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Numerous observers and critics of higher education, including some policymakers, have suggested that hiring and maintaining faculty on tenure lines is a primary source of inefficiency in colleges and universities. These "disrupters" argue that reducing commitments to tenure will lead to cost savings and more effective adaptations to changing markets for various degrees. Does increasing hiring of "contingent" (non-tenure-line) faculty indeed bring financial benefits? In this analysis, we use longitudinal data to examine that hypothesis in financially stressed public master's and doctoral institutions over the period 2003 to 2014. The analysis provides no support for the hypothesis. The implications of these results for research and practice are discussed. [ABSTRACT FROM AUTHOR]

Background: College-completion policies dominate state higher education policy agendas. Yet we know little about how policy actors make decisions--and what sources of evidence they use--within this policy domain. Focus of Study: This study explores the use of evidence in college-completion policymaking in depth, focusing on Texas. In addition to exploring policymakers' use of different types of information, this study examines the role played by intermediaries. Research Design: We employed a qualitative case study design drawing on interviews with 32 policy actors engaged in college-completion policy in Texas. Our analysis consisted of both deductive coding (based on our a priori coding scheme) and inductive coding (based on emerging themes) to arrive at our four major findings. Findings/Results: The analysis revealed four primary findings. The first theme suggests an insular culture of college-completion policymaking: Policymakers at various levels preferred Texas-based data and rejected the notion that external groups contributed to setting the college completion agenda in Texas. Second, business groups and a business ethos permeated college-completion policymaking in Texas. Third, research evidence was seldom employed in this policy process, partly because policymakers prefer concise and timely information. Finally, the study uncovered a new tactic for supplying research employed by certain intermediaries: punchy messaging, which was effective at garnering attention but also yielded unintended consequences. Conclusions/Recommendations: Overwhelmingly, higher education policy actors tended to prefer Texas-based data. Respondents cited three major reasons for this preference: the high quality of the state higher education coordinating board's data, Texas's unique demographics, and the accessibility of statewide data. These findings reflect the mediating role that is played not only by state structural characteristics, but also by culture. Perceptions of Texas's distinctive inward-looking nature permeated our interviews and set the stage for the role that intermediaries played in the state and the preferences for information. Intermediaries wishing to inform college-completion policy activity at the state level should consider the uniqueness of the state context in supplying information. For states that are more insular, like Texas, working through internal (in-state) intermediaries may be an effective strategy. In light of our findings of preferred types of information, those intending to influence policymaking should consider making information--especially research evidence--concise and easily accessible and establish relationships with policymakers and their staff members. [ABSTRACT FROM AUTHOR]

Objective: Recent guidelines advocate for ongoing balance testing in the assessment ofmanagement of concussion injuries. This study sought to determine whether the Balance Tracking System (BTrackS) provides stable balance results over repeated administration and, thus, is a reliable tool for concussion management. Design: Repeated measures and test--retest reliability. Setting: University Biomechanics Laboratory. Participants: Random sample of 20 healthy young adults. Interventions: Force plate balance testing using BTrackS on days 1, 3, 8, and 15. Main Outcome Measures: Practiceinduced changes in the average center of pressure excursion over 4 repeated administrations of the BTrackS Balance Test (BBT). Test--retest reliability of center of pressure excursion from day 1 to day 15. Results: No significant practice-induced balance differences were found across testing days (P . 0.4), and test--retest reliability of the BBT was excellent from day 1 to day 15 (R 0.92). Conclusions: These findings indicate that the BBT does not elicit a practice effect over repeat administrations. BTrackS provides excellent reliability and objectivity, which can increase clinician accuracy when monitoring sportrelated concussions. [ABSTRACT FROM AUTHOR]

As many national commissions and observers have noted, the past forty years have brought unprecedented declines in humanities enrollments and programs in U.S. higher education. These changes are particularly striking in the iconic academic heart of the enterprise, the four-year college sector, where many institutions have diversified curricular offerings well beyond their historic roots in the liberal arts. Colleges have significantly varied, however, in the extent of their retreat from the traditional core curriculum. What factors, then, are associated with maintaining earlier established academic norms in this organizational field? This analysis of four-year colleges' humanities degree production investigates several propositions, concluding that deeper institutionalization and stronger financial resources have been especially important in constraining schools' retreat from the humanities over recent decades. Examination of time-based interaction effects suggests notable evolution in the role of religious affiliation and gender in humanities degree production over the period. Implications of the findings for research and policy are considered. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the socioeconomic diversity in selective private colleges. Topics include the role of role of selective private colleges in developing the educational and socioeconomic outcomes among students of lower socioeconomic status (SES), the tuition gap between public and private institutions, and the enrollment patterns in U.S. postsecondary education.

