Less absorbed solar energy and more internal heat for Jupiter.

The radiant energy budget and internal heat are fundamental properties of giant planets, but precise determination of these properties remains a challenge. Here, we report measurements of Jupiter's radiant energy budget and internal heat based on Cassini multi-instrument observations. Our findings reveal that Jupiter's Bond albedo and internal heat, 0.503 ± 0.012 and 7.485 ± 0.160 W m-2 respectively, are significantly larger than 0.343 ± 0.032 and 5.444 ± 0.425 Wm-2, the previous best estimates. The new results help constrain and improve the current evolutionary theories and models for Jupiter. Furthermore, the significant wavelength dependency of Jupiter's albedo implies that the radiant energy budgets and internal heat of the other giant planets in our solar system should be re-examined. Finally, the data sets of Jupiter's characteristics of reflective solar spectral irradiance provide an observational basis for the models of giant exoplanets.

An absolute sodium abundance for a cloud-free 'hot Saturn' exoplanet.

Broad absorption signatures from alkali metals, such as the sodium (Na I) and potassium (K I) resonance doublets, have long been predicted in the optical atmospheric spectra of cloud-free irradiated gas giant exoplanets1-3. However, observations have revealed only the narrow cores of these features rather than the full pressure-broadened profiles4-6. Cloud and haze opacity at the day-night planetary terminator are considered to be responsible for obscuring the absorption-line wings, which hinders constraints on absolute atmospheric abundances7-9. Here we report an optical transmission spectrum for the 'hot Saturn' exoplanet WASP-96b obtained with the Very Large Telescope, which exhibits the complete pressure-broadened profile of the sodium absorption feature. The spectrum is in excellent agreement with cloud-free, solar-abundance models assuming chemical equilibrium. We are able to measure a precise, absolute sodium abundance of logεNa = [Formula: see text], and use it as a proxy for the planet's atmospheric metallicity relative to the solar value (Zp/Zʘ = [Formula: see text]). This result is consistent with the mass-metallicity trend observed for Solar System planets and exoplanets10-12.

ON THE COMPOSITION OF YOUNG, DIRECTLY IMAGED GIANT PLANETS.

The past decade has seen significant progress on the direct detection and characterization of young, self-luminous giant planets at wide orbital separations from their host stars. Some of these planets show evidence for disequilibrium processes like transport-induced quenching in their atmospheres; photochemistry may also be important, despite the large orbital distances. These disequilibrium chemical processes can alter the expected composition, spectral behavior, thermal structure, and cooling history of the planets, and can potentially confuse determinations of bulk elemental ratios, which provide important insights into planet-formation mechanisms. Using a thermo/photochemical kinetics and transport model, we investigate the extent to which disequilibrium chemistry affects the composition and spectra of directly imaged giant exoplanets. Results for specific "young Jupiters" such as HR 8799 b and 51 Eri b are presented, as are general trends as a function of planetary effective temperature, surface gravity, incident ultraviolet flux, and strength of deep atmospheric convection. We find that quenching is very important on young Jupiters, leading to CO/CH4 and N2/NH3 ratios much greater than, and H2O mixing ratios a factor of a few less than, chemical-equilibrium predictions. Photochemistry can also be important on such planets, with CO2 and HCN being key photochemical products. Carbon dioxide becomes a major constituent when stratospheric temperatures are low and recycling of water via the H2 + OH reaction becomes kinetically stifled. Young Jupiters with effective temperatures ≲700 K are in a particularly interesting photochemical regime that differs from both transiting hot Jupiters and our own solar-system giant planets.

Discovery and spectroscopy of the young jovian planet 51 Eri b with the Gemini Planet Imager.

Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption. Modeling of the spectra and photometry yields a luminosity (normalized by the luminosity of the Sun) of 1.6 to 4.0 × 10(-6) and an effective temperature of 600 to 750 kelvin. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold-start" core-accretion process that may have formed Jupiter.

Habitable evaporated cores: transforming mini-Neptunes into super-Earths in the habitable zones of M dwarfs.

We show that photoevaporation of small gaseous exoplanets ("mini-Neptunes") in the habitable zones of M dwarfs can remove several Earth masses of hydrogen and helium from these planets and transform them into potentially habitable worlds. We couple X-ray/extreme ultraviolet (XUV)-driven escape, thermal evolution, tidal evolution, and orbital migration to explore the types of systems that may harbor such "habitable evaporated cores" (HECs). We find that HECs are most likely to form from planets with ∼1 M⊕ solid cores with up to about 50% H/He by mass, though whether or not a given mini-Neptune forms a HEC is highly dependent on the early XUV evolution of the host star. As terrestrial planet formation around M dwarfs by accumulation of local material is likely to form planets that are small and dry, evaporation of small migrating mini-Neptunes could be one of the dominant formation mechanisms for volatile-rich Earths around these stars.

