Spin evolution of Earth-sized exoplanets, including atmospheric tides and core-mantle friction

Planets with masses between 0.1 and 10M(circle plus) are believed to host dense atmospheres. These atmospheres can play an important role on the planet's spin evolution, since thermal atmospheric tides, driven by the host star, may counterbalance gravitational tides. In this work, we study the long-term spin evolution of Earth-sized exoplanets. We generalize previous works by including the effect of eccentric orbits and obliquity. We show that under the effect of tides and core-mantle friction, the obliquity of the planets evolves either to 0 degrees or 180 degrees. The rotation of these planets is also expected to evolve into a very restricted number of equilibrium configurations. In general, none of these equilibria is synchronous with the orbital mean motion. The role of thermal atmospheric tides becomes more important for Earth-sized planets in the habitable zones of their systems; so they cannot be neglected when we search for their potential habitability

Mercury's capture into the 3/2 spin-orbit resonance including the effect of core-mantle friction

The rotation of Mercury is presently captured in a 3/2 spin-orbit resonance with the orbital mean motion. The capture mechanism is well understood as the result of tidal interactions with the Sun combined with planetary perturbations. However, it is now almost certain that Mercury has a liquid core, which should induce a contribution of viscous friction at the core-mantle boundary to the spin evolution. This last effect greatly increases the chances of capture in all spin-orbit resonances, being 100% for the 2/1 resonance, and thus preventing the planet from evolving to the presently observed configuration. Here we show that for a given resonance, as the chaotic evolution of Mercury's orbit can drive its eccentricity to very low values during the planet's history, any previous capture can be destabilized whenever the eccentricity becomes lower than a critical value. In our numerical integrations of 1000 orbits of Mercury over 4 Gyr, the spin ends 99.8% of the time captured in a spin-orbit resonance, in particular in one of the following three configurations: 5/2 (22%), 2/1 (32%) and 3/2 (26%). Although the present 3/2 spin-orbit resonance is not the most probable outcome, we also show that the capture probability in this resonance can be increased up to 55% or 73%, if the eccentricity of Mercury in the past has descended below the critical values 0.025 or 0.005, respectively.Comment: 14 pages, 7 figure

Heterotic String Compactifications on Half-flat Manifolds II

In this paper, we continue the analysis of heterotic string compactifications on half-flat mirror manifolds by including the 10-dimensional gauge fields. It is argued, that the heterotic Bianchi identity is solved by a variant of the standard embedding. Then, the resulting gauge group in four dimensions is still E6 despite the fact that the Levi-Civita connection has SO(6) holonomy. We derive the associated four-dimensional effective theories including matter field terms for such compactifications. The results are also extended to more general manifolds with SU(3) structure.Comment: 31 page

Different proportion of root cutting and shoot pruning influence the growth of citronella plants

Environment concern, sustainable products demand, and natural components conscious are currently global movement factors. Related to the global movement factors, citronella grass (Cymbopogon nardus L.) is being widely used in folk medicine, and has insect repellent activity, fungal and bactericidal action. Its essential oil has high content of citronellal, citronellol, geraniol. The essential oil is mostly extracted from leaves which turns this plant with high commercial demand. However, to obtain the best therapeutic quality and productivity of medicinal plants, which culminates in greater quantity and quality of the active compounds, the proper management of the crop is fundamental, as several factors can interfere during its growth and development. Thus, we analyzed the growth of citronella plants submitted to different levels of shoot and root cuts. Five different proportions of root pruning (0, 25, 50, 75, 100%), after 145 days of seedling planting and four cuttings in the shoots: blunt; a cut at 145 DAP (days after planting) along with the root cut; a cut at 228 DAP; and cuts at 145 and 228 DAP (two cuts). Four harvesting for dry matter accumulation and photoassimilate partition data were performed. The treatment with 100% root cut, but without leaf cut, increased the total dry mass accumulation of the plant in relation to the other treatments, for the last analysis period, demonstrating a recovery. Thus, the application of two leaf cuts or no leaf cutting within the 100% root cut treatment for leaf dry mass accumulation is more effective when compared to the blunt root treatment

Effect of plant biostimulants on nutritional and chemical profiles of almond and hazelnut

