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Lignocellulosic wastes from Amazonian crops are promising for the production of biochar. However, there are scientific gaps concerning the thermodegradation mechanisms of widely diverse biomass. This research explored the relationships between the chemical compounds and the pyrolysis behavior of the acai seed, cocoa pod husk, coconut husk, palm empty fruit bunch, and maize cob by thermogravimetric analysis. The cocoa pod husk and palm empty fruit bunch showed the lowest temperatures of initial degradation (≤ 230 °C) because of the highest proportions of total extractives (≥ 17% dry basis) and ashes (≥ 5.7% dry basis) combined with the lowest contents of holocellulose (≤ 56% dry basis). Biomasses with higher extractives contents showed pronounced mass losses at temperatures ≤ 300 °C. The maize cob, with more holocellulose (68% dry basis), revealed a high maximum rate of thermal degradation of 7.9% min−1 and mass loss between 200 and 400 °C of 65.6% wet basis. The high level of acetone-soluble extractives raised the temperature necessary for the initial thermal degradation of acai seed. The coconut husk, acai seed, and cocoa pod husk were the most suitable wastes for the production of biochar based on the average mass yields (≥ 41% wet basis) at the pyrolysis final temperature of 400 °C.

Several studies on the pathophysiological and epidemiological characteristics of SARS-CoV-2 indicate the extracorporeal viability of the virus and the possibility of faecal-oral transmission through contaminated natural water and wastewater, suggesting a potential risk of spreading in socially vulnerable areas, such as the Brazilian Amazon, where access to sanitation and health services is lacking. Thus, an attempt we made to outline an overview of sanitation in the Brazilian Amazon and its possible impacts on the most vulnerable populations and on the health system in a pandemic situation, based on bibliographic and documentary review and exploratory analysis of data related to basic sanitation and health. The Amazon has a huge deficit in sanitation and in the structure of health services, especially in rural areas, increasing the risk of spreading infectious diseases such as COVID-19, whose progress has placed some of the Amazonian states in a prominent position in the rankings of incidence and mortality. What do you want to do ? New mail Copy

We present a study of the evolutionary state of a few lithium-rich giant stars based on the Gaia Data Release 2 (DR2) parallaxes and photometry. We also investigate the chromospheric activity, the presence of a surface magnetic field, and the radial velocity for our sample stars. We analysed both archive and new data. We gathered archive spectra from several instruments, mainly ELODIE and NARVAL, and we added new data acquired with the spectrograph MUSICOS. We applied the least-squares deconvolution technique to obtain Stokes V and I mean profiles to compute longitudinal magnetic field for a subset. Moreover, for the same subset, we analysed the Ca ii H&K emission lines to calculate the S-index. We also derived atmospheric parameters and Li abundances for all 18 stars of our sample. We found that stars previously classified as red giant branch (RGB) may actually be at a different evolutionary state. Furthermore, we identified that most stars in our sample with detection of surface magnetic field show at least moderate rotation velocities, but none the less, we could not detect a magnetic field in two fast rotators. Because of our small sample of magnetic giants, it is difficult to determine if the presence of surface magnetic field and the Li-rich giant phenomena could be somehow linked. The large variation of the radial velocity of part of our sample indicates that some of them might have a binary companion, which may change the way we look at the Li problem in giant stars.

Solar analogues are important stars to study for understanding the properties of the Sun. Evolutionary modeling, combined with seismic and spectroscopic analysis, becomes a powerful method to characterize stellar intrinsic parameters, such as mass, radius, metallicity and age.However, these characteristics, relevant for other aspects of astrophysics or exoplanetary system physics for example, are difficult to obtain with a high precision and/or accuracy. The goal of this study is to characterize the two solar analogues HD42618 and HD43587, observed by CoRoT. In particular, we aim to infer precise mass, radius, and age, using evolutionary modeling constrained by spectroscopic, photometric, and seismic analysis. These stars show evidences of being older than the Sun but with a relatively large lithium abundance. We present the seismic analysis of HD42618, and the modeling of the two solar analogs HD42618 andHD43587 using the CESTAM stellar evolution code. Models were computed to reproduce the spectroscopic (effective temperature and metallicity) and seismic (mode frequencies) data,and the luminosity of the stars, based on Gaia parallaxes. We infer very similar values of mass and radius for both stars compared to the literature, within the uncertainties, and reproduce correctly the seismic constraints. For HD42618, the modeling shows it is slightly less massive and older than the Sun. For HD43587, it confirms it is more massive and older than the Sun,in agreement with previous results. The use of chemical clocks improves the reliability of our age estimates., 8 pages, 5 figures, 4 tables

