Field investigations of the performance of air bag deployments in frontal collisions

This paper documents field investigations of “air bag” crashes selected from a large group of air bag crashes in file at the University of Michigan Transportation Research Institute (UMTRI). A full range of crashes are presented with injury levels of AIS 1–2 to AIS 5–6. Most occupants sustained minor injuries. Those not wearing the lap-shoulder belt (3-point belt) had more minor injuries than the restrained. The occurrence of higher level injuries (AIS 2) was found more often in the nonbelted.     

Combustion synthesis of advanced materials: Part II. Classification, applications and modelling

Combustion (self propagating high temperature) synthesis (SHS) reactions have been classified into (i) simple reaction systems in which no other processing step, other than the SHS reaction, is considered; (ii) SHS reactions which involve simultaneous and/or subsequent densification process(es); (iii) SHS reactions coupled with vapor transport systems and those which synthesize specific products such as functionally-graded materials (FGM), thin films and coatings, and mechanically alloyed powders or those used to join dissimilar ceramics and/or intermetallics. Finally, a comparison is made of the various mathematical models that have been developed to simulate and predict instabilities in propagating combustion synthesis reactions.     

An experimental test of computed responses of bismuth germanate to gamma rays

Experimental spectra of the γ-rays from ⁶⁰Ca, ²²Na, ²⁰⁷Bi and ¹³⁷Cs were used to calibrate and obtain spectra from a 3.17 cm diameter by 0.65 cm thick BGO scintillation spectrometer. These spectra were compared to the results of detailed Monte Carlo simulations. Tables of coefficients for polynomials to give absorption coefficients are presented.     

Human albumin solder supplemented with TGF-beta 1 accelerates healing following laser welded wound closure

BACKGROUND AND OBJECTIVE: We examined the possibility that human albumin solder can be used as a vehicle for site specific delivery of growth factors for the purpose of accelerating tissue repair following laser welded wound closure. Certain human recombinant growth factors have been shown to accelerate wound healing in model systems. Pilot in vitro studies have established that several growth factors, including TGF-beta 1, maintain bioactivity following exposure to temperatures achieved during laser tissue welding. Using a temperature controlled laser delivery system (TCL) to precisely maintain welding temperatures, it is now possible to avoid thermal denaturation of exogenous bioactive molecules such as growth factors. STUDY DESIGN/MATERIALS AND METHODS: HB-EGF, bFGF, and TGF-beta 1 were tested in vitro for maintenance of bioactivity after exposure to 80 degrees C. In vivo experiments using porcine skin determined the efficacy of solders augmented with growth factors. Incisions were repaired using human albumin alone or supplemented with HB-EGF (2 micrograms), bFGF (10 micrograms), or TGF-beta 1 (1 microgram). Wounds were excised at 3, 5, and 7 days post-operatively. Tensile strength, total collagen content, and histology were performed. RESULTS: At 3 days, tensile strength (TS) of TGF-beta 1 wounds were 36% (P < 0.05) and 20% (n.s.) stronger than laser alone and suture closures, respectively. By 5 days the TS of the TGF-beta 1 group increased by 50% (P < 0.05) and 59% (P < 0.02) over laser alone and suture groups, respectively. At 7 days the TGF-beta 1 group was 50% (P < 0.05) and 79% (P < 0.01) stronger than laser solder alone or suture, respectively. The HB-EGF and bFGF groups were equivalent to the laser solder group at all time points. Total collagen TGF-beta 1 Accelerates Healing Following Laser Welding content at 7 days increased in the TGF-beta 1 group by 7% (n.s.) over the suture group and 21% (P < 0.05) in the laser group. CONCLUSION: Human albumin solder supplemented with TGF-beta 1 increases the early post-operative strength of laser welded wounds. This novel application of laser tissue soldering augmented with a growth factor has the potential to bring about immediate fluid tight seals while providing site specific delivery of biological modifiers. This may lead to an overall improvement in post-operative convalescence, wound infections, and hospital costs.     

