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"Rodriguez, E"
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The Mother's Day Geomagnetic Storm on 10 May 2024: Aurora Observations and Low Latitude Space Weather Effects in Mexico
On 10 May 2024, a severe geomagnetic storm coinciding with Mother's Day in Mexico lasted over 40 hr and produced polar auroras observable at low latitudes. This storm, the most intense since 2003, resulted from a series of solar flares and coronal mass ejections from active region 3664. The event was significant for space weather studies in Mexico, marking a milestone by enabling comprehensive measurements of its effects. The Mexico Space Weather Service (SCIESMEX) and the National Space Weather Laboratory (LANCE) had prepared for such an event since their inception. LANCE's instrument networks recorded solar chromospheric images, solar radio bursts, geomagnetic variations, Schumann resonances, ionospheric disturbances, and energetic particle flows. They also monitored Geomagnetically Induced Currents (GICs) in three strategic substations of the national electrical system. This provided unprecedented insights into the dynamics of severe space weather events at the North‐American low‐latitude environment. Citizen science efforts documented auroras and regional responses, capturing variations in geomagnetic indices, ionospheric disturbances, cosmic ray fluxes, GICs, and technological impacts. SCIESMEX worked with the National Civil Protection System (SINAPROC) to issue warnings, ensuring public awareness and preparedness. This coordination underscores the importance of effective communication and collaboration in mitigating impacts. The May 2024 geomagnetic storm demonstrated the critical role of preparedness, research, and public education in reducing the effects of future space weather events in Mexico.
Journal Article
Estimation of salt intake assessed by urinary excretion of sodium over 24 h in Spanish subjects aged 7–11 years
Purpose
High intake of salt is associated with early development of cardiovascular risk factors (e.g., hypertension, obesity). In “developed” countries, individuals frequently exceed dietary recommendations for salt intake. Taking into account the limited data on sodium intake by 24-h excretion in urine in schoolchildren, we wished to determine baseline salt intake in Spanish subjects aged 7–11 years.
Methods
The present study was an observational study involving 205 schoolchildren (109 boys and 96 girls) selected from various Spanish provinces. Sodium intake was ascertained by measuring sodium excretion in urine over 24 h. Creatinine was used to validate completeness of urine collections. The correlation between fat-free mass determined by anthropometry and that determined via urinary excretion of creatinine was calculated (
r
= 0.651;
p
< 0.001).
Results
Mean 24-h urinary excretion of sodium was 132.7 ± 51.4 mmol/24 h (salt equivalent: 7.8 ± 3.1 g/day). Hence, 84.5 % of subjects aged ≤10 years had intakes of >4 g salt/day, and 66.7 % of those aged >10 years had intakes of >5 g salt/day. Urinary excretion of sodium was correlated with systolic blood pressure and diastolic blood pressure (
r
= 0.1574 and
r
= 0.1400, respectively). Logistic regression analyses, adjusted by sex, showed that a high body mass index (odds ratio = 1.159; 95 % CI 1.041–1.290;
p
< 0.05) was associated with an increased likelihood of high urinary excretion of sodium.
Conclusions
Sodium intake, as estimated by 24-h urinary excretion, was (on average) higher than recommended. Reducing the sodium content children’s diet is a sound policy to reduce cardiovascular risk.
Journal Article
Reactive Oxygen Species (ROS) Regulates Different Types of Cell Death by Acting as a Rheostat
Reactive oxygen species (ROS) are essential for cellular signaling and response to stress. The level of ROS and the type of ROS determine the ability of cells to undergo cell death. Furthermore, dysregulation of the antioxidant pathways is associated with many diseases. It has become apparent that cell death can occur through different mechanisms leading to the classifications of different types of cell death such as apoptosis, ferroptosis, and necroptosis. ROS play essential roles in all forms of cell death, but it is only now coming into focus that ROS control and determine the type of cell death that occurs in any given cell. Indeed, ROS may act as a rheostat allowing different cell death mechanisms to be engaged and crosstalk with different cell death types. In this review, we will describe the ROS regulatory pathways and how they control different types of cell death under normal and disease states. We will also propose how ROS could provide a mechanism of crosstalk between cell death mechanisms and act as a rheostat determining the type of cell death.
Journal Article
Effect of the Nano Crystal Size on the X-ray Diffraction Patterns of Biogenic Hydroxyapatite from Human, Bovine, and Porcine Bones
This paper focuses on the study of the effect of the change of the crystal size on the shape and width of the X-ray diffraction patterns for defatted and deproteinized bones as well as incinerated biogenic hydroxyapatite obtained from bovine, porcine, and human bones. Inductively Couple Plasma showed the presence of some ions such as Mg, K, Al, Fe, Zn, and Na for all samples. The nanometric size of the crystals was determined through High Resolution Transmission Electron Microscopy in which ordered crystals were found. The calcination of raw clean bones at 720 °C produced a transition of crystal size from nano to micro due to a coalescence phenomenon, this was accompanied by a decrease of the peak width of the X-ray diffraction patterns due to the decrease of the inelastic scattering contribution from the microcrystals. A simulation of the effect of the crystallite size on the shape and width of the X-ray patterns was done using PDF-4 software which confirmed that raw ordered bone crystals produce broad peaks which so far have been erroneously assigned to polycrystalline hydroxyapatite with low crystalline quality.
