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Ozone plays a key role in both atmospheric chemistry and UV absorption in planetary atmospheres. On Mars, upper-tropospheric ozone has been widely characterized by space-based instruments. However, surface ozone remains poorly characterized, hindered by the limited sensitivity of orbiters to the lowest scale height of the atmosphere and challenges in delivering payloads to the surface of Mars, which have prevented, to date, the measurement of ozone from the surface of Mars. Systematic measurements from the Martian surface could advance our knowledge of the atmospheric chemistry and habitability potential of this planet. NASA's Mars 2020 mission includes the first ozone detector deployed on the Martian surface, which is based on discrete photometric observations in the ultraviolet band, a simple technology that could obtain the first insights into total ozone abundance in preparation for more sophisticated measurement techniques. This paper describes the Mars 2020 ozone detector and its retrieval algorithm, including its performance under different sources of uncertainty and the potential application of the retrieval algorithm on other missions, such as NASA's Mars Science Laboratory. Pre-landing simulations using the UVISMART radiative transfer model suggest that the retrieval is robust and that it can deal with common issues affecting surface operations in Martian missions, although the expected low ozone abundance and instrument uncertainties could challenge its characterization in tropical latitudes of the planet. Other space missions will potentially include sensors of similar technology. [ABSTRACT FROM AUTHOR]

We present a quantitative analysis of the seasonal record of Uranus's disc-averaged colour and photometric magnitude in Strömgren b and y filters (centred at 467 and 551 nm, respectively), recorded at the Lowell Observatory from 1950 to 2016, and supplemented with HST /WFC3 observations from 2016 to 2022. We find that the seasonal variations of magnitude can be explained by the lower abundance of methane at polar latitudes combined with a time-dependent increase of the reflectivity of the aerosol particles in layer near the methane condensation level at 1 – 2 bar. This increase in reflectivity is consistent with the addition of conservatively scattering particles to this layer, for which the modelled background haze particles are strongly absorbing at both blue and red wavelengths. We suggest that this additional component may come from a higher proportion of methane ice particles. We suggest that the increase in reflectivity of Uranus in both filters between the equinoxes in 1966 and 2007, noted by previous authors, might be related to Uranus's distance from the Sun and the production rate of dark photochemical haze products. Finally, we find that although the visible colour of Uranus is less blue than Neptune, due to the increased aerosol thickness on Uranus, and this difference is greatest at Uranus's solstices, it is much less significant than is commonly believed due to a long-standing misperception of Neptune's 'true' colour. We describe how filter-imaging observations, such as those from Voyager-2/ISS and HST /WFC3, should be processed to yield accurate true colour representations. [ABSTRACT FROM AUTHOR]

Spatial release from masking (SRM) in speech-on-speech tasks has been widely studied in the horizontal plane, where interaural cues play a fundamental role. Several studies have also observed SRM for sources located in the median plane, where (monaural) spectral cues are more important. However, a relatively unexplored research question concerns the impact of head-related transfer function (HRTF) personalisation on SRM, for example, whether using individually-measured HRTFs results in better performance if compared with the use of mannequin HRTFs. This study compares SRM in the median plane in a speech-on-speech virtual task rendered using both individual and mannequin HRTFs. SRM is obtained using English sentences with non-native English speakers. Our participants show lower SRM performances compared to those found by others using native English participants. Furthermore, SRM is significantly larger when the source is spatialised using the individual HRTF, and this effect is more marked for those with lower English proficiency. Further analyses using a spectral distortion metric and the estimation of the better-ear effect, show that the observed SRM can only partially be explained by HRTF-specific factors and that the effect of the familiarity with individual spatial cues is likely to be the most significant element driving these results. [ABSTRACT FROM AUTHOR]

Juglans neotropica Diels (Walnut) is a highly desired species for the various products obtained from it. Its wood is considered fine and has different uses, which is why it is important to correctly identify the species; However, there are various descriptions that make its optimal identification difficult, so it was proposed, in addition to describing the anatomical (macroscopy) and organoleptic characteristics of the wood, but also, by comparison, determining the general characteristics of the species. The study was carried out in the province of Imbabura, northern Ecuador, the trees were selected based on the NTE INEN 1158 standard: the anatomical characteristics based on the IAWA list and the COPANT standard No. 30:1-019; while for the organoleptic characteristics the NTE INEN 1163 standard was used; It is worth mentioning that the Virtual Color Atlas digital resource was used for color; Furthermore, by comparison, the macroanatomical characteristics and general organoleptic properties of the wood were obtained. It was evident that the analyzed characteristics of Juglans neotropica Diels wood present differences in terms of descriptions, however general descriptors were determined to facilitate the identification of the wood. [ABSTRACT FROM AUTHOR]

