Testing Quantum Gravity Induced Nonlocality via Optomechanical Quantum Oscillators

Several quantum gravity scenarios lead to physics below the Planck scale characterised by nonlocal, Lorentz invariant equations of motion. We show that such non-local effective field theories lead to a modified Schr\uf6dinger evolution in the nonrelativistic limit. In particular, the nonlocal evolution of opto-mechanical quantum oscillators is characterised by a spontaneous periodic squeezing that cannot be generated by environmental effects. We discuss constraints on the nonlocality obtained by past experiments, and show how future experiments (already under construction) will either see such effects or otherwise cast severe bounds on the non-locality scale (well beyond the current limits set by the Large Hadron Collider). This paves the way for table top, high precision experiments on massive quantum objects as a promising new avenue for testing some quantum gravity phenomenology

Agronomic and Environmental Benefits of Cover Crops in Northern Italy

Cover crops have a number of benefits (reduction of nitrate leaching and of soil erosion, control of weed seed bank, increase of soil organic matter and increase of cash crop yield), but these were seldom quantified in cropping systems of Northern Italy. This experiment aimed to quantify some of these effects, by comparing cover crop species and their management techniques

Penultimate deglacial warming across the Mediterranean Sea revealed by clumped isotopes in foraminifera

The variability of seawater temperature through time is a critical measure of climate change, yet its reconstruction remains problematic in many regions. Mg/Ca and oxygen isotope (δ18OC) measurements in foraminiferal carbonate shells can be combined to reconstruct seawater temperature and δ18O (δ18OSW). The latter is a measure of changes in local hydrology (e.g., precipitation/evaporation, freshwater inputs) and global ice volume. But diagenetic processes may affect foraminiferal Mg/Ca. This restricts its potential in many places, including the Mediterranean Sea, a strategic region for deciphering global climate and sea-level changes. High alkalinity/salinity conditions especially bias Mg/Ca temperatures in the eastern Mediterranean (eMed). Here we advance the understanding of both western Mediterranean (wMed) and eMed hydrographic variability through the penultimate glacial termination (TII) and last interglacial, by applying the clumped isotope (Δ47) paleothermometer to planktic foraminifera with a novel data-processing approach. Results suggest that North Atlantic cooling during Heinrich stadial 11 (HS11) affected surface-water temperatures much more in the wMed (during winter/spring) than in the eMed (during summer). The method’s paired Δ47 and δ18OC data also portray δ18OSW. These records reveal a clear HS11 freshwater signal, which attenuated toward the eMed, and also that last interglacial surface warming in the eMed was strongly amplified by water-column stratification during the deposition of the organic-rich (sapropel) interval known as S5

Dopamine neuronal loss contributes to memory and reward dysfunction in a model of Alzheimer's disease

Alterations of the dopaminergic (DAergic) system are frequently reported in Alzheimer’s disease (AD) patients and are commonly linked to cognitive and non-cognitive symptoms. However, the cause of DAergic system dysfunction in AD remains to be elucidated. We investigated alterations of the midbrain DAergic system in the Tg2576 mouse model of AD, overexpressing a mutated human amyloid precursor protein (APPswe). Here, we found an age-dependent DAergic neuron loss in the ventral tegmental area (VTA) at pre-plaque stages, although substantia nigra pars compacta (SNpc) DAergic neurons were intact. The selective VTA DAergic neuron degeneration results in lower DA outflow in the hippocampus and nucleus accumbens (NAc) shell. The progression of DAergic cell death correlates with impairments in CA1 synaptic plasticity, memory performance and food reward processing. We conclude that in this mouse model of AD, degeneration of VTA DAergic neurons at pre-plaque stages contributes to memory deficits and dysfunction of reward processing

A 4-Selenocysteine, 2-Selenocysteine Insertion Sequence (SECIS) Element Methionine Sulfoxide Reductase from \u3ci\u3eMetridium senile\u3c/i\u3e Reveals a Non-catalytic Function of Selenocysteines

Selenocysteine (Sec) residues occur in thiol oxidoreductase families, and functionally characterized selenoenzymes typically have a single Sec residue used directly for redox catalysis. However, how new Sec residues evolve and whether non-catalytic Sec residues exist in proteins is not known. Here, we computationally identified several genes with multiple Sec insertion sequence (SECIS) elements, one of which was a methionine-Rsulfoxide reductase (MsrB) homolog from Metridium senile that has four in-frame UGA codons and two nearly identical SECIS elements. One of the UGA codons corresponded to the conserved catalytic Sec or Cys in MsrBs, whereas the three other UGA codons evolved recently and had no homologs with Sec or Cys in these positions. Metabolic 75Se labeling showed that all four in-frame UGA codons supported Sec insertion and that both SECIS elements were functional and collaborated in Sec insertion at each UGA codon. Interestingly, recombinant M. senile MsrB bound iron, and further analyses suggested the possibility of binding an iron-sulfur cluster by the protein. These data show that Sec residues may appear transiently in genes containing SECIS elements and be adapted for non-catalytic functions

