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Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period ( P _orb ) of 12.76 days. The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous P _orb from TESS data. We confirmed the transit signal and P _orb using ground-based photometry with MuSCAT2 and MuSCAT3, and validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host star is inactive, with an X-ray-to-bolometric luminosity ratio of $\mathrm{log}{L}_{{\rm{X}}}/{L}_{\mathrm{bol}}\approx -5.7$ . Joint analysis of the light curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 ± 0.05 R _⊕ , a 3 σ mass upper limit of 3.9 M _⊕ , and an equilibrium temperature of 315 ± 6 K assuming zero albedo. The transmission spectroscopy metric (TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST.

Anti-VEGF drugs like ranibizumab can be used to treat retinopathy of prematurity (ROP) by halting the formation of abnormal blood vessels, or lasers can be used to burn the edges of the retina where these vessels are present. The objective is to compare the efficacy for ROP between ranibizumab and laser therapy.Material and methodsElectronic searches will be carried out in medical databases with key words and controlled vocabulary terms. Randomized controlled trials (RCT) will be assessed. The primary outcome will be the full ROP regression. Two reviewers will extract the data using predefined forms and, to assess the quality of the study, we will use RoB 2.0, the tool for randomized controlled trials developed by the Cochrane Collaboration. We used a combination of the inverse-variance approach and random-effects models for the meta-analysis.ResultsThe eyes of 182 preterm infants who had ranibizumab treatment were assessed in a total of 364 eyes, and 135 infants received laser therapy. The follow-up period was between 6 and 24 months. Ranibizumab was not associated with greater regression of ROP compared to laser therapy in preterm infants (RR: 1.09, CI 95%: 0.95–1.24; p: 0.22). Also, ranibizumab was not associated with recurrence of ROP compared to laser therapy in preterm infants (RR: 3.77, CI 95%: 0.55–25.81; p: 0.22).ConclusionsThe efficacy of ranibizumab compared to laser is very uncertain in terms of ROP regression and decreased ROP recurrence in preterm infants.Systematic Review Registrationidentifier PROSPERO (CRD42022324150).

TOI-6255 b (GJ 4256) is an Earth-sized planet (1.079 ± 0.065 R _⊕ ) with an orbital period of only 5.7 hr. With the newly commissioned Keck Planet Finder and CARMENES spectrographs, we determine the planet’s mass to be 1.44 ± 0.14 M _⊕ . The planet is just outside the Roche limit, with P _orb / P _Roche = 1.13 ± 0.10. The strong tidal force likely deforms the planet into a triaxial ellipsoid with a long axis that is ∼10% longer than the short axis. Assuming a reduced stellar tidal quality factor ${Q}_{\star }^{{\prime} }\approx {10}^{7}$ , we predict that tidal orbital decay will cause TOI-6255 to reach the Roche limit in roughly 400 Myr. Such tidal disruptions may produce the possible signatures of planet engulfment that have been seen on stars with anomalously high refractory elemental abundances compared to their conatal binary companions. TOI-6255 b is also a favorable target for searching for star–planet magnetic interactions, which might cause interior melting and hasten orbital decay. TOI-6255 b is a top target (with an Emission Spectroscopy Metric of about 24) for phase-curve observations with the James Webb Space Telescope.

Ahead of upcoming space missions intending to conduct observations of low-mass stars in the ultraviolet (UV) spectral region it becomes imperative to simultaneously conduct atmospheric modeling from the UV to the visible (VIS) and near-infrared (NIR). Investigations on extended spectral regions will help to improve the overall understanding of the diversity of spectral lines arising from very different atmospheric temperature regions. Here we investigate atmosphere models with a chromosphere and transition region for the M2.5V star GJ 436, which hosts a close-in Hot Neptune. The atmosphere models are guided by observed spectral features from the UV to the VIS/NIR originating in the chromosphere and transition region of GJ 436. High-resolution observations from the Hubble Space Telescope and Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs (CARMENES) are used to obtain an appropriate model spectrum for the investigated M dwarf. We use a large set of atomic species considered in nonlocal thermodynamic equilibrium conditions within our PHOENIX model computations to approximate the physics within the low-density atmospheric regions. In order to obtain an overall match for the nonsimultaneous observations, it is necessary to apply a linear combination of two model spectra, where one of them better reproduces the UV lines while the other better represents the lines from the VIS/NIR range. This is needed to adequately handle different activity states across the observations.

Rigorous black-box simulations are useful to describe complex systems. However, it cannot be directly integrated into mathematical programming models in some algebraic modeling environments because of the lack of symbolic formulation. In the present paper, a framework is proposed to embed the Aspen HYSYS process simulator in GAMS using kriging surrogate models to replace the simulator-dependent, black-box objective, and constraints functions. The approach is applied to the energy-efficient C3MR natural gas liquefaction process simulation optimization using multi-start nonlinear programming and the local solver CONOPT in GAMS. Results were compared with two other meta-heuristic approaches, Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), and with the literature. In a small simulation evaluation budget of 20 times the number of decision variables, the proposed optimization approach resulted in 0.2538 kW of compression work per kg of natural gas and surpassed those of the PSO and GA and the previous literature from 2.45 to 15.3 %.

