Study of Some Planetary Atmospheres Features by Probe Entry and Descent Simulations

Characterization of planetary atmospheres is analyzed by its effects in the entry and descent trajectories of probes. Emphasis is on the most important variables that characterize atmospheres e.g. density profile with altitude. Probe trajectories are numerically determined with ENTRAP, a developing multi-purpose computational tool for entry and descent trajectory simulations capable of taking into account many features and perturbations. Real data from Mars Pathfinder mission is used. The goal is to be able to determine more accurately the atmosphere structure by observing real trajectories and what changes are to expect in probe descent trajectories if atmospheres have different properties than the ones assumed initially

General dissipation coefficient in low-temperature warm inflation

In generic particle physics models, the inflaton field is coupled to other bosonic and fermionic fields that acquire large masses during inflation and may decay into light degrees of freedom. This leads to dissipative effects that modify the inflationary dynamics and may generate a nearly-thermal radiation bath, such that inflation occurs in a warm rather than supercooled environment. In this work, we perform a numerical computation and obtain expressions for the associated dissipation coefficient in supersymmetric models, focusing on the regime where the radiation temperature is below the heavy mass threshold. The dissipation coefficient receives contributions from the decay of both on-shell and off-shell degrees of freedom, which are dominant for small and large couplings, respectively, taking into account the light field multiplicities. In particular, we find that the contribution from on-shell decays, although Boltzmann-suppressed, can be much larger than that of virtual modes, which is bounded by the validity of a perturbative analysis. This result opens up new possibilities for realizations of warm inflation in supersymmetric field theories.Comment: 25 pages, 13 figures; revised version with new results added; published in JCA

Warming up for Planck

The recent Planck results and future releases on the horizon present a key opportunity to address a fundamental question in inflationary cosmology of whether primordial density perturbations have a quantum or thermal origin, i.e. whether particle production may have significant effects during inflation. Warm inflation provides a natural arena to address this issue, with interactions between the scalar inflaton and other degrees of freedom leading to dissipative entropy production and associated thermal fluctuations. In this context, we present relations between CMB observables that can be directly tested against observational data. In particular, we show that the presence of a thermal bath warmer than the Hubble scale during inflation decreases the tensor-to-scalar ratio with respect to the conventional prediction in supercooled inflation, yielding $r< 8|n_t|$, where $n_t$ is the tensor spectral index. Focusing on supersymmetric models at low temperatures, we determine consistency relations between the observables characterizing the spectrum of adiabatic scalar and tensor modes, both for generic potentials and particular canonical examples, and which we compare with the WMAP and Planck results. Finally, we include the possibility of producing the observed baryon asymmetry during inflation through dissipative effects, thereby generating baryon isocurvature modes that can be easily accommodated by the Planck data.Comment: 14 pages, 10 figures. Published in JCA

Extinction law variations and dust excitation in the spiral galaxy NGC 300

We investigate the origin of the strong radial gradient in the ultraviolet-to-infrared ratio in the spiral galaxy NGC 300, and emphasize the importance of local variations in the interstellar medium geometry, concluding that they cannot be neglected with respect to metallicity effects. This analysis is based upon a combination of maps from GALEX and Spitzer, and from the ground (UBVRI, Halpha and Hbeta). We select ionizing stellar clusters associated with HII regions of widely varying morphologies, and derive their fundamental parameters from population synthesis fitting of their spectral energy distributions, measured to eliminate local backgrounds accurately. From these fits, we conclude that the stellar extinction law is highly variable in the line of sight of young clusters of similar ages. In the particular model geometry that we consider most appropriate to the sampled regions, we checked that our findings are not significantly altered by the correct treatment of radiative transfer effects. The variations are systematic in nature: extinction laws of the Milky Way or LMC type are associated with compact HII regions (the compacity being quantified in two different ways), while clusters surrounded by diffuse HII regions follow extinction laws of the 30 Doradus or SMC type. The Calzetti starburst attenuation law, although most often degenerate with the 30 Doradus extinction law, overpredicts ionizing photon fluxes by large amounts. We also find that the extinction law variations are correlated with the column density of dust species emitting in the near- and mid-infrared. Finally, we briefly discuss the nebular to stellar extinction ratios, and the excitation of aromatic band carriers, invalidating their claimed association with cold dust.Comment: accepted for publication in ApJ -- figure 6 abridged her

Multiplexed immunosensors for point-of-care diagnostic applications

Accurate, reliable, and cost-effective immunosensors are clinically important for the early diagnosis and monitoring of progressive diseases, and multiplexed sensing is a promising strategy for the next generation of diagnostics. This strategy allows for the simultaneous detection and quantification of multiple biomarkers with significantly enhanced reproducibility and reliability, whilst requiring smaller sample volumes, fewer materials, and shorter average analysis time for individual biomarkers than individual tests. In this opinionated review, we compare different techniques for the development of multiplexed immunosensors. We review the state-of-the-art approaches in the field of multiplexed immunosensors using electrical, electrochemical, and optical methods. The barriers that prevent translating this sensing strategy into clinics are outlined together with the potential solutions. We also share our vision on how multiplexed immunosensors will continue their evolution in the coming years

A systematic review and meta-analysis of randomized controlled trials

Funding Information: This work was conducted at the Interdisciplinary Center for the Study of Human Performance (CIPER), unit I&D 447 (UIDB/00447/2020), Faculty of Human Kinetics of the University of Lisbon, and supported by the Portuguese Foundation for Science and Technology , the Portuguese Ministry of Science. IRC and GBR are supported by the Portuguese Foundation for Science and Technology ( IRC: SFRH/BD/149394/2019 ; GBR: 2020.07856.BD ). Publisher Copyright: © 2023 The AuthorsObjectives: This systematic review and meta-analysis aimed to investigate the effects of home-based exercise on physical fitness (cardiorespiratory fitness, muscle strength, and body composition) in cancer patients undergoing active treatment. Design: Systematic review with meta-analysis and Grading Recommendations Assessment, Development, and Evaluation of the evidence. Methods: A comprehensive search of existing literature was carried out in four electronic databases: PubMed, Web of Science, Scopus, and PEDro. All databases were searched for randomized controlled trials assessing the effects of home-based exercise on physical fitness outcomes in cancer patients during active treatment. Multicomponent interventions (i.e., exercise plus diet/behavioral therapy) were excluded. The methodological quality of each study was assessed using the Revised Cochrane risk-of-bias tool for randomized trials. Meta-analytical procedures were performed when appropriate and standardized mean differences (SMD) were calculated. Results: Twenty-eight randomized controlled trials (n = 2424 cancer patients) were included. Most of the interventions were conducted in breast cancer patients (n = 13) during the adjuvant treatment period (n = 17); 18 studies included a walking component in their home-based protocol. Home-based exercise was effective at improving the distance of the 6-minute walk test (k = 6; SMD = 0.321, p = 0.010). However, the results were no longer significant when performing sensitivity analysis based on exclusively walking (k = 1) and non-exclusively walking interventions (k = 5; SMD = 0.258; p = 0.072). No effects were found for muscle strength and body composition outcomes (p > 0.05). Conclusions: Regular home-based exercise programs are an effective strategy to improve 6-minutes walk test in cancer patients undergoing active treatment. Conversely, no alterations were found in muscle strength and body composition.proofepub_ahead_of_prin

Warm Little Inflaton becomes Dark Energy

We present a model where the inflaton field behaves like quintessence at late times, generating the present phase of accelerated expansion. This is achieved within the framework of warm inflation, in particular the Warm Little Inflaton scenario, where the underlying symmetries guarantee a successful inflationary period in a warm regime sustained by dissipative effects without significant backreaction on the scalar potential. This yields a smooth transition into a radiation-dominated epoch, at which point dissipative effects naturally shut down as the temperature drops below the mass of the fermions directly coupled to the inflaton. The post-inflationary dynamics is then analogous to a thawing quintessence scenario, with no kination phase at the end of inflation. Observational signatures of this scenario include the modified consistency relation between the tensor-to-scalar ratio and tensor spectral index typical of warm inflation models, the variation of the dark energy equation of state at low redshifts characteristic of thawing quintessence scenarios, and correlated dark energy isocurvature perturbations.publishe

