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Polybrominated diphenyl ethers (PBDEs) are ubiquitous persistent organic pollutants (POPs) that are known neuroendocrine disrupting chemicals with adverse neurodevelopmental effects. PBDEs may act as risk factors for autism spectrum disorders (ASD), characterized by abnormal psychosocial functioning, although direct evidence is currently lacking. Using a translational exposure model, we tested the hypothesis that maternal transfer of a commercial mixture of PBDEs, DE-71, produces ASD-relevant behavioral and neurochemical deficits in female offspring. C57Bl6/N mouse dams (F0) were exposed to DE-71 via oral administration of 0 (VEH/CON), 0.1 (L-DE-71) or 0.4 (H-DE-71) mg/kg bw/d from 3 wk prior to gestation through end of lactation. Mass spectrometry analysis indicated in utero and lactational transfer of PBDEs (in ppb) to F1 female offspring brain tissue at postnatal day (PND) 15 which was reduced by PND 110. Neurobehavioral testing of social novelty preference (SNP) and social recognition memory (SRM) revealed that adult L-DE-71 F1 offspring display deficient short- and long-term SRM, in the absence of reduced sociability, and increased repetitive behavior. These effects were concomitant with reduced olfactory discrimination of social odors. Additionally, L-DE-71 exposure also altered short-term novel object recognition memory but not anxiety or depressive-like behavior. Moreover, F1 L-DE-71 displayed downregulated mRNA transcripts for oxytocin (Oxt) in the bed nucleus of the stria terminalis (BNST) and supraoptic nucleus, and vasopressin (Avp) in the BNST and upregulated Avp1ar in BNST, and Oxtr in the paraventricular nucleus. Our work demonstrates that developmental PBDE exposure produces ASD-relevant neurochemical, olfactory processing and behavioral phenotypes that may result from early neurodevelopmental reprogramming within central social and memory networks.

Polybrominated diphenyl ethers (PBDEs) are ubiquitous persistent organic pollutants (POPs) that are known neuroendocrine disrupting chemicals with adverse neurodevelopmental effects. PBDEs may act as risk factors for autism spectrum disorders (ASD), characterized by abnormal psychosocial functioning, although direct evidence is currently lacking. Using a translational exposure model, we tested the hypothesis that maternal transfer of a commercial mixture of PBDEs, DE-71, produces ASD-relevant behavioral and neurochemical deficits in female offspring. C57Bl6/N mouse dams (F0) were exposed to DE-71 via oral administration of 0 (VEH/CON), 0.1 (L-DE-71) or 0.4 (H-DE-71) mg/kg bw/d from 3 wk prior to gestation through end of lactation. Mass spectrometry analysis indicated in utero and lactational transfer of PBDEs (in ppb) to F1 female offspring brain tissue at postnatal day (PND) 15 which was reduced by PND 110. Neurobehavioral testing of social novelty preference (SNP) and social recognition memory (SRM) revealed that adult L-DE-71 F1 offspring display deficient short- and long-term SRM, in the absence of reduced sociability, and increased repetitive behavior. These effects were concomitant with reduced olfactory discrimination of social odors. Additionally, L-DE-71 exposure also altered short-term novel object recognition memory but not anxiety or depressive-like behavior. Moreover, F1 L-DE-71 displayed downregulated mRNA transcripts for oxytocin (Oxt) in the bed nucleus of the stria terminalis (BNST) and supraoptic nucleus, and vasopressin (Avp) in the BNST and upregulated Avp1ar in BNST, and Oxtr in the paraventricular nucleus. Our work demonstrates that developmental PBDE exposure produces ASD-relevant neurochemical, olfactory processing and behavioral phenotypes that may result from early neurodevelopmental reprogramming within central social and memory networks.

