To describe the current state of research and future research hotspots through a metrological analysis of the literature in the field of forensic anthropological remains identification research.
Abstract The nature of K‐feldspars of four soils developed from glacial till deposits and lacustrine sediments in Saskatchewan, Canada was studied. The K‐feldspars from the size fractions 20‐2,000µ were concentrated by heavy liquid separation at a specific gravity of 2.59. X‐ray diffraction analysis was used to identify orthoclase and microcline, to estimate the proportion of orthoclase to microcline, and to determine the obliquity of microcline. The K‐feldspars in the size fractions 50 to 2,000µ of certain soils were further studied by optical microscope and electron microprobe methods. The proportion of orthoclase to microcline increased with decrease in particle size. In the comparable size fractions of the soils developed from the glacial till deposits, the proportion of orthoclase to microcline increased from north to south in the region under study. The proportion of orthoclase to microcline was higher in the Orthic Black soil developed from the lacustrine sediments than in the Orthic Black soil developed from glacial till deposits. The data obtained show the bearings of soil parent material on the relative abundance of orthoclase to microcline. The obliquity values range from 0.81 to 0.89, indicating a high degree of exsolution. The presence of perthite, as revealed by X‐ray data, optical microscope, and electron microprobe studies, further elucidate the nature of exsolution.
Structural heterogeneity in the vadose zone can significantly influence the dynamics of surface and subsurface distribution of water. It is one important reason for the patterned crops in fields. GPR as a non-invasive tool facilitates the quick investigation of subsurface structures and associated soil water contents of agricultural lands. A field study site with patterned wheat was surveyed at 1.5 m line spacing using 400 MHz multichannel GPR. Through time-lapse snapshots of the ground with multi-channel GPR and surface TDR measurements after a heavy rainfall event, we (i) determine the subsurface 3D architecture, (ii) simultaneously measure the depth-averaged soil water content, and (iii) assess the influence of the structural heterogeneity on the surface and subsurface soil water redistribution. Through investigating the field-scale soil water dynamics, we discuss the relationship between soil architecture and the patterned crops in hydrological perspective. Results demonstrate that multi-channel GPR allows the collection of valuable information about the subsurface structure and soil water dynamics at site-specific land.
The researches on postmortem interval （PMI） estimation are very important and meaningful in forensic science. PMI estimation is also an important issue that must be solved in practice of forensic pathology. There are many defects existing in traditional methods for PMI estimation, so it is imperative to introduce new pathways. With the emergence of various new technologies, the researches on PMI estimation have a tendency from simple to complex with a growth of data. The present review firstly summarizes a series of methods used for PMI estimation, and then gives an outlook for the application of artificial intelligence algorithms in this field.死亡时间推断最新研究与展望.死亡时间推断相关研究在法医学领域中有着极为重要的地位和意义，一直是法医病理学实践中亟待解决的重大问题之一。传统的方法与手段存在许多缺陷，新方法的引入势在必行。随着各种新技术的涌现，关于死亡时间推断的研究有着从简单到复杂的趋势，数据量也随之不断增长。本文首先总结了既往死亡时间推断的方法，最后对基于大数据人工智能算法在法医学死亡时间推断研究中的应用进行了展望。.法医病理学；死亡时间；大数据；人工智能；综述
The aim of this study was to investigate the changes of Fourier transform infrared (FT-IR) spectra of rat liver and spleen tissues from time zero to 144 h postmortem. The absorbance (Ax represents the infrared absorbance at wavenumber x cm−1) ratios of major absorbance bands were examined. A 3303/A 2925, A 1647/A 1541 (liver), A 1238/A 1338, A 1153/A 1338 (liver), A 1080/A 1338, and A 1030–1050/A 1338 (liver) showed a decrease postmortem, whereas the A 1396/A 1456 ratio (spleen) showed an increase. Furthermore, these absorbance ratios showed a strong linear relationship with increasing time postmortem, and the A 1238/A 1338 ratio of spleen offered a stronger correlation (R 2 = 0.88) than did the others. A new absorbance band appeared at 1120 cm−1 for the liver and spleen at 120 h postmortem and another new band appeared at 1170 cm−1 for the liver, but the existing absorbance band at 1170 cm−1 disappeared in the spleen. Our initial results demonstrate that the quantitative analysis of FT-IR spectrum related to postmortem interval (PMI) shows a strong linear correlation between absorbance ratios and increasing time after death. The FT-IR changes of spectra and absorbance ratios can support further study for estimating short-term and long-term PMI. Upon future validation, FT-IR can offer advantages in combination with established methods to improve PMI estimation.
To analyse the Fourier transform infrared （FTIR） spectral data of renal tissue at different temperatures in rats after death, and to explore the effects of temperature on the FTIR spectral characteristics of renal tissue.The rats were sacrificed by cervical dislocation and placed at 4 ℃, 20 ℃ and 30 ℃. The FTIR spectral data of renal tissue were collected at different time points and analysed by data mining method.The principal component analysis （PCA） results showed that there were significant trends of clustering in the samples of partial time point at 4 ℃, 20 ℃ and 30 ℃. Partial least square （PLS） regression models were established with the spectral data at three temperature groups. The performance of PLS regression models in 20 ℃ and 30 ℃ groups were more superior than that in 4 ℃ group, and the stability of the model in 20 ℃ group was better than that in 30 ℃ group.There are differences in the FTIR spectral characteristics of renal tissue of rats after death at different temperatures. Temperature has a major impact on the performance of FTIR spectral PLS regression model. Therefore, in order to improve the accuracy of postmortem interval estimation, the effects of temperature on the model should be considered in the related study by spectral method.
Traumatic axonal injury (TAI) is a progressive and secondary injury following traumatic brain injury (TBI). Despite extensive investigations in the field of forensic science and neurology, no effective methods are available to estimate TAI interval between injury and death. In the present study, Fourier transform IR (FTIR) spectroscopy with IR microscopy was applied to collect IR spectra in the corpus callosum (CC) of rats subjected to TAI at 12, 24, and 72 h post-injury compared with control animals. The classification amongst different groups was visualized based on the acquired dataset using hierarchical cluster analysis (HCA) and partial least square (PLS). Furthermore, the established PLS models were used to predict injury interval of TAI in the unknown sample dataset. The results showed that samples at different time points post-injury were distinguishable from each other, and biochemical changes in protein, lipid, and carbohydrate contributed to the differences. Then, the established PLS models provided a satisfactory prediction of injury periods between different sample groups in the external validation. The present study demonstrated the great potential of FTIR-based PLS algorithm as an objective tool for estimating injury intervals of TAI in the field of forensic science and neurology.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)