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Population History and Gene Divergence in Native Mexicans Inferred from 76 Human Exomes.
Native American genetic variation remains underrepresented in most catalogs of human genome sequencing data. Previous genotyping efforts have revealed that Mexico's Indigenous population is highly differentiated and substructured, thus potentially harboring higher proportions of private genetic variants of functional and biomedical relevance. Here we have targeted the coding fraction of the genome and characterized its full site frequency spectrum by sequencing 76 exomes from five Indigenous populations across Mexico. Using diffusion approximations, we modeled the demographic history of Indigenous populations from Mexico with northern and southern ethnic groups splitting 7.2 KYA and subsequently diverging locally 6.5 and 5.7 KYA, respectively. Selection scans for positive selection revealed BCL2L13 and KBTBD8 genes as potential candidates for adaptive evolution in Rarámuris and Triquis, respectively. BCL2L13 is highly expressed in skeletal muscle and could be related to physical endurance, a well-known phenotype of the northern Mexico Rarámuri. The KBTBD8 gene has been associated with idiopathic short stature and we found it to be highly differentiated in Triqui, a southern Indigenous group from Oaxaca whose height is extremely low compared to other Native populations
Small-spatial scale variations of nebular properties and the abundance discrepancy in three Galactic HII regions
We present results of long-slit spectroscopy in several slit positions that
cover different morphological structures of the central parts of three bright
Galactic HII regions: M8, M17 and NGC7635. We study the spatial distributions
of a large number of nebular parameters such as the extinction coefficient,
line fluxes, physical conditions and ionic abundances at the maximum spatial
resolution attainable with our instrumentation. Particularly, our goal is to
study the behaviour of the abundance discrepancy factor of O^{2+}, ADF(O^{2+}),
defined as the logarithmic difference of the O^{2+} abundances derived from
collisionally excited and recombination lines. We find that the ADF(O^{2+})
remains fairly constant along the slit positions of M8 and M17. In the case of
NGC7635, we only detect the OII recombination lines in the integrated spectrum
along the whole slit, where the ADF(O^{2+}) reaches a remarkably high value of
about 0.59 dex. We compare our results with previous ones obtained for the
Orion Nebula. We find several evidences that suggest the presence of a
candidate to Herbig-Haro object in M8.Comment: 18 pages, 9 figures. Table A1 available only in the online version.
Accepted for publication in MNRAS
Carbon and oxygen in HII regions of the Magellanic Clouds: abundance discrepancy and chemical evolution
We present C and O abundances in the Magellanic Clouds derived from deep
spectra of HII regions. The data have been taken with the Ultraviolet-Visual
Echelle Spectrograph at the 8.2-m VLT. The sample comprises 5 HII regions in
the Large Magellanic Cloud (LMC) and 4 in the Small Magellanic Cloud (SMC). We
measure pure recombination lines (RLs) of CII and OII in all the objects,
permitting to derive the abundance discrepancy factors (ADFs) for O^2+, as well
as their O/H, C/H and C/O ratios. We compare the ADFs with those of other HII
regions in different galaxies. The results suggest a possible metallicity
dependence of the ADF for the low-metallicity objects, but more uncertain for
high-metallicity objects. We compare nebular and B-type stellar abundances and
we find that the stellar abundances agree better with the nebular ones derived
from collisionally excited lines (CELs). Comparing these results with other
galaxies we observe that stellar abundances seem to agree better with the
nebular ones derived from CELs in low-metallicity environments and from RLs in
high-metallicity environments. The C/H, O/H and C/O ratios show almost flat
radial gradients, in contrast with the spiral galaxies where such gradients are
negative. We explore the chemical evolution analysing C/O vs. O/H and comparing
with the results of HII regions in other galaxies. The LMC seems to show a
similar chemical evolution to the external zones of small spiral galaxies and
the SMC behaves as a typical star-forming dwarf galaxy.Comment: Accepted for publication in MNRAS, 17 pages, 11 figures, 8 table
Structural stability of SiGe nanoparticles under "in situ" electron beam irradiation in TEM
The structure of amorphous and crystalline SiGe nanoparticles, embedded in a
dielectric medium, SiO2, and its stability under “in situ” electron beam irradiation is reported.
High-resolution transmission electron microscopy and electron-diffraction pattern simulation
by fast Fourier transform was used to analyze the crystal structure of the SiGe nanoparticles.