Hubble Space Telescope Wide‐Field Camera 3 (HST/WFC3) observations spanning 2015 to 2021 confirm a brightening of Uranus' north polar hood feature with time. The vertical aerosol model of Irwin et al. (2023, https://doi.org/10.1038/s41550-023-02047-0) (IRW23), consisting of a deep haze layer based at ∼5 bar, a 1–2 bar haze layer, and an extended haze rising up from the 1–2 bar layer, was applied to retrievals on HST Space Telescope Imaging Spectrograph (STIS) (HST/STIS) observations (Sromovsky et al., 2014, 2019, https://doi.org/10.1016/j.icarus.2014.05.016, https://doi.org/10.1016/j.icarus.2018.06.026) revealing a reduction in cloud‐top CH4 volume mixing ratio (VMR) (i.e., above the deep ∼5 bar haze) by an average of 0.0019 ± 0.0003 between 40–80◦N (∼10% average reduction) from 2012 to 2015. A combination of latitudinal retrievals on the HST/WFC3 and HST/STIS data sets, again employing the IRW23 model, reveal a temporal thickening of the 1–2 bar haze layer to be the main cause of the polar hood brightening, finding an average increase in integrated opacity of 1.09 ± 0.08 (∼33% increase) at 0.8 µm north of ∼45°N, concurrent with a decrease in the imaginary refractive index spectrum of the 1–2 bar haze layer north of ∼40°N and longwards of ∼0.7 µm. Small contributions to the brightening were found from a thickening of the deep aerosol layer, with an average increase in integrated opacity of 0.6 ± 0.1 (58% increase) north of 45°N between 2012 and 2015, and from the aforementioned decrease in CH4 VMR. Our results are consistent with the slowing of a stratospheric meridional circulation, exhibiting subsidence at the poles. Plain Language Summary: Uranus' north polar hood—a bright cap‐like feature encircling the northern polar region within its atmosphere—is observed to be brightening over time. Using several observations of Uranus captured between 2012 and 2021 by the Hubble Space Telescope, this study aims to pinpoint, for the first time, the specific changes occurring within the atmosphere leading to this evolution. Analysis of the observations confirmed the predominant cause of the hood's brightening to be changes in the scattering properties of the atmosphere's aerosol layers. A vertical aerosol model consisting of 3 distinct haze layers was employed to investigate these changes. We find that the hood's brightening mainly stems from changes in the middle haze layer in the model (centered at 1–2 bar), finding a thickening of this layer concurrent with an increase in the reflectivity of its aerosols over time at latitudes coincident with the north polar hood (∼45–90°N). Small contributions to the temporal brightening were also found from a ∼10% reduction in cloud‐top methane and a thickening of the deepest haze layer in the model (centered at ∼5 bar) at north polar hood latitudes. Key Points: We confirm that the brightening of Uranus' north polar hood is predominantly due to changes in aerosol scatteringA temporal thickening and increase in aerosol reflectivity of Irwin et al. (2023, https://doi.org/10.1038/s41550-023-02047-0)'s 1–2 bar haze is the main cause of the brighteningWe find a further reduction in polar cloud‐top methane over time from retrievals carried out on Hubble Space Telescope's/Space Telescope Imaging Spectrograph observations [ABSTRACT FROM AUTHOR]