COMPOSITIONAL DIVERSITY IN THE ATMOSPHERES OF HOT NEPTUNES, WITH APPLICATION TO GJ 436b.

Neptune-sized extrasolar planets that orbit relatively close to their host stars - often called "hot Neptunes" - are common within the known population of exoplanets and planetary candidates. Similar to our own Uranus and Neptune, inefficient accretion of nebular gas is expected produce hot Neptunes whose masses are dominated by elements heavier than hydrogen and helium. At high atmospheric metallicities of 10-10,000× solar, hot Neptunes will exhibit an interesting continuum of atmospheric compositions, ranging from more Neptune-like, H2-dominated atmospheres to more Venus-like, CO2-dominated atmospheres. We explore the predicted equilibrium and disequilibrium chemistry of generic hot Neptunes and find that the atmospheric composition varies strongly as a function of temperature and bulk atmospheric properties such as metallicity and the C/O ratio. Relatively exotic H2O, CO, CO2, and even O2-dominated atmospheres are possible for hot Neptunes. We apply our models to the case of GJ 436b, where we find that a CO-rich, CH4-poor atmosphere can be a natural consequence of a very high atmospheric metallicity. From comparisons of our results with Spitzer eclipse data for GJ 436b, we conclude that although the spectral fit from the high-metallicity forward models is not quite as good as the best fit obtained from pure retrieval methods, the atmospheric composition predicted by these forward models is more physically and chemically plausible in terms of the relative abundance of major constituents. High-metallicity atmospheres (orders of magnitude in excess of solar) should therefore be considered as a possibility for GJ 436b and other hot Neptunes.

Restoration of all dystrophin protein interactions by functional domains in trans does not rescue dystrophy.

Rescue of dystrophic skeletal muscle in mdx and utrophin/dystrophin-deficient (dko) mouse models by reintroduction of dystrophin has validated gene therapy as a potential therapeutic approach for Duchenne muscular dystrophy. However, the size of the dystrophin gene exceeds the capacity of adeno-associated viral (AAV) vectors. Dystrophin provides a mechanical link at the muscle membrane by direct binding of its amino-terminal and cysteine-rich domains to actin and a transmembrane protein complex, respectively. It has not been investigated whether restoration of these two tethering functions by two separate dystrophin molecules is sufficient to prevent dystrophic pathologies. We examine the effect of coexpression of the amino-terminal and cysteine-rich domains from separate dystrophin transgenes, Deltacys and Dp71, on the dystrophic phenotype. Expression of individual dystrophin domains from multiple vectors would effectively expand AAV capacity. Although both Deltacys and Dp71 colocalize at the membrane, there is no improvement of dystrophic pathology. The fiber-type and neuromuscular junction abnormalities of dko mice that are ameliorated by the Deltacys transgene are not further improved or disrupted by Dp71. Separate truncated dystrophins, which together restore all protein interactions and scaffolding for signaling molecules, are not sufficient to ameliorate the dystrophic phenotype and therefore dystrophin domains in trans cannot be used to increase the effective cloning capacity for AAV-mediated gene therapy.

Karyotypic analysis of adult pluripotent stem cells.

Three categories of precursor cells have been identified in postnatal mammals: tissue-committed progenitor cells, germ layer lineage-committed stem cells and lineage-uncommitted pluripotent stem cells. Progenitor cells are the immediate precursors of differentiated tissues. Germ layer lineage stem cells can be induced to form multiple cell types belonging to their respective ectodermal, mesodermal, and endodermal embryological lineages. Pluripotent stem cells will form somatic cell types from all three primary germ layer lineages. Progenitor cells demonstrate a finite life span before replicative senescence and cell death occur. Both germ layer lineage stem cells and pluripotent stem cells are telomerase positive and display extensive capabilities for self-renewal. Stem cells which undergo such extensive replication have the potential for undergoing mutations that may subsequently alter cellular functions. Gross mutations in the genome may be visualized as chromosomal aneuploidy and/or chromosomes that appear aberrant. This study was designed to determine whether any gross genomic mutations occurred within the adult pluripotent stem cells. Karyotypic analysis was performed using pluripotent stem cells purified from adult male rats using established procedures. Giemsa Banding was used in conjunction with light microscopy to visualize metaphase chromosome spreads. To date over 800 metaphase spreads have been analyzed. We found that the metaphase spreads averaged 42 chromosomes and concluded that these pluripotent stem cells isolated from adult rats have a normal karyotype.

VEGF-induced phosphorylation of Bcl-2 influences B lineage leukemic cell response to apoptotic stimuli.

