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At least 73 records · Page 4

Predicting Postoperative Injury and Military Discharge Status After Knee Surgery in the US Army

Background: Researchers have assessed postoperative injury or disability predictors in the military setting but typically focused on 1 type of surgical procedure at a time, used relatively small sample sizes, or investigated mixed cohorts with civilian populations. Purpose: To identify the relationship between baseline variables and injury incidence or military discharge status in US Army soldiers after knee surgery. Study Design: Case-control study; Level of evidence, 3. Methods: Data were obtained from a repository containing personnel, performance, and medical records for all active-duty US Army soldiers. Multivariate logistic regressions were used to estimate the effects of numerous variables on postoperative injury or on medical discharge. Variable selection and model validation were conducted using the k-fold method. Results: A total of 7567 soldiers underwent knee surgery between 2017 and 2019. Meniscal procedures were the most common type of surgery (39%), and approximately 71% of the cohort had a postoperative injury. Significant predictors for sustaining a postoperative injury included having a previous nonknee injury (odds ratio [OR], 1.5), female sex (OR, 1.3), and Black race (OR, 1.2). Within 4 years after surgery, 17% of soldiers were discharged from the military because of knee-related disability. Significant predictors for discharge from duty included enlisted rank (OR, 2.3), recent fitness test failure (OR, 1.9), number of previous knee surgeries (OR, 1.7), and having a previous nonknee injury (OR, 1.6). Conclusion: After knee surgery, nearly three-fourths of the soldiers in this cohort sustained a postoperative injury and almost one-fifth of soldiers were medically discharged from the military within 4 years. This study identified variables that indicate statistically increased risk for these postoperative outcomes and highlighted potentially modifiable factors.

Orthopedics↗

Stingray Case Study

Improvised explosive devices (IEDs) have injured and killed numerous soldiers and civilians as a consequence of military operations in the Middle East. With gaps in existing technologies, the US military required devices for quickly addressing deadly IEDs without harming military personnel or inflicting severe damage to the environment. In response to this need, Sandia developed Stingray, a clear, plastic handheld device to quickly and safely disable threatening IEDs. Stingray is designed to be used in two configurations: a coherent water blade for cutting operations and as a water slug for general device disruption. Prior to disabling an IED, Explosive Ordnance Disposal (EOD) technicians will x-ray the target using tools such as Sandia's X-ray Toolkit (XTK) to determine which function operators should use to dismantle the IED. For example, if the operator knows exactly which wires to cut, they can use the precision water blade. If the operator wants to create a general disruption, they can use the water slug function.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Optical Engine Lockout System Design and Operation

Engine run days in the Diesel Combustion and Fuel Effects Lab are hectic. The long mental lists that must be kept by engine operators, paired with the tight time constraints between experiments, can cause operational issues that may be dangerous to personnel and/or cause damage to test equipment. Until now, a paper sign has been used to warn operators not to motor the engine when a foreign object has been placed inside of it. Unfortunately, this simple administrative control has failed in the past, motivating this effort to develop an improved system. The lockout system described in this document introduces an engineering control that, when activated, actually prevents the engine from being motored. The new system consists of a primary and a secondary control panel. Prior to an operator placing a foreign object into the cylinder, they press a button on the secondary control panel near the engine. This breaks the interlock circuit for the engine dynamometer and activates LEDs on both control panels to notify operators that a foreign object is present within the engine cylinder. Once the work is done and all foreign objects have been removed from the combustion chamber, two operators must be present to disable the system by simultaneously pressing the buttons on the primary and secondary control panels. Requiring a second operator to disable the system increases accountability and reduces the likelihood of potentially costly mistakes.

