Hunting down the X17 boson at the CERN SPS

Indexación ScopusRecently, the ATOMKI experiment has reported new evidence for the excess of e+e- events with a mass ∼ 17 MeV in the nuclear transitions of 4He, that they previously observed in measurements with 8Be. These observations could be explained by the existence of a new vector X17 boson. So far, the search for the decay X17 → e+e- with the NA64 experiment at the CERN SPS gave negative results. Here, we present a new technique that could be implemented in NA64 aiming to improve the sensitivity and to cover the remaining X17 parameter space. If a signal-like event is detected, an unambiguous observation is achieved by reconstructing the invariant mass of the X17 decay with the proposed method. To reach this goal an optimization of the X17 production target, as well as an efficient and accurate reconstruction of two close decay tracks, is required. A dedicated analysis of the available experimental data making use of the trackers information is presented. This method provides independent confirmation of the NA64 published results [1], validating the tracking procedure. The detailed Monte Carlo study of the proposed setup and the background estimate show that the goal of the proposed search is feasible. © 2020, The Author(s).https://link-springer-com.recursosbiblioteca.unab.cl/article/10.1140%2Fepjc%2Fs10052-020-08725-

Ancient DNA Analysis Affirms the Canid from Altai as a Primitive Dog

The origin of domestic dogs remains controversial, with genetic data indicating a separation between modern dogs and wolves in the Late Pleistocene. However, only a few dog-like fossils are found prior to the Last Glacial Maximum, and it is widely accepted that the dog domestication predates the beginning of agriculture about 10,000 years ago. In order to evaluate the genetic relationship of one of the oldest dogs, we have isolated ancient DNA from the recently described putative 33,000-year old Pleistocene dog from Altai and analysed 413 nucleotides of the mitochondrial control region. Our analyses reveal that the unique haplotype of the Altai dog is more closely related to modern dogs and prehistoric New World canids than it is to contemporary wolves. Further genetic analyses of ancient canids may reveal a more exact date and centre of domestication. © 2013 Druzhkova et al.Peer Reviewe

Assessment of epidemiological situation on hemorhhagic fever with renal syndrome around the world and in Russia, forecast for 2020

© 2020 Russian Research Anti-Plague Institute. All rights reserved. Objective of the review is to characterize the nature of epidemiological situation on HFRS around the world and to conduct a comparative analysis of intensity and dynamics of the epidemiological process in the Russian Federation by Federal Districts, as well as make forecast for 2020. The analysis of the epidemiological situation is based on the materials of the official websites of healthcare organizations in the USA and Europe, WHO, the data from operational monitoring carried out by the reference center for HFRS monitoring “Kazan Research Institute of Epidemiology and Microbiology”, materials provided by the Rospotrebnadzor Institutions in the constituent entities of the Russian Federation. The analysis included all administrative territories of the Russian Federation. Statistical processing was carried out by standard methods of variation statistics applying Excel software. The epidemiological situation on hemorrhagic fever with renal syndrome around the world and in Russia remains tense. In the Russian Federation, epidemically active foci are located in the European part of the country, in Western Siberia and in the Far East. Infections over the period of 2010–2019 were registered in 8 federal districts of the Russian Federation, in 58 constituent entities. However, the incidence distribution across the territory of the country was differential. In 97 % of the cases, the incidence was recorded in the European part of Russia. In the Volga Federal District, HFRS incidence amounted to 82.16 % of the total incidence recorded on the whole in Russia. High incidence rates are also recorded in the Central Federal District (CFD). Over the past 10 years (2010–2019), there has been an increase in the incidence of HFRS in the Central and North-West Federal Districts, and a decrease in the incidence in the Ural and Far Eastern Federal Districts. Varying degree of anthropogenic impact on the natural HFRS foci and climate change manifested in increased ambient air temperatures are of great importance for the spread of HFRS over the past decade. At the end of the review the forecast of the development of the epidemiological situation on HFRS in the Russian Federation for 2020 is presented

Диагностические возможности магнитно-резонансной панкреатохолангиографии с внутривенным контрастированием гадоксетовой кислотой при заболеваниях желчных протоков

