bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Diastereoselective Route to Benzoannelated Bridged Sultams
Authors: Sokolov Victor V. , Klochkova Anastasiia A. , Rassadin Valentin A. 
Published: June 2021

AbstractA practical diastereoselective method for the synthesis of benzoannelated tri- and tetracyclic bridged sultams has been developed. The synthetic route employs widely available, substituted o-iodoanilines and is based on intramolecular Michael addition followed by cycloalkylation with α,ω-dihaloalkanes, or vice versa. The target compounds were isolated in good yields and the diastereoselectivity of the reaction could be easily controlled by the order of Michael addition and cycloalkylation steps.
Pandemics and protectionism: evidence from the “Spanish” flu
Authors: Boberg-Fazlic Nina , Lampe Markus , Pedersen Maja Uhre , Sharp Paul 
Published: June 2021

AbstractThe impact of COVID-19 on recent tendencies towards international isolationism has been much speculated on but remains to be seen. We suggest that valuable evidence can be gleaned from the “Spanish” flu of 1918–20. It is well-known that the world fell into a protectionist spiral following the First World War, but scholars have almost exclusively ignored the impact of the pandemic. We employ a difference-in-differences strategy and find that the flu had a significant impact on trade policy, independent of the war. In our preferred specification, a one standard deviation increase in excess deaths during the outbreak implied 0.022 percentage points higher tariffs subsequently, corresponding to an increase of one third of a standard deviation in tariffs. Health policy should aim to avoid the experience of the interwar period and consider the international macroeconomic impact of measures (not) taken.
Characterization of a new SARS-CoV-2 variant that emerged in Brazil
Authors: Imai Masaki , Halfmann Peter J. , Yamayoshi Seiya , Iwatsuki-Horimoto Kiyoko , Chiba Shiho , Watanabe Tokiko , Nakajima Noriko , Ito Mutsumi , Kuroda Makoto , Kiso Maki , Maemura Tadashi , Takahashi Kenta , Loeber Samantha , Hatta Masato , Koga Michiko , Nagai Hiroyuki , Yamamoto Shinya , Saito Makoto , Adachi Eisuke , Akasaka Osamu , Nakamura Morio , Nakachi Ichiro , Ogura Takayuki , Baba Rie , Fujita Kensuke , Ochi Junichi , Mitamura Keiko , Kato Hideaki , Nakajima Hideaki , Yagi Kazuma , Hattori Shin-ichiro , Maeda Kenji , Suzuki Tetsuya , Miyazato Yusuke , Valdez Riccardo , Gherasim Carmen , Furusawa Yuri , Okuda Moe , Ujie Michiko , Lopes Tiago J. S. , Yasuhara Atsuhiro , Ueki Hiroshi , Sakai-Tagawa Yuko , Eisfeld Amie J. , Baczenas John J. , Baker David A. , O’Connor Shelby L. , O’Connor David H. , Fukushi Shuetsu , Fujimoto Tsuguto , Kuroda Yudai , Gordon Aubree , Maeda Ken , Ohmagari Norio , Sugaya Norio , Yotsuyanagi Hiroshi , Mitsuya Hiroaki , Suzuki Tadaki , Kawaoka Yoshihiro 
Published: June 2021

Significance
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are of concern, with the P.1 variants dominating in Brazil. Brazil is now seeing a record number of deaths. Here, we report that the pathogenicity in hamsters of a P.1 variant is similar to that of nonvariant SARS-CoV-2. However, it has an expanded host range as shown by its replication in mice. Prior infection with nonvariant SARS-CoV-2 strains efficiently prevented replication of the P.1 variant in the lower respiratory tract of hamsters upon reinfection. Convalescent sera from patients infected with nonvariants or sera from messenger RNA vaccinees showed comparable neutralization titers among the P.1 and previously circulating strains. These results suggest that previous SARS-CoV-2 infection and vaccines based on the original SARS-CoV-2 will provide some protection against P.1 infection.
Assessment of the potential responses of ecosystem services to anthropogenic threats in the Eten wetland, Peru
Authors: Rojas Tania V. , Bartl Karin , Abad Jorge D. 
Published: June 2021