The two upward‐looking Thermal InfraRed Sensor (TIRS) channels from the Mars Environmental Dynamics Analyzer (MEDA) instrument suite on board the Perseverance rover enable the retrieval of total aerosol optical depth (dust plus water ice cloud) above the rover for all observations when TIRS is taken. Because TIRS observes at thermal infrared wavelengths, the retrievals are possible during both the day and night and thus, they provide an excellent way to monitor both the diurnal and seasonal variations of aerosols above Jezero Crater. A retrieval algorithm has been developed for this purpose and here, we describe that algorithm along with our results for the first 400 sols of the Perseverance mission covering nearly the entire aphelion season as well as a regional dust storm and the beginning of the perihelion season. We find systematic diurnal variations in aerosol optical depth that can be associated with dust and water ice clouds as well as a clear change from a cloud‐filled aphelion season to a perihelion season where dust is the dominant aerosol. A comparison of retrieved optical depths between TIRS and the SkyCam camera that is also part of MEDA indicates evidence of possible diurnal variations in cloud height or particle size. Plain Language Summary: Observations made by the Thermal InfraRed Sensor (TIRS) instrument on the Perseverance rover enable the amount of airborne dust and clouds above the rover to be determined. The TIRS instrument observes thermal infrared radiation so it can observe the dust and clouds both during the day and night. Here, we present results for the first 13 months of observations by TIRS. These results show that the dust and clouds vary as a function of season on Mars and as a function of the time of day. At the beginning of the period of time studied here, there were more clouds than dust, and the clouds were maximum just before dawn and just after dusk. Later in the season, dust became the dominant aerosol, with the diurnal maximum near midday. Key Points: The Thermal InfraRed Sensor (TIRS) upward‐looking sensors enable the retrieval of total aerosol optical depth during both day and nightAerosol optical depth shows clear diurnal and seasonal trends. Diurnal maximum opacity is near dawn for clouds and near noon for dustTIRS retrievals of aerosol optical depth can detail the complex time history of rapidly changing events such as dust storms [ABSTRACT FROM AUTHOR]

The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features. [ABSTRACT FROM AUTHOR]

When performing binaural spatialisation, it is widely accepted that the choice of the head related transfer functions (HRTFs), and in particular the use of individually measured ones, can have an impact on localisation accuracy, externalization, and overall realism. Yet the impact of HRTF choices on speech-in-noise performances in cocktail party-like scenarios has not been investigated in depth. This paper introduces a study where 22 participants were presented with a frontal speech target and two lateral maskers, spatialised using a set of non-individual HRTFs. Speech reception threshold (SRT) was measured for each HRTF. Furthermore, using the SRT predicted by an existing speech perception model, the measured values were compensated in the attempt to remove overall HRTF-specific benefits. Results show significant overall differences among the SRTs measured using different HRTFs, consistently with the results predicted by the model. Individual differences between participants related to their SRT performances using different HRTFs could also be found, but their significance was reduced after the compensation. The implications of these findings are relevant to several research areas related to spatial hearing and speech perception, suggesting that when testing speech-in-noise performances within binaurally rendered virtual environments, the choice of the HRTF for each individual should be carefully considered. [ABSTRACT FROM AUTHOR]

We use ground‐based mid‐infrared (8–20 μm) data acquired by three different instruments between 2005 and 2008 to characterize the variability of tropospheric temperature and aerosol opacity during the 2006–2007 Equatorial Zone disturbance. This disturbance is part of a repeating pattern of cloud‐clearing events at Jupiter's equator, observed as a significant brightening at 5 μm (sensing the 2‐ to 7‐bar region) and darkening at visible wavelengths (sensing the ∼0.7‐bar pressure level). The data reveal a brightness temperature increase of ∼3.1 K between 2005 and February 2007 at 8.6‐μm sensing tropospheric aerosol opacity and temperature near 0.6–0.8 bar. At wavelengths sensing tropospheric ammonia and temperatures between 150 and 600 mbar, the brightness temperature remains largely invariant between 2005 and 2008. The tropospheric vertical temperature profile and the tropospheric aerosol opacity were derived from images captured in different filters on four different dates, one for each year. The retrieved aerosol opacity at ∼0.6–0.8 bar shows a decrease at 2–5°S of ∼45% in 2006 and ∼65% in 2007, with respect to 2008. This is consistent with cloud clearing/thinning during the coloration of the Equatorial Zone at visible wavelengths. This brightening at 8.6 μm started in 2005 and preceded the brightening at 5 μm, which started in April 2006. The results also suggest that cloud clearing during the Equatorial Zone disturbances is not simply the result of tropospheric warming, at least at p < 0.7 bar. We propose that cloud clearing occurs due to a decrease in the ammonia gas upwelling at the equator. Plain Language Summary: Jupiter's equatorial latitudes between ∼7°, known as the Equatorial Zone (EZ), undergo dramatic planetary‐scale disturbances that completely alter its appearance at different altitudes of the troposphere between 0.7 and 4 bar. Here we characterize the last EZ disturbance, observed in 2006–2007, to investigate what atmospheric conditions vary during these disturbances. Retrieved aerosol opacity at ∼0.6 bar shows a decrease at 2–5°S of ∼45% in 2006 and ∼65% in 2007, with respect to 2008, consistent with cloud clearing/thinning during these events. This removal of aerosol opacity is observed to start in 2005, a year before the deeper clouds are cleared. These results indicate that the EZ disturbance involves the clearing of both the ammonia ice cloud near 0.7 bar and the deeper NH4SH clouds with each cloud deck responding at different times. Results also suggest that cloud clearing during the EZ disturbances is not simply the result of tropospheric warming in the middle‐to‐high troposphere. We propose that cloud clearing occurs due to a decrease in the ammonia gas upwelling from deeper levels. Key Points: We characterize the 2006–2007 Equatorial Zone disturbance that completely altered the appearance of Jupiter's equatorial latitudesRetrieved aerosol opacity at ∼0.6 bar decreases by 45–65% at 2–5°S during the EZ disturbances, consistent with cloud clearing/thinningCloud clearing during the EZ disturbances is not simply the result of tropospheric warming, at least at p < 0.7 bar [ABSTRACT FROM AUTHOR]

