Domestication has led to substantial phenotypic and genetic variation in domestic animals. In pigs, the size of so called minipigs differs by one order of magnitude compared to breeds of large body ...size. We used biallelic SNPs identified from re-sequencing data to compare various publicly available wild and domestic populations against two minipig breeds to gain better understanding of the genetic background of the extensive body size variation. We combined two complementary measures, expected heterozygosity and the composite likelihood ratio test implemented in "SweepFinder", to identify signatures of selection in Minipigs. We intersected these sweep regions with a measure of differentiation, namely F
, to remove regions of low variation across pigs. An extraordinary large sweep between 52 and 61 Mb on chromosome X was separately analyzed based on SNP-array data of F
individuals from a cross of Goettingen Minipigs and large pigs.
Selective sweep analysis identified putative sweep regions for growth and subsequent gene annotation provided a comprehensive set of putative candidate genes. A long swept haplotype on chromosome X, descending from the Goettingen Minipig founders was associated with a reduction of adult body length by 3% in F
cross-breds.
The resulting set of genes in putative sweep regions implies that the genetic background of body size variation in pigs is polygenic rather than mono- or oligogenic. Identified genes suggest alterations in metabolic functions and a possible insulin resistance to contribute to miniaturization. A size QTL located within the sweep on chromosome X, with an estimated effect of 3% on body length, is comparable to the largest known in pigs or other species. The androgen receptor AR, previously known to influence pig performance and carcass traits, is the most obvious potential candidate gene within this region.
Abstract
The ESA’s comet chaser Rosetta has monitored the evolution of the ionized atmosphere of comet 67P/Churyumov–Gerasimenko (67P/CG) and its interaction with the solar wind, during more than ...2 yr. Around perihelion, while the cometary outgassing rate was highest, Rosetta crossed hundreds of unmagnetized regions, but did not seem to have crossed a large-scale diamagnetic cavity as anticipated. Using in situ Rosetta observations, we characterize the structure of the unmagnetized plasma found around comet 67P/CG. Plasma density measurements from RPC-MIP are analysed in the unmagnetized regions identified with RPC-MAG. The plasma observations are discussed in the context of the cometary escaping neutral atmosphere, observed by ROSINA/COPS. The plasma density in the different diamagnetic regions crossed by Rosetta ranges from ∼100 to ∼1500 cm−3. They exhibit a remarkably systematic behaviour that essentially depends on the comet activity and the cometary ionosphere expansion. An effective total ionization frequency is obtained from in situ observations during the high outgassing activity phase of comet 67P/CG. Although several diamagnetic regions have been crossed over a large range of distances to the comet nucleus (from 50 to 400 km) and to the Sun (1.25–2.4 au), in situ observations give strong evidence for a single diamagnetic region, located close to the electron exobase. Moreover, the observations are consistent with an unstable contact surface that can locally extend up to about 10 times the electron exobase.
Context. The Rosetta magnetometer RPC-MAG has been exploring the plasma environment of comet 67P/Churyumov-Gerasimenko since August 2014. The first months were dominated by low-frequency waves which ...evolved into more complex features. However, at the end of July 2015, close to perihelion, the magnetometer detected a region that did not contain any magnetic field at all. Aims. These signatures match the appearance of a diamagnetic cavity as was observed at comet 1P/Halley in 1986. The cavity here is more extended than previously predicted by models and features unusual magnetic field configurations, which need to be explained. Methods. The onboard magnetometer data were analyzed in detail and used to estimate the outgassing rate. A minimum variance analysis was used to determine boundary normals. Results. Our analysis of the data acquired by the Rosetta Plasma Consortium instrumentation confirms the existence of a diamagnetic cavity. The size is larger than predicted by simulations, however. One possible explanation are instabilities that are propagating along the cavity boundary and possibly a low magnetic pressure in the solar wind. This conclusion is supported by a change in sign of the Sun-pointing component of the magnetic field. Evidence also indicates that the cavity boundary is moving with variable velocities ranging from 230−500 m/s.
