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1.
Attempts to prevent illegal trade in bile and gallbladders from Asiatic black bears, Ursus thibetanus, are hampered by difficulties associated with identifying such items. We extracted DNA from bile crystals of unknown species origin and generated partial cytochrome b (cyt b) sequences using either universal primers (positioned in conserved regions of cyt b), or primers designed on existing U. thibetanus sequences (UT). Species origin was determined by aligning resolved sequences to reference sequence data. The universal primers were unsuitable for U. thibetanus identification when multiple species templates were present in the samples. The UT primers amplified U. thibetanus DNA from all sample extracts, including those containing mixed species templates. The amplified fragment can distinguish U. thibetanus from the most closely related species, U. americanus, a distinct advantage of DNA sequencing over the methods currently used to analyze suspected U. thibetanus bile.  相似文献   

2.
Environmental risks from US military construction on the atollof Diego Garcia (British Indian Ocean Territory) since 1971include damage caused by large-scale ‘coral mining’,the introduction of invasive alien plant species, continuoustransits of nuclear material and unreported major fuel spills;these risks are now compounded by those of sea-level rise andocean acidification due to global climate change. The US andUK governments have evaded accountability by way of a persistent‘black hole’ strategy, contending that some nationallaws and international treaties for the protection of humanrights and the environment do not apply to the island—aposition confirmed by a controversial appellate judgment ofthe House of Lords in October 2008, essentially relying on ‘prerogative’colonial law. This article draws attention to the fallacy ofthe black-hole syndrome, and to its potentially fatal consequencesfor the British claim to a 200-mile environment protection zonein the Chagos Archipelago.  相似文献   

3.
This study applies Raman microspectroscopy to differentiate the chemical components in printing inks of different brands, colors, and type using the 532 nm and 785 nm excitation wavelengths. Spectra were collected from 319 inks (78 inkjet, 76 toner, 79 offset, and 86 intaglio) representing various colors. Comparisons were performed to calculate discrimination capability percentages for each ink type. Overall, Raman microspectroscopy differentiates according to the following hierarchy: intaglio (96%), inkjet (92%), offset (90%), and toner (61%). The ability of Raman microspectroscopy to differentiate between same‐colored inks from different brands was dependent on the color and ink analyzed. Based on ink color, the discrimination capability ranged from 75 to 94% (inkjet), 0 to 86% (toner), and 0 to 77% (offset). Copper phthalocyanine was detected in cyan inks and various intaglio inks, while carbon black was identified in black inkjet, offset, and intaglio inks.  相似文献   

4.
Fatal choking in infants and children   总被引:2,自引:0,他引:2  
Food asphyxiation in infants/children follows a different pattern from the adult "cafe coronary." In the absence of ethanol intoxication, infants/children are prone to mishandling nonfriable, firm, slippery foods/objects with a rounded contour. The Dade County Medical Examiner's files were searched from 1956 to mid-1983 for accidental pediatric choking deaths. Seventeen food and six foreign body asphyxiations were found. The male/female ratio was 1.4/1 and 1/1, respectively. The white/black ratio was 0.9/1 for food asphyxiation whereas no black victims were encountered choking upon foreign objects. Seventy-eight percent of all victims were between 2 months and 4 years of age. Infants/children asphyxiated on items such as a hot dog, hard candy, peanut, toy rattle, tissue paper, balloon, marble, etc. The choking event was recognized by nearby adults in most instances. Risk factors include the availability of riskful foods/objects, natural diseases with difficulty feeding, poor eating habits, and uneducated or ignorant parents/others at the scene. Although public education, package labeling, and changes in food/object design may be appropriate, the ubiquituous risk foods and small foreign objects will, on occasion, escape the eye of even the most watchful parent.  相似文献   

