Characterizing genetic diversity in Africa is a crucial step for most analyses reconstructing the evolutionary history of anatomically modern humans. However, historic migrations from Eurasia into ...Africa have affected many contemporary populations, confounding inferences. Here, we present a 12.5× coverage ancient genome of an Ethiopian male ("Mota") who lived approximately 4500 years ago. We use this genome to demonstrate that the Eurasian backflow into Africa came from a population closely related to Early Neolithic farmers, who had colonized Europe 4000 years earlier. The extent of this backflow was much greater than previously reported, reaching all the way to Central, West, and Southern Africa, affecting even populations such as Yoruba and Mbuti, previously thought to be relatively unadmixed, who harbor 6 to 7% Eurasian ancestry.
Diffuse glow has been observed around brightly lit cities in nighttime satellite imagery since at least the first publication of large scale maps in the late 1990s. In the literature, this has often ...been assumed to be an error related to the sensor, and referred to as "blooming", presumably in relation to the effect that can occur when using a CCD to photograph a bright light source. Here we show that the effect seen on the DMSP/OLS, SNPP/VIIRS-DNB and ISS is not only instrumental, but in fact represents a real detection of light scattered by the atmosphere. Data from the Universidad Complutense Madrid sky brightness survey are compared to nighttime imagery from multiple sensors with differing spatial resolutions, and found to be strongly correlated. These results suggest that it should be possible for a future space-based imaging radiometer to monitor changes in the diffuse artificial skyglow of cities.
The capacity of two iron-based nanomaterials, namely goethite nanospheres (nGoethite) and zero valent iron nanoparticles (nZVI), to immobilize As in a polluted soil was evaluated and compared. The ...composition and morphology of the products were studied by energy dispersive X-ray analysis and transmission electron microscopy, while zeta potential and average sizes were determined by dynamic light scattering. To assess As immobilization, soil subsamples were treated with nGoethite or nZVI at a range of Fe doses (0.5%, 2%, 5% and 10%) and then studied by the TCLP test and the Tessier sequential extraction procedure. The influence of both nanoparticles on As speciation was determined, as was impact on soil pH, electrical conductivity, Fe availability and phytotoxicity (watercress germination). For nZVI, notable results were achieved at a dose of 2% (89.5% decrease in As, TCLP test), and no negative effects on soil parameters were detected. Indeed, even soil phytotoxicity was reduced and only at the highest dose was a slight increase in As3+ detected. In contrast, excellent results were obtained for nGoethite at the lowest dose (0.2%) (82.5% decrease in As, TCLP test); however, soil phytotoxicity was increased at higher doses, probably due to a marked enhancement of electrical conductivity. For both types of nanoparticle, slight increases in Fe availability were observed. Thus, our results show that both nZVI and nGoethite have the capacity to effectively immobilize As in this brownfield. The use of lower doses of nGoethite emerges as a promising soil remediation strategy for soils affected by As pollution.
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•NZVI and nGoethite immobilized As efficiently in a polluted soil.•Doses higher than 1% of nGoethite caused phytotoxicity.•Nanoparticle addition did not lead to a considerable increase in Fe availability.•NGoethite emerges as an interesting alternative to nZVI for As immobilization.
We describe a revised collection of the number of sunspot groups from 1610 to the present. This new collection is based on the work of Hoyt and Schatten (
Solar Phys
.
179
, 189,
1998
). The main ...changes are the elimination of a considerable number of observations during the Maunder Minimum (hereafter, MM) and the inclusion of several long series of observations. Numerous minor changes are also described. Moreover, we have calculated the active-day percentage during the MM from this new collection as a reliable index of the solar activity. Thus, the level of solar activity obtained in this work is greater than the level obtained using the original Hoyt and Schatten data, although it remains compatible with a grand minimum of solar activity. The new collection is available in digital format.