Polybrominated diphenyl ethers (PBDEs) are ubiquitous persistent organic pollutants (POPs) that are known neuroendocrine disrupting chemicals with adverse neurodevelopmental effects. PBDEs may act as risk factors for autism spectrum disorders (ASD), characterized by abnormal psychosocial functioning, although direct evidence is currently lacking. Using a translational exposure model, we tested the hypothesis that maternal transfer of a commercial mixture of PBDEs, DE-71, produces ASD-relevant behavioral and neurochemical deficits in female offspring. C57Bl6/N mouse dams (F0) were exposed to DE-71 via oral administration of 0 (VEH/CON), 0.1 (L-DE-71) or 0.4 (H-DE-71) mg/kg bw/d from 3 wk prior to gestation through end of lactation. Mass spectrometry analysis indicated in utero and lactational transfer of PBDEs (in ppb) to F1 female offspring brain tissue at postnatal day (PND) 15 which was reduced by PND 110. Neurobehavioral testing of social novelty preference (SNP) and social recognition memory (SRM) revealed that adult L-DE-71 F1 offspring display deficient short- and long-term SRM, in the absence of reduced sociability, and increased repetitive behavior. These effects were concomitant with reduced olfactory discrimination of social odors. Additionally, L-DE-71 exposure also altered short-term novel object recognition memory but not anxiety or depressive-like behavior. Moreover, F1 L-DE-71 displayed downregulated mRNA transcripts for oxytocin (Oxt) in the bed nucleus of the stria terminalis (BNST) and supraoptic nucleus, and vasopressin (Avp) in the BNST and upregulated Avp1ar in BNST, and Oxtr in the paraventricular nucleus. Our work demonstrates that developmental PBDE exposure produces ASD-relevant neurochemical, olfactory processing and behavioral phenotypes that may result from early neurodevelopmental reprogramming within central social and memory networks.

Intranasal recombinant osteopontin (OPN) has been shown to be neuroprotective in different models of acquired brain injury but has never been tested after traumatic brain injury (TBI). We used a model of moderate-to-severe controlled cortical impact in male adult Sprague Dawley rats and tested our hypothesis that OPN treatment would improve neurological outcomes, lesion and brain tissue characteristics, neuroinflammation, and vascular characteristics at 1 day post-injury. Intranasal OPN administered 1 hr after the TBI did not improve neurological score, lesion volumes, blood-brain barrier, or vascular characteristics. When assessing neuroinflammation, we did not observe any effect of OPN on the astrocyte reactivity but discovered an increased number of activated microglia within the ipsilateral hemisphere. Moreover, we found a correlation between edema and heme oxygenase-1 (HO-1) expression which was decreased in OPN-treated animals, suggesting an effect of OPN on the HO-1 response to injury. Thus, OPN may increase or accelerate the microglial response after TBI, and early response of HO-1 in modulating edema formation may limit the secondary consequences of TBI at later time points. Additional experiments and at longer time points are needed to determine if intranasal OPN could potentially be used as a treatment after TBI where it might be beneficial by activating protective signaling pathways.

Recirculation, from arterial inflow routes through venous outflow pathways, was conceptualized in stroke research 50 years ago. As new technologies were developed, blocked arteries could be reopened, capillaries could be reperfused, and the use of recanalization and reperfusion grew to dominate therapeutic strategies. These approaches overwhelmingly focused on restoration of arterial and capillary inflow, but not on veins even though venous disorders may initiate or exacerbate brain injury. In this commentary, we advance the term "recirculation" after "recanalization" and "reperfusion" as a primary concept of stroke pathophysiology that targets the restoration of both the arterial and venous cerebral circulations.

Mild traumatic brain injuries can lead to long-lasting cognitive and motor deficits, increasing the risk of future behavioral, neurological, and affective disorders. Our study focused on long-term behavioral deficits after repeated injury in which mice received either a single mild CHI (mCHI), a repeated mild CHI (rmCHI) consisting of one impact to each hemisphere separated by 3 days, or a moderate controlled cortical impact injury (CCI). Shams received only anesthesia. Behavioral tests were administered at 1, 3, 5, 7, and 90 days post-injury (dpi). CCI animals showed significant motor and sensory deficits in the early (1-7 dpi) and long-term (90 dpi) stages of testing. Interestingly, sensory and subtle motor deficits in rmCHI animals were found at 90 dpi. Most importantly, depression-like behaviors and social passiveness were observed in rmCHI animals at 90 dpi. These data suggest that mild concussive injuries lead to motor and sensory deficits and affective disorders that are not observed after moderate TBI.

Mild traumatic brain injuries can lead to long-lasting cognitive and motor deficits, increasing the risk of future behavioral, neurological, and affective disorders. Our study focused on long-term behavioral deficits after repeated injury in which mice received either a single mild CHI (mCHI), a repeated mild CHI (rmCHI) consisting of one impact to each hemisphere separated by 3 days, or a moderate controlled cortical impact injury (CCI). Shams received only anesthesia. Behavioral tests were administered at 1, 3, 5, 7, and 90 days post-injury (dpi). CCI animals showed significant motor and sensory deficits in the early (1-7 dpi) and long-term (90 dpi) stages of testing. Interestingly, sensory and subtle motor deficits in rmCHI animals were found at 90 dpi. Most importantly, depression-like behaviors and social passiveness were observed in rmCHI animals at 90 dpi. These data suggest that mild concussive injuries lead to motor and sensory deficits and affective disorders that are not observed after moderate TBI.

