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DNA methylation protects hematopoietic stem cell multipotency from myeloerythroid restriction

DNA methylation is a dynamic epigenetic mark that undergoes extensive changes during differentiation of self-renewing stem cells. However, whether these changes are the cause or consequence of stem cell fate remains unknown. Here, we show that alternative functional programs of hematopoietic stem cells (HSCs) are governed by gradual differences in methylation levels. Constitutive methylation is es

Niche recycling through division-independent egress of hematopoietic stem cells

Hematopoietic stem cells (HSCs) are thought to reside in discrete niches through stable adhesion, yet previous studies have suggested that host HSCs can be replaced by transplanted donor HSCs, even in the absence of cytoreductive conditioning. To explain this apparent paradox, we calculated, through cell surface phenotyping and transplantation of unfractionated blood, that similar to 1-5% of the t

Reactivity of phenyldi(2-thienyl) phosphine towards group 7 metal carbonyls: Carbon-phosphorus bond activation

Addition of phenyldi(2-thienyl) phosphine (PPhTh2) to [Re-2(CO)(10-n)(NCMe)(n)] (n = 1, 2) affords the substitution products [Re-2(CO)(10-n)(PhPTh2)(n)] (1, 2) together with small amounts of fac-[ClRe(CO)(3)(PPhTh2)(2)] (3) (n = 2). Reaction of [Re-2(CO)(10)] with PPhTh2 in refluxing xylene affords a mixture which includes 2, [Re-2(CO)(7)(PPhTh2)(mu-PPhTh)(mu-H)] (4), [Re-2(CO)(7)(PPhTh2)(mu-PPhTh

A Gradient-Enhanced Continuum Damage Model for Residually Stressed Fibre-Reinforced Materials at Finite Strains

The modelling of damage effects in materials constitutes a major challenge in various engineering-related disciplines. However, the assumption of purely local continuum damage formulations may lead to ill-posed boundary value problems and—with regard to numerical methods such as the finite element method—to mesh-dependent solutions, a vanishing localised damage zone upon mesh refinement, and hence

A toxicological and dermatological assessment of alkyl cyclic ketones when used as fragrance ingredients The RIFM Expert Panel

The alkyl cyclic ketone (ACK) fragrance ingredients are a diverse group of structures with Similar metabolic and toxicity profiles. ACK fragrance materials demonstrate low acute toxicity. Upon repeat dose testing, some adverse effects in biochemical and hematological parameters, and slightly increased liver and kidney weights were reported, primarily at high doses, resulting from adaptive effects.

Valence bond liquid phase in the honeycomb lattice material Li2RuO3

The honeycomb lattice material Li2RuO3 undergoes a dimerization of Ru4+ cations on cooling below 270 degrees C, where the magnetic susceptibility vanishes. We use density functional theory calculations to show that this reflects the formation of a valence bond crystal, with a strong structural bond disproportionation. On warming, x-ray diffraction shows that discrete threefold symmetry is regained

Hydrogen intercalation of graphene grown on 6H-SiC(0001)

Atomic hydrogen exposures on a monolayer graphene grown on the SiC(0001) surface are shown to result in hydrogen intercalation. The hydrogen intercalation induces a transformation of the monolayer graphene and the carbon buffer layer to bi-layer graphene without a buffer layer. The STM, LEED, and core-level photoelectron spectroscopy measurements reveal that hydrogen atoms can go underneath the gr

The State of Naming Conventions in R

Most programming language communities have naming conventions that are generally agreed upon, that is, a set of rules that governs how functions and variables are named. This is not the case with R, and a review of unofficial style guides and naming convention usage on CRAN shows that a number of different naming conventions are currently in use. Some naming conventions are, however, more popular

Phosphorus in soil treatment systems : accumulation and mobility

Septic tanks with subsequent soil treatment systems (STS) are a common treatment technique for domestic wastewater in rural areas. Phosphorus (P) leakage from such systems may pose a risk to water quality (especially if they are located relatively close to surface waters). In this study, six STS in Sweden (11-28 years old) were examined. Samples taken from the unsaturated subsoil beneath the distr

Prevalence and predictors of falls and dizziness in people younger and older than 80 years of age-A longitudinal cohort study.

The objectives were to investigate the prevalence and predictors for falls and dizziness among people younger and older than 80 years of age. The sample was drawn from the Swedish National study on Aging and Care (SNAC) and comprised 973 and 1273 subjects with data on the occurrence of falls and dizziness respectively at baseline. Follow-ups were made after 3- and 6-years. Data included socio-demo

A neural network clustering algorithm for the ATLAS silicon pixel detector

A novel technique to identify and split clusters created by multiple charged particles in the ATLAS pixel detector using a set of artificial neural networks is presented. Such merged clusters are a common feature of tracks originating from highly energetic objects, such as jets. Neural networks are trained using Monte Carlo samples produced with a detailed detector simulation. This technique repla

The Use of Central Nervous System Active Drugs During Pregnancy.

CNS-active drugs are used relatively often during pregnancy. Use during early pregnancy may increase the risk of a congenital malformation; use during the later part of pregnancy may be associated with preterm birth, intrauterine growth disturbances and neonatal morbidity. There is also a possibility that drug exposure can affect brain development with long-term neuropsychological harm as a result

Charge transport in InAs nanowire Josephson junctions

We present an extensive experimental and theoretical study of the proximity effect in InAs nanowires connected to superconducting electrodes. We fabricate and investigate devices with suspended gate-controlled nanowires and nonsuspended nanowires, with a broad range of lengths and normal-state resistances. We analyze the main features of the current-voltage characteristics: the Josephson current,

Linear Precoding for Broadcast Channels with Confidential Messages under Transmit-Side Channel Correlation

In this paper, we analyze the performance of regularized channel inversion (RCI) precoding in multiple-input single-output (MISO) broadcast channels with confidential messages under transmit-side channel correlation. We derive a deterministic equivalent for the achievable per-user secrecy rate which is almost surely exact as the number of transmit antennas and the number of users grow to infinity

Modelling the outdoor performance of wood products - A review on existing approaches

Service life planning and performance classification are key issues in the building sector. Well-functioning 'performance models' are absolutely essential to predict the service life and functionality of buildings, building assets, and building products overtime. Different types of performance models have been established for various building materials, but cannot necessarily transferred to wood-b

Growth of ectomycorrhizal fungi in drained peatland forests with variable P and K availability

The aim of this study was to investigate how the biomass of extramatrical mycorrhizal mycelia (EMM) is influenced by the addition of different phosphorus (P), potassium (K) and PK fertilizers in peatland forests with variable P and K availability. Four fertilizers were used: apatite, biotite, Rauta-PK (TM) (apatite and ferrosulphate) and a test fertilizer (50% apatite and 50% recycled iron phospha

Fitness cost of pheromone production in signaling female moths

A secondary sexual character may act as an honest signal of the quality of the individual if the trait bears a cost and if its expression is phenotypically condition dependent. The cost of increasing the trait should be tolerable for individuals in good condition but not for those in a poor condition. The trait thus provides an honest signal of quality that enables the receiver to choose higher qu

Canonical cerebellar graph wavelets and their application to fMRI activation mapping

Wavelet-based statistical parametric mapping (WSPM) is an extension of the classical approach in fMRI activation mapping that combines wavelet processing with voxel-wise statistical testing. We recently showed how WSPM, using graph wavelets tailored to the full gray-matter (GM) structure of each individual’s brain, can improve brain activity detection compared to using the classical wavelets that