Decay and Decoupling of heavy Right-handed Majorana Neutrinos in the L-R model

Heavy right-handed neutrinos are of current interest. The interactions and decay of such neutrinos determine their decoupling epoch during the evolution of the universe. This in turn affects various observable features like the energy density, nucleosynthesis, CMBR spectrum, galaxy formation, and baryogenesis. Here, we consider reduction of right-handed electron-type Majorana neutrinos, in the left-right symmetric model, by the WR+ - WR- channel and the channel originating from an anomaly, involving the SU(2)R gauge group, as well as decay of such neutrinos. We study the reduction of these neutrinos for different ranges of left-right model parameters, and find that, if the neutrino mass exceeds the right-handed gauge boson mass, then the neutrinos never decouple for realistic values of the parameters, but, rather, decay in equilibrium. Because there is no out-of-equilibrium decay, no mass bounds can be set for the neutrinos.Comment: Latex, 16 pages, No figures. Some additions in the text and references. Conclusions unaffected. To appear in Eur. Phys. J.

The role of soils in delivering Nature's Contributions to People

Data accessibility. This article does not contain any additional data. Funding Information:The input of P.S. contributes to Soils-R-GRREAT (NE/ P019455/1) and the input of P.S. and S.D.K. contributes to the European Union’s Horizon 2020 Research and Innovation Programme through project CIRCASA (grant agreement no. 774378). Acknowledgements. T.K.A. acknowledges the support of ‘Towards Integrated Nitrogen Management System (INMS)’ funded by the Global Environment Facility (GEF), executed through the UK’s Natural Environment Research Council (NERC).Peer reviewedPostprin

Measurement of D-0, D+, D+* and D-s(+) production in pp collisions at root s=5.02 TeV with ALICE

The measurements of the production of prompt D0, D+, D+, and Ds+ mesons in proton-proton (pp) collisions at TeV with the ALICE detector at the Large Hadron Collider (LHC) are reported. D mesons were reconstructed at mid-rapidity (|y|<0.5) via their hadronic decay channels D0K-+, D+K-++, D+D0+K-++, Ds+phi+K+K-+, and their charge conjugates. The production cross sections were measured in the transverse momentum interval 0<36 for D0, 1<36 for D+ and D+, and in 2<24 for Ds+ mesons. Thanks to the higher integrated luminosity, an analysis in finer pT bins with respect to the previous measurements at sTeV was performed, allowing for a more detailed description of the cross-section pT shape. The measured pT-differential production cross sections are compared to the results at s=7TeV and to four different perturbative QCD calculations. Its rapidity dependence is also tested combining the ALICE and LHCb measurements in pp collisions at s=5.02 TeV. This measurement will allow for a more accurate determination of the nuclear modification factor in p-Pb and Pb-Pb collisions performed at the same nucleon-nucleon centre-of-mass energy

Understanding the role of steroids in typical and atypical brain development: Advantages of using a "brain in a dish" approach.

Steroids have an important role in growth, development, sexual differentiation and reproduction. All four classes of steroids, androgens, oestrogens, progestogens and glucocorticoids, have varying effects on the brain. Androgens and oestrogens are involved in the sexual differentiation of the brain, and also influence cognition. Progestogens such as progesterone and its metabolites have been shown to be involved in neuroprotection, although their protective effects are timing-dependent. Glucocorticoids are linked with stress and memory performance, also in a dose- and time-dependent manner. Importantly, dysfunction in steroid function has been implicated in the pathogenesis of disease. Moreover, regulating steroid-signalling has been suggested as potential therapeutic avenue for the treatment of a number of neurodevelopmental, psychiatric and neurodegenerative disorders. Therefore, clarifying the role of steroids in typical and atypical brain function is essential for understanding typical brain functions, as well as determining their potential use for pharmacological intervention in the atypical brain. However, the majority of studies have thus far have been conducted using animal models, with limited work using native human tissue or cells. Here, we review the effect of steroids in the typical and atypical brain, focusing on the cellular, molecular functions of these molecules determined from animal models, and the therapeutic potential as highlighted by human studies. We further discuss the promise of human-induced pluripotent stem cells, including advantages of using three-dimensional neuronal cultures (organoids) in high-throughput screens, in accelerating our understanding of the role of steroids in the typical brain, and also with respect to their therapeutic value in the understanding and treatment of the atypical brain