Copyright of CorSalud is the property of Cardiocentro Ernesto Che Guevara and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: with the aging of the population an increasing number of patients attend consultation for acute abdominal symptoms that require timely and comprehensive care. Objective: to describe the causes and evolution of the acute surgical abdomen in the elderly. Methods: a descriptive observational study was carried out at the "Arnaldo Milián Castro" Hospital in the Province of Villa Clara from January 2017 to December 2018. The population consisted of 780 patients who entered the Surgery Services for acute abdomen. Sex, age, cause of acute surgical abdomen and post-surgical complications were study variables. Methods of descriptive statistics were used. The information was extracted from the medical records. Results: 54.2% were men and there was a predominance of the age group between 60 and 70 years. Complicated abdominal wall hernias were the disease with the highest incidence (34.7%), 81.4% of the adults who had undergone surgery had no post-surgical complications and mortality was 1.4%. Conclusions: the main causes of acute surgical abdomen in the elderly patient in this series were complicated abdominal wall herniation, acute appendicitis, intestinal occlusion and acute cholecystitis. There were low complications and mortality rates. The control of the acute surgical abdomen depends on the careful evaluation of the acute condition and the elective correction of known abdominal diseases. [ABSTRACT FROM AUTHOR]

Atmospheric circulation patterns derived from multi-spectral remote sensing can serve as a guide for choosing a suitable entry location for a future in situ probe mission to the Ice Giants. Since the Voyager-2 flybys in the 1980s, three decades of observations from ground- and space-based observatories have generated a picture of Ice Giant circulation that is complex, perplexing, and altogether unlike that seen on the Gas Giants. This review seeks to reconcile the various competing circulation patterns from an observational perspective, accounting for spatially-resolved measurements of: zonal albedo contrasts and banded appearances; cloud-tracked zonal winds; temperature and para-H2 measurements above the condensate clouds; and equator-to-pole contrasts in condensable volatiles (methane, ammonia, and hydrogen sulphide) in the deeper troposphere. These observations identify three distinct latitude domains: an equatorial domain of deep upwelling and upper-tropospheric subsidence, potentially bounded by peaks in the retrograde zonal jet and analogous to Jovian cyclonic belts; a mid-latitude transitional domain of upper-tropospheric upwelling, vigorous cloud activity, analogous to Jovian anticyclonic zones; and a polar domain of strong subsidence, volatile depletion, and small-scale (and potentially seasonally-variable) convective activity. Taken together, the multi-wavelength observations suggest a tiered structure of stacked circulation cells (at least two in the troposphere and one in the stratosphere), potentially separated in the vertical by (i) strong molecular weight gradients associated with cloud condensation, and by (ii) transitions from a thermally-direct circulation regime at depth to a wave- and radiative-driven circulation regime at high altitude. The inferred circulation can be tested in the coming decade by 3D numerical simulations of the atmosphere, and by observations from future world-class facilities. The carrier spacecraft for any probe entry mission must ultimately carry a suite of remote-sensing instruments capable of fully constraining the atmospheric motions at the probe descent location. [ABSTRACT FROM AUTHOR]

