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A new generative technique is presented in this paper that uses Deep Learning to reconstruct stellar spectra based on a set of stellar parameters. Two different Neural Networks were trained allowing the generation of new spectra. First, an autoencoder is trained on a set of BAFGK synthetic data calculated using ATLAS9 model atmospheres and SYNSPEC radiative transfer code. These spectra are calculated in the wavelength range of Gaia RVS between 8400 and 8800 Å. Second, we trained a Fully Dense Neural Network to relate the stellar parameters to the Latent Space of the autoencoder. Finally, we linked the Fully Dense Neural Network to the decoder part of the autoencoder and we built a model that uses as input any combination of $T_{\mathrm{eff}}$, $logg$, $v_{e}sini$, $[M/H]$, and ${\xi }_t$ and output a normalized spectrum. The generated spectra are shown to represent all the line profiles and flux values as the ones calculated using the classical radiative transfer code. The accuracy of our technique is tested using a stellar parameter determination procedure and the results show that the generated spectra have the same characteristics as the synthetic ones. Full article

Introduction: Right ventricular (RV) function in the setting of pulmonary hypertension based on different etiologies has not been well studied. In this study, we evaluated the RV function in patients with idiopathic pulmonary hypertension (IPH) versus secon-dary pulmonary hypertension (SPH) due to congestive heart failure. Material and method: Forty-five patients with pulmonary hypertension and New York Heart Association (NYHA) functional class II or III were enrolled. Of these, 22 were diagnosed with IPH and 23 with SPH. Echocardiographic data, including Doppler and Doppler based strain, were assessed according to the American Society of Echocardiography (ASE) Guideliness for detailed evaluation of RV function in these two groups. Results: Mean PAP was 60 ± 14.5 mm Hg in patients with IPH versus 43 ± 11.5 mm Hg in patients with SPH (p = 0.001). Considering conventional indexes of RV function, only Sm and dp/dt were significantly better in the first group compared with the second group (p-value for Sm = 0.042 and for dp/dt = 0.039). RV end diastolic dimension was significantly higher in the IPH group (p = 0.013). Using deformation indexes of RV function, the basal and mid portion of RV free wall strain and basal RV strain rates were significantly worse in the chronic systolic heart failure (PH-HF) group in comparison to the IPH group (p < 0.001 in basal RV strain, p = 0.034 in mid RV strain and p = 0.046 in basal RV strain rate respectively). Conclusion: IPH has less impact on RV function in comparison to PH-HF. Considering both entities are in the category of RV pressure overload, we conclude that the etiology of pulmonary hypertension also plays an important role in RV function in addition to pressure overload. Full article

Cyclostellettamines A – F (1 – 6) isolated from the sponge Pachychalina sp. and cyclostellettamines G - I, K and L (7 – 11) obtained by synthesis were evaluated in bioassays of antimicrobial activity against susceptible and antibiotic-resistant Staphylococcus aureus, Pseudomonas aeruginosa and antibiotic-susceptible Escherichia coli and Candida albicans, as well as in antimycobacterial activity against Mycobacterium tuberculosis H37Rv bioassays. The results obtained indicated that cyclostellettamines display different antimicrobial activity depending on the alkyl-chain size, suggesting that, if a mechanism-of action is implied, it is dependent on the distance between the two pyridinium moieties of cyclostellettamines. Full article