Functionally Graded Media

The notions of uniformity and homogeneity of elastic materials are reviewed in terms of Lie groupoids and frame bundles. This framework is also extended to consider the case Functionally Graded Media, which allows us to obtain some homogeneity conditions.Comment: 20 pages, 5 figure

Implementation and Effects of LDC and MDC in Kentucky Districts

This brief summarizes early evidence on the success of two tools Kentucky districts have used to support their teachers' transition to these more demanding goals: Literacy Design Collaborative (LDC) and Math Design Collaborative (MDC). With support from the Bill and Melinda Gates Foundation, LDC and MDC tools have been designed and implemented to embody the key shifts in teaching and learning that the new standards demand. By implementing the tools, teachers then engage in new pedagogy and address relevant learning goals of the Kentucky Core Academic Standards

Kinematic quantities of finite elastic and plastic deformation

Kinematic quantities for finite elastic and plastic deformations are defined via an approach that does not rely on auxiliary elements like reference frame and reference configuration, and that gives account of the inertial-noninertial aspects explicitly. These features are achieved by working on Galilean spacetime directly. The quantity expressing elastic deformations is introduced according to its expected role: to measure how different the current metric is from the relaxed/stressless metric. Further, the plastic kinematic quantity is the change rate of the stressless metric. The properties of both are analyzed, and their relationship to frequently used elastic and plastic kinematic quantities is discussed. One important result is that no objective elastic or plastic quantities can be defined from deformation gradient.Comment: v5: minor changes, one section moved to an Appendix, 26 pages, 2 figure

Myocardial first-pass perfusion cardiovascular magnetic resonance: history, theory, and current state of the art

In less than two decades, first-pass perfusion cardiovascular magnetic resonance (CMR) has undergone a wide range of changes with the development and availability of improved hardware, software, and contrast agents, in concert with a better understanding of the mechanisms of contrast enhancement. The following review provides a perspective of the historical development of first-pass CMR, the developments in pulse sequence design and contrast agents, the relevant animal models used in early preclinical studies, the mechanism of artifacts, the differences between 1.5T and 3T scanning, and the relevant clinical applications and protocols. This comprehensive overview includes a summary of the past clinical performance of first-pass perfusion CMR and current clinical applications using state-of-the-art methodologies

Successful Xenografts of Second Trimester Human Fetal Brain and Retinal Tissue in the Anterior Chamber of the Eye of Adult Immunosuppressed Rats

Successful xenografting of first trimester human fetal CNS tissue and retina has been reported in the literature. We wished to test the feasibility ofusing the anterior chamber ofthe rat eye to support the development of more mature human fetal xenografts. Here we report on the successful outcome of human brain and retinal transplants. Adult host rats immunosuppressed with cyclosporin A accepted these xenografts and supported their further development. Periodic examination of the host eyes using a direct ophthalmoscope or an ophthalmic slit lamp permitted direct visual monitoring of the health and growth of the transplants. Histologically it was possible to identify neuronal, macroglial, and microglial (macrophage) cell types within the grafts. Mitotic activity and histogenetic differentiation took place. Blood vessels filled with hematic cells were commonly present within the grafts. The walls of these vessels prevented the leakageofhorseradish peroxidase, suggesting the presence of a functional brain-blood barrier in the graft. These results indicate that it is possible to use a small animal model to study normal and pathological phenomena oniate fetal human neural tissues. Our group has already taken advantage of the model to achieve HIV infectivity offetal human brain outside the human body

Environmental enrichment as a therapy for autism: A clinical trial replication and extension.

Based on work done in animal models showing that autism-like symptoms are ameliorated following exposure to an enriched sensorimotor environment, we attempted to develop a comparable therapy for children with autism. In an initial randomized controlled trial, children with autism who received sensorimotor enrichment at home for six months had significant improvements in both their cognitive ability and the severity of their autism symptoms (Woo & Leon, 2013). We now report the outcomes of a similar randomized controlled trial in which children with autism, aged 3-6 years old, were randomly assigned to groups that received either daily sensorimotor enrichment, administered by their parents, along with standard care, or they received standard care alone. After six months, enriched children showed statistically significant gains in their IQ scores, a decline in their atypical sensory responses, and an improvement in their receptive language performance, compared to controls. Furthermore, after six months of enrichment therapy, 21% of the children who initially had been given an autism classification, using the Autism Diagnostic Observation Schedule, improved to the point that, although they remained on the autism spectrum, they no longer met the criteria for classic autism. None of the standard care controls reached an equivalent level of improvement. Finally, the outcome measures for children who received only a subset of sensory stimuli were similar to those receiving the full complement of enrichment exercises. Sensorimotor enrichment therapy therefore appears to be a cost-effective means of treating a range of symptoms for children with autism

The prevalence of wholly attributable alcohol conditions in the United Kingdom hospital system: a systematic review, meta-analysis and meta-regression.

