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61.
The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons. 相似文献
62.
Hashimoto T Howitt DG Land DP Tulleners FA Springer FA Wang S 《Journal of forensic sciences》2007,52(5):1082-1088
The discrimination of noncolored transparent polyethylene bags was studied by several nondestructive and semidestructive analytical methods. X-ray diffraction, infrared spectroscopy, and optical microscopy (differential interference contrast microscopy and phase contrast microscopy) were applied to polyethylene films. X-ray diffraction was used to distinguish variations in the crystalline phase, infrared spectroscopy was used to distinguish variations in the molecular components, and optical microscopy was used to distinguish the different surface morphologies. The results show that X-ray diffraction classifies the crystalline phase of the film depending on whether it is made from low-density polyethylene, linear low-density polyethylene, or high-density polyethylene; that infrared spectroscopy is useful to distinguish the molecular components and it is the most discriminating technique; and that optical microscopy discriminate films easily by their morphological differences. 相似文献
63.
Rachel M. Krause 《政策研究评论》2012,29(5):585-604
Much of the attention surrounding local climate protection in the United States is associated with two networks: ICLEI Local Governments for Sustainability's Cities for Climate Protection and the U.S. Conference of Mayors’ Climate Protection Agreement (MCPA). However, the impact of these networks on member‐city actions has not been clearly established. This paper examines whether, and to what extent, participation in climate networks leads to the implementation of greenhouse gas (GHG)‐reducing policies, above and beyond what would have been done in their absence. To account for the possibility that cities which join climate networks are systematically different from those that do not and control for self‐selection induced bias, three statistical techniques—propensity score matching, Heckman full information maximum likelihood, and instrumental variables—are employed to estimate the “treatment effect” of participation. Results suggest that impact is network specific: ICLEI membership causes small to moderate increases in cities’ GHG‐relevant activity, whereas the MCPA has no such effect. The characteristics of each network are evaluated in light of these findings. 相似文献
64.
65.
How does the American public assess risk when it comes to national security issues? This paper addresses this question by analyzing variation in citizen probability assessments of the terrorism risk of nuclear power plants. Drawing on the literature on how motivated reasoning, selective information processing, and domain‐specific knowledge influence public opinion, we argue that heterogeneous issue preferences and knowledge of nuclear energy and homeland security have important explanatory power. Using original data from a unique 2009 national survey in the United States, we show that Americans are divided in their probability assessments of the terrorism risk of nuclear power plants. Consistent with our theoretical expectations, individuals who support using nuclear power to meet rising energy demands, who are generally less concerned with terrorism, or who are more knowledgeable about terrorism and nuclear security tend to provide lower assessments of the likelihood that nuclear power plants increase terrorist attacks, and vice versa. The findings have implications for the literature on public opinion, risk assessment, energy policy and planning, and homeland security. 相似文献
66.
《Journal of Baltic studies》2012,43(2):99-121
Germany and Russia have agreed to build the Nord Stream gas pipeline. The 1,200 kilometers-long structure will run from Vyborg, Russia to Greifswald, Germany traversing the Baltic Sea. The Baltic countries, Finland, Poland and Sweden, have expressed concerns about the project. At issue is the environmental impact of the project as well as the energy, political, and socioeconomic implications. 相似文献
67.
我国从国外引进的合同能源管理是一种推广节省能源新技术的模式,在实际运行中需要协调与整合技术、资金、设施建设与项目管理等多方面的关系,因而,我国对合同能源管理、能源管理合同属性的认识比较模糊,并存在多种看法。为此,必须厘清合同能源管理所涉及的法律关系,充分解析能源管理合同的法律属性,分析把握合同能源管理运营中资产等所有权归属问题,在我国现有法律体系框架范围内,正确、有效地调整合同能源管理关系,积极促进节能新技术在全社会的推广、普及。 相似文献
68.
Estimation of the time since death (postmortem interval [PMI]) is one of the most difficult problems in forensic investigations, and many methods currently are utilized to estimate the PMI. The goal of this study was to investigate the changes of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra of rat brain from postmortem time 0-144 h. The intensity ratios of major absorbance bands were examined (I(1066)/I(1392), I(1168)/I(1392), I(1234)/I(1454), I(1301)/I(1392), I(1647)/I(2956), I(2921)/I(2850), and I(1647)/I(1539)). The spectra of rat brain displayed prominent changes with increasing PMI. The band at 2871 and 1737 per cm became weak with the time increasing and even disappeared at postmortem 96 and 72 h, respectively. A close linear correlation was shown between the relative absorption intensity and the PMI, and the I(1234) /I(1454) offered a stronger correlation (r = 0.973). Our results indicate that ATR-FTIR spectroscopy may be a useful technique for estimating the PMI. 相似文献
69.
Yingfang Zou BSc Aolin Zhang BSc Xiaobin Wang PhD Lei Yang MSc Meng Ding PhD 《Journal of forensic sciences》2024,69(2):584-592
The identification of different kinds of watercolor inks is an important work in the field of forensic science. Four different kinds of watercolor ink Spectroscopy data fusion strategies (Fourier Transform Infrared spectroscopy and Raman spectroscopy) combined with a non-linear classification model (Extreme Learning Machine) were used to identify the brand of watercolor inks. The study chose Competitive Adaptive Reweighted Sampling (CARS), Random Frog (RF), Variable Combination Population Analysis-Genetic Algorithm (VCPA-GA), and Variable Combination Population Analysis-Iteratively Retains Informative Variables (VCPA-IRIV) to extract characteristic variables for mid-level data fusion. The Cuckoo Search (CS) algorithm is used to optimize the extreme learning machine classification model. The results showed that the classification capacity of the mid-level fusion spectra model was more satisfactory than that of single Infrared spectroscopy or Raman spectroscopy. The CS-ELM models based on infrared spectroscopy used to recognize the watercolor ink according to brands (ZHENCAI, DELI, CHENGUANG, and STAEDTLER) obtained an accuracy of 66.67% in the test set using all spectral datasets. The accuracy of CS-ELM models based on Raman spectroscopy was 67.39%. The characteristic wavelength selection algorithms effectively improved the accuracy of the CS-ELM models. The classification accuracy of the mid-level spectroscopy fusion model combined with the VCPA-IRIV algorithm was 100%. The data fusion method increased effectively spectral information. The method could satisfactorily identify different brands of watercolor inks and support the preservation of artifacts, paintings, and forensic document examination. 相似文献
70.
Yun Sik Nam Ph.D. Jin Sook Park M.S. Yeonhee Lee Ph.D. Kang‐Bong Lee Ph.D. 《Journal of forensic sciences》2014,59(3):800-805
Questioned documents examined in a forensic laboratory sometimes contain signatures written with ballpoint pen inks; these signatures were examined to assess the feasibility of micro‐attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy as a forensic tool. Micro‐ATR FTIR spectra for signatures written with 63 ballpoint pens available commercially in Korea were obtained and used to construct an FTIR spectral database. A library‐searching program was utilized to identify the manufacturer, blend, and model of each black ballpoint pen ink based upon their FTIR peak intensities, positions, and patterns in the spectral database. This FTIR technique was also successfully used in determining the sequence of homogeneous line intersections from the crossing lines of two ballpoint pen signatures. We have demonstrated with a set of sample documents that micro‐ATR FTIR is a viable nondestructive analytical method that can be used to identify the origin of the ballpoint pen ink used to mark signatures. 相似文献