5.
Using discriminant function analysis, classification accuracies for ancestry and sex in white and black South Africans were compared using North American (FDB), African groups in Howells (HDB), and South African (SADB) databases in FORDISC 3.0. (FD3). Twenty‐four standard linear measures were collected from a total of 86 black and 101 white crania obtained from the Pretoria Bone Collection. White and black South Africans classified 73% correctly in FDB, 55% correctly in HDB, and 71% correctly in SADB. The percentage of atypical cases was higher with FDB than SADB. In all three databases, misclassification occurred more with sex than ancestry revealing differences in sexual dimorphism between population groups. Broad ancestral differences may explain low misclassification rates for ancestry. FD3, with a modern South African reference sample, can assist South African anthropologists to standardize methodology and to justify procedures for estimating ancestry.  相似文献   

6.
The present study investigates the frequency of bifidity/nonbifidity in the black and white South African populations. Four-hundred skeletons of known race, sex, and tribal group were examined. Spinous processes were classified as bifid (bifurcate and cleft subtypes) and nonbifid (obtuse, pediculate, acinate, and clavate subtypes). Statistical analysis using the chi-squared probability test (p < 0.05) was carried out. Bifid spinous processes were present significantly more frequently in the white sample (58.9%) than in the black (31.6%). A bifid spinous process occurred most commonly in C2 (89%) followed by C5 (83%), C4 (79%), C3 (59.4%), and C6 (41.7%) in the white sample. A similar order of decrease in bifidity occurred in the black sample. C2 most commonly displayed the bifurcate subtype of spinous process, while the clavate subtype of nonbifid spinous process was the most common in both populations. The significantly higher frequency of bifidity in the white South African sample when compared to the black sample may suggest a population difference.  相似文献   

7.
The effect of electron beam irradiation on a series of different writing inks is described. As the anthrax-tainted letters were discovered in October 2001, the U.S. government began to experiment with the use of the electron beam irradiation process for destroying such biological agents. Plans initially considered a large-scale countrywide use of this technology. However, over time the scope of this plan as well as the radiation dosage were reduced, especially when some adverse consequences to mailed items subjected to this process were observed. Little data existed at the time to characterize what level of damage might be expected to occur with common items sent through the mail. This was especially important to museums and other institutions that routinely ship valuable and historic items through the mail. Although the Smithsonian Institution initiated some studies of the effect of electron beam irradiation on archived materials, little data existed on the effect that this process would have on forensic evidence. Approximately 97 different black, blue, red, green, and yellow writing inks were selected. Writing ink types included ballpoint, gel, plastic/felt tip, and rollerball. All noncontrol samples were subjected to standard mail irradiation conditions used by the U.S. Postal Service at the time this experiment was performed. A video spectral comparator and thin-layer chromatography (TLC) analysis were used to evaluate both the control and the irradiated samples. Some published studies reported changes in the presence/absence of dye bands in the chromatograms of irradiated writing inks. Some of these studies report the formation of additional dye bands on the chromatogram while others report missing dye bands. However, using standard testing guidelines and procedures, none of the 97 irradiated inks tested were found to show any significant optical or chemical differences from the control samples. In addition, random testing of some of the ink samples using a second solvent system did not reveal any changes. However, one control ink did show some minor changes in optical properties and dye characteristics over time (but not TLC) while the irradiated sample remained stable. Significant changes in the ultraviolet fluorescence characteristics of the irradiated paper samples themselves (not inks) were also observed.  相似文献   

8.
Both black and white populations from Birmingham, Alabama were analyzed for the frequencies of carbonic anhydrase II (CA II), glyoxalase I (GLO) and esterase D (EsD) isoenzymes. The results compared favorably with published frequencies of these genetic markers in other populations.  相似文献   

9.
The purpose of this study was two-pronged: 1) to determine the level of concordance (agreement) between multiple records abstractors who extracted defined data elements from printed medical examiner/coroner (ME/C) death investigation records; and 2) to identify data items for which improved reporting could facilitate the effective use of ME/C reports and data. Four hundred ninety four printed death investigation records were obtained from 224 medical examiner/coroner offices throughout the United States. Trained abstractors were asked to extract information for 110 data elements from investigative reports. Additional data elements for each toxicology workup were abstracted from toxicology laboratory reports and six-digit AIS codes were also abstracted for each injury as described in autopsy reports. The ability of multiple abstractors to identify each data element and identically abstract the data was assessed using Kappa statistical methods. Level of agreement for many data elements was very good (>0.9), but for some data elements agreement was marginal to poor, especially for items related to toxicology, the nature of specific injuries, and dates, times of the occurrence of death and injury. Many data items can be easily abstracted from ME/C records. However, some data items seem difficult to abstract reliably in all cases. Standardizing the report formats used by ME/Cs and/or standardizing the electronic storage of ME/C data would make the abstraction of such data easier and improve the usefulness of ME/C data.  相似文献   