Every year the number of operations on the hepatobiliary zone is steadily increasing due to diseases of the bile ducts. Against this background, there is a need for an accurate diagnosis of complications of these interventions; classical magnetic resonance cholangiopancreatography (MRCP) is of limited use. With the introduction of a liver-specific contrast agent (Gd-EOB-DTPA), the possibility of diagnosing diseases of the bile ducts has expanded. In this clinical review, we review the technical aspects and benefits of Gd-EOB-DTPA-enhanced MR cholangiography. Various types of contrast agents, methods of their use in MRI, the dependence of the signal intensity in the bile ducts on the time of administration of the substance, the presence of chronic liver diseases are covered in detail. Separately, studies are given on the diagnosis of diseases of the bile ducts with altered biliary anatomy, biliary fistulas after surgical interventions. In conclusion, data are presented on promising studies of the functional state of the liver based on the use of MRI with hepatotropic contrast enhancement.С каждым годом неуклонно возрастает число операций на гепатобилиарной зоне в связи заболеваниями желчных протоков. На фоне этого возникает потребность в точной диагностике осложнений данных вмешательств, классическая магнитно-резонансная панкреатохолангиография (МРХПГ) имеет ограниченное применение. С внедрением гепатропного контрастного вещества (гадоксетовой кислоты) расширилась возможность диагностики заболеваний желчных протоков. В данном клиническом обзоре мы рассматриваем технические аспекты и преимущество МРХПГ с гепатотропным контрастированием. Подробно освещаются различные виды контрастных веществ, способы их применение при МРТ, зависимость интенсивности сигнала в желчных протоках от времени введения вещества, наличие хронических заболеваний печени. Отдельно приводятся исследования по диагностике заболеваний желчных протоков при измененной билиарной анатомии, желчных свищях после хирургических вмешательств. В заключение приводятся данные о перспективных исследованиях функционального состояния печени на основе применения МРТ с гепатотропным контрастированием

Leptospirosis in the Republic of Tatarstan. Epidemiological Features

The study presents a characteristic of the current epidemiological situation on leptospirosis in the Republic of Tatarstan, investigation of the circulation of leptospirosis agents among the population of small mammals, and the species composition of Leptospira that caused diseases in humans. Materials and methods. The paper contains the data on the incidence of leptospirosis among the population in the Russian Federation (RF) for the period between 2000 and 2018, in the Republic of Tatarstan - since 1998, submitted by the Rospotrebnadzor Administrations in the constituent entities of the Russian Federation, materials of the Center for Hygiene and Epidemiology in the Republic of Tatarstan and the Main Veterinary Administration of the Republic of Tatarstan. Results and discussion. We have carried out the analysis of the epidemiological situation in the Republic of Tatarstan for the period of 1998-2018, by the administrative territories of the republic. The incidence of human leptospirosis caused by various leptospira serogroups has been assessed. In total, 112 people got infected with leptospirosis during the analyzed period. Also the data of epizootiological survey of small mammals inhabiting the natural foci of leptospirosis in the republic are presented. Laboratory tests of 1565 samples from mouse-like rodents for the presence of leptospirosis pathogens have been performed. 1.9 % of the tests gave a positive result. Dominant in the Republic of Tatarstan are the serogroups of Leptospira - Leptospira grippotyphosa and L. hebdomadis. The results of laboratory studies on the carriage of leptospira among small mammals and contamination of environmental objects indicate the circulation of pathogens of leptospirosis in the population of small mammals, habitant in forest shrub, near-water and meadow field stations of the republic. The red vole prevails in this community, the average index of its dominance is 66.7 %. Epizootiological monitoring point to a latent epizootic process in the community of mouse-like rodents

Chromospheric telescope of Baikal Astrophysical Observatory. New light

A chromospheric telescope is an important instrument for synoptic observations and solar research. After several decades of observations with the chromospheric telescope at the Baikal Astrophysical Observatory, a need arose to improve the characteristics of this telescope and filter. A new reimaging lens to produce full-disk solar images 18 mm in diameter at the CCD camera Hamamatsu C-124 with a 36×24 mm detector (4000×2672 pixels) was designed and manufactured to replace the out-of-operation 50×50 mm Princeton Instruments camera. A contrast interference blocking filter and new calcite and quartz crystal plates were made and installed instead of damaged ones in the Hα birefringent filter (BF), manufactured by Bernhard Hallе Nachfl. The optical immersion in the filter was changed. All telescope optics was cleaned and adjusted. We describe for the first time the design features and their related BF passband tuning. The wavefront interferograms of optical elements and telescope as a whole show that the wavefront distortion of the optical path is within 0.25 λ. The BF and prefilter spectral parameters provide high-contrast monochromatic images. Besides, we give examples of solar chromospheric images in the Hα line core and wing

The Dolmen Kolikho, Western Caucasus: Isotopic Investigation of Funeral Practice and Human Mobility

We investigated the dolmen known as Kolikho (Black Sea coast, Russia), discovered accidentally in 2008. It is a unique, undisturbed megalithic structure. The burial chamber contains disarticulated human remains from about 70 individuals. Radiocarbon dating shows that the dolmen was in use between roughly the 19th to 13th centuries BC. Strontium isotopes are used to investigate the origin and last residence location of the people buried in the structure.