AimTo determine neuropsychological tests likely to predict cognitive decline.MethodsA sample of nonconverters (n = 106) was compared with those who declined in cognitive status (n = 24). Significant univariate logistic regression prediction models were used to create multivariate logistic regression models to predict decline based on initial neuropsychological testing.ResultsRey-Osterrieth Complex Figure Test (RCFT) Retention predicted conversion to mild cognitive impairment (MCI) while baseline Buschke Delay predicted conversion to Alzheimer's disease (AD). Due to group sample size differences, additional analyses were conducted using a subsample of demographically matched nonconverters. Analyses indicated RCFT Retention predicted conversion to MCI and AD, and Buschke Delay predicted conversion to AD.ConclusionResults suggest RCFT Retention and Buschke Delay may be useful in predicting cognitive decline.

AimTo determine neuropsychological tests likely to predict cognitive decline.MethodsA sample of nonconverters (n = 106) was compared with those who declined in cognitive status (n = 24). Significant univariate logistic regression prediction models were used to create multivariate logistic regression models to predict decline based on initial neuropsychological testing.ResultsRey-Osterrieth Complex Figure Test (RCFT) Retention predicted conversion to mild cognitive impairment (MCI) while baseline Buschke Delay predicted conversion to Alzheimer's disease (AD). Due to group sample size differences, additional analyses were conducted using a subsample of demographically matched nonconverters. Analyses indicated RCFT Retention predicted conversion to MCI and AD, and Buschke Delay predicted conversion to AD.ConclusionResults suggest RCFT Retention and Buschke Delay may be useful in predicting cognitive decline.

BackgroundGender is increasingly recognized as an important influence on brain development, disease susceptibility, and response to pharmacologic/rehabilitative treatments. In regenerative medicine, it remains entirely unknown whether there is an interaction between transplanted stem cells and host gender that might bias efficacy and safety in some patients but not others.MethodsWe examined the role of recipient gender in a neonatal rat hypoxic-ischemic injury (HII) model, treated with female human neuronal stem cells (hNSCs), labeled with superparamagnetic iron oxide particles implanted into the contralateral cerebral ventricle. We monitored HII evolution (by magnetic resonance imaging, histopathology, behavioral testing) and hNSC fate (migration, replication, viability).ResultsRecipient gender after implantation did not influence the volume or location of ischemic injury (1, 30, or 90 d) or behavior (90 d). Superparamagnetic iron oxide labeling did not influence HII evolution. Implantation had its greatest benefit on mild/moderate injuries, which remained stable rather than increasing as in severe HII as is the natural history for such lesions.ConclusionOur results suggest that hNSC treatment (including using hNSCs that are prelabeled with iron to allow tracking in real time by magnetic resonance imaging) would be equally safe and effective for male and female human newborns with mild-to-moderate HII.

BackgroundGender is increasingly recognized as an important influence on brain development, disease susceptibility, and response to pharmacologic/rehabilitative treatments. In regenerative medicine, it remains entirely unknown whether there is an interaction between transplanted stem cells and host gender that might bias efficacy and safety in some patients but not others.MethodsWe examined the role of recipient gender in a neonatal rat hypoxic-ischemic injury (HII) model, treated with female human neuronal stem cells (hNSCs), labeled with superparamagnetic iron oxide particles implanted into the contralateral cerebral ventricle. We monitored HII evolution (by magnetic resonance imaging, histopathology, behavioral testing) and hNSC fate (migration, replication, viability).ResultsRecipient gender after implantation did not influence the volume or location of ischemic injury (1, 30, or 90 d) or behavior (90 d). Superparamagnetic iron oxide labeling did not influence HII evolution. Implantation had its greatest benefit on mild/moderate injuries, which remained stable rather than increasing as in severe HII as is the natural history for such lesions.ConclusionOur results suggest that hNSC treatment (including using hNSCs that are prelabeled with iron to allow tracking in real time by magnetic resonance imaging) would be equally safe and effective for male and female human newborns with mild-to-moderate HII.

