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Background: Biomarkers are needed for frailty, a common phenotype often associated with muscle loss in older people. Plasma gelsolin (pGSN) is a protein largely synthesized and secreted by skeletal muscle. Aims: To investigate whether pGSN could be a biomarker of the frailty phenotype and predict mortality. Methods: A homogenous cohort of males (born 1919–1934, baseline n = 3490) has been followed since the 1960s. In 2010/11, frailty phenotypes by modified Fried criteria were assessed. pGSN was measured in a convenience subset (n = 469, mean age 83) and re-measured in survivors (n = 127) in 2017. Mortality through December 31, 2018 was retrieved from national registers. Regression models were used for analyses. Results: Of 469 males, 152 (32.4%) were robust, 284 (60.6%) prefrail, and 33 (7.0%) frail in 2010/11. There was a graded (p = 0.018) association between pGSN (mean 58.1 ug/mL, SD 9.3) and frailty. After multivariable adjustment, higher pGSN levels were associated with lower odds of having contemporaneous phenotypic prefrailty (OR per 1 SD 0.73, 95% CI 0.58–0.92) and frailty (OR per 1 SD 0.70, 95% CI 0.44–1.11). By 2018, 179 males (38.2%) had died, and higher baseline pGSN predicted a lower 7-year mortality rate (HR per 1 SD 0.85, 95% CI 0.72–1.00). pGSN concentrations in 2010/11 and 2017 were correlated (n = 127, r = 0.34, p < 0.001). Discussion: Higher baseline pGSN concentrations were associated with a persistently robust phenotype and lower mortality rate over 7 years in a cohort of octogenarian males with high socioeconomic status and may be a promising laboratory biomarker for the development of a frailty phenotype.

How do people answer polar questions? In this fourteen-language study of answers to questions in conversation, we compare the two main strategies; first, interjection-type answers such as uh-huh (or equivalents yes, mm, head nods, etc.), and second, repetition-type answers that repeat some or all of the question. We find that all languages offer both options, but that there is a strong asymmetry in their frequency of use, with a global preference for interjection-type answers. We propose that this preference is motivated by the fact that the two options are not equivalent in meaning. We argue that interjection-type answers are intrinsically suited to be the pragmatically unmarked, and thus more frequent, strategy for confirming polar questions, regardless of the language spoken. Our analysis is based on the semantic-pragmatic profile of the interjection-type and repetition-type answer strategies, in the context of certain asymmetries inherent to the dialogic speech act structure of question–answer sequences, including sequential agency and thematic agency. This allows us to see possible explanations for the outlier distributions found in ǂĀkhoe Haiǁom and Tzeltal.

Principal cells of the medial nucleus of the trapezoid body (MNTB) are simple round neurons that receive a large excitatory synapse (the calyx of Held) and many small inhibitory synapses on the soma. Strangely, these neurons also possess one or two short

Results of a preliminary study to evaluate the feasibility of optical telemetry on an EM launched projectile are discussed. At issue are the relative intensities of the optical noise received in the MCL catch tank from the muzzle flash versus the narrowband optical signal levels generated from tiny emitters onboard a projectile after being launched in the MCL., The views, opinions, and/or findings contained in this report are those of the author(s) and should not be considered as an official Department of the Army position, policy, or decision, unless so designated by other documentation., The original document contains color images.

The muzzle voltage in solid-armature railguns is an important diagnostic because it can provide information about the state of the rail-armature interface. Sudden jumps in the muzzle voltage can indicate that an armature has made a transition from low voltage to arcing contact. However, in many tests, the muzzle voltage increases gradually, and the onset of transition as indicated by the muzzle voltage is ambiguous. This report describes research aimed at developing alternative approaches for detecting the onset of arcing contact in solid armature railguns. The work, conducted at the IAT in the early part of 2006, sought to determine whether there is information in the 20 kHz-500 MHz range of the power spectrum that correlates strongly with the onset of transition to arcing contact. To this end, we analyzed two types of signals collected during railgun tests for information that might indicate the onset of arcing. One was a high-frequency muzzle voltage measurement recorded with a 1 GHz sampling rate. The other signal was broad band electromagnetic (EM) radiation (also sampled at 1 GHz) collected using a 2-meter dipole antenna in the vicinity of the railgun. The results show that there is some correlation between the high-frequency and conventional muzzle voltage measurements, and there is little correlation between the broadband EM radiation measurement and the conventional muzzle voltage measurement. The high-frequency muzzle voltage measurement does not appear to contain information about the electrical state of the rail-armature interface that could be used to indicate the presence of arcing., The original document contains color images.

Since past investigations have shown that radio frequency (RF) signal transmission in the bore of a railgun can be practical, the feasibility of using time domain reflectometry and well-established transmission line theory is investigated as a means to determine armature position during launch. This report describes the transmission line model of the HEMCL and initial measurements suggesting that such an approach might be used to provide dynamic armature position profiles. However, subsequent continuous wave analyses of RF transmission line measurements shows that the electrical transmission line characteristics of the HEMCL railgun make it unfeasible to use RF time-domain reflectometry to characterize its dynamic behavior. The laminated containment structure enclosing copper rails of the HEMCL form a very lossy, poorly matched transmission line making it impractical to couple the RF signal into it; high RF attenuation diminishes that portion of the signal that it is coupled. Measurements showed that signals below 900 MHz are completely reflected at the 50-ohm/HEMCL-muzzle nterface. A fraction of RF signals at higher frequencies (900-2400 MHz) can be coupled, but will attenuate by 20 dB or more after propagating only a few tens of centimeters., The views, opinions, and/or findings contained in this report are those of the author(s) and should not be considered as an official Department of the Army position, policy, or decision, unless so designated by other documentation. The original document contains color images.

