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There exist very few mid-infrared (IR) observations of supernovae (SNe) in general. Therefore, SN 1987A, the closest visible SN in 400 yr, gives us the opportunity to explore the mid-IR properties of SNe, the dust in their ejecta, and the surrounding medium and to witness the birth of an SN remnant (SNR). The James Webb Space Telescope, with its high spatial resolution and extreme sensitivity, gives a new view on these issues. We report on the first imaging observations obtained with the Mid-InfraRed Instrument (MIRI). We build temperature maps and discuss the morphology of the nascent SNR. Our results show that the temperatures in the equatorial ring (ER) are quite nonuniform. This could be due to dust destruction in some parts of the ring, as had been assumed in some previous works. We show that the IR emission extends beyond the ER, illustrating the fact that the shock wave has now passed through this ring to affect the circumstellar medium on a larger scale. Finally, while submillimeter Atacama Large Millimeter Array observations have hinted at the location of the compact remnant of SN 1987A, we note that our MIRI data have found no such evidence.

By using an ultradeep JWST/MIRI image at 5.6 μ m in the Hubble eXtreme Deep Field, we constrain the role of strong H α emitters (HAEs) during “cosmic reionization” at z ≃ 7–8. Our sample of HAEs is comprised of young (

We investigate the properties of strong (H β + [O iii ]) emitters before and after the end of the “Epoch of Reionization” from z = 8 to z = 5.5. We make use of ultradeep JWST / NIRCam imaging in the parallel field (P2) of the MIRI Deep Imaging Survey (MIDIS) in the Hubble eXtreme Deep Field (H-XDF), in order to select prominent (H β + [O iii ]) emitters (with rest-frame equivalent width (EW _0 ) ≳ 100 Å) at z = 5.5–7, based on their flux density enhancement in the F356W band with respect to the spectral energy distribution continuum. We complement our selection with other (H β + [O iii ]) emitters from the literature at similar and higher ( z = 7−8) redshifts. We find (nonindependent) anticorrelations between EW _0 (H β + [O iii ]) and both galaxy stellar mass and age, in agreement with previous studies, and a positive correlation with specific star formation rate (sSFR). On the SFR– M ^⋆ plane, the (H β + [O iii ]) emitters populate both the star formation main sequence and the starburst region, which become indistinguishable at low stellar masses ( ${\mathrm{log}}_{10}({M}^{\star })\lt 7.5$ ). We find tentative evidence for a nonmonotonic relation between EW _0 (H β + [O iii ]) and SFR, such that both parameters correlate with each other at SFR ≳ 1 M _⊙ yr ^−1 , while the correlation flattens out at lower SFRs. This suggests that low metallicities producing high EW _0 (H β + [O iii ]) could be important at low SFR values. Interestingly, the properties of the strong emitters and other galaxies (33% and 67% of our z = 5.5–7 sample, respectively) are similar, including, in many cases, high sSFR. Therefore, it is crucial to consider both emitters and nonemitters to obtain a complete picture of the cosmic star formation activity around the Epoch of Reionization.

The protoclusters in the epoch of reionization, traced by galaxy overdensity regions, are ideal laboratories for studying the process of stellar assembly and cosmic reionization. We present the spectroscopic confirmation of the core of the most distant protocluster at z = 7.88, A2744-z7p9OD, with the James Webb Space Telescope NIRSpec integral field unit spectroscopy. The core region includes as many as four galaxies detected in [O iii ] 4960 and 5008 Å in a small area of ∼3″ × 3″, corresponding to ∼11 × 11 kpc, after the lensing magnification correction. Three member galaxies are also tentatively detected in dust continuum in Atacama Large Millimeter/submillimeter Array Band 6, which is consistent with their red ultraviolet continuum slopes, β ∼ −1.3. The member galaxies have stellar masses in the range of log( M _* / M _⊙ ) ∼7.6–9.2 and star formation rates of ∼3–50 M _⊙ yr ^−1 , showing a diversity in their properties. FirstLight cosmological simulations reproduce the physical properties of the member galaxies including the stellar mass, [O iii ] luminosity, and dust-to-stellar mass ratio, and predict that the member galaxies are on the verge of merging in a few to several tens of Myr to become a large galaxy with M _* ∼ 6 × 10 ^9 M _⊙ . The presence of a multiple merger and evolved galaxies in the core region of A2744-z7p9OD indicates that environmental effects are already at work 650 Myr after the Big Bang.

