Geohazard assessment of Mexico City's Metro system derived from SAR interferometry observations.

Land subsidence rates in Mexico City reach 500 mm/year, causing progressive damage to the city's core infrastructure, including the Metro system. A deadly overpass collapse in 2021, along a Metro line that had operated for less than 10 years, brought subsidence-related structural damage to the attention of the system's authorities and led to major repairs to two of the twelve Metro lines. Still, the need for quantifying the magnitude and extent of subsidence affecting the Metro system's widespread infrastructure prevails. Using a wealth of satellite radar interferometry observations, levelling surveys, subsurface profiles, linear gradient and differential displacement analyses, and structural-engineering parameters, we assess the vulnerability of the Metro system's street-level and elevated segments to land subsidence. Our results reveal that high subsidence velocity gradients occur over sharp transitional zones between stable and fast-subsiding areas, reaching values of 1 × 10 - 3 year - 1 , resulting in slope changes up to 3.5% over a 20-year period and differential displacements between columns. Our findings suggest locations where the consequences of subsidence have compromised the train's braking safety design, increased railway flooding hazard, produced railway bending, and reduced the conceived 50-year service life of the Metro's elevated overpasses.

Country-scale assessment of urban areas, population, and households exposed to land subsidence using Sentinel-1 InSAR, and GPS time series.

The increased need for water resources in urban sprawls and intense droughts has forced more aggressive groundwater extraction resulting in numerous urban areas undergoing land subsidence. In most cases, only some large metropolitan areas have been well-characterized for subsidence. However, there is no existing country-wide assessment of urban areas, population, and households exposed to this process. This research showcases a methodology to systematically evaluate urban localities with land subsidence higher than - 2.8 cm/year throughout Mexico. We used Interferometric Synthetic Aperture Radar (InSAR) tools with a dataset of 4611 scenes from European Space Agency's Sentinel-1 A/B SAR sensors acquired from descending orbits from September 2018 through October 2019. This dataset was processed at a supercomputer using InSAR Scientific Computing Environment and the Miami InSAR Time Series software in Python software. The quality and calibration of the resulting velocity maps are assessed through a large-scale comparison with observations from 100 continuous GPS sites throughout Mexico. Our results show that an urban area of 3797 km2, 6.9 million households, and 17% of the total population in Mexico is exposed to subsidence velocities of faster than - 2.8 cm/year, in more than 853 urban localities within 29 land subsidence regions. We also confirm previous global potential estimations of subsidence occurrence in low relief areas over unconsolidated deposits and where groundwater aquifers are under stress. The presented research demonstrates the capabilities for surveying urban areas exposed to land subsidence at a country-scale level by combining Sentinel-1 velocities with spatial national census data. Supplementary Information: The online version contains supplementary material available at 10.1007/s11069-023-06259-5.

Prediction model for in-hospital mortality in patients at high altitudes with ARDS due to COVID-19.

INTRODUCTION: The diagnosis of acute respiratory distress syndrome (ARDS) includes the ratio of pressure arterial oxygen and inspired oxygen fraction (P/F) ≤ 300, which is often adjusted in locations more than 1,000 meters above sea level (masl) due to hypobaric hypoxemia. The main objective of this study was to develop a prediction model for in-hospital mortality among patients with ARDS due to coronavirus disease 2019 (COVID-19) (C-ARDS) at 2,600 masl with easily available variables at patient admission and to compare its discrimination capacity with a second model using the P/F adjusted for this high altitude. METHODS: This study was an analysis of data from patients with C-ARDS treated between March 2020 and July 2021 in a university hospital located in the city of Bogotá, Colombia, at 2,600 masl. Demographic and laboratory data were extracted from electronic records. For the prediction model, univariate analyses were performed to screen variables with p <0.25. Then, these variables were automatically selected with a backward stepwise approach with a significance level of 0.1. The interaction terms and fractional polynomials were also examined in the final model. Multiple imputation procedures and bootstraps were used to obtain the coefficients with the best external validation. In addition, total adjustment of the model and logistic regression diagnostics were performed. The same methodology was used to develop a second model with the P/F adjusted for altitude. Finally, the areas under the curve (AUCs) of the receiver operating characteristic (ROC) curves of the two models were compared. RESULTS: A total of 2,210 subjects were included in the final analysis. The final model included 11 variables without interaction terms or nonlinear functions. The coefficients are presented excluding influential observations. The final equation for the model fit was g(x) = age(0.04819)+weight(0.00653)+height(-0.01856)+haemoglobin(-0.0916)+platelet count(-0.003614)+ creatinine(0.0958)+lactate dehydrogenase(0.001589)+sodium(-0.02298)+potassium(0.1574)+systolic pressure(-0.00308)+if moderate ARDS(0.628)+if severe ARDS(1.379), and the probability of in-hospital death was p (x) = e g (x)/(1+ e g (x)). The AUC of the ROC curve was 0.7601 (95% confidence interval (CI) 0.74-0, 78). The second model with the adjusted P/F presented an AUC of 0.754 (95% CI 0.73-0.77). No statistically significant difference was found between the AUC curves (p value = 0.6795). CONCLUSION: This study presents a prediction model for patients with C-ARDS at 2,600 masl with easily available admission variables for early stratification of in-hospital mortality risk. Adjusting the P/F for 2,600 masl did not improve the predictive capacity of the model. We do not recommend adjusting the P/F for altitude.

