A genetic-based prognostic method for aerospace electromechanical actuators

Prior awareness of impending failures of primary flight command electromechanical actuators (EMAs) utilizing prognostic algorithms can be extremely useful. Indeed, early detection of the degradation pattern might signal the need to replace the servomechanism before the failure manifests itself. Furthermore, such algorithms frequently use a model-based approach based on a direct comparison of the real (High Fidelity) and monitor (Low Fidelity) systems to discover fault characteristics via optimization methods. The monitor model enables the gathering of accurate and exact data while requiring a minimal amount of processing. This work describes a novel simplified monitor model that accurately reproduces the dynamic response of a typical aerospace EMA. The task of fault detection and identification is carried out by comparing the output signal of the reference system (the high fidelity model) with that acquired from the monitor model. The Genetic Algorithm is then used to optimize the matching between the two signals by iteratively modifying the fault parameters, getting the global minimum of a quadratic error function. Once this is found, the optimization parameters are connected with the assumed progressive failures to assess the system's health. The high-fidelity reference model examined in this study is previously conceptualized, developed, implemented in MATLAB-Simulink and finally experimentally confirmed

Analyzing the determinant characteristics for a good performance at enade brazilian exam stratified by teaching modality: face-to-face versus online

The National Student Performance Exam (ENADE) annually evaluates different Brazilian higher education courses. This exam considers both face-to-face and distance learning courses. Distance learning is growing increasingly, especially during the coronavirus (COVID-19) pandemic. This study applies different techniques for selecting ENADE 2018 database characteristics, like information gain, gain rate, symmetric uncertainty, Pearson correlation, and relief F. The objective of the work is to discover which personal and socioeconomic characteristics are decisive for the student's performance at ENADE, whether the student is in the context of Distance Education or face-to-face. It can be concluded, among other results, that: the father's level of education directly influences performance; the higher the income, the better the performance; and white students have better performance than black and brown-skinned ones. Thus, the results obtained in this study may initiate analyzes of public policies towards improving performance at ENADE.This study was supported by CNPq (305805/2021-5) and PNPD/CAPES (464880/2019-00)

High gear ratio mechanical transmissions for actuators: Simplified models for efficiency under opposing and aiding loads

Planetary gear drives are widely employed in electrical and hydraulic actuation systems, to adapt a high speed, low torque motor to a low speed, high torque user, within strict weight and volume constraints. During the early design phases of these devices, accurate yet simple simulation models are required to evaluate the performance of a given configuration of the device. Similar models are also useful within diagnostic and health monitoring analyses of existing machines, as a discrepancy between the actual behaviour of the physical system and that predicted by its digital twin may be the effect of a damage. This work compares different models available in literature for the efficiency of high gear ratio mechanical transmissions; the models are applied to multiple arrangements common for planetary drives, and the results in form of an efficiency map for the transmissions are compared and discussed. The simulations provide different levels of detail, and require different levels of knowledge about the specific architecture of the system. All of them are able to deal with dry friction; additionally, the different behaviour of the transmission under the effect loads aligned in the same direction of speed or in the opposite one is accounted for

FAbry STabilization indEX (FASTEX) : an innovative tool for the assessment of clinical stabilization in Fabry disease

Two disease severity scoring systems, the Mainz Severity Score Index (MSSI) and Fabry Disease Severity Scoring System (DS3), have been validated for quantifying the disease burden of Fabry disease. We aimed to develop a dynamic mathematical model [the FASTEX (FAbry STabilization indEX)] to assess the clinical stability. A multidisciplinary panel of experts in Fabry disease first defined a novel score of severity [raw score (RS)] based on three domains with a small number items in each domain (nervous system domain: pain, cerebrovascular events; renal domain: proteinuria, glomerular filtration rate; cardiac domain: echocardiography parameters, electrocardiograph parameters and New York Heart Association class) and evaluated the clinical stability over time. The RS was tested in 28 patients (15 males, 13 females) with the classic form of Fabry disease. There was good statistical correlation between the newly established RS and a weighted score (WS), with DS3 and MSSI (R (2) = 0.914, 0.949, 0.910 and 0.938, respectively). In order to refine the RS further, a WS, which was expressed as a percentage value, was calculated. This was based on the relative clinical significance of each item within the domain with the panel agreeing on the attribution of a different weight of clinical damage to a specific organ system. To test the variation of the clinical burden over time, the RS was repeated after 1 year. The panel agreed on a cut-off of a 20% change from baseline as the clinical WS to define clinical stability. The FASTEX model showed good correlation with the clinical assessment and with clinical variation over time in all patients