As economic competition becomes more global and knowledge-based, US states have independently pursued initiatives in research and development (R&D) and science and technology (S&T). Policy efforts often entwine government, universities, and industry, aiming to stimulate socially optimal levels of innovation and economic growth. Partnerships in this arena are well documented, but few studies foreground first-person accounts of policy dynamics. Through comparative case study of Georgia, Missouri, and Texas, we present perspectives of government, university, and industry leaders, who form and negotiate boundaries and roles for collaboration. We find that (1) S&T competition has been distinct from national initiatives and more domestic than global; (2) the three states feature similar policies but have evolved ‘new economy’ approaches idiosyncratically; and (3) universities in these states have driven endeavours, evincing specific industry/corporate perspectives. Themes suggest competition – not collaboration – within a national-innovation system and intriguing yet challenging opportunities for academic leaders and managers. [ABSTRACT FROM AUTHOR]

The article presents information on research and development in the U.S. as of 2013, focusing on state government recruiting programs for scientists to become university faculty members and on the potential economic implications of the programs at the state and national levels. The authors look at a study on eminent scholars (ES) programs, college-level science and technology research, and the Georgia Research Alliance (GRA). The article also discusses the use of governing boards and coordinating boards in terms of state governance of public higher education.

Background/Context: Every state in the nation has legal requirements, state "sunshine laws," to ensure accountability and fairness in institutions receiving state funds and operating under state authority. These laws have come to significantly influence the ways in which the business of higher education is conducted. Purpose/Objective/Research Question/Focus of Study: This reflective essay provides perspective on laws mandating openness in higher education. It describes differences in the laws across states, reports select findings from a study on the impacts of the laws on public colleges and universities, and examines some of the implications of the contemporary debate over access to information on public campuses. Research Design: The article builds on a previous field study of state sunshine laws that included site visits to six states and interviews with nearly 100 officials with firsthand perspective on the laws. Conclusions/Recommendations: Information resources have expanded tremendously, yet the nature and extent of their availability to the larger public remain in question. How can deeply held values of openness and access be accommodated productively to privacy and security concerns, with minimal threats to each? The article seeks to contribute to a growing body of literature on information policy and its uses in society--in this case, how the public information laws of state governments influence the climate of data access and decision-making in public higher education. [ABSTRACT FROM AUTHOR]

Background: The use of an interference fit wedged bone plug to provide fixation in the tibial tunnel when using bone-patellar tendon-bone autograft for anterior cruciate ligament reconstruction offers many theoretic advantages including the potential to offer a more economical and biological alternative to screw fixation. This technique has not been subjected to biomechanical testing. We hypothesised that a wedged bone plug fixation technique provides equivalent tensile load to failure as titanium interference screw fixation. Methods: In a controlled laboratory setting, anterior cruciate ligament reconstruction was performed in 36 bovine knees using bone-patella-bone autograft. In 20 knees tibial fixation relied upon a standard cuboid bone block and interference screw. In eight knees a wedge shaped bone block with an 11 mm by 10 mm base without a screw was used. In a further eight knees a similar wedge with a 13 mm by 10 mm base was used. Each specimen used a standard 10 mm tibial tunnel. The reconstructions were tested biomechanically in a physiological environment using an Instron machine to compare ultimate failure loads and modes of failure. Results: Statistical analysis revealed no significant difference between wedge fixation and screw fixation (p = 0.16), or between individual groups (interference screw versus 11 mm versus 13 mm wedge fixation) (P = 0.35). Conclusions: Tibial tunnel fixation using an impacted wedge shaped bone block in anterior cruciate ligament reconstruction has comparable ultimate tensile strength to titanium interference screw fixation. [ABSTRACT FROM AUTHOR]

The article discusses political aspects of state funding for higher education in the U.S. The authors comment on declines in state aid to higher education due to decreased taxes, increases in healthcare costs and decreases in federal grants to states and suggest that higher education is considered a low priority in state budgets. A longitudinal study was conducted focusing on how factors such as demographics, legislative and gubernatorial control by Republicans and Democrats, state economics, interest groups, political term limits and citizen ideology affect higher education funding by states. The study suggested that political professionalism and lobbying resulted in increased higher education funding while Republican political control led to reductions in funding.

