Experimental comparison between R152a and R134a working in a refrigeration facility equipped with a hermetic compressor

[EN] The EU Regulation 517/2014 has recently been approved in a further attempt to curb the effects of GlobalWarming. As a consequence, the refrigeration sector is moving towards refrigerants with a low GlobalWarming Potential (GWP100) in accordance with the limit fixed by these regulations (150). In this regard, the old refrigerant R152a attracts renewed interest due to its low GWP (138) and its similarity to R134a. The present work shows the results of using R152a in a vapour compression plant equipped with a hermetic compressor and an IHX designed for R134a. The refrigerant was replaced by a conventional drop-in process in order to carry out an energy comparison. The results have revealed an improvement in the COP with R152a up to 13% despite a reduction in the cooling capacity of about 10%. During the test campaign, R134a hermetic compressors have been shown to be capable of operating with R152a.The authors acknowledge Jaume I University of Spain, who financed partially the present study through the research project P1.B2013-10.Cabello, R.; Sanchez, D.; Llopis Doménech, R.; Armendáriz Araúzo, LM.; Torrella Alcaraz, E. (2015). Experimental comparison between R152a and R134a working in a refrigeration facility equipped with a hermetic compressor. International Journal of Refrigeration. 60:92-105. https://doi.org/10.1016/j.ijrefrig.2015.06.021S921056

PDR-1/hParkin negatively regulates the phagocytosis of apoptotic cell corpses in Caenorhabditis elegans

Apoptotic cell death is an integral part of cell turnover in many tissues, and proper corpse clearance is vital to maintaining tissue homeostasis in all multicellular organisms. Even in tissues with high cellular turnover, apoptotic cells are rarely seen because of efficient clearance mechanisms in healthy individuals. In Caenorhabditis elegans, two parallel and partly redundant conserved pathways act in cell corpse engulfment. The pathway for cytoskeletal rearrangement requires the small GTPase CED-10 Rac1 acting for an efficient surround of the dead cell. The CED-10 Rac pathway is also required for the proper migration of the distal tip cells (DTCs) during the development of the C. elegans gonad. Parkin, the mammalian homolog of the C. elegans PDR-1, interacts with Rac1 in aged human brain and it is also implicated with actin dynamics and cytoskeletal rearrangements in Parkinsons's disease, suggesting that it might act on engulfment. Our genetic and biochemical studies indicate that PDR-1 inhibits apoptotic cell engulfment and DTC migration by ubiquitylating CED-10 for degradation

Increased Prevalence of Symptomatic Human Intestinal Spirochetosis in MSM with High-Risk Sexual Behavior in a Cohort of 165 Individuals

Human intestinal spirochetosis (HIS) can cause gastrointestinal symptoms, although asymptomatic infections have been described. Individuals from low-income countries, people living with HIV, and men who have sex with men (MSM) show increased risk. A retrospective review of all patients diagnosed with HIS (n = 165) between January 2013 and October 2020 at a tertiary hospital in Madrid, Spain, was performed to assess risk factors for symptomatic HIS, symptoms, and response to treatment. Most patients were male (n = 156; 94.5%), 86.7% were MSM, and 23.5% practiced chemsex, of whom most were symptomatic (p = 0.039). Most patients (78.4%) reported unprotected oral-anal intercourse. A total of 124 (81.1%) were symptomatic; diarrhea was the most common complaint (68.3%). Multivariable regression showed increased odds of symptoms associated with age under 41 (odds ratio 5.44, 95% CI 1.87-15.88; p = 0.002). Colonoscopy was normal in 153 (92.7%). Furthermore, 66.7% presented previous or concomitant sexually transmitted diseases (STDs). Among the patients, 102 underwent testing for other gastrointestinal pathogens, with positive results in 20 (19.6%). All symptomatic patients without concomitant gastrointestinal infection presenting improvement on follow-up (42 of 53) had received either metronidazole or doxycycline (p = 0.049). HIS should be considered as a cause of chronic diarrhea in MSM with high-risk sexual behavior after other causes have been ruled out; treatment with metronidazole is recommended. Coinfection with other STDs is common.S

PDR-1/hParkin negatively regulates the phagocyosis of apoptotic cell corpses in Caenorhabditis elegans

Apoptotic cell death is an integral part of cell turnover in many tissues, and proper corpse clearance is vital to maintaining tissue homeostasis in all multicellular organisms. Even in tissues with high cellular turnover, apoptotic cells are rarely seen because of efficient clearance mechanisms in healthy individuals. In Caenorhabditis elegans, two parallel and partly redundant conserved pathways act in cell corpse engulfment. The pathway for cytoskeletal rearrangement requires the small GTPase CED-10 Rac1 acting for an efficient surround of the dead cell. The CED-10 Rac pathway is also required for the proper migration of the distal tip cells (DTCs) during the development of the C. elegans gonad. Parkin, the mammalian homolog of the C. elegans PDR-1, interacts with Rac1 in aged human brain and it is also implicated with actin dynamics and cytoskeletal rearrangements in Parkinsons's disease, suggesting that it might act on engulfment. Our genetic and biochemical studies indicate that PDR-1 inhibits apoptotic cell engulfment and DTC migration by ubiquitylating CED-10 for degradation

