Milling plant and soil material in plastic tubes over-estimates carbon and under-estimates nitrogen concentrations

Peer reviewedPostprin

Histone deacetylase (HDAC) 1 and 2 complexes regulate both histone acetylation and crotonylation in vivo.

Proteomic analysis of histones has shown that they are subject to a superabundance of acylations, which extend far beyond acetylation, to include: crotonylation, propionylation, butyrylation, malonylation, succinylation, β-hydroxybutyrylation and 2-hydroxyisobutyrylation. To date, much of the functional data has focussed on histone crotonylation which, similar to acetylation, has been associated with positive gene regulation and is added by the acyltransferase, p300. Although Sirtuins 1-3, along with HDAC3, have been shown to possess decrotonylase activity in vitro, there is relatively little known about the regulation of histone crotonylation in vivo. Here we show that Histone Deacetylase 1 and 2 (HDAC1/2), the catalytic core of numerous co-repressor complexes, are important histone decrotonylase enzymes. A ternary complex of HDAC1/CoREST1/LSD1 is able to hydrolyse both histone H3 Lys18-acetyl (H3K18ac) and H3 Lys18-crotonyl (H3K18cr) peptide substrates. Genetic deletion of HDAC1/2 in ES cells increases global levels of histone crotonylation and causes an 85% reduction in total decrotonylase activity. Furthermore, we mapped H3K18cr in cells using ChIP-seq, with and without HDAC1/2, and observed increased levels of crotonylation, which largely overlaps with H3K18ac in the vicinity of transcriptional start sites. Collectively, our data indicate that HDAC1/2 containing complexes are critical regulators of histone crotonylation in vivo

Effects of beta-alanine supplementation on brain homocarnosine/carnosine signal and cognitive function: an exploratory study

Objectives: Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2). Methods: In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen trained male cyclists completed four 20-Km cycling time trials (two pre supplementation and two post supplementation), with a battery of cognitive function tests (Stroop test, Sternberg paradigm, Rapid Visual Information Processing task) being performed before and after exercise on each occasion. Results: In Study 1, there were no within-group effects of beta-alanine supplementation on brain homocarnosine/carnosine signal in either vegetarians (p = 0.99) or omnivores (p = 0.27); nor was there any effect when data from both groups were pooled (p = 0.19). Similarly, there was no group by time interaction for brain homocarnosine/carnosine signal (p = 0.27). In study 2, exercise improved cognitive function across all tests (P0.05) of beta-alanine supplementation on response times or accuracy for the Stroop test, Sternberg paradigm or RVIP task at rest or after exercise. Conclusion: 28 d of beta-alanine supplementation at 6.4g d-1 appeared not to influence brain homocarnosine/ carnosine signal in either omnivores or vegetarians; nor did it influence cognitive function before or after exercise in trained cyclists

Constraints on Nucleon Decay via "Invisible" Modes from the Sudbury Neutrino Observatory

Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to ``invisible'' modes, such as n -> 3 nu. The analysis was based on a search for gamma-rays from the de-excitation of the residual nucleus that would result from the disappearance of either a proton or neutron from O16. A limit of tau_inv > 2 x 10^{29} years is obtained at 90% confidence for either neutron or proton decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton decay modes and 400 times more stringent than similar neutron modes.Comment: Update includes missing efficiency factor (limits change by factor of 2) Submitted to Physical Review Letter

The utility of the Historical Clinical Risk -20 Scale as a predictor of outcomes in decisions to transfer patients from high to lower levels of security-A UK perspective

<p>Abstract</p> <p>Background</p> <p>Structured Professional Judgment (SPJ) approaches to violence risk assessment are increasingly being adopted into clinical practice in international forensic settings. The aim of this study was to examine the predictive validity of the Historical Clinical Risk -20 (HCR-20) violence risk assessment scale for outcome following transfers from high to medium security in a United Kingdom setting.</p> <p>Methods</p> <p>The sample was predominately male and mentally ill and the majority of cases were detained under the criminal section of the Mental Health Act (1986). The HCR-20 was rated based on detailed case file information on 72 cases transferred from high to medium security. Outcomes were examined, independent of risk score, and cases were classed as "success or failure" based on established criteria.</p> <p>Results</p> <p>The mean length of follow up was 6 years. The total HCR-20 score was a robust predictor of failure at lower levels of security and return to high security. The Clinical and Risk management items contributed most to predictive accuracy.</p> <p>Conclusions</p> <p>Although the HCR-20 was designed as a violence risk prediction tool our findings suggest it has potential utility in decisions to transfer patients from high to lower levels of security.</p

Pathways for outpatient management of venous thromboembolism in a UK centre.

It has become widely recognised that outpatient treatment may be suitable for many patients with venous thromboembolism. In addition, non-vitamin K antagonist oral anticoagulants that have been approved over the last few years have the potential to be an integral component of the outpatient care pathway, owing to their oral route of administration, lack of requirement for routine anticoagulation monitoring and simple dosing regimens. A robust pathway for outpatient care is also vital; one such pathway has been developed at Sheffield Teaching Hospitals in the UK. This paper describes the pathway and the arguments in its favour as an example of best practice and value offered to patients with venous thromboembolism. The pathway has two branches (one for deep vein thrombosis and one for pulmonary embolism), each with the same five-step process for outpatient treatment. Both begin from the point that the patient presents (in the Emergency Department, Thrombosis Clinic or general practitioner's office), followed by diagnosis, risk stratification, treatment choice and, finally, follow-up. The advantages of these pathways are that they offer clear, evidence-based guidance for the identification, diagnosis and treatment of patients who can safely be treated in the outpatient setting, and provide a detailed, stepwise process that can be easily adapted to suit the needs of other institutions. The approach is likely to result in both healthcare and economic benefits, including increased patient satisfaction and shorter hospital stays

Vigorous lateral export of the meltwater outflow from beneath an Antarctic ice shelf

The instability and accelerated melting of the Antarctic Ice Sheet are among the foremost elements of contemporary global climate change1, 2. The increased freshwater output from Antarctica is important in determining sea level rise1, the fate of Antarctic sea ice and its effect on the Earth’s albedo4, 5, ongoing changes in global deep-ocean ventilation6, and the evolution of Southern Ocean ecosystems and carbon cycling7, 8. A key uncertainty in assessing and predicting the impacts of Antarctic Ice Sheet melting concerns the vertical distribution of the exported meltwater. This is usually represented by climate-scale models3–5, 9 as a near-surface freshwater input to the ocean, yet measurements around Antarctica reveal the meltwater to be concentrated at deeper levels10, 11, 12, 13, 14. Here we use observations of the turbulent properties of the meltwater outflows from beneath a rapidly melting Antarctic ice shelf to identify the mechanism responsible for the depth of the meltwater. We show that the initial ascent of the meltwater outflow from the ice shelf cavity triggers a centrifugal overturning instability that grows by extracting kinetic energy from the lateral shear of the background oceanic flow. The instability promotes vigorous lateral export, rapid dilution by turbulent mixing, and finally settling of meltwater at depth. We use an idealized ocean circulation model to show that this mechanism is relevant to a broad spectrum of Antarctic ice shelves. Our findings demonstrate that the mechanism producing meltwater at depth is a dynamically robust feature of Antarctic melting that should be incorporated into climate-scale models