Infrared Detector Activities at NASA Langley Research Center

Infrared detector development and characterization at NASA Langley Research Center will be reviewed. These detectors were intended for ground, airborne, and space borne remote sensing applications. Discussion will be focused on recently developed single-element infrared detector and future development of near-infrared focal plane arrays (FPA). The FPA will be applied to next generation space-based instruments. These activities are based on phototransistor and avalanche photodiode technologies, which offer high internal gain and relatively low noise-equivalent-power. These novel devices will improve the sensitivity of active remote sensing instruments while eliminating the need for a high power laser transmitter

Mars Atmospheric Characterization Using Advanced 2-Micron Orbiting Lidar

Mars atmospheric characterization is critical for exploring the planet. Future Mars missions require landing massive payloads to the surface with high accuracy. The accuracy of entry, descent and landing (EDL) of a payload is a major technical challenge for future Mars missions. Mars EDL depends on atmospheric conditions such as density, wind and dust as well as surface topography. A Mars orbiting 2-micron lidar system is presented in this paper. This advanced lidar is capable of measuring atmospheric pressure and temperature profiles using the most abundant atmospheric carbon dioxide (CO2) on Mars. In addition Martian winds and surface altimetry can be mapped, independent of background radiation or geographical location. This orbiting lidar is a valuable tool for developing EDL models for future Mars missions

Two-micron Detector Development using Sb-based Material Systems

NASA Langley Research Center (LaRC), in partnership with the University of Delaware (UD), developed AlGaAsSb/InGaAsSb custom-designed phototransistors in the 0.6-2.5 micron wavelength range for applications to laser remote sensing. The phototransistor s performance greatly exceeds the previously reported results at this wavelength range in the literature. The performances of the custom-designed phototransistor, such as responsivity, detectivity, and gain, are improved significantly as compared to the previously published detectors as well as commercial detectors. Detection in the 0.6- to 2.5- micron broadband with a single phototransistor will result in reduction or elimination of heavy and complex optical components now required for multiple wavelength detection in atmospheric remote sensors resulting in smaller, lighter, simpler instruments with higher performance. This high performance broadband phototransistor will eliminate the need for high power laser for active remote sensing and also the Si (1.0- micron cutoff) and InGaAs (extended 2.3- micron cutoff) detectors. The developed broadband phototransistor will be applicable for the next generation of space-based Earth observations and other planetary instruments for active and passive remote sensing with substantial reduction in size, complexity, and weight to measure water vapor, methane, and carbon dioxide in planetary atmospheres as well as aerosol, cloud, water vapor, O2, CO, and CO2 for a broad range of applications to Earth and Space Science Missions under Science Mission Directorate (SMD) research programs

Column CO2 Measurement From an Airborne Solid-State Double-Pulsed 2-Micron Integrated Path Differential Absorption Lidar

NASA LaRC is developing and integrating a double-Pulsed 2-micron direct detection IPDA lidar for CO2 column measurement from an airborne platform. The presentation will describe the development of the 2-micrometers IPDA lidar system and present the airborne measurement of column CO2 and will compare to in-situ measurement for various ground target of different reflectivity

The Effect of Intermittent Fasting and Caloric Restricted Diet on Diabetic Rats

The present study was aimed to investigate the effect of intermittent fasting and caloric restricted diet (RD) for 8 weeks on diabetic rats. Forty-nine adult male albino rats were divided into two main groups; the first main group was fed only on basal diet and served as negative control group and the second main group: diabetic rats were induced by a single intra-peritoneal injection of freshly prepared STZ (60 mg/kg BW) then divided into 6 subgroups: Subgroup (1) was fed only on basal diet and was served as positive cont. Subgroup (2) was fed on RD only. Subgroups (3, 4) were fed on basal diet and were deprived of food except water from 5 p.m. to 8 a.m. twice a week and every other day, respectively. Subgroups (5, 6): were fed on RD and intermittent fasting twice a week and every other day, respectively. The results indicated that RD and intermittent fasting significantly decreased the final body weight, feed intake and body weight gain % values as compared to the positive control rats. Diabetic treated rats had significant increase (p<0.05) in insulin concentration and lower glucose levels as well as an improvement in liver functions and lipid profile as compared to the positive control group. Conclusion: the findings suggest that intermittent fasting and caloric restricted diet could have a potential role in managing diabetes

The global burden of injury: Incidence, mortality, disability-adjusted life years and time trends from the global burden of disease study 2013

Background The Global Burden of Diseases (GBD), Injuries, and Risk Factors study used the disabilityadjusted life year (DALY) to quantify the burden of diseases, injuries, and risk factors. This paper provides an overview of injury estimates from the 2013 update of GBD, with detailed information on incidence, mortality, DALYs and rates of change from 1990 to 2013 for 26 causes of injury, globally, by region and by country. Methods Injury mortality was estimated using the extensive GBD mortality database, corrections for illdefined cause of death and the cause of death ensemble modelling tool. Morbidity estimation was based on inpatient and outpatient data sets, 26 cause-of-injury and 47 nature-of-injury categories, and seven follow-up studies with patient-reported long-term outcome measures. Results In 2013, 973 million (uncertainty interval (UI) 942 to 993) people sustained injuries that warranted some type of healthcare and 4.8 million (UI 4.5 to 5.1) people died from injuries. Between 1990 and 2013 the global age-standardised injury DALY rate decreased by 31% (UI 26% to 35%). The rate of decline in DALY rates was significant for 22 cause-of-injury categories, including all the major injuries. Conclusions Injuries continue to be an important cause of morbidity and mortality in the developed and developing world. The decline in rates for almost all injuries is so prominent that it warrants a general statement that the world is becoming a safer place to live in. However, the patterns vary widely by cause, age, sex, region and time and there are still large improvements that need to be made

