Explant Analysis of Total Disc Replacement

Explant analysis of human disc prostheses allow early evaluation of the host response to the prosthesis and the response of the prosthesis from the host. Furthermore, early predictions of failure and wear can be obtained. Thus far, about 2-3% of disc prostheses have been removed. Observed wear patterns are similar to that of appendicular prostheses including abrasions/scratching, burnishing, surface deformation, fatigue, and embedded debris. Chemically the polymeric components have shown little degradation in short-term implantation. In metal on metal prostheses the histologic responses consist of large numbers of metallic particles with occasional macrophages and giant cells. Only rare cases of significant inflammatory response from polymeric debris have been seen

Qualitative Assessment of Risk for Monkeypox Associated with Domestic Trade in Certain Animal Species, United States

TOC summary: The probability of further human infection is low and the risk is further mitigated by rodent import restrictions

Incipient order in the t-J model at high temperatures

We analyze the high-temperature behavior of the susceptibilities towards a number of possible ordered states in the t-J-V model using the high-temperature series expansion. From all diagrams with up to ten edges, reliable results are obtained down to temperatures of order J, or (with some optimism) to J/2. In the unphysical regime, t<J, large superconducting susceptibilities are found, which moreover increase with decreasing temperatures, but for t>J, these susceptibilities are small and decreasing with decreasing temperature; this suggests that the t-J model does not support high-temperature superconductivity. We also find modest evidence of a tendency toward nematic and d-density wave orders. ERRATUM: Due to an error in the calculation, the series for d-wave supeconducting and extended s-wave superconducting orders were incorrect. We recalculate the series and give the replacement figures. In agreement with our earlier findings, we still find no evidence of any strong enhancement of the superconducting susceptibility with decreasing temperature. However, because different Pade approximants diverge from each other at somewhat higher temperatures than we originally found, it is less clear what this implies concerning the presence or absence of high-temperature superconductivity in the t-J model.Comment: 4 pages, 5 eps figures included; ERRATUM 2 pages, 3 eps figures correcting the error in the series for superconducting susceptibilitie

Legislative Smoking Bans for Reducing Exposure to Secondhand Smoke and Smoking Prevalence: Opportunities for Georgians

Background: Secondhand smoke, which is also referred to as environmental tobacco smoke and passive smoke, is a known human carcinogen. Secondhand smoke also causes disease and premature death in nonsmoking adults and children. Methods: We summarize studies of secondhand smoke in public places before and after smoking bans, as well as studies of cardiovascular and respiratory disease before and after such bans. Results: To protect the public from the harmful effects of secondhand smoke, smoke-free legislation is an effective public health measure. Smoking bans in public places, which have been implemented in many jurisdictions across the U.S. and in other countries, have the potential to influence social norms and reduce smoking behavior. Conclusions: Through legislative smoking bans for reducing secondhand smoke exposure and smoking prevalence, opportunities exist to protect the health of Georgians and other Americans and to reduce health care costs. These opportunities include increasing the comprehensiveness of smoking bans in public places and ensuring adequate funding to quit line services

Implications of Current Federal Aviation Regulatory Policies Governing Low Time Commercial Pilots who Transition to Single Pilot/IFR Environments

The purpose of this study was to investigate the need to change FAA policy governing commercial pilot training and experience by soliciting the expertise from chief pilots and directors of flight operations who were members of the National Air Transportation Association (NATA). A descriptive survey questionnaire was specifically developed for this study to investigate attitudes and beliefs about the adequacy of a commercial pilot new hire\u27s previous flight experience. The study found that a substantial number of aviation professionals believe that a new hire\u27s previous pilot-in-command (PIC) experience in a single-pilot environment is inadequate. Major concerns include inadequate previous experience as PIC in a single pilot environment flying high performance multi-engine aircraft, inadequate instrument meteorological conditions (IMC) experience, substandard IMC experience at night, inadequate mountainous experience, and inadequate flight experience in hazardous conditions (icing conditions, slippery runways, etc.). Quality of flight time and experience were addressed as it related to commercial pilots. Recommendations were made to change existing FAA policies for new hire commercial pilots who transition to single pilot, multi-engine charter operations without any prior experience

Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station

During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference