Secondary electric power generation with minimum engine bleed

Secondary electric power generation with minimum engine bleed is discussed. Present and future jet engine systems are compared. The role of auxiliary power units is evaluated. Details of secondary electric power generation systems with and without auxiliary power units are given. Advanced bleed systems are compared with minimum bleed systems. A cost model of ownership is given. The difference in the cost of ownership between a minimum bleed system and an advanced bleed system is given

A Tool for Developing Diagnostics for a Digital Switching System

Testing large digital systems is difficult. Throughout the literature on “design for testability,” the existence of diagnostic software is assumed. However, developing such software is a significant task. A hardware test fixture was developed to assist in the development of diagnostic software for a Stromberg-Carlson Corporation switching system. Two circuit boards were designed, constructed, and debugged

Systems study for an Integrated Digital-Electric Aircraft (IDEA)

The results of the Integrated Digital/Electric Aircraft (IDEA) Study are presented. Airplanes with advanced systems were, defined and evaluated, as a means of identifying potential high payoff research tasks. A baseline airplane was defined for comparison, typical of a 1990's airplane with advanced active controls, propulsion, aerodynamics, and structures technology. Trade studies led to definition of an IDEA airplane, with extensive digital systems and electric secondary power distribution. This airplane showed an improvement of 3% in fuel use and 1.8% in DOC relative to the baseline configuration. An alternate configuration, an advanced technology turboprop, was also evaluated, with greater improvement supported by digital electric systems. Recommended research programs were defined for high risk, high payoff areas appropriate for implementation under NASA leadership

Quantitative scintigraphy with deconvolutional analysis for the dynamic measurement of hepatic function

A mathematical technique known as deconvolutional analysis was used to provide a critical and previously missing element in the computations required to quantitate hepatic function scintigraphically. This computer-assisted technique allowed for the determination of the time required, in minutes, of a labeled bilirubin analog (99mTc-disofenin) to enter the liver via blood and exit via bile. This interval was referred to as the mean transit time (MTT). The critical process provided for by deconvolution is the mathematical simulation of a bolus injection of tracer directly into the afferent blood supply of the liver. The raw data required for this simulation are obtained from the intravenous injection of labeled disofenin, a member of the HIDA family of radiopharmaceuticals. In this study, we perform experiments which document that the simulation process itself is accurate. We then calculate the MTT under a variety of experimental conditions involving progressive hepatic ischemia/reperfusion injury and correlate these results with the results of simultaneously performed BSP determinations and hepatic histology. The experimental group with the most pronounced histologic findings (necrosis, vacuolization, disorganization of hepatic cords) also have the most prolonged MTT and BSP half-life. However, both quantitative imaging and BSP testing are able to identify milder degrees of hepatic ischemic injury not reflected in the histologic evaluation. Quantitative imaging with deconvolutional analysis is a technique easily adaptable to the standard nuclear medicine minicomputer. It provides rapid results and appears to be a sensitive monitor of hepatic functional disturbances resulting from ischemia and reperfusion.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26699/1/0000247.pd

Novel functional insights into ischemic stroke biology provided by the first genome-wide association study of stroke in indigenous Africans

\ua9 The Author(s) 2024. Background: African ancestry populations have the highest burden of stroke worldwide, yet the genetic basis of stroke in these populations is obscure. The Stroke Investigative Research and Educational Network (SIREN) is a multicenter study involving 16 sites in West Africa. We conducted the first-ever genome-wide association study (GWAS) of stroke in indigenous Africans. Methods: Cases were consecutively recruited consenting adults (aged > 18 years) with neuroimaging-confirmed ischemic stroke. Stroke-free controls were ascertained using a locally validated Questionnaire for Verifying Stroke-Free Status. DNA genotyping with the H3Africa array was performed, and following initial quality control, GWAS datasets were imputed into the NIH Trans-Omics for Precision Medicine (TOPMed) release2 from BioData Catalyst. Furthermore, we performed fine-mapping, trans-ethnic meta-analysis, and in silico functional characterization to identify likely causal variants with a functional interpretation. Results: We observed genome-wide significant (P-value < 5.0E−8) SNPs associations near AADACL2 and miRNA (MIR5186) genes in chromosome 3 after adjusting for hypertension, diabetes, dyslipidemia, and cardiac status in the base model as covariates. SNPs near the miRNA (MIR4458) gene in chromosome 5 were also associated with stroke (P-value < 1.0E−6). The putative genes near AADACL2, MIR5186, and MIR4458 genes were protective and novel. SNPs associations with stroke in chromosome 2 were more than 77 kb from the closest gene LINC01854 and SNPs in chromosome 7 were more than 116 kb to the closest gene LINC01446 (P-value < 1.0E−6). In addition, we observed SNPs in genes STXBP5-AS1 (chromosome 6), GALTN9 (chromosome 12), FANCA (chromosome 16), and DLGAP1 (chromosome 18) (P-value < 1.0E−6). Both genomic regions near genes AADACL2 and MIR4458 remained significant following fine mapping. Conclusions: Our findings identify potential roles of regulatory miRNA, intergenic non-coding DNA, and intronic non-coding RNA in the biology of ischemic stroke. These findings reveal new molecular targets that promise to help close the current gaps in accurate African ancestry-based genetic stroke’s risk prediction and development of new targeted interventions to prevent or treat stroke