Electron beam irradiation induces structural alternate order-disorder transitions in the
nanoparticles for irradiation effects are mainly associated to the density of current. For
irradiation with current densities < 7 A·cm-2 no effects are observed in the as-deposited
amorphous samples, whereas in the crystallized samples, SiGe nanocrystals show higher
stability and no effects are observed for irradiation densities of current < 50 A·cm-2. Irradiation
with densities of current greater than these thresholds cause consecutive amorphous-crystalline
or crystalline-amorphous structure transitions respectively for both amorphous and crystallized
nanoparticles. A hexagonal structure is proposed for those nanocrystals obtained after
irradiation in the as deposited amorphous samples
Functional correlates of response inhibition in impulse control disorders in Parkinson’s disease
Available online 11 September 2021.Impulse control disorder is a prevalent side-effect of Parkinson’s disease (PD) medication, with a strong negative
impact on the quality of life of those affected. Although impulsivity has classically been associated with response
inhibition deficits, previous evidence from PD patients with impulse control disorder (ICD) has not revealed
behavioral dysfunction in response inhibition. In this study, 18 PD patients with ICD, 17 PD patients without this
complication, and 15 healthy controls performed a version of the conditional Stop Signal Task during functional
magnetic resonance imaging. Whole-brain contrasts, regions of interest, and functional connectivity analyses
were conducted. Our aim was to investigate the neural underpinnings of two aspects of response inhibition:
proactive inhibition, inhibition that has been prepared beforehand, and restrained inhibition, inhibition of an
invalid inhibitory tendency. We observed that, in respect to the other two groups, PD patients with ICD exhibited
hyperactivation of the stopping network bilaterally while performing proactive inhibition. When engaged in
restrained inhibition, they showed hyperactivation of the left inferior frontal gyrus, an area linked to action
monitoring. Restrained inhibition also resulted in changes to the functional co-activation between inhibitory
regions and left inferior parietal cortex and right supramarginal gyrus. Our findings indicate that PD patients
with ICD completed the inhibition task correctly, showing altered engagement of inhibitory and attentional
areas. During proactive inhibition they showed bilateral hyperactivation of two inhibitory regions, while during
restrained inhibition they showed additional involvement of attentional areas responsible for alerting and
orienting.This work was supported by grants from the Carlos III Institute of
Health (PI11/02109) and the ERA-Neuron program (PIM2010ERN-
0033). Additionally, the authors received the following grants and
honoraria: T.E.-P. received a grant from the Spanish Ministry of Economy
and Competitiveness (BES-2016-079489). P.M.P.-A. was supported
by grants from the Spanish Ministry of Economy and Competitiveness
(RYC-2014-15440), the Spanish Ministry of Science and Innovation
(PGC2018-093408-B-I00), and the Fundación Tatiana Pérez de Guzmán
el Bueno. I.N.-G. was the recipient of a Rio Hortega grant (CM16/00033)
from the Carlos III Institute of Health. I.N.-G. received honoraria from
Zambon and TEVA for travel and accommodation to attend scientific
meetings. M.C.R.-O. received financial support for her research from
national and local government institutions in Spain (Carlos III Institute
of Health, Basque Country Government, Diputacion Foral Guipuzcoa,
and CIBERNED). M.C.R.-O. received honoraria from Zambon, Bial, and
Boston Scientific for lectures, travel, and accommodation to attend scientific
meetings. BCBL acknowledges support from the Basque Government
through the BERC 2018-2021 program
Functional correlates of response inhibition in impulse control disorders in Parkinson’s disease
Available online 11 September 2021.Impulse control disorder is a prevalent side-effect of Parkinson’s disease (PD) medication, with a strong negative
impact on the quality of life of those affected. Although impulsivity has classically been associated with response
inhibition deficits, previous evidence from PD patients with impulse control disorder (ICD) has not revealed
behavioral dysfunction in response inhibition. In this study, 18 PD patients with ICD, 17 PD patients without this
complication, and 15 healthy controls performed a version of the conditional Stop Signal Task during functional
magnetic resonance imaging. Whole-brain contrasts, regions of interest, and functional connectivity analyses
were conducted. Our aim was to investigate the neural underpinnings of two aspects of response inhibition:
proactive inhibition, inhibition that has been prepared beforehand, and restrained inhibition, inhibition of an
invalid inhibitory tendency. We observed that, in respect to the other two groups, PD patients with ICD exhibited
hyperactivation of the stopping network bilaterally while performing proactive inhibition. When engaged in
restrained inhibition, they showed hyperactivation of the left inferior frontal gyrus, an area linked to action
monitoring. Restrained inhibition also resulted in changes to the functional co-activation between inhibitory
regions and left inferior parietal cortex and right supramarginal gyrus. Our findings indicate that PD patients
with ICD completed the inhibition task correctly, showing altered engagement of inhibitory and attentional
areas. During proactive inhibition they showed bilateral hyperactivation of two inhibitory regions, while during
restrained inhibition they showed additional involvement of attentional areas responsible for alerting and
orienting.This work was supported by grants from the Carlos III Institute of
Health (PI11/02109) and the ERA-Neuron program (PIM2010ERN-
0033). Additionally, the authors received the following grants and
honoraria: T.E.-P. received a grant from the Spanish Ministry of Economy
and Competitiveness (BES-2016-079489). P.M.P.-A. was supported
by grants from the Spanish Ministry of Economy and Competitiveness
(RYC-2014-15440), the Spanish Ministry of Science and Innovation
(PGC2018-093408-B-I00), and the Fundación Tatiana Pérez de Guzmán
el Bueno. I.N.-G. was the recipient of a Rio Hortega grant (CM16/00033)
from the Carlos III Institute of Health. I.N.-G. received honoraria from
Zambon and TEVA for travel and accommodation to attend scientific
meetings. M.C.R.-O. received financial support for her research from
national and local government institutions in Spain (Carlos III Institute
of Health, Basque Country Government, Diputacion Foral Guipuzcoa,
and CIBERNED). M.C.R.-O. received honoraria from Zambon, Bial, and
Boston Scientific for lectures, travel, and accommodation to attend scientific
meetings. BCBL acknowledges support from the Basque Government
through the BERC 2018-2021 program
Effects of dry needling on gait and muscle tone in Parkinson''s disease: a randomized clinical trial
Background: Alterations in gait and muscular rigidity are common and disabling in persons with Parkinson''s disease (PD). Objective: The aim of this study was to determine whether a single dry needling (DN) session can promote changes in gait and muscle tone in the lower extremities as well as in the evolution of the disease in persons with PD. Methods: A randomized double-blind clinical trial was designed. Participants were randomly assigned to an intervention group (IG) that received a session of DN over the semitendinosus, medial gastrocnemius, soleus and rectus femoris muscles, or to a control group (CG) that received a session of sham DN in the same muscles. The effects of DN were assessed using the timed up and go test (TUG), 10 meter walk test (10MWT), 6 minute walk test (6MWT) and myotonometry before, immediately after, and 7 days after the intervention. Results: Thirty-three participants were analyzed aged 69.9 +/- 7.2 years (mean +/- SD; 39% female). There were no significant differences between the IG and CG for any outcomes. Significant differences were observed when comparing the Pre and Follow-up values in the IG for functional mobility of gait in the TUG (p = 0.049), gait speed in the 10MWT (p = 0.041) and muscle tone in the lower extremities by myotonometry (frequency (p = 0.027) and stiffness (p = 0.013)). By comparison, there were no significant within-group differences in the CG. Conclusion: A single session of DN had no measurable benefit compared to a single session of sham DN. Within-group changes in the IG suggested improvements in functional mobility of gait and gait speed, as well as changes in the muscle tone in the lower extremities of PD patients, which could be worthy of further exploration by future research
Elimination of trace organics in an MBR/RO system for water reuse
An intensive programme for detection of trace organics was performed in a membrane bioreactor
(MBR) plant in Almuñécar (south of Spain) over 1 year. The compounds investigated included 15
pharmaceutically active compounds, 12 polycyclic aromatic hydrocarbons and eight other compounds
(nonylphenols, linear alkylbenzene sulphonates and phthalates). The MBR operated with two lines
in parallel using a hollow fibre and a flat sheet membrane respectively. Additionally, a reverse osmosis
(RO) plant treated the MBR permeate over 1 month and the elimination of trace organics by the MBR/
RO system was assessed. The elimination efficiency of trace organics by the MBR was similar to that
found in a conventional activated sludge plant treating the same influent. The concentration of trace
organics was reduced after the MBR to a great extent and no significant differences were found
between the two lines operating in parallel. The elimination efficiency increased up to 80–100% after
passing the RO system. The results indicated that the MBR effluent reached the standard required by
the Spanish Royal Decree for Water Reuse and can therefore be reused for multiple purposes, but
advanced treatment like RO is necessary when the highest effluent quality is required
Properties of the ionized gas in HH202. II: Results from echelle spectrophotometry with UVES
We present results of deep echelle spectrophotometry of the brightest knot of
the HH202 in the Orion Nebula --HH202-S-- using the ultraviolet Visual Echelle
Spectrograph (UVES). The high spectral resolution has permitted to separate the
component associated with the ambient gas from that associated with the gas
flow. We derive electron densities and temperatures for both components, as
well as the chemical abundances of several ions and elements from collisionally
excited lines, including the first determinations of Ca^{+} and Cr^{+}
abundances in the Orion Nebula. We also calculate the He^{+}, C^{2+}, O^{+} and
O^{2+} abundances from recombination lines. The difference between the O^{2+}
abundances determined from collisionally excited and recombination lines --the
so-called abundance discrepancy factor-- is 0.35 dex and 0.11 dex for the shock
and nebular components, respectively. Assuming that the abundance discrepancy
is produced by spatial variations in the electron temperature, we derive values
of the temperature fluctuation parameter, t^2, of 0.050 and 0.016, for the
shock and nebular components, respectively. Interestingly, we obtain almost
coincident t^2 values for both components from the analysis of the intensity
ratios of He I lines. We find significant departures from case B predictions in
the Balmer and Paschen flux ratios of lines of high principal quantum number n.
We analyze the ionization structure of HH202-S, finding enough evidence to
conclude that the flow of HH202-S has compressed the ambient gas inside the
nebula trapping the ionization front. We measure a strong increase of the total
abundances of nickel and iron in the shock component, the abundance pattern and
the results of photoionization models for both components are consistent with
the partial destruction of dust after the passage of the shock wave in HH202-S.Comment: 23 pages, 7 figures. Accepted for publication in MNRA
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