Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation.

Pluto and Eris are icy dwarf planets with nearly identical sizes, comparable densities and similar surface compositions as revealed by spectroscopic studies. Pluto possesses an atmosphere whereas Eris does not; the difference probably arises from their differing distances from the Sun, and explains their different albedos. Makemake is another icy dwarf planet with a spectrum similar to Eris and Pluto, and is currently at a distance to the Sun intermediate between the two. Although Makemake's size (1,420 ± 60 km) and albedo are roughly known, there has been no constraint on its density and there were expectations that it could have a Pluto-like atmosphere. Here we report the results from a stellar occultation by Makemake on 2011 April 23. Our preferred solution that fits the occultation chords corresponds to a body with projected axes of 1,430 ± 9 km (1σ) and 1,502 ± 45 km, implying a V-band geometric albedo p(V) = 0.77 ± 0.03. This albedo is larger than that of Pluto, but smaller than that of Eris. The disappearances and reappearances of the star were abrupt, showing that Makemake has no global Pluto-like atmosphere at an upper limit of 4-12 nanobar (1σ) for the surface pressure, although a localized atmosphere is possible. A density of 1.7 ± 0.3 g cm(-3) is inferred from the data.

The 67P/Churyumov-Gerasimenko observation campaign in support of the Rosetta mission.

We present a summary of the campaign of remote observations that supported the European Space Agency's Rosetta mission. Telescopes across the globe (and in space) followed comet 67P/Churyumov-Gerasimenko from before Rosetta's arrival until nearly the end of the mission in September 2016. These provided essential data for mission planning, large-scale context information for the coma and tails beyond the spacecraft and a way to directly compare 67P with other comets. The observations revealed 67P to be a relatively 'well-behaved' comet, typical of Jupiter family comets and with activity patterns that repeat from orbit to orbit. Comparison between this large collection of telescopic observations and the in situ results from Rosetta will allow us to better understand comet coma chemistry and structure. This work is just beginning as the mission ends-in this paper, we present a summary of the ground-based observations and early results, and point to many questions that will be addressed in future studies.This article is part of the themed issue 'Cometary science after Rosetta'.

Surface changes on comet 67P/Churyumov-Gerasimenko suggest a more active past.

The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2 ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.

Rosetta's comet 67P/Churyumov-Gerasimenko sheds its dusty mantle to reveal its icy nature.

The Rosetta spacecraft has investigated comet 67P/Churyumov-Gerasimenko from large heliocentric distances to its perihelion passage and beyond. We trace the seasonal and diurnal evolution of the colors of the 67P nucleus, finding changes driven by sublimation and recondensation of water ice. The whole nucleus became relatively bluer near perihelion, as increasing activity removed the surface dust, implying that water ice is widespread underneath the surface. We identified large (1500 square meters) ice-rich patches appearing and then vanishing in about 10 days, indicating small-scale heterogeneities on the nucleus. Thin frosts sublimating in a few minutes are observed close to receding shadows, and rapid variations in color are seen on extended areas close to the terminator. These cyclic processes are widespread and lead to continuously, slightly varying surface properties.

The immunoregulatory effects of prolactin in mice are time of day dependent.

The effects of timed administration of PRL on immune activities were investigated in male BALB/c mice. Ten daily injections of PRL (1 mg/kg) were made 0/24, 4, 8, 12, 16, or 20 h after light onset (HALO). On day 11, spleen cells were harvested between 1-3 HALO and cocultured with gamma-irradiated C57BL/6 spleen cells for 5 days, and proliferative responses to alloantigen were assayed (mixed lymphocyte reaction). When given in vivo at 4-12 HALO, PRL strongly stimulated proliferation by more than 2-fold, whereas PRL injections when given at 24 HALO substantially inhibited proliferation and had no effect when given at 16-20 HALO. When endogenous PRL secretion was stimulated for 7 days with injections of domperidone or 5-hydroxytryptophan, the splenocyte response increased by 48% and 64%, respectively, when injections were given at 9-10 HALO, but did not increase when they were given at 23-0 HALO. Inhibition of endogenous PRL secretion for 7 days with bromocriptine (2.5 mg/kg.day) inhibited splenocyte responsiveness by 40% when injected at 9 HALO, but had no effect when administered at 0 HALO. Furthermore, such bromocriptine treatment inhibited T- and B-cell mitogenic responses to Concanavalin-A (by 48%) and lipopolysaccharide (38%) when administered at 10, but not 0, HALO. In a manner similar to mixed lymphocyte reaction responses, daily PRL injections for 10 days at 11 HALO stimulated (40%) the in vivo delayed-type hypersensitivity response to antigen (azobenzenearsonate), whereas injections at 0 HALO were nonstimulatory. Bromocriptine treatment (1.5 mg/kg.day) suppressed the delayed-type hypersensitivity response (43% less than the control value) when administered at 10-12 HALO, but had no effect when administered at light onset. Timed PRL injections for 28 days in adult mice increased (42%) the total thymic cell number when administered at 11 HALO, but had no effect when injected at 0 HALO. Together, these results show that immunocyte responsiveness to PRL is time of day dependent. Thus, these findings support an essential and heretofore unrecognized circadian role in PRL regulation of immunity.

E-type asteroid (2867) Steins as imaged by OSIRIS on board Rosetta.

The European Space Agency's Rosetta mission encountered the main-belt asteroid (2867) Steins while on its way to rendezvous with comet 67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical, spectroscopic, and infrared remote( )imaging system) cameras on board Rosetta show that Steins is an oblate body with an effective spherical diameter of 5.3 kilometers. Its surface does not show color variations. The morphology of Steins is dominated by linear faults and a large 2.1-kilometer-diameter crater near its south pole. Crater counts reveal a distinct lack of small craters. Steins is not solid rock but a rubble pile and has a conical appearance that is probably the result of reshaping due to Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) spin-up. The OSIRIS images constitute direct evidence for the YORP effect on a main-belt asteroid.

Fetal monitoring during air medical transport.

A prior survey of physiologic monitoring practices during maternal air medical transport by helicopter found that cardiotocography is rarely utilized. The authors report their experience with fetal heart-rate monitoring during helicopter transport of high-risk mothers. The technique is as readily applied to the care of the patient in a helicopter as it is in the modern labor and delivery suite. The study found no substantial reasons why such monitoring should not be used in air medical transport.

¿Tiene mi paciente un trastorno delirante? / Does my patient have a delusional disorder?

El trastorno delirante crónico (TDC) se caracteriza por la presencia de ideas delirantes no extrañas, sin alucinaciones ni alteraciones del lenguaje o el pensamiento y que no conllevan deterioro de la personalidad

Chronic delusional disorder (CDD) is characterized by the presence of non-rare delusional ideas, without hallucinations or speech or thought disorders and does not entail personality deterioration

Nódulos pulmonares múltiples asociados a derrame pleural izquierdo como forma de presentación de una tuberculosis pulmonar / Multiple pulmonary nodules associated with left pleural effusion as presentation of pulmonary tuberculosis

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