldahab M.S. Angi M. Christensen Ph.D. 《Journal of forensic sciences》2016,61(2):442-444
Bones fluoresce when exposed to certain wavelengths of shortwave light, and this property can be useful in locating and sorting skeletal remains in forensic contexts. The proteins in bone collagen are largely responsible for its fluorescent properties, but these proteins degrade and denature over time. This study examined the fluorescence of bones from four temporal groups (recent, semi‐recent, ancient, and historic) ranging from 0 to 1064 years before present. Specimens were photographed under 490 nm wavelength light, and fluorescence was quantified by converting intensity to a gray scale value based on the RGB color model using ImageJ® software. Significant (p < 0.05) differences were found in mean fluorescence between all four temporal groups, and a 0.324 coefficient of correlation indicates a significant (inverse) relationship between fluorescence and time. Bone fluorescence decreases with time, but some fluorescence is retained even in older samples. Fluorescence can therefore be reliably used in many modern skeletal remains searches. 相似文献
16.
“宽严相济”与“两极化”之辨析 总被引:5,自引:0,他引:5
我国的宽严相济刑事政策与美国的两极化刑事政策在生成背景、基本含义、精神实质等方面都有显著区别,不宜混淆。两极化刑事政策的生成背景是矫正刑运动的危机及其反动,其基本含义是重重和轻轻二元分立、两极分化,其精神实质是重刑主义。而宽严相济刑事政策的生成背景是对严打刑事政策的反思和纠正,其基本含义是根据犯罪的严重程度和犯罪人的人身危险性大小实行宽区别对待、宽严互济、互补,其精神实质是宽严适度、侧重宽缓。 相似文献
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Sugawara S 《Journal of forensic sciences》2007,52(4):974-977
In this study, a new nondestructive technique for passport examination is proposed. In this technique, linearly polarized light is used to measure Fourier transform infrared (FT-IR) reflectance spectra of films on the biographical data page. Thirty genuine and thirty-five counterfeit Japanese passports and five marketed films pasted on name cards were examined. The measured spectra were analyzed as follows. The absorption spectra were obtained by the Kramers-Kronig transformations of reflectance spectra. The peak ratios were then calculated from the absorption spectra by adding the peak areas at 1126 and 1263 cm(-1) and dividing the result by the peak area at 1727 cm(-1). When nonpolarized light was used, the samples could not be distinguished by comparing the peak ratios. However, when polarized light was used, they were successfully distinguished by the comparison. Therefore, polarized light is useful for the forensic discrimination of passport films by the measurement of FT-IR spectra. 相似文献
19.
Sowmya Kasetty B.D.S. M.D.S. M. Rammanohar B.D.S. M.D.S. T. Raju Ragavendra B.D.S. M.D.S. 《Journal of forensic sciences》2010,55(3):779-783
Abstract: Dental hard tissues are good candidates for age estimation as they are less destructive and procedures to determine age can be easily performed. Although cementum annulations and cementum thickness are important parameters in this regard, they are seldom used. This study was undertaken to review the methods, difficulties in execution of techniques, and accuracy of cementum thickness and annulations in estimating the age. Unstained and stained ground sections of tooth were used to measure cemental thickness and count cemental annulations based on which age was estimated and was compared with known age. Although there was positive relation between cemental thickness and annulations with age, only in 1–1.5% of cases, age could be predicted with accuracy. 相似文献
20.
Kelly M. Brinsko M.S. 《Journal of forensic sciences》2010,55(4):915-923
Abstract: Fibers that are termed “eco‐friendly” or “biodegradable” by manufacturers are increasingly being used in textile products such as apparel and carpeting to appeal to the ever more environmentally aware public. As such, these modern fibers are expected to begin showing up more often in forensic casework, and it is important that the forensic examiner recognize them. This study employed polarized light microscopy (PLM) and Fourier transform infrared (FTIR) microspectroscopy to characterize selected fibers of azlon, polylactic acid (PLA), cellulose composites of alginate or chitin, and bamboo (viscose rayon). Fiber cross‐sections, refractive indices, melting points, solubilities, and FTIR measurements were conducted. Results indicate that the azlons and PLA fibers are easily distinguishable from other textile fibers by their optical and chemical properties. The cellulose composites show only small differences in comparison with other cellulose‐based fibers, while bamboo viscose rayon is indistinguishable from normal viscose rayon. 相似文献