Synthetic Nitrogen Fertiliser in South Asia: Production, Import, Export, and Use for Crops, South Asia Nitrogen Hub (SANH) Policy Brief

This policy brief is produced by the UKRI GCRF South Asian Nitrogen Hub (SANH). It provides an overview of the patterns and trends in synthetic nitrogen (N) fertiliser use in crop production, import, export and emission in the South Asian Region (SAR) and its member countries; Afghanistan, Bangladesh, Bhutan, Nepal, India, Maldives, Pakistan, and Sri Lanka. In summary, reactive nitrogen (Nr) in fertilisers is essential for meeting global food and animal feed demands, but Nr pollution has become a major environmental issue across all scales. For SAR, inefficient use of synthetic N fertiliser is a key factor contributing to water pollution, air pollution, climate change, biodiversity loss and soil degradation. Further insights are provided on major fertiliser products, as well as in crop production, import and export. These data are essential for informing and promoting sustainable nitrogen management. Evidence based policy is more important than ever. The SANH is supported by UK Research and Innovation (UKRI) through its Global Challenge Research Fund (GCRF) to gather evidence on nitrogen issues to support countries in the South Asian Region (SAR) comprising eight countries (Nepal, Bangladesh, Pakistan, India, Bhutan, Sri Lanka, Afghanistan, and Maldives) to identify solutions and reduce nitrogen waste. SANH is pioneering a UK-SAR research partnership to catalyse transformational change in SAR to tackle the nitrogen challenge, benefi ting the economy, people’s health and the environment. SANH brings together 32 leading research organisations with governments and other partners. This policy brief provides key insights into national fertiliser trends for all eight SAR countries

Charged-particle pseudorapidity density at mid-rapidity in p–Pb collisions at √sNN = 8.16 TeV

The pseudorapidity density of charged particles, dN(ch)/d eta, in p-Pb collisions has been measured at a centre of-mass energy per nucleon-nucleon pair of root S-NN = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, vertical bar eta vertical bar /2 is 4.73 +/- 0.20, where is the average number of participating nucleons, is 9.5% higher than the corresponding value for p-Pb collisions at root S-NN = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the dN(ch)/d eta distribution. Saturation-based models reproduce the distributions well for eta > -1.3. The dN(ch)/d eta is also measured for different centrality estimators, based both on the charged particle multiplicity and on the energy deposited in the Zero Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p-Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity

Jet fragmentation transverse momentum measurements from di-hadron correlations in √s=7 TeV pp and √sNN=5.02 TeV p–Pb collisions

The transverse structure of jets was studied via jet fragmentation transverse momentum (j(T)) distributions, obtained using two-particle correlations in proton-proton and proton-lead collisions, measured with the ALICE experiment at the LHC. The highest transverse momentum particle in each event is used as the trigger particle and the region 3 < p(Tt) < 15GeV/c is explored in this study. The measured distributions show a clear narrow Gaussian component and a wide non-Gaussian one. Based on Pythia simulations, the narrow component can be related to non-perturbative hadronization and the wide component to quantum chromodynamical splitting. The width of the narrow component shows a weak dependence on the transverse momentum of the trigger particle, in agreement with the expectation of universality of the hadronization process. On the other hand, the width of the wide component shows a rising trend suggesting increased branching for higher transverse momentum. The results obtained in pp collisions at root s TeV and in p-Pb collisions at root sNN=5.02 TeV are compatible within uncertainties and hence no significant cold nuclear matter effects are observed. The results are compared to previous measurements from CCOR and PHENIX as well as to Pythia 8 and Herwig 7 simulations