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Habitat selection of animals is influenced by spatial heterogeneity as well as temporal environmental dynamics. In addition, human activities potentially have severe influences on the habitat selection of animals, often resulting in more nocturnal behavior. We investigated seasonal and circadian habitat selection patterns of red deer (Cervus elaphus) on a military training area in Bavaria (Germany). Individual deer ranged on two neighboring, but non-overlapping sites differing in landscape composition and human activity. Using GPS telemetry data, we visually investigated selection patterns and then fitted step-selection functions to assess multiple approaches to account for temporal (i.e., diel and seasonal) effects and for the impact of habitat conditions on selection. We first showed that the way in which time of day is considered in step-selection functions is essential for obtaining ecologically meaningful results, and that the usual ways of including time (i.e., either based on clock-time or based on night vs. day categories) can lead to incomplete or misleading conclusions. Furthermore, we found that individuals followed either circadian or seasonal habitat selection patterns, depending on the site they inhabited. This can be explained by differences in disturbance between the two sites. Except in winter, individuals selected for open habitats during the night irrespective of human activity level, but only individuals from the more disturbed site selected for covered habitats during the day. Our results highlight the importance of carefully considering the appropriate temporal scale for habitat selection analyses. Our findings also indicate that red deer are not a crepuscular or nocturnal species per se, as is often observed in human-dominated landscapes. Instead, our results imply that nocturnality in red deer is an effect of adaption to human activities.

To determine if patients with post-polio syndrome (PPS) show spinal cord gray matter (SCGM) atrophy and to assess associations between SCGM atrophy, muscle strength and patient-reported functional decline.Twenty patients diagnosed with PPS (March of Dimes criteria) and 20 age- and sex-matched healthy controls (HC) underwent 3T axial 2D-rAMIRA magnetic resonance imaging at the intervertebral disc levels C2/C3-C6/C7, T9/T10 and the lumbar enlargement level (TPost-polio syndrome patients showed significantly and preferentially reduced SCGM areas at C2/C3 (p = 0.048), C3/C4 (p = 0.001), C4/C5 (p 0.001), C5/C6 (p = 0.004) and TPatients with PPS show significant SCGM atrophy that correlates with muscle strength and is associated with PPS-related functional decline. Our findings suggest a secondary neurodegenerative process underlying SCGM atrophy in PPS that is not explained by aging or residua of the initial infection alone. Confirmation by longitudinal studies is needed. The described imaging methodology is promising for developing novel imaging surrogates for SCGM diseases.

Background: MR imaging of the spinal cord (SC) gray matter (GM) at the cervical and lumbar enlargements' level may be particularly informative in lower motor neuron disorders, e. g., spinal muscular atrophy, but also in other neurodegenerative or autoimmune diseases affecting the SC. Radially sampled averaged magnetization inversion recovery acquisition (rAMIRA) is a novel approach to perform SC imaging in clinical settings with favorable contrast and is well-suited for SC GM quantitation. However, before applying rAMIRA in clinical studies, it is important to understand (i) the sources of inter-subject variability of total SC cross-sectional areas (TCA) and GM area (GMA) measurements in healthy subjects and (ii) their relation to age and sex to facilitate the detection of pathology-associated changes. In this study, we aimed to develop normalization strategies for rAMIRA-derived SC metrics using skull and spine-based metrics to reduce anatomical variability.Methods: Sixty-one healthy subjects (age range 11–93 years, 37.7% women) were investigated with axial two-dimensional rAMIRA imaging at 3T MRI. Cervical and thoracic levels including the level of the cervical (C4/C5) and lumbar enlargements (Tmax) were examined. SC T2-weighted sagittal images and high-resolution 3D whole-brain T1-weighted images were acquired. TCA and GMAs were quantified. Anatomical variables with associations of |r| > 0.30 in univariate association with SC areas, and age and sex were used to construct normalization models using backward selection with TCAC4/C5 as outcome. The effect of the normalization was assessed by % relative standard deviation (RSD) reductions.Results: Mean inter-individual variability and the SD of the SC area metrics were considerable: TCAC4/5: 8.1%/9.0; TCATmax: 8.9%/6.5; GMAC4/C5: 8.6%/2.2; GMATmax: 12.2%/3.8. Normalization based on sex, brain WM volume, and spinal canal area resulted in RSD reductions of 23.7% for TCAs and 12.0% for GM areas at C4/C5. Normalizations based on the area of spinal canal alone resulted in RSD reductions of 10.2% for TCAs and 9.6% for GM areas at C4/C5, respectively.Discussion: Anatomic inter-individual variability of SC areas is substantial. This study identified effective normalization models for inter-subject variability reduction in TCA and SC GMA in healthy subjects based on rAMIRA imaging.