Nanoscale zero valent iron (nZVI) particles obtained by different methods differ in their structure, which lead to different reactivity, and therefore a likely difference in the remediation ...efficiency. The present study compares the effectiveness of three commercial ZVI nanoparticles to immobilize As and Hg in two soils (A and B) collected from a brownfield highly contaminated by mining and metallurgy activities. Scarce data are available on the effectiveness of nZVI for Hg immobilization in soil. Two commercial nZVI slurries from Toda (RNIP and RNIP-D) and one from Nano Iron (25S) were used at different doses (1, 5 and 10%). The metal(loid) availability and mobility was evaluated with the TCLP test and Tessier extraction procedure. The influence of nZVI application on As and Hg speciation was also evaluated as well as its impact on soil pH, electrical conductivity and soil phytotoxicity to vetch germination. The three commercial nZVI particles significantly reduced As and Hg availability in the two soils studied, which led to a decrease in soil phytotoxicity. At the dose of 5% of nZVI a decrease of exchangeable-As higher than 70% was observed for both soils, whereas in the case of Hg, a higher dose of nZVI (10%) was necessary to achieve reductions of exchangeable-Hg between 63 and 90% depending on the type of nZVI and soil. No impact on soil pH and electrical conductivity was observed. The effectiveness of metal(loid) immobilization depended on type of nZVI, soil properties and metal(loid) characteristics. Nanoparticles from Nano Iron showed better results for As immobilization whereas RNIP nanoparticles were more effective for Hg. Overall, 25S at the dose of 5% resulted more effective than RNIP nanoparticles for the reduction of exchangeable-As (in the range of 6–14%), whereas RNIP and RNIP-D were 10 and 13% more effective, respectively, for the reduction of exchangeable-Hg at the dose of 10% in soil B. Thus, nZVI can be used for the remediation of highly As and Hg polluted soils, although previous experiments at lab scale are necessary to determine the most viable type of nZVI and its dose.
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•Three types of commercial nZVI were tested in brownfield soil polluted with As and Hg.•nZVI reduced As and Hg availability in soil.•Different types of nZVI differed in effectiveness for As and Hg immobilization.•Soil properties affected nZVI effectiveness.
The alteration of normal biological rhythms, also known as chronodisruption, may be associated with obesity development. For instance, those subject with preference for vespertinity seem to be prone ...to develop obesity. However, the current hypocaloric dietary treatment of obesity does not take into account these aspects. Therefore, the objective of this trial was to evaluate whether a diet adjusted to patient's chronotype is more effective that the current dietary recommendations.
209 subjects take part on a 3 month randomized, double-blind trial. 104 subjects followed a typical hypocaloric dietary treatment and the other 105 subjects undergone a diet with a daily caloric distribution adjusted to their chronotype. There were no sex or age differences between groups.
Baseline characteristics were similar in both groups. Dropout rate was also similar in both interventions (p = 0.683). Although both groups improved their anthropometrical parameters, the chronotype-adjusted diet group achieved a statistically significant greater reduction in percentage of total body weight loss (%TWL), BMI and waist circumference than the control group (p < 0.010 in all contrasts). The effect on clinical parameters was less pronounced.
This randomized trial has demonstrated for the first time that in overweight/obese subjects, a chronotype-adjusted diet is more effective than the traditional hypocaloric dietary treatment, at least regarding the anthropometrical parameters. Further research will confirm if this intervention is also more effective in the long term.
NCT-ID: #NCT03755674, (available at: http://www.clinicaltrials.gov).