ABSTRACT

Introduction:
Coastal wetlands are currently threatened by human drivers, such as agriculture, infrastructure development, and urban sprawl. Pressures on these ecosystems disturb their morphology and biogeochemical cycles, resulting in the degradation of ecosystem services. However, little has been done to understand the wetland response to identify proper conservation strategies. Along the Peruvian coast, wetlands present a diversity of landscapes that face similar threats and pressures; however, the ecosystem response in each one may be different.
Objective:
This study aims to assess the environmental impacts on ecosystem services based on the understanding of geomorphic features and the status of the Eten coastal wetland (Peru).
Methods:
The methodology combines the application of open-source GIS tools and the collection of field data to characterize the geomorphic settings and to analyze the changes in environmental parameters. Then, the main threats and pressures on the Eten wetland are defined and related to impacts on ecosystem services using a cause-effect model.
Results:
Overall, the results indicated that the river plays a vital role in defining the wetland landscape and functions. The biological diversity of aquatic habitats is disturbed by hydraulic structures and agricultural activities. Current land use affects supporting and regulation services, such as water regulation.
Inverse moving source problem for time-fractional evolution equations: determination of profiles
Authors: Liu Yikan , Hu Guanghui , Yamamoto Masahiro 
Published: June 2021

Abstract
This article is concerned with two inverse problems on determining moving source profile functions in evolution equations with a derivative order α ∈ (0, 2] in time. In the first problem, the sources are supposed to move along known straight lines, and we suitably choose partial interior observation data in finite time. Reducing the problems to the determination of initial values, we prove the unique determination of one and two moving source profiles for 0 < α ⩽ 1 and 1 < α ⩽ 2, respectively. In the second problem, the orbits of moving sources are assumed to be known, and we consider the full lateral Cauchy data. At the cost of infinite observation time, we prove the unique determination of one moving source profile by constructing test functions.
Operation of the inductively coupled array (INCA) discharge as a para-array
Authors: Lütke Stetzkamp Christian , Tsankov Tsanko Vaskov , Czarnetzki Uwe 
Published: June 2021

Abstract
The inductively coupled array (INCA) discharge is a plasma source with a tailored electric field configuration that allows efficient stochastic heating of the electrons. The desired field configuration is realized by an array of small planar coils. This discharge configuration offers dense plasma production at pressures as low as 0.1 Pa and option for upscaling to square meter sizes. The theoretical works, which led to the development of the INCA discharge, propose two different electric field configurations—the ortho- and the para-configuration. The initial experimental work (P. Ahr et al 2018 Plasma Sources Sci. Technol.
27 105010) studied the ortho-configuration. Here we investigate the performance of the alternative configuration, the para-array, and compare it to the ortho-configuration. The results show similar behaviour of the electrical and of the plasma parameters. However, on first sight the ortho-array appears to perform better. The differences disappear when the power actually coupled to the plasma is considered. For both configurations the electron density follows the same linear trend with the power coupled into the plasma and the electron temperature remains nearly constant as prescribed by the energy balance equation of the electrons. The power coupling efficiency for both configurations increases with the plasma density, approaching 60% at a plasma density of 1 × 1017 m−3. No signs of saturation are observed. The variation of the electron distribution functions with the pressure shows that in the para-configuration the transition into the stochastic heating mode occurs at a pressure twice lower than that for the ortho-array in a very good agreement with the theoretical expectations. Based on the comparison of the discharge parameters and its performance, the advantages and the shortcomings of using one or the other configuration are outlined.
Piezoresistive textile layer and distributed electrode structure for soft whole-body tactile skin
Authors: Lee Hyosang , Park Kyungseo , Kim Jung , Kuchenbecker Katherine J. 
Published: June 2021