Only a low percentage of the radiation from our Sun is captured by photosynthesis, but this conversion of solar to chemical energy sustains all life on Earth. Photosynthesis could be present in any exoplanetary system fulfilling the main three ingredients for this metabolic route: light, water, and carbon dioxide. To deepen into this idea, the ExoPhot project aims to study the relation between photosynthetic systems and exoplanet conditions around different types of stars by focusing on two aspects: (i) Assessing the photosynthetic fitness of a variety of photopigments (either found on Earth or theoretical) as a function of stellar spectral type, star-exoplanet separation, and planet atmosphere basic parameters, and (ii) delineating a range of stellar, exoplanet, and atmospheric parameters for which photosynthetic activity might be feasible. In order to address these goals, we make use of a new metric, the absorption rate γ, for the evaluation of the exoplanet photosynthetic activity that, based on state-of-the-art planet atmosphere and stellar photosphere spectroscopic models, quantifies the overlap between those models with the absorption spectra of photosynthetic pigments, both terrestrial and theoretical. We provide with a set of results for a combination of photosystems and exoplanetary environments revealing the importance of our metric when compared to previous photosynthesis indicators.

Background: In neonates with meconium aspiration syndrome (MAS), continuous positive airway pressure (CPAP) may be more beneficial compared to endotracheal intubation (ETI). We evaluated the efficacy of CPAP in neonates with MAS. Methods: Four engines were used to search randomized clinical trials (RCTs). We used relative risk (RR) and mean difference (MD) with 95% confidence intervals (95%CI) to assess the effect on dichotomous and continuous outcomes, respectively. In addition, we used the Paule–Mandel (PM) random effects model due to the anticipated lack of events. Results: Three RCTs were included (n = 432). No significant difference was found in mortality (RR = 0.82; 95%CI = 0.54–1.25; I2 = 71%; p = 0.36), need for ventilation (RR = 0.49; 95%CI = 0.15–1.56; I2 = 71%; p = 0.57), and incidence of pneumothorax (RR = 1.24; 95%CI = 0.30–5.12; I2 = 0%; p = 0.77) in the CPAP group compared to the ETI group. Regarding secondary outcomes, compared to the ETI group, no significant differences were found in APGAR at one minute (MD = −1.01; 95%CI −2.97 to 0.94; I2 = 98%; p = 0.31), APGAR at 5 min (MD = −1.00; 95%CI = −2.96 to 0.95; I2 = 99%; p = 0.32), days of hospitalization (MD = −0.52; 95%CI = −1.46 to 0.42; I2 = 94%; p = 0.28), and cord pH (MD = 0.003; 95%CI = −0.01 to 0.02; I2 = 0%; p = 0.79). Conclusions: In patients with MAS, there is no significant effect of CPAP use compared to ETI on primary, specifically on mortality, need for ventilation, the incidence of pneumothorax, and secondary outcomes.

A simple index is desirable to assess the effects on both flat-plate and concentrating photovoltaics of natural changes in the solar spectrum. Some studies have suggested that the relationship between the Average Photon Energy (APE) and the shape of individual global tilted irradiance, global horizontal irradiance, or direct normal irradiance (DNI) spectra is bijective and can therefore be used as a single number to unequivocally replace a complete spectral distribution. This paper reevaluates these studies with a modified methodology to assess whether a one-to-one relationship really exists between APE and spectral DNI. A 12-month dataset collected in Jaén (Spain) using a sun-tracking spectroradiometer provides the necessary spectral DNI data between 350 and 1050 nm. After quality control and filtering, 78,772 valid spectra were analyzed. The methodology is based on a statistical analysis of the spectral distributions binned in 0.02-eV APE intervals, from 1.74 to 1.90 eV. For each interval, both the standard deviation and coefficient of variation (CV) are determined across all 50-nm bands into which the 350–1050-nm waveband is divided. CV stays below 3.5% within the 450–900-nm interval but rises up to 13% outside of it. It is concluded that APE may be approximately assumed to uniquely characterize the DNI spectrum distribution for Jaén (and presumably for locations with similar climates) only over the limited 450–900-nm waveband.

El presente artículo analiza los fundamentos jurídicos y la operación del “Programa Seguro Médico Siglo xxi”, con el objeto de elaborar una propuesta de política pública que permita fortalecer su integración en el sistema jurídico mexicano. Actualmente su funcionamiento está sujeto a disposiciones regulatorias de carácter anual, como son el Presupuesto de Egresos de la Federación y las Reglas de Operación de los programas que se derivan del mismo. Lo anterior rivaliza con la trascendencia que este Programa supone para dotar de efectividad al derecho constitucional a la protección de la salud y, de manera específica, a los niños en sus primeras etapas de vida. En ese sentido, en este trabajo se establecen las líneas generales que permitan consolidar el funcionamiento del “Seguro Médico Siglo xxi” dentro del Sistema de Protección Social en Salud (también llamado Seguro Popular), a través de su incorporación en la Ley General de Salud.

“Free-floating, non-deuterium-burning, substellar objects” are isolated bodies of a few Jupiter masses found in very young open clusters and associations, nearby young moving groups, and in the immediate vicinity of the Sun. They are neither brown dwarfs nor planets. In this paper, their nomenclature, history of discovery, sites of detection, formation mechanisms, and future directions of research are reviewed. Most free-floating, non-deuterium-burning, substellar objects share the same formation mechanism as low-mass stars and brown dwarfs, but there are still a few caveats, such as the value of the opacity mass limit, the minimum mass at which an isolated body can form via turbulent fragmentation from a cloud. The least massive free-floating substellar objects found to date have masses of about 0.004 Msol, but current and future surveys should aim at breaking this record. For that, we may need LSST, Euclid and WFIRST.

Resumen: En este artículo se hace una revisión de las técnicas de optimización más importantes: programación lineal y no lineal con y sin variables discretas, así como de los algoritmos disponibles hasta la fecha para resolver dichos problemas. Además de los problemas clásicos se hace una extensión para incluir problemas planteados mediante disyunciones y relaciones lógicas, optimización global determinista y estocástica, optimización en problemas sin estructura definida y una visión global de los sistemas de modelado algebraico. Palabras clave: Optimización, LP, NLP, MINLP, MILP, Programación disyuntiva, Optimización global