Irreversible and reversible modes of operation of deterministic ratchets

We discuss a problem of optimization of the energetic efficiency of a simple rocked ratchet. We concentrate on a low-temperature case in which the particle's motion in a ratchet potential is deterministic. We show that the energetic efficiency of a ratchet working adiabatically is bounded from above by a value depending on the form of ratchet potential. The ratchets with strongly asymmetric potentials can achieve ideal efficiency of unity without approaching reversibility. On the other hand we show that for any form of the ratchet potential a set of time-protocols of the outer force exist under which the operation is reversible and the ideal value of efficiency is also achieved. The mode of operation of the ratchet is still quasistatic but not adiabatic. The high values of efficiency can be preserved even under elevated temperatures

Single Low-Dose Lipopolysaccharide Preconditioning: Neuroprotective Against Axonal Injury and Modulates Glial Cells

AIM: Over 7 million traumatic brain injuries (TBI) are reported each year in the United States. However, treatments and neuroprotection following TBI are limited because secondary injury cascades are poorly understood. Lipopolysaccharide (LPS) administration before controlled cortical impact can contribute to neuroprotection. However, the underlying mechanisms and whether LPS preconditioning confers neuroprotection against closed-head injuries remains unclear. METHODS: The authors hypothesized that preconditioning with a low dose of LPS (0.2 mg/kg) would regulate glial reactivity and protect against diffuse axonal injury induced by weight drop. LPS was administered 7 days prior to TBI. LPS administration reduced locomotion, which recovered completely by time of injury. RESULTS: LPS preconditioning significantly reduced the post-injury gliosis response near the corpus callosum, possibly by downregulating the oncostatin M receptor. These novel findings demonstrate a protective role of LPS preconditioning against diffuse axonal injury. LPS preconditioning successfully prevented neurodegeneration near the corpus callosum, as measured by fluorojade B. CONCLUSION: Further work is required to elucidate whether LPS preconditioning confers long-term protection against behavioral deficits and to elucidate the biochemical mechanisms responsible for LPS-induced neuroprotective effects

Extension of a Multiscale Particle Scheme to Near-Equilibrium Viscous Flows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76880/1/AIAA-40262-641.pd

Sesamol: a Treatment for Diabetes-Associated Blood-Brain Barrier Dysfunction

Diabetes is a long-standing disease that leads to secondary complications of capillaries such as retinopathy, nephropathy and neuropathy. Emerging evidence suggests that diabetes may also affect the cerebromicrovasculature, the blood-brain barrier (BBB), and lead to changes in the brain that affect cognition and mood. Therefore, it is important to identify natural compounds that may have therapeutic benefit for reducing BBB dysfunction and improve patient quality of life. Preclinical evidence suggests that sesamol, a natural antioxidant in sesame seed oil, could have therapeutic benefit for treating BBB dysfunction during diabetes. Similarly, paroxetine, which shares a methylenedioxy moiety with sesamol shows clinical benefit for treating neuropathic pain associated with diabetes. This review emphasizes BBB dysfunction as a treatable secondary complication associated with diabetes and examines the evidence for the use of natural compounds like sesamol or existing therapies like paroxetine to help restore BBB function

Sesamol: a Treatment for Diabetes-Associated Blood-Brain Barrier Dysfunction

Abstract Diabetes is a long-standing disease that leads to secondary complications of capillaries such as retinopathy, nephropathy and neuropathy. Emerging evidence suggests that diabetes may also affect the cerebromicrovasculature, the blood-brain barrier (BBB), and lead to changes in the brain that affect cognition and mood. Therefore, it is important to identify natural compounds that may have therapeutic benefit for reducing BBB dysfunction and improve patient quality of life. Preclinical evidence suggests that sesamol, a natural antioxidant in sesame seed oil, could have therapeutic benefit for treating BBB dysfunction during diabetes. Similarly, paroxetine, which shares a methylenedioxy moiety with sesamol shows clinical benefit for treating neuropathic pain associated with diabetes. This review emphasizes BBB dysfunction as a treatable secondary complication associated with diabetes and examines the evidence for the use of natural compounds like sesamol or existing therapies like paroxetine to help restore BBB function