We use measurements from the Rosetta plasma consortium Langmuir probe and mutual impedance probe to study the spatial distribution of low‐energy plasma in the near‐nucleus coma of comet ...67P/Churyumov‐Gerasimenko. The spatial distribution is highly structured with the highest density in the summer hemisphere and above the region connecting the two main lobes of the comet, i.e., the neck region. There is a clear correlation with the neutral density and the plasma to neutral density ratio is found to be ∼1–2·10−6, at a cometocentric distance of 10 km and at 3.1 AU from the Sun. A clear 6.2 h modulation of the plasma is seen as the neck is exposed twice per rotation. The electron density of the collisionless plasma within 260 km from the nucleus falls off with radial distance as ∼1/r. The spatial structure indicates that local ionization of neutral gas is the dominant source of low‐energy plasma around the comet.
Key Points
The spatial distribution of plasma around comet 67P is highly structured
Local ionization of neutral gas dominates the plasma environment
Plasma falls off with cometocentric distance as 1/r
Galactic winds are a prime suspect for the metal enrichment of the intergalactic medium (IGM) and may have a strong influence on the chemical evolution of galaxies and the nature of QSO ...absorption-line systems. We use a sample of 1406 galaxy spectra at z ~ 1.4 from the DEEP2 redshift survey to show that blueshifted Mg IYI lambda lambda 2796, 2803 absorption is ubiquitous in star-forming galaxies at this epoch. This is the first detection of frequent outflowing galactic winds at z ~ 1. The presence and depth of absorption are independent of active galactic nuclei spectral signatures or galaxy morphology; major mergers are not a prerequisite for driving a galactic wind from massive galaxies. Outflows are found in co-added spectra of galaxies spanning a range of 30 times in stellar mass and 10 times in star formation rate (SFR), calibrated from K-band and from the Multiband Imaging Photometer for Spitzer IR fluxes. The outflows have column densities of order NH ~ 1020 cm-2 and characteristic velocities of ~ 300-500 km s-1, with absorption seen out to 1000 km s-1 in the most massive, highest SFR galaxies. The velocities suggest that the outflowing gas can escape into the IGM and that massive galaxies can produce cosmologically and chemically significant outflows. Both the Mg II equivalent width and the outflow velocity are larger for galaxies of higher stellar mass and SFR, with V wind ~ SFR0.3, similar to the scaling in low redshift IR-luminous galaxies. The high frequency of outflows in the star-forming galaxy population at z ~ 1 indicates that galactic winds occur in the progenitors of massive spirals as well as those of ellipticals. The increase of outflow velocity with mass and SFR constrains theoretical models of galaxy evolution that include feedback from galactic winds, and may favor momentum-driven models for the wind physics.
The largest submarine volcanic eruption of this century led to a dramatic phytoplankton bloom north of the island of Tongatapu, in the Kingdom of Tonga. In the absence of shipboard observations, we ...reconstructed the dynamics of this event by using a suite of satellite observations. Two independent bio‐optical approaches confirmed that the phytoplankton bloom was a robust observation and not an optical artifact due to volcanogenic material. Furthermore, the timing, size, and position of the phytoplankton bloom suggest that plankton growth was primarily stimulated by nutrients released from volcanic ash rather than by nutrients upwelled through submarine volcanic activity. The appearance of a large region with high chlorophyll a concentrations <48 hr after the largest eruptive phase indicates a fast ecosystem response to nutrient fertilization. However, net phytoplankton growth probably initiated before the main eruption, when weaker volcanism had already fertilized the ocean.
Plain Language Summary
In January 2022, the Hunga Tonga‐Hunga Haʻapai volcano was responsible for the largest submarine eruption of this century, which emitted large amounts of nutrients into the ocean. After the eruption, when the volcanic plume dissipated, satellite measurements of the light reflected from the sea surface revealed a 10‐fold increase in phytoplankton near the volcano. Phytoplankton are the microscopic photosynthetic organisms drifting in seawater that produce oxygen and serve as the base of the marine food web. The growth of these organisms is often limited by the low concentrations of nutrients dissolved in the surface ocean, but phytoplankton can increase rapidly when nutrients become available. Even though the Hunga Tonga‐Hunga Haʻapai eruption was submarine, a large plume of ash reached a height of tens of kilometers into the atmosphere so that nutrients were supplied both through the water rising from the caldera and through ash fallout. We propose that the latter was the most important source of nutrients responsible for phytoplankton growth.