Traditionally, smear microscopy has been used to estimate bacillary burden in order to assess infectiousness in tuberculosis (TB) patients. Since Xpert MTB assays might replace smear microscopy as ...the first-line diagnostic test for pulmonary tuberculosis, an alternative measure of bacillary load that correlates with smear positivity is needed. This study assessed the correlation between C
(with and without normalization), smear status, culture time-to-positivity (TTP), and clinical factors in patients with Xpert ultra positive sputum during a four-year period. A cut-off C
value for smear positivity was also estimated. 204 samples were included. Strong correlation between both Xpert Ultra C
values (raw and normalized) and smear status was obtained (r = 0.78 and - 0.79, respectively). The association between Raw-C
and TTP was weaker than normalized-C
(N-C
) and TTP (r = 0.50 and r = - 0.70, respectively). A Raw-C
cut-off value of 21.4 was identified with 85.7% (95% CI 65.4-95) sensitivity and 92.9% (95% CI 84.3-96.9) specificity. A N-C
cut-off value of 5.2 yielded a sensitivity of 94.3% (95% CI 86.2-97.8) and specificity of 85.7% (95% CI 65.4-95). Our study demonstrates that Xpert Ultra C
value correlates well with other measures of bacillary load such as smear status or TTP. The correlation with TTP is stronger when the C
value is normalized using the internal control. The proposed N-C
cut-off value of 5.2 shows a better sensitivity than the Raw-CT when predicting smear positive status.
A
bstract
We construct a new class of metastable de Sitter vacua of flux compactifications of type IIB string theory. These solutions provide a natural extension of the ‘Large Volume Scenario’ ...anti-de Sitter vacua, and can analogously be realised at parametrically large volume and weak string coupling, using standard
N
= 1 supergravity. For these new vacua, a positive vacuum energy is achieved from the inclusion of a small amount of flux-induced supersymmetry breaking in the complex structure and axio-dilaton sector, and no additional ‘uplift’ contribution (e.g. from anti-branes) is required. We show that the approximate no-scale structure of the effective theory strongly influences the spectrum of the stabilised moduli: one complex structure modulus remains significantly lighter than the supersymmetry breaking scale, and metastability requires only modest amounts of tuning. After discussing these general results, we provide a recipe for constructing de Sitter vacua on a given compactification manifold, and give an explicit example of a de Sitter vacuum for the compactification on the Calabi-Yau orientifold realised in
ℂ
ℙ
11169
4
. Finally, we note that these solutions have intriguing implications for phenomenology, predicting no csuperpartners in the spectrum below ∼50 TeV, and no WIMP dark matter.
ABSTRACT
We revise the sunspot observations made by Galileo Galilei and Christoph Scheiner in the context of their controversy regarding the nature of sunspots. Those of their sunspot records not ...included in the current sunspot group database, used as a basis to calculate the sunspot group number, are analysed. Within the documentary sources consulted in this work, we can highlight the sunspot observations by Scheiner included in the letters sent under the pseudonym Apelles to Marcus Welser and the first sunspot observations made by Galileo, which can be consulted in Le opere di Galileo Galilei. These sunspot observations would extend the temporal coverage for these two observers and fill some gaps in the current group database in the earliest period, where the data available are sparse. Moreover, we have detected changes in the quality of the sunspot drawings made by Galileo and Scheiner in their observation series, affecting the number of groups recorded by the two observers. We also compare these records with sunspot observations made by other astronomers of that time. According to this comparison and regarding the same observation days, Scheiner was generally the astronomer who reported more sunspot groups, while Harriot, Cigoli and Galileo recorded a similar number of groups. We conclude that these differences are mainly because of the observational methods used by the observers.
ABSTRACT
The Maunder Minimum (MM) was a period of prolonged solar activity minimum between 1645 and 1715. Several works have identified a significant number of problematic spotless days in the MM ...included in existing data bases. We have found a list of exact spotless (in the second half of 1709) and spot days (January and August 1709) provided by Johann Heinrich Müller. We computed the most probable value and upper/lower limits of the active day fraction (ADF) from Müller's data using the hypergeometrical probability distribution. Our sample is not strictly random because Müller recorded observations in consecutive days when he observed sunspots. Therefore, our result represents an upper threshold of solar activity for 1709. We compared this result with annual values of the ADF calculated for the Dalton Minimum and the most recent solar cycles. We concluded that, although 1709 is one of the most active years in the MM, it was less active than most years both in the Dalton Minimum and in the most recent solar cycles. Therefore, the solar activity level estimated in this work for 1709 represents robust evidence of low solar activity levels in the MM.
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