Two-loop renormalization group restrictions on the standard model and the fourth chiral family

In the framework of the two-loop renormalization group, the global profile of the Standard Model (SM) in its full parameter space is investigated up to the scale of the gauge singularity. The critical Higgs masses bordering the strong coupling, unstable and the safe regions are explicitly found. Restrictions on the Higgs boson mass as a function of a cutoff scale are obtained from the stability of the electroweak vacuum and from the absence of the strong coupling both in the Higgs and Yukawa sectors. The cutoff being equal to the Plank scale requires the Higgs mass to be M=(161.3+-20.6)+4-10 GeV and M>=140.7+-10 GeV, where the M corridor is the theoretical one and the errors are due to the top mass uncertainty. The SM two-loop beta-functions are generalized to the massive neutrino case. Modification of the two-loop global profile of the SM extended by one new chiral family is studied, and bounds on the masses of the family are found. The requirement of self-consistency of the perturbative SM as an underlying theory up to the Planck or GUT scale excludes the fourth chiral family with the mass up to 250 GeV depending on the Higgs mass and the cutoff scale. Under precision experiment restriction M<=200 GeV, the fourth chiral family, taken alone, is excluded. Nevertheless a pair of the chiral families constituting the vector-like one could still exist.Comment: 22 LaTeX pages, 17 PostScript figures. In the 2nd version of the e-print a typo in the 2-loop beta function of a charged lepton is correcte

Black Hole Shadows: How to Fix the Extended Gravity Theory

The first images of black hole shadows open new possibilities to develop modern extended gravity theories. We discuss the shadow calculations in non-rotating case both when $g_{11} = - g_{00}^{-1}$ and $g_{11} \neq - g_{00}^{-1}$. We demonstrate the application to few different models: Horndesky theory with Gauss-Bonnet invariant, loop quantum gravity and conformal gravity. The difference of these theories from shadow models with the theory of general relativity is shown. In addition we show that when the rotation is taken into account the requirements to the observational accuracy decrease

ОПЫТ ПРИМЕНЕНИЯ РИВАРОКСАБАНА У ПАЦИЕНТОВ С ТРЕПЕТАНИЕМ ПРЕДСЕРДИЙ 1-ГО ТИПА: ЭФФЕКТИВНОСТЬ, БЕЗОПАСНОСТЬ, КОМПЛАЕНТНОСТЬ

Aim. To assess effectiveness, safety and adherence to treatment of patients with type I atrial flutter who were previously excluded from the clinical trials evaluating the potential benefits of rivoroxaban for thromboembolism prevention.Methods. 27 medical records of patients with type I atrial flutter were retrospectively reviewed and assigned to the study group. The control group consisted of 100 patients with atrial fibrillation. Both groups received rivoroxaban. All patients underwent thromboembolism risk assessment with the CHA2DS2-VACs score, bleeding risk assessment with HAS-BLED score. Data were collected by telephone.Results. No thromboembolic events were registered in the atrial flutter group, whereas one case of ischemic stroke was in the atrial fibrillation group. There were no major bleedings in both groups. Four patients with atrial flutter and 2 patients with atrial fibrillation had hemorrhages. Patients’ adherence to rivoroxaban was 75–80%.Conclusion. Rivoroxaban therapy was found to be effective and safe in patients with type I atrial flutter including those who underwent cardioversion. High adherence to rivoroxaban therapy was demonstrated.Цель. Оценить с позиции безопасности, эффективности и комплаентности к лечению группу пациентов с трепетанием предсердий 1-го типа, ранее не включенных в рандомизированные исследования по вопросам профилактики тромбоэмболических осложнений на фоне приема ривароксабана.Материалы и методы. Исследование имело ретроспективный характер, в исследование включено 27 пациентов с трепетанием предсердий 1-го типа, группой сравнения стали 100 пациентов с фибрилляцией предсердий. Обе группы в качестве антитромботической поддержки получали ривароксабан, пациентам проводили оценку риска тромбоэмболии о шкале CHA2DS2-VASc, оценку риска кровотечений по шкале HAS-BLED использовался метод сбора информации путем телефонного анкетирования.Результаты. В группе трепетания предсердий не зафиксировано тромбоэболических осложнений, в группе фибрилляции предсердий выявлен один случай ишемического инсульта, значимых кровотечений не было ни в одной из групп. Геморрагический синдром зафиксирован у четырех пациентов с трепетанием предсердий и у двух – в группе фибрилляции предсердий. Комплаентность к терапии ривароксабаном составила 75–80% в обеих группах.Заключение. Подтверждена эффективность и безопасность ривароксабана у пациентов с трепетанием предсердий 1-го типа, в том числе для антитромботической поддержки кардиоверсии, а также высокий комплайнс к подобному лечению