Crystal structure, thermodynamics, magnetics and disorder properties of Be-Fe-Al intermetallics

The elastic and magnetic properties, thermodynamical stability, deviation from stoichiometry and order/disorder transformations of phases that are relevant to Be alloys were investigated using density functional theory simulations coupled with phonon density of states calculations to capture temperature effects. A novel structure and composition were identified for the Be-Fe binary {\epsilon} phase. In absence of Al, FeBe_5 is predicted to form at equilibrium above ~ 1250 K, while the {\epsilon} phase is stable only below ~ 1650 K, and FeBe_2 is stable at all temperatures below melting. Small additions of Al are found to stabilise FeBe_5 over FeBe_2 and {\epsilon}, while at high Al content, AlFeBe_4 is predicted to form. Deviations from stoichiometric compositions are also considered and found to be important in the case of FeBe_5 and {\epsilon}. The propensity for disordered vs ordered structures is also important for AlFeBe_4 (which exhibits complete Al-Fe disordered at all temperatures) and FeBe_5 (which exhibits an order-disorder transition at ~ 950 K).Comment: 14 pages, 10 figures, accepted for publication in J. Alloy Compd. on 14 March 201

A Review of Temporomandibular Disorder and an Analysis of Mandibular Motion

This study quantified mandibular motion of asymptomatic subjects upon jaw opening and closing. Five males, mean age of 28 years, agreed to participate; they showed no sign or symptom of temporomandibular disorder (TMD) on clinical examination or by anamnestic history. Mandibular motion for each subject was measured with a tracking system and software utilizing the Screw Displacement Axis (SDA), which is a mathematical approach to analyzing and quantifying the movement of an object in three dimensions. Rotation and translation were calculated, as well as two- and three-dimensional charting of condylar path and sagittal condylar intercepts. Furthermore, analyses examined error propagation, change in error amplitude with varying test conditions, and a comparison between theoretical and experimental data. The mean maximum roation around the screw displacement axes was 25.0o (sd=4.0o). Mean translation along the screw displacement axes was 2.3 mm (sd = 0.68 mm). The SDA intersection plots showed that the paths of motion for all subjects were posterior and inferior to the candyle. During opening, paths start nearer to the condyle and travel inferiorly and anteriorly. Jaw closing followed the reverse path (superior and posterior) with the final position approximating the area of the initial axis. Mean SDA intercepts with the sagittal plane of the condyle were positioned posterior and inferior of the selected center of the condyle. SDA position and orientation parameters were inversely related to the rotational increment. As rotational increments approached 5o, there was little change in the uncertainty values, indicating that data should be processed at increments of at least 4o to 5o. Coordinate data obtained with the tracking systemn displayed an error that was not present when the targets were stationary, nor did its amplitude change with a change in velocity. These observations led to the idea that the error associated with the tracking system relied purely on target position. The only way to counter this system error was to raise the rotational increments in data processing and find an area in the sensor\u27s viewing field that produces the least error. The closest the targets could be brought to the camera while maintaining a viewing area large enough to test jaw motion was in the range of 150-200 mm from the senor. The experimental data obtained from the SDA intercepts at 10oiterations showed a path similar to theoretical expectations. The screw displacement axis method does have limitations. If only translational motion occurs, the SDA is undefinded. The SDA method is also very prone to measurement error. At low rotational increments, large error of the SDA parameters can be encourntered due to small measurement inaccuracies. However, small rotational increments are necessary to reliably approximate the continuous movement through a series of finite calculations. A balance is threfore required between these two opposing error sources

Motivations, Barriers, and Impact of Continuing Judicial Education: A Survey of U.S. Judges

The journey to the bench is unique for every judge. For most, however, a position on the bench is preceded by law school, the bar exam, and a career as an attorney. Through these experiences, judges are expected to become knowledgeable about the responsibilities and duties that come with their new role. In fact, common-law judiciaries, such as the United States, are built on the assumption that legal practice is the best preparation for being a judge.1 Still, many judges might feel as if they are not fully prepared. Unlike judges in civil-law countries, who undertake specialized coursework in judicial studies from the earliest stages of their careers, judges in the United States typically “[take] the oath, [step] onto the bench, and [proceed] to fill the judicial role as if born in the robe.”2 As one judge put it, “[B]ecoming a federal judge is like being thrown into the water and being told to swim.”