Clinical characteristics and mortality associated with COVID-19 at high altitude: a cohort of 5161 patients in Bogotá, Colombia.

BACKGROUND: There are few data on the clinical outcomes of patients with coronavirus disease 2019 (COVID-19) in cities over 1000 m above sea level (masl). OBJECTIVES: To describe the clinical characteristics and mortality of patients with COVID-19 treated at a high complexity hospital in Bogotá, Colombia, at 2640 masl. METHODS: This was an observational study of a cohort including 5161 patients with confirmed COVID-19 infection from 19 March 2020 to 30 April 2021. Demographic data, laboratory values, comorbidities, oxygenation indices, and clinical outcomes were collected. Data were compared between survivors and nonsurvivors. An independent predictive model was performed for mortality and invasive mechanical ventilation (IMV) using classification and regression trees (CART). RESULTS: The median cohort age was 66 years (interquartile range (IQR) 53-77), with 1305 patients dying (25%) and 3856 surviving (75%). The intensive care unit (ICU) received 1223 patients (24%). Of 898 patients who received IMV, 613 (68%) of them perished. The ratio of partial pressure arterial oxygen (PaO2) to fraction inspired oxygen (FiO2), or the P/F ratio, upon ICU admission was 105 (IQR 77-146) and 137 (IQR 91-199) in the deceased and survivors, respectively. The CART model showed that the need for IMV, age greater than 79 years, ratio of oxygen saturation (SaO2) to FiO2, or the S/F ratio, less than 259, and lactate dehydrogenase (LDH) greater than 617 U/L at admission were associated with a greater probability of death. CONCLUSION: Among more than 5000 patients with COVID-19 treated in our hospital, mortality at hospital discharge was 25%. Older age, low S/F ratio, and high LDH at admission were predictors of mortality.

Detecting differential ground displacements of civil structures in fast-subsiding metropolises with interferometric SAR and band-pass filtering.

Ground displacements due to changes in soil conditions represent a threat to the stability of civil structures in many urban areas, worldwide. In fast-subsiding areas, regional subsidence (wavelength ~ 1,000's m) can be dominantly high and, consequently, mask other signals at local scales (wavelength ~ 10-100's m). Still, engineering and construction applications require a comprehensive knowledge of local-scale signals, which can threaten the stability of buildings and infrastructure. Here we present a new technique based on band-pass filters for uncovering local-scale signals hidden by regional subsidence as detected by interferometric SAR measurements. We apply our technique to a velocity field calculated from 21 high-resolution COSMO-SkyMed scenes acquired over Mexico City and obtain components of long (> 478 m), intermediate (42-478 m) and short (< 42 m) spatial wavelengths. Our results reveal that long-wavelength velocities exceed - 400 mm/year, whereas intermediate- and short-wavelength velocities are in the order of ± 15 mm/year. We show that intermediate-wavelength velocities are useful for retrieving signals such as uplift along elevated viaducts of Metro lines 4 and B, as well as differential displacements in Pantitlán station's pedestrian overpass system and across sharp geotechnical boundaries in the piedmont of Sierra de Santa Catarina-where surface faulting occurs.

Ultrasound-guided insertion of intra-aortic balloon counterpulsation in intensive care: description of the technique.

