Magnetic recording head and method of making same Patent

Magnetic recording head composed of ferrite core coated with thin film of aluminum-iron-silicon allo

Shuttle payload bay dynamic environments: Summary and conclusion report for STS flights 1-5 and 9

The vibration, acoustic and low frequency loads data from the first 5 shuttle flights are presented. The engineering analysis of that data is also presented. Vibroacoustic data from STS-9 are also presented because they represent the only data taken on a large payload. Payload dynamic environment predictions developed by the participation of various NASA and industrial centers are presented along with a comparison of analytical loads methodology predictions with flight data, including a brief description of the methodologies employed in developing those predictions for payloads. The review of prediction methodologies illustrates how different centers have approached the problems of developing shuttle dynamic environmental predictions and criteria. Ongoing research activities related to the shuttle dynamic environments are also described. Analytical software recently developed for the prediction of payload acoustic and vibration environments are also described

Extended-life magnetic recording heads

Recording head has standard ferrite core directly coated with a thin film of a magnetic alloy composed of aluminum, iron, and silicon. Coated head has a lifespan from five to ten times longer than that of conventional heads and shows superior inductance characteristics and frequency response

Integrated Atom Detector Based on Field Ionization near Carbon Nanotubes

We demonstrate an atom detector based on field ionization and subsequent ion counting. We make use of field enhancement near tips of carbon nanotubes to reach extreme electrostatic field values of up to 9x10^9 V/m, which ionize ground state rubidium atoms. The detector is based on a carpet of multiwall carbon nanotubes grown on a substrate and used for field ionization, and a channel electron multiplier used for ion counting. We measure the field enhancement at the tips of carbon nanotubes by field emission of electrons. We demonstrate the operation of the field ionization detector by counting atoms from a thermal beam of a rubidium dispenser source. By measuring the ionization rate of rubidium as a function of the applied detector voltage we identify the field ionization distance, which is below a few tens of nanometers in front of nanotube tips. We deduce from the experimental data that field ionization of rubidium near nanotube tips takes place on a time scale faster than 10^(-10)s. This property is particularly interesting for the development of fast atom detectors suitable for measuring correlations in ultracold quantum gases. We also describe an application of the detector as partial pressure gauge.Comment: 7 pages, 8 figure

Microsurgical Technique of Simultaneous Pancreas/Kidney Transplantation in the Rat: Clinical Experience and Review of the Literature

Background: For experimental basic research, standardized transplantation models reflecting technical and immunologic aspects are necessary. This article describes an experimental model of combined pancreas/kidney transplantation (PKTx) in detail. Materials and Methods: Donor rats underwent en bloc pancreatectomy and nephrectomy. Revascularization was performed using the aorta with the superior mesenteric artery and the inferior vena cava with the portal vein. Exocrine drainage of the pancreas took place over a segment of the duodenum which was transplanted side-to-side to the jejunum. The kidney vessels were transplanted end-to-side. The ureter was anastomosed by patch technique. Postoperatively, serum parameters were monitored daily. Biopsies for histopathology were taken on days 5, 8 and 12. Results: All 12 recipients survived the combined PKTx without serious surgical complications. One thrombosis of the portal vein led to organ failure. Blood glucose levels were normal by the 3rd postoperative day. The transplanted duodenal segment showed slight villous atrophy, and the kidneys were well perfused without vascular complications. The anastomosis between ureter and bladder was leakproof. Conclusions: Excellent graft function and survival rates can be achieved due to simplified operation technique and short operation time. It may thus have high clinical relevance to immunologic issues within the scope of basic research. Copyright (C) 2009 S. Karger AG, Base

Preferred auditory temporal processing regimes and auditory-motor synchronization

Decoding the rich temporal dynamics of complex sounds such as speech is constrained by the underlying neuronal-processing mechanisms. Oscillatory theories suggest the existence of one optimal perceptual performance regime at auditory stimulation rates in the delta to theta range (< 10 Hz), but reduced performance in the alpha range (10–14 Hz) is controversial. Additionally, the widely discussed motor system contribution to timing remains unclear. We measured rate discrimination thresholds between 4 and 15 Hz, and auditory-motor coupling strength was estimated through a behavioral auditory-motor synchronization task. In a Bayesian model comparison, high auditory-motor synchronizers showed a larger range of constant optimal temporal judgments than low synchronizers, with performance decreasing in the alpha range. This evidence for optimal processing in the theta range is consistent with preferred oscillatory regimes in auditory cortex that compartmentalize stimulus encoding and processing. The findings suggest, remarkably, that increased auditory-motor synchronization might extend such an optimal range towards faster rates

Reproductive Suicide: Similar Mechanisms of Aging in C. elegans and Pacific Salmon

In some species of salmon, reproductive maturity triggers the development of massive pathology resulting from reproductive effort, leading to rapid post-reproductive death. Such reproductive death, which occurs in many semelparous organisms (with a single bout of reproduction), can be prevented by blocking reproductive maturation, and this can increase lifespan dramatically. Reproductive death is often viewed as distinct from senescence in iteroparous organisms (with multiple bouts of reproduction) such as humans. Here we review the evidence that reproductive death occurs in C. elegans and discuss what this means for its use as a model organism to study aging. Inhibiting insulin/IGF-1 signaling and germline removal suppresses reproductive death and greatly extends lifespan in C. elegans, but can also extend lifespan to a small extent in iteroparous organisms. We argue that mechanisms of senescence operative in reproductive death exist in a less catastrophic form in iteroparous organisms, particularly those that involve costly resource reallocation, and exhibit endocrine-regulated plasticity. Thus, mechanisms of senescence in semelparous organisms (including plants) and iteroparous ones form an etiological continuum. Therefore understanding mechanisms of reproductive death in C. elegans can teach us about some mechanisms of senescence that are operative in iteroparous organisms

An electrochemical study of a liquid crystal used in information displays

The operational lifetime of liquid crystal displays were investigated. Electrochemical reaction at the electrodes of the display can cause failure after 2000 to 3000 hours of operation. Studies using cyclic voltametry of electrochemical reactions of N (p-methoxybenzilidene p-butylaniline (MBBA), a nematic liquid crystal were made. These studies indicate the presence of a reversible reduction of MBBA at the cathode, and that the reduction product undergoes a further reaction leading to products which are not reversibly oxidized. It is concluded that the degradation of the liquid crystal in displays can be reduced with a suitable frequency of alternating voltage