Resolving the age bimodality of galaxy stellar populations on kpc scales

Galaxies in the local Universe are known to follow bimodal distributions in the global stellar populations properties. We analyze the distribution of the local average stellar-population ages of 654,053 sub-galactic regions resolved on ~1-kpc scales in a volume-corrected sample of 394 galaxies, drawn from the CALIFA-DR3 integral-field-spectroscopy survey and complemented by SDSS imaging. We find a bimodal local-age distribution, with an old and a young peak primarily due to regions in early-type galaxies and star-forming regions of spirals, respectively. Within spiral galaxies, the older ages of bulges and inter-arm regions relative to spiral arms support an internal age bimodality. Although regions of higher stellar-mass surface-density, mu*, are typically older, mu* alone does not determine the stellar population age and a bimodal distribution is found at any fixed mu*. We identify an "old ridge" of regions of age ~9 Gyr, independent of mu*, and a "young sequence" of regions with age increasing with mu* from 1-1.5 Gyr to 4-5 Gyr. We interpret the former as regions containing only old stars, and the latter as regions where the relative contamination of old stellar populations by young stars decreases as mu* increases. The reason why this bimodal age distribution is not inconsistent with the unimodal shape of the cosmic-averaged star-formation history is that i) the dominating contribution by young stars biases the age low with respect to the average epoch of star formation, and ii) the use of a single average age per region is unable to represent the full time-extent of the star-formation history of "young-sequence" regions.Comment: 17 pages, 11 figures, MNRAS accepte

High resolution computed tomography quantitation of emphysema is correlated with selected lung function values in stable COPD.

BACKGROUND: The literature shows conflicting results when high-resolution computed tomography (HRCT) scores of emphysema were correlated with different indices of airflow obstruction. OBJECTIVES: We correlated HRCT scores of emphysema with different indices of airflow obstruction. METHODS: We performed HRCT of the chest in 59 patients, all smokers or ex-smokers, with stable chronic obstructive pulmonary disease of different severity [GOLD stages I-IV; mean age \ub1 SD 67.8 \ub1 7.3 years; pack/years 51.0 \ub1 34.6; percent predicted forced expiratory volume in 1 s (FEV(1)% predicted) 52.3 \ub1 17.6; post-bronchodilator FEV(1)% predicted 56.5 \ub1 19.1; FEV(1)/forced vital capacity (FVC) ratio 50.8 \ub1 10.2; post-bronchodilator FEV(1)/FVC ratio 51.6 \ub1 11.0; percent diffusion lung capacity for carbon monoxide (DLCO%) 59.2 \ub1 21.1; DLCO/percent alveolar volume (VA%) 54.5 \ub1 18.2; percent residual volume 163.0 \ub1 35.6; percent total lung capacity (TLC%) 113.2 \ub1 15; residual volume/TLC 1.44 \ub1 0.2]. All patients were in stable phase. RESULTS: The mean \ub1 SD visual emphysema score in all patients was 25.6 \ub1 25.4%. There was a weak but significant correlation between the percentage of pulmonary emphysema and numbers of pack/years (R = +0.31, p = 0.024). The percentage of emphysema was inversely correlated with the FEV(1)/FVC ratio before and after bronchodilator use (R = -0.44, p = 0.002, and R = -0.39, p = 0.005), DLCO% (R = -0.64, p = 0.0003) and DLCO/VA% (R = -0.68, p < 0.0001). A weak positive correlation was also found with TLC% (R = +0.28, p = 0.048). When patients with documented emphysema were considered separately, the best significant correlation observed was between DLCO/VA% and HRCT scan score (p = 0.007). CONCLUSIONS: These data suggest that in patients with stable chronic obstructive pulmonary disease of varying severity, the presence of pulmonary emphysema is best represented by the impaired gas exchange capability of the respiratory system

Short-term multidisciplinary non-pharmacological intervention is effective in reducing liver fat content assessed non-invasively in patients with nonalcoholic fatty liver disease (NAFLD)

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Treatment of recurrent genotype 4 hepatitis C after liver transplantation: early virological response is predictive of sustained virological response. An AISF RECOLT-C group study

Introduction. Hepatitis C virus genotype 4 is predominant in the Middle East and Northern Africa, even if it has recently spread to Southern Europe. Data about the treatment of post-liver transplantation (LT) genotype 4 hepatitis C recurrence are scarce. We report a retrospective analysis of post-LT genotype 4 hepatitis C treatment in 9 Italian transplant centres, focusing on the overall survival rates and treatment outcome. Results. Among 452 recipients, we identified 17 HCV genotype 4 patients (16 males, 1 female) transplanted between 1998 and 2007. All patients received combined antiviral treatment with conventional doses of interferon (recombinant or pegylated) and ribavirin after histological diagnosis of hepatitis C recurrence. The observed overall survival after LT was 100% at 1 year and 83.3% at 5 years. More than 1/3 (35.3%) of patients achieved a sustained virological response (SVR) and 40% (data available in 15 subjects) an early virological response (EVR), which was significantly associated with the achievement of SVR (overall accuracy: 85.7%; predictive values of EVR absence/presence 80/88.8%; chi-square p < 0.05). Conclusion. In conclusion, in post-LT genotype 4 hepatitis C treatment, SVR rates are similar to genotype 1. Patients who don't show an EVR are not likely to achieve a SVR