Post-translational modification of Bcl-2 protein has been described in a variety of cell models with effects varying from enhanced to abrogated function. In this study, we demonstrated that Bcl-2 was constitutively phosphorylated in several hematopoietic tumor cell lines and in primary ALL cells. Increased phosphorylation of Bcl-2 protein in the JM1 ALL cell line, achieved by expression of the phosphomimetic Bcl-2 construct S70E, enhanced JM1 cell chemoresistance. In contrast, initiation of JM1 cell apoptosis was coincident with dephosphorylation of Bcl-2 and elevated protein phosphatase 2A activity. S70E expression also diminished tBid-mediated cytochrome c release and blunted chemotherapy-induced activation of caspases-9 and -3 in JM1 cells. To determine whether soluble factors produced by stromal cells in the bone marrow influence phosphorylation of Bcl-2 protein, a panel of recombinant cytokines was evaluated. Of those tested, vascular endothelial growth factor (VEGF) induced phosphorylation of Bcl-2 protein and blunted cytochrome c release during chemotherapy or tBid treatment of ALL cells. In contrast, JM1 cells transfected with S70A, resulting in expression of Bcl-2 protein that cannot be phosphorylated, were not efficiently rescued from apoptosis by VEGF. These observations suggest that optimal protection of leukemic cells by VEGF may require activation of a pathway that includes Bcl-2 phosphorylation.

Depo medroxyprogesterone acetate (DMPA) and combined oral contraceptives and cervical carcinoma in-situ in women aged 50 years and under

Most low-resource settings depend on hormonal contraceptives for their family planning programmes and cervical cancer occurs in higher frequency in these populations. To determine whether hormonal contraception use increases cervical carcinoma in-situ (CIS) risk, a case-control study was conducted in the Kingston and St Andrew Corporate area of Jamaica, using 119 cases from the Jamaica Tumour Registry and 304 population controls matched on year of Papanicolaou (Pap) smear and clinic where Pap smear was obtained. While CIS cases were more likely to have 'ever used' combined oral contraceptives (COC) (OR = 1.4, 95 CI: 0.8, 2.5), depo-medroxyprogesterone acetate (DMPA) use was similar. Compared to women who never used hormonal contraceptives, the risk of CIS was elevated in: women who had used COCs five years or more (OR = 2.1, 95 CI: 1.0, 4.6), women who first used COC for less than 10 years prior to the interview (OR = 1.8, 95 CI: 0.9, 3.7) and women who were 18 to 24 years old when they first used COCs (OR = 1.8, 95 CI: 0.9, 3.4). Similarly, compared to women who never used DMPA, the risk of CIS was elevated in: women using DMPA five years or more (OR = 1.9, 95 CI: 0.7, 4.8), women reporting use within a year prior to interview (OR = 2.8, 95 CI: 0.7, 10.7) and women who initiated use of DMPA when they were 20 and 24 years old (OR = 1.4, 95 CI: 0.7, 3.1). These results suggest that if hormonal contraceptive use confers any risk of CIS, it is confined to long-term users. Increased risk in some groups, however, warrant further study

Etoposide differentially affects bone marrow and dermal derived endothelial cells.

Chemotherapy alteration of the bone marrow microenvironment has the potential to influence hematopoietic recovery following transplantation. To discern the effect of specific drugs on components of the complex marrow microenvironment, in vitro models have significant utility. In the current study we sought to determine whether dermal (HMEC-1) and marrow derived endothelial cells (BMEC-1) respond differently to identical chemotherapy exposure. BMEC-1 cells were consistently more sensitive to etoposide exposure than HMEC-1 cells, measured as reduced viability. BMEC-1 also had reduced focal adhesion kinase (FAK) and VCAM-1 protein expression following chemotherapy, in contrast to dermal derived endothelial cells in which neither protein was influenced dramatically by etoposide. The two endothelial cell lines had markedly different levels of baseline VE-Cadherin protein, which was modestly altered by treatment. These data indicate that marrow derived endothelial cells have disruption of specific proteins following chemotherapy that may influence their ability to facilitate hematopoietic cell entry or egress from the marrow. In addition, these observations suggest that while BMEC-1 and HMEC-1 share a variety of characteristics, they differ significantly in their response to stress and should be incorporated into specific models with this consideration.

Puerperal sepsis and maternal mortality: what role can new technologies play?

OBJECTIVE: To identify new and underutilized technologies to reduce maternal mortality related to puerperal sepsis in developing countries. METHOD: Review of current medical literature. RESULT: The literature indicates that infection-control protocols and evidence-based procedures--including prophylactic antibiotics for cesarean section or preterm rupture of membranes, and updated antibiotic regimens--should be widely adopted. Devices such as hand rubs, needle-disposal systems, and rapid microbiological diagnostic tests can improve compliance and efficiency. Operational research on promising developments like vaginal cleansing with antiseptics, vitamin A supplementation, and prophylactic antibiotics in high-risk women is needed. CONCLUSION: Sepsis management continues to depend on good implementation of established technologies. Program-based approaches are required to improve uptake.