Status of ablation of cardiac arrhythmias in Lebanon

Objectives: The 2017 European Heart Rhythm Association (EHRA) White Book was published with interventional electrophysiology data on ESC member countries. Lebanon, an ESC member country, did not have data on cardiac ablation. Hence, there was an unmet need to have cardiac ablation estimate in Lebanon. Methods: Data from companies providing support for cardiac ablation in Lebanon was collected for the year 2017. Results: In 2017, the number of catheter ablations performed was close to 350. This is around 70 per million of Lebanese. There has been a significant increase, over 50%, in the 2010-2017 period: 50 to 60 ablation procedures were performed annually in 2010 (most of them for supraventricular tachycardias) and this increased to around 100 per year in 2013. Conclusion: Cardiac ablation procedures have increased over the last several years in Lebanon in parallel with the number of cardiac electrophysiologists. It is important to have a national registry of cardiac ablations in Lebanon which will require financial support for its maintenance. © 2019 Lebanese Order of Physicians. All rights reserved

Cardiac involvement in beta-thalassaemia: current treatment strategies

Despite the advances in the management of thalassemia major, heart disease remains the leading cause of mortality in patients afflicted with this disorder. Cardiac involvement in thalassemia encompasses a spectrum of disorders including myocardial dysfunction, arrhythmias, pulmonary hypertension, and peripheral vascular disease. Although cardiac siderosis (accumulation of iron in cardiac myocytes) as a consequence of repeated blood transfusions is deemed to be the main etiologic factor for myocardial dysfunction in transfusion-dependent patients, the significance of other pathophysiologic mechanisms is being increasingly recognized especially in non-transfusion dependent patients. Management of cardiac complications in thalassemia major hinges on the treatment of the underlying pathophysiology, which often is unmitigated iron overload. The prevalence and predictors of cardiac complications in ‘ex-thalassaemics’ [thalassaemic patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) is unknown at present. In this review, we look at the pathogenesis of cardiac involvement in patients with beta-thalassemia major, the advances in the management of these patients and the future prospects. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group

Cardiac implantable electronic devices in Lebanon

Objectives: The 2017 European Heart Rhythm Association (EHRA) White Book was published with cardiac implantable electronic device (CIED) data on European Society of Cardiology (ESC) member countries. Three countries (Lebanon, Libya and Syria) of the 56 ESC member countries did not have data. Hence, there was an unmet need to have CIED data estimate in Lebanon. Methods: Data from companies providing CIEDs in Lebanon was collected to have trends on CIED implants in Lebanon from the beginning of 2013 till the end of 2017. Results: In 2017, the total number of CIED implants was 1656: 983 (59.4%) were pacemakers and 673 (40.6%) were ICDs. Most CIED implants are dual chamber pacemakers. There has been a rise in the implantation of ICDs in Lebanon from 2013 till 2017. For instance, in 2013 the prevalence of CRT-D, dual chamber ICD, and single chamber ICD were 214, 64, and 268. In 2017, the prevalence of the different types of ICD became 243, 75, and 355. Conclusion: CIED implants have increased over the last several years in Lebanon in parallel with the number of cardiac electrophysiologists. It is important to have a national registry of CIED implants in Lebanon which will require financial support for its maintenance. © 2019 Lebanese Order of Physicians. All rights reserved

Digital thermography and vascular involvement in β-thalassemia intermedia

Beta-thalassemia intermedia (β-TI) is associated with vascular dysfunction. We used digital thermal monitoring (DTM), a non-invasive tool that evaluates vascular function based on changes in fingertip temperature during and after cuff occlusion on β-TI patients. Thirty-three patients (18 years and older) were recruited in this study and divided into 3 groups: thalassemia, anemic controls, and healthy controls. Exclusion criteria included factors that are known to be associated with vascular damage. Patients underwent DTM and results were extracted as vascular reactivity index (VRI), a measure of how well the circulatory system responds to stimuli that require adjustments of blood flow. One-way analysis of variance (ANOVA) was used to test the mean difference in VRI between the 3 groups. A multiple linear regression was also carried out with VRI as the outcome of interest and a function of covariates that were thought to be of clinical relevance to VRI. The frequency, mean VRI ± standard error (SE) for the thalassemic group were (N = 16), mean = 2.243 ± 0.111; for anemic controls (N = 9), mean = 2.374 ± 0.162; and for the controls (N = 8), mean = 2.338 ± 0.092. ANOVA test indicated a non-significant difference in mean VRI between the three groups (P value = 0.731). Multiple linear regression couldn’t detect any significant association between VRI and any of the predictors including the groups. Our study did not show a significant difference in VRI between the 3 study groups. Prospective studies of larger sample size are warranted to establish DTM as a possible non-invasive tool used to evaluate vascular function in β-TI patients. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature