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We developed SaludConectaMX as a comprehensive system to track and understand the determinants of complications throughout chemotherapy treatment for children with cancer in Mexico. SaludConectaMX is unique in that it integrates patient clinical indicators with social determinants and caregiver mental health, forming a social-clinical perspective of the patient's evolving health trajectory. The system is composed of a web application (for hospital staff) and a mobile application (for family caregivers), providing the opportunity for cooperative patient monitoring in both hospital and home settings. This paper presents the system's preliminary design and usability evaluation results from a 1.5-year pilot study. Our findings indicate that while the hospital web app demonstrates high completion rates and user satisfaction, the family mobile app requires additional improvements for optimal accessibility; statistical and qualitative data analysis illuminate pathways for system improvement. Based on this evidence, we formalize suggestions for health system development in LMICs, which HCI researchers may leverage in future work.

For a graph $G$, let Conf$(G,n)$ denote the classical configuration space of $n$ labelled points in $G$. Abrams introduced a cubical complex, denoted here by DConf$(G,n)$, sitting inside Conf$(G,n)$ as a strong deformation retract provided $G$ is suitably subdivided. Using discrete Morse Theory techniques, we extend Abrams' result to the realm of configurations having no $k$-fold collisions., Comment: 23 pages, 4 figures

Radio continuum emission from galaxies at gigahertz frequencies can be used as an extinction-free tracer of star formation. However, at frequencies of a few hundred megahertz, there is evidence for low-frequency spectral flattening. We wish to better understand the origin of this low-frequency flattening and, to this end, perform a spatially resolved study of the nearby spiral galaxy M 51. We explore the different effects that can cause flattening of the spectrum towards lower frequencies, such as free-free absorption and cosmic-ray ionisation losses. We used radio continuum intensity maps between 54 and 8350 MHz at eight different frequencies, with observations at 240 MHz from the Giant Metrewave Radio Telescope presented for the first time. We corrected for contribution from thermal free-free emission using an H$\alpha$ map that has been extinction-corrected with 24 $\mu$m data. We fitted free-free absorption models to the radio spectra to determine the emission measure (EM) as well as polynomial functions to measure the non-thermal spectral curvature. The non-thermal low-frequency radio continuum spectrum between 54 and 144 MHz is very flat and even partially inverted, particularly in the spiral arms; contrary, the spectrum at higher frequencies shows the typical non-thermal radio continuum spectrum. However, we do not find any correlation between the EMs calculated from radio and from H$\alpha$ observations; instead, the non-thermal spectral curvature weakly correlates with the HI gas mass surface density. This suggests that cosmic-ray ionisation losses play an important role in the low-frequency spectral flattening. The observed spectral flattening towards low frequencies in M 51 is caused by a combination of ionisation losses and free-free absorption. The reasons for this flattening need to be understood in order to use sub-GHz frequencies as a star-formation tracer.

{We herein report on the calculation of thermoluminescence (TL) kinetic parameters determined from the TL emission of synthetic GdAlO3 (GAO) phosphors prepared by the co-precipitation method. The sample, characterized by means of X-ray diffraction with an orthorhombic phase structure (space group Pnma (62), shows complex glow curves consisting of at least four groups of components peaked at 100, 140, 240, and 290 {\deg}C where the two lower overlapped temperature peaks are difficult to identify using the $T_M-T_{stop}$. The coexistence of a continuum in the trap distribution (linked to the lower temperature peaks) and a discrete trap system (associated with the components at temperatures higher than 200 {\deg}C) can be distinguished. The estimation of the TL kinetic parameters is performed using GlowFit, TLAnal, the spreadsheet Origin, Computing Glow Curve Deconvolution (CGCD), and various heating rate (VHR) methods. However, only CGCD appears as the suitable technique for such purpose since it provides information on the TL physical process supported by mathematical models based on a linear combination of functions related to the First Order Kinetic approach., Comment: 27 pages, 6 figures and 1 table