A microwave-frequency Doppler system was developed and implemented in a single-stage gas gun to develop an in-bore velocity profile. The technique uses a 24.15 GHz microwave transceiver to measure the Doppler frequency change as the projectile travels down the bore. The difference of the source signal and the shifted signal was digitally extracted by a mixer and recorded by a digital oscilloscope. From each recorded signal, the Doppler frequency shift information was deduced, providing a detailed projectile velocity profile of each shot., The original document contains color images. All DTIC reproductions will be in black and white.

This paper addresses the accurate measurement of the transverse armature-sabot motion during a railgun shot. One way to make such measurements is to use three orthogonally arranged piezorestive accelerometers made by ENDEVCO. Model 7270A-200k is a tiny unit rated for measurements up to 200 kGee. Each unit costs about $ 1,500 and has a specified 4-kGee uncertainty due to "non-linearity and hysteresis" and a 5 percent "transverse sensitivity." There are "Zero shifts" - an output voltage corresponding to 0 acceleration, and the unit can be highly susceptible to electromagnetic interference (EMI). Assuming a railgun-launched armature experiences a 10 percent transverse/longitudinal acceleration ratio, a 100-kGee axial launch will result in a transverse measurement uncertainty on the same order of magnitude as the measurement itself. Expense and measurement uncertainty are the principal liabilities of the piezorestive-accelerometer method for measuring transverse acceleration. The new method, below, addresses these liabilities.

As pan of an investigation to determine the feasibility of HSTSS telemetry techniques in EM launchers, a series of experiments was conducted to evaluate the performance of magnetic shields. The magnetic field was measured at several positions along the bore centerline of the MCL under stationary operation, and comparable EMAP3D calculations were performed. The qualitative agreement between experimental and computational results was very good. Hollow, metallic cylindrical shields were considered for their capacity to suppress the transient magnetic fields. One, comprised of A17075, weighed 130 g; the other, of ETP Cu, weighed 430 g. The copper shield was observed to reduce the induced peak voltages by more than 80%, which occurred at the earliest stages of the current rise. However, after 250 microsec, the induced voltages were no longer attenuated by the shield. Improved shielding may be obtained with thicker or more electrically conductive cylindrical shells. If the induced fields are found to be problematic in actual EM launches, a more sophisticated shield design will be needed since the significant weight added to a 200-g launch package by this design would render its use impractical., Original contains color plates: All DTIC reproductions will be in black and white.

This paper describes an experimental investigation of the feasibility of microwave telemetry for conveying diagnostic information collected during and after launch from an electromagnetic (EM) gun. The study focused on extending the Hardened Subminiature Telemetry Sensor Systems (HSTSS) technology for use in EM launch environments. While HSTSS technology has already been successfully demonstrated in high-g, high-pressure launch environments in conventional gun systems, it has not yet been tested in an EM gun environment, where the launch accelerations are generally higher and where the projectile can be exposed to high magnetic fields and EM transients. In this work, ultra high frequency (UHF) telemetry measurements were made at fixed locations in the magnetized bore of the Medium Caliber Launcher (MCL) at the IAT to assess the effect of the EM environment on telemetry and the HSTSS-like components. The data show that UHF FM signals can both propagate and be received in this non-optimal environment. Signals were received with minimal loss after propagating along the entire bore as well as through the containment wall. To examine the effect of high, transient magnetic fields on HSTSS-like components, the telemetry package was located both ahead of and behind a stationary armature, with the latter case simulating the higher fields in an EM launch with a muzzle shunt. The results showed that, in an EM launch without a muzzle shunt, the telemetry package could be positioned far enough ahead of the armature such that there would be no interference in the received telemetry signals. However, when a muzzle shunt was simulated, there were momentary disruptions in the transmitted signal coincident with fast rising, transient magnetic fields. The use of a thick metallic cylindrical shield surrounding the telemetry components reduced the induced voltages due to transient magnetic fields somewhat and slightly improved the observed telemetry signal., This article is from ADA404787 10th U.S. Army Gun Dynamics Symposium Proceedings

A previous paper reported the computational simulation of a resistive rail cladding in a 40 mm bore railgun. In that study, it was found that a 1 mm thick resistive rail cladding (10 mW.cm or 50 mW.cm) on a copper rail (2 mW.cm) resulted in an additional electrical loss equal to about 5% of the muzzle energy, corresponding to a reduction in the overall launch efficiency of less than 1%. This report extends the previous cladding study to a 90 mm bore, near full-scale railgun. The base rail material resistivity has been increased to 4.5 W-cm, typical of the low density alloys that may be needed in a practical launcher. It is found that a 1 mm resistive cladding in the near full-scale launcher has only one half the impact on efficiency calculated previously for a 40 mm bore. For example, a 100 mW.cm cladding results in an additional electrical loss equal to 2.4% of the muzzle kinetic energy, resulting in reduction in overall launcher efficiency of less than 1/2%.

A fast method of parsing noisy speech is sketched. It is then used to study the entropy of languages. (Author)

This report presents the results of a project to evaluate the performance properties of recently developed water-based and low-solvent architectural coatings to determine if these products have properties equivalent to the conventional high-solvent products which are now used for the same purposes. Architectural coatings are paints and related products applied to stationary structures such as buildings and plant facilities. The classes of coatings evaluated included clear finishes, opaque stains, metal primers, wall primers, wood primers, tile-like glazes, waterproof coatings, maintenance topcoats, swimming pool paints and mastic coatings. These classes, and five other classes for which no samples were available, are exempt from the Air Resources Board's model rule for maximum solvent content because no suitable water-based or low-solvent coatings were available at the time the rule was adopted. Standard ASTM test methods were used. Some of the new products tested had performance properties equivalent to or better than the conventional high-solvent architectural coating products.