We present two- and three-dimensional simulations involving Richtmyer–Meshkov and Rayleigh-Taylor instabilities run with the adaptive mesh refinement code, flash. Variations in the rate of mixing layer growth due to dimensionality, perturbation modes, and simulation resolution are explored. These simulations are designed for detailed comparisons with experiments run on the Omega laser to gain understanding of the mixing processes and to prepare for validation of the Flash code. [ABSTRACT FROM AUTHOR]

The article presents a study of transparency in government, specifically, of state sunshine laws as they relate to higher education. The article seeks to determine how stakeholders perceive open-meetings and records laws and their impact on higher education. Contemporary sunshine laws are considered. The study covers the sunshine laws of six state university systems. Twelve findings are discussed, including the importance and universal valuing of openness in higher education, the institutionalization of sunshine laws in higher education governance, and stakeholders' definition of "public good" as it related to higher education. The authors also provide policy recommendations.

Implementing an incentives-based budget system at a large public research university significantly redirected internal funds while producing notable organizational and financial surprises. For example, units did not increase their "hoarding" of students, contrary to some expectations. The findings point to several issues for further analysis and research. [ABSTRACT FROM PUBLISHER]

An ovine model of anterior cruciate ligament reconstruction was utilized to evaluate the biomechanical and histological response of a polylactic acid tibial fixation staple (Gunze Ltd., Japan/Zimmer, Japan). This was performed in a comparison with metallic staples, currently utilized for this procedure. The prosthesis consisted of autograft combined with a Leeds–Keio (L–K) ligament. Early post-operative mobilization was followed by retrieval of specimens at 6, 12 and 24 weeks post-reconstruction. Evaluation of the mechanical characteristics of the graft reconstructions (tensile strength) showed no significant differences (P>0.05) between the staple types for each time period. The histological response to the polylactic acid staple was minimal over the time period studied, with no adverse tissue reactions observed. The mode of reconstruction failure was observed to change with time (P<0.05) presumably as the graft characteristics alter. Overall the absorbable staples performed at a comparable level with the metallic staples within the scope of the study. [Copyright &y& Elsevier]

An ovine model of anterior cruciate ligament reconstruction was utilized to evaluate the biomechanical and histological response of a polylactic acid tibial fixation staple (Gunze Ltd., Japan/Zimmer, Japan). This was performed in a comparison with metallic staples, currently utilized for this procedure. The prosthesis consisted of autograft combined with a Leeds-Keio (L-K) ligament. Early post-operative mobilization was followed by retrieval of specimens at 6, 12 and 24 weeks post-reconstruction. Evaluation of the mechanical characteristics of the graft reconstructions (tensile strength) showed no significant differences (P>0.05) between the staple types for each time period. The histological response to the polylactic acid staple was minimal over the time period studied, with no adverse tissue reactions observed. The mode of reconstruction failure was observed to change with time (P<0.05) presumably as the graft characteristics alter. Overall the absorbable staples performed at a comparable level with the metallic staples within the scope of the study. [ABSTRACT FROM AUTHOR]

Discusses the politics of higher education. Historical and contemporary perspectives on the political involvements of higher education; Introduction to articles on the politics of higher education.

