Analysis of false starts lesions on human bones produced by two hand saws with high TPI.

Cases of criminal dismemberment are encountered in forensic pathology and forensic anthropology. Saw mark analysis aims to determine the type of saw that was used: hand saw versus electrical saw, crosscut and universal saw versus rip saw, size of the teeth ("teeth per inch" TPI), and set type. The goal of this study was to analyze using a stereomicroscope a series of 60 experimental false starts (30 lesions for each saw) produced on human bones by two different handsaws with a high TPI (15 and 32). The lesions caused by these high TPI saws have rarely been described in the forensic literature. Saw 2 (rip hacksaw with a 32 TPI and a wavy set) displayed classical features. In contrast, saw 1 (universal panel saw, TPI 15, alternating set) did not produce the expected characteristics: the minimum width of the kerf was weak, the kerf walls were straight, the striae were straight, and the kerf profile was very peculiar with a succession of peaks and dips that has not yet been described.

Analysis of false start bone lesions produced by an electrical oscillating autopsy saw.

Postmortem dismemberment results from the use of sharp or sharp blunt instruments. Saws produce specific bone lesions, and the observation of certain saw mark features allows for the recognition of certain characteristics of the saw and its teeth. At autopsy, sections of the skull and other parts of the skeleton are usually achieved using an electrical oscillating autopsy saw. In cases of dismemberment, this autopsy saw may create additional marks to those produced by the criminal activity. In order to help the forensic pathologist to differentiate the two types of marks, this experimental study used a stereomicroscope to examine 130 experimental false starts produced on animal and human bones by an oscillating autopsy saw. A flagrant succession of narrow and wide aspects of the walls (in a "figure of 8" shape), with obvious oval bone islands and undulating striae are patterns typically left behind by oscillating autopsy saws, but the depth of the false starts plays an important role in the variation of the features. In particular, superficial false starts tend to be associated with larger kerf widths, straight walls, and longitudinal bone islands.

Sprint start performance: the potential influence of triceps surae electromechanical delay.

In the sprint start, a defined sequence of distinct response delays occurs before the athlete produces a movement response. Excitation of lower limb muscles occurs prior to force production against the blocks, culminating in a movement response. The time delay between muscle excitation and movement, electromechanical delay (EMD), is considered to influence sprint start response time (SSRT). This study examined the delay in sprint start performance from EMD of the triceps surae muscle and examined whether certain sprinters gain an advantage in SSRT. Nineteen experienced sprinters performed sprint starts from blocks, with SSRT measured by an International Association of Athletics Federations (IAAF)-approved starting block system. EMD times were detected during a heel-lift experiment. Using revised SSRT limits, based on concerns over the validity of the IAAF 100 ms false start limit, EMD produced a significant moderate correlation with SSRT (r = 0.572, p = 0.011). Regression analysis determined that together, EMD and signal processing time (the delay between the auditory signal and muscle excitation) accounted for 37% of the variance in SSRT. Initial results suggest EMD is part of the response time process and that certain athletes may gain a performance advantage due to reduced EMD.

Advantages of micro-CT in the case of a complex dismemberment.

This case study reports the advantages of micro-CT to aid the investigative process in a complex dismemberment case. Micro-CT was successfully implemented to scan all skeletal remains of a dismembered female. The digital models were utilized to (i) screen for any further injuries not related to the dismemberment, (ii) provide measurements from false starts non-destructively, and (iii) visually represent the evidence in a structured format in court to improve the understanding of the forensic evidence by the jury. Acquiring high-resolution scans in this manner improved the efficiency of the forensic investigation by screening the remains and provided complementary toolmark evidence to the investigating team and forensic pathologist. A total of 14 false starts were identified along with the directionality of each dismemberment cut. Furthermore, the visual 3D representation of the remains in court provided a powerful tool to communicate this important evidence to the jury and form a prosecution narrative. As a forensic radiological method, micro-CT provided valuable information both in the investigation and the court presentation.

Investigating false start of the main growing season: A case of Uganda in East Africa.

False start of the growing season (Fsos) is a component of the onset variability related to agronomic drought that adversely impact on agricultural production and productivity. In the sub-Saharan Africa (SSA) where agriculture heavily depends on rainfall, the Fsos tends to create confusion among farmers on when to start planting crops thereby affecting seed germination and normal growth after emergence. In this paper, we focus on the Fsos and the occurrence of dry spell especially before the Start of growing Season (SoS). We take advantage of the existing rainfall estimates (CHIRPS) and remotely sensed data for vegetation performance (NDVI) over the period 1999-2017 in combination with local knowledge derived from farmers to map out areas at risk of (i) dry spell at the SoS, and (ii) false timing of SoS or high probability of occurrence of the Fsos. We found that the North Eastern part of Uganda (8.8% of arable area) were at risk of dry spell throughout each year. However, the greater North (58.1% of arable area) was prone to dry spell during the onset of the March-May season. Areas in the South Western (3.7%) region were at risk during the onset of the September-November season. The probability that a location in Uganda experiences an Fsos falls between 0-53%. The findings in this study are vital for planning of predictive adaptation to the impacts of climate variability on agriculture amid struggle aimed at tackling food insecurity challenge in the SSA.

Correlation between saw blade width and kerf width.

Most studies of saw marks have focused on morphological characteristics and their utility in identifying saws suspected to have been utilized in cases of criminal dismemberment. The present study examined the extent to which metric analysis may be used to correlate saw blade measurements with minimum kerf widths (MKWs). A sample of 56 partially defleshed white-tailed deer (Odocoileus virginianus) long bones was utilized as proxy for human remains. The long bones were cut using a variety of commercially available saws, including 11 manual-powered and 5 mechanical-powered saws. A total of 496 false start kerfs (FSKs) were created. Two experiments were performed, with the first test examining the MKWs of FSKs produced on specimens that were restrained using a bench vise, while the second test analyzed the MKWs of FSKs produced on minimally restrained specimens. Statistical analysis using Hierarchical Linear Modeling (HLM) indicated a positive relationship between saw blade width (mm) and MKW, with blade width (p < 0.001) and the overall difference between the mechanical- and manual-powered saws (p = 0.029) tested, reaching statistical significance. A comparison of MKWs produced using manual-powered saws on restrained and minimally restrained bones suggests that restraint condition (p = 0.009) has a statistically significant effect. In comparisons of MKWs to blade widths, the average ratio for mechanical-powered saws is 18.7% greater than the average ratio for manual-powered saws. While the mode of the ratios was 1.42, thus supporting the general rule that MKW does not exceed 1.5 times blade width, multiple individual ratios did surpass 1.5.