42 ENGINEERING↗

Community Resilience Indicator Analysis: Commonly Used Indicators from Peer-Reviewed Research (Updated for Research Published 2003-2021)

In 2017, FEMA’s National Integration Center (NIC) Technical Assistance (TA) Branch identified a need to establish a data-driven basis for prioritizing locations for TA investment and guiding local emergency management planning. To achieve this goal, FEMA tasked Argonne National Laboratory (Argonne) with identifying commonly used indicators of community resilience across the landscape of published peer-reviewed research. FEMA and Argonne completed the first Community Resilience Indicator Analysis (CRIA) in 2018 and repeated the process in 2022. The CRIA process begins with a literature review and cataloguing of published peer-reviewed assessment methodologies on social vulnerability and community resilience. The literature review findings are then filtered by inclusion criteria established by the CRIA research team to ensure the methodologies are: (1) Quantitative, (2) Data and methodology are publicly available, (3) Calculated at the county level or lower, (4) Examine generalized hazard risk (rather than a singular hazard), and (5) Focused on pre-disaster community conditions. After this, the research team identifies the commonly used indicators across these methodologies and selects the best data source for each indicator. Finally, the research team bins the data for visual display, conducts a correlation analysis and creates a composite index, the FEMA Community Resilience Index (FEMA CRI). In 2018, the CRIA identified eight resilience and vulnerability assessment methodologies and 20 commonly used indicators (indicators used in three or more of the eight methodologies). The FEMA CRI in 2018 was created from these 20 indicators and was produced for at the county level. The 2022 CRIA updated the literature review to expand the list of methodologies examined and followed the same process, resulting in an analysis of 14 methodologies published between 2003 and 2021 and 22 indicators identified as commonly used (indicators used in five or more of the 14 methodologies). In 2022, the research team produced the FEMA CRI at the county and the census tract levels. To make the CRIA data more accessible and more actionable, each individual indicator and the FEMA CRI is binned and included in FEMA’s Resilience Analysis and Planning Tool (RAPT). RAPT enables emergency managers and community partners to quickly visualize relative differences in potential resilience by county, tribe and census tract. By reviewing the data for each of these 22 indicators individually, emergency managers can gain insights for targeted outreach strategies, planning, mitigation investments and response and recovery operations. Communities, regional governments and others can use this data to better understand potential challenges to resilience. As the social science field of examining and validating indicators of resilience evolves, FEMA will update RAPT to provide emergency managers and community partners with additional data and tools to inform planning, mitigation, response and recovery. It is important to understand that the role of the emergency manager is not to change or to “improve” the data, but to plan appropriately for the community characteristics reflected in the data. These datasets are community characteristics that researchers have identified as important considerations for resilience. For example, people with disabilities may have greater challenges to be resilient to disasters. If a community has a high population of people with disabilities, the emergency manager(s) may need to create tailored preparedness outreach programs and strategies to ensure those residents have support if evacuation is necessary. Rather than label these indicators as an absolute measure of resilience, FEMA considers “potential challenges to resilience” a better frame to understand these indicators. Everyone is vulnerable to disasters. While scholars theorize that certain characteristics may make an individual or a household more socially vulnerable, the data does not reflect measures that individuals and/or communities have taken to address potential challenges, such as emergency management planning and outreach or household preparedness measures. To aid emergency managers in understanding how to use these indicators, calling them potential challenges to resilience supports a more positive and strategic application of the data in all phases of emergency management.

99 GENERAL AND MISCELLANEOUS↗

Global disease burden linked to diet high in red meat and colorectal cancer from 1990 to 2019 and its prediction up to 2030

Background Numerous studies have already identified an association between excessive consumption of red meat and colorectal cancer (CRC). However, there has been a lack of detailed understanding regarding the disease burden linked to diet high in red meat and CRC. Objective We aim to offer evidence-based guidance for developing effective strategies that can mitigate the elevated CRC burden in certain countries. Methods We used the data from the Global Burden of Disease (GBD) Study 2019 to evaluate global, regional, and national mortality rates and disability-adjusted Life years (DALYs) related to diet high in red meat. We also considered factors such as sex, age, the socio-demographic index (SDI), and evaluated the cross-national inequalities. Furthermore, we utilized DALYs data from 204 countries and regions to measure cross-country inequalities of CRC by calculating the slope index of inequality and concentration index as standard indicators of absolute and relative inequalities. Discussion The results show that globally, the age-standardized mortality rate (ASMR) and age-standardized disability adjusted life year rate (ASDR) related to CRC due to diet high in red meat have decreased, with estimated annual percent change (EAPCs) of −0.32% (95% CI −0.37 to −0.28) and-0.18% (95% CI −0.25 to −0.11). Notably, the burden was higher among males and the elderly. The slope index of inequality rose from 22.0 (95% CI 18.1 to 25.9) in 1990 to 32.9 (95% CI 28.3 to 37.5) in 2019 and the concentration index fell from 59.5 (95% CI 46.4 to 72.6) in 1990 to 48.9 (95% CI 34.6 to 63.1) in 2019. Also, according to our projections, global ASDR and ASMR might tend to increase up to 2030. Conclusion ASMR and ASDR for CRC associated with high red meat diets declined globally from 1990 to 2019, but the absolute number of cases is still rising, with men and the elderly being more affected. CRC associated with diets high in red meat exhibits significant income inequality, placing a disproportionate burden on wealthier countries. Moreover, according to our projections, ASMR and ASDR are likely to increase globally by 2030. In order to address this intractable disease problem, understanding changes in global and regional epidemiologic trends is critical for policy makers and others.