TRANSCENDS: A Career Development Program for Underrepresented in Medicine Scholars in Academic Neurology.

BackgroundThe Training in Research for Academic Neurologists to Sustain Careers and Enhance the Numbers of Diverse Scholars (TRANSCENDS) program is a career advancement opportunity for individuals underrepresented in biomedical research, funded by the National Institute and Neurological Disorders and Stroke; and American Academy of Neurology (AAN).ObjectiveTo report on qualitative and quantitative outcomes in TRANSCENDS.DesignEarly career individuals (neurology fellows and junior faculty) from groups underrepresented in medicine were competitively selected from a national pool of applicants (2016-2019). TRANSCENDS activities comprised an online Clinical Research degree program, monthly webinars, AAN meeting activities, and mentoring. Participants were surveyed during and after completion of TRANSCENDS to evaluate program components.OutcomesOf 23 accepted scholars (comprising four successive cohorts), 56% were women; 61% Hispanic/Latinx, 30% Black/African American, 30% assistant professors. To date, 48% have graduated the TRANSCENDS program and participants have published 180 peer-reviewed articles. Mentees' feedback noted that professional skills development (i.e., manuscript and grant writing), networking opportunities, and mentoring were the most beneficial elements of the program. Stated opportunities for improvement included: incorporating a mentor-the-mentor workshop, providing more transitional support for mentees in the next stage of their careers, and requiring mentees to provide quarterly reports.ConclusionsTRANSCENDS is a feasible program for supporting underrepresented in medicine neurologists towards careers in research and faculty academic appointments attained thus far have been sustained. While longer term outcomes and process enhancements are warranted, programs like this may help increase the numbers of diverse academic neurologists, and further drive neurological innovation

TRANSCENDS: A Career Development Program for Underrepresented in Medicine Scholars in Academic Neurology.

BackgroundThe Training in Research for Academic Neurologists to Sustain Careers and Enhance the Numbers of Diverse Scholars (TRANSCENDS) program is a career advancement opportunity for individuals underrepresented in biomedical research, funded by the National Institute and Neurological Disorders and Stroke; and American Academy of Neurology (AAN).ObjectiveTo report on qualitative and quantitative outcomes in TRANSCENDS.DesignEarly career individuals (neurology fellows and junior faculty) from groups underrepresented in medicine were competitively selected from a national pool of applicants (2016-2019). TRANSCENDS activities comprised an online Clinical Research degree program, monthly webinars, AAN meeting activities, and mentoring. Participants were surveyed during and after completion of TRANSCENDS to evaluate program components.OutcomesOf 23 accepted scholars (comprising four successive cohorts), 56% were women; 61% Hispanic/Latinx, 30% Black/African American, 30% assistant professors. To date, 48% have graduated the TRANSCENDS program and participants have published 180 peer-reviewed articles. Mentees' feedback noted that professional skills development (i.e., manuscript and grant writing), networking opportunities, and mentoring were the most beneficial elements of the program. Stated opportunities for improvement included: incorporating a mentor-the-mentor workshop, providing more transitional support for mentees in the next stage of their careers, and requiring mentees to provide quarterly reports.ConclusionsTRANSCENDS is a feasible program for supporting underrepresented in medicine neurologists towards careers in research and faculty academic appointments attained thus far have been sustained. While longer term outcomes and process enhancements are warranted, programs like this may help increase the numbers of diverse academic neurologists, and further drive neurological innovation