10.
Various vacuum techniques are employed to develop fingermarks on evidentiary items. In this work, a vacuum was used to deposit columnar thin films (CTFs) on untreated, cyanoacrylate-fumed or dusted fingermarks on a limited selection of nonporous surfaces (microscope glass slides and evidence tape). CTF deposition was not attempted on fingermarks deposited on porous surfaces. The fingermarks were placed in a vacuum chamber with the fingermark side facing an evaporating source boat containing either chalcogenide glass or MgF(2). Thermal evaporation of chalcogenide glass or MgF(2) under a 1 μTorr vacuum for 30 min formed dense CTFs on fingermark ridges, capturing the topographical features. The results show that it is possible to capture fingermark topology using CTFs on selected untreated, vacuumed cyanoacrylate-fumed or black powder-dusted nonporous surfaces. Additionally, the results suggested this might be a mechanism to help elucidate the sequence of deposition.  相似文献   

11.
The foreign textile fibers recovered from one item of evidence from each of 20 unrelated crimes in three categories (bank robbery, kidnapping, and homicide) were cross-compared. The items of evidence were scraped to remove the trace evidence and a sample of the collected fibers was examined using a standard scheme of analysis. The fibers were examined with light microscopy (including polarized light microscopy), fluorescence microscopy, and microspectrophotometry. The fibers were divided into natural and manufactured groups and then categorized by color and generic (polymer) class. Cross-comparing all 2083 fibers resulted in 2,168,403 comparisons, after removing duplicate (same fiber) comparisons. Colorless and denim fibers were excluded from this study. No two fibers were found to exhibit the same microscopic characteristics and analytical properties. Therefore, it is rare to find two unrelated items that have foreign fibers that are analytically indistinguishable. These results corroborate other population studies conducted in Europe and target fiber studies conducted both in the US and in Europe.  相似文献   

12.
Political orientation and political attitudes were measured in two independent adult samples. One sample was taken several months before the terrorist attacks on 9/11/01; the other, shortly after. Liberal and conservative participants alike reported more conservative attitudes following 9/11/01 than before. This conservative shift was strongest on two items with the greatest relevance to 9/11/01: George W. Bush and Increasing Military Spending. Marginally significant conservative shifts were observed on two other items (Conservatives, Socialized Medicine), and the direction of change on eight of eight items was in a conservative direction. These results provide support for the motivated social cognition model of conservatism (Jost et al., 2003) over predictions derived from terror management theory (e.g., Greenberg et al., 1992).  相似文献   

13.
Accurate assessment of attitudes about intimate partner violence is important for evaluation of prevention and early intervention programs. Assessment of attitudes about cross-gender interactions is particularly susceptible to bias because it requires specifying the gender of the perpetrator and the victim. As it is likely that respondents will tend to identify with the same-gender actor, items and scales assessing attitudes about intimate partner violence may not have equivalent measurement properties for male and female respondents. This article examines data from 2,575 high school students who participated in a teen-dating violence intervention study. The majority of participants were Latino (91%), and the sample was nearly evenly split with respect to gender (51% female). Items from two scales (boy-on-girl violence, 4 items; girl-on-boy violence, 5 items) reflecting teens' attitudes about dating violence were calibrated with the graded item response theory (IRT) model and evaluated for differential item functioning (DIF) by gender. A total of three items, two from the girl-on-boy violence scale and one from the boy-on-girl violence scale, were identified as functioning differently for girls and boys. In all cases where DIF was detected, the item's attitudinal statement was easier to accept for the gender group that was portrayed as victim rather than perpetrator. For both scales, accounting for the identified DIF influenced inferences about the magnitude of mean differences in attitudes between boys and girls. These results support the use of IRT scores that account for DIF to minimize measurement error and improve inferences about gender differences in attitudes about dating violence.  相似文献   