Because the academic department is the foundational unit of U.S. universities, conflict in that setting is both theoretically and practically important. This analysis focuses on divisiveness in votes for promotion and tenure in departments at a large research university. The findings suggest that the departments most likely to experience very split voting patterns are those with larger instructional loads for faculty, low levels of internal curricular specialization, and “soft” disciplinary paradigms. The implications of these results for research and practice are discussed. [ABSTRACT FROM AUTHOR]

Increasingly, state governments are implementing policies and practices that either directly or indirectly focus on college students' learning outcomes. This article examines the emerging context for these policies and practices, then explores various state efforts that potentially influence undergraduate outcomes. Among the policies and practices considered are several relating to funding, including standardized state-funding formulas, incentive-based funding systems, targeted budget allocations, faculty salary policies, tuition policies for public institutions, and taxation policies and practices. Also considered are state policies and practices relating directly to academic programming, staffing, and accountability, including institutional mission differentiation, developmental education policies, transfer and articulation policies and practices, state-mandated admissions standards, and polices and practices relating to distance learning. The article concludes with strategies to enhance policy effectiveness in this arena. [ABSTRACT FROM AUTHOR]

Objective. To determine the hydration-over-time behaviour of ovine intervertebral discs and intact joints in a saline bath at body temperature and the effect this has on their stiffness compared to air at ambient temperature.Design. The hydration-over-time behaviour and stiffness of the ovine functional spinal unit and disc were quantified.Background. The fluid content of an intervertebral disc is not constant but varies with external load and load history. The stiffness of ovine functional spinal units in a hydrated environment and how this compares to testing in air have not been quantified.Methods. Intervertebral discs and functional spinal units were weighed and soaked in a saline water bath at 37 °C and reweighed each hour for 6 h. They were then allowed to stand in air at room temperature while the time to return to initial weight was recorded. Functional spinal units were randomly assigned to two groups. Axial compression, flexion, extension, lateral bending and axial torsion tests were performed on both the intact functional spinal unit and isolated disc. Group 1 was tested in air then in a saline water bath at 37 °C with the testing order reversed for Group 2.Results. Hydration of the disc reached a plateau after an average 3–4 h of soaking with the largest increase seen in the first hour. Four hours, standing in air at room temperature, was required to return specimens to their initial weight. The functional spinal unit stiffness was significantly lower for those specimens tested in the bath compared to air.Conclusions. Ovine intervertebral discs show similar hydration-over-time behaviour when compared to human discs. Stiffnesses in different modes of loading were significantly different when tested in a hydrated environment compared with the standard method of testing in air.Relevance It has been shown that there are biomechanical and biochemical similarities between sheep and human intervertebral discs. Despite these similarities, no studies have looked at how ovine intervertebral discs behave over time in a hydrated environment. In humans, hydration levels are an important aspect of intervertebral disc degeneration. There is also a relationship between decreased hydration levels and increased stiffness. This study demonstrates the similarities between human and ovine hydration-over-time behaviour. The importance of intervertebral disc hydration and its effects on stiffness under different modes of loading were also demonstrated and have not been previously shown using the ovine model. In this context, the results from this study provide further support for the use of the ovine model. [Copyright &y& Elsevier]

A single, complete, ovine knee was imaged using conventional MRI then dissected allowing comprehensive dimensional measurement of the intra-articular structures. A three-dimensional (3-D) computer model of the knee was generated from the MR sections. Thirty-two individual structural measures were recorded from the image output for which there was an available surgical measure for direct comparison. The results of Pearson''s correlation testing show a rounded score of 1.00, suggesting an exceptional linear correlation between direct anatomical measurement and the 3-D image output. Further analysis of the data revealed an average error of measurement of 0.2 mm across the 32 measures. The findings of this preliminary study suggest that 3-D reconstruction from MR data may be an appropriate, and accurate, means for making dimensional measurements of the bony and soft tissue structures of the ovine knee. It is unlikely that the measurement error would be of any great clinical significance. There is evidence in the literature to suggest that an ovine knee may be considered an acceptable model for substitution for the human knee in diagnostic assessment studies. Therefore, such findings may be considered clinically relevant in the field of human knee assessment. [Copyright &y& Elsevier]

Reports on an investigation of differences and similarities across the 50 states in the United States in terms of approaches to the pricing and discounting, via student aid, of undergraduate education. Philosophical origins of public tuition and aid policies; Theoretical framework; Per-capita state student aid; State tuition pricing policies.

Presents information on an article which looked at state policy in relation to public research universities. Perception on curtailing the enrollment of out of state students in public colleges and universities; Discussion on the uncertainties regarding the future of higher education.

