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European Space Agency’s Mars Express (MEX) has been orbiting Mars for 20 years and its instruments have provided a plethora of observations of atmospheric dust and clouds. These observations have been analysed to produce many unique views of the processes leading to dust lifting and cloud formation, and a full picture of the climatologies of dust and clouds has emerged. Moreover, the orbit of MEX enables viewing the planet at many local times, giving a unique access to the diurnal variations of the atmosphere. This article provides an overview of the observations of dust and clouds on Mars by MEX, complemented by the Trace Gas Orbiter that has been accompanying MEX on orbit for some years.

The oxygen emission at 557.7 nm is a ubiquitous component of the spectrum of the terrestrial polar aurora and the reason for its usual green colour 1 . It is also observed as a thin layer of glow surrounding the Earth near 90 km altitude in the dayside atmosphere 2 , 3 but it has so far eluded detection in other planets. Here we report dayglow observations of the green line outside the Earth. They have been performed with the Nadir and Occultation for Mars Discovery ultraviolet and visible spectrometer instrument on board the European Space Agency’s ExoMars Trace Gas Orbiter. Using a special observation mode, scans of the dayside limb provide the altitude distribution of the intensity of the 557.7 nm line and its variability. Two intensity peaks are observed near 80 and 120 km altitude, corresponding to photodissociation of CO 2 by solar Lyman α and extreme ultraviolet radiation, respectively. A weaker emission, originating from the same upper level of the oxygen atom, is observed in the near ultraviolet at 297.2 nm. These simultaneous measurements of both oxygen lines make it possible to directly derive a ratio of 16.5 between the visible and ultraviolet emissions, and thereby clarify a controversy between discordant ab initio calculations and atmospheric measurements that has persisted despite multiple efforts. This ratio is considered a standard for measurements connecting the ultraviolet and visible spectral regions. This result has consequences for the study of auroral and airglow processes and for spectral calibration. The oxygen emission at 557.7 nm, responsible for the green colour of auroras on Earth, is present in two layers at 80 and 120 km altitude on the dayside atmosphere of Mars. Simultaneous observations of the oxygen both in this visible line and in the ultraviolet could also constrain the elusive visible/ultraviolet intensity ratio of the auroral emission to a value of 16.5.

The NOMAD‐UVIS instrument on board the ExoMars Trace Gas Orbiter has been investigating the Martian atmosphere with the occultation technique since April 2018. Here, we analyze almost two Mars Years of ozone vertical distributions acquired at the day‐night terminator. The ozone retrievals proved more difficult than expected due to spurious detections of ozone caused by instrumental effects, high dust content, and very low values of ozone. This led us to compare the results from three different retrieval approaches: (a) an onion peeling method, (b) a full occultation Optimal Estimation Method, and (c) a direct onion peeling method. The three methods produce consistently similar results, especially where ozone densities are higher. The main challenge was to find reliable criteria to exclude spurious detections of O3, and we finally adopted two criteria for filtering: (a) a detection limit, and (b) the Δχ2 criterion. Both criteria exclude spurious O3 values especially near the perihelion (180° < Ls < 340°), where up to 98% of ozone detections are filtered out, in agreement with general circulation models, that expect very low values of ozone in this season. Our agrees well with published analysis of the NOMAD‐UVIS data set, as we confirm the main features observed previously, that is, the high‐altitude ozone peak around 40 km at high latitudes. The filtering approaches are in good agreement with those implemented for the SPICAM/MEx observations and underline the need to evaluate carefully the quality of ozone retrievals in occultations. Key Points We compare three different retrieval codes and different criteria to filter spurious detection of ozone on Mars The filtering criteria demonstrate the ozone detection in perihelion season is mostly spurious in both years The three retrieval methods produce consistent results with a maximum percentage difference of ∼30% for large ozone densities below 50 km

On Mars, atomic oxygen controls the carbon dioxide radiative cooling of the upper atmosphere and the presence of an ozone layer near the poles. To remotely probe meridional transport of O atoms from the summer to the winter hemisphere and the descending flow in the winter polar regions, the O 2 Herzberg II atmospheric emission could be used as a proxy. This emission is quite weak on Earth’s nightside, but it is prominent in the Venus night airglow, and it has not previously been observed on Mars. Here we report the limb detection of the O 2 Herzberg II visible bands in the Mars nightglow with the NOMAD ultraviolet–visible spectrometer onboard the European Space Agency’s Trace Gas Orbiter. The emission layer reaches up to hundreds of kilorayleighs in the limb viewing geometry. It is mainly located between 40 km and 60 km at high latitudes during the winter season, consistent with three-body recombination of oxygen atoms. This O 2 nightglow should be observable from a Martian orbiter as well as from the Martian surface with the naked eye under clear sky conditions. These observations pave the way to future global observations of the Martian atmospheric circulation with simpler lower-cost instrumentation. ESA’s Trace Gas Orbiter reveals that the winter night sky on Mars emits visible light between 50 km and 70 km altitude in the polar regions. This nightglow should be observable with simple space camera systems and the naked eyes of future Mars astronauts.

In 1988, when this study was planned, the recommendation of the Centers for Disease Control and Prevention for the treatment of known or suspected tuberculosis in patients with human immunodeficiency virus (HIV) infection was that at least three drugs (isoniazid, rifampin, and pyrazinamide) should be used during the first two months, with the addition of ethambutol in cases of disseminated disease or suspected resistance to isoniazid. Treatment for nine months was recommended, or for at least six months after conversion to a positive culture, although it was recognized that the optimal duration of therapy was unknown. 1 There was no specific . . .

