High signal-to-noise spectral characterization of the planetary-mass object HD 106906 b

We spectroscopically characterize the atmosphere of HD 106906b, a young low-mass companion near the deuterium burning limit. The wide separation from its host star of 7.1" makes it an ideal candidate for high S/N and high-resolution spectroscopy. We aim to derive new constraints on the spectral type, effective temperature, and luminosity of HD106906b and also to provide a high S/N template spectrum for future characterization of extrasolar planets. We obtained 1.1-2.5 $\mu$m integral field spectroscopy with the VLT/SINFONI instrument with a spectral resolution of R~2000-4000. New estimates of the parameters of HD 106906b are derived by analyzing spectral features, comparing the extracted spectra to spectral catalogs of other low-mass objects, and fitting with theoretical isochrones. We identify several spectral absorption lines that are consistent with a low mass for HD 106906b. We derive a new spectral type of L1.5$\pm$1.0, one subclass earlier than previous estimates. Through comparison with other young low-mass objects, this translates to a luminosity of log($L/L_\odot$)=$-3.65\pm0.08$ and an effective temperature of Teff=$1820\pm240$ K. Our new mass estimates range between $M=11.9^{+1.7}_{-0.8} M_{\rm Jup}$ (hot start) and $M=14.0^{+0.2}_{-0.5} M_{\rm Jup}$ (cold start). These limits take into account a possibly finite formation time, i.e., HD 106906b is allowed to be 0--3 Myr younger than its host star. We exclude accretion onto HD 106906b at rates $\dot{M}>4.8\times10^{-10} M_{\rm Jup}$yr$^{-1}$ based on the fact that we observe no hydrogen (Paschen-$\beta$, Brackett-$\gamma$) emission. This is indicative of little or no circumplanetary gas. With our new observations, HD 106906b is the planetary-mass object with one of the highest S/N spectra yet. We make the spectrum available for future comparison with data from existing and next-generation (e.g., ELT and JWST) spectrographs.Comment: 11 pages, 5 figures. Accepted for publication in Astronomy & Astrophysics. Fully reduced spectra will be made available for download on CD

Role of adventitia in vascular remodeling in hypertension: a trophobiological view

The vascular wall has the capacity to undergo remodeling in response to long-term changes or injuries. This is a process of structural rearrangement that involves cell growth, cell death, cell migration, cell modulation and secretion/degradation of extracellular matrix molecules. Vascular remodeling is an adaptive phenomenon, e.g. Glagov's compensatory enlargement in atherosclerosis, but it may grow into vascular diseases, such as hypertension, atherosclerosis, and coronary restenosis after angioplasty. Nowadays paradigms defining the cell biology of vascular diseases are the following: (i) the hypertensive vessel is characterized by hyperinnervation-associated medial thickening due to smooth muscle cell (SMC) hypertrophy/hyperplasia and increased extracellular matrix content, (ii) the atherosclerotic plaque is characterized by SMC/immune cells/increased extracellular matrix-containing intimal thickening, and (iii) the restenotic coronary artery is characterized by SMC/immune cells-containing neointimal thickening. The spontaneously hypertensive rats (SHR), the stroke-prone SHR (SHRSP), the genetically hypertensive (GH) rats, and other genetically hypertensive strains are widely used as a model of human essential hypertension. In this volume of Biomedical Reviews, Bell updates the knowledge about vascular wall neurotrophobiology in relation to the pathogenesis of hypertension in SHR and GH rats. Also, Kondo et al systematize the perivascular nerve-related SMC structural changes in the development of hypertension in SHR and SHRSP. The data presented in these reviews are evaluated mainly in terms of Levi-Montalcini's neurotrophic theory.Biomedical Reviews 1996; 6: 5-10

555. Development of a Post-Exposure Treatment for Ebola Virus Infections Based on AAV Vectors and Zmapp Antibody Cocktail