Abstract
Tactile sensors based on electrical resistance tomography (ERT) provide pressure sensing over a large area using only a few electrodes, which is a promising property for robotic tactile skin. Most ERT-based tactile sensors employ electrodes only on the sensor’s edge to avoid undesirable artifacts caused by electrode contact. The distribution of these electrodes is critical, as electrode location largely determines the sensitive regions, but only a few studies have positioned electrodes in the sensor’s central region to improve the sensitivity. Establishing the use of internal electrodes on a stretchable textile needs further investigation into piezoresistive structure fabrication, measurement strategy, and calibration. This article presents a comprehensive study of an ERT-based tactile sensor with distributed electrodes. We describe key fabrication details of a layered textile-based piezoresistive structure, an iterative method for choosing the current injection pathways that yields pairwise optimal patterns, and a calibration process to account for the spatially varying sensitivity of such sensors. We demonstrate two sample sensors with electrodes located only on the boundary or distributed across the surface, and we evaluate their performance via three methods widely used to test tactile sensing in biological systems: single-point localization, two-point discrimination, and contact force estimation.
Magnetars and axion-like particles: probes with the hard X-ray spectrum
Authors: Fortin Jean-François , Guo Huai-Ke , Harris Steven P. , Sheridan Elijah , Sinha Kuver 
Published: June 2021

Abstract
Quiescent hard X-ray and soft gamma-ray emission from
neutron stars constitute a promising frontier to explore
axion-like-particles (ALPs). ALP production in the core peaks at
energies of a few keV to a few hundreds of keV; subsequently, the
ALPs escape and convert to photons in the magnetosphere. The
emissivity goes as ∼ T
6 while the conversion probability is
enhanced for large magnetic fields, making magnetars, with their
high core temperatures and strong magnetic fields, ideal targets for
probing ALPs. We compute the energy spectrum of photons resulting
from conversion of ALPs in the magnetosphere and then compare it
against hard X-ray data from NuSTAR, INTEGRAL, and XMM-Newton for a set
of eight magnetars for which such data exists. Upper limits are
placed on the product of the ALP-nucleon and ALP-photon
couplings. For the production in the core, we perform a calculation
of the ALP emissivity in degenerate nuclear matter modeled by a
relativistic mean field theory. The reduction of the emissivity due
to improvements to the one-pion exchange approximation is
incorporated, as is the suppression of the emissivity due to proton
superfluidity in the neutron star core. A range of core temperatures
is considered, corresponding to different models of the steady heat
transfer from the core to the stellar surface. For the subsequent
conversion, we solve the coupled differential equations mixing ALPs
and photons in the magnetosphere. The conversion occurs due to a
competition between the dipolar magnetic field and the photon
refractive index induced by the external magnetic
field. Semi-analytic expressions are provided alongside the full
numerical results. We also present an analysis of
the uncertainty on the axion limits we derive due to the
uncertainties in the magnetar masses, nuclear matter equation of
state, and the proton superfluid critical temperature.
Searching for dark matter particles using Compton scattering *
Authors: Wang Shang , Fu Changbo , Dai De-Chang , Wang Hongwei , Fan Gongtao , Cao Xiguang , Ma Yugang 
Published: June 2021

Abstract
The dark matter puzzle is one of the most important fundamental physics questions in the 21st century. There is no doubt that solving the puzzle will be a new milestone for human beings in achieving a deeper understanding of nature. Herein, we propose the use of the Shanghai laser electron gamma source (SLEGS) to search for dark matter candidate particles, including dark pseudoscalar particles, dark scalar particles, and dark photons. Our simulations indicate that, with some upgrading, electron facilities such as SLEGS could be competitive platforms in the search for light dark matter particles with a mass below tens of keV.
Pile load tests at the deepest foundation piles in Germany
Authors: Katzenbach R , Werner A , Fischer S 
Published: June 2021

Abstract
Since 2001 the so called Hafencity arises in Hamburg, Germany. Currently it is europes biggest urban development project. So far the most famous building of this area is the well known Elbphilharmonie. Now another impressive building is in planning – a huge skyscraper. The new skyscraper will get an over all height of 245 m. Due to the little bearing capacity of the ground a deep foundation is needed. To found the building Germanys deepest foundation piles, with length up to 75 m, will be executed. In advance, to determine the bearing capacity of the surrounding soil, four testpiles, with lengths up to more than 110 m, have been executed.
Impact of a deep foundation on enclosing wall structure of excavation
Authors: Ter-Martirosyan Z G , Vanina Yu V 
Published: June 2021