14.
Hair analysis for ketamine and its metabolites   总被引:4,自引:0,他引:4  
A rapid and sensitive method was developed for the simultaneous identification and quantitation of ketamine (K) and its major metabolite, norketamine (NK) in hair. After decontamination, the hair sample was incubated and extracted, and analyzed by gas chromatography-mass spectrometry (GC-MS). Limits of quantitation were found to be 0.05 ng/mg. Hair segments in black color were collected from 15 K abusers. Based on an experiment with 15 cavies with black, white, and brown hair, the mechanism of incorporation of K into hair was investigated. After shaving hair on the back of the cavies (8 cm x 4 cm), they were separated into three groups and administered intraperitoneally once a day for 7 successive days with high, medium, and low doses of K, respectively. Two days after this, hair segments with different colors were shaved. There was a direct correlation between the concentration of K in cavy hair and the dose and DHNK was detected only in high dosage group. The concentration of K increased in the order of white, brown, and black hair. The possible factors responsible for the incorporation of K and its metabolites in hair were discussed.  相似文献   

15.
Classical test theory approaches to measurement are based upon a number of fairly restrictive assumptions. The nature of these assumptions is such that scales designed to operationalize latent constructs are treated with little regard for the interaction between the human subject and the items that compose the measurement scale. A competing measurement approach, the Rasch model, has been advanced to improve upon the limitations of classical test theory. In this article, the Rasch model was applied to a scale designed to measure Tittle's control balance ratio. Analysis suggests that the original scale and response category options do not meet fundamental measurement. In particular, several items exhibited misfit (and were thus removed from the scale), response category options were reduced from eleven to four, and the scales that form the control balance ratio exhibited very little gender bias. An alternative control balance scale that retains the original items is presented, but this scale no longer summarizes the control balance ratio as one overall score. The implications of these results are addressed.  相似文献   

16.
The U.S. Food and Drug Administration's (FDA) rationale for supporting the development and approval of BiDil (a combination of hydralazine hydrochloride and isosorbide dinitrate; H-I) for heart failure specifically in black patients was based on under-powered, post hoc subgroup analyses of two relatively old trials (V-HeFT I and II), which were further complicated by substantial covariate imbalances between racial groups. Indeed, the only statistically significant difference observed between black and white patients was found without any adjustment for potential confounders in samples that were unlikely to have been adequately randomized. Meanwhile, because the accepted baseline therapy for heart failure has substantially improved since these trials took place, their results cannot be combined with data from the more recent trial (A-HeFT) amongst black patients alone. There is therefore little scientific evidence to support the approval of BiDil only for use in black patients, and the FDA's rationale fails to consider the ethical consequences of recognizing racial categories as valid markers of innate biological difference, and permitting the development of group-specific therapies that are subject to commercial incentives rather than scientific evidence or therapeutic imperatives. This paper reviews the limitations in the scientific evidence used to support the approval of BiDil only for use in black patients; calls for further analysis of the V-HeFT I and II data which might clarify whether responses to H-I vary by race; and evaluates the consequences of commercial incentives to develop racialized medicines. We recommend that the FDA revise the procedures they use to examine applications for race-based therapies to ensure that these are based on robust scientific claims and do not undermine the aims of the 1992 Revitalization Act.  相似文献   

17.
书写材料的无损检验系统研究   总被引:1,自引:1,他引:0  
本研究运用显微分光光度仪、文件检验仪和傅立叶变换拉曼光谱仪三种方法,分别对在中国市场上收集的不同厂家、牌号、型号的35种黑墨水、20种蓝黑墨水、22种蓝墨水、49种黑色墨水笔、30种蓝色墨水笔、45种黑色圆珠笔、和50种蓝色圆珠笔等七组样品进行非破坏检验。结果表明:(1三种非破坏检验方法都能单独对七组样品进行不同程度的鉴别,区分率在50%—94.4%之间;(2)三种方法联用后对黑墨水、蓝黑墨水、蓝墨水、黑色墨水笔、蓝色墨水笔、黑色圆珠笔和蓝色圆珠笔的区分率可分别提高到93.4%、97.3%、99.1%97.2%、97.2%、95.6%和91.8%。通过三种非破坏检验方法的联用,证明它们之间有较强的互补性,最大限度地提高了检验效应,可建立系统的非破坏检验方法。  相似文献   