Comments on `Stabilisability and detectability of discrete-timetime-varying systems' by J.C. Engwerder

An alleged counterexample in the above-titled paper (ibid., vol.35, no.4, pp.425-429, Apr. 1990) to a main result of B.D.O. Anderson and J.B. Moore (SIAM J. Contr. Optimiz., vol.19, no.1, pp.22-32, 1981) is shown not to be a counterexample in actuality     

Preparing tomorrow's health sciences librarians: feasibility and marketing studies

The University of North Carolina at Chapel Hill is devising and evaluating five curricular models designed to improve education for health sciences librarianship. These models fit into a continual learning process from the initial professional preparation to lifelong learning opportunities. Three of them enhance existing degree and certificate programs in the School of Information and Library Science (SILS) with a health sciences specialization, and two are new programs for working information professionals. The approaches involve partnerships among SILS, the Health Sciences Library, and the program in Medical Informatics. The planning process will study the feasibility of the proposed programs, test the marketability of the models to potential students and employers, and make recommendations about implementation.     

Comparative study of intra-airway gas transport by alternative modes of ventilation

The effectiveness of three alternative modes of ventilation [high-frequency ventilation (HFV), constant-flow ventilation (CFV), and high-frequency external vibration ventilation (HFVV)] was compared. Local intra-airway gas transport was measured with catheters placed in the distal trachea and in bronchi located 5.5, 9, and 11 cm from the carina. A new bolus dispersion method was devised to measure the local effective diffusivities (Deff) induced by these modes of ventilation and by cardiogenic oscillations relative to molecular diffusivity (Dmol). Mixing induced by cardiogenic oscillations was 7 +/- 2- to 26 +/- 4-fold greater than by molecular diffusion alone. Intra-airway transport by CFV, applied at three flow rates (0.3, 1.0, and 3.0 l.min-1.kg-1), was most effective in the trachea but fell sharply in the more peripheral airways. Local transport by HFVV, at a frequency of 22 Hz and a vertical amplitude of 0.4 cm, was most effective in the periphery (Deff = 793 x Dmol), whereas the effectiveness of transport by HFV, applied with 10 and 20 ml at 22 Hz, was evenly distributed. Doubling the HFV oscillatory volume caused a 4.5 +/- 2.7-fold increase in Deff/Dmol. Combining HFVV with CFV at 0.3 l.min-1.kg-1 induced transport rates that were 187- to 2,034-fold greater than by molecular diffusion alone in the bronchi and a higher relative transport (due to convection) in the trachea. We conclude that the combination of HFVV with low-flow CFV provides a high rate of intra-airway transport with minimal mechanical perturbations to the pulmonary system.     

A mechanically verified language implementation

This paper briefly describes a programming language, its implementation on a microprocessor via a compiler and link-assembler, and the mechanically checked proof of the correctness of the implementation. The programming language, called Piton, is a high-level assembly language designed for verified applications and as the target language for high-level language compilers. It provides executeonly programs, recursive subroutine call and return, stack based parameter passing, local variables, global variables and arrays, a user-visible stack for intermediate results, and seven abstract data types including integers, data addresses, program addresses and subroutine names. Piton is formally specified by an interpreter written for it in the computational logic of Boyer and Moore. Piton has been implemented on the FM8502, a general purpose microprocessor whose gate-level design has been mechanically proved to implement its machine code interpreter. The FM8502 implementation of Piton is via a function in the Boyer-Moore logic which maps a Piton initial state into an FM8502 binary core image. The compiler and link-assembler are both defined as functions in the logic. The implementation requires approximately 36K bytes and 1400 lines of prettyprinted source code in the Pure Lisp-like syntax of the logic. The implementation has been mechanically proved correct. In particular, if a Piton state can be run to completion without error, then the final values of all the global data structures can be ascertained from an inspection of an FM8502 core image obtained by running the core image produced by the compiler and link-assembler. Thus, verified Piton programs running on FM8502 can be thought of as having been verified down to the gate level.This work was supported in part by the Defense Advanced Research Projects Agency under DARPA Orders 6082 and 9151, contract MDA904-87-C-H009.