One of the most intriguing, long‐standing questions regarding Venus's atmosphere is the origin and distribution of the unknown UV absorber, responsible for the absorption band detected at the near‐UV ...and blue range of Venus's spectrum. In this work, we use data collected by Mercury Atmospheric and Surface Composition Spectrometer (MASCS) spectrograph on board the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission during its second Venus flyby in June 2007 to address this issue. Spectra range from 0.3 μm to 1.5 μm including some gaseous H2O and CO2 bands, as well as part of the SO2 absorption band and the core of the UV absorption. We used the NEMESIS radiative transfer code and retrieval suite to investigate the vertical distribution of particles in the equatorial atmosphere and to retrieve the imaginary refractive indices of the UV absorber, assumed to be well mixed with Venus's small mode 1 particles. The results show a homogeneous equatorial atmosphere, with cloud tops (height for unity optical depth) at 75 ± 2 km above surface. The UV absorption is found to be centered at 0.34 ± 0.03 μm with a full width at half maximum of 0.14 ± 0.01 μm. Our values are compared with previous candidates for the UV aerosol absorber, among which disulfur oxide (S2O) and dioxide disulfur (S2O2) provide the best agreement with our results.
Plain Language Summary
The atmosphere of Venus is fully cloud covered, and its clouds are very reflective in most visual wavelengths, with the exception of the near ultraviolet, where an absorber of unknown origin strongly absorbs solar radiation. Such a mysterious absorber provides contrast to many atmospheric features whose dynamics can be tracked from images, and it also has a substantial role in the energy budget of the planet. But, as of today, we have no clear idea what it is made of. In this work, we have analyzed spectra taken during the second Venus flyby of MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft on its route to Mercury, in 2007. Using a numerical code, we have reproduced the light reflected by the equatorial atmosphere of the planet and retrieved the distribution of particles in the upper atmosphere of Venus, with a cloud top of some 75 km above the surface. We have also retrieved the absorption spectrum of the puzzling absorber and compared it with some previously proposed candidates. While no perfect match is found, sulfur‐bearing species (S2O and S2O2) provide the best agreement. There is still a long way to undoubtedly identify Venus's UV absorber, but this work provides substantial spectral constraints.
Key Points
We analyze spectra of Venus's equatorial atmosphere taken during the second MESSENGER flyby on 5 June 2007
Cloud tops are located at 75 ± 2 km in the equatorial atmosphere.
Among all candidates proposed so far, S2O and S2O2, with subindices provide the best agreement with the UV absorption retrieved here
•Hybrid cluster analyses revealed three decision-making profiles during the IGT.•Profiles contained the same proportion of participants of each diagnostic category.•Bayesian GLM showed no ...relationship between FPN and behavior during the IGT.
The Iowa Gambling Task (IGT) is one of the most widely used paradigms for assessing decision-making. An impairment in this process may be linked to several psychopathological disorders, such as obsessive–compulsive disorder (OCD), substance abuse disorder (SUD) or attention-deficit/hyperactivity disorder (ADHD), which could make it a good candidate for being consider a transdiagnostic domain. Resting-state functional connectivity (rsFC) has been proposed as a promising biomarker of decision-making. In this study, we aimed to identify idiosyncratic decision-making profiles among healthy people and impulsive-compulsive spectrum patients during the IGT, and to investigate the role of frontoparietal network (FPN) rsFC as a possible biomarker of different decision-making patterns. Using functional near-infrared spectroscopy (fNIRS), rsFC of 114 adults (34 controls; 25 OCD; 41 SUD; 14 ADHD) was obtained. Then, they completed the IGT. Hybrid clustering methods based on individual deck choices yielded three decision-makers subgroups. Cluster 1 (n = 27) showed a long-term advantageous strategy. Cluster 2 (n = 25) presented a maladaptive decision-making strategy. Cluster 3 (n = 62) did not develop a preference for any deck during the task. Interestingly, the proportion of participants in each cluster was not different between diagnostic groups. A Bayesian general linear model showed no credible differences in the IGT performance between diagnostic groups nor credible evidence to support the role of FPN rsFC as a biomarker of decision-making under the IGT context. This study highlights the importance of exploring in depth the behavioral and neurophysiological variables that may drive decision-making in clinical and healthy populations.