Since the observation of the great pleomorphism of fish trypanosomes, in vitro culture has become an important tool to support taxonomic studies investigating the biology of cultured parasites, such as their structure, growth dynamics, and cellular cycle. Relative to their biology, ex vivo and in vitro studies have shown that these parasites, during the multiplication process, duplicate and segregate the kinetoplast before nucleus replication and division. However, the inverse sequence (the nucleus divides before the kinetoplast) has only been documented for a species of marine fish trypanosomes on a single occasion. Now, this previously rare event was observed in Trypanosoma abeli, a freshwater fish trypanosome. Specifically, from 376 cultured parasites in the multiplication process, we determined the sequence of organelle division for 111 forms; 39% exhibited nucleus duplication prior to kinetoplast replication. Thus, our results suggest that nucleus division before the kinetoplast may not represent an accidental or erroneous event occurring in the main pathway of parasite reproduction, but instead could be a species‐specific process of cell biology in trypanosomes, such as previously noticed for Leishmania. This "alternative" pathway for organelle replication is a new field to be explored concerning the biology of marine and freshwater fish trypanosomes. [ABSTRACT FROM AUTHOR]

The 3D Tune-In Toolkit (3DTI Toolkit) is an open-source standard C++ library which includes a binaural spatialiser. This paper presents the technical details of this renderer, outlining its architecture and describing the processes implemented in each of its components. In order to put this description into context, the basic concepts behind binaural spatialisation are reviewed through a chronology of research milestones in the field in the last 40 years. The 3DTI Toolkit renders the anechoic signal path by convolving sound sources with Head Related Impulse Responses (HRIRs), obtained by interpolating those extracted from a set that can be loaded from any file in a standard audio format. Interaural time differences are managed separately, in order to be able to customise the rendering according the head size of the listener, and to reduce comb-filtering when interpolating between different HRIRs. In addition, geometrical and frequency-dependent corrections for simulating near-field sources are included. Reverberation is computed separately using a virtual loudspeakers Ambisonic approach and convolution with Binaural Room Impulse Responses (BRIRs). In all these processes, special care has been put in avoiding audible artefacts produced by changes in gains and audio filters due to the movements of sources and of the listener. The 3DTI Toolkit performance, as well as some other relevant metrics such as non-linear distortion, are assessed and presented, followed by a comparison between the features offered by the 3DTI Toolkit and those found in other currently available open- and closed-source binaural renderers. [ABSTRACT FROM AUTHOR]

Copyright of Hypnos is the property of Hypnos / Instituto Hypnos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In October and November 2014, spectra covering the 1.436 to 1.863‐μm wavelength range from the SINFONI Integral Field Unit Spectrometer on the Very Large Telescope showed the presence of a vast bright north polar cap on Uranus, extending northward from about 40°N and at all longitudes observed. The feature, first detected in August 2014 from Keck telescope images, has a morphology very similar to the southern polar cap that was seen to fade before the 2007 equinox. At strong methane‐absorbing wavelengths (for which only the high troposphere or stratosphere is sampled) the feature is not visible, indicating that it is not a stratospheric phenomenon. We show that the observed northern bright polar cap results mainly from a decrease in the tropospheric methane mixing ratio, rather than from a possible latitudinal variation of the optical properties or abundance of aerosol, implying an increase in polar downwelling near the tropopause level. [ABSTRACT FROM AUTHOR]

During Chagas disease, the Trypanosoma cruzi can induce some changes in the host cells in order to escape or manipulate the host immune response. The modulation of the lipid metabolism in the host phagocytes or in the parasite itself is one feature that has been observed. The goal of this mini review is to discuss the mechanisms that regulate intracellular lipid body (LB) biogenesis in the course of this parasite infection and their meaning to the pathophysiology of the disease. The interaction host-parasite induces LB (or lipid droplet) formation in a Toll-like receptor 2-dependent mechanism in macrophages and is enhanced by apoptotic cell uptake. Simultaneously, there is a lipid accumulation in the parasite due to the incorporation of host fatty acids. The increase in the LB accumulation during infection is correlated with an increase in the synthesis of PGE2 within the host cells and the parasite LBs. Moreover, the treatment with fatty acid synthase inhibitor C75 or non-steroidal anti-inflammatory drugs such as NS-398 and aspirin inhibited the LB biogenesis and also induced the down modulation of the eicosanoid production and the parasite replication. These findings show that LBs are organelles up modulated during the course of infection. Furthermore, the biogenesis of the LB is involved in the lipid mediator generation by both the macrophages and the parasite triggering escape mechanisms. [ABSTRACT FROM AUTHOR]