Dwarf spheroidal (dSph) galaxies are key objects in near-field cosmology, especially in connection to the study of galaxy formation and evolution at small scales. In addition, dSphs are optimal targets to investigate the nature of dark matter. However, while we begin to have deep optical photometric observations of the stellar population in these objects, little is known so far about their diffuse emission at any observing frequency, and hence on thermal and non-thermal plasma possibly residing within dSphs. In this paper, we present deep radio observations of six local dSphs performed with the Australia Telescope Compact Array at 16 cm wavelength. We mosaiced a region of radius of about one degree around three "classical" dSphs, Carina, Fornax, and Sculptor, and of about half of degree around three "ultra-faint" dSphs, BootesII, Segue2, and Hercules. The rms noise level is below 0.05 mJy for all the maps. The restoring beams FWHM ranged from 4.2 x 2.5 arcseconds to 30.0 x 2.1 arcseconds in the most elongated case. A catalogue including the 1392 sources detected in the six dSph fields is reported. The main properties of the background sources are discussed, with positions and fluxes of brightest objects compared with the FIRST, NVSS, and SUMSS observations of the same fields. The observed population of radio emitters in these fields is dominated by synchrotron sources. We compute the associated source number counts at 2 GHz down to fluxes of 0.25 mJy, which prove to be in agreement with AGN count models., Comment: 18 pages, 9 figure panels. Companion papers: arXiv:1407.5482 and arXiv:1407.4948. v3: minor revision, matches version accepted in MNRAS

We present a deep radio search in the Reticulum II dwarf spheroidal (dSph) galaxy performed with the Australia Telescope Compact Array. Observations were conducted at 16 cm wavelength, with an rms sensitivity of 0.01 mJy/beam, and with the goal of searching for synchrotron emission induced by annihilation or decay of weakly interacting massive particles (WIMPs). Data were complemented with observations on large angular scales taken with the KAT-7 telescope. We find no evidence for a diffuse emission from the dSph and we derive competitive bounds on the WIMP properties. In addition, we detect more than 200 new background radio sources. Among them, we show there are two compelling candidates for being the radio counterpart of the possible gamma-ray emission reported by other groups using Fermi-LAT data., 24 pages, 13 figure panels, 2 tables. v2 to match published version

Severe persistent pruritus is a common, but incompletely characterized, complication of hydroxyethyl starch (HES) infusion. This retrospective study aimed to assess HES-induced pruritus by electron microscopic findings, pruritus characteristics, and response to stimuli, and to determine the impact of HES dosage, molecular weight and substitution. Seventy patients with electron micro-scopy-proven HES-induced pruritus were included. HES-laden vacuoles were observed in skin macrophages of all patients. The median latency between HES exposure and pruritus onset was 3 weeks, and the median duration of pruritus was 6 months. Pruritus was severe, or very severe, in 80% of patients. Mechanical stimuli triggered pruritus in 74% of patients. Although the median cumulative dose of HES was 300 g, 15% of patients developed pruritus after only 30 g. There were no significant differences between HES 130/0.4 and HES 200/0.5 in pruritus latency, duration or severity. HES-induced pruritus thus may occur at any dose, molecular weight or substitution.

SummaryInduced pluripotent stem cells (iPSCs) outwardly appear to be indistinguishable from embryonic stem cells (ESCs). A study of gene expression profiles of mouse and human ESCs and iPSCs suggests that, while iPSCs are quite similar to their embryonic counterparts, a recurrent gene expression signature appears in iPSCs regardless of their origin or the method by which they were generated. Upon extended culture, hiPSCs adopt a gene expression profile more similar to hESCs; however, they still retain a gene expression signature unique from hESCs that extends to miRNA expression. Genome-wide data suggested that the iPSC signature gene expression differences are due to differential promoter binding by the reprogramming factors. High-resolution array profiling demonstrated that there is no common specific subkaryotypic alteration that is required for reprogramming and that reprogramming does not lead to genomic instability. Together, these data suggest that iPSCs should be considered a unique subtype of pluripotent cell.

The potential for directed differentiation of human-induced pluripotent stem (iPS) cells to functional postmitotic neuronal phenotypes is unknown. Following methods shown to be effective at generating motor neurons from human embryonic stem cells (hESCs), we found that once specified to a neural lineage, human iPS cells could be differentiated to form motor neurons with a similar efficiency as hESCs. Human iPS-derived cells appeared to follow a normal developmental progression associated with motor neuron formation and possessed prototypical electrophysiological properties. This is the first demonstration that human iPS-derived cells are able to generate electrically active motor neurons. These findings demonstrate the feasibility of using iPS-derived motor neuron progenitors and motor neurons in regenerative medicine applications and in vitro modeling of motor neuron diseases. Disclosure of potential conflicts of interest is found at the end of this article.

Our closest neighbours, the Local Group dwarf spheroidal (dSph) galaxies, are extremely quiescent and dim objects, where thermal and non-thermal diffuse emissions lack, so far, of detection. In order to possibly study the dSph interstellar medium, deep observations are required. They could reveal non-thermal emissions associated with the very-low level of star formation, or to particle dark matter annihilating or decaying in the dSph halo. In this work, we employ radio observations of six dSphs, conducted with the Australia Telescope Compact Array in the frequency band 1.1-3.1 GHz, to test the presence of a diffuse component over typical scales of few arcmin and at an rms sensitivity below 0.05 mJy/beam. We observed the dSph fields with both a compact array and long baselines. Short spacings led to a synthesized beam of about 1 arcmin and were used for the extended emission search. The high-resolution data mapped background sources, which in turn were subtracted in the short-baseline maps, to reduce their confusion limit. We found no significant detection of a diffuse radio continuum component. After a detailed discussion on the modelling of the cosmic-ray (CR) electron distribution and on the dSph magnetic properties, we present bounds on several physical quantities related to the dSphs, such that the total radio flux, the angular shape of the radio emissivity, the equipartition magnetic field, and the injection and equilibrium distributions of CR electrons. Finally, we discuss the connection to far-infrared and X-ray observations., Comment: 21 pages, 11 figure panels. Companion papers: arXiv:1407.5479 and arXiv:1407.4948. v3: minor revision, matches version accepted in MNRAS

This chapter shares the story of Ascension Health in order to offer an example of one company that has continuously integrated spirituality into its work and its workplaces successfully and with commitment. That story begins with religious sisters in the seventeenth-century France, follows the sisters to America in the nineteenth century, comes under our current name with the merging of two health Systems in 1999, and continues today with dedicated teams of lay and religious leading health-care ministry in more than 1,400 locations in 21 states and the District of Columbia under the Ascension Health banner. Our organization is the largest Catholic nonprofit health-care System in the United States, with more than 121,000 associates. Throughout the change and growth necessary for this trajectory, spirituality has undergirded both the proVision of healthcare and the commitment and care of associates.

Retinoic acid (RA) and thyroid hormone are critical for differentiation and organogenesis in the embryo. Mct8 (monocarboxylate transporter 8), expressed predominantly in the brain and placenta, mediates thyroid hormone uptake from the circulation and is required for normal neural development. RA induces differentiation of F9 mouse teratocarcinoma cells toward neurons as well as extraembryonal endoderm. We hypothesized that Mct8 is functionally expressed in F9 cells and induced by RA. All-trans-RA (tRA) and other RA receptor (RAR) agonists dramatically (>300-fold) induced Mct8. tRA treatment significantly increased uptake of triiodothyronine and thyroxine (4.1- and 4.3-fold, respectively), which was abolished by a selective Mct8 inhibitor, bromosulfophthalein. Sequence inspection of the Mct8 promoter region and 5′-rapid amplification of cDNA ends PCR analysis in F9 cells identified 11 transcription start sites and a proximal Sp1 site but no TATA box. tRA significantly enhanced Mct8 promoter activity through a consensus RA-responsive element located 6.6 kilobases upstream of the coding region. A chromatin immunoprecipitation assay demonstrated binding of RAR and retinoid X receptor to the RA response element. The promotion of thyroid hormone uptake through the transcriptional up-regulation of Mct8 by RAR is likely to be important for extraembryonic endoderm development and neural differentiation. This finding demonstrates cross-talk between RA signaling and thyroid hormone signaling in early development at the level of the thyroid hormone transporter.

The derivation of germ cells from human embryonic stem cells (hESCs) or human induced pluripotent stem (hIPS) cells represents a desirable experimental model and potential strategy for treating infertility. In the current study, we developed a triple biomarker assay for identifying and isolating human primordial germ cells (PGCs) by first evaluating human PGC formation during the first trimester in vivo. Next, we applied this technology to characterizing in vitro derived PGCs (iPGCs) from pluripotent cells. Our results show that codifferentiation of hESCs on human fetal gonadal stromal cells significantly improves the efficiency of generating iPGCs. Furthermore, the efficiency was comparable between various pluripotent cell lines regardless of origin from the inner cell mass of human blastocysts (hESCs), or reprogramming of human skin fibroblasts (hIPS). To better characterize the iPGCs, we performed Real-time polymerase chain reaction, microarray, and bisulfite sequencing. Our results show that iPGCs at day 7 of differentiation are transcriptionally distinct from the somatic cells, expressing genes associated with pluripotency and germ cell development while repressing genes associated with somatic differentiation (specifically multiple HOX genes). Using bisulfite sequencing, we show that iPGCs initiate imprint erasure from differentially methylated imprinted regions by day 7 of differentiation. However, iPGCs derived from hIPS cells do not initiate imprint erasure as efficiently. In conclusion, our results indicate that triple positive iPGCs derived from pluripotent cells differentiated on hFGS cells correspond to committed first trimester germ cells (before 9 weeks) that have initiated the process of imprint erasure. Disclosure of potential conflicts of interest is found at the end of this article.

Adult stem cells are set aside during development in order to provide a source for replenishment of tissue over time in response to damage or simply wear and tear. The literature suggests that stem cells can be found in most major organ systems, and that they possess defining characteristics, namely the ability to both self-renew and differentiate down one or more specific lineages. Many groups have sought to define stem cell specific physiology in a molecular fashion by identifying those genes specifically expressed in stem cells. Although these data suggest that there are genes frequently found to be upregulated in stem cells from various tissues, they do not definitively demonstrate that these cells all function similarly. There is also considerable data showing how various signaling pathways influence stem cell growth and differentiation. A review of this literature suggests that many of the well-described pathways affect adult mammalian stem cells from different tissues similarly, and that these effects are sometimes unique to stem cells as opposed to their progeny. In this review we summarize the effects of well-known signaling pathways on several of the most well defined stem cells and argue that the similarity with which unique stem cells from different tissues respond to external stimuli suggests that they share functional mechanisms.

We performed a deep search for radio synchrotron emissions induced by weakly interacting massive particles (WIMPs) annihilation or decay in six dwarf spheroidal (dSph) galaxies of the Local Group. Observations were conducted with the Australia Telescope Compact Array (ATCA) at 16 cm wavelength, with an rms sensitivity better than 0.05 mJy/beam in each field. In this work, we first discuss the uncertainties associated with the modeling of the expected signal, such as the shape of the dark matter (DM) profile and the dSph magnetic properties. We then investigate the possibility that point-sources detected in the proximity of the dSph optical center might be due to the emission from a DM cuspy profile. No evidence for an extended emission over a size of few arcmin (which is the DM halo size) has been detected. We present the associated bounds on the WIMP parameter space for different annihilation/decay final states and for different astrophysical assumptions. If the confinement of electrons and positrons in the dSph is such that the majority of their power is radiated within the dSph region, we obtain constraints on the WIMP annihilation rate which are well below the thermal value for masses up to few TeV. On the other hand, for conservative assumptions on the dSph magnetic properties, the bounds can be dramatically relaxed. We show however that, within the next 10 years and regardless of the astrophysical assumptions, it will be possible to progressively close in on the full parameter space of WIMPs by searching for radio signals in dSphs with SKA and its precursors., Comment: 17 pages, 6 figure panels. Companion papers: arXiv:1407.5479 and arXiv:1407.5482. v3: minor revision, matches published version

We present the science case and observations plan of the MeerKAT Fornax Survey, an HI and radio continuum survey of the Fornax galaxy cluster to be carried out with the SKA precursor MeerKAT. Fornax is the second most massive cluster within 20 Mpc and the largest nearby cluster in the southern hemisphere. Its low X-ray luminosity makes it representative of the environment where most galaxies live and where substantial galaxy evolution takes place. Fornax's ongoing growth makes it an excellent laboratory for studying the assembly of clusters, the physics of gas accretion and stripping in galaxies falling in the cluster, and the connection between these processes and the neutral medium in the cosmic web. We will observe a region of 12 deg$^2$ reaching a projected distance of 1.5 Mpc from the cluster centre. This will cover a wide range of environment density out to the outskirts of the cluster, where gas-rich in-falling groups are found. We will: study the HI morphology of resolved galaxies down to a column density of a few times 1e+19 cm$^{-2}$ at a resolution of 1 kpc; measure the slope of the HI mass function down to M(HI) 5e+5 M(sun); and attempt to detect HI in the cosmic web reaching a column density of 1e+18 cm$^{-2}$ at a resolution of 10 kpc., Comment: Proceedings of Science, "MeerKAT Science: On the Pathway to the SKA", Stellenbosch, 25-27 May 2016