Intra-aortic balloon counterpulsation (IAoBC) is a mechanical circulatory support device that has been used for more than 50 years, mainly for cardiogenic shock. Although its effect on mortality is controversial, IAoBC is still used in a wide variety of pre- and postoperative clinical settings in cardiac surgery centers. IAoBC has a complication rate of approximately 30%, mostly associated with problems during insertion and malpositioning. Thus, an insertion technique based on the use of ultrasound at the patient's bedside in the intensive care unit (ICU) is proposed.

Real-time ultrasound-guided thoracentesis in the intensive care unit: prevalence of mechanical complications.

BACKGROUND: The use of thoracic ultrasound during thoracentesis reduces complications. The aim of this study was to determine the prevalence of complications for real-time ultrasound-guided thoracentesis performed by intensivists. As a secondary objective, the change in oxygenation before and after the procedure was evaluated. PATIENTS AND METHODS: An observational prospective study was conducted. A total of 81 cases of real-time ultrasound-guided thoracentesis performed by intensivists in the intensive care unit (ICU) of Méderi Major University Hospital, Bogotá, Colombia, between August 2018 and August 2019 were analyzed. Thoracentesis performed by interventional radiologists and using techniques different from the focus of this study were excluded from the analysis. RESULTS: There was one pneumothorax, for a prevalence rate of mechanical complications in this population of 1.2%. The mean partial oxygen pressure to inspired oxygen fraction ratio (PaO2/FiO2) prior to the procedure was 198.1 (95% CI 184.75-211.45), with a PaO2/FiO2 after the procedure of 224.6 (95% CI 213.08-226.12) (p < 0.05). CONCLUSIONS: Real-time ultrasound-guided thoracentesis performed by intensivists is a safe procedure and leads to a significant improvement in oxygenation rates. Future studies are required to determine the impact of these results on other outcomes, such as mortality, ICU stay, and days of mechanical ventilation.

MnO-labeled cells: positive contrast enhancement in MRI.

Manganese oxide (MnO) nanoparticles have been suggested as a promising "positive" MRI contrast agent for cellular and molecular studies. Mn-based contrast agents could enable T(1)-weighted quantitative cell tracking procedures in vivo based on signal enhancement. In this study, ultrasmall MnO particles were synthesized and coated with thiolated molecules (DMSA) and polyethylene glycol (PEG) to allow enhanced cell labeling properties and colloidal stability. This coating allowed the fabrication of individual ultrasmall nanoparticles of MnO (USPMnO) as well as of nanoaggregates of the same material (SPMnO). Particle size was measured by TEM and DLS. Physico-chemical properties were characterized by XPS and FTIR. The relaxometric properties of these aqueous suspensions were measured at various magnetic fields. The suspensions provided strong positive contrast enhancement in T(1)-weighted imaging due to high longitudinal relaxivities (r(1)) and low r(2)/r(1) ratios (USPMnO: r(1) = 3.4 ± 0.1 mM(-1)s(-1), r(2)/r(1) = 3.2; SPMnO: r(1) = 17.0 ± 0.5 mM(-1)s(-1), r(2)/r(1) = 4.0, at 1.41T). HT-1080 cancer cells incubated with the contrast agents were clearly visualized in MRI for Mn contents >1.1 pg Mn/cell. The viability of cells was not affected, contrarily to cells labeled with an equivalent concentration of Mn(2+) ions. A higher signal per cell was found for SPMnO-labeled compared with USPMnO-labeled cells, due to the higher relaxometric properties of the agglomerates. As a result, the "positive" signal enhancement effect is not significantly affected upon agglomeration of MnO particles in endosomes. This is a major requirement in the development of reliable cell tracking procedures using T(1)-weighted imaging sequences. This study confirms the potential of SPMnO and USPMnO to establish more quantitative cell tracking procedures with MRI.

Image segmentation of biofilm structures using optimal multi-level thresholding.

The appreciation of biofilm structures in digital images can be subjective to the observer, and hence it is necessary to analyse the underlying images in useful parameters by means of quantification that is, ideally, free of errors. This paper proposes a combination of techniques for segmentation of biofilm images through an optimal multi-level thresholding algorithm and a set of clustering validity indices, including the determination of the best number of thresholds. The results, which are validated through Rand Index and a quantification process performed in a laboratory, are similar to the quantification and segmentation done by an expert.