Reports on a study about the post school attainment effects resulting from student participation in typing and keyboarding coursework as part of secondary general education. The effects of keyboarding on employment, earnings, further educational attainment, and related equity and cost-effectiveness issues were examined. Significant positive effects; Data used; Details.

Discusses theories and research evidence on organizational change in colleges and universities in the United States. Higher education's balancing of openness to change; Faculty's freedom to structure themselves and act as they choose; Taking a political perspective on educational change.

Examines the emergence and subsequent five-year history of `environmental scanning' at a large research university. Approach to effective decision making; Systematic understanding of the external environment; Difficulties in institutionalizing scanning.

Focuses on Minnesota's experiment with high tuition/high aid approach to student support. Background on the state's policy on tuition and student aid; Features of Minnesota's approach to postsecondary finance; Policy lessons from the Minnesota experience.

Two rationales have been used to support governmental funding of postsecondary vocational education: an efficiency rationale and an equity rationale. Research on the effects of this public investment, and thus on the defensibility of these rationales, has often been hampered by inadequate data and other limitations. The analysis presented in this article used the nationally representative High School and Beyond data set to investigate the distinctive role of postsecondary vocational education in affecting the earnings, employment, and socioeconomic mobility of the nation's high school graduates of 1980. The results suggest that postsecondary vocational education does, indeed, have significant positive effects on individual economic outcomes, but those effects are not found among all who are targeted by the equity rationale. In particular, men from lower socioeconomic backgrounds do not appear to benefit appreciably. The analysis, however, provides striking support for the equity rationale as it applies to women. [ABSTRACT FROM AUTHOR]

The article examines the equality of opportunity to postsecondary education. It focuses on the relationships between high school graduates' personal like ability, achievements, expectations, etc., and the nature of the postsecondary institutions they attend. Demographic, socioeconomic, and legislative trends have lowered the barriers to access to college to such an extent that virtually any high school graduate can now obtain entry into some part of the postsecondary system. The nature of individuals' experi- ences while in college may influence important outcomes other than the eventual attainment of status and income, such as religious and racial-ethnic tolerance, general contentedness, and participation in civic activities. From a theoretical perspective, the effects of the educational system on both the alleviation and reproduction of social inequalities and the changes in those relative roles over time are subjects of continuing interest and appreciable dispute. Ascriptive factors help channel the development of youths' ability and achievement and are arguably more influential in the formation of educational aspirations than are the ongoing, putatively universalistic cues that students receive regarding their academic talents.

In response to goals of expanding access as well as public pressure to leverage substantial endowment resources toward increasing affordability, numerous elite colleges have enacted policies aimed at improving access and affordability by replacing student loans with grants in financial aid packages. No-loan policies, however, differ in the extent to which they expand affordability: Some policies offer a universal discount by replacing loans with grants for all aid-eligible students, while others offer narrowly targeted discounts to students based on income, Pell Grant eligibility status, or another means-tested threshold. We leveraged newly available Equality of Opportunity Project Mobility Report Card data and a difference-in-differences design using unweighted and weighted comparison groups to examine the relationship between adoption of universal and targeted no-loan policies and economic diversity at elite colleges. We found that colleges offering universal discounts experienced increased enrollment among middle-class students. Our study indicates universal no-loan policies represent one strategy to increase access and affordability for the middle-class in the elite reaches of higher education. The study also, however, raises questions about the policies' effectiveness in addressing access for low-income students and efficiency in targeting aid. [ABSTRACT FROM AUTHOR]

Galaxy clusters, the most massive collapsed structures, have been routinely used to determine cosmological parameters. When using clusters for cosmology, the crucial assumption is that they are relaxed. However, subarcminute resolution Sunyaev-Zel'dovich (SZ) effect images compared with high-resolution X-ray images of some clusters show significant offsets between the two peaks. We have carried out self-consistent N-body/hydrodynamical simulations of merging galaxy clusters using FLASH to study these offsets quantitatively. We have found that significant displacements result between the SZ and X-ray peaks for large relative velocities for all masses used in our simulations as long as the impact parameters were about 100-250 kpc. Our results suggest that the SZ peak coincides with the peak in the pressure times the line-of-sight characteristic length and not the pressure maximum (as it would for clusters in equilibrium). The peak in the X-ray emission, as expected, coincides with the density maximum of the main cluster. As a consequence, the morphology of the SZ signal, and therefore the offset between the SZ and X-ray peaks, change with viewing angle. As an application, we compare the morphologies of our simulated images to observed SZ and X-ray images and mass surface densities derived from weak-lensing observations of the merging galaxy cluster CL0152-1357, we find that a large relative velocity of 4800 km s–1 is necessary to explain the observations. We conclude that an analysis of the morphologies of multi-frequency observations of merging clusters can be used to put meaningful constraints on the initial parameters of the progenitors. [ABSTRACT FROM AUTHOR]