Key Points
An extensive phytoplankton bloom was observed <2 days after the main eruption
Ocean fertilization through volcanic ash deposition likely fueled the bloom
Strong temperature anomalies indicate localized volcanogenic upwelling near the caldera
Abstract Introduction A diagnostic gap exists in the current dual photon X-ray absorptiometry (DXA) based diagnostic approach to osteoporosis. Other diagnostic devices have been developed, but no ...comprehensive review concerning the applicability of these diagnostic devices for population-based screening have been performed. Material and
m
ethods A systematic review of Embase, Medline and the Cochrane Central Register for Controlled Trials was performed for population-based studies that focused on technical methods that could either indicate bone mineral density (BMD) by DXA, substitute for DXA in prediction of fracture risk, or that could have an incremental value in fracture prediction in addition to DXA. Quality of included studies was rated by QUADAS 2. Results Many other technical devices have been tested in a population-based setting. Five studies aiming to indicate BMD and 17 studies aiming to predict fractures were found. Overall, the latter studies had higher methodological quality. The highest number of studies was found for quantitative ultrasound (QUS). The ability to indicate BMD or predict fractures was moderate to minor for all examined devices, using reported
a
rea
u
nder the
c
urve (AUC) of Receiver Operating Characteristic curves values as standard. Conclusions Of the methods assessed, only QUS appears capable of perhaps replacing DXA as standalone examination in the future whilst radiographic absorptiometry could provide important information in areas with scarcity of DXA. QUS may be of added value even after DXA has been performed. Evaluation of proposed cutoff-values from population-based studies in separate population-based cohorts is still lacking for most examination devices.
Summary
The Risk-stratified Osteoporosis Strategy Evaluation (ROSE) study investigated the effectiveness of a two-step screening program for osteoporosis in women. We found no overall reduction in ...fractures from systematic screening compared to the current case-finding strategy. The group of moderate- to high-risk women, who accepted the invitation to DXA, seemed to benefit from the program.
Introduction
The purpose of the ROSE study was to investigate the effectiveness of a two-step population-based osteoporosis screening program using the Fracture Risk Assessment Tool (FRAX) derived from a self-administered questionnaire to select women for DXA scan. After the scanning, standard osteoporosis management according to Danish national guidelines was followed.
Methods
Participants were randomized to either screening or control group, and randomization was stratified according to age and area of residence. Inclusion took place from February 2010 to November 2011. Participants received a self-administered questionnaire, and women in the screening group with a FRAX score ≥ 15% (major osteoporotic fractures) were invited to a DXA scan. Primary outcome was incident clinical fractures. Intention-to-treat analysis and two per-protocol analyses were performed.
Results
A total of 3416 fractures were observed during a median follow-up of 5 years. No significant differences were found in the intention-to-treat analyses with 34,229 women included aged 65–80 years. The per-protocol analyses showed a risk reduction in the group that underwent DXA scanning compared to women in the control group with a FRAX ≥ 15%, in regard to major osteoporotic fractures, hip fractures, and all fractures. The risk reduction was most pronounced for hip fractures (adjusted SHR 0.741,
p
= 0.007).
Conclusions
Compared to an office-based case-finding strategy, the two-step systematic screening strategy had no overall effect on fracture incidence. The two-step strategy seemed, however, to be beneficial in the group of women who were identified by FRAX as moderate- or high-risk patients and complied with DXA.
We report on magnetic field measurements made in the innermost coma of 67P/Churyumov-Gerasimenko in its low-activity state. Quasi-coherent, large-amplitude (δ B/B ~ 1), compressional magnetic field ...oscillations at ~ 40 mHz dominate the immediate plasma environment of the nucleus. This differs from previously studied cometary interaction regions where waves at the cometary ion gyro-frequencies are the main feature. Thus classical pickup-ion-driven instabilities are unable to explain the observations. We propose a cross-field current instability associated with newborn cometary ion currents as a possible source mechanism.
Methods for assembly, taxonomic profiling and binning are key to interpreting metagenome data, but a lack of consensus about benchmarking complicates performance assessment. The Critical Assessment ...of Metagenome Interpretation (CAMI) challenge has engaged the global developer community to benchmark their programs on highly complex and realistic data sets, generated from ∼700 newly sequenced microorganisms and ∼600 novel viruses and plasmids and representing common experimental setups. Assembly and genome binning programs performed well for species represented by individual genomes but were substantially affected by the presence of related strains. Taxonomic profiling and binning programs were proficient at high taxonomic ranks, with a notable performance decrease below family level. Parameter settings markedly affected performance, underscoring their importance for program reproducibility. The CAMI results highlight current challenges but also provide a roadmap for software selection to answer specific research questions.
PDF