Electrochemical behavior of copper complexes with substituted polypyridinic ligands: an experimental and theoretical study.

Experimental redox potentials of the couples [Cu(R-L ( n ))(CH 3CN)] (2+,+), where L (1) is bis-(pyridine-2-ylmethyl)-benzylamine, L (2) is (pyridine-2-ylethyl)(pyridine-2-ylmethyl)-benzylamine, and R is H, Me, or CF 3, were determined in dichloromethane solution. The compounds exhibited one simple quasi-reversible wave over the measured potential range of -500 to +1200 mV, and the E 1/2 values varied from +200 to +850 mV versus SCE. These experimental values were correlated with redox potentials calculated using density functional theory. The optimized geometries and the predicted redox potentials were obtained using the BP86 functional and a combination of the basis sets LACV3P** (for Cu) and cc-pVTZ(-f) (for light atoms). A distortion analysis of all of the optimized geometries for both oxidation states was performed using the generalized interconversion coordinate phi. A linear relation was obtained between this parameter and the redox potentials. However, the [Cu(CF 3-L (1))(CH 3CN)] (+) complex showed the largest deviation, which was explained by the more-rigid structure of the ligand.

Di-u-hydroxo-bis{(acetonitrile)dibenzyl(6-methyl-2-pyridylmethyl)-amine-kappa2N,N]copper(II)} bis(perchlorate).

The title compound corresponds to a copper(II) dimer, [Cu2(OH)2(C2H3N)2(C21H22N2)2](ClO4)2, where the metal centres are mu2-bridged by hydroxo groups. The coordination of each copper(II) centre is a slightly distorted square-based pyramid, with two N atoms from dibenzyl(6-methyl-2-pyridylmethyl)amine (BiBzMePMA) and two hydroxo O atoms occupying the basal positions, and the acetonitrile N atom at the apical position. The dimer is centrosymmetric, with a crystallographic inversion centre midway between the two Cu atoms [Cu...Cu = 2.9522 (9) A].

Binuclear copper(II) oxidation products from copper(I) complexes with tridentate ligands. Magnetostructural characterization.

The bis-pyridine tridentate ligands (6-R-2-pyridylmethyl)-(2-pyridylmethyl) benzylamine (RDPMA, where R = CH(3), CF(3)), (6-R-2-pyridylmethyl)-(2-pyridylethyl) benzylamine (RPMPEA, where R = CH(3), CF(3)), and the bidentate ligand di-benzyl-(6-methyl-2-pyridylmethyl)amine (BiBzMePMA) have been synthesized and their copper(I) complexes oxidized in a methanol solution to afford self-assembled bis-micro-methoxo-binuclear copper(II) complexes (1, 2, 4, 6) or hydroxo- binuclear copper(II) complexes (3). Oxidation of the nonsubstituted DPMA (R = H) in dichloromethane gives a chloride-bridged complex (5). The crystal structures for [Cu(MeDPMA)(MeO)](2)(ClO(4))(2) (1), [Cu(RPMPEA)(MeO)](2)(ClO(4))(2) (for 2, R= Me, and for 4, R = CF(3)), [Cu(BiBzMePMA)(MeO)](2)(ClO(4))(2) (6), [Cu(FDPMA)(OH)](2)(ClO(4))(2) (3), and [Cu(DPMA)(Cl)](2)(ClO(4))(2) (5) have been determined, and their variable-temperature magnetic susceptibility has been measured in the temperature range of 10-300 K. The copper coordination geometries are best described as square pyramidal, except for 6, which is square planar, because of the lack of one pyridine ring in the bidentate ligand. In 1-4 and 6, the basal plane is formed by two pyridine N atoms and two O atoms from the bridging methoxo or hydroxo groups, whereas in 5, the bridging Cl atoms occupy axial-equatorial sites. Magnetic susceptibility measurements show that the Cu atoms are strongly coupled antiferromagnetically in the bis-methoxo complexes 1, 2, 4, and 6, with -2J > 600 cm(-)(1), whereas for the hydroxo complex 3, -2J = 195 cm(-)(1) and the chloride-bridged complex 5 shows a weak ferromagnetic coupling, with 2J = 21 cm(-)(1) (2J is an indicator of the magnetic interaction between the Cu centers).

