Derivation of embryonic stem (ES) cells genetically identical to a patient by somatic cell nuclear transfer (SCNT) holds the potential to cure or alleviate the symptoms of many degenerative diseases ...while circumventing concerns regarding rejection by the host immune system. However, the concept has only been achieved in the mouse, whereas inefficient reprogramming and poor embryonic development characterizes the results obtained in primates. Here, we used a modified SCNT approach to produce rhesus macaque blastocysts from adult skin fibroblasts, and successfully isolated two ES cell lines from these embryos. DNA analysis confirmed that nuclear DNA was identical to donor somatic cells and that mitochondrial DNA originated from oocytes. Both cell lines exhibited normal ES cell morphology, expressed key stem-cell markers, were transcriptionally similar to control ES cells and differentiated into multiple cell types in vitro and in vivo. Our results represent successful nuclear reprogramming of adult somatic cells into pluripotent ES cells and demonstrate proof-of-concept for therapeutic cloning in primates.
We present a measurement of the volumetric rate of superluminous supernovae (SLSNe) at z ~ 1.0, measured using archival data from the first four years of the Canada-France-Hawaii Telescope Supernova ...Legacy Survey (SNLS). We develop a method for the photometric classification of SLSNe to construct our sample. Our sample includes two previously spectroscopically identified objects, and a further new candidate selected using our classification technique. We use the point-source recovery efficiencies from Perrett et al. and a Monte Carlo approach to calculate the rate based on our SLSN sample. We find that the three identified SLSNe from SNLS give a rate of 91... SNe yr super( -1) Gpc super( -3) at a volume-weighted redshift of z = 1.13. This is equivalent to 2.2...x10 super( -4) of the volumetric core-collapse supernova rate at the same redshift. When combined with other rate measurements from the literature, we show that the rate of SLSNe increases with redshift in a manner consistent with that of the cosmic star formation history. We also estimate the rate of ultra-long gamma-ray bursts based on the events discovered by the Swift satellite, and show that it is comparable to the rate of SLSNe, providing further evidence of a possible connection between these two classes of events. We also examine the host galaxies of the SLSNe discovered in SNLS, and find them to be consistent with the stellar-mass distribution of other published samples of SLSNe. (ProQuest: ... denotes formulae/symbols omitted.)
To examine whether serum cytokines and spontaneous production of peripheral blood mononuclear cell (PBMC) cytokines are associated with the risk of incident Alzheimer disease (AD).
We followed 691 ...cognitively intact community-dwelling participants (mean age 79 years, 62% women) and related PBMC cytokine production (tertiles of spontaneous production of interleukin 1 IL-1, IL-1 receptor antagonist, and tumor necrosis factor alpha TNF-alpha) and serum C-reactive protein and interleukin 6 (IL-6) to the risk of incident AD.
Adjusting for clinical covariates, individuals in the top two tertiles (T2 and T3) of PBMC production of IL-1 or the top tertile (T3) of PBMC production of TNF-alpha were at increased risk of developing AD (multivariable-adjusted hazard ratio HR for IL-1 T2 = 2.84, 95% CI 1.09 to 7.43; p = 0.03 and T3 = 2.61, 95% CI 0.96 to 7.07; p = 0.06; for TNF-alpha, adjusted HR for T2 = 1.30, 95% CI 0.53 to 3.17; p = 0.57 and T3 = 2.59, 95% CI 1.09 to 6.12; p = 0.031) compared with those in the lowest tertile (T1).
Higher spontaneous production of interleukin 1 or tumor necrosis factor alpha by peripheral blood mononuclear cells may be a marker of future risk of Alzheimer disease (AD) in older individuals. These data strengthen the evidence for a pathophysiologic role of inflammation in the development of clinical AD.
Aims.
We look to provide a detailed description of the SPectroscopic IDentification of ERosita Sources (SPIDERS) survey, an SDSS-IV programme aimed at obtaining spectroscopic classification and ...redshift measurements for complete samples of sufficiently bright X-ray sources.
Methods.
We describe the SPIDERS X-ray Point Source Spectroscopic Catalogue, considering its store of 11 092 observed spectra drawn from a parent sample of 14 759 ROSAT and XMM sources over an area of 5129 deg
2
covered in SDSS-IV by the eBOSS survey.
Results.
This programme represents the largest systematic spectroscopic observation of an X-ray selected sample. A total of 10 970 (98.9%) of the observed objects are classified and 10 849 (97.8%) have secure redshifts. The majority of the spectra (10 070 objects) are active galactic nuclei (AGN), 522 are cluster galaxies, and 294 are stars.
Conclusions.
The observed AGN redshift distribution is in good agreement with simulations based on empirical models for AGN activation and duty cycle. Forming composite spectra of type 1 AGN as a function of the mass and accretion rate of their black holes reveals systematic differences in the H-beta emission line profiles. This study paves the way for systematic spectroscopic observations of sources that are potentially to be discovered in the upcoming eROSITA survey over a large section of the sky.
