As to their optical properties, the components of human skin can be divided into two different categories: the light-scattering components shown as peaks and those absorbing light appearing as dips ...in the reflectance spectrum. As the post-mortem interval progresses, the concentration of scatterers and absorbers and thus the reflectance spectra change due to post-mortem tissue breakdown and degradation. Based on a total number of 532 reflectance spectrometric measurements in 195 deceased, a characteristic change in the reflectance spectra could be documented in the post-mortem course. Subsequently, an algorithm to calculate the post-mortem interval was developed by analysing the reflectance spectrometric extrema.
Abstract During a Christmas party, two male guests started fighting. The perpetrator was allegedly pushed onto a glass table by the victim or fell into the table together with that man so that the ...glass top broke and caused a cut wound on the perpetrator's back. According to his statement he then threw a fragment of the broken glass table in the direction of the other man hitting him accidentally in a way so that the subclavian artery was severed and he died from exsanguination. Tests on the breaking characteristics of the glass table, the flying behaviour and the kinetics of thrown glass fragments conducted on various models supported the conclusion that the fatal injury on the victim's neck could not have been caused by a thrown glass fragment. It was much more likely that a stab with a blade-shaped glass fragment was the cause of the fatal injuries.
Background
Novel anti-angiogenic treatments are increasingly complementing established cancer therapy strategies in head and neck tumors. Contrast-enhanced magnetic resonance imaging (MRI) can be ...applied for early and non-invasive therapy monitoring by non-invasive quantitative assessment of tumor microcirculation as in vivo imaging biomarkers of therapy response.
Purpose
To monitor the anti-angiogenic effects of a novel combination therapy on experimental head and neck squamous cell carcinomas (HNSCC) with dynamic contrast-enhanced (DCE)-MRI.
Material and Methods
Athymic rats (n = 18) with subcutaneous HNSCC xenografts were investigated by DCE-MRI before and after 7 days of a daily triple therapy regimen combining the COX-II-inhibitor celecoxib, the matrix-metalloproteinase-inhibitor GM6001, and the uPA-inhibitor upamostat. Quantitative measurements of tumor blood flow (tBF), tumor blood volume (tBV), and permeability-surface area product (PS) were calculated and validated by immunohistochemistry.
Results
Mean tBF and tBV in triple-therapy animals decreased significantly from day 0 to day 7 (tBF, 41.0 ± 14.2 to 20.4 ± 5.7 mL/100 mL/min; P < 0.01; tBV, 17.7 ± 3.9 to 7.5 ± 3.3%; P < 0.01). No significant effects on PS were observed in either group (P > 0.05). Immunohistochemical analysis showed a significantly lower tumor vascularity in the therapy group than in the control group (CD31), significantly fewer Ki-67+ proliferating tumor cells and significantly more Capase-3+ apoptotic tumor cells (P < 0.05). Significant (P < 0.05) correlations were observed between tBF/tBV and CD31 (tBF, r = 0.84; tBV, r = 0.70), tBV and Ki-67 (r = 0.62), as well as tBF and caspase-3 (r = −0.64).
Conclusion
DCE-MRI may be a suitable tool for the non-invasive monitoring of the anti-vascular effects of this innovative triple therapy regimen with potential for clinical translation.
Diabetic ketoacidosis (DKA) is a metabolic complication of diabetes mellitus that takes a lethal course if untreated. In this way relevant to forensic medicine, secure diagnosis of DKA usually ...involves the evidence of elevated levels of glucose and the ketone bodies acetone, acetoacetate, and β-hydroxybutyrate in corpse fluids. We conducted a postmortem hydrogen proton magnetic resonance spectroscopy (
H-MRS) in a case of lethal DKA. Distinctive resonances of all three ketone bodies as well as glucose were visible in spectra of cerebrospinal fluid, vitreous humor, and white matter. Estimated concentrations of ketone bodies and glucose supported the findings both of autopsy and biochemical analysis. Advantages of human postmortem
H-MRS are the lack of movement and flow artifacts as well as lesser limitations of scan duration. Postmortem
H-MRS is able to non-invasively measure concentrations of glucose and ketone bodies in small volumes of various regions of the brain. It may thus become a diagnostic tool for forensic investigations by quick determination of pathological metabolite concentrations in addition to conventional autopsy.
Abstract At a party of a sports club, an argument started between two groups of young men, in the course of which one of the persons involved threw a beer glass hitting a young man of the other ...group, who collapsed with a profusely bleeding wound. Although resuscitation measures were initiated immediately, the victim died at the scene due to exsanguination from the completely severed left external carotid artery in combination with the aspiration of blood. Tests with drinking glasses thrown at a skull–neck model suggested that an undamaged beer glass thrown at the head of the victim could not cause the fatal injuries on the neck because of its splintering behaviour. In fact, it seemed that the beer glass had been damaged prior to throwing it and that its sharp edges perforated the skin on hitting the neck.
Reflectance spectrometry is a fast and reliable method for the characterization of human skin if the spectra are analyzed with respect to a physical model describing the optical properties of human ...skin. For a field study performed at the Institute of Legal Medicine and the Freiburg Materials Research Center of the University of Freiburg, a scientific information repository has been developed, which is a variant of an electronic laboratory notebook and assists in the acquisition, management, and high-throughput analysis of reflectance spectra in heterogeneous research environments. At the core of the repository is a database management system hosting the master data. It is filled with primary data via a graphical user interface (GUI) programmed in Java, which also enables the user to browse the database and access the results of data analysis. The latter is carried out via Matlab, Python, and C programs, which retrieve the primary data from the scientific information repository, perform the analysis, and store the results in the database for further usage.
Line attributes such as width and dashing are commonly used to encode information. However, many questions on the perception of line attributes remain, such as how many levels of attribute variation ...can be distinguished or which line attributes are the preferred choices for which tasks. We conducted three studies to develop guidelines for using stylized lines to encode scalar data. In our first study, participants drew stylized lines to encode uncertainty information. Uncertainty is usually visualized alongside other data. Therefore, alternative visual channels are important for the visualization of uncertainty. Additionally, uncertainty -- e.g., in weather forecasts -- is a familiar topic to most people. Thus, we picked it for our visualization scenarios in study 1. We used the results of our study to determine the most common line attributes for drawing uncertainty: Dashing, luminance, wave amplitude, and width. While those line attributes were especially common for drawing uncertainty, they are also commonly used in other areas. In studies 2 and 3, we investigated the discriminability of the line attributes determined in study 1. Studies 2 and 3 did not require specific application areas; thus, their results apply to visualizing any scalar data in line attributes. We evaluated the just-noticeable differences (JND) and derived recommendations for perceptually distinct line levels. We found that participants could discriminate considerably more levels for the line attribute width than for wave amplitude, dashing, or luminance.
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