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Steven A. Symes is primarily known for his scholarly work on skeletal trauma analysis and for his applied casework and frequent courtroom appearances providing forensic anthropology testimony. However, many may not know that throughout his career Steve has also been a proponent of photography and microscopy. This biography serves to introduce some and enlighten others as to how Steve ended up in forensic anthropology, highlighting aspects of Steve as a mentor, colleague, and friend. This manuscript is based on a chat between the authors, with some details filled in via supporting documents and colleagues.

Background: The utilization of exogenous fatty acids by Gram-negative bacteria has been linked to many cellular processes, including fatty acid oxidation for metabolic gain, assimilation into membrane phospholipids, and control of phenotypes associated with virulence. The expanded fatty acid handling capabilities have been demonstrated in several bacteria of medical importance; however, a survey of the polyunsaturated fatty acid responses in the model organism Escherichia coli has not been performed. The current study examined the impacts of exogenous fatty acids on E. coli. Results: All PUFAs elicited higher overall growth, with several fatty acids supporting growth as sole carbon sources. Most PUFAs were incorporated into membrane phospholipids as determined by ultra performance liquid chromatography-mass spectrometry, whereas membrane permeability was variably affected as measured by two separate dye uptake assays. Biofilm formation, swimming motility and antimicrobial peptide resistance were altered in the presence of PUFAs, with arachidonic and docosahexaenoic acids eliciting strong alteration to these phenotypes. Conclusions: The findings herein add E. coli to the growing list of Gram-negative bacteria with broader capabilities for utilizing and responding to exogenous fatty acids. Understanding bacterial responses to PUFAs may lead to microbial behavioral control regimens for disease prevention.

Metabolomics is an intriguing field of study providing a new readout of the biochemical activities taking place at the moment of sampling within a subject's biofluid or tissue. Metabolite concentrations are influenced by several factors including disease, environment, drugs, diet and, importantly, genetics. Metabolomics signatures, which describe a subject's phenotype, are useful for disease diagnosis and prognosis, as well as for predicting and monitoring the effectiveness of treatments. Metabolomics is conventionally divided into targeted (i.e., the quantitative analysis of a predetermined group of metabolites) and untargeted studies (i.e., analysis of the complete set of small-molecule metabolites contained in a biofluid without a pre-imposed metabolites-selection). Both approaches have demonstrated high value in the investigation and understanding of several monogenic and multigenic conditions. Due to low costs per sample and relatively short analysis times, metabolomics can be a useful and robust complement to genetic sequencing.

Evaluation of decomposed individuals by forensic pathologists is a common occurrence; however, complete removal of soft tissue to closely examine the skeletal elements of these individuals is not common. The decomposition process can mask injuries and impair examination of the skeleton. The case presented by the authors illustrates how complete removal of soft tissue from individuals who have undergone advanced decomposition is necessary to identify all fractures of the skeletal elements. Although removal of the soft tissue from all decomposed remains is not possible, this case shows how carefully the choice of whether to deflesh these remains should be made.

Understanding patterns of trauma is important to determining cause and manner of death. A thorough evaluation of taphonomy, trauma, and bone fracture mechanisms is necessary to reconstruct the circumstances of the death. This study examines the skeletal trauma caused by boat propeller strikes in terms of wound characteristics and location based on three cases from Rhode Island. These case studies review the traumatic characteristics caused by propeller injuries and highlight the anatomic regions most likely to sustain skeletal trauma. With this information, investigators may be able to identify propeller trauma even in severely decomposed remains. The discussion of boat propeller trauma also raises issues regarding how forensic anthropologists and forensic pathologists classify trauma (specifically blunt force vs. sharp) and highlights semantic issues arising in trauma classification. The study also discusses why these propeller cases should be classified as blunt trauma rather than sharp or chop/hack trauma. Ultimately, the authors urge consistency and communication between pathologist and forensic anthropologists performing trauma analyses.

Using simulation, the steady state performance and transient behavior of starved extrusion screws are described. At steady state the filled length of the extruder is controlled by the relative resistance of the screw and die to flow, the flow index of the extrudate, and the feed rate to the extruder. For transient situations, small variations in the composition or feed rate of the material being extruded can significantly alter the extruder's output and filled length. Because of the broader residence time distribution of a twin screw extruder compared to a single screw extruder, the magnitude of the transient effects are seen to be smaller for twin screw extruders. The predicted output transients for extruders operated in the starved condition are of significantly lower magnitude than that for extruders operated in a filled condition. The implications of these effects on the design and operation of extrusion systems are discussed.

A computer simulation illustrating the possibility of extrudate moisture control via feedback of die pressure is described. the simulation of a controller, utilizing dead-time compensation, illustrates the advantages of such a control strategy. the sensitivity of the dead-time compensating controller performance to errors in parameter estimation is examined and discussed. This type of predictive control is found to provide a stable control strategy even with very large modeling errors. Such a control system is readily implemented with a microprocessor.