The recent Ebola outbreak in West Africa has been the deadliest in the history. To prevent future recurrence of such outbreak, better treatments and effective vaccines against Ebola virus are desirable. Among such promising treatments, the Zmapp cocktail containing neutralizing antibodies (13C6, 2G4 and 4G7) has successfully treated some patients. However, the feasibility of using it on large populations especially in developing countries is questionable. To address this potential issue, we propose to employ recombinant vectors derived from adeno-associated virus (rAAV). There are several advantages of using rAAV: because of 1) their safety profile; 2) only one injection (or a few) would be required; 3) the high stability of lyophilized rAAVs at ambient temperature and; 4) the panel of available serotypes. Because of these interesting features, we are currently developing a treatment based on three rAAVs to deliver the genes for the Zmapp cocktail of antibodies. We have already produced at small scale a rAAV expressing the 2G4 antibody. The DNA sequences for the heavy chain and light chains were codon-optimized for better expression in humans and were designed to be expressed from the same gene. A strong promoter (CAG) resistant to silencing in vivo was chosen to drive gene expression of the antibody. The rAAV were produced by transfection using our patented cGMP compatible HEK293 cell line. The production was performed in suspension culture in the absence of serum. Secretion of 2G4 antibody by rAAV transduced cells (HEK293 and CHO cells) was confirmed. The results demonstrated that rAAV-CAG-2G4 was functional and allowed for the correct assembly of the heavy and light chains of 2G4. Purification of 200 mL of rAAV-CAG-2G4 production was performed by ultracentrifugation on an iodixanol density-step gradient. Two other rAAVs coding 13C6 and 4G7 antibodies are in the processed of being constructed and produced in a similar manner. We are also in the process of comparing the efficacy of two serotypes of AAV (9 and DJ) in mice by intranasal delivery. Using the best serotype, the rAAVs will be produced and purified from a starting suspension culture of 20 L. Their efficacy for treating Ebola infections will then be evaluated in a mouse model infected by the virus

Phase curves of WASP-33b and HD 149026b and a New Correlation Between Phase Curve Offset and Irradiation Temperature

We present new 3.6 and 4.5 $\mu m$ Spitzer phase curves for the highly irradiated hot Jupiter WASP-33b and the unusually dense Saturn-mass planet HD 149026b. As part of this analysis, we develop a new variant of pixel level decorrelation that is effective at removing intrapixel sensitivity variations for long observations (>10 hours) where the position of the star can vary by a significant fraction of a pixel. Using this algorithm, we measure eclipse depths, phase amplitudes, and phase offsets for both planets at 3.6 $\mu m$ and 4.5 $\mu m$. We use a simple toy model to show that WASP-33b's phase offset, albedo, and heat recirculation efficiency are largely similar to those of other hot Jupiters despite its very high irradiation. On the other hand, our fits for HD 149026b prefer a very high albedo and an unusually high recirculation efficiency. We also compare our results to predictions from general circulation models, and find that while neither are a good match to the data, the discrepancies for HD 149026b are especially large. We speculate that this may be related to its high bulk metallicity, which could lead to enhanced atmospheric opacities and the formation of reflective cloud layers in localized regions of the atmosphere. We then place these two planets in a broader context by exploring relationships between the temperatures, albedos, heat transport efficiencies, and phase offsets of all planets with published thermal phase curves. We find a striking relationship between phase offset and irradiation temperature--the former drops with increasing temperature until around 3400 K, and rises thereafter. Although some aspects of this trend are mirrored in the circulation models, there are notable differences that provide important clues for future modeling efforts

Leydig cell-immune cell interaction: an example of neuroendocrine-immune communication in testis

In her paper "Tilings will never be the same again" Dr Kathleen L. Wishner quoted Alvin Toffler's book Future Shock written in 1970. Toffler defined "future shock" as a time phenomenon, a product of the greatly accelerated change in society. The scientific research itself is a demonstration of this accelerated change. In particular, data systematized by Davidoff et al in this volume of Biomedical Reviews indicate the change in the understanding of the nature and origin of Leydig cells of the human testis.Biomedical Reviews 1996; 6: 1-4

Statistical Modelling of Drying Characteristics of Unripe Plantain (Musa Paradisiaca) Slices

This work is designed to carry out the statistical modelling of the drying characteristics of unripe plantain (Musa paradisiaca) slices and to study the effect of drying temperature and slice thickness on drying characteristics. The test samples were dried in a laboratory scale oven dryer at varying temperatures of 700C, 800C and 900C, and different slice thicknesses of 2mm, 3mm and 4mm.The result obtained indicated that drying temperature and slice thickness had significant effect on drying rate and hence moisture profile. The moisture ratio – drying time data obtained were fitted to ten thin layer drying models. The fit quality obtained with each model was evaluated using statistical tests namely; coefficient of determination (R2), root mean square error (RMSE), reduced chi-square (X2), and standard error of estimate (SEE). Although most of the models fitted quite well to the experimental data, Page and Modified Page models showed the highest average R2 and the lowest average RMSE, X2 and SEE values. Page and modified Page models were selected and found suitable to represent the drying characteristics of unripe plantain slices and predict drying times