Decreased dendritic spine density on prefrontal cortical and hippocampal pyramidal neurons in postweaning social isolation rats.

The effects of postweaning social isolation (pwSI) on the morphology of the pyramidal neurons from the medial part of the prefrontal cortex (mPFC) and hippocampus were investigated in rats. The animals were weaned on day 21 postnatal (P21) and isolated 8 weeks. After the isolation period, locomotor activity was evaluated through 60 min in the locomotor activity chambers and the animals were sacrificed by overdoses of sodium pentobarbital and perfused intracardially with 0.9% saline solution. The brains were removed, processed by the Golgi-Cox stain and analyzed by the Sholl method. The locomotor activity in the novel environment from the isolated rats was increased with respect to the controls. The dendritic morphology clearly showed that the pwSI animals presented a decrease in dendritic length of pyramidal cells from the CA1 of the hippocampus without changes in the pyramidal neurons of the mPFC. However, the density of dendritic spines was decreased in the pyramidal cells from mPFC and Hippocampus. In addition, the Sholl analyses showed that pwSI produced a decrease in the number of sholl intersections compared with the control group only in the hippocampus region. The present results suggest that pwSI may in part affect the dendritic morphology in the limbic structures such as mPFC and hippocampus that are implicated in schizophrenia.

Un modelo neurobiológico de la mente / A neurobiological model of mind

Los autores estabelecen una diferencia esencial entre las regiones dorsal y ventral de la corteza cerebral. Mientras la corteza dorsal -ligada al arquicortex o allocrotex hipocámpico -elabora los actos y los objetos utilizados por los actos, la corteza ventral -vinculada con el paleocortex o allocortex ofatorio - construye valores preventivos que posibilitan la inhibición de los actos cuando la utilización de objetos puede resultar peligrosa. Esta distinción entre regiones dorsal y ventral de la corteza cerebral está sustentada, sobre todo, en los síndromes de desinhibición que surgen en pacientes con lesiones ventrales y, además, puede explicar algunas manifestaciones de desinhibición que integran el cuadro de la esquizofrenia

Un modelo neurobiológico de la mente / A neurobiological model of mind

Los autores estabelecen una diferencia esencial entre las regiones dorsal y ventral de la corteza cerebral. Mientras la corteza dorsal -ligada al arquicortex o allocrotex hipocámpico -elabora los actos y los objetos utilizados por los actos, la corteza ventral -vinculada con el paleocortex o allocortex ofatorio - construye valores preventivos que posibilitan la inhibición de los actos cuando la utilización de objetos puede resultar peligrosa. Esta distinción entre regiones dorsal y ventral de la corteza cerebral está sustentada, sobre todo, en los síndromes de desinhibición que surgen en pacientes con lesiones ventrales y, además, puede explicar algunas manifestaciones de desinhibición que integran el cuadro de la esquizofrenia (AU)

Apraxia ideatoría en la psicosis confusional / Ideational apraxia in confusional psychosis

La apraxia ideatoria de Pick siempre ha sido una cuestión de los neurólogos, pues es una de las manifestaciones permanentes de las lesiones cerebrales localizadas en el territorio posterior del hemisferio izquierdo. Pero, además, la apraxia ideatoria puede aparecer, junto con los falsos reconocimientos y la desorientación espacial, integrando las manifestaciones transitorias de la psicosis confusional. Parece legítimo incorporar la apraxia ideatoria entre los síntomas que deben buscarse en los estados psicoticos cicloides que incluyen la psicosis confusional. De esta manera la apraxia de Pick es también una cuestión de los psiquiatras.

Apraxia ideatoría en la psicosis confusional / Ideational apraxia in confusional psychosis

La apraxia ideatoria de Pick siempre ha sido una cuestión de los neurólogos, pues es una de las manifestaciones permanentes de las lesiones cerebrales localizadas en el territorio posterior del hemisferio izquierdo. Pero, además, la apraxia ideatoria puede aparecer, junto con los falsos reconocimientos y la desorientación espacial, integrando las manifestaciones transitorias de la psicosis confusional. Parece legítimo incorporar la apraxia ideatoria entre los síntomas que deben buscarse en los estados psicoticos cicloides que incluyen la psicosis confusional. De esta manera la apraxia de Pick es también una cuestión de los psiquiatras. (AU)