The performance of six numerical methods usually used to determine the atmospheric boundary layer (ABL) height from lidar measurements was investigated under different atmospheric conditions: results were compared with those obtained from radiosoundings to analyse their reliability for ABL-height retrievals. The selected methods were the gradient method (GM), the logarithm gradient method (LGM), the inflection point method (IPM), the wavelet covariance transform (WCT), the centroid/variance method (VM), and the cluster analysis (CA). Lidar measurements were carried out in the frame of the ‘Atmospheric Minor Species relevant to the Ozone Chemistry’ (AMISOC) project during a multi-instrument campaign conducted at the INTA/Atmospheric Observatory ‘El Arenosillo’ (INTA/ARN) in south-western Spain from 15 May to 20 June 2012. The goal of this work is to analyse the performance and robustness of the different lidar methods in this region, characterized by particular atmospheric conditions. In particular, both events of sea–land breeze regimes and episodes of Saharan dust intrusions were studied. In most days, similar results were obtained by all lidar methods in the events of sea–land breeze regimes, presenting relative absolute differences between lidar and radiosounding retrievals below 12% in average. However, big discrepancies between lidar and radiosounding retrievals are found when residual layers are present in the measurements. In such cases, the vertical extension of lidar and radiosounding profiles must to be limited to the altitude of the residual layer bottom. In a second analysis, focused on diurnal variability in the ABL heights under non-dusty (ND) and dusty (DD) conditions, the methods were tested against intensive radiosoundings launched every 4 h over 2 days. Under ND conditions, the best results were achieved for the LGM, presenting a mean of the relative absolute differences respect to radiosounding measurements of 10%. The rest of methods also provided good results with relative differences below 20% in average. Under DD conditions, however, an increase of the relative differences is found with mean values of up 32%. In this case, best results are given by CA with a mean relative difference of 20%. Despite the limited data set used in this work, results show that unlike the ND conditions for which all lidar methods provide good results respect to radiosounding retrievals, under DD conditions the election of the lidar method is a key factor for ABL estimation. However, we remark the need of extending our analysis to longer periods of time to better characterize the differences observed in this work. [ABSTRACT FROM AUTHOR]

This study deals with the ontological background reference of religious experience in general, and it aimed to demonstrate how our existential condition of finitude is imposed to understand the most varied forms of manifestations of religious phenomena that arise in the contemporary world. Thus, we will start from the distinction between a hermeneutic-phenomenological conception of the religious experience in its essence and the empirical approaches on its diverse concrete configurations. In the end, we will try to point out that the possibilities of apprehension of religious phenomena in general lack an existential element that is essentially constitutive for us, namely, the condition of the precariousness of the finite being faced with the opening of meaning that exceeds it in its horizon of transcendence. As general contribution, this way of understanding must foreclose every claim to make absolute a background meaning that should remain open as the most radical condition of possibility for the religious phenomena. [ABSTRACT FROM AUTHOR]

Three algorithms for estimating the boundary layer heights are assessed: an aerosol gradient method, a cluster analysis method, and a Haar wavelet method. Over 40 daytime clear-sky radiosonde profiles are used to compare aerosol backscatter boundary layer heights retrieved by a Vaisala CL31 ceilometer. Overall good agreement between radiosonde- and aerosol-derived boundary layer heights was found for all methods. The cluster method was found to be particularly sensitive to noise in ceilometer signals and lofted aerosol layers (48.8% of comparisons), while the gradient method showed limitations in low-aerosol-backscatter conditions. The Haar wavelet method was demonstrated to be the most robust, only showing limitations in 22.5% of all observations. Occasional differences between thermodynamically and aerosol-derived boundary layer heights were observed. [ABSTRACT FROM AUTHOR]

This study aims to indicate how the ontological difference supported by the Martin Heidegger's philosophy can serve as understanding key to a conception of the divine that, through the phenomenological dynamics directed by the dis-closure's movement of the being's truth, refuses all objectification in the last instance to preserve your sense opening. For this we will focus on divinity that accomplishes this occurrence in the most radical way: the last god. [ABSTRACT FROM AUTHOR]