A major obstacle to interpreting the rotation period distribution for main-sequence stars from Kepler mission data has been the lack of precise evolutionary status for these objects. We address this by investigating the evolutionary status based on Gaia Data Release 2 parallaxes and photometry for more than 30,000 Kepler stars with rotation period measurements. Many of these are subgiants, and should be excluded in future work on dwarfs. We particularly investigate a 193-star sample of solar analogs, and report newly-determined rotation periods for 125 of these. These include 54 stars from a prior sample, of which can confirm the periods for 50. The remainder are new, and 10 of them longer than solar rotation period, suggesting that sun-like stars continue to spin down on the main sequence past solar age. Our sample of solar analogs could potentially serve as a benchmark for future missions such as PLATO, and emphasizes the need for additional astrometric, photometric, and spectroscopic information before interpreting the stellar populations and results from time-series surveys., Comment: 10 pages, 8 Figures, 2 tables. accepted to be published on The Astrophysical Journal (June 8, 2020)

It is well established that there is a breakdown in the curve of specific angular momentum as a function of mass for stars on the main sequence Ref. 5. Stars earlier than F5 and more massive than the sun, rotate rapidly over a large mass range. For spectral type F5 and later, including the Sun, much smaller rotational velocities are found. We revisit this question from a new sample to shed a light on the basis of a sample solar twins and analogs recently observed by interferometric measurements of stellar radius. Our results clearly show that, as the Sun, the solar twins present similar global behavior from their specific angular momentum. 18 Sco and HIP 100963 have a specific angular momentum one order higher than the solar value, and HIP 55459 and HIP 56948 have a specific angular momentum one order lower than the solar value.

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A new sample of solar analogs and twin candidates have been constructed and studied, with particular attention to their light curves from NASA's Kepler mission. This letter aims to assess the evolutionary status, derive their rotation and ages and identify those solar analogs or solar twin candidates. We separate out the subgiants that compose a large fraction of the asteroseismic sample, and which show an increase in the average rotation period as the stars ascend the subgiant branch. The rotation periods of the dwarfs, ranging from 6 to 30 days, and averaged 19d, allow us to assess their individual evolutionary states on the main sequence, and to derive their ages using gyrochronology. These ages are found to be in agreement with a correlation coefficient of r = 0.79 with the independent asteroseismic ages, where available. As a result of this investigation, we are able to identify 34 stars as solar analogs and 22 of them as solar twin candidates., Comment: Accepted to publication on the Astrophysical Journal Letters (ApJL). 5 pages, 4 figures and 1 Table. Manuscript LET31659R1. Press release: http://www.cfa.harvard.edu/news/

In 1995, cervical cancer was the fourth most important cause of death among women in the state of Rio Grande do Sul, Brazil. There are no available studies on Pap smear examination coverage in Pelotas, which is the largest city in the southern part of Rio Grande do Sul. Accordingly, in 1992 a population-based, cross-sectional study was carried out among 20 to 69 year-old women residing in urban areas of the city. The objectives of the study were to ascertain any Pap smear testing in the 3 years prior to the study, to determine the coverage of cervical cancer screening, and to identify any factors associated with the performance of Pap tests in Pelotas. Social class was chosen as the determining variable. To categorize social class, two classifications were used: Bronfman's classification and the classification used by the Brazilian Association of Market Research Institutes. Among the 934 women interviewed, 606 (65%) had had a Pap smear test in the 3 years before the study. The multivariate analysis revealed significant differences regarding performance of such tests in terms of social class, age, and frequency of medical consultations per year. No significant differences were found in terms of education, type of health service used, or hospitalizations during the year prior to the study. This study reveals that coverage of cervical cancer screening for women between 20 and 69 years of age in Pelotas is higher than the coverage found in other parts of the country or even of the world. However, for women in lower social classes, coverage was found to be between 52 and 56%. These data can contribute to the development of measures aimed at increasing cervical cancer screening among specific sectors of the population.

The question of whether the Sun is peculiar within the class of solar-type stars has been the subject of active investigation over the past three decades. Although several solar twins have been found with stellar parameters similar to those of the Sun (albeit in a range of Li abundances and with somewhat different compositions), their rotation periods are unknown, except for 18 Sco, which is younger than the Sun and with a rotation period shorter than solar. It is difficult to obtain rotation periods for stars of solar age from ground-based observations, as a low activity level imply a shallow rotational modulation of their light curves. CoRoT has provided space-based long time series from which the rotation periods of solar twins as old as the Sun could be estimated. Based on high S/N high resolution spectroscopic observations gathered at the Subaru Telescope, we show that the star CoRoT ID 102684698 (CoRoT Sol 1) is a somewhat evolved solar twin with a low Li abundance. Its rotation period is 29 +- 5 days, compatible with its age (6.7 Gyr) and low lithium content A(Li) < 0.85 dex. Interestingly, our CoRoT solar twin seems to have enhanced abundances of the refractory elements with respect to the Sun, a typical characteristic of most nearby twins. With a magnitude V ~14.1, ID 102684698 is the first solar twin revealed by CoRoT, the farthest field solar twin so far known, and the only solar twin older than the Sun for which a rotation period has been determined., 5 pages, 4 figures, 1 Table. Accepted to Astrophysical Journal Letters (ApJL): Manuscript #LET30652 press relesae: http://www.naoj.org/Pressrelease/list.html