Traumatic brain injury (TBI) is common in young children and adolescents and is associated with long-term disability and mortality. The neuropathologic sequelae that result from juvenile TBI are a complex cascade of events that include edema formation and brain swelling. Brain aquaporin-4 (AQP4) has a key role in edema formation. Thus, development of novel treatments targeting AQP4 to reduce edema could lessen the neuropathologic sequelae. We hypothesized that inhibiting AQP4 expression by injection of small-interfering RNA (siRNA) targeting AQP4 (siAQP4) after juvenile TBI would decrease edema formation, neuroinflammation, neuronal cell death, and improve neurologic outcomes. The siAQP4 or a RNA-induced silencing complex (RISC)-free control siRNA (siGLO) was injected lateral to the trauma site after controlled cortical impact in postnatal day 17 rats. Magnetic resonance imaging, neurologic testing, and immunohistochemistry were performed to assess outcomes. Pups treated with siAQP4 showed acute (3 days after injury) improvements in motor function and in spatial memory at long term (60 days after injury) compared with siGLO-treated animals. These improvements were associated with decreased edema formation, increased microglial activation, decreased blood-brain barrier disruption, reduced astrogliosis and neuronal cell death. The effectiveness of our treatment paradigm was associated with a 30% decrease in AQP4 expression at the injection site.

Mild traumatic brain injury (mTBI) has become an increasing public health concern as subsequent injuries can exacerbate existing neuropathology and result in neurological deficits. This study investigated the temporal development of cortical lesions using magnetic resonance imaging (MRI) to assess two mTBIs delivered to opposite cortical hemispheres. The controlled cortical impact model was used to produce an initial mTBI on the right cortex followed by a second injury induced on the left cortex at 3 (rmTBI 3d) or 7 (rmTBI 7d) days later. Histogram analysis was combined with a novel semi-automated computational approach to perform a voxel-wise examination of extravascular blood and edema volumes within the lesion. Examination of lesion volume 1d post last injury revealed increased tissue abnormalities within rmTBI 7d animals compared to other groups, particularly at the site of the second impact. Histogram analysis of lesion T2 values suggested increased edematous tissue within the rmTBI 3d group and elevated blood deposition in the rm TBI 7d animals. Further quantification of lesion composition for blood and edema containing voxels supported our histogram findings, with increased edema at the site of second impact in rmTBI 3d animals and elevated blood deposition in the rmTBI 7d group at the site of the first injury. Histological measurements revealed spatial overlap of regions containing blood deposition and microglial activation within the cortices of all animals. In conclusion, our findings suggest that there is a window of tissue vulnerability where a second distant mTBI, induced 7d after an initial injury, exacerbates tissue abnormalities consistent with hemorrhagic progression.

Mild traumatic brain injury (mTBI) has become an increasing public health concern as subsequent injuries can exacerbate existing neuropathology and result in neurological deficits. This study investigated the temporal development of cortical lesions using magnetic resonance imaging (MRI) to assess two mTBIs delivered to opposite cortical hemispheres. The controlled cortical impact model was used to produce an initial mTBI on the right cortex followed by a second injury induced on the left cortex at 3 (rmTBI 3d) or 7 (rmTBI 7d) days later. Histogram analysis was combined with a novel semi-automated computational approach to perform a voxel-wise examination of extravascular blood and edema volumes within the lesion. Examination of lesion volume 1d post last injury revealed increased tissue abnormalities within rmTBI 7d animals compared to other groups, particularly at the site of the second impact. Histogram analysis of lesion T2 values suggested increased edematous tissue within the rmTBI 3d group and elevated blood deposition in the rm TBI 7d animals. Further quantification of lesion composition for blood and edema containing voxels supported our histogram findings, with increased edema at the site of second impact in rmTBI 3d animals and elevated blood deposition in the rmTBI 7d group at the site of the first injury. Histological measurements revealed spatial overlap of regions containing blood deposition and microglial activation within the cortices of all animals. In conclusion, our findings suggest that there is a window of tissue vulnerability where a second distant mTBI, induced 7d after an initial injury, exacerbates tissue abnormalities consistent with hemorrhagic progression.

Massachusetts Institute of Technology, Alfred P. Sloan School of Management. Thesis. 1973. M.S., MICROFICHE COPY ALSO AVAILABLE IN DEWEY LIBRARY., Includes bibliographical references.

On 20 December 1974, two hangfires occurred in a developmental 155-mm howitzer at Aberdeen Proving Ground (APG), MD. The second hangfire was accompanied by a rupturing of the howitzer breech. As a result of this, a laboratory study was initiated to uncover possible causes leading to the malfunction. The study involved testing of various components of the igniter train singly and in various combinations under a variety of environmental conditions. The sequence of events leading to the hangfires was as follows: the primer ignited the base pad, which did not ignite the propellant nor the black powder containing central core "snake". The NC tube ignited to a fizz burn after a period of seconds and eventually ignited the propellant that caused the hangfires. The ignition occurred in a localized region near the breech, leading to the pressure waves of extreme magnitude. Subsequent high pressures that ruptured the breech may have come about because of propellant grain fracture due to pressure wave induced acceleration against the projectile. The difference between the apparently reliable operation of the XM123E2 interim propellant charge and the charge (XM203E1) used in the hangfires and in this study was due to the change in igniter train cloths. This was confirmed by post-firing analysis of cloth residues, visual differences in cloth density, and full-scale blowout cannon results.