Star formation estimates based on the counting of YSOs is commonly applied to nearby star-forming regions in the Galaxy. With this method, the SFRs are measured using the counts of YSOs in a particular protostellar Class, a typical protostellar mass, and the lifetime associated with this Class. However, the assumptions underlying the validity of the method such as that of a constant star formation history (SFH) and whether the method is valid for all protostellar Classes has never been fully tested. In this work, we use Monte Carlo models to test the validity of the method. We build synthetic clusters in which stars form at times that are randomly drawn from a specified SFH. The latter is either constant or time-dependent with a burst like behavior. The masses of the protostars are randomly drawn from an IMF which can be either similar to that of the Milky Way field or be variable . For each star in every cluster, the lifetimes associated with the different protostellar classes are also randomly drawn from Gaussian distribution functions centered around their most likely value as suggested by the observations. We find that only the SFR derived using the Class 0 population can reproduce the true SFR at all epochs, and this is true irrespective of the shape of the SFH. For a constant SFH, the SFR derived using the more evolved populations of protostars (Classes I, F, II, and III) reproduce the real SFR only at later epochs which correspond to epochs at which their numbers have reached a steady state. For a time-dependent burst-like SFH, all SFR estimates based on the number counts of the evolved populations fail to reproduce the true SFR. We also show how the offsets between Class I and Class II based SFRs and the true SFR plotted as a function of the number ratios of Class I and Class II versus Class III YSOs can be used in order to constrain the SFH of observed molecular clouds., Comment: Submitted. Comments are welcome

We investigate several panchromatic scaling relations (SRs) for the dwarf irregular galaxy NGC 1569 using IFU data from the Metal-THINGS Survey. Among the spatially resolved properties analyzed, we explore SRs between the stellar mass, SFR, molecular gas, total gas, baryonic mass, gas metallicity, gas fraction, SFE and effective oxygen yields. Such multiwavelength SRs are analyzed at a spatial resolution of 180 pc, by combining our IFU observations with data from the surveys THINGS, CARMA, and archival data from DustPedia. Although we recover several known relations, our slopes are different to previously reported ones. Our star formation main sequence, Kennicutt-Schmidt (KS) and molecular KS relations show higher SFRs, lower scatter, and higher correlations, with steeper (1.21), and flatter slopes (0.96, 0.58) respectively. The shape of the SRs including metallicity, stellar mass, and gas fraction are flat, with an average value of 12+log(O/H) $\sim$ 8.12 dex. The baryonic mass vs effective oxygen yields, and the stellar, gas and baryonic mass vs SFE show higher dispersions and lower correlations. Since we use the dust mass as a tracer of gas mass, we derive the Dust-to-Gas Ratio and the CO luminosity-to-molecular gas mass conversion factors, showing differences of 0.16 and 0.95 dex for the total and molecular gas surface density, respectively, in comparison to previously reported values. We use a self regulated feedback model to conclude that stellar feedback plays an important role generating outflows in NGC 1569.

According to the $\Lambda$CDM cosmology, present-day galaxies with stellar masses $M_\star>10^{11} {\rm M}_\odot$ should contain a sizable fraction of dark matter within their stellar body. Models indicate that in massive early-type galaxies (ETGs) dark matter should account for $\sim60\%$ of the dynamical mass within five effective radii ($5 R_{\rm e}$). Most massive ETGs have been shaped through a two-phase process: the rapid growth of a compact core was followed by the accretion of an extended envelope through mergers. The exceedingly rare galaxies that have avoided the second phase, the so-called relic galaxies, are thought to be the frozen remains of the massive ETG population at $z\gtrsim2$. The best relic galaxy candidate discovered to date is NGC 1277, in the Perseus cluster. We used deep integral field GCMS data to revisit NGC 1277 out to an unprecedented radius of 6 kpc (corresponding to $5 R_{\rm e}$). By using Jeans anisotropic modelling we find a negligible dark matter fraction within $5 R_{\rm e}$ ($f_{\rm DM}(5 R_{\rm e})<0.05$; two-sigma confidence level), which is in tension with the expectation. Since the lack of an extended envelope would reduce dynamical friction and prevent the accretion of an envelope, we propose that NGC 1277 lost its dark matter very early or that it was dark matter deficient ab initio. We discuss our discovery in the framework of recent proposals suggesting that some relic galaxies may result from dark matter stripping as they fell in and interacted within galaxy clusters. Alternatively, NGC 1277 might have been born in a high-velocity collision of gas-rich proto-galactic fragments, where dark matter left behind a disc of dissipative baryons. We speculate that the relative velocities of $\approx2000 {\rm km/s}$ required for the latter process to happen were possible in the progenitors of the present-day rich galaxy clusters., Comment: Accepted for publication in A&A

NGC~6946, also known as the `Fireworks' galaxy, is an unusual galaxy that hosts a total of 225 supernova remnant (SNR) candidates, including 147 optically identified with high [SII]/Ha line ratios. In addition, this galaxy shows prominent HI holes, which were analyzed in previous studies. Indeed, the connection between SNRs and HI holes together with their physical implications in the surrounding gas is worth of attention. This paper explores the connection between the SNRs and the HI holes, including an analysis of their physical link to observational optical properties inside and around the rims of the holes, using new integral field unit (IFU) data from the Metal-THINGS survey. We present an analysis combining previously identified HI holes, SNRs candidates, and new integral field unit (IFU) data from Metal-THINGS of the spiral galaxy NGC 6946. We analyze the distributions of the oxygen abundance, star formation rate surface density, extinction, ionization, diffuse ionized gas, and the Baldwin-Phillips-Terlevich classification throughout the galaxy. By analyzing in detail the optical properties of the 121 previously identify HI holes in NGC 6946, we find that the SNRs are concentrated at the rims of the HI holes. Furthermore, our IFU data shows that the star formation rate and extinction are enhanced at the rims of the holes. To a lesser degree, the oxygen abundance and ionization parameter show hints of enhancement on the rims of the holes. Altogether, this provides evidence of induced star formation taking place at the rims of the holes, whose origin can be explained by the expansion of superbubbles created by multiple supernova explosions in large stellar clusters dozens of Myr ago., Comment: Accepted by A&A

With the recent administration change in Mexico, the fluctuations in national energy policy have generated widespread concerns among investors and the public. The debate centers around Mexico's energy dependence on the US and how Mexico's energy development should move forward. The goal of this study is two-fold. We first review the history and background of the recent energy reforms in Mexico. The focus of the study is on quantifying the state-level regional economic impact of the growing US-Mexico natural gas trade in Mexico. We examine both the quantity effect (impact of import volume) and the price effect (impact of natural gas price changes). Our empirical analysis adopts a fixed-effects regression model and the instrumental variables (IV) estimation approach to address spatial heterogeneities and the potential endogeneity associated with natural gas import. The quantity effect analysis suggests a statistically significant positive employment impact of imports in non-mining sectors. The impact in the mining sector, however, is insignificant. The state-level average (non-mining) employment impact is 127 jobs per million MCFs of natural gas imported from the US. The price effect analysis suggests a statistically significant positive employment impact of price increases in the mining sector. A one-percentage increase in natural gas price (1.82 Pesos/GJ, in 2015 Peso) leads to an average state-level mining employment increase of 140 (or 2.38%). We also explored the implications of our findings for Mexico's energy policy, trade policy, and energy security., Comment: 32 pages, 6 tables, 5 figures, with an appendix at the end

Social media provides an essential platform for shaping and sharing opinions and consuming information in a decentralized way. However, users often interact with and are exposed to information mostly aligned with their beliefs, creating a positive feedback mechanism that reinforces those beliefs and excludes contrasting ones. In this paper, we study such mechanisms by analyzing the social network dynamics of controversial Twitter discussions using unsupervised methods that demand little computational power. Specifically, we focus on the retweet networks of the climate change conversation during 2019, when important climate social movements flourished. We find echo chambers of climate believers and climate skeptics that we identify based solely on the retweeting patterns of Twitter users. In particular, we study the information sources, or chambers, consumed by the audience of the leading users of the conversation. Users with similar (contrasting) ideological positions show significantly high (low)-overlapping chambers, resulting in a bimodal overlap distribution. Further, we uncover the ideological position of previously unobserved high-impact users based on how many audience members fall into either echo chamber. We uncover the ideology of more than half of the retweeting population as either climate believers or skeptics and find that the cross-group communication is small. Moreover, we find that, while the echo chamber structures are consistent throughout the year, most users inside the echo chambers change from one week to the next, suggesting that they are a stable emergent property of the Twittersphere. Interestingly, we detect a significant decrease in polarization and a significant increase on the number of climate skeptics that coincides with the main #FridaysForFuture strikes during September, 2019., Comment: 25 pages (17 of main text + 8 of appendices), 11 figures

In this paper, we carry out a travelling-wave analysis of a model of tumour invasion with degenerate, cross-dependent diffusion. We consider two types of invasive fronts of tumour tissue into extracellular matrix (ECM), which represents healthy tissue. These types differ according to whether the density of ECM far ahead of the wave front is maximal or not. In the former case, we use a shooting argument to prove that there exists a unique travelling wave solution for any positive propagation speed. In the latter case, we further develop this argument to prove that there exists a unique travelling wave solution for any propagation speed greater than or equal to a strictly positive minimal wave speed. Using a combination of analytical and numerical results, we conjecture that the minimal wave speed depends monotonically on the degradation rate of ECM by tumour cells and the ECM density far ahead of the front., Comment: 41 pages (21 for the main paper, 17 for the supplementary material and 3 for the bibliography) with 6 figures (4 in the main paper and 2 in the supplementary material)