Order, disorder and stability in Be intermetallics for fusion applications

Be intermetallics are a promising family of materials for the first wall and neutron multiplying applications in future nuclear fusion reactors, owing to their low atomic number, still high beryllium content but improved thermo-mechanical properties over pure beryllium. Due to the difficulties of working with Be, however, they are often poorly characterized. Thus, the crystallography, elastic and magnetic properties, thermodynamical stability, deviation from stoichiometry and order/disorder transformations of intermetallics, which are relevant to Be alloys have been investigated using computer simulation [1,2,3]. These include Be-Fe-Al ternary phases as well as a series of Be-transition metal binaries. Throughout the density functional code CASTEP was employed, coupled with phonon density of states calculations to capture temperature effects. The propensity for intermetallics to act as impurity sinks was also considered. Please click Additional Files below to see the full abstract

Ariel - Volume 8 Number 3

Executive Editor James W. Lockard, Jr. Business Manager Neeraj K. Kanwal University News Richard J . Perry World News Doug Hiller Opinions Elizabeth A. McGuire Features Patrick P. Sokas Sports Desk Shahab S. Minassian Managing Editor Edward H. Jasper Managing Associate Brenda Peterson Photography Editor Robert D. Lehman. Jr. Graphics Christine M. Kuhnl

miR-196b target screen reveals mechanisms maintaining leukemia stemness with therapeutic potential.

We have shown that antagomiR inhibition of miRNA miR-21 and miR-196b activity is sufficient to ablate MLL-AF9 leukemia stem cells (LSC) in vivo. Here, we used an shRNA screening approach to mimic miRNA activity on experimentally verified miR-196b targets to identify functionally important and therapeutically relevant pathways downstream of oncogenic miRNA in MLL-r AML. We found Cdkn1b (p27Kip1) is a direct miR-196b target whose repression enhanced an embryonic stem cell–like signature associated with decreased leukemia latency and increased numbers of leukemia stem cells in vivo. Conversely, elevation of p27Kip1 significantly reduced MLL-r leukemia self-renewal, promoted monocytic differentiation of leukemic blasts, and induced cell death. Antagonism of miR-196b activity or pharmacologic inhibition of the Cks1-Skp2–containing SCF E3-ubiquitin ligase complex increased p27Kip1 and inhibited human AML growth. This work illustrates that understanding oncogenic miRNA target pathways can identify actionable targets in leukemia

Judges and forensic science education: A national survey

In criminal cases, forensic science reports and expert testimony play an increasingly important role in adjudication. More states now follow a federal reliability standard, which calls upon judges to assess the reliability and validity of scientific evidence. Little is known about how judges view their own background in forensic scientific evidence, and what types of specialized training they receive on it. In this study, we surveyed 164 judges from 39 different U.S. states, who attended past trainings at the National Judicial College. We asked these judges about their background in forensic science, their views concerning the reliability of common forensic disciplines, and their needs to better evaluate forensic science evidence. We discovered that judges held views regarding the scientific support for different forensic science disciplines that were fairly consistent with available literature; their error rate estimates were more supported by research than many estimates by laypersons, who often assume forensic methods are nearly infallible. We did not find any association between how judges rate forensic reliability and prior training. We did, however, find that training corresponded with judges’ views that they should, and do in fact, take on a more active gatekeeping role regarding forensics. Regarding the tools judges need to vet forensic experts and properly evaluate forensic science evidence, they reported having very different backgrounds in relevant scientific concepts and having forensic science education needs. Judges reported needs in accessing better material concerning reliability of forensic science methods. These results support new efforts to expand scientific evidence education in the judiciary

An Environmental Science and Engineering Framework for Combating Antimicrobial Resistance

On June 20, 2017, members of the environmental engineering and science (EES) community convened at the Association of Environmental Engineering and Science Professors (AEESP) Biennial Conference for a workshop on antimicrobial resistance. With over 80 registered participants, discussion groups focused on the following topics: risk assessment, monitoring, wastewater treatment, agricultural systems, and synergies. In this study, we summarize the consensus among the workshop participants regarding the role of the EES community in understanding and mitigating the spread of antibiotic resistance via environmental pathways. Environmental scientists and engineers offer a unique and interdisciplinary perspective and expertise needed for engaging with other disciplines such as medicine, agriculture, and public health to effectively address important knowledge gaps with respect to the linkages between human activities, impacts to the environment, and human health risks. Recommendations that propose priorities for research within the EES community, as well as areas where interdisciplinary perspectives are needed, are highlighted. In particular, risk modeling and assessment, monitoring, and mass balance modeling can aid in the identification of “hot spots” for antibiotic resistance evolution and dissemination, and can help identify effective targets for mitigation. Such information will be essential for the development of an informed and effective policy aimed at preserving and protecting the efficacy of antibiotics for future generations