The conversion of light into usable chemical and mechanical energy is pivotal to several biological and chemical processes, many of which occur in solution. To understand the structure–function ...relationships mediating these processes, a technique with high spatial and temporal resolutions is required. Here, we report on the design and commissioning of a liquid-phase mega-electron-volt (MeV) ultrafast electron diffraction instrument for the study of structural dynamics in solution. Limitations posed by the shallow penetration depth of electrons and the resulting information loss due to multiple scattering and the technical challenge of delivering liquids to vacuum were overcome through the use of MeV electrons and a gas-accelerated thin liquid sheet jet. To demonstrate the capabilities of this instrument, the structure of water and its network were resolved up to the
3
rd hydration shell with a spatial resolution of 0.6 Å; preliminary time-resolved experiments demonstrated a temporal resolution of 200 fs.
We report on the X-ray evolution over the last sim9 Gyr of cosmic history (i.e., since image) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South ...(CDF-N and E-CDF-S, respectively; jointly CDFs) survey fields. Our late-type galaxy sample consists of 2568 galaxies, which were identified using rest-frame optical colors and HST morphologies. We utilized X-ray stacking analyses to investigate the X-ray emission from these galaxies, emphasizing the contributions from normal galaxies that are not dominated by active galactic nuclei (AGNs). Over this redshift range, we find significant increases (factors of sim5-10) in the X-ray-to-optical mean luminosity ratio (image /image) and the X-ray-to-stellar mass mean ratio (image /image) for galaxy populations selected by image and image, respectively. When analyzing galaxy samples selected via SFR, we find that the mean X-ray-to-SFR ratio (image /SFR) is consistent with being constant over the entire redshift range for galaxies with SFR = 1-100 image yrimage, thus demonstrating that X-ray emission can be used as a robust indicator of star formation activity out to image. We find that the star formation activity (as traced by X-ray luminosity) per unit stellar mass in a given redshift bin increases with decreasing stellar mass over the redshift range z = 0.2-1, which is consistent with previous studies of how star formation activity depends on stellar mass. Finally, we extend our X-ray analyses to Lyman break galaxies at image and estimate that image /image at image is similar to its value at image.
The DEEP2 and COMBO-17 surveys are compared to study luminosity functions of red and blue galaxies to z similar to 1. The two surveys have different methods and sensitivities, but nevertheless ...results agree. After z similar to 1, M* sub(B) has dimmed by 1.2-1.3 mag for all colors of galaxies, phi * for blue galaxies has hardly changed, and phi * for red galaxies has at least doubled (our formal value is similar to 0.5 dex). Luminosity density J sub(B) has fallen by 0.6 dex for blue galaxies but has remained nearly constant for red galaxies. These results imply that the number and total stellar mass of blue galaxies have been substantially constant since z similar to 1, whereas those of red galaxies (near L*) have been significantly rising. To explain the new red galaxies, a "mixed" scenario is proposed in which star formation in blue cloud galaxies is quenched, causing them to migrate to the red sequence, where they merge further in a small number of stellar mergers. This mixed scenario matches the local boxy-disky transition for nearby ellipticals, as well as red sequence stellar population scaling laws such as the color-magnitude and Mg- sigma relations (which are explained as fossil relics from blue progenitors). Blue galaxies enter the red sequence via different quenching modes, each of which peaks at a different characteristic mass and time. The red sequence therefore likely builds up in different ways at different times and masses, and the concept of a single process that is "downsizing" (or upsizlng) probably does not apply. Our claim in this paper of a rise in the number of red galaxies applies to galaxies near L*. Accurate counts of brighter galaxies on the steep part of the Schechter function require more accurate photometry than is currently available.
Objectives To relate cancer since entry into the Framingham Heart Study with the risk of incident Alzheimer’s disease and to estimate the risk of incident cancer among participants with and without ...Alzheimer’s disease.Design Community based prospective cohort study; nested age and sex matched case-control study. Setting Framingham Heart Study, USA.Participants 1278 participants with and without a history of cancer who were aged 65 or more and free of dementia at baseline (1986-90). Main outcome measures Hazard ratios and 95% confidence intervals for the risks of Alzheimer’s disease and cancer.Results Over a mean follow-up of 10 years, 221 cases of probable Alzheimer’s disease were diagnosed. Cancer survivors had a lower risk of probable Alzheimer’s disease (hazard ratio 0.67, 95% confidence interval 0.47 to 0.97), adjusted for age, sex, and smoking. The risk was lower among survivors of smoking related cancers (0.26, 0.08 to 0.82) than among survivors of non-smoking related cancers (0.82, 0.57 to 1.19). In contrast with their decreased risk of Alzheimer’s disease, survivors of smoking related cancer had a substantially increased risk of stroke (2.18, 1.29 to 3.68). In the nested case-control analysis, participants with probable Alzheimer’s disease had a lower risk of subsequent cancer (0.39, 0.26 to 0.58) than reference participants, as did participants with any Alzheimer’s disease (0.38) and any dementia (0.44).Conclusions Cancer survivors had a lower risk of Alzheimer’s disease than those without cancer, and patients with Alzheimer’s disease had a lower risk of incident cancer. The risk of Alzheimer’s disease was lowest in survivors of smoking related cancers, and was not primarily explained by survival bias. This pattern for cancer is similar to that seen in Parkinson’s disease and suggests an inverse association between cancer and neurodegeneration.
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