The Carboniferous carbon isotope record from sedimentary organic matter: can we disentangle the carbon cycle?

A comprehensive analysis of the 13C composition of sedimentary organic matter from Euramerican Carboniferous successions indicates there are significant shifts in 13C through this key time interval. Our studies have revealed that, at an individual location, the source and delivery mechanism of the sediment contribute to the type of organic matter preserved and, in turn this influences the measured 13C values from bulk sedimentary organic matter of organic matter

Vitamin D deficiency in traumatic brain injury and its relationship with severity of injury and quality of life: a prospective, observational study

This single-centre prospective observational study aims to describe the prevalence of vitamin D deficiency (VDD) in the traumatic brain injury (TBI) population and identify any relationship between vitamin D and severity of head injury or quality of life. 124 TBI patients had serum vitamin D (25-OHD) levels measured at the local post-TBI endocrine screening clinic over 20 months. Quality of Life after Brain Injury (QOLIBRI) questionnaires were completed by the patient concurrently. A multivariate regressional analysis was performed, controlling for age, season, ethnicity, time since injury, TBI severity and gender. 34% (n=42) of the cohort were vitamin D deficient (25-OHD <25nmol/L) with a further 23% (n=29) having insufficient levels (25-OHD 25-50nmol/L). Vitamin D was significantly lower in severe TBI compared to mild TBI (n=95, p=0.03, CI 95% -23.60 to -1.21, mean effect size 12.40 nmol/L). There was a trend for self-reported quality of life to be better in patients with optimum vitamin D levels compared to patients with deficient vitamin D levels, controlling for severity of injury (n=81, p=0.05, CI 95% -0.07 to 21.27). This is the first study to identify a significant relationship between vitamin D levels and severity of head injury. Clinicians should actively screen for and treat VDD in head injured patients to reduce the risk of further morbidity such as osteomalacia and cardiovascular disease. Future research should establish the natural history of vitamin D levels following TBI to identify at which stage VDD develops and whether vitamin D replacement could have a beneficial effect on recovery and quality of life

Cytochrome oxidase subunit VI of Trypanosoma brucei is imported without a cleaved presequence and is developmentally regulated at both RNA and protein levels

Mitochondrial respiration in the African trypanosome undergoes dramatic developmental stage regulation. This requires co-ordinated control of components encoded by both the nuclear genome and the kinetoplast, the unusual mitochondrial genome of these parasites. As a model for understanding the co-ordination of these genomes, we have examined the regulation and mitochondrial import of a nuclear-encoded component of the cytochrome oxidase complex, cytochrome oxidase subunit VI (COXVI). By generating transgenic trypanosomes expressing intact or mutant forms of this protein, we demonstrate that COXVI is not imported using a conventional cleaved presequence and show that sequences at the N-terminus of the protein are necessary for correct mitochondrial sorting. Analyses of endogenous and transgenic COXVI mRNA and protein expression in parasites undergoing developmental stage differentiation demonstrates a temporal order of control involving regulation in the abundance of, first, mRNA and then protein. This represents the first dissection of the regulation and import of a nuclear-encoded protein into the cytochrome oxidase complex in these organisms, which were among the earliest eukaryotes to possess a mitochondrion

Quantum information processing with superconducting qubits in a microwave field

We investigate the quantum dynamics of a Cooper-pair box with a superconducting loop in the presence of a nonclassical microwave field. We demonstrate the existence of Rabi oscillations for both single- and multi-photon processes and, moreover, we propose a new quantum computing scheme (including one-bit and conditional two-bit gates) based on Josephson qubits coupled through microwaves.Comment: 7 pages, 1 figur

The Future Landscape of High-Redshift Galaxy Cluster Science

Large scale structure and cosmolog

Iodide organification defect in a cold thyroid nodule: Absence of iodide effect on cyclic AMP accumulation

A follicular adenoma of the thyroid was ‘hot’ one hour after 99mTc pertechnetate administration, but ‘cold’24 h after 131I iodide administration. Incubation of the tissue in vitro demonstrated a defect in iodide binding to proteins that was abolished by addition of an H2O2 generating system. In this tissue iodide failed to inhibit TSH-induced cyclic AMP accumulation. The results show that iodide oxidation is required for its inhibitory action on cyclic AMP accumulation in human thyroid.SCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe