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Software Development for Laser Engineered Net Shaping
Laser Engineered Net Shaping, also known as LENSTM, is an advanced manufacturing technique used to
fabricate near-net shaped, fully dense metal components directly from computer solid models without the
use oftraditional machining processes. The LENSTM process uses a high powered laser to create a molten
pool into which powdered metal is injected and solidified. Like many SFF techniques, LENSTM parts are
made through a layer additive process. In the current system, for any given layer, the laser is held
stationary, while the part and its associated substrate is moved, allowing for the each layer's geometry to
be formed. Individual layers are generated by tracing out the desired border, followed by filling in the
remaining volume. Recent research into LENSTM has highlighted the sensitivity ofthe processes to
multiple software controllable parameters such as substrate travel velocity, border representation, and fill
patterns. This research is aimed at determining optimal border outlines and fill patterns for LENSTM and
at developing the associated software necessary for automating the creation ofthe desired motion control.Mechanical Engineerin
A thermalized ion explosion model for high energy sputtering and track registration
A velocity spectrum of neutral sputtered particles as well as a low resolution mass spectrum of sputtered molecular ions was measured for 4.74 MeV F-19(+2) incident of UF4. The velocity spectrum is dramatically different from spectra taken with low energy (keV) bombarding ions, and is shown to be consistent with a hot plasma of atoms in thermal equilibrium inside the target. A thermalized ion explosion model is proposed for high energy sputtering which is expected to describe track formation in dielectric materials. The model is shown to be consistent with the observed total sputtering yield and the dependence of the yield on the primary ionization rate of the incident ion
DNA in the Courtroom: The 21st Century Begins
DNA is one of the most significant discoveries in the field of forensic evidence yet it remains underutilized in the courtroom setting. This article provides an introduction to the scientific principles, structure and composition of DNA in an effort to make DNA more accessible to the judicial process
Care, control and the electroconvulsive therapy (ECT) ritual: Making sense of polarised patient narratives
Despite evidence of short-term effectiveness of ECT (electroconvulsive therapy), both positive and negative patient reports are common. However, research examining these polarized accounts has not adequately elucidated why such divergences occur. We thus sought to examine opposing patient narratives to better understand underlying meanings. Eighteen interviews were conducted with UK-based people who had experienced the treatment. Our analysis revealed that the quality of relations with staff, ECT artefacts (e.g. the ECT suite), and perceived outcomes all play a role in divergent accounts. Positive reflections on ECT emerged alongside narratives of trust in staff, comfort with ECT, and perception of sufficient personal control. Conversely, where negative evaluations of ECT predominated, there was anger associated with a lack of control, and a belief that ECT made little sense, and was linked to past abuses and/or the unacceptability of side effects. We discuss the implications of our findings for professionals
A Meta-Analysis of Crew Resource Management/Incident Command Systems Implementation Studies in the Fire and Emergency Services
The presentation will summarize a meta-analysis of studies on Crew Resource Management/Incident Command System implementation in the fire and emergency services. The need for using participative leadership tools such as CRM evolved from an NTSB recommendation that followed United Airlines Flight 173 crash in 1978. NASA, civilian and military aviation communities implemented Crew Resource Management (CRM) training to improve decisionmaking during flight operations. Maintenance Resource Management (MRM) was a variant of CRM and first appeared in a Federal Aviation Administration circular in 2000. CRM was adopted by the medical community in the 1990s, specifically in the surgical and nursing areas, to prevent untoward outcomes (including infections). Since the mid-1990s, fire and emergency services organizations began using CRM and Incident Command Systems training to reduce human error in firefighting and prehospital care. This research focuses on fire and emergency services studies to determine if CRM/Incident Command Systems training impact attitude and performance in a meaningful way. Meta-analysis statistical procedures will identify differences and levels of heterogeneity between these studies, where possible, to support findings and recommendations for future research.
Keywords: crew resource management, incident command systems, fire, emergency services, maintenance resource management, participative leadershi
Absence of halfmetallicity in defect-free Cr, Mn-delta-doped Digital Magnetic Heterostructures
We present results of a combined density functional and many-body
calculations for the electronic and magnetic properties of the defect-free
digital ferromagnetic heterostructures obtained by doping GaAs with Cr and Mn.
While local density approximation/(+U) predicts half-metallicity in these
defect-free delta-doped heterostructures, we demonstrate that local many-body
correlations captured by Dynamical Mean Field Theory induce within the minority
spin channel non-quasiparticle states just above . As a consequence of the
existence of these many-body states the half-metallic gap is closed and the
carriers spin polarization is significantly reduced. Below the Fermi level the
minority spin highest valence states are found to localize more on the GaAs
layers being independent of the type of electronic correlations considered.
Thus, our results confirm the confinement of carriers in these delta-doped
heterostructures, having a spin-polarization that follow a different
temperature dependence than magnetization. We suggest that polarized
hot-electron photoluminescence experiments might bring evidence for the
existence of many-body states within the minority spin channel and their finite
temperature behavior.Comment: 10 pages 8 figures, submitted to PR
Bullying at the Fire Station? Perceptions Based on Gender, Race and Sexual Orientation
Discrimination and strained co-worker relationships based on gender, race or sexual orientation are forms of bullying in the workplace. This research examined firefighter perceptions with regard to bullying. The web based survey was distributed through the National Fire Academy Training, Resources and Data Exchange Network, (TRADENET). Findings from 113 surveys indicated that most firefighters did not perceive bullying issues were pervasive in the fire service. However, there were large differences in perception between female and male firefighters. Significantly more female firefighters indicated they were treated differently due to gender, felt their supervisors did not address complaints concerning gender or sexual orientation, had ill-fitting uniforms or equipment, and believed promotions were not decided upon fairly. Recommendations included continuing to assess female and minority perceptions with regard to perceived discrimination. Additionally, fire service leadership should identify best practices in leadership and firefighter training to effectively address fair treatment for all firefighters
A Meta-Analysis of Crew Resource Management/Incident Command Systems Implementation Studies in the Fire and Emergency Services
The presentation will summarize a meta-analysis of studies on Crew Resource Management/Incident Command System implementation in the fire and emergency services. The need for using participative leadership tools such as CRM evolved from an NTSB recommendation that followed United Airlines Flight 173 crash in 1978. NASA, civilian and military aviation communities implemented Crew Resource Management (CRM) training to improve decisionmaking during flight operations. Maintenance Resource Management (MRM) was a variant of CRM and first appeared in a Federal Aviation Administration circular in 2000. CRM was adopted by the medical community in the 1990s, specifically in the surgical and nursing areas, to prevent untoward outcomes (including infections). Since the mid-1990s, fire and emergency services organizations began using CRM and Incident Command Systems training to reduce human error in firefighting and prehospital care. This research focuses on fire and emergency services studies to determine if CRM/Incident Command Systems training impact attitude and performance in a meaningful way. Meta-analysis statistical procedures will identify differences and levels of heterogeneity between these studies, where possible, to support findings and recommendations for future research.
Keywords: crew resource management, incident command systems, fire, emergency services, maintenance resource management, participative leadershi
A common founding clone with TP53 and PTEN mutations gives rise to a concurrent germ cell tumor and acute megakaryoblastic leukemia
We report the findings from a patient who presented with a concurrent mediastinal germ cell tumor (GCT) and acute myeloid leukemia (AML). Bone marrow pathology was consistent with a diagnosis of acute megakaryoblastic leukemia (AML M7), and biopsy of an anterior mediastinal mass was consistent with a nonseminomatous GCT. Prior studies have described associations between hematological malignancies, including AML M7 and nonseminomatous GCTs, and it was recently suggested that a common founding clone initiated both cancers. We performed enhanced exome sequencing on the GCT and the AML M7 from our patient to define the clonal relationship between the two cancers. We found that both samples contained somatic mutations in PTEN (C136R missense) and TP53 (R213 frameshift). The mutations in PTEN and TP53 were present at ∼100% variant allele frequency (VAF) in both tumors. In addition, we detected and validated five other shared somatic mutations. The copy-number analysis of the AML exome data revealed an amplification of Chromosome 12p. We also identified a heterozygous germline variant in FANCA (S858R), which is known to be associated with Fanconi anemia but is of uncertain significance here. In summary, our data not only support a common founding clone for these cancers but also suggest that a specific set of distinct genomic alterations (in PTEN and TP53) underlies the rare association between GCT and AML. This association is likely linked to the treatment resistance and extremely poor outcome of these patients. We cannot resolve the clonal evolution of these tumors given limitations of our data
Cyclosporine metabolite concentrations in the blood of liver, heart, kidney, and bone marrow transplant patients.
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