BACKGROUND AND AIMS: The prevalence of alcohol-related conditions is often reported as higher in hospital in-patients compared with the general population. However, formal prevalence estimates are commonly derived from small studies which report highly varied results. This systematic review and meta-analysis, within the UK hospital system, aimed to estimate the pooled prevalence of the 26 ICD-10 conditions that are wholly attributable to alcohol in in-patient settings. METHODS: We searched Medline, Embase, PsychINFO and CENTRAL from database inception until 1 May 2018. We included studies of any design that reported the prevalence of one of 26 wholly attributable alcohol conditions defined by the ICD-10. Studies were required to be conducted in one or more of the constituent nations of the United Kingdom and in an in-patient setting (general wards, intensive care units, accident and emergency departments or mental health in-patient units). Estimates were pooled using random-effects meta-analysis, and meta-regression tested study and patient factors contributing to variation. Quality was assessed using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework. RESULTS: A total of 124 studies were included, reporting on a total of 1 657 614 patients. The majority of studies reported on harmful use of alcohol and alcohol dependence, for which the pooled prevalence was 19.76% [95% confidence interval (CI) = 15.61-24.26%] and 10.25% (95% CI = 7.06-13.96%), respectively. Mean patient age and type of in-patient setting were identified as the main sources of variation in prevalence estimates, but not date of data collection. Both estimates were deemed very low quality according to GRADE. CONCLUSIONS: An estimated one in five patients in the UK hospital system use alcohol harmfully, and one in 10 are alcohol-dependent

Differences in coronary flow and myocardial metabolism at rest and during pacing between patients with obstructive and patients with nonobstructive hypertrophic cardiomyopathy

Fifty patients with hypertrophic cardiomyopathy underwent invasive study of coronary and myocardial hemodynamics in the basal state and during the stress of pacing. The 23 patients with basal obstruction (average left ventricular outflow gradient, 77 ± 33 mm Hg; left ventricular systolic pressure, 196 ± 33 mm Hg, mean ± 1 SD) had significantly lower coronary resistance (0.85 ± 0.18 versus 1.32 ± 0.44 mm Hg min/ml, p < 0.001) and higher basal coronary flow (106 ± 20 versus 80 ± 25 ml/min, p < 0.001) in the anterior left ventricle, associated with higher regional myocardial oxygen consumption (12.4 ± 3.6 versus 8.9 ± 3.3 ml oxygen/min, p < 0.001) compared with the 27 patients without obstruction (mean left ventricular systolic pressure 134 ± 18 mm Hg, p < 0.001).Myocardial oxygen consumption and coronary blood flow were also significantly higher at paced heart rates of 100 and 130 beats/min (the anginal threshold for 41 of the 50 patients) in patients with obstruction compared with those without. In patients with obstruction, transmural coronary flow reserve was exhausted at a heart rate of 130 beats/min; higher heart rates resulted in more severe metabolic evidence of ischemia with all patients experiencing chest pain, associated with an actual increase in coronary resistance. Patients without obstruction also demonstrated evidence of ischemia at heart rates of 130 and 150 beats/min, with 25 of 27 patients experiencing chest pain. In this group, myocardial ischemia occurred at significantly lower coronary flow, higher coronary resistance and lower myocardial oxygen consumption, suggesting more severely impaired flow delivery in this group compared with those with obstruction. Abnormalities in myocardial oxygen extraction and marked elevation in filling pressures during stress were noted in both groups.Thus, obstruction to left ventricular outflow is associated with high left ventricular systolic pressure and oxygen consumption and therefore has important pathogenetic importance to the precipitation of ischemia in patients with hypertrophic cardiomyopathy. Patients without obstruction may have greater impairment in coronary flow delivery during stress

Catheter-based autologous bone marrow myocardial injection in no-option patients with advanced coronary artery disease A feasibility study

AbstractObjectivesWe conducted a pilot study to evaluate the feasibility of transendocardial delivery of autologous bone marrow (ABM) strategy in patients with severe symptomatic chronic myocardial ischemia not amenable to conventional revascularization.BackgroundTransendocardial injection of ABM cells appears to enhance perfusion of ischemic porcine myocardium.MethodsTen patients underwent transendocardial injection of freshly aspirated and filtered unfractionated ABM using left ventricular electromechanical guidance. Twelve injections of 0.2 ml each were successfully delivered into ischemic noninfarcted myocardium pre-identified by single-photon emission computed tomography perfusion imaging.ResultsAutologous bone marrow injection was successful in all patients and was associated with no serious adverse effects; in particular, there was no arrhythmia, evidence of infection, myocardial inflammation, or increased scar formation. Two patients were readmitted for recurrent chest pain. At three months, Canadian Cardiovascular Society angina score significantly improved (3.1 ± 0.3 vs. 2.0 ± 0.94, p = 0.001), as well as stress-induced ischemia occurring within the injected territories (2.1 ± 0.8 vs. 1.6 ± 0.8, p < 0.001). Treadmill exercise duration, available in nine patients, increased, but the change was not significant (391 ± 155 vs. 485 ± 198, p = 0.11).ConclusionsThis study provides preliminary clinical data indicating feasibility of catheter-based transendocardial delivery of ABM to ischemic myocardium