Lipid peroxidation and iron accumulation are closely associated with neurodegenerative diseases, such as Alzheimer's, Parkinson's, and Huntington's diseases, or neurodegeneration with brain iron ...accumulation disorders. Mitochondrial dysfunction, lipofuscin accumulation, autophagy disruption, and ferroptosis have been implicated as the critical pathomechanisms of lipid peroxidation and iron accumulation in these disorders. Currently, the connection between lipid peroxidation and iron accumulation and the initial cause or consequence in neurodegeneration processes is unclear. In this review, we have compiled the known mechanisms by which lipid peroxidation triggers iron accumulation and lipofuscin formation, and the effect of iron overload on lipid peroxidation and cellular function. The vicious cycle established between both pathological alterations may lead to the development of neurodegeneration. Therefore, the investigation of these mechanisms is essential for exploring therapeutic strategies to restrict neurodegeneration. In addition, we discuss the interplay between lipid peroxidation and iron accumulation in neurodegeneration, particularly in PLA2G6-associated neurodegeneration, a rare neurodegenerative disease with autosomal recessive inheritance, which belongs to the group of neurodegeneration with brain iron accumulation disorders.
We present the morphology and linear polarization of the 22-GHz water (H2O) masers in the high-velocity outflow of two post-asymptotic giant branch sources, d46 (IRAS 15445−5449) and b292 (IRAS ...18043−2116). The observations were performed using the Australia Telescope Compact Array. Different levels of saturated maser emission have been detected for both sources. We also present the mid-infrared image of d46 overlaid with the distribution of the maser features that we have observed in the redshifted lobe of the bipolar structure. The relative position of the observed masers and a previous radio continuum observation suggest that the continuum is produced along the blueshifted lobe of the jet. It is likely due to synchrotron radiation, implying the presence of a strong magnetic field in the jet. The fractional polarization levels measured for the maser features of d46 indicate that the polarization vectors are tracing the poloidal component of the magnetic field in the emitting region. For the H2O masers of b292, we have measured low levels of fractional linear polarization. The linear polarization in the H2O maser region of this source likely indicates a dominant toroidal or poloidal magnetic field component. Since circular polarization was not detected, it is not possible to determine the magnetic field strength. However, we present a 3σ evaluation of the upper limit intensity of the magnetic field in the maser-emitting regions of both observed sources.
We present P 3D, an analysis pipeline based on the FIT3D fitting tool, developed to explore the properties of the stellar populations and ionized gas of integral field spectroscopy (IFS) data. P 3D ...was created to provide coherent, simple to distribute, and comparable dataproducts, independently of the origin of the data, focused on the data of the most recent IFU surveys (e.g., CALIFA, MaNGA, and SAMI), and the last generation IFS instruments (e.g., MUSE). In this article we describe the different steps involved in the analysis of the data, illustrating them by showing the dataproducts derived for NGC 2916, observed by CALIFA and P-MaNGA. As a practical example of the pipeline we present the complete set of dataproducts derived for the 200 datacubes that comprises the V500 setup of the CALIFA Data Release 2 (DR2), making them freely available through the network. Finally, we explore the hypothesis that the properties of the stellar populations and ionized gas of galaxies at the effective radius are representative of the overall average ones, finding that this is indeed the case.
Our purpose is to adapt a statistical method for the analysis of discrete numerical series to the keywords appearing in scientific articles of a given area. As an example, we apply our methodological ...approach to the study of the keywords in the Library and Information Sciences (LIS) area. Our objective is to detect the new author keywords that appear in a fixed knowledge area in the period of 1 year in order to quantify the probabilities of survival for 10 years as a function of the impact of the journals where they appeared. Many of the new keywords appearing in the LIS field are ephemeral. Actually, more than half are never used again. In general, the terms most commonly used in the LIS area come from other areas. The average survival time of these keywords is approximately 3 years, being slightly higher in the case of words that were published in journals classified in the second quartile of the area. We believe that measuring the appearance and disappearance of terms will allow understanding some relevant aspects of the evolution of a discipline, providing in this way a new bibliometric approach.
ABSTRACT The "main sequence of galaxies"-defined in terms of the total star formation rate versus the total stellar mass M*-is a well-studied tight relation that has been observed at several ...wavelengths and at different redshifts. All earlier studies have derived this relation from integrated properties of galaxies. We recover the same relation from an analysis of spatially resolved properties, with integral field spectroscopic (IFS) observations of 306 galaxies from the CALIFA survey. We consider the SFR surface density in units of log(M yr−1 Kpc−2) and the stellar mass surface density in units of log(M Kpc−2) in individual spaxels that probe spatial scales of 0.5-1.5 Kpc. This local relation exhibits a high degree of correlation with small scatter ( = 0.23 dex), irrespective of the dominant ionization source of the host galaxy or its integrated stellar mass. We highlight (i) the integrated star formation main sequence formed by galaxies whose dominant ionization process is related to star formation, for which we find a slope of 0.81 0.02; (ii) for the spatially resolved relation obtained with the spaxel analysis, we find a slope of 0.72 0.04; and (iii) for the integrated main sequence, we also identified a sequence formed by galaxies that are dominated by an old stellar population, which we have called the retired galaxies sequence.