Yang, Xuesong↗

MicroRNAs in blood and cerebrospinal fluid as diagnostic biomarkers of multiple sclerosis and to monitor disease progression

Multiple sclerosis is a chronic autoimmune disease of the central nervous system. It is the main cause of non-traumatic neurological disability in young adults. Multiple sclerosis mostly affects people aged 20–50 years; however, it can occur in young children and much older adults. Factors identified in the distribution of MS include age, gender, genetics, environment, and ethnic background. Multiple sclerosis is usually associated with progressive degrees of disability. The disease involves demyelination of axons of the central nervous system and causes brain and spinal cord neuronal loss and atrophy. Diagnosing multiple sclerosis is based on a patient’s medical history including symptoms, physical examination, and various tests such as magnetic resonance imaging, cerebrospinal fluid and blood tests, and electrophysiology. The disease course of multiple sclerosis is not well correlated with the biomarkers presently used in clinical practice. Blood-derived biomarkers that can detect and distinguish the different phenotypes in multiple sclerosis may be advantageous in personalized treatment with disease-modifying drugs and to predict response to treatment. The studies reviewed have shown that the expression levels of a large number of miRNAs in peripheral blood, serum, exosomes isolated from serum, and cerebrospinal fluid are altered in multiple sclerosis and can distinguish the disease phenotypes from each other. Further studies are warranted to independently validate these findings so that individual or pairs of miRNAs in serum or cerebrospinal fluid can be used as potential diagnostic markers for adult and pediatric multiple sclerosis and for monitoring disease progression and response to therapy.

60 APPLIED LIFE SCIENCES↗

Determining Off-Cycle Fuel Economy Benefits of 2-Layer HVAC Technology

This work presents a methodology to determine the off-cycle fuel economy benefit of a 2-Layer HVAC system which reduces ventilation and heat rejection losses of the heater core versus a vehicle using a standard system. Experimental dynamometer tests using EPA drive cycles over a broad range of ambient temperatures were conducted on a highly instrumented 2016 Lexus RX350 (3.5L, 8 speed automatic). These tests were conducted to measure differences in engine efficiency caused by changes in engine warmup due to the 2-Layer HVAC technology in use versus the technology being disabled (disabled equals fresh air-considered as the standard technology baseline). These experimental datasets were used to develop simplified response surface and lumped capacitance vehicle thermal models predictive of vehicle efficiency as a function of thermal state. These vehicle models were integrated into a database of measured on road testing and coupled with U.S. typical meteorological data to simulate vehicle efficiency across seasonal thermal and operational conditions for hundreds of thousands of drive cycles. Fuel economy benefits utilizing the 2-Layer HVAC technology are presented in addition to goodness of fit statistics of the modeling approach relative to the experimental test data.

2-layer technology↗

Time bases, discretes, and interrupts

The effort performed to assure proper flight program handling of time bases, discretes, and interrupts was discussed. The following time bases are used as key mission events: guidance reference release, liftoff, S-1B low level sensors dry, S-1B outboard engines cutoff, S-IVB cutoff, and S-IVB de-orbit DCS command. The five discrete outputs in the discrete output register were verified for proper setting. Each discrete input is honored in the proper time frame by forcing each discrete in the following intervals: before the discrete is enabled, after the discrete has been detected, and after the discrete has been disabled. As an assurance that an interrupt is honored only in the proper time frames, each interrupt was forced during the following intervals: prior to the specified enable time, after the interrupt has been honored, after the interrupt has been disabled.