Physical activity moderates the effect of sedentary time on an older adult's physical independence

Background/objectives: Moderate-to-vigorous physical activity (MVPA) and breaks in sedentary time (BST) have been proposed as viable solutions to improve an older adult's physical independence, whereas sedentary time (ST) has been associated with detrimental effects. We sought to assess the joint effects of ST, BST, and MVPA on the physical independence of older adults and determine whether and to what extent the ST relationship with physical independence is moderated by MVPA and/or BST. Design: Cross-sectional. Setting: Laboratory of Exercise and Health, Faculty of Human Kinetics. Participants: Older adults (≥65 years old) from the national surveillance sys tem in Portugal (n = 821). Measurements: Physical activity and ST were assessed by accelerometry. Physi cal independence was assessed using a 12-item composite physical function (CPF) questionnaire. Multiple linear regression was used to model the outcomes. Results: Higher ST was related to lower CPF score (β = −0.01, p < 0.0001), whereas higher MVPA was related to better CPF score (β = 0.02, p < 0.0001). BST was not related to physical independence after accounting for MVPA and ST (β = 0.03, p = 0.074). MVPA had a moderating effect on the relationship of ST with CPF score (p < 0.0001), where MVPA ≥36.30 min/day ameliorated the significant inverse relationship between ST and CPF. Engaging in ≥107.78 of MVPA resulted in ST having a significant positive relationship with CPF score. No moderation effect was found for BST (p > 0.05). Conclusion: Regardless of the time spent in MVPA and BST, ST was inversely related to CPF. However, MVPA was found to be a moderator of the relationship between ST and physical independence, such that engaging in at least 36 min/day of MVPA may blunt the negative effects of ST. At high levels of MVPA (≥108 min/day), having some ST may actually provide some benefit to an older adult's ability to maintain physical independence

Comparative validation of three contemporary bleeding risk scores in acute coronary syndromes

Background: Hemorrhagic complications are strongly linked with subsequent adverse outcomes in acute coronary syndrome (ACS) patients. Various risk scores (RS) are available to estimate the bleeding risk in these patients. Aims: To compare the predictive accuracy of the three contemporary bleeding RS in ACS. Methods: We studied 4500 consecutive patients with ACS. For each patient, the ACTION, CRUSADE, and Mehran et al bleeding RS were calculated. We assessed their performance either for the prediction of their own major bleeding events or to predict the TIMI serious (major and minor) bleeding episodes in the overall population, in patients with non-ST elevation ACS (NSTEACS) and in those with ST-elevation myocardial infarction (STEMI) patients. Calibration (Hosmer-Lemeshow test) and discrimination (c-statistic) for the three RS were computed and compared. We used the concept of net reclassification improvement (NRI) to compare the incremental prognostic value of using a particular RS over the remaining scores in predicting the TIMI serious bleeding. Results: The best predictive accuracy was obtained by the CRUSADE score either for the prediction of its own major bleeding events (c-statistic=0.80, 0.791, and 0.81 for the entire sample, for STEMI, and for NSTEACS patients, respectively) or to predict the TIMI serious bleed occurrence (c-statistic=0.741, 0.738,and 0.745 for the whole population, for STEMI and NSTEACS patients, respectively). The lowest bleeding rates observed in patients classified as low risk corresponded to the CRUSADE RS. All scores performed modestly in patients who did not undergo coronariography (all c-statistic <0.70). The CRUSADE score was significantly superior to the ACTION model in predicting the TIMI serious bleeding occurrence in terms of NRI overall and by ACS subgroups (p<0.05). Overall, the CRUSADE RS exhibited better calibration for predicting the TIMI serious bleeding compared to the ACTION and Mehran et al scores (Hosmer-Lemeshow p-values of 0.26, 0.13, and 0.07, respectively). Conclusion: The CRUSADE score represents, among the more contemporary bleeding RS, the most accurate and reliable quantitative clinical tool in STEACS and STEMI patients. We encourage the utilization of the CRUSADE index for bleeding risk stratification purposes in daily clinical practice and in ACS outcome studies. The performance of the three more contemporary bleeding RS is modest in those patients who received conservative management