18.
目的探讨神经心理学检测指标在脑外伤者认知功能障碍评定中的应用价值。方法对脑外伤后认知障碍者进行中国修订韦氏成人智力量表、韦氏记忆量表及计算机化神经行为评价系统部分项目等神经心理学检测,按照原发性损伤程度和专家鉴定结论分别编组,对检测结果进行分析。结果损伤程度组填图、长时记忆、瞬时记忆、视觉保留及视简单反应时项目得分,轻型组高于中、重型组(P<0.05),其余项目(木块图、知识、相似、曲线吻合及数字筛选)组间差异无统计学意义。专家鉴定组中长时记忆、瞬时记忆、视觉保留、视简单反应时、曲线吻合及数字筛选得分值随认知功能障碍程度加重而逐渐降低,其中前4项组间差异具有统计学意义(P<0.05)。而韦氏智力测验4个项目较轻组与较重组得分接近,且均低于中度组,其中3项得分比较具有统计学差异(P<0.05)。结论原发性脑外伤与认知障碍严重程度有一定相关性,但相关检测项目显示不完全平行,在进行鉴定中应选择更为可靠的检测项目。  相似文献   

19.
In 2002 a population study of textile fibres in human hair was carried out using 26 volunteers in Cambridgeshire, UK. Over 12,000 fibres were recovered from a variety of hair lengths using low adhesive tape and classified according to colour, generic type and fibre length. The results of the study showed that the most common fibre colours were black/grey (48%), blue (29.1%) and red (12.7%), the least common being green, orange/brown and yellow which each accounted for less than 5% of the total. Natural fibres (mainly cotton) were predominant (72.3%) and man-made fibres were considerably less frequent. When colour and generic type were classified together, the most common combinations were black and blue cottons. The least common were the man-made fibre/colour combinations with the most frequent of these accounting for less than 7% of the sample. Fibre loads carried by long hair were found to be significantly less than that carried by short hair. The results of this study are in accordance with previous fibre population studies using other types of recipient surfaces and are likely to be influenced by factors such as seasonal and geographical variation.  相似文献   

20.
Score-based approaches for computing forensic likelihood ratios are becoming more prevalent in the forensic literature. When two items of evidential value are entangled via a scorefunction, several nuances arise when attempting to model the score behavior under the competing source-level propositions. Specific assumptions must be made in order to appropriately model the numerator and denominator probability distributions. This process is fairly straightforward for the numerator of the score-based likelihood ratio, entailing the generation of a database of scores obtained by pairing items of evidence from the same source. However, this process presents ambiguities for the denominator database generation - in particular, how best to generate a database of scores between two items of different sources. Many alternatives have appeared in the literature, three of which we will consider in detail. They differ in their approach to generating denominator databases, by pairing (1) the item of known source with randomly selected items from a relevant database; (2) the item of unknown source with randomly generated items from a relevant database; or (3) two randomly generated items. When the two items differ in type, perhaps one having higher information content, these three alternatives can produce very different denominator databases. While each of these alternatives has appeared in the literature, the decision of how to generate the denominator database is often made without calling attention to the subjective nature of this process. In this paper, we compare each of the three methods (and the resulting score-based likelihood ratios), which can be thought of as three distinct interpretations of the denominator proposition. Our goal in performing these comparisons is to illustrate the effect that subtle modifications of these propositions can have on inferences drawn from the evidence evaluation procedure. The study was performed using a data set composed of cursive writing samples from over 400 writers. We found that, when provided with the same two items of evidence, the three methods often would lead to differing conclusions (with rates of disagreement ranging from 0.005 to 0.48). Rates of misleading evidence and Tippet plots are both used to characterize the range of behavior for the methods over varying sized questioned documents. The appendix shows that the three score-based likelihood ratios are theoretically very different not only from each other, but also from the likelihood ratio, and as a consequence each display drastically different behavior.  相似文献   

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