Black hole production in tachyonic preheating

We present fully non-linear simulations of a self-interacting scalar field in the early universe undergoing tachyonic preheating. We find that density perturbations on sub-horizon scales which are amplified by tachyonic instability maintain long range correlations even during the succeeding parametric resonance, in contrast to the standard models of preheating dominated by parametric resonance. As a result the final spectrum exhibits memory and is not universal in shape. We find that throughout the subsequent era of parametric resonance the equation of state of the universe is almost dust-like, hence the Jeans wavelength is much smaller than the horizon scale. If our 2D simulations are accurate reflections of the situation in 3D, then there are wide regions of parameter space ruled out by over-production of black holes. It is likely however that realistic parameter values, consistent with COBE/WMAP normalisation, are safetly outside this black hole over-production region.Comment: 6pages, 7figures, figures correcte

Trans-Planckian Particle Creation in Cosmology and Ultra-High Energy Cosmic Rays

We consider observational constraints on creation of particles induced by hypothetical trans-Planckian effects during the current stage of the Universe expansion. We show that compatibility with the diffuse gamma-ray background measured by the EGRET experiment strongly restricts this creation. In particular, it rules out the possibility to detect signatures of such short distance effects in anisotropies of the cosmic microwave background radiation. On the other hand, a possibility that some part of the ultra-high energy cosmic rays originates from new trans-Planckian physics remains open.Comment: Typos are correcte

Cosmic structure formation in Hybrid Inflation models

A wide class of inflationary models, known as Hybrid Inflation models, may produce topological defects during a phase transition at the end of the inflationary epoch. We point out that, if the energy scale of these defects is close to that of Grand Unification, then their effect on cosmic structure formation and the generation of microwave background anisotropies cannot be ignored. Therefore, it is possible for structure to be seeded by a combination of the adiabatic perturbations produced during inflation and active isocurvature perturbations produced by defects. Since the two mechanisms are uncorrelated the power spectra can be computed by a weighted average of the individual contributions. We investigate the possible observational consequences of this with reference to general Hybrid Inflation models and also a specific model based on Supergravity. These mixed perturbation scenarios have some novel observational consequences and these are discussed qualitatively.Comment: 22 Page

Clinical and laboratory characteristics of tick-borne rickettsiosis related to <i>Rickettsia sibirica</i> and <i>Candidatus Rickettsia tarasevichiae</i>

The Siberian tick-borne typhus (STT) is the most common tick-borne rickettsiosis (TBR) in Russia, registered in 17 administrative territories of the Southern Siberia and the Far East. The aim of this study was to describe clinical picture, pathological data and results of laboratory diagnostics during fatal mixed infection caused by two Rickettsia species most common in Russia — pathogenic Rickettsia sibirica and poorly examined Candidatus R. tarasevichiae, including identification of its etiological agents. A four-year-old girl in Krasnoyarsk Krai in a hyperendemic focus of the Siberian tick-borne typhus after tick sucking revealed typical TBR symptoms (scab at the site of tick suction, fever, spotted rash, myalgia) and meningeal syndrome, which is not typical for the Siberian tick-borne typhus. The child died on the seventh day of illness. Autopsy data (hepatosplenomegaly; cerebral edema, which was the immediate cause of death) and the results of histological examination (productive vasculitis of the brain, spinal cord and skin, polymorphic cell perivascular infiltrates in the liver and lungs, serous meningitis, myeloid hyperplasia of the spleen and lymph nodes, interstitial lymphoid infiltration in the myocardium) confirmed the clinical diagnosis of tick-borne rickettsiosis. The patient’s blood and brain samples were tested for a wide range of tick-borne pathogens and enteric viruses that cause brain damage using PCR followed by sequencing of the positive samples. The DNA of Rickettsia sibirica and Candidatus Rickettsia tarasevichiae was found in both blood and brain samples. R. sibirica was identified by the nucleotide sequences of gene fragments gltA, ompA and ompB, and Candidatus R. tarasevichiae — by the gltA and ompB genes using nested PCR and sequencing. All amplified fragments were sequenced in both directions; the obtained sequences were deposited in the GenBank database under the inventory numbers MK048467–MK048475. We have not identified other tick-borne pathogens or intestinal viruses in the patient samples able to result in meningeal syndrome. The area where the child was sucked by the tick belongs to the regions with a high incidence of STT. Several species of mites coexist in this area; of these, Haemaphisalis concinna, the carrier of R. sibirica, dominates the populations of Ixodes mites, while Ixodes persulcatus, the main reservoir of Candidatus R. tarasevichiae, is less common. As a result of the conducted studies, for the first time in the Russian Federation, a verified case of a lethal infection associated with two species of Rickettsia — Rickettsia sibirica and Candidatus R. tarasevichiae — was identified and described

