Constitutive relation development through the FIRE test

The importance of well-developed constitutive models for predicting deformation behavior of materials at high strain rates cannot be overstated. The study and development of these constitutive models is pertinent to several fields, yet the test methods utilized to probe this high strain-rate realm are limited in both number and standardization. In an effort to augment current high rate tests, new technologies have been leveraged to revive an old, under-utilized test method - the axisymmetric expanding ring. The combination of Photon Doppler Velocimetry (PDV) and one of several ring launch techniques allows the successful testing and instrumentation of samples loaded in tension without wave effects at strain rates exceeding 10^4 s^-1. Design and construction of the embodiment of this test at OSU, dubbed the Fully Instrumented Ring Expansion (FIRE) system, will be discussed. The key difficulties to implementation of the test are examined, along with our efforts to overcome them and preliminary results

The effect of fibre cell remodelling on the power and optical quality of the lens.

Vertebrate eye lenses are uniquely adapted to form a refractive index gradient (GRIN) for improved acuity, and to grow slowly in size despite constant cell proliferation. The mechanisms behind these adaptations remain poorly understood. We hypothesize that cell compaction contributes to both. To test this notion, we examined the relationship between lens size and shape, refractive characteristics and the cross-sectional areas of constituent fibre cells in mice of different ages. We developed a block-face imaging method to visualize cellular cross sections and found that the cross-sectional areas of fibre cells rose and then decreased over time, with the most significant reduction occurring in denucleating cells in the adult lens cortex, followed by cells in the embryonic nucleus. These findings help reconcile differences between the predictions of lens growth models and empirical data. Biomechanical simulations suggested that compressive forces generated from continuous deposition of fibre cells could contribute to cellular compaction. However, optical measurements revealed that the GRIN did not mirror the pattern of cellular compaction, implying that compaction alone cannot account for GRIN formation and that additional mechanisms are likely to be involved

Conversion From Tacrolimus to Belatacept to Prevent the Progression of Chronic Kidney Disease in Pancreas Transplantation: Case Report of Two Patients

Belatacept is a novel immunosuppressive agent that may be used as an alternative to calcineurin inhibitors (CNI) in immunosuppression (IS) regimens. We report two cases of pancreas transplant that were switched from tacrolimus (TAC) to belatacept. Case 1: 38‐year‐old female with pancreas transplant alone maintained on TAC‐based IS regimen whose serum creatinine (SCr) slowly deteriorated from 0.6 mg/dL at baseline to 2.2 mg/dL, 16 months posttransplant. A native kidney biopsy performed showed CNI toxicity. The patient was started on belatacept and TAC was eliminated. Case 2: 49‐year‐old female with simultaneous pancreas–kidney transplant, maintained on TAC‐based regimen where the SCr worsened over an initial 3‐month period from a baseline of 1.0 to 3.0 mg/dL. Belatacept was started and TAC was lowered. Due to persistent graft dysfunction and kidney transplant biopsy still showing changes consistent with CNI toxicity, the TAC was then discontinued. At >1 year postbelatacept and off TAC follow‐up, kidney function as measured by SCr remains stable at 1.0 ± 0.2 mg/dL in both recipients. Neither patient developed rejection following the switch, and pancreas allograft function remains stable in both recipients

Mii and MiiBump: Supporting pregnant women to continue or commence an active lifestyle

The purpose of this study was to investigate how women perceive exercising during pregnancy and whether existing technologies could be used to support active behaviours. Information for pregnant women who wish to continue or start exercising is limited and not readily offered. With the ever growing capability and accessibility to technologies research is warranted to investigate whether it could be used to help support exercising during pregnancy. An interpretative phenomenological approach was used to conduct in-depth interviews with five women, via purposive sampling. The data revealed that the participants perceived a number of barriers to active behaviours, such as the lack of a pregnant buddy with which to exercise. A lack of provided information was evident with the women claiming to have sought appropriate information themselves. Findings highlighted the potential for existing technologies to be utilised in order to support and enhance exercise behaviours during pregnancy

Macroscopic Equations of Motion for Two Phase Flow in Porous Media

The established macroscopic equations of motion for two phase immiscible displacement in porous media are known to be physically incomplete because they do not contain the surface tension and surface areas governing capillary phenomena. Therefore a more general system of macroscopic equations is derived here which incorporates the spatiotemporal variation of interfacial energies. These equations are based on the theory of mixtures in macroscopic continuum mechanics. They include wetting phenomena through surface tensions instead of the traditional use of capillary pressure functions. Relative permeabilities can be identified in this approach which exhibit a complex dependence on the state variables. A capillary pressure function can be identified in equilibrium which shows the qualitative saturation dependence known from experiment. In addition the new equations allow to describe the spatiotemporal changes of residual saturations during immiscible displacement.Comment: 15 pages, Phys. Rev. E (1998), in prin