Effects of heat waves and light deprivation on giant kelp juveniles (Macrocystis pyrifera, Laminariales, Paeophyceae

Due to climate change, the incidence of marine heat waves (MHWs) has increased, yet their effects on seaweeds are still not well understood. Adult sporophytes of Macrocystis pyrifera, the species forming the iconic giant kelp forests, can be negatively affected by thermal stress and associated environmental factors (e.g., nutrient depletion, light deprivation); however, little is known about the tolerance/vulnerability of juvenile sporophytes. Simultaneously to MHWs, juveniles can be subjected to light limitation for extended periods of time (days–weeks) due to factors causing turbidity, or even because of shading by understory canopyforming seaweeds. This study evaluated the effects of a simulated MHW (24°C, 7 d) in combination (or not) with light deprivation, on the hotosynthetic capacities, nutrient uptake, and tissue composition, as well as oxidative stress descriptors of M. pyrifera juvenile sporophytes (single blade stage, up to 20 cm length). Maximum quantum yield (Fv/Fm) decreased in juveniles under light at 24°C, likely reflecting some damage on the photosynthetic apparatus or dynamic photoinhibition; however, no other sign of physiological alteration was found in this treatment (i.e., pigments, nutrient reserves and uptake, oxidative stress). Photosynthetic capacities were maintained or even enhanced in plants under light deprivation, likely supported by photoacclimation (pigments increment); by contrast, nitrate uptake and internal storage of carbohydrates were strongly reduced, regardless of temperature. This study indicated that light limitation can be more detrimental to juvenile survival, and therefore recruitment success of M. pyrifera forests, than episodic thermal stress from MHWs.En prensa2,23

Near-IR narrow-band imaging with CIRCE at the Gran Telescopio Canarias: Searching for Lyα-emitters at z ∼ 9.3

Context. Identifying very high-redshift galaxies is crucial for understanding the formation and evolution of galaxies. However, many questions still remain, and the uncertainty on the epoch of reionization is large. In this approach, some models allow a double-reionization scenario, although the number of confirmed detections at very high z is still too low to serve as observational proof. Aims: The main goal of this project is studying whether we can search for Lyman-α emitters (LAEs) at z ∼ 9 using a narrow-band (NB) filter that was specifically designed by our team and was built for this experiment. Methods: We used the NB technique to select candidates by measuring the flux excess due to the Lyα emission. The observations were taken with an NB filter (full width at half minimum of 11 nm and central wavelength λc = 1.257 μm) and the CIRCE near-infrared camera for the Gran Telescopio Canarias. We describe a data reduction procedure that was especially optimized to minimize instrumental effects. With a total exposure time of 18.3 h, the final NB image covers an area of ∼6.7 arcmin2, which corresponds to a comoving volume of 1.1 × 103 Mpc3 at z = 9.3. Results: We pushed the source detection to its limit, which allows us to analyze an initial sample of 97 objects. We detail the different criteria we applied to select the candidates. The criteria included visual verifications in different photometric bands. None of the objects resembled a reliable LAE, however, and we found no robust candidate down to an emission-line flux of 2.9 × 10−16 erg s−1 cm−2, which corresponds to a Lyα luminosity limit of 3 × 1044 erg s−1. We derive an upper limit on the Lyα luminosity function at z ∼ 9 that agrees well with previous constraints. We conclude that deeper and wider surveys are needed to study the LAE population at the cosmic dawn

Commissioning of a synchrotron-based proton beam therapy system for use with a Monte Carlo treatment planning system