Journal Article
Controlled patterning of crystalline domains by frontal polymerization
Materials with hierarchical architectures that combine soft and hard material domains with coalesced interfaces possess superior properties compared with their homogeneous counterparts
1
,
2
,
3
–
4
. These architectures in synthetic materials have been achieved through deterministic manufacturing strategies such as 3D printing, which require an a priori design and active intervention throughout the process to achieve architectures spanning multiple length scales
5
,
6
,
7
,
8
–
9
. Here we harness frontal polymerization spin mode dynamics to autonomously fabricate patterned crystalline domains in poly(cyclooctadiene) with multiscale organization. This rapid, dissipative processing method leads to the formation of amorphous and semi-crystalline domains emerging from the internal interfaces generated between the solid polymer and the propagating cure front. The size, spacing and arrangement of the domains are controlled by the interplay between the reaction kinetics, thermochemistry and boundary conditions. Small perturbations in the fabrication conditions reproducibly lead to remarkable changes in the patterned microstructure and the resulting strength, elastic modulus and toughness of the polymer. This ability to control mechanical properties and performance solely through the initial conditions and the mode of front propagation represents a marked advancement in the design and manufacturing of advanced multiscale materials.
Frontal polymerization spin mode dynamics is used to autonomously fabricate patterned crystalline domains in poly(cyclooctadiene) with multiscale organization.
Journal Article
Mitochondrial electron transport chain is necessary for NLRP3 inflammasome activation
The NLRP3 inflammasome is linked to sterile and pathogen-dependent inflammation, and its dysregulation underlies many chronic diseases. Mitochondria have been implicated as regulators of the NLRP3 inflammasome through several mechanisms including generation of mitochondrial reactive oxygen species (ROS). Here, we report that mitochondrial electron transport chain (ETC) complex I, II, III and V inhibitors all prevent NLRP3 inflammasome activation. Ectopic expression of Saccharomyces cerevisiae NADH dehydrogenase (NDI1) or Ciona intestinalis alternative oxidase, which can complement the functional loss of mitochondrial complex I or III, respectively, without generation of ROS, rescued NLRP3 inflammasome activation in the absence of endogenous mitochondrial complex I or complex III function. Metabolomics revealed phosphocreatine (PCr), which can sustain ATP levels, as a common metabolite that is diminished by mitochondrial ETC inhibitors. PCr depletion decreased ATP levels and NLRP3 inflammasome activation. Thus, the mitochondrial ETC sustains NLRP3 inflammasome activation through PCr-dependent generation of ATP, but via a ROS-independent mechanism.How the mitochondrial electron transport chain (ETC) interacts with the NLRP3 inflammasome is somewhat unclear. Here the authors use individual complex inhibitors and new genetic models to show that ETC is critical in providing ATP via the phosphocreatine shuttle to activate the NLRP3 inflammasome.
Journal Article
Polarized thermal emission from dust in a galaxy at redshift 2.6
Magnetic fields are fundamental to the evolution of galaxies, playing a key role in the astrophysics of the interstellar medium and star formation. Large-scale ordered magnetic fields have been mapped in the Milky Way and nearby galaxies
1
,
2
, but it is not known how early in the Universe such structures formed
3
. Here we report the detection of linearly polarized thermal emission from dust grains in a strongly lensed, intrinsically luminous galaxy that is forming stars at a rate more than 1,000 times that of the Milky Way at redshift 2.6, within 2.5 Gyr of the Big Bang
4
,
5
. The polarized emission arises from the alignment of dust grains with the local magnetic field
6
,
7
. The median polarization fraction is of the order of 1%, similar to nearby spiral galaxies
8
. Our observations support the presence of a 5-kiloparsec-scale ordered magnetic field with a strength of around 500 μG or lower, oriented parallel to the molecular gas disk. This confirms that such structures can be rapidly formed in galaxies, early in cosmic history.
Linearly polarized thermal emission from dust grains in a strongly lensed, intrinsically luminous galaxy forming stars at a rate more than 1,000 times that of the Milky Way is detected.
Journal Article
Understanding Accretion Variability through TESS Observations of Taurus
Interpreting the short-timescale variability of the accreting, young, low-mass stars known as Classical T Tauri stars remains an open task. Month-long, continuous light curves from the Transiting Exoplanet Survey Satellite (TESS) have become available for hundreds of T Tauri stars. With this vast data set, identifying connections between the variability observed by TESS and short-timescale accretion variability is valuable for characterizing the accretion process. To this end, we obtained short-cadence TESS observations of 14 T Tauri stars in the Taurus star formation region along with simultaneous ground-based, UBVRI-band photometry to be used as accretion diagnostics. In addition, we combine our data set with previously published simultaneous near-UV–near-IR Hubble Space Telescope spectra for one member of the sample. We find evidence that much of the short-timescale variability observed in the TESS light curves can be attributed to changes in the accretion rate, but note significant scatter between separate nights and objects. We identify hints of time lags within our data set that increase at shorter wavelengths, which we suggest may be evidence of longitudinal density stratification of the accretion column. Our results highlight that contemporaneous, multiwavelength observations remain critical for providing context for the observed variability of these stars.
Journal Article