A study reviewing the existing Army Distance Learning Plan (ADLP) and current Distance Learning practices, with a focus on the Army's training and educational challenges and the benefits of applying Distance Learning techniques. The ASB study panel makes six specific recommendations, the most important of which is Accelerating CourseWare (CW) development. The panel also recommends placing heavier reliance on DL Collaborative which should pay huge dividends. A crucial improvement to the total program is establishing an Army DL Futures Lab. The study concluded accelerated DL CW applications will provide quicker ROI through reduced TDY and per diem costs and reductions in overall DL implementation costs.

The problem of optimal guidance design for the low altitude, subsonic, vertical plane approach maneuver of an air vehicle constrained to maintain view of a fixed final position is studied using a nonlinear, constrained, optimal control problem formulation. Multiple, competing optimization criteria are included separately as performance goals and in combination as state equality constraints for design tradeoff analysis. In conjunction with vehicle flight constraints, a sensor line-of -sight (LOS) angle limit is imposed as a control variable inequality constraint to provide a sensor field of regard influence on the guidance design. Numerical results are provided that illustrate the optimal guidance for different performance criteria, the sensor LOS profile along the optimal maneuvers, and the influence of the sensor limit on the guidance law design. A near-optimal, closed-loop feedback guidance law that incorporates the sensor constraint is developed based on neighboring extremals.

The problem of optimal guidance design for the low altitude, subsonic, vertical plane approach maneuver of an air vehicle constrained to maintain view of a fixed final position is studied using a nonlinear, constrained, optimal control problem formulation. Multiple, competing optimization criteria are included separately as performance goals and in combination as state equality constraints for design tradeoff analysis. In conjunction with vehicle flight constraints, a sensor line-of -sight (LOS) angle limit is imposed as a control variable inequality constraint to provide a sensor field of regard influence on the guidance design. Numerical results are provided that illustrate the optimal guidance for different performance criteria, the sensor LOS profile along the optimal maneuvers, and the influence of the sensor limit on the guidance law design. A near-optimal, closed-loop feedback guidance law that incorporates the sensor constraint is developed based on neighboring extremals.

In 1983, the United States Air Force Global Weather Central (AFGWC) implemented a new model to map and store an analysis of worldwide cloud-cover derived from surface and satellite data. This model, the designated the Real- Time Nephanalysis (RTNEPH) model, contains analyses of total sky cover, cloud bases, and cloud heights. Studies assessing the accuracy of the RTNEPH database have, up to now, been limited. In this work, the RTNEPH total sky-cover database is evaluated against independent surface observations. Since the RTNEPH algorithm heavily weights available surface observations, this was not a simple task; more than 500,000 independent surface and RTNEPH observations had to be matched and evaluated. Frequency distributions of the differences in these two sources were computed and stratified by latitude, season, time of day (day versus night), and age. Finally, statistical tests were run to obtain quantitative assessments of the results. In general, the RTNEPH total sky cover compared favorably with the surface reports, but there were differences. Certain biases in the RTNEPH were also identified, most notably the underestimation of cloud cover in arctic regions and the poor resolution of RTNEPH in regions where the airways surface observation code is used.

Oil consumption was measured in a modern production diesel engine using tritium as a radiotracer. The measurements were made primarily at two speeds and one load using first a single-grade lubricant and then a multi-grade lubricant. These values were then compared to oil flow rates up/down the liner which were based on film thickness traces of a sister engine under the same loads and speeds. The traces were obtained using the laser-fluorescence technique. For the most part, it was discovered that there does not seem to exist a correlation between these flow rates and oil consumption. However, the traces do reveal that the crown land is dry on all four strokes and thus does not contribute to the engine's oil consumption. A larger data base is necessary in order to accurately compare oil consumption to the film traces. This is currently in progress as of this writing. (JS)

Oil consumption was measured in a modern production diesel engine using tritium as a radiotracer. The measurements were made primarily at two speeds and one load using first a single-grade lubricant and then a multi-grade lubricant. These values were then compared to oil flow rates up/down the liner which were based on film thickness traces of a sister engine under the same loads and speeds. The traces were obtained using the laser-fluorescence technique. For the most part, it was discovered that there does not seem to exist a correlation between these flow rates and oil consumption. However, the traces do reveal that the crown land is dry on all four strokes and thus does not contribute to the engine's oil consumption. A larger data base is necessary in order to accurately compare oil consumption to the film traces. This is currently in progress as of this writing. (JS)

Sixteen years of typhoon data were studied, in an effort to develop a technique for forecasting tropical cyclone intensity changes in the Northwestern Pacific. The data base provided average changes for 24 and 48 hour periods along with the average duration of each phase (intensifying and dissipating). Further study revealed that the upper-level outflow patterns provide a means to adjust these average changes so a more realistic forecast could be generated for the individual storms. Forecasts were further improved by studying how land and other environmental features effect the life cycle of tropical cyclones. Results from the research were compiled and incorporated into a series of flow charts. These charts were created to enable individuals to quickly determine future intensities of cyclones given the storm's history and a current satellite picture.

