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NASA’s Perseverance rover’s Mars Environmental Dynamics Analyzer is collecting data at Jezero crater, characterizing the physical processes in the lowest layer of the Martian atmosphere. Here we present measurements from the instrument’s first 250 sols of operation, revealing a spatially and temporally variable meteorology at Jezero. We find that temperature measurements at four heights capture the response of the atmospheric surface layer to multiple phenomena. We observe the transition from a stable night-time thermal inversion to a daytime, highly turbulent convective regime, with large vertical thermal gradients. Measurement of multiple daily optical depths suggests aerosol concentrations are higher in the morning than in the afternoon. Measured wind patterns are driven mainly by local topography, with a small contribution from regional winds. Daily and seasonal variability of relative humidity shows a complex hydrologic cycle. These observations suggest that changes in some local surface properties, such as surface albedo and thermal inertia, play an influential role. On a larger scale, surface pressure measurements show typical signatures of gravity waves and baroclinic eddies in a part of the seasonal cycle previously characterized as low wave activity. These observations, both combined and simultaneous, unveil the diversity of processes driving change on today’s Martian surface at Jezero crater.

To further establish the role of oxidative stress in the pathogenesis of acute bronchial asthma, we investigated the effects of platelet-activating factor (PAF) challenge on systemic oxidant-antioxidant balance in 12 asthmatic patients (age, 25+/-3[sem] yr; FEV"1, 95+/-10% predicted), using a double blinded, controlled with Lyso-PAF (L-PAF), cross-over design. Respiratory system resistance (Rrs), arterial blood gases, peripheral blood neutrophils and oxidant-antioxidant balance, including thiobarbituric acid (TBA)-malondialdehyde (MDA) adducts, protein sulphydryls and Trolox equivalent antioxidant capacity (TEAC), were assessed at baseline and 5, 15 and 45min after PAF and L-PAF (18@mg each) bronchoprovocation. Urinary leukotriene E"4 (uLTE"4) elimination was measured 120min after challenge. Compared with baseline, as expected, PAF increased significantly Rrs and AaPO"2 and decreased PaO"2 and peripheral blood neutrophils along with a rebound neutrophilia and increased uLTE"4. By contrast, markers of systemic oxidative stress remained unaltered throughout the study. Unlike PAF, L-PAF-induced changes were negligible. We conclude that there is no systemic oxidant-antioxidant imbalance during acute bronchoconstriction induced by PAF in these patients with mild asthma.

Reference values for some haematological and plasma chemical values in four species of clinically normal adult flamingos were established for use in avian medicine. The following variables were studied in rosy, greater, Chilean and lesser flamingos: haematocrit, haemoglobin concentration, erythrocyte and leucocyte counts, haematimetric indices, erythrocyte dimensions, glucose, urea, uric acid, cholesterol, creatinine, total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatinine, phosphokinase, lactic dehydrogenase, total phosphorus, chloride, total plasma protein, albumin, globulins, albumin-globulin ratio, sodium, potassium, calcium, magnesium and osmolality.

Erythrocyte osmotic fragility in six species of wild artiodactylid mammals was determined. An inverse relationship was found between erythrocyte dimensions (mean cell diameter and mean cell volume) and osmotic resistance measured as percentage haemolysis in a series of hypotonic solutions. Serum osmolality, under physiological conditions, presents an inverse relationship with erythrocyte size. Possible mechanisms for these findings and also adaptive implications are discussed.

(Abstracted from Human Reprod2018;33:745–756)Chromosomal aneuploidy is common. It occurs in 20% to 80% of human embryos.

Erythrocyte osmotic fragility and plasma ionic composition were studied in rats subjected to acute hypothermia. A decrease in osmotic fragility and a significant increase in plasma magnesium and total phosphorus were observed in blood from hypothermic rats in relation to control. A decrease in erythrocyte osmotic fragility from hypothermic animals was observed when the test was performed at 37°C, whereas osmotic fragility was unaltered if the test was carried out at body temperature. This could be interpreted as an adaptative response to counteract the opposite effect on erythrocyte osmotic fragility observed at low temperature ‘in vitro’.