This work tackles the commissioning and validation of a novel combination of a synchrotron-based proton beam therapy system (Hitachi, Ltd.) for use with a Monte Carlo treatment planning system (TPS). Four crucial aspects in this configuration have been investigated: (1) Monte Carlo-based correction performed by the TPS to the measured integrated depth-dose curves (IDD), (2) circular spot modelling with a single Gaussian function to characterize the synchrotron physical spot, which is elliptical, (3) the modelling of the range shifter that enables using only one set of measurements in open beams, and (4) the Monte Carlo dose calculation model in small fields. Integrated depth-dose curves were measured with a PTW Bragg peak chamber and corrected, with a Monte Carlo model, to account for energy absorbed outside the detector. The elliptical spot was measured by IBA Lynx scintillator, EBT3 films and PTW microDiamond. The accuracy of the TPS (RayStation, RaySearch Laboratories) at spot modelling with a circular Gaussian function was assessed. The beam model was validated using spread-out Bragg peak (SOBP) fields. We took single-point doses at several depths through the central axis using a PTW Farmer chamber, for fields between 2 × 2cm and 30 × 30cm. We checked the range-shifter modelling from open-beam data. We tested clinical cases with film and an ioni- zation chamber array (IBA Matrix). Sigma differences for spots fitted using 2D images and 1D profiles to elliptical and circular Gaussian models were below 0.22 mm. Differences between SOBP measurements at single points and TPS calculations for all fields between 5 × 5 and 30 × 30cm were below 2.3%. Smaller fields had larger differences: up to 3.8% in the 2 × 2cm field. Mean differences at several depths along the central axis were generally below 1%. Differences in range- shifter doses were below 2.4%. Gamma test (3%, 3 mm) results for clinical cases were generally above 95% for Matrix and film. Approaches for modelling synchrotron proton beams have been validated. Dose values for open and range- shifter fields demonstrate accurate Monte Carlo correction for IDDs. Elliptical spots can be successfully modelled using a circular Gaussian, which is accurate for patient calculations and can be used for small fields. A double-Gaussian spot can improve small-field calculations. The range-shifter modelling approach, which reduces clinical commissioning time, is adequat

SIVA UAV: A Case Study for the EMC Analysis of Composite Air Vehicles

[EN] The increased use of carbon-fiber composites in unmanned aerial vehicles is a challenge for their EMC assessment by numerical solvers. For accurate and reliable simulations, numerical procedures should be tested not only for individual components, but also within the framework of complete systems. With this aim, this paper presents a benchmark test case based on experimental measurements coming from direct-current injection tests in the SIVA unmanned air vehicle, reproduced by a numerical finite-difference-time-domain solver that employs a new subgridding scheme to treat lossy composite thin panels. Validation was undertaken by applying the feature selective validation method, which quantifies the agreement between experimental and numerical data.This work was supported by the Projects TEC2013-48414C3-{ 1,2,3}-R, TEC2016-79214-C3-{1,2,3}-R, and TEC2015-68766-REDC (Spanish MINECO, EU FEDER), P12-TIC-1442 (J. de Andalucia, Spain), Alhambra-UGRFDTD (AIRBUS DS), and by the CSIRC alhambra.ugr.es supercomputing center.Cabello, MR.; Fernández, S.; Pous, M.; Pascual-Gil, E.; Angulo, LD.; López, P.; Riu, PJ.... (2017). SIVA UAV: A Case Study for the EMC Analysis of Composite Air Vehicles. IEEE Transactions on Electromagnetic Compatibility. 59(4):1103-1113. https://doi.org/10.1109/TEMC.2017.2648507S1103111359

10 Myr evolution of sedimentation rates in a deep marine to non-marine foreland basin system: Tectonic and sedimentary controls (Eocene, Tremp–Jaca Basin, Southern Pyrenees, NE Spain)

The propagation of the deformation front in foreland systems is typically accompanied by the incorporation of parts of the basin into wedge-top piggy-back basins, this process is likely producing considerable changes to sedimentation rates (SR). Here we investigate the spatial-temporal evolution of SR for the Tremp–Jaca Basin in the Southern Pyrenees during its evolution from a wedge-top, foreredeep, forebulge configuration to a wedge-top stage. SR were controlled by a series of tectonic structures that influenced subsidence distribution and modified the sediment dispersal patterns. We compare the decompacted SR calculated from 12 magnetostratigraphic sections located throughout the Tremp–Jaca Basin represent the full range of depositional environment and times. While the derived long-term SR range between 9.0 and 84.5 cm/kyr, compiled data at the scale of magnetozones (0.1–2.5 Myr) yield SR that range from 3.0 to 170 cm/kyr. From this analysis, three main types of depocenter are recognized: a regional depocenter in the foredeep depozone; depocenters related to both regional subsidence and salt tectonics in the wedge-top depozone; and a depocenter related to clastic shelf building showing transgressive and regressive trends with graded and non-graded episodes. From the evolution of SR we distinguish two stages. The Lutetian Stage (from 49.1–41.2 Ma) portrays a compartmentalized basin characterized by variable SR in dominantly underfilled accommodation areas. The markedly different advance of the deformation front between the Central and Western Pyrenees resulted in a complex distribution of the foreland depozones during this stage. The Bartonian–Priabonian Stage (41.2–36.9 Ma) represents the integration of the whole basin into the wedge-top, showing a generalized reduction of SR in a mostly overfilled relatively uniform basin. The stacking of basement units in the hinterland during the whole period produced unusually high SR in the wedge-top depozoneAgència de Gestió d'Ajuts Universitaris i de Recerca, Grant/Award Number: 2017SGR596; Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: BES-2015-073302 and CGL2014-55900-P; Swiss National Science Foundation, Grant/Award Number: 200020_18201