A new concept in seekers has been developed by integrating the sensor with an Optical Data Processor (ODP). The resulting system, in a terminal guidance submissile configuration, will recognize a tank if there is one in the field of view, discriminate between friend and foe, and provide guidance signals to home in on the target. The system will fit in a 150 mm diameter by 20 mm section, and consume less than one watt of power. The system will have retargeting and damage assessment capabilities. This new concept is the culmination of a number of years of research in optical data processing at the Missile Command, focusing on three main problems: real time data input, sensitivity to orientation or aspect, and size of the system. The first problem was solved by contractural development of a liquid crystal coherent image modulator, the second problem by the in-house invention of a multiplexed filter, and the third problem with the development of an ODP system which operates with a laser diode. This development opens the door to move ODP from the laboratory into Army application. (Author)

A 'super-smart weapon' which outperforms our smart weapons just going into the field, yet is much cheaper than those current systems? It sounds like the answer to the Army's prayer for a method to cope with a dramatically increasing threat. We think we have demonstrated the key ingredients of such a system, through the marriage of a long-term fundamental effort at the Missile Command, significant industrial developments, and recognition of how this developing technology can pay off for the Army. Through the application of some recent existing developments in optical data processing, we can now propose to build a seeker which recognizes a tank by its image, homes on it, and destroys it. The seeker autonomously detects and locks on the target, provides guidance signals, reacquires if the target is lost, and retargets if necessary. The sensor will fit in a submissile, weigh under a pound, consume less than a watt of power, and possibly even cost under $100!

This thesis investigates many of the issues surrounding the civil maritime navigation dilemma facing the USCG. At present, LORAN-C and OMEGA, which are hyperbolic radionavigation systems and TRANSIT, a Doppler shift satellite-based system, are the main systems employed in the civil maritime field. NAVSTAR GPS, a passive ranging satellite navigation system is, in the meantime, showing great promise as the replacement system for primary radionavigation in the U.S. There are several key questions, one involving national security, which must be answered, however, before NAVSTAR becomes operational. What positional accuracy will be made available to the civil community? What are the economics of the user equipments? Will NAVSTAR be accepted as a successful replacement for LORAN by the civil community? To aid in answering some of these questions, the results of an informal survey of the civil maritime industry are presented. The final outcome remains to be seen. These issues will require careful thought by this country's top leaders before any final committment to NAVSTAR can be made or prior to any decision to discontinue LORAN-C or OMEGA. (Author)

A device which uses an electrically fired primer (M52A3B1) to actuate the mechanical firing pin in the 155-mm, 175-mm, and 8-inch gun systems has been developed. It may be used as a direct replacement for the standard lanyard-operated firing mechanism, M35. The advantage of this device is that the standard percussion primers (M82 or similar) used in these gun systems may be actuated remotely (i.e., without the use of the lanyard), under the control of an electronic sequence timer and/or computer system. The data acquistion process is simplified because the beginning of the ignition sequence may now be time-correlated with other events. More accurate timing of ignition delays results because the initiation signal to the electric primer serves as a reference point, and the delay between application of the initiation voltage and the beginning of output from the percussion primer is less than a millisecond., Supersedes Rept. no. BRL-IMR-485 daqted Mar 76.

A method of detecting chemical agents present in a sample by utilizing a spectrometer to produce an output spectrum which is transmitted to an optical correlator which processes the output spectra of the spectrometer and identifies particular chemical species present in the sample by utilizing a detector and indicator arrangement. Patent applications. (mjm)

A method of adjusting a laser diode relative to a solid optical correlator body to adjust the optical axis of the laser diode relative to a matched filter mounted in a predetermined position on the solid optical correlator body and then securing the laser diode in the predetermined position to provide an aligned optical correlator for receiving correlator signals from a predetermined scene to correlate the scene with that of the matched filter. Patent Applications. (rh)

A hybrid optical correlator which uses a Fourier plane detector to cause adjustment of an image of an object in scale and orientation so that a matched filter can provide a correlation of the object independent of scale and orientation. Patent Applications. (rh)

Remote measuring of an angle is very difficult if the angle to be measured is in the plane containing the observer. This patent application describes a technique using cylindrical lenses and patterns which provide a binary coded image to the remote observer. The binary code read out is the angle in the plane containing the observer. Use of microscreens allows the system to be very thin, and even curved around a curved surface, such as a missile. It can be used to continuously record the yaw angle of a missile during test flight.