Three algorithms for estimating the boundary layer heights are assessed: an aerosol gradient method, a cluster analysis method, and a Haar wavelet method. Over 40 daytime radiosonde profiles are used to compare aerosol backscatter boundary layer heights retrieved by a Vaisala CL31 ceilometer. Overall good agreement between radiosonde and aerosol derived boundary layer heights was found for all methods. The cluster method was found to be particularly sensitive to noise in ceilometer signals and lofted aerosol layers (48.8 % of comparisons), while the gradient method showed limitations in low aerosol backscatter conditions. The Haar Wavelet method demonstrating to be the most robust only showing limitations (22.5 % of all observations) due to the basic assumptions used to derive BLH from aerosol backscatter concentrations rather than errors with the algorithm itself. Disagreement between thermodynamically and aerosol derived boundary layer heights and the methodology used to estimate these heights was seen with all methods. [ABSTRACT FROM AUTHOR]

Most eukaryotic cells contain varying amounts of cytosolic lipidic inclusions termed lipid bodies (LBs) or lipid droplets (LDs). In mammalian cells, such as macrophages, these lipid-rich organelles are formed in response to host-pathogen interaction during infectious diseases and are sites for biosynthesis of arachidonic acid (AA)-derived inflammatory mediators (eicosanoids). Less clear are the functions of LBs in pathogenic lower eukaryotes. In this study, we demonstrated that LBs, visualized by light microscopy with different probes and transmission electron microscopy (TEM), are produced in trypomastigote forms of the parasite Trypanosoma cruzi, the causal agent of Chagas’ disease, after both host interaction and exogenous AA stimulation. Quantitative TEM revealed that LBs from amastigotes, the intracellular forms of the parasite, growing in vivo have increased size and electron-density compared to LBs from amastigotes living in vitro. AA-stimulated trypomastigotes released high amounts of prostaglandin E2 (PGE2) and showed PGE2 synthase expression. Raman spectroscopy demonstrated increased unsaturated lipid content and AA incorporation in stimulated parasites. Moreover, both Raman and MALDI mass spectroscopy revealed increased AA content in LBs purified from AA-stimulated parasites compared to LBs from unstimulated group. By using a specific technique for eicosanoid detection, we immunolocalized PGE2 within LBs from AA-stimulated trypomastigotes. Altogether, our findings demonstrate that LBs from the parasite Trypanosoma cruzi are not just lipid storage inclusions but dynamic organelles, able to respond to host interaction and inflammatory events and involved in the AA metabolism. Acting as sources of PGE2, a potent immunomodulatory lipid mediator that inhibits many aspects of innate and adaptive immunity, newly-formed parasite LBs may be implicated with the pathogen survival in its host. [ABSTRACT FROM AUTHOR]

Pathogens induce several changes in the host cell signaling and trafficking mechanisms in order to evade and manipulate the immune response. One prominent pathogenmediated change is the formation of lipid-rich organelles, termed lipid bodies (LBs) or lipid droplets, in the host cell cytoplasm. Protozoan parasites, which contribute expressively to the burden of infectious diseases worldwide, are able to induce LB genesis in nonimmune and immune cells, mainly macrophages, key players in the initial resistance to the infection. Under host-parasite interaction, LBs not only accumulate in the host cytoplasm but also relocate around and move into parasitophorous vacuoles. There is increasing evidence that protozoan parasites may target host-derived LBs either for gaining nutrients or for escaping the host immune response. Newly formed, parasite-induced LBs may serve as lipid sources for parasite growth and also produce inflammatory mediators that potentially act in the host immune response deactivation. In this mini review, we summarize current knowledge on the formation and role of host LBs as sites exploited by intracellular protozoan parasites as a strategy to maintain their own survival. [ABSTRACT FROM AUTHOR]

Through this essay we will attempt to question the radicalness of the opposition which the German thinker Martin Heidegger attempts to establish between what he considers as "last God" and the way he understands the God from the Jewish- Christian tradition. Thereafter we aim to indicate that the last God would answer to the need of reconfiguration of the "metaphysics' God", we will defend the point of view that this project should not necessarily implicate in the abandonment of the traditional God, but the possibility that he may be preserved in a game between distance and proximity from the last God. [ABSTRACT FROM AUTHOR]