The epidemiological surveillance of contact dermatitis is one of the objectives of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. Knowing whether the prevalence of ...positive tests to the different allergens changes over time is important for this monitoring process.
To describe the various temporary trends in allergen positivity in the GEIDAC standard series from 2018 through December 31, 2022.
This was a multicenter, observational trial of consecutive patients analyzed via patch tests as part of the study of possible allergic contact dermatitises collected prospectively within the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. The data was analyzed using 2 statistical tests: one homogeneity test (to describe the changes seen over time) and one trend test (to see whether the changes described followed a linear trend).
A total of 11327 patients were included in the study. Overall, the allergens associated with a highest sensitization were nickel sulfate, methylisothiazolinone, cobalt chloride, methylchloroisothiazolinone/methylisothiazolinone, and fragrance mix i. A statistically significant decrease was found in the percentage of methylisothiazolinone positive tests across the study years with an orderly trend.
Although various changes were seen in the sensitizations trends to several allergens of the standard testing, it became obvious that a high sensitization to nickel, methylchloroisothiazolinone/methylisothiazolinone and fragrances mix i remained. Only a significant downward trend was seen for methylisothiazolinone.
El Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea tiene entre sus objetivos la vigilancia epidemiológica de la dermatitis de contacto. Para ello es importante conocer si se producen alteraciones en el tiempo de las prevalencias de las positividades a los distintos alérgenos.
Describir las variaciones en las tendencias temporales en positividades a alérgenos en la serie estándar del GEIDAC en el periodo comprendido entre 2018 y el 31 de diciembre de 2022.
Estudio observacional multicéntrico de pacientes estudiados consecutivamente mediante pruebas epicutáneas dentro del estudio de un posible eczema alérgico de contacto recogidos de forma prospectiva en el seno del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea. Se analizaron los datos mediante 2 pruebas estadísticas: una de homogeneidad (para ver si hay cambios en los diferentes años) y otra de tendencia (para ver si los cambios siguen una tendencia lineal).
Se incluyeron un total de 11.327 pacientes en el periodo de estudio. Los alérgenos en los que de forma global se detectó una sensibilización mayor fueron sulfato de níquel, metilisotiazolinona, cloruro de cobalto, metilcloroisotiazolinona/metilisotiazolinona y mezcla de fragancias i. Se detectó una disminución estadísticamente significativa en el porcentaje de positividades de metilisotiazolinona a lo largo de años de estudio con una tendencia ordenada.
Si bien se pueden apreciar diferentes cambios en las tendencias a sensibilizaciones a varios de los alérgenos de la batería estándar, se observa que persiste una alta sensibilización al níquel, a la metilcloroisotiazolinona/metilisotiazolinona y a la mezcla de fragancias i. Solo se aprecia una tendencia a disminuir de forma significativa en el caso de la metilisotiazolinona.
We use spatially and temporally resolved maps of stellar population properties of 300 galaxies from the CALIFA integral field survey to investigate how the stellar metallicity (Z sub(*)) relates to ...the total stellar mass (M sub(*)) and the local mass surface density ( mu sub(*)) in both spheroidal- and disk-dominated galaxies. The galaxies are shown to follow a clear stellar mass-metallicity relation (MZR) over the whole 10 super(9)-10 super(12) M sub(middot in circle) range. This relation is steeper than the one derived from nebular abundances, which is similar to the flatter stellar MZR derived when we consider only young stars. We also find a strong relation between the local values of mu sub(*) and Z sub(*) (the mu ZR), betraying the influence of local factors in determining Z sub(*). This shows that both local ( mu sub(*)-driven) and global (M sub(*)-driven) processes are important in determining metallicity in galaxies. We find that the overall balance between local and global effects varies with the location within a galaxy. In disks, mu sub(*) regulates Z sub(*), producing a strong mu ZR whose amplitude is modulated by M sub(*). In spheroids it is M sub(*) that dominates the physics of star formation and chemical enrichment, with mu sub(*) playing a minor, secondary role. These findings agree with our previous analysis of the star formation histories of CALIFA galaxies, which showed that mean stellar ages are mainly governed by surface density in galaxy disks and by total mass in spheroids.