Features of heavy physics in the CMB power spectrum

The computation of the primordial power spectrum in multi-field inflation models requires us to correctly account for all relevant interactions between adiabatic and non-adiabatic modes around and after horizon crossing. One specific complication arises from derivative interactions induced by the curvilinear trajectory of the inflaton in a multi-dimensional field space. In this work we compute the power spectrum in general multi-field models and show that certain inflaton trajectories may lead to observationally significant imprints of `heavy' physics in the primordial power spectrum if the inflaton trajectory turns, that is, traverses a bend, sufficiently fast (without interrupting slow roll), even in cases where the normal modes have masses approaching the cutoff of our theory. We emphasise that turning is defined with respect to the geodesics of the sigma model metric, irrespective of whether this is canonical or non-trivial. The imprints generically take the form of damped superimposed oscillations on the power spectrum. In the particular case of two-field models, if one of the fields is sufficiently massive compared to the scale of inflation, we are able to compute an effective low energy theory for the adiabatic mode encapsulating certain relevant operators of the full multi-field dynamics. As expected, a particular characteristic of this effective theory is a modified speed of sound for the adiabatic mode which is a functional of the background inflaton trajectory and the turns traversed during inflation. Hence in addition, we expect non-Gaussian signatures directly related to the features imprinted in the power spectrum.Comment: 41 pages, 6 figures, references updated, minor modifications. Version to appear in JCAP. v4: Equations (4.28) and (4.30) and Figures 5 and 6 correcte

Improved breakdown strength and energy storage density of a Ce doped strontium titanate core by silica shell coating

For single phase dielectric ceramics prepared using a traditional solid state method, the conflict between high dielectric permittivity and low breakdown strength has always limited the improvement of energy storage density. Here, we design a core–shell structure of Sr0.985Ce0.01TiO3 (SCT)@x wt% SiO2 combining a high dielectric permittivity core with an insulating shell material. The sample of x = 3 wt% sintered at 1300 °C has the largest energy storage density ∼2.23 J cm−3. The effects that different amounts of SiO2 have on phase, microstructure, dielectric and energy storage properties were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy with energy dispersive X-ray spectrum (SEM-EDS) and dielectric measurements. As verified by finite element simulations, the energy storage properties are mainly governed by the electric field distribution owing to the introduction of a high dielectric permittivity core (SCT) in a low permittivity shell. The shell material provides an electrical shielding effect around the core, resulting in significant reduction in the field strength within the core material. A comparison of experimental and simulated results is also shown, which is in good agreement with the breakdown properties

Microwave spectro-polarimetry of matter and radiation across space and time

From Springer Nature via Jisc Publications RouterHistory: received 2020-07-29, accepted 2021-03-02, registration 2021-03-03, pub-print 2021-06, pub-electronic 2021-07-03, online 2021-07-03Publication status: PublishedAbstract: This paper discusses the science case for a sensitive spectro-polarimetric survey of the microwave sky. Such a survey would provide a tomographic and dynamic census of the three-dimensional distribution of hot gas, velocity flows, early metals, dust, and mass distribution in the entire Hubble volume, exploit CMB temperature and polarisation anisotropies down to fundamental limits, and track energy injection and absorption into the radiation background across cosmic times by measuring spectral distortions of the CMB blackbody emission. In addition to its exceptional capability for cosmology and fundamental physics, such a survey would provide an unprecedented view of microwave emissions at sub-arcminute to few-arcminute angular resolution in hundreds of frequency channels, a data set that would be of immense legacy value for many branches of astrophysics. We propose that this survey be carried out with a large space mission featuring a broad-band polarised imager and a moderate resolution spectro-imager at the focus of a 3.5 m aperture telescope actively cooled to about 8K, complemented with absolutely-calibrated Fourier Transform Spectrometer modules observing at degree-scale angular resolution in the 10–2000 GHz frequency range. We propose two observing modes: a survey mode to map the entire sky as well as a few selected wide fields, and an observatory mode for deeper observations of regions of specific interest

Benzopyrene Diol Epoxide Induced Cell Growth Inhibition is Associated with Down-regulation of p34cdc2: Role of p53