The Effects of Body Tempering on Force Production, Flexibility and Muscle Soreness in Collegiate Football Athletes

There has been limited research to explore the use of body tempering and when the use of this modality would be most appropriate. This study aimed to determine if a body tempering intervention would be appropriate pre-exercise by examining its effects on perceived soreness, range of motion (ROM), and force production compared to an intervention of traditional stretching. The subjects for this study were ten Division 1 (D1) football linemen from Sacred Heart University (Age: 19.9 ± 1.5 years, body mass: 130.9 ± 12.0 kg, height: 188.4 ± 5.1 cm, training age: 8.0 ± 3.5 years). Subjects participated in three sessions with the first session being baseline testing. The second and third sessions involved the participants being randomized to receive either the body tempering or stretching intervention for the second session and then receiving the other intervention the final week. Soreness using a visual analog scale (VAS), ROM, counter movement jump (CMJ) peak force and jump height, static jump (SJ) peak force and jump height, and isometric mid-thigh pull max force production were assessed. The results of the study concluded that body tempering does not have a negative effect on muscle performance but did practically reduce perceived muscle soreness. Since body tempering is effective at reducing soreness in athletes, it can be recommended for athletes as part of their pre-exercise warmup without negatively effecting isometric or dynamic force production

Comparing Mean & Peak Barbell Velocity During Traditional and Accentuated Eccentric Loaded Back Squats

MV: There were statistically significant main effects present for both condition (p = 0.002; g = 0.10-0.23) and load (p \u3c 0.001; g = 0.95-3.93). However, the condition x time interaction effect was not statistically significant (p = 0.259). • PV: There were statistically significant main effects present for both condition (p = 0.016; g = 0.11-0.23) and load (p \u3c 0.001; g = 0.42-1.6), but there was no statistically significant condition x time interaction effect (p = 0.101). • Post hoc analysis indicated that there was a significant difference between MV (p = 0.006) and PV (p = 0.032) between the traditional and 100% AEL conditions. • Moderate effect sizes were found with MV between the traditional and 100% AEL conditions at both 70% CON (g = 0.55) and 80% CON (g = 0.70). • No practically significant differences were found for PV

What Do Bureaucrats Do? The Effects of Performance Standards and Bureaucratic Preferences on Acceptance into the JTPA Program

Bureaucratic performance standards are featured in many proposals to increase efficiency in government. These standards reward bureaucrats on the basis of measured outcomes. The performance standards system created under the Job Training Partnership Act (JTPA) of 1982 is often cited as a successful prototype. Under the JTPA system, local training centers receive monetary rewards based on the employment levels and wage rates attained by their trainees upon completion of the program. Critics of the JTPA performance standards system argue that it creates an incentive for program managers to encourage case workers to `cream-skim' the most employable applicants into the program. We examine this issue by analyzing the determinants of acceptance into JTPA among applicants at a training center for which we have data on everyone who applied over a two year period. We find that case workers prefer to accept the least employable applicants, rather than the most employable as suggested by the cream-skimming story. This evidence indicates that concerns about cream-skimming in JTPA may be exaggerated. Instead, the performance standards system may operate as a countervailing force against the preferences of case workers. Using experimental data from the recent National JTPA Study, we also determine whether or not case workers accept those applicants with higher expected gains from the program. Our evidence only weakly supports this hypothesis.

Secondary students' values and perceptions of science-related careers: responses to vignette-based scenarios

There has been concern about the attractiveness of science-based careers to many adolescent learners, and it has been suggested that school science may not always recognise or engage personal values that are important to young people in making life choices. The present study discusses interview comments made by upper secondary level students in England when 15 young people were asked to give their personal responses to brief vignettes describing scientific careers. Using an interview-about-scenarios approach, the students were asked about whether they would feel comfortable working in the scientific careers represented. The career areas were purposefully selected because they might be considered to potentially raise issues in relation to personal values or commitments that some students might hold. A range of student perceptions relating to the mooted careers were elicited (positive, negative and indifferent), but all of the participants raised issues that impacted on the acceptability or attractiveness of at least one of the mooted scientific careers, in terms of aspects of their own personal beliefs and values systems. It is recommended that teachers and career advisors should be aware of the range of value-related considerations that influence student views of science-related careers and should consider exploring aspects of science-based careers that link to values commonly shared by young people. This exploratory study also offers indications for directions for further research exploring how learners' value systems impact upon their perceptions of science and scientific work