ALTICORE: an initiative for coastal altimetry

ALTICORE (value-added ALTImetry for COastal REgions) is an international initiative whose main objective is to encourage the operational use of altimetry over coastal areas, by improving the quality and availability of coastal altimetry data. The ALTICORE proposal has recently been submitted for funding to the INTAS scheme (www.intas.be) by a consortium of partners from Italy, France, UK, Russia and Azerbaijan. ALTICORE is also meant as a contribution to the ongoing International Altimeter Service effort. In this work we will describe the anticipated project stages, namely: 1) improvement of the most widely distributed, 1 Hz, data by analyzing the corrective terms and providing the best solutions, including those derived from appropriate local modelling; 2) development of a set of algorithms to automate quality control and gap-filling functions for the coastal regions; 3) development of testing strategies to ensure a thorough validation of the data. The improved products will be delivered to ALTICORE users via Grid-compliant technology; this makes it easier to integrate the local data holdings, allows access from a range of services, e.g. directly into model assimilation or GIS systems and should therefore facilitate a widespread and complete assessment of the 1Hz data performance and limitations. We will also outline the design and implementation of the Grid-compliant system for efficient access to distributed archives of data; this consists of regional data centres, each having primary responsibility for regional archives, local corrections and quality control, and operating a set of web-services allowing access to the full functionality of data extraction. We will conclude by discussing a follow-on phase of the project; this will investigate further improvements on the processing strategy, including the use of higher frequency (10 or 20 Hz) data. Phenomena happen at smaller spatial scales near the coast, so this approach is necessary to match the required resolution. The whole project will hopefully promote the 15-year sea surface height from altimetry to the rank of operational record for the coastal areas

Energy States of Colored Particle in a Chromomagnetic Field

The unitary transformation, which diagonalizes squared Dirac equation in a constant chromomagnetic field is found. Applying this transformation, we find the eigenfunctions of diagonalized Hamiltonian, that describe the states with definite value of energy and call them energy states. It is pointed out that, the energy states are determined by the color interaction term of the particle with the background chromofield and this term is responsible for the splitting of the energy spectrum. We construct supercharge operators for the diagonal Hamiltonian, that ensure the superpartner property of the energy states.Comment: 25 pages, some calculation details have been removed, typos correcte

Structure, bonding and morphology of hydrothermally synthesised xonotlite

The authors have systematically investigated the role of synthesis conditions upon the structure and morphology of xonotlite. Starting with a mechanochemically prepared, semicrystalline phase with Ca/Si=1, the authors have prepared a series of xonotlite samples hydrothermally, at temperatures between 200 and 250 degrees C. Analysis in each case was by X-ray photoelectron spectroscopy, environmental scanning electron microscopy and X-ray diffraction. The authors’ use of a much lower water/solid ratio has indirectly confirmed the ‘through solution’ mechanism of xonotlite formation, where silicate dissolution is a key precursor of xonotlite formation. Concerning the role of temperature, too low a temperature (~200 degrees C) fails to yield xonotlite or leads to increased number of structural defects in the silicate chains of xonotlite and too high a temperature (>250 degrees C) leads to degradation of the xonotlite structure, through leaching of interchain calcium. Synthesis duration meanwhile leads to increased silicate polymerisation due to diminishing of the defects in the silicate chains and more perfect crystal morphologies

The Development of Travel and Tourism Industry in Iran

The article presents the results of scientific research devoted to the study of tourism in the countries of the Far East, obtained at one of its stages. The purpose of the article is to characterize the state of rural tourism in Iran. The article shows how the attitude to tourism has changed in this country, uncovering the main reasons for the growth of domestic and international tourist flows in recent years. There are several areas of rural tourism in Iran, which include visits to historical villages and free trade zones, camping in nomad tents, recreation in parks and natural resorts, and trips to the desert. The main research findings of the authors demonstrate the problems facing rural tourism in Iran and identify the risks that arise in this sector of the economy