Abstract DNA damage by polynuclear aromatic hydrocarbons (PAHs) is known to trigger cellular protective response of cell growth inhibition. In this regard our previous observation showed G1-S cell cycle arrest (inhibition of DNA synthesis) in human fibroblast associated with accumulation of p53 protein, a known cell growth inhibitory transcription factor, in response to treatment with BPDE (ultimate carcinogenic metabolite of the PAH benzo[a]pyrene). Here we report that BPDE treatment triggers variable extent of cell growth inhibition in different cell lines, and the extent of cell growth inhibition in different cell lines do not correspond to the extent of increased p53 accumulation as opposed to our expectation. We also observed that BPDE treatment of cells significantly down-regulates expression of p34cdc2, a known cell cycle activating protein. Although the role of cdc2 down-regulation in inhibition of cell cycle progression is well known, to the best of our knowledge cdc2 down-regulation in response to cellular insult by PAHs has not been reported. We observed correspondence between extent of cell growth inhibition and the extent of cdc2 down-regulation by BPDE in different cell lines as opposed to p53 accumulation as mentioned above. Interestingly, BPDE-mediated cdc2 down-regulation is observed to be p53 dependent although extent of p53 accumulation does not correspond to the extent of cdc2 down-regulation. However, the extent of cdc2 down-regulation corresponds to the extent of accumulation of cell cycle inhibitor protein p21 (transactivation product of p53) in different cell lines. These findings may have an implication that cell growth inhibition in response to DNA damaging PAHs may involve down-regulation of cdc2 protein elicited by p53 activation (transactivation ability), and the extent of p53 accumulation is not the determining factor in this regard

Comparative metabolism of environmentally occurring phenanthro[3,4-b]thiophene and benzo[c]phenanthrene

Comparative metabolism of environmentally occurring phenanthro[3,4-b]thiophene and benzo[c]phenanthrene Presenters: Subodh Kumar, Jaquan Williams, and Jagat J. Mukherjee Polycyclic aromatic hydrocarbons (PAHs) and their sulfur-heterocyclic analogs (thia-PAHs) are commonly occurring persistent environmental contaminants formed by incomplete combustion of organic matter. A number of thia-PAHs have shown significant mutagenic and carcinogenic activities. As noted with PAHs, these chemical contaminants also require metabolic activation in order to exhibit their mutagenic and carcinogenic effects. In the present study, a comparative metabolism of highly mutagenic phenanthro[3,4-b]thiophene (P[3,4-b]T) and its weakly mutagenic carbon analogue, benzo[c]phenanthrene (B[c]P), were investigated. Metabolism studies were conducted using liver microsomes from induced rats, un-induced rats, as well as lung microsomes from smokers and non-smokers. While all of the microsomes metabolized B[c]P to ring oxidation products (predominantly K-region B[c]P 5,6-diol), P[3,4-b]T is metabolized to both ring oxidation products (predominantly benzo-ring P[3,4-b]T 8,9-diol) and S-oxidation products (predominantly P[3,4-b]T sulfone). P[3,4-b]T is a more potent mutagen than its homocyclic analog B[c]P. Previous studies have shown that, like many carcinogenic PAHs, B[c]P is metabolically activated to B[c]P 3,4-diol to produce mutagenic and carcinogenic effects. However, our recent studies with P[3,4-b]T, have shown that, in contrast to P[3,4-b]T 8,9-diol, a corresponding sulfur analog of B[c]P 3,4-diol, sulfone exhibited significantly higher mutagenic activity compared to P[3,4-b]T. This earlier finding along with our present study, lends support to our hypothesis that unlike B[c]P, P[3,4-b]T exhibits its mutagenic and possibly carcinogenic activity predominantly via sulfoxidation pathway

Total and Single Differential Cross Sections for the Electron Impact Ionization of the Ground State of Helium

Total cross sections (TCS) and single differential cross sections (SDCS) have been computed for the single ionization of the ground state of helium by electron impact in a distorted wave formalism which takes into account the effects of the initial and final channel distortions. The present TCS and SDCS results are in fair agreement with the measured values and other theoretical predictions for the incident electron energy $E_{\rm i} > 150$ eV

Etiology and mode of presentation of chronic liver diseases in India: A multi centric study.

There is a paucity of health policy relevant data for chronic liver disease from India, impeding formulation of an interventional strategy to address the issue. A prospective, multicentric study to delineate the etiology and clinical profile of chronic liver disease in India is reported here. A centrally coordinated and monitored web-based data repository was developed (Feb, 2010 to Jan, 2013) and analyzed. Eleven hospitals from different parts of India participated. Data were uploaded into a web based proforma and monitored by a single centre according to a standardized protocol. 1.28% (n = 266621) of all patients (n = 20701383) attending the eleven participating hospitals of India had liver disease. 65807 (24·68%) were diagnosed for the first time (new cases). Of these, 13014 (19·77%, median age 43 years, 73% males) cases of chronic liver disease were finally analyzed. 33.9% presented with decompensated cirrhosis. Alcoholism (34·3% of 4413) was the commonest cause of cirrhosis while Hepatitis B (33·3%) was predominant cause of chronic liver disease in general and non-cirrhotic chronic liver disease (40·8% out of 8163). There was significant interregional differences (hepatitis C in North, hepatitis B in East and South, alcohol in North-east, Non-alcoholic Fatty Liver Disease in West) in the predominant cause of chronic liver disease. Hepatitis B (46·8% of 438 cases) was the commonest cause of hepatocellular Cancer.11·7% had diabetes. Observations of our study will help guide a contextually relevant liver care policy for India and could serve as a framework for similar endeavor in other developing countries as well