Source record↗

Health and safety evaluation of a modified tunnel borer design for application to single entry coal mine development

A health and safety analysis of a single entry coal tunnel borer system is given. The results of the health analysis indicated that while the tunnel borer design offered improvements in dust control through the use of water sprays, a higher face ventilation rule, and the application of spalling rather than the conventional grinding process, it interjected an additional mutagen and toxic compound into the environment through the use of shotcrete. The tunnel borer system easily conformed with the prescribed fatality limit, but exceeded the required limits for disabling and overall injuries. It also exhibited projected disabling and overall injury rates considerably higher than existing continuous mining injury rates. Consequently, the tunnel borer system was not considered an advanced system.

Zimmerman, W. F.↗

Control of submersible vortex flows

Vortex flows produced by submersibles typically unfavorably influence key figures of merit such as acoustic and nonacoustic stealth, control effectiveness/maneuverability, and propulsor efficiency/body drag. Sources of such organized, primarily longitudinal, vorticity include the basic body (nose and sides) and appendages (both base/intersection and tip regions) such as the fairwater, dive planes, rear control surfaces, and propulsor stators/tips. Two fundamentally different vortex control approaches are available: (1) deintensification of the amplitude and/or organization of the vortex during its initiation process; and (2) downstream vortex disablement. Vortex control techniques applicable to the initiation region (deintensification approach) include transverse pressure gradient minimization via altered body cross section, appendage dillets, fillets, and sweep, and various appendage tip and spanload treatment along with the use of active controls to minimize control surface size and motions. Vortex disablement can be accomplished either via use of control vortices (which can also be used to steer the vortices off-board), direct unwinding, inducement of vortex bursting, or segmentation/tailoring for enhanced dissipation. Submersible-applicable vortex control technology is also included derived from various aeronautical applications such as mitigation of the wing wake vortex hazard and flight aircraft maneuverability at high angle of attack as well as the status of vortex effects upon, and mitigation of, nonlinear control forces on submersibles. Specific suggestions for submersible-applicable vortex control techniques are presented.

Bushnell, D. M.↗

Abnormal fault-recovery characteristics of the fault-tolerant multiprocessor uncovered using a new fault-injection methodology

An investigation was made in AIRLAB of the fault handling performance of the Fault Tolerant MultiProcessor (FTMP). Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once in every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles Byzantine or lying faults. Byzantine faults behave such that the faulted unit points to a working unit as the source of errors. The design's problems involve: (1) the design and interface between the simplex error detection hardware and the error processing software, (2) the functional capabilities of the FTMP system bus, and (3) the communication requirements of a multiprocessor architecture. These weak areas in the FTMP's design increase the probability that, for any hardware fault, a good line replacement unit (LRU) is mistakenly disabled by the fault management software.

Padilla, Peter A.↗

Fault recovery characteristics of the fault tolerant multi-processor

The fault handling performance of the fault tolerant multiprocessor (FTMP) was investigated. Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles byzantine or lying faults. It is pointed out that these weak areas in the FTMP's design increase the probability that, for any hardware fault, a good LRU (line replaceable unit) is mistakenly disabled by the fault management software. It is concluded that fault injection can help detect and analyze the behavior of a system in the ultra-reliable regime. Although fault injection testing cannot be exhaustive, it has been demonstrated that it provides a unique capability to unmask problems and to characterize the behavior of a fault-tolerant system.

Padilla, Peter A.↗

Future Assets, Student Talent (FAST)

Future Assets, Student Talent (FAST) motivates and prepares talented students with disabilities to further their education and achieve High Tech and professional employment. The FAST program is managed by local professionals, business, and industry leaders; it is modeled after High School High Tech project TAKE CHARGE started in Los Angeles in 1983. Through cooperative efforts of Alabama Department of Education, Vocational Rehabilitation, Adult and Children Services, and the President's Committee on Employment of People with Disabilities, north central Alabama was chosen as the second site for a High School High Tech project. In 1986 local business, industry, education, government agencies, and rehabilitation representatives started FAST. The program objectives and goals, results and accomplishments, and survey results are included.