Highly stable defective TiO2-x with tuned exposed facets induced by fluorine: Impact of surface and bulk properties on selective UV/visible alcohol photo-oxidation

Titanium dioxide samples were prepared in the presence of different amounts of fluorine via hydrothermal method. It has been found that the presence of fluoride influenced the physico-chemical properties of TiO2 in various ways as polymorphic form stability, surface hydroxylation, generation of hydroxyl radicals under irradiation and formation of Ti3+ centers and oxygen vacancies. The generation rate of [rad]OH radicals was investigated by the photoluminescence technique in the presence of terephthalic acid. X-ray diffractometry indicated that fluorine stabilized the anatase TiO2. X-Ray photoelectron spectroscopy (XPS) revealed the presence of fluorine on the surface and the shift of the valence band edge towards less negative potentials, electron paramagnetic resonance (EPR) confirmed the formation of Ti3+ in the bulk of the photocatalysts, UV–vis spectra showed the extension of the TiO2 photo-response in the visible light region. 2-Propanol degradation and 4-methoxybenzyl alcohol partial oxidation were studied as probe reactions by using the home prepared powders as photocatalysts. Surprisingly, the photocatalytic activity resulted to be mainly affected by [rad]OH radicals formation ability under irradiation, rather than by the presence of {0 0 1} facets, although it cannot be excluded that the latter could influence the ability to form radicals under irradiation

Acid-Catalyzed Rearrangements of 3-Aryloxirane-2-Carboxamides: Novel DFT Mechanistic Insights

Efficient synthesis of 3-arylquinolin-2(1H)-ones and N-(2-carboxyaryl)-oxalamides from protic acid-catalyzed rearrangements of 3-aryloxirane-2-carboxamides was achieved recently but not well understood. In contrast to the classical Meinwald rearrangement, extensive DFT calculations reveal that the proximal aryl and amide groups have strong synergetic effects to control the amide-aided and aryl-directed oxirane-opening and further rearrangement sequences. The ortho-nitro substituent of the proximal aryl is directly involved in a nucleophilic oxirane ring-opening, the amide C=O is an important proton shuttle for facile H-shifts, while the N-aryl may act as a potential ring-closing site via Friedel-Crafts alkylation. The mechanistic insights are useful for rational design of novel synthesis by changing the aryl and amide functional groups proximal to the oxirane ring

Complex-Radical Terpolymerization of Maleic Anhydride (Styrene), Allyl Propionate and Methyl Methacrylate

The radical terpolymerization reactions of the acceptor-donor-acceptor and donor-acceptor-donor systems, maleic anhydride (MA)-allyl propionate (AP)-methyl methacrylate (MMA) and styrene (St)-MMA-AP, had been studied. The terpolymerizations were carried out in methyl ethyl ketone at 60-75 °C in the presence of 2,2’-azoisobutyronitrile (ABIN) used as the initiator. Some kinetic parameters and copolymerization constants - for both, system were determined by dilatometric and Kelen-Tudos or Seiner-Lift methods. The obtained results are discussed in terms of the free monomer and complex chain growth models. It is shown that terpolymerization was carried out at a stage close to binary copolymerization of MA...AP complex with free MMA and St...MMA complex with AP in the both studied system, respectively. These systems are also used as model for interpretation of cyclocopolymerization mechanism in allyl methactylate-MA (or St) system. DTA and TGA analyses indicated the relatively high thermal stability of St-MMA-AP terpolymer. It is shown that this terpolymer decomposes through a one-step reaction at 310 °C, however MA-AP-MMA terpolymer decomposes through a multi-step reactions at 150, 260 and 310 °C

Immunological efficacy and tolerability of vaccination in patients with noncommunicable diseases

Aim. To study the efficacy and tolerability of Sputnik V vaccination in patients with noncommunicable diseases (NCDs) compared with healthy individuals.Material and methods. The retrospective analysis included data from 800 men and women aged 18 to 90 who were vaccinated from February to May 2021 at the National Medical Research Center for Therapy and Preventive Medicine. Sputnik V (Gam-COVID-Vac, Russia), consisting of two doses, was used as a vaccine. The mean age of the patients was 50,46±13,16 years. Patients were questioned in two stages: before vaccination and after the first dose of vaccination. The following clinical and paraclinical investigations were carried out: saturation assessment, measurement of temperature, blood pressure and heart rate at rest, pharynx examination, auscultation of the heart and respiratory organs. The blood concentration of antibodies (IgM and IgG) was determined after 21 days and 42 days. For analysis, patients were divided into three groups. The first group included healthy individuals (n=238, 29,8%), the second group — patients with one NCD (n=385, 48,1%), and the third group — patients with two or more NCDs (n=177, 22,1%).Results. The sex composition was comparable in all three groups, while the mean age differed. In the first group, the mean age was 43,93±10,80 years, while in the second and third groups — 50,51±12,55 and 59,12±12,37 years, respectively (p<0,001). Statistical analysis was performed with adjustment for age and sex. The median blood concentration of immunoglobulin G of vaccinated individuals of the cohort after 21 days was within 4,60 [2,00; 8,40]. A comparative analysis of the groups did not reveal significant differences. After 42 days, the median concentration of immunoglobulin G increased by 4 times, which is significant (p<0,001) and amounted to 16,20 [15,80; 16,40]. In the group of healthy individuals, the concentration of immunoglobulin G was significantly higher compared to groups of individuals with one, as well as two or more NCDs. Forty-two days after vaccination, the concentration of immunoglobulin M both in the cohort and in individual groups did not change significantly compared to the level after 21 days. In addition, 47%, 38% and 40% of participants from the first, second and third groups, respectively, reported some symptoms. A temperature increase on average was detected in 13% of vaccinated individuals. The largest number of persons with fever was registered in the group of healthy individuals — 19%, in the group of patients with one NCD — 14%, and in the group with two or more diseases, the temperature increase was the lowest and amounted to 3% (p<0,001). After the first dose, 18,6% of patients reported taking additional drugs as follows: first group — 23,9%, second group — 15,1%, third group — 19,2%. These are mainly analgesic, non-steroidal anti-inflammatory and antihistamine drugs.Conclusion. Vaccination with Sputnik V increases the immunoglobulin G level in the blood after 42 days by four times compared to after 21 days. This pattern is observed both in the group of healthy individuals and in patients with one, two or more chronic NCDs. Tolerability of vaccination in all groups was comparable and did not lead to visits to healthcare facilities

Ancient genomic time transect from the Central Asian Steppe unravels the history of the Scythians

The Scythians were a multitude of horse-warrior nomad cultures dwelling in the Eurasian steppe during the first millennium BCE. Because of the lack of first-hand written records, little is known about the origins and relations among the different cultures. To address these questions, we produced genome-wide data for 111 ancient individuals retrieved from 39 archaeological sites from the first millennia BCE and CE across the Central Asian Steppe. We uncovered major admixture events in the Late Bronze Age forming the genetic substratum for two main Iron Age gene-pools emerging around the Altai and the Urals respectively. Their demise was mirrored by new genetic turnovers, linked to the spread of the eastern nomad empires in the first centuries CE. Compared to the high genetic heterogeneity of the past, the homogenization of the present-day Kazakhs gene pool is notable, likely a result of 400 years of strict exogamous social rules.Introduction Results - The IA transition in the Kazakh Steppe - Admixture modeling of IA steppe populations - Post-IA genetic turnovers in the Kazakh Steppe - Dating ancient admixture - Present-day Kazakhs Discussion Material and methods - Radiocarbon dating - DNA extraction, library preparations, and sequencing - Modern DNA genotyping and quality controls - Ancient DNA data processing -- Raw data -- Authentication and contamination estimate -- Genotyping -- Sex determination -- Genetic relatedness estimation - Uniparental haplogroup assignment - Population structure analyses - Individual labeling and population grouping criteria - F-statistics and ancestry modeling - Admixture dating - CHROMOPAINTER and fineSTRUCTURE analyse