COMPARATIVE TOXICITY STUDY OF CHLOROQUINE AND HYDROXYCHLOROQUINE ON ADULT ALBINO RATS

Expanded use of Chloroquine and hydroxychloroquine drugs for non-malarial disease entities has resulted in prolonged duration of therapy and higher daily dosages leading to cumulative doses greater than those used in antimalarial therapy. The aim of the study is to evaluate and compare the toxic effects of chloroquine and hydroxychloroquine on different organs of albino rats. The study was conducted on 60 normal albino rats divided into 3 groups, the 1st group is the control group that received only distilled water, the 2nd and the 3rd group were given a single daily oral doses equivalent to 1/10th of LD50 chloroquine and hydroxychloroquine respectively. Assessment of liver and kidney functions, and histopathological changes in liver, kidney, and heart in different groups was done. The chloroquine treated group showed significant elevation of serum glutamic pyruvic transaminase (SGPT), serum glutamic oxaloacetic transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin (TB), serum creatinine-urea (Cr-U), Creatine Kinase-MB, C-reactive protein and Malonic dialdehyde levels as compared to control and hydroxychloroquine treated group. The histopathological evaluation showed marked hydropic degeneragtion, vascular congestion, interstitial hemorrhage, and necrosis in the liver, kidney and heart of chloroquine treated group, while hydroxychloroquine treated group showed mild congestion and slight cellular degeneration. Thus, hydroxychloroquine is less toxic and physicians should prescribe it better than chloroquine. Chloroquine if prescribed for therapeutic uses should be taken for short periods

Study of Packaging and Installation of FBG Sensors for Monitoring of Aircraft Systems

Next generation aircraft systems will feature an ever increasing complexity. In this context, advanced health monitoring strategies will be required to ensure a high level of operations safety as well as a good reliability. Hence, Prognostics and Health Management (PHM) is emerging as an enabling discipline for future advanced aircraft design and operations, with a particular application to Flight Control System (FCS) monitoring. One of the most critical issues for real-time Fault Detection and Identification (FDI) of aircraft FCS is the availability of actuator load measurements. The aerodynamic load on flight control actuators has a significant influence on their dynamic response, and can easily hide the effect of incipient failure precursors. For this reason, real-time monitoring FDI algorithms relying on the comparison between the actual system response and that of a digital twin require either a measure or an estimation of aerodynamic loads. Usually, this quantity is not monitored by a dedicated sensor, since it is not required as a feedback signal by most control logics. A dedicated load sensor for PHM with traditional technologies is not easily feasible: for example, a load cell would be mechanically connected in series with the actuator, adding a potential single failure point and affecting the overall system safety; the use of strain gages on the structure is less accurate, and requires several sensors with individual wiring and complex signal conditioning circuitry. Optical strain sensors based on Fiber Bragg Gratings (FBG) allow indirect load measurement combined with real-time structural monitoring, combining an acceptable increase in complexity and costs with a high robustness. In this preliminary study, we installed an FBG monitoring system on a UAV to assess the feasibility of such technology. Measures of structure deflection were correlated to actuator position and IMU data, to estimate aerodynamic loads

COMPARATIVE TOXICITY STUDY OF CHLOROQUINE AND HYDROXYCHLOROQUINE ON ADULT ALBINO RATS

Expanded use of Chloroquine and hydroxychloroquine drugs for non-malarial disease entities has resulted in prolonged duration of therapy and higher daily dosages leading to cumulative doses greater than those used in antimalarial therapy. The aim of the study is to evaluate and compare the toxic effects of chloroquine and hydroxychloroquine on different organs of albino rats. The study was conducted on 60 normal albino rats divided into 3 groups, the 1st group is the control group that received only distilled water, the 2nd and the 3rd group were given a single daily oral doses equivalent to 1/10th of LD50 chloroquine and hydroxychloroquine respectively. Assessment of liver and kidney functions, and histopathological changes in liver, kidney, and heart in different groups was done. The chloroquine treated group showed significant elevation of serum glutamic pyruvic transaminase (SGPT), serum glutamic oxaloacetic transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin (TB), serum creatinine-urea (Cr-U), Creatine Kinase-MB, C-reactive protein and Malonic dialdehyde levels as compared to control and hydroxychloroquine treated group. The histopathological evaluation showed marked hydropic degeneragtion, vascular congestion, interstitial hemorrhage, and necrosis in the liver, kidney and heart of chloroquine treated group, while hydroxychloroquine treated group showed mild congestion and slight cellular degeneration. Thus, hydroxychloroquine is less toxic and physicians should prescribe it better than chloroquine. Chloroquine if prescribed for therapeutic uses should be taken for short periods