Source record↗

A robotic wheelchair

Many people who are mobility impaired are incapable, for a variety of reasons, of using an ordinary wheelchair. These people must rely on either a power wheelchair, which they control, or another person to push and guide them while they are in an ordinary or power wheelchair. Power wheelchairs can be difficult to operate. If a person has additional disabilities, either in perception or fine motor control of their hands, a power chair can be difficult or impossible for them to use safely. Having one person push and guide a person who is mobility impaired is very expensive, and if the disabled person is otherwise independent, very inefficient and frustrating. This paper describes a low-cost robotic addition to a power wheelchair that assists the rider of the chair in avoiding obstacles, going to pre-designated places, and maneuvering through doorways and other narrow or crowded areas. This system can be interfaced to a variety of input devices, and can give the operator as much or as little moment by moment control of the chair as they wish.

Miller, David P.↗

The Rural Outreach Project

The Rural Outreach Project was designed to increase the diversity of NASA's workforce by: 1) Conducting educational research designed to investigate the most effective strategies for expanding innovative, NASA-sponsored pre-college programs into rural areas; 2) Field-testing identified rural intervention strategies; 3) Implementing expanded NASA educational programs to include 300 rural students who are disabled, female and/or minority; and 4) Disseminating project strategies. The Project was a partnership that included NASA Langley Research Center's Office of Education, Norfolk State University, Cooperative Hampton Roads Organizations for Minorities in Engineering (CHROME) and Paul D. Camp Community College. There were four goals and activities identified for this project; 1) Ascertain effective strategies for expanding successful NASA-sponsored urban-based, pre-college programs into rural settings; 2) Field test identified rural intervention strategies; 3) Publish or disseminate two reports, concerning project research and activities at a national conference; 4) Provide educational outreach to 300, previously underserved, rural students who are disabled, female and /or minority.

Coleman, Clarence D.↗

Idiopathic orthostatic intolerance and postural tachycardia syndromes

Upright posture imposes a substantial gravitational stress on the body, for which we are able to compensate, in large part because of the autonomic nervous system. Alteration in autonomic function, therefore, may lead to orthostatic intolerance. On one extreme, patients with autonomic failure caused by degenerative loss of autonomic function are severely disabled by orthostatic hypotension and may faint whenever they stand up. Fortunately, such patients are relatively rare. On the other hand, disabling orthostatic intolerance can develop in otherwise normal young people. These patients can be severely impaired by symptoms of fatigue, tachycardia, and shortness of breath when they stand up. The actual incidence of this disorder is unknown, but these patients make up the largest group of patients referred to centers that specialize in autonomic disorders. We will review recent advances made in the understanding of this condition, potential pathophysiological mechanisms that contribute to orthostatic intolerance, therapeutic alternatives currently available for the management of these patients, and areas in which more research is needed.

Review↗

MEMS CLOSED CHAMBER HEAT ENGINE AND ELECTRIC GENERATOR

A heat engine, preferably combined with an electric generator, and advantageously implemented using micro-electromechanical system (MEMS) technologies as an array of one or more individual heat engine/generators. The heat engine is based on a closed chamber containing a motive medium, preferably a gas; means for alternately enabling and disabling transfer of thermal energy from a heat source to the motive medium; and at least one movable side of the chamber that moves in response to thermally-induced expansion and contraction of the motive medium, thereby converting thermal energy to oscillating movement. The electrical generator is combined with the heat engine to utilize movement of the movable side to convert mechanical work to electrical energy, preferably using electrostatic interaction in a generator capacitor. Preferably at least one heat transfer side of the chamber is placed alternately into and out of contact with the heat source by a motion capacitor, thereby alternately enabling and disabling conductive transfer of heat to the motive medium.

Landis, Geoffrey A.↗

Pseudorandom Switching for Adding Radar to the AFF Sensor

A document describes the proposed addition of a radar function to the Autonomous Formation Flying Sensor, making possible coarse relative-position control to prevent collisions in the event of failure of one of the spacecraft. According to the proposal, in addition to tracking GPS-like one-way ranging signals transmitted by the other normally functioning spacecraft, each spacecraft could simultaneously track the reflection of its own ranging signal from a disabled, non-transmitting spacecraft. From the round-trip travel time, the approximate distance to the disabled spacecraft could be estimated. To prevent jamming of the receiver by the transmitter on the same spacecraft, the receiver would be switched off during transmission.

Tien, Jeffrey↗