This report describes a missile having a sensor in the nose thereof. The nose is in the shape of a transparent ogive window which has an index of refraction that assumes different values at different positions on the window whereas the window appears to the sensor as if it were a hemispherical window.

A holographic optical element structure which corrects the aberrated waveform that has passed through an ogive shaped sensor window. The corrected waveform will have the same structure as if it had passed through a hemispherical window. Such structure allows one to replace the nose of a laser designator, (hemispherical) with an ogive shaped nose without the loss of optical performance. (Author)

Apparatus which corrects optical aberrations produced by an ogive shaped window on a laser seeker system. A holographic optical element is provided which breaks the received radiation, at the proper wavelength, into four components and focuses each component into a separate detector. The gain of each detector amplifier is adjusted according to the direction the gimbled seeker is pointed thus allowing the guidance control system to operate without offset even though the received radiation is aberrated by the ogive shaped window. (Author)

A technique for automatically varying the gain of a lock-in-amplifier with logarithmically responding diodes placed in the feedback network so that the output is proportional to the logarithm of the input. Measurement of low or high level signals without manual changes of gain is then provided. The lock-in-amplifier is a combination of narrow band preamplification, phase sensitive detection, and DC amplification. It is typically used to detect very low level signals submerged in noise. The disadvantage is that in many measurements there are large and small signals. If the gain level is set to detect the small signals, the large ones overload the system. If the gain is set to detect large signals, the small ones are lost. Trial and error repetitions are required to correctly adjust. A solution to this is to use a logarithmic amplifier. Many such slow responding amplifiers could be used after the lock-in, but then the dynamic range of the system is low. A logarithmic preamplifier can be used, but then it must be a very low noise amplifier, and the very low noise amplifier in the lock-in is wasted.

It is an object of this invention to make possible the measurement of the far field properties of full scale LADAR targets. An optical reflective device is provided that includes a laser source mounted relative to a first optical device so as to illuminate said device and cause laser energy to be transmitted therefrom in a back focal plane and to be focused onto a second optical device mounted relative to said first optical device to receive laser energy in a front focal plane of the second optical device. A target is mounted in a back focal plane of the second optical device and a beam splitter is mounted between the first and second optical device so that laser energy reflected from the target and onto the beam splitter will be displayed on the detector in forms of far field pattern of the target.

The report describes a holographic optical element that performs a zoom operation in a stepwise fashion while undergoing a simple rotation. Each of four holographic plates is produced by a different optical arrangement. Each plate contains a number of exposures arranged in a ring. The four plates are paired with the exposures in the ring of one plate in proper register with the exposures in the second plate. The resulting pair of holograms form on-axis holographic lenses. The two pair are combined to produce the holographic zoom lens.

This thesis investigates many of the issues surrounding the civil maritime navigation dilemma facing the USCG. At present, LORAN-C and OMEGA, which are hyperbolic radionavigation systems and TRANSIT, a Doppler shift satellite-based system, are the main systems employed in the civil maritime field. NAVSTAR GPS, a passive ranging satellite navigation system is, in the meantime, showing great promise as the replacement system for primary radionavigation in the U.S. There are several key questions, one involving national security, which must be answered, however, before NAVSTAR becomes operational. What positional accuracy will be made available to the civil community? What are the economics of the user equipments? Will NAVSTAR be accepted as a successful replacement for LORAN by the civil community? To aid in answering some of these questions, the results of an informal survey of the civil maritime industry are presented. The final outcome remains to be seen. These issues will require careful thought by this country's top leaders before any final committment to NAVSTAR can be made or prior to any decision to discontinue LORAN-C or OMEGA.

The purpose of this paper is to explain the unphased array concept and to demonstrate detection of simulated targets with this approach. Application is in the area of air defense systems.

Contents: Foormulation of objectives Forecasting and planning Organization development Planning managerial manpower Product planning Return on investment Financial planning Reevaluation and revision Case studies Bibliography., Available from the Bureau of Business Research, IIndiana University. Price unknown. Copies not available to DDC or Clearinghouse customers.

This thesis is a continuation of a series of studies on automatic throttle compensation systems begun in 1963. Previous investigations have been concerned with flight in a wings level attitude. This study will consider the effects of turning flight on the system. The system under consideration here is the Automatic power Compensator, (APC), an automatic throttle in use in the F-8 and F-4 aircraft. It utilizes feedbacks of angle of attack and normal acceleration. It was found important to differentiate between spurious perturbations and those perturbations from steady introduced due to the aircraft entering a turn.

The patent concerns a system for measuring the temperature of a cryogenic environment including an RC circuit provided with a source of reference voltage with a resistance sensor disposed within the environment and connected to a trigger. A pulser is connected to supply the RC circuit and a temperature indicator is connected to a pulser and trigger to count the RC interval for determination of the temperature of the environment. (Modified author abstract)

A report is given on studies involving the line shapes obtained by ultrasonic paramagnetic resonance and by electron paramagnetic resonance methods in ruby at 4.2K and having a Cr(3+) concentration ranging from 0.05% to 1.2%., Presented at the Army Science Conference (1966), U. S. Military Academy, West Point, N. Y., 14-17 June 1966. Complete proceedings available in two unclassified volumes as AD-634 615 and AD-634 616 and one classified volume available to qualified DDC users.

This thesis is a continuation of a series of studies on automatic throttle compensation systems begun in 1963 by Lieutenant Commander G. R, Bell. £l] Previous investigations have been concerned with flight in a wings level attitude. This study will consider the effects of turning flight on the system. The system under consideration here is the Specialties, Incorporated, Automatic Power Compensator, (APC), an automatic throttle in use in the F-8 and F-4 aircraft. It utilizes feedbacks of angle of attack and normal acceleration. It was found important to differentiate between spurious perturbations and those perturbations from steady state introduced due to the aircraft entering a turn. This study was conducted by Lieutenant Richard D. Hartman at the United States Naval Postgraduate School, Monterey, California. The assistance given by Professor E. J. Andrews is greatly appreciated by the writer.

CIVINS (Civilian Institutions) Thesis document, Oil consumption was measured in a modern production diesel engine using tritium as a radiotracer. The measurements were made primarily at two speeds and one load using first a single-grade lubricant and then a multi-grade lubricant. These values were then compared to oil flow rates up/down the liner which were based on film thickness traces of a sister engine under the same loads and speeds. The traces were obtained using the laser-fluorescence technique. For the most part, it was discovered that there does not seem to exist a correlation between these flow rates and oil consumption. However, the traces do reveal that the crown land is dry on all four strokes and thus does not contribute to the engine's oil consumption. A larger data base is necessary in order to accurately compare oil consumption to the film traces. This is currently in progress as of this writing. (JS), http://archive.org/details/tritiummethodoil1094524332, U.S. Naval Postgraduate School, CIVINS program, Approved for public release; distribution is unlimited.

This thesis is a continuation of a series of studies on automatic throttle compensation systems begun in 1963 by Lieutenant Commander G. R, Bell. £l] Previous investigations have been concerned with flight in a wings level attitude. This study will consider the effects of turning flight on the system. The system under consideration here is the Specialties, Incorporated, Automatic Power Compensator, (APC), an automatic throttle in use in the F-8 and F-4 aircraft. It utilizes feedbacks of angle of attack and normal acceleration. It was found important to differentiate between spurious perturbations and those perturbations from steady state introduced due to the aircraft entering a turn. This study was conducted by Lieutenant Richard D. Hartman at the United States Naval Postgraduate School, Monterey, California. The assistance given by Professor E. J. Andrews is greatly appreciated by the writer., http://archive.org/details/aninvestigationo109459545, Lieutenant, United States Navy, Approved for public release; distribution is unlimited.

This thesis investigates many of the issues surrounding the civil maritime navigation dilemma facing the USCG. At present, LORAN-C and OMEGA, which are hyperbolic radionavigation systems and TRANSIT, a Doppler shift satellite-based system, are the main systems employed in the civil maritime field. NAVSTAR GPS, a passive ranging satellite navigation system is, in the meantime, showing great promise as the replacement system for primary radionavigation in the U.S. There are several key questions, one involving national security, which must be answered, however, before NAVSTAR becomes operational. What positional accuracy will be made available to the civil community? What are the economics of the user equipments? Will NAVSTAR be accepted as a successful replacement for LORAN by the civil community? To aid in answering some of these questions, the results of an informal survey of the civil maritime industry are presented. The final outcome remains to be seen. These issues will require careful thought by this country's top leaders before any final committment to NAVSTAR can be made or prior to any decision to discontinue LORAN-C or OMEGA., http://archive.org/details/satellitenavigat1094518859, Lieutenant, United States Coast Guard, Approved for public release; distribution is unlimited.