Tuberculosis (TB) is the most common opportunistic infection in African patients who die from AIDS, yet the stage of immunodeficiency at which TB develops is uncertain. We studied the immune status of HIV-infected outpatients with pulmonary TB in relation to their clinical presentation in a cross-sectional study of 216 HIV-seropositive and 146 HIV-seronegative ambulatory incident cases of smear-positive and culture-positive pulmonary TB in Kinshasa, Zaire. HIV-seropositive and seronegative patients had median CD4 lymphocyte counts of 316·5/μL and 830·5/μL, respectively. Of the HIV-seropositive patients, 32 9% had less than 200 CD4 lymphocytes/μL, 37% between 200 and 499, and 30·1% 500 or more. Clinical AIDS, as defined by the WHO clinical case-definition or a modified version, was of similar limited use as a predictor of immunodeficiency. Among HIV-seropositive patients, oral candidosis, lymphopenia, a negative tuberculin purified protein derivative test, and cutaneous anergy were strongly associated with CD4 counts of less than 200/μL, and seemed to be better markers of immune dysfunction. We conclude that pulmonary TB develops across a broad spectrum of HIV-induced immunodeficiency and that a diagnosis of pulmonary TB is of limited use as a marker of stage of HIV disease in African HIV-infected outpatients.

This work aims to select crisphead lettuce (Lactuca sativa L) genotypes superior in production, stability, and adaptability using a mixed model method: restricted maximum likelihood/best linear unbiased prediction. Ten genotypes were grown in different municipalities of the State of São Paulo, Brazil, and seasons of the year, resulting in twelve different environments. The experiment has a randomized complete block design with four repetitions. Genotypes comprise eight breeding lines and two commercial cultivars, Vanda and Vera. The evaluated traits include total production in g/plant, commercial production in g/plant, and numbers of leaves/plant. Analysis of joint deviance indicated that the genotypes responded differently to the environments evaluated. The crisphead lettuce breeding lines that were most productive, stable, and adapted to the twelve lettuce-growing environments, even outperforming the commercial Vanda and Vera cultivars, were lines L8, L2, and L6. El objetivo de este trabajo fue seleccionar genotipos superiores de lechuga crespa (Lactuca sativa L) en términos de producción, estabilidad y adaptabilidad, cultivados en diferentes municipios y estaciones del año en el Estado de São Paulo, Brasil, mediante la metodología de modelos mixtos: máxima probabilidad residual o restringida/mejor predicción lineal no sesgada. El diseño experimental utilizado fue el de bloques completos al azar con cuatro repeticiones y diez genotipos compuestos de ocho líneas y los cultivares comerciales Vanda y Vera, que se plantaron en doce ambientes diferentes. Los caracteres evaluados fueron producción total en g/planta, producción comercial en g/planta y número de hojas/planta. El análisis de desviación conjunta indicó que los genotipos presentaron respuestas diferentes en los diferentes ambientes evaluados. Las líneas de lechuga crespa más productivas, estables y adaptadas a los doce ambientes de cultivo de lechuga que superaron a los cultivares comerciales Vanda y Vera fueron: L8, L2 y L6.

Generating complex natural-looking movements is desirable in a variety of human-robot interaction scenarios, but remains a task that is challenging to perform in real-time. In this presentation, we describe a generative system for sequencing natural movements for robotic manipulators. Based on the sequencing of movement primitives, the system is developed to generate natural-looking trajectories while minimizing computational time. This allows for the reproduction of natural movements in an environment with time constraints. We sequence movement primitives, expressed using the minimum jerk model, so as to express the various optimization problems into a unique and simpler optimization problem. The system thus allows for the generation of a new, more complex trajectory with a natural looking appearance. The optimization problem is solved in a relatively short amount of time and can be solved in real time in some cases. The natural appearance of the resulting trajectories is studied and compared to other techniques. The final motion does not exactly reproduce the primitives that it is made of; it depends on the movements that occur before and after it. This mimics the natural behaviour of a human that never reproduces the exact same movement twice. The control has been adapted to two different industrial robots so that it can suit the available control mode of such robots. Three applications are presented: the first reproducing human writing with a robotic manipulator. The second allowing to sequence motion recorded using a motion capture device. The last application consists of a choreography of a robot waving a flag in synchronisation with the beat of a music.

Combretum leprosum Mart. -Combretaceae es un arbusto utilizado en la medicina popular del noreste de Brasil como antiulceroso, antihemorrágica y antinociceptiva. En este estudio se desarrolló un modelo para el cálculo de área foliar de Combretum leprosum usando mediciones lineales de longitud (C) y ancho máximo (L) de la hoja. Se recolectaron 200 láminas de hojas de una población de C. leprosum nativo en un área de conservación de la Caatinga en el campus de la Universidad Federal Rural de la Semi árido en Mossoro, Rio Grande do Norte. Las hojas se obtuvieron de árboles adultos y el área foliar se midió utilizando un integrador (LI-3100, LI-COR). El análisis de regresión se hizo con el programa SAEG. Para estimar el área foliar de C. leprosum se puede utilizar la ecuación lineal simple de regresión A = 0.7103 x (C x L), que es equivalente a tomar 71.03% de los productos de la longitud a lo largo de la nervadura central y el ancho máximo, con un coeficiente de determinación de 0.952617.