Low level wind forecast over the Uruguay River region nearby Gualeguaychú, using a boundary layer model forced by WRF regional operational forecasts

The mesoscale atmospheric boundary layer model –BLM- is used to run daily low level wind field forecasts over the Uruguay River region nearby Gualeguaychú. BLM runs with a horizontal resolution of 1 km, forced by initial and boundary conditions defined from the operational WRF forecasts of the National Meteorological Service of Argentina at 5 km resolution. The low level wind forecast is validated with the observations of three 42-meter tall meteorological towers located on the coast of the Uruguay River, during the period June 2010 to May 2013. Despite the WRF forecast errors propagate and impact somehow the quality of the final forecast, BLM is able to overcome this situation and produce a forecast with smaller error than WRF at two of the three places.Eje: Ciencias de la Atmósfera y los Océanos.Facultad de Ciencias Astronómicas y Geofísica

Epidemiology of Coxiella burnetii infection in Africa: a OneHealth systematic review

Background: Q fever is a common cause of febrile illness and community-acquired pneumonia in resource-limited settings. Coxiella burnetii, the causative pathogen, is transmitted among varied host species, but the epidemiology of the organism in Africa is poorly understood. We conducted a systematic review of C. burnetii epidemiology in Africa from a “One Health” perspective to synthesize the published data and identify knowledge gaps.<p></p> Methods/Principal Findings: We searched nine databases to identify articles relevant to four key aspects of C. burnetii epidemiology in human and animal populations in Africa: infection prevalence; disease incidence; transmission risk factors; and infection control efforts. We identified 929 unique articles, 100 of which remained after full-text review. Of these, 41 articles describing 51 studies qualified for data extraction. Animal seroprevalence studies revealed infection by C. burnetii (≤13%) among cattle except for studies in Western and Middle Africa (18–55%). Small ruminant seroprevalence ranged from 11–33%. Human seroprevalence was <8% with the exception of studies among children and in Egypt (10–32%). Close contact with camels and rural residence were associated with increased seropositivity among humans. C. burnetii infection has been associated with livestock abortion. In human cohort studies, Q fever accounted for 2–9% of febrile illness hospitalizations and 1–3% of infective endocarditis cases. We found no studies of disease incidence estimates or disease control efforts.<p></p> Conclusions/Significance: C. burnetii infection is detected in humans and in a wide range of animal species across Africa, but seroprevalence varies widely by species and location. Risk factors underlying this variability are poorly understood as is the role of C. burnetii in livestock abortion. Q fever consistently accounts for a notable proportion of undifferentiated human febrile illness and infective endocarditis in cohort studies, but incidence estimates are lacking. C. burnetii presents a real yet underappreciated threat to human and animal health throughout Africa.<p></p&gt

Detection of a Cis eQTL Controlling BMCO1 Gene Expression Leads to the Identification of a QTG for Chicken Breast Meat Color

Classical quantitative trait loci (QTL) analysis and gene expression QTL (eQTL) were combined to identify the causal gene (or QTG) underlying a highly significant QTL controlling the variation of breast meat color in a F2 cross between divergent high-growth (HG) and low-growth (LG) chicken lines. Within this meat quality QTL, BCMO1 (Accession number GenBank: AJ271386), encoding the β-carotene 15, 15′-monooxygenase, a key enzyme in the conversion of β-carotene into colorless retinal, was a good functional candidate. Analysis of the abundance of BCMO1 mRNA in breast muscle of the HG x LG F2 population allowed for the identification of a strong cis eQTL. Moreover, reevaluation of the color QTL taking BCMO1 mRNA levels as a covariate indicated that BCMO1 mRNA levels entirely explained the variations in meat color. Two fully-linked single nucleotide polymorphisms (SNP) located within the proximal promoter of BCMO1 gene were identified. Haplotype substitution resulted in a marked difference in BCMO1 promoter activity in vitro. The association study in the F2 population revealed a three-fold difference in BCMO1 expression leading to a difference of 1 standard deviation in yellow color between the homozygous birds at this haplotype. This difference in meat yellow color was fully consistent with the difference in carotenoid content (i.e. lutein and zeaxanthin) evidenced between the two alternative haplotypes. A significant association between the haplotype, the level of BCMO1 expression and the yellow color of the meat was also recovered in an unrelated commercial broiler population. The mutation could be of economic importance for poultry production by making possible a gene-assisted selection for color, a determining aspect of meat quality. Moreover, this natural genetic diversity constitutes a new model for the study of β-carotene metabolism which may act upon diverse biological processes as precursor of the vitamin A