We present rotation period measurements for subgiants observed by CoRoT. Interpreting the modulation of stellar light that is caused by star-spots on the time scale of the rotational period depends on knowing the fundamental stellar parameters. Constraints on the angular momentum distribution can be extracted from the true stellar rotational period. By using models with an internal angular momentum distribution and comparing these with measurements of rotation periods of subgiant stars we investigate the agreement between theoretical predictions and observational results. With this comparison we can also reduce the global stellar parameter space compatible with the rotational period measurements from subgiant light curves. We can prove that an evolution assuming solid body rotation is incompatible with the direct measurement of the rotational periods of subgiant stars. Measuring the rotation periods relies on two different periodogram procedures, the Lomb-Scargle algorithm and the Plavchan periodogram. Angular momentum evolution models were computed to give us the expected rotation periods for subgiants, which we compared with measured rotational periods. We find evidence of a sinusoidal signal that is compatible in terms of both phase and amplitude with rotational modulation. Rotation periods were directly measured from light curves for 30 subgiant stars and indicate a range of 30 to 100 d for their rotational periods. Our models reproduce the rotational periods obtained from CoRoT light curves. These new measurements of rotation periods and stellar models probe the non-rigid rotation of subgiant stars., Letter accepted for publication in Astronomy and Astrophysics. 4 pages, 4 figures 4 pages

The characterization of diabetic patients seen at a primary health care clinic.The case notes of 3,024 families were searched by means of a cross-sectional study for patients 30 to 75 years of age with a diagnosis of diabetes mellitus who had had a medical consultation during the previous five years. These patients were interviewed at their homes and were asked to come to the health center for physical examination and a plasma glucose test using glucosylated hemoglobin (GH).The prevalence of diabetes was 4%. The typical diabetic patient was a white women,or = 50 years of age, from a family with a monthly incomeor = 3 minimum wages. Compliance with GH was observed in 70% of the patients. Diet therapy was followed by less than one third of the patients and only one fifth were engaged in regular exercise. Nearly 70% were undergoing drug therapy (oral hypoglicemic agents or insulin); of these, only 15% used insulin. Most of the patients (66%) who agreed to have the GH test showed normal or fair glucose blood levels.Great efforts should be made by health teams to enhance diabetic patient education in order to promote compliance with recommendations regarding diet and exercise.

In 1995, cervical cancer was the fourth most important cause of death among women in the state of Rio Grande do Sul, Brazil. There are no available studies on Pap smear examination coverage in Pelotas, which is the largest city in the southern part of Rio Grande do Sul. Accordingly, in 1992 a population-based, cross-sectional study was carried out among 20 to 69 year-old women residing in urban areas of the city. The objectives of the study were to ascertain any Pap smear testing in the 3 years prior to the study, to determine the coverage of cervical cancer screening, and to identify any factors associated with the performance of Pap tests in Pelotas. Social class was chosen as the determining variable. To categorize social class, two classifications were used: Bronfman's classification and the classification used by the Brazilian Association of Market Research Institutes. Among the 934 women interviewed, 606 (65%) had had a Pap smear test in the 3 years before the study. The multivariate analysis revealed significant differences regarding performance of such tests in terms of social class, age, and frequency of medical consultations per year. No significant differences were found in terms of education, type of health service used, or hospitalizations during the year prior to the study. This study reveals that coverage of cervical cancer screening for women between 20 and 69 years of age in Pelotas is higher than the coverage found in other parts of the country or even of the world. However, for women in lower social classes, coverage was found to be between 52 and 56%. These data can contribute to the development of measures aimed at increasing cervical cancer screening among specific sectors of the population.

Rotational velocity, lithium abundance, and the mass depth of the outer convective zone are key parameters in the study of the processes at work in the stellar interior, in particular when examining the poorly understood processes operating in the interior of solar-analog stars. We investigate whether the large dispersion in the observed lithium abundances of solar-analog stars can be explained by the depth behavior of the outer convective zone masses, within the framework of the standard convection model based on the local mixing-length theory. We also aims to analyze the link between rotation and lithium abundance in solar-analog stars. We computed a new extensive grid of stellar evolutionary models, applicable to solar-analog stars, for a finely discretized set of mass and metallicity. From these models, the stellar mass, age, and mass depth of the outer convective zone were estimated for 117 solar-analog stars, using Teff and [Fe/H] available in the literature, and the new HIPPARCOS trigonometric parallax measurements. We determine the age and mass of the outer convective zone for a bona fide sample of 117 solar-analog stars. No significant on-to-one correlation is found between the computed convection zone mass and published lithium abundance, indicating that the large A(Li) dispersion in solar analogs cannot be explained by the classical framework of envelope convective mixing coupled with lithium depletion at the bottom of the convection zone. These results illustrate the need for an extra-mixing process to explain lithium behavior in solar-analog stars, such as, shear mixing caused by differential rotation. To derive a more realistic definition of solar-analog stars, as well as solar-twin, it seems important to consider the inner physical properties of stars, such as convection, hence rotation and magnetic properties., Comment: 9 pages, 7 figures