Stem cell research has emerged as a state-level science and technology policy issue in recent years in the USA, with some states supporting research in the field and others choosing to restrict it. In this paper, we systematically explore the factors that are associated with US states’ adoptions of both supportive and restrictive stem cell policies. Our analysis identifies several factors, including partisan politics, existing morality policies, the strength of a state’s scientific community and the policy environment in neighboring states, which influence the adoption of state stem cell policies. Our paper aims to advance the science and technology policy literature by providing insight into the factors that push states to adopt science policies when economic development goals conflict with ethical concerns. [ABSTRACT FROM AUTHOR]

Football teams draw the largest crowds of any American collegiate sport, and with them, both positive and negative attention for colleges and universities. Nearly 50 colleges have added the sport recently, but little research has examined the institutional effects of adding a team. Some of these institutions are regional research universities adding the sport as part of broad plans to transform campus identities, while at smaller public and private institutions, adding a football team (with approximately 100 members) appears to be an attempt to boost racial diversity and the number of male students. This study uses difference-in-difference models to find that adding a football team appears to have a significant, but short-term, effect on enrollment and tuition revenue. The long-term effects of adding the sport do not appear to be statistically significant. This raises questions about the costs and benefits of adding football at a time when higher education faces significant challenges attracting students. [ABSTRACT FROM AUTHOR]

The article examines reforms in state governance of public institutions of higher education in the U.S. between 1985 and 2000. The authors discuss research by public administration scholars and those who research the organization of public higher education, and they investigate why states chose the governance arrangements they did and why some states did not enact reforms. They examine economic and political factors affecting governance reforms and discuss how problems internal to higher education influence decisions. They examine a counter-conventional account of governance reform, which they call the "political instability hypothesis, investigate nine hypotheses of comparative state politics and higher education, and use event history analysis to examine social aspects of the study.

To examine the similarities and differences in cognitive function between three predominantly subcortical dementing disorders associated with parkinsonism we compared the profiles of cognitive performance in 39 patients with Progressive Supranuclear Palsy (PSP), 26 patients with Multiple System Atrophy (MSA) and 25 with Corticobasal Degeneration (CBD) with those of 30 patients with classic cortical dementia, Alzheimer’s Disease (AD), using two different cognitive screening tests: Dementia Rating Scale (DRS) and Addenbrooke’s Cognitive Examination (ACE). The cognitive profile on ACE and DRS subtests distinguished subcortical diseases from each other as well as from AD. All parkinsonian syndromes were characterized by a disproportionate impairment in verbal fluency, particularly letter fluency. The three diseases differed, however, in the degree of language, memory and visuospatial impairment. We conclude that similarities, as well as differences, between PSP, MSA and CBD can be detected using a brief, clinically applicable cognitive screening test. The pattern of cognitive impairment is likely to reflect a different distribution of pathology, in particular a higher degree of cortical involvement in PSP and CBD. [ABSTRACT FROM AUTHOR]

Focuses on a study which compared the torsional strengths of bioabsorbable screws for anterior cruciate ligament reconstruction. Materials and methods; Modes of failure among bioabsorbable screws; Effect of screw diameter on torsional strengths.