We make use of JWST medium-band and broadband NIRCam imaging, along with ultradeep MIRI 5.6 μ m imaging, in the Hubble eXtreme Deep Field to identify prominent line emitters at z ≃ 7–8. Out of a total of 58 galaxies at z ≃ 7–8, we find 18 robust candidates (≃31%) for (H β + [O iii ]) emitters, based on their enhanced fluxes in the F430M and F444W filters, with EW _0 (H β +[O iii ]) ≃87–2100 Å. Among these emitters, 16 lie in the MIRI coverage area and 12 exhibit a clear flux excess at 5.6 μ m, indicating the simultaneous presence of a prominent H α emission line with EW _0 (H α ) ≃200–3000 Å. This is the first time that H α emission can be detected in individual galaxies at z > 7. The H α line, when present, allows us to separate the contributions of H β and [O iii ] to the (H β +[O iii ]) complex and derive H α -based star formation rates (SFRs). We find that in most cases [O iii ]/H β > 1. Instead, two galaxies have [O iii ]/H β < 1, indicating that the NIRCam flux excess is mainly driven by H β . Most prominent line emitters are very young starbursts or galaxies on their way to/from the starburst cloud. They make for a cosmic SFR density ${\mathrm{log}}_{10}({\rho }_{{\mathrm{SFR}}_{{\rm{H}}\alpha }}/({M}_{\odot }\,{\mathrm{yr}}^{-1}\,{\mathrm{Mpc}}^{-3}))\simeq -2.35$ , which is about a quarter of the total value ( ${\mathrm{log}}_{10}({\rho }_{{\mathrm{SFR}}_{\mathrm{tot}}}/({M}_{\odot }\,{\mathrm{yr}}^{-1}\,{\mathrm{Mpc}}^{-3}))\simeq -1.76$ ) at z ≃ 7–8. Therefore, the strong H α emitters likely had a significant role in reionization.

Supernova (SN) 1987A is the nearest supernova in ∼400 yr. Using the JWST MIRI Medium Resolution Spectrograph, we spatially resolved the ejecta, equatorial ring (ER), and outer rings in the mid-infrared 12,927 days (35.4 yr) after the explosion. The spectra are rich in line and dust continuum emission, both in the ejecta and the ring. The broad emission lines (280–380 km s ^−1 FWHM) that are seen from all singly-ionized species originate from the expanding ER, with properties consistent with dense post-shock cooling gas. Narrower emission lines (100–170 km s ^−1 FWHM) are seen from species originating from a more extended lower-density component whose high ionization may have been produced by shocks progressing through the ER or by the UV radiation pulse associated with the original supernova event. The asymmetric east–west dust emission in the ER has continued to fade, with constant temperature, signifying a reduction in dust mass. Small grains in the ER are preferentially destroyed, with larger grains from the progenitor surviving the transition from SN into SNR. The ER dust is fit with a single set of optical constants, eliminating the need for a secondary featureless hot dust component. We find several broad ejecta emission lines from [Ne ii ], [Ar ii ], [Fe ii ], and [Ni ii ]. With the exception of [Fe ii ] 25.99 μ m, these all originate from the ejecta close to the ring and are likely to be excited by X-rays from the interaction. The [Fe ii ] 5.34 to 25.99 μ m line ratio indicates a temperature of only a few hundred K in the inner core, which is consistent with being powered by ^44 Ti decay.

Se realizó un experimento de campo, con el objetivo de determinar el efecto de las cepas de rizobios en las variables agronómicas de sorgo, bajo las condiciones ambientales de Sancti Spíritus, Cuba. Se utilizaron 12 cepas de Bradyrhizobium sp. procedentes de Sancti Spíritus, así como tres cepas de referencia pertenecientes a diferentes géneros y especies de rizobios. El diseño experimental fue de bloques al azar, con 17 tratamientos y cuatro réplicas. Se realizó análisis de varianza y las diferencias entre medias se hallaron por LSD de Fisher (pA field trial was conducted, with the objective of determining the effect of rhizobium strains on the agronomic variables of sorghum, under the environmental conditions of Sancti Spiritus, Cuba. Twelve Bradyrhizobium sp. strains from Sancti Spiritus were used, as well as three reference strains belonging to different rhizobium genera and species. The experimental design was randomized blocks, with 17 treatments and four replications. Variance analysis was made and the differences among means were found by Fisher's LSD (p

Creutzfeldt-Jakob disease (ECJ) is a sub-acute human encephalopathy and progressive associated with a degeneration central nervous system spongiform (SNC). The ECJ belongs to the encephalopathies group transmissible spongiform with an aberrant protein metabolism prions (PrP). Its pathophysiological mechanism exact is still not known clearly but It is thought that this neurodegeneration is related to protein accumulation altered prionics (5, 13, 14, 24, 37). The protein of prions originally identified in rodents infected with Scrapie, it is encoded for a single copy chromosomal gene, this gene is highly conserved and has been identified in more than 13 species of mammals It is usually composed by two exons not translated into 5 separate for a 2 Kb intron. The prevailing uncertainty about PrP and its conformational malleability I dictate the search for linked genes and regulatory elements that could play an active role, but to date it has not been possible to identify any gene related (molecular carbines, etc.), but if some characteristics have been observed not expected within wild genes of PrP.

Cell transplantation therapy for Parkinson's disease (PD) has received much attention as a potential treatment protocol for this neurodegenerative condition. Although there have been promising successes with this approach, it remains problematic, especially regarding the inability to provide immediate trophic support to the newly grafted cells and the inability to prevent acute and/or long-term graft rejection by the host. To address these issues of cell graftability, we have created a novel tissue construct from isolated rat Sertoli cells (SC) and the NTerra-2 immortalized human neuron precursor cell line (NT2) utilizing NASA-developed simulated microgravity technology. The two cell types were cocultured at a 1:4 (SC/NT2) ratio in the High Aspect Rotating Vessel (HARV) biochamber for 3 days, after which a disc-shaped aggregate (1–4 mm diameter) was formed. Sertoli neuron aggregated cells (SNAC) were collected by gravity sedimentation and processed either for light and electron microscopy or for fluorescent immunocytochemistry. Intra-SNAC clusters of SC and NT2 cells were identified by anti-human mitochondrial protein (huMT—specific for NT2 cells) and cholera toxin subunit B (CTb—specific for SC). There was little evidence of cell death throughout the aggregate and the absence of central necrosis, as might be expected in such a large aggregate in vitro. Ultrastructurally, SC did not express junctional modifications with NT2 cells nor with adjacent SC as is typical of SC in vivo and, in some protocols, in vitro. NT2 cells, however, showed distinct intercellular junction-like densities with adjacent NT2 cells, often defining canaliculi-like channels between the microvillus borders of the cells. The results show that the use of simulated microgravity coculture provides a culture environment suitable for the formation of a unique and viable Sertoli-NT2 (i.e., SNAC) tissue construct displaying intra-aggregate cellular organization. The structural integration of SC with NT2 cells provides a novel transplantable tissue source, which can be tested to determine if SC will suppress rejection of the grafted NT2 cells and provide for their short- and long-term trophic support in situ in the treatment of experimental PD.