The question of the meaning of the being will be guided here towards the affirmation of the principle of an essentially precarious condition of the mortal being, based on which the being must be radically situated in its historical and metaphysical horizon, mainly through its existential commitment to an abyssal opening of the world's phenomenon that exceeds the being's capacity of comprehension. [ABSTRACT FROM AUTHOR]

Through this essay we will attempt to question the radicalness of the opposition which the German thinker Martin Heidegger attempts to establish between what he considers as "last God" and the way he understands the God from the Jewish- Christian tradition. Thereafter we aim to indicate that the last God would answer to the need of reconfiguration of the "metaphysics' God", we will defend the point of view that this project should not necessarily implicate in the abandonment of the traditional God, but the possibility that he may be preserved in a game between distance and proximity from the last God. [ABSTRACT FROM AUTHOR]

Several procedures are widely applied to estimate the atmospheric boundary layer (ABL) top height by using aerosols as tracers from lidar measurements. These methods represent different mathematical approaches, relying on either the abrupt step of the aerosol concentration between the ABL and the free troposphere (FT) or the statistical analysis of vertical variations of the aerosol concentration. An alternative method-the cluster analysis (CA)-has been applied to lidar measurements for the first time, emerging as a useful and robust approach for calculating the ABL height, taking the advantage of both previous variables: the vertical aerosol distribution as obtained from the lidar range-corrected signal (RCS) and the statistical analysis of the RCS profiles in terms of its variance to determine a region of high aerosol loading variability. CA limitations under real situations are also tested, and the effects in ABL height determination of both noise and cloud contamination in RCS are examined. In particular, CA results are weakly sensitive to the signal noise due to the basic features of this statistical method. In addition, differences in the ABL top height, as estimated under cloudy and clear skies, have been found to be lower than 1.8% for a high RCS signal, while no effect is observed for low RCS cloud conditions. Moreover, the CA performance on the ABL top height determination for real cases is also presented, showing the reliable CA skills in reproducing the ABL evolution. [ABSTRACT FROM AUTHOR]

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By studying the evolution of the color index (CI) during twilight at high latitudes, polar stratospheric clouds (PSCs) can be detected and characterized. In this work, this method has been applied to the measurements obtained by a visible ground-based spectrometer and PSCs have been studied over the Belgrano II Antarctic station for years 2018 and 2019. The methodology applied has been validated by full spherical radiative transfer simulations, which confirm that PSCs can be detected and their altitude estimated with this instrumentation. Moreover, our investigation shows that this method is useful even in presence of optically thin tropospheric clouds or aerosols. PSCs observed in this work have been classified by altitude. Our results are in good agreement with the stratospheric temperature evolution obtained by the global meteorological model ECMWF (European Centre for Medium Range Weather Forecasts) and with satellite PSCs observations from CALIPSO (Cloud-Aerosol-Lidar and Infrared Pathfinder Satellite Observations). To investigate the presence and long-term evolution of PSCs, the methodology used in this work could also be applied to foreseen and/or historical observations obtained with ground-based spectrometers such e. g. those dedicated to Differential Optical Absorption Spectroscopy (DOAS) for trace gas observation in Arctic and Antarctic sites. [ABSTRACT FROM AUTHOR]

Images of Uranus and Neptune at different wavelengths clearly reveal the presence of hazes in their atmospheres and regions with different brightness patterns caused by latitudinal variations in the properties of aerosol. The haze formation in these planets is attributed to photochemical processes that take place in the stratosphere where methane dissociation by solar UV and energetic particles leads to a network of chemical reactions. In this work, observations performed by the SINFONI Integral Field Unit Spectrometer on the Very Large Telescope (VLT) and by the Wide Field Camera 3 (WFC3) of the Hubble Space Telescope (HST) in 2014 were analyzed with a microphysical model and a radiative transfer code to constrain the haze structure in both planets and also constrain the haze microphysics timescales. Our analyses show, for example, haze production rates in Neptune's atmosphere 10 times bigger than those found in Uranus's, or timescales for haze particles to grow and settle out to be greater than ∼ 30 years at pressure levels greater than 0.1 bar. We will discuss the implication of our results for the haze structure and formation, as well as the different factors that may control the spatial and temporal distribution of the haze over these planets. [ABSTRACT FROM AUTHOR]

Copyright of Boletin AMUP is the property of Asociacion Mexicana de Urgenciologos Pediatras A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)