Background: Fractures of the femoral neck already represent a major public health problem in Australia. This situation is set to worsen as the population ages. The present study estimates the number of patients over 50 years of age with femoral neck fractures that is expected to impact on the South Australian healthcare service into the next century. Methods: Population projections from the Australian Bureau of Statistics 1996 census were combined with age- and gender-specific incidence rates for fractures of the femoral neck for persons over the age of 50 in South Australia. Projections for the expected number of hip fractures in this State were then calculated. Results: Assuming there are no changes in the age- and gender-specific incidence of fracture rates, the number of fractures in South Australia is estimated to increase by approximately 66% by the year 2021 and 190% by 2051. Conclusion: Based on the population projections and the assumption that conditions contributing to hip fractures remain constant, the number of fractured neck of femurs will increase in far greater proportion than the overall population in the next century. The results of the present study indicate the serious implications for the South Australian healthcare system if there is no reduction in incidence rates. [ABSTRACT FROM AUTHOR]

Objectives: Visuospatial deficits have been occasionally reported but never systematically studied in atypical parkinsonian syndromes. The interpretation of existing studies is complicated by the possible influence of motor and frontal executive deficits. Moreover, no attempt has been made to distinguish visuoperceptual from visuospatial tasks. The aim of the present study was to assess visuoperceptual and visuospatial abilities in three atypical parkinsonian syndromes while minimising the influence of confounding variables. Methods: Twenty patients with multiple system atrophy (MSA), 43 with progressive supranuclear palsy (PSP), and 25 with corticobasal degeneration (CBD) as well as 30 healthy age matched controls were examined with the Visual Object and Space Perception Battery (VOSP). Results: Visuospatial functions were intact in MSA patients. PSP patients showed mild deficits related to general cognitive decline and the severity of oculomotor symptoms. The CBD group showed the most pronounced deficits, with spatial tasks more impaired than object based tasks. Performance on object based, but not spatial, tasks was related to general cognitive status. The extent of the visuospatial impairment could not be predicted from disease duration or severity. Conclusion: Visuospatial Functions are not consistently impaired in atypical parkinsonian syndromes. The degree and pattern of impairment varies across the diseases, suggesting that the observed deficits could have a different neural basis in each condition. The distinction between the object based ("ventral stream") and the space oriented ("dorsal stream") processing might be useful in the interpretation of visuospatial deficits in parkinsonian syndromes, especially in CBD. [ABSTRACT FROM AUTHOR]

Background: Rare hematopoietic stem cell populations are responsible for the transplantation engraftment process. Umbilical cord blood (UCB) is usually processed to the total nucleated cell (TNC), but not to the mononuclear cell (MNC) fraction. TNC counts are used to determine UCB unit storage, release for transplantation and correlation with time to engraftment. However, the TNC fraction contains varying concentrations of red blood cells, granulocytes, platelets and other cells that dilute and mask the stem cells from being detected. This does not allow the quality and potency of the stem cells to be reliably measured. Methods: 63 UCB segments and 10 UCB units plus segments were analyzed for the response of both primitive lympho-hematopoietic and primitive hematopoietic stem cells in both the TNC and MNC fractions. The samples were analyzed using a highly sensitive, standardized and validated adenosine triphosphate (ATP) bioluminescence stem cell proliferation assay verified against the colony-forming unit (CFU) assay. Dye exclusion and metabolic viability were also determined. Results: Regardless of whether the cells were derived from a segment or unit, the TNC fraction always produced a significantly lower and more variable stem cell response than that derived from the MNC fraction. Routine dye exclusion cell viability did not correspond with metabolic viability and stem cell response. Paired UCB segments produced highly variable results, and the UCB segment did not produce similar results to the unit. Discussion: The TNC fraction underestimates the ability and capacity of the stem cells in both the UCB segment and unit and therefore provides an erroneous interpretation of the of the results. Dye exclusion viability can result in false positive values, when in fact the stem cells may be dead or incapable of proliferation. The difference in response between the segment and unit calls into question the ability to use the segment as a representative sample of the UCB unit. It is apparent that present UCB processing and testing methods are inadequate to properly determine the quality and potency of the unit for release and use in a patient. [ABSTRACT FROM AUTHOR]