Abstract
The article provides a solution to the problem of the stress-strain statement of a soil mass with excavation, under the impact of a deep foundation. The solution to the problem is obtained by integrating Melan’s solution. The final expressions for the stress-strain statement components are presented. Isolines of stresses in the soil massif and reactive forces of enclosing wall structure are also given.
Non-destructive method for preliminary assessment of deformation modulus of dispersive soils
Authors: Antipov V V , Ofrikhter V G 
Published: June 2021

Abstract
Modern non-destructive techniques of wave analysis can be applied for the express preliminary geotechnical soil assessment. One of them is Multichannel Analysis of Surface Waves (MASW) which allows obtaining velocities profile of shear waves and the initial shear modulus for the upper section promptly and at minimal labour costs. However, the soil deformation properties assessment requires the deformation modulus that is obtained by the direct technique of plate load test (PLT). The purpose of the study is to assess the correlation between the PLT deformation modulus and the initial shear modulus determined with MASW.
Forecasting of slope stability at the object “Redevelopment of the territory “Mill of Emelyan Bashkirov and his sons”
Authors: Gandelsman I A , Gandelsman A I 
Published: June 2021

Abstract
The article analyzes the current state of the landslide slope of the river Oka, an assessment of landslide risks was made. Various models of ground base behavior in flat setting in the current state and taking into account prospective development are considered. A geometric model of the slope was simulated, using the software complexes “Plaxis” and “GeoStab,” factor of safety and critical sliding surfaces were determined, various anti-landslide designs for maintaining the stability of the slope were considered, technical solutions for performing landslide control were proposed.
Geotechnical properties of hemihydrate and dihydrate phosphogypsum
Authors: Saenko Y V , Shiranov A M , Nevzorov A L 
Published: June 2021

Abstract
The article presents the results of analyses of more than 500 samples of phosphogypsum, which is the waste in the process of phosphorous fertilizers production, consisting of calcium sulfate with admixtures of sulfuric and phosphoric acids, silica and other substances. The characteristics of hemihydrate phosphogypsum (CaSO40,5H2O), in which cementation bonds form as the hydration process proceeds, were studied on undisturbed samples taken in 1 and in 6 months, 1, 5 and 10 years after the material was dumped. It is characterized by low strength and insignificant frost-resistance, which is typical for all building materials and products based on gypsum. The cementation bonds have not been formed in dihydrate phosphogypsum (CaSO4-2H2O) and it remains a non-cohesive granular substance in the dump, so its properties were determined by the methods used in a geotechnics for sands and silty soils. The artificially prepared samples with the relative compaction of 0.80, 0.90 and 0.95 were tested. While the obtained values of the internal friction angle, cohesion and hydraulic conductivity were characteristic for fine sands, the compressibility of this material due to the solubility of the particles was substantially higher. The utilization of phosphogypsum as ground material may have limited use, provided that water protection measures are taken and the acids contained in it are neutralized.
Experimental study results of the strip foundation fragment action underpinned by a drill-injection pile with widening low end
Authors: Samokhvalov M A , Paronko A A , Matyukov A A 
Published: June 2021

Abstract
The article presents the results of static load tests of a strip foundation fragment (bearing plate) underpinned by a drill-injection pile, which has a widening low at its lower end. The static load tests were carried out at the experimental site in the city of Tyumen. A drill-injection pile with widening low end is an injector that has a rubber membrane-glass at its lower end. With the help of a hydraulic packer, the solution is injected into the rubber membrane-glass. After the solution has cured, a widening low end of the required volume is formed at the lower end of the injection pipe. To assess the results obtained, static load tests were also carried out both for a strip foundation fragment without underpinned using a drill-injection pile with widening low end, and a separately located drill-injection pile with widening low end. Based on the data obtained during static load tests in the course of the experimental study, graphs of dependencies were formed: the settlement of a strip foundation fragment on the pressure under its base and the settlement of the drill-injection pile with widening low end on the static load. As a result, it was found that the use of a drill-injection pile with widening low end to underpin a strip foundation fragment allows increasing the bearing capacity by an average of 30%.
Determination of the excess excavation ratio from the data of geodesic monitoring
Authors: Ter-Martirosian A Z , Isaev I O , Almakaeva A S 
Published: June 2021

