LM cathode thruster system Quarterly progress report, 4 Jan. 1969 - 4 Apr. 1970

Development of 20 cm liquid metal cathode thruster syste

Queen discrimination by honeybee (Apis mellifera L) workers

A simple new technique for testing worker honeybees' ability to distinguish between honeybee queens is presented. Two queens were caged separately with groups of young sibling workers which were the daughters of another queen. The cages were exposed to the same environmental odours for 10 days. When placed in the test apparatus and given a choice of both queens, workers segregated towards the queen with which they had been caged. This provides further evidence that the distinctive odour of an individual queen is probably partly inherited and is learned by workers. The nature and functioning of queen odours are discussed

Magnetic flux flow and superconductor stabilization Quarterly report, 1 Jan. - 31 Mar. 1968

Magnetic flux flow and stability of superconducting niobium titanium strip

Mechatronic Camera Operator: Final Design Report

A mechatronic system is designed, constructed, and tested to aid filmmakers in the movement and control of a video camera. The system design allows for 6-DOF camera movement (movement in all three spatial directions, pan, tilt, and roll). The system is controlled by a human operator, using an implementation of a gamepad controller, and the system is battery-powered; the theoretical range of the system is therefore limited only by the onboard battery power, and the operator’s ability to keep within cord-length of the system as it moves. A misallocation of time resources resulted in an incomplete physical design, but preliminary testing indicates that the design is sound, and that mechanical specifications are sufficiently robust for a working final system. Further time and resources would be used to complete physical construction and electronic implementation, and to implement a feedback system to allow for closed-loop actuator control and the function of repeatable motio

Theme Overview: Agriculture and Water Quality in the Cornbelt: Overview of Issues and Approaches

Resource /Energy Economics and Policy, Q25,

Estrogens as neuroprotectants: Estrogenic actions in the context of cognitive aging and brain injury

There is ample empirical evidence to support the notion that the biological impacts of estrogen extend beyond the gonads to other bodily systems, including the brain and behavior. Converging preclinical findings have indicated a neuroprotective role for estrogen in a variety of experimental models of cognitive function and brain insult. However, the surprising null or even detrimental findings of several large clinical trials evaluating the ability of estrogen-containing hormone treatments to protect against age-related brain changes and insults, including cognitive aging and brain injury, led to hesitation by both clinicians and patients in the use of exogenous estrogenic treatments for nervous system outcomes. That estrogen-containing therapies are used by tens of millions of women for a variety of health-related applications across the lifespan has made identifying conditions under which benefits with estrogen treatment will be realized an important public health issue. Here we provide a summary of the biological actions of estrogen and estrogen-containing formulations in the context of aging, cognition, stroke, and traumatic brain injury. We have devoted special attention to highlighting the notion that estrogen appears to be a conditional neuroprotectant whose efficacy is modulated by several interacting factors. By developing criteria standards for desired beneficial peripheral and neuroprotective outcomes among unique patient populations, we can optimize estrogen treatments for attenuating the consequences of, and perhaps even preventing, cognitive aging and brain injury

Extracellular Vesicles Secreted in Response to Cytokine Exposure Increase Mitochondrial Oxygen Consumption in Recipient Cells

Extracellular vesicles (EVs) are small, membrane-bound nanoparticles released from most, if not all cells, and can carry functionally active cargo (proteins, nucleic acids) which can be taken up by neighboring cells and mediate physiologically relevant effects. In this capacity, EVs are being regarded as novel cell-to-cell communicators, which may play important roles in the progression of neurodegenerative diseases, like Alzheimer’s disease (AD). Aside from the canonical physical hallmarks of this disease [amyloid β (Aβ) plaques, neurofibrillary tangles, and widespread cell death], AD is characterized by chronic neuroinflammation and mitochondrial dysfunction. In the current study, we sought to better understand the role of tumor necrosis factor-alpha (TNF-α), known to be involved in inflammation, in mediating alterations in mitochondrial function and EV secretion. Using an immortalized hippocampal cell line, we observed significant reductions in several parameters of mitochondrial oxygen consumption after a 24-h exposure period to TNF-α. In addition, after TNF-α exposure we also observed significant upregulation of two microRNAs (miRNAs; miR-34a and miR-146a) associated with mitochondrial dysfunction in secreted EVs. Despite this, when naïve cells are exposed to EVs isolated from TNF-α treated cells, mitochondrial respiration, proton leak, and reactive oxygen species (ROS) production are all significantly increased. Collectively these data indicate that a potent proinflammatory cytokine, TNF-α, induces significant mitochondrial dysfunction in a neuronal cell type, in part via the secretion of EVs, which significantly alter mitochondrial activity in recipient cells

Two-dimensional Navier--Stokes simulation of deformation and break up of liquid patches

The large deformations and break up of circular 2D liquid patches in a high Reynolds number (Re=1000) gas flow are investigated numerically. The 2D, plane flow Navier--Stokes equations are directly solved with explicit tracking of the interface between the two phases and a new algorithm for surface tension. The numerical method is able to pursue the simulation beyond the breaking or coalescence of droplets. The simulations are able to unveil the intriguing details of the non-linear interplay between the deforming droplets and the vortical structures in the droplet's wake.Comment: 13 pages including 4 postscript figures; Revised version as resubmitted to PRL. Title has change