The increasing interest in natural foods with functional effects demands progressively higher production levels. Nonetheless, there is an orientation towards practicing more sustainable agriculture, free from environmentally harmful pesticides and fertilizers. Plant biostimulants, a class of bio-based agriculture products designed to improve crop development, represent a feasible alternative to chemical fertilizers, or, at least, an effective way of reducing the employed quantities. Herein, different types of plant biostimulants compatible with organic farming (Phytoalgae, Foliar B, Amino Acids, Soil B, Fitoalgas Green® and Sprint Plus®) were tested in two of the most important nut products worldwide: almonds and hazelnuts, which were tested for nutritional parameters, fatty acids profiles and tocopherols contents. Overall, the most notorious effects in almond samples were obtained with phytoalgae (seaweed Ascophyllum nodosum extracts), particularly reflected in the upraising around 10% of -tocopherol and -tocopherol contents. Likewise, hazelnuts treated with NPK + phytoalgae were also characterized by an increase of almost 18% in tocopherols levels, while treatment with NPK alone induced 15.1% higher percentage of linoleic acid.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); to the national funding by FCT, P.I., through the institutional scientific employment program-contract for L. Barros and individual scientific employment program-contract (CEECIND/04479/2017). Further acknowledgments are due to the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte-01-0247- FEDER-024479: ValorNatural®, whom the author F.S. Reis thanks for her contract. This work was also funded by FEDER-Interreg España-Portugal programme through the project TRANSCo- LAB 0612_TRANS_CO_LAB_2_P, and integrated in the activities of the Operational Group EGIS– Estratégias de Gestão Integrada do Solo e da Água em Espécies Produtoras de Frutos Secos, funded by PT2020 and EAFRD (European Agricultural Fund for Rural Development).info:eu-repo/semantics/publishedVersio

A new methodology for assessment of pectus excavatum correction after bar removal in Nuss procedure: preliminary study

Purpose: The objective is to present a new methodology to assess quantitatively the impact of bar removal on the anterior chest wall, among patients with pectus excavatum who have undergone the Nuss procedure, and present a preliminary study using this methodology. Methods: We propose to acquire, for each patient, the surface of the anterior chest wall using a three-dimensional laser scanner at subsequent time points (short term: before and after surgery; long term: follow-up visit, 6 months, and 12 months after surgery). After surfaces postprocessing, the changes are assessed by overlapping and measuring the distances between surfaces. In this preliminary study, three time points were acquired and two assessments were performed: before vs after bar removal (early) and before vs 2-8 weeks after bar removal (interim). In 21 patients, the signed distances and volumes between surfaces were computed and the data analysis was performed. Results: This methodology revealed useful for monitoring changes in the anterior chest wall. On average, the mean, maximum, and volume variations, in the early assessment, were -0.1 +/- 0.1 cm, -0.6 +/- 0.2 cm, and 47.8 +/- 22.2 cm(3), respectively; and, in the interim assessment, were -0.5 +/- 0.2 cm, -1.3 +/- 0.4 cm, and 122.1 +/- 47.3 cm3, respectively (p < 0.05). Data analysis revealed that the time the bar was in situ was inversely and significantly correlated with postretraction and was a relevant predictor of its decrease following surgery (p < 0.05). Additionally, gender and age suggested influencing the outcome. Conclusions: This methodology is novel, objective and safe, helping on follow-up of pectus excavatum patients. Moreover, the preliminary study suggests that the time the bar was in situ may be the main determinant of the anterior chest wall retraction following bar removal. Further studies should continue to corroborate and reinforce the preliminary findings, by increasing the sample size and performing long-term assessments.FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the projects PTDC/SAU-BEB/103368/2008 and POCI-01-0145-FEDER-007038; and by the projects NORTE-07-0124-FEDER-000017 and NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER)info:eu-repo/semantics/publishedVersio

Ionic and conformational mobility in poly(vinylidene fluoride)/ionic liquid blends: Dielectric and electrical conductivity behavior

[EN] The glass transition dynamics and the charge transport for blends composed of poly(vinylidene fluoride) (PVDF) and the ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide, [Emim] [TESI] have been investigated as a function of different IL content (0, 10, 25 and 40 % wt) by differential scanning calorimetry (DSC), dynamic-mechanical analysis (DMA) and broadband dielectric relaxation spectroscopy (BDS) in wide frequency and temperature ranges (0.1 Hz-1 MHz and -120 to 150 degrees C, respectively). The inclusion of the IL in the polymer matrix affected the main relaxation process (beta-relaxation) of the amorphous phase of the polymer matrix detected with all the techniques employed. It is demonstrated, that the chain segments of PVDF and the IL are mixed at the nanometer range. The blends were homogeneous regardless of the amount of IL and the glass transition temperature (Tg) shifted to lower temperatures as the IL content was increased. A good agreement between the Tg measured by BDS and DSC was observed for all PVDF/IL samples. The conductivity formalism revealed significant contributions of the IL concentration to the conductivity behavior of the blends in that is described by charge motion and electrode polarization effects. The activation energy of all the PVDF/IL samples, calculated by Dyre model, decreased with IL addition with respect to that of neat PVDF. (C) 2018 Elsevier Ltd. All rights reserved.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. The authors thank FEDER funds through the COMPETE 2020 Programme and National Funds through FCT under the projects PTDC/CTM-ENE/5387/2014, PTDC/EEI-SII/5582/2014 and UID/CTM/50025/2013 and Grants SFRH/BPD/121526/2016 (D.M.C.), SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including the FEDER financial support) and from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. CIBER Actions are financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Correia, D.; Sabater I Serra, R.; Gómez-Tejedor, JA.; De Zea Bermudez, V.; Andrio Balado, A.; Meseguer Dueñas, JM.; Gómez Ribelles, JL.... (2018). Ionic and conformational mobility in poly(vinylidene fluoride)/ionic liquid blends: Dielectric and electrical conductivity behavior. Polymer. 143:164-172. https://doi.org/10.1016/j.polymer.2018.04.019S16417214

Study on COgnition and Prognosis in the Elderly (SCOPE): baseline characteristics

Blood Press. 2000;9(2-3):146-51. Study on COgnition and Prognosis in the Elderly (SCOPE): baseline characteristics. Hansson L, Lithell H, Skoog I, Baro F, Bánki CM, Breteler M, Castaigne A, Correia M, Degaute JP, Elmfeldt D, Engedal K, Farsang C, Ferro J, Hachinski V, Hofman A, James OF, Krisin E, Leeman M, de Leeuw PW, Leys D, Lobo A, Nordby G, Olofsson B, Opolski G, Prince M, Reischies FM. University of Uppsala, Department of Public Health, Clinical Hypertension Research, Sweden. Abstract The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multi-centre, prospective, randomized, double-blind, parallel-group study. The primary objective of SCOPE is to assess the effect of the angiotensin II type 1 (AT1) receptor blocker, candesartan cilexetil 8-16 mg once daily, on major cardiovascular events in elderly patients (70-89 years of age) with mild hypertension (DBP 90-99 and/or SBP 160-179 mmHg). The secondary objectives of the study are to test the hypothesis that antihypertensive therapy can prevent cognitive decline (as measured by the Mini Mental State Examination, MMSE) and dementia, and to assess the effect of therapy on total mortality, myocardial infarction (MI), stroke, renal function, and hospitalization. A total of 4964 patients from 15 participating countries were recruited during the randomization phase of SCOPE, exceeding the target population of 4000. The mean age of the patients at enrolment was 76 years, the ratio of male to female patients was approximately 1:2, and 52% of patients were already being treated with an antihypertensive agent at enrolment. The majority of patients (88%) were educated to at least primary school level. At randomization, mean sitting blood pressure values were SBP 166 mmHg and DBP 90 mmHg, and the mean MMSE score was 28. Previous cardiovascular disease in the study population included myocardial infarction (4%), stroke (4%) and atrial fibrillation (4%). Men, more often than women, had a history of previous MI, stroke and atrial fibrillation. A greater percentage of men were smokers (13% vs 6% in women) and had attended university (11% vs 3% of women). Of the randomized patients, 21% were 80 years of age. In this age group smoking was less common (4% vs 10% for 70-79-year-olds) and fewer had attended university (4% vs 7% for 70-79-year-olds). The incidence of MI was similar in both age groups. However, stroke and atrial fibrillation had occurred approximately twice as frequently in the older patients. The patients' mean age at baseline was similar in the participating countries, and most countries showed the approximate 1:2 ratio for male to female patients. There was also little inter-country variation in terms of mean SBP, DBP or MMSE score. However, there was considerable regional variation in the percentage of patients on therapy prior to enrolment. PMID: 10855739 [PubMed - indexed for MEDLINE

Study on COgnition and Prognosis in the Elderly (SCOPE)

Blood Press. 1999;8(3):177-83. Study on COgnition and Prognosis in the Elderly (SCOPE). Hansson L, Lithell H, Skoog I, Baro F, Bánki CM, Breteler M, Carbonin PU, Castaigne A, Correia M, Degaute JP, Elmfeldt D, Engedal K, Farsang C, Ferro J, Hachinski V, Hofman A, James OF, Krisin E, Leeman M, de Leeuw PW, Leys D, Lobo A, Nordby G, Olofsson B, Zanchetti A, et al. University of Uppsala, Department of Public Health, Sweden. Abstract The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multicentre, prospective, randomized, double-blind, parallel-group study designed to compare the effects of candesartan cilexetil and placebo in elderly patients with mild hypertension. The primary objective of the study is to assess the effect of candesartan cilexetil on major cardiovascular events. The secondary objectives of the study are to assess the effect of candesartan cilexetil on cognitive function and on total mortality, cardiovascular mortality, myocardial infarction, stroke, renal function, hospitalization, quality of life and health economics. Male and female patients aged between 70 and 89 years, with a sitting systolic blood pressure (SBP) of 160-179 mmHg and/or diastolic blood pressure (DBP) of 90-99 mmHg, and a Mini-Mental State Examination (MMSE) score of 24 or above, are eligible for the study. The overall target study population is 4000 patients, at least 1000 of whom are also to be assessed for quality of life and health economics data. After an open run-in period lasting 1-3 months, during which patients are assessed for eligibility and those who are already on antihypertensive therapy at enrolment are switched to hydrochlorothiazide 12.5 mg o.d., patients are randomized to receive either candesartan cilexetil 8 mg once daily (o.d.) or matching placebo o.d. At subsequent study visits, if SBP remains >160 mmHg, or has decreased by 85 mmHg, study treatment is doubled to candesartan cilexetil 16 mg o.d. or two placebo tablets o.d. Recruitment was completed in January 1999. At that time 4964 patients had been randomized. All randomized patients will be followed for an additional 2 years. If the event rate is lower than anticipated, the follow-up will be prolonged. PMID: 10595696 [PubMed - indexed for MEDLINE