Matter Creation via Vacuum Fluctuations in the Early Universe and Observed Ultra-High Energy Cosmic Ray Events

Cosmic rays of the highest energy, above the Greisen-Zatsepin-Kuzmin cut-off of the spectrum, may originate in decays of superheavy long-living X-particles. These particles may be produced in the early Universe from vacuum fluctuations during or after inflation and may constitute a considerable fraction of Cold Dark Matter. We calculate numerically their abundance for a wide range of models. X-particles are considered to be either bosons or fermions. Particles that are several times heavier than inflaton, m_inflaton \approx 10^{13} GeV, and were produced by this mechanism, can account for the critical mass in the Universe naturally. In some cases induced isocurvature density fluctuations can leave an imprint in anisotropy of cosmic microwave background radiation.Comment: LaTeX, 9 page

Convergent functional genomic studies of omega-3 fatty acids in stress reactivity, bipolar disorder and alcoholism

Omega-3 fatty acids have been proposed as an adjuvant treatment option in psychiatric disorders. Given their other health benefits and their relative lack of toxicity, teratogenicity and side effects, they may be particularly useful in children and in females of child-bearing age, especially during pregnancy and postpartum. A comprehensive mechanistic understanding of their effects is needed. Here we report translational studies demonstrating the phenotypic normalization and gene expression effects of dietary omega-3 fatty acids, specifically docosahexaenoic acid (DHA), in a stress-reactive knockout mouse model of bipolar disorder and co-morbid alcoholism, using a bioinformatic convergent functional genomics approach integrating animal model and human data to prioritize disease-relevant genes. Additionally, to validate at a behavioral level the novel observed effects on decreasing alcohol consumption, we also tested the effects of DHA in an independent animal model, alcohol-preferring (P) rats, a well-established animal model of alcoholism. Our studies uncover sex differences, brain region-specific effects and blood biomarkers that may underpin the effects of DHA. Of note, DHA modulates some of the same genes targeted by current psychotropic medications, as well as increases myelin-related gene expression. Myelin-related gene expression decrease is a common, if nonspecific, denominator of neuropsychiatric disorders. In conclusion, our work supports the potential utility of omega-3 fatty acids, specifically DHA, for a spectrum of psychiatric disorders such as stress disorders, bipolar disorder, alcoholism and beyond

Short-course preoperative radiotherapy combined with chemotherapy, delayed surgery and local hyperthermia for rectal cancer: a phase II study

Purpose: The aim of this study was to investigate the feasibility of short-course radiotherapy with oral capecitabine, hyperthermia and delayed surgery for neoadjuvant treatment of rectal cancer.Methods: Patients with clinically staged T2-3N0-2M0 primary rectal cancer were included. All patients received short-course 25Gy in 5Gy fractions radiotherapy with capecitabine, local hyperthermia and metronidazole. Capecitabine 1000mg/m(2) twice a day was given on days 1-14. Local hyperthermia, 41-45 degrees C for 60min, was performed on days 3-5. Metronidazole 10g/m(2) was administered per rectum on days 3 and 5. The time interval to surgery was not less than four weeks after neoadjuvant treatment. The primary end-point was pathological complete response (pCR). Secondary end-points included neoadjuvant treatment toxicity, tumour regression, surgical and oncological outcomes.Results: A total of 81 patients were included in the analysis. Ten (12.3%) patients had grade 3 toxicity and one (1.2%) patient had grade 4 toxicity. Sphincter-sparing surgery was performed for 78 (96.3%) patients. There was no postoperative mortality. Postoperative complications occurred in 11 (13.8%) patients. Sixteen (20%) patients had a pCR. The median follow-up was 40.9 months. There were no local recurrences. Nine (11.1%) patients developed distant metastases. Three-year overall survival was 97% and the three-year disease-free survival was 85%.Conclusions: Short-course radiotherapy with chemotherapy, radiosensitizers and delayed surgery is a feasible treatment for rectal cancer and may lead to tumour regression rate comparable with long-course chemoradiation

New development of radiopure ZnWO4 crystal scintillators

The residual radioactive contaminations of zinc tungstate crystal scintillators, produced by low-thermal-gradient Czochralski technique in various conditions, have been measured in the DAMA/R&amp;D; low background setup at the Gran Sasso National Laboratory (INFN, Italy). The total alpha activity has been measured in the detectors realized with different processes to vary between 158 and 1418 μ Bq/kg. The internal 228 Th contamination activity has been estimated as 0.34 μ Bq/kg in the most polluted crystal, while only upper limits for other ones have been set at level from &lt; 0.17 μ Bq/kg to &lt; 1.3 μ Bq/kg. These results open possibility for further radio-purifications of ZnWO 4 crystal scintillators, which are of potential interests in various fields