AbstractIntroduction: During constructing tunnels by trenchless method using the shield driving method soil surface subsides. Buildings and structures which fall into the zone of influence of new construction receive additional settlements. To determine it in the calculations it is necessary to take into account the excess excavation ratio. The purpose of the study is to determine the excess excavation ratio for increasing the sample and determining the normative values of the ratio for application in design.Materials and methods: in the article there is examines the construction of a tunnel in the city of Moscow. Calculations are carried out using the PLAXIS software package in two-dimensional and three-dimensional formulations. In the calculations the normative excess excavation ratio was included and a backward calculation was also carried out in order to determine the actual excess excavation ratio according to the data of geodesic monitoring. Results: the results showed that the excess excavation ratio varies from 0.1% to 1.2%. It is much less than the values that are included in the project according to the regulatory documentation.Conclusions: due to the fact settlement is less than the calculation settlement, the cost of building tunnels can be reduced by reducing the cost of protective measures for buildings and structures, as well as reducing the number of buildings that can receive excess settlement.
Common mistakes made under facility construction in cramped conditions
Authors: Sokolov N S , Viktorova S S , Maguskin V V , Malyanova L I 
Published: June 2021

Abstract
Construction of facilities in cramped conditions requires a special approach connected with the development and implementation of measures to ensure safe operation of the surrounding buildings within the geotechnical influence. Builders often neglect the impact of a new facility construction technology on possible negative effects resulted in the existing buildings (cracks on the facades due to uneven settlement, tilts, etc.). So far the concept of a minimum price has been used when erecting a building part below the zero mark. This approach completely ignores the notion of engineering viability. At the same time builders resort to every kind of trick to reduce the cost of construction. Such an irrational method may eventually result in a substantial increase in the cost of the zero building part construction. As a rule, it can increase the construction time (agreement on a new project when replacing it with another geotechnical technology, and undergoing new expert review). This paper examines a negative case from the geotechnical practice of constructing a 16-storey residential house next to the existing five-storey one.
Development of shell structures in geotechnics and increasing their reliability and safety in modern conditions
Authors: Kasharin D D , Kasharina T P 
Published: June 2021

Abstract
In the interests of sustainable development of the country, improving the quality of the living environment of the population, ensuring environmental safety, it is necessary to create scientific and technological potential, which is noted in the Decree of the President of the Russian Federation and the Resolution of the Government. Based on the foregoing, this article discusses the issues of improving shell structures, composite nanomaterials, their reliability, longevity and stability in natural climatic, technogenic, social and environmental factors. A feature of the above shell structures is their ability to maintain their design shape after various influences, which is laid down in the design and technological processes. The use of shell structures made of various composite (fabric, metal-cord and rubber-fabric, etc.) materials was most widespread in the 70s and 80s of the previous century, which is characterized by the creation of various scientific schools: Sergeev B I - soft hydraulic structures; Petrakov B I -pneumatic dams, pneumatic formwork; Blinov Yu I - awning structures; Ermolov - pneumatic building structures; Stepanovich G Ya, - retaining structures for mine workings, etc. Significant successes in the creation of composite materials were made by foreign firms (Japan, Italy, USA, England, etc.).
Main reasons for strengthening foundations and base soil stabilizations of used buildings
Authors: Polishchuk A I , Semyonov I V , Demchenko V A 
Published: June 2021

Abstract
The paper considers main reasons of strengthening foundations and base soil stabilizations of used buildings. We analyzed more than 120 buildings with various design solutions, which were operated mainly on clay soils, identified reasons and divided them into four groups. The first group is reconstruction of buildings, including their restoration and complete overhaul. The second group is the material destruction of the foundations and a decrease in their waterproofing qualities. The third group is a violation of the stability conditions of foundations during the operation of buildings (structures). The fourth group is the development of significant deformations of buildings during their operations.