Abstract: Over 95% of imports entering the United States from outside North America arrive by sea at 329 ports of entry. These imports are packaged in more than 11 million cargo containers. Radiation portals monitors routinely scan cargo containers leaving port on specially-designed trucks. To accelerate the process, some commercial entities have placed detection systems on the spreader-bar cranes (SBCs) used to offload. Little is known about the radiation background profiles of systems operating on these cranes. To better understand the operational characteristics of these radiation detection systems; a research team from Texas A&M University (TAMU) mounted three thallium-doped sodium iodide [NaI(Tl)] detectors on an SBC at the Domestic Nuclear Detection Office's (DNDO) test track facility at the Port of Tacoma (PoT). These detectors were used to monitor background radiation levels and continuously recorded data during crane operations using a custom-built software package. Count rates and spectral data were recorded for various crane heights over both land and water. The results of this research created a background profile in which count rate was heavily dependent on position demonstrating how detector readings changed in the operational environment. [Copyright &y& Elsevier]

Abstract: Background: A gamma irradiation dose of 15kGy has been shown to adequately sterilise allograft bone, commonly used in femoral impaction bone grafting to treat bone loss at revision hip replacement, without significantly affecting its mechanical properties. The objective of this study was to evaluate whether use of 15kGy irradiated bone affects the initial mechanical stability of the femoral stem prosthesis, as determined by micromotion in a comprehensive testing apparatus, in a clinically relevant time zero in vitro model of revision hip replacement. Methods: Morselised ovine bone was nonirradiated (control), or irradiated at 15kGy or 60kGy. For each dose, six ovine femurs were implanted with a cemented polished taper stem following femoral impaction bone grafting. Using testing apparatus that reproduces stem loading, stems were cyclically loaded and triaxial micromotion of the stem relative to the bone was measured at the proximal and distal stem regions using non-contact laser transducers and linear variable differential transformers. Findings: There were no significant differences in proximal or distal stem micromotion between groups for all directions (p≤0.80), apart for significantly greater distal stem medial–lateral micromotion in the 60kGy group compared to the 15kGy group (P =0.03), and near-significance in the anterior–posterior direction (P =0.08, power=0.85). Interpretation: Using a clinically relevant model and loading apparatus, irradiation of bone at 15kGy does not affect initial femoral stem stability following femoral impaction bone grafting. [Copyright &y& Elsevier]

Internal fixation of fractures often requires the tightening of bone screws to stabilise fragments. Inadequate application of torque can leave the fracture unstable, while over-tightening results in the stripping of the thread and loss of fixation. The optimal amount of screw torque is specific to each application and in practice is difficult to attain due to the wide variability in bone properties including bone density. The aim of the research presented in this paper is to investigate the relationships between motor torque and screw compression during powered screw insertion, and to evaluate whether the torque during insertion can be used to predict the ultimate failure torque of the bone. A custom test rig was designed and built for bone screw experiments. By inserting cancellous bone screws into synthetic, ovine and human bone specimens, it was established that variations related to bone density could be automatically detected through the effects of the bone on the rotational characteristics of the screw. The torque measured during screw insertion was found to be directly related to bone density and can be used, on its own, as a good predictor of ultimate failure torque of the bone. [ABSTRACT FROM AUTHOR]

Background: In order to confer optimal strength and stiffness to the graft in Anterior Cruciate Ligament (ACL) reconstruction, the maintenance of equal strand tension prior to fixation, is desired; positioning of the tensioning device can significantly affect strand tension This study aimed to determine the effect of tensioning device malpositioning on individual strand tension in simulated cadaveric ACL reconstructions. Methods: Twenty cadaveric specimens, comprising bovine tibia and tendon harvested from sheep, were used to simulate ACL reconstruction with a looped four-strand tendon graft. A proprietary tensioning device was used to tension the graft during tibial component fixation with graft tension recorded using load cells. The effects of the tensioning device at extreme angles, and in various locking states, was evaluated. Results: Strand tension varied significantly when the tensioning device was held at extreme angles (p < 0.001) or in 'locked' configurations of the tensioning device (p < 0.046). Tendon position also produced significant effects (p < 0.016) on the resultant strand tension. Conclusion: An even distribution of tension among individual graft strands is obtained by maintaining the tensioning device in an unlocked state, aligned with the longitudinal axis of the tibial tunnel. If the maintenance of equal strand tension during tibial fixation of grafts is important, close attention must be paid to positioning of the tensioning device in order to optimize the resultant graft tension and, by implication, the strength and stiffness of the graft and ultimately, surgical outcome. [ABSTRACT FROM AUTHOR]