bluuebunny/crossref_metadata_2025 huggingface dataset:
Pore network modeling approach for simulating soil water retention curve under different stress conditions
Authors: Mufti Suaiba , Das Arghya
Published: April 2023

The field of unsaturated soil mechanics has recently seen the introduction of pore network models, which attempt to replicate the void structure of porous materials. They are robust physically-based simulation tools and have been used to simulate constitutive relationships like soil water retention curves (SWRC) and unsaturated hydraulic conductivity functions. This work aims to present a pore networkmodeling approach for predicting hysteretic SWRC at various stress states using only grain size distribution and porosity data of the granular soils. The soil sample subjected to given stress conditions is simulated using the Discrete Element Method to obtain a stable packing of spherical particles representing the soil structure. From this packing, an algorithm based on the medial axis is availed to extract a network of pores and throats that describes the geometry and topology of the void structure of the granular soils. Various pore-scale mechanisms like the piston-like advance, corner flow, pore body filling, and snap-off are then used to model fluid displacements at the pore scale to simulate SWRC along the drying and wetting paths. The modeled SWRC under various stress conditions is compared with the measured curves obtained for granular soils from the literature, and the predictions are in good agreement with the experimental results.
Pore scale investigation of unsaturated granular soil behaviour by means ofin situCT experiments
Authors: Milatz Marius , Heinrich Dennis
Published: April 2023

With continuing evolution of imaging techniques from medical applications and materials science, non-destructive imaging experiments have also become an important method to investigate soil specimens. Amongst other methods, computed tomography (CT) has developed to a tool to visualise and better understand the microstructure of different soils based on 3D image data. Furthermore, the acquisition of a temporal series of CT images allows to study processes in soils on the microscale, e. g., during mechanical loading. In order to study the hydraulic and mechanical behaviour of unsaturated granular soils, we combine different custom-built miniaturised experimental set-ups with geomechanics background with computed tomography, yielding so-calledin situCT experiments. By means of image reconstruction and further image analysis based on segmented CT images acquired during different hydraulic and mechanical experiments, we study the drainage and imbibition process as well as the shear process of unsaturated sand and glass bead specimens on the pore or grain scale. The analysis of data on the microscopic level, including the phase distribution, interfacial areas, contact lines as well as radii of curvature of capillary menisci, allows to obtain insights into the macroscopic water retention behaviour and shear behaviour of granular soils.
Numerical analysis of rainfall effects on the slope stability of open pit coal mines
Authors: Theocharis Alexandros , Zevgolis Ioannis , Koukouzas Nikolaos
Published: April 2023

As the world transitions away from coal, vast areas of closed coal mines and waste dumps must be appropriately reclaimed. One critical element for these areas’ safety is slope stability, given the massive slopes of these mines and dumps. This work examines the effect of extreme rainfall on coal mines’ slopestability by incorporating unsaturated soil mechanics principles in a practical way. Past extreme rainfall events recorded for a Greek lignite mining area were used, and climate projections concluded that this intensity is not expected to change. Then, rainfall infiltration was simulated using the Finite Element Method; a typical slope was employed concerning a lignite mining excavation of 200m height and 14° inclination on fine-grained soils. Finally, the stability was calculated using the Limit Equilibrium Method. Rainfall infiltration caused the Safety Factor to decrease, leading to failure. The groundwater rose at theslope’s face from the slope’s toe upwards and led to the development of a smaller and more local than the initial (before rainfall) sliding surface with a lower Safety Factor. Although this is a smaller surface than the initial one, it is still more than 50m high, proposing a significant hazard with severe consequences for the area.
Does gravity affect the thermo-hydro-mechanical processes in a bentonite barrier?
Authors: Villar María Victoria , Gutiérrez-Álvarez Carlos , Iglesias Rubén Javier , Martín Pedro Luis
Published: April 2023

To simulate in the laboratory the conditions of the buffer material in an underground repository for radioactive waste, three tests were performed in instrumented stainless steel cylindrical cells using compacted Wyoming-type bentonite. One of the cells was laid in vertical position and the other two stayed horizontal during operation, with the aim of checking if the layout of the cell affected the results obtained. At one end of the cells, a heater set at 90°C simulated the waste container. After two months of heating, hydration of the bentonite with a saline groundwater started through the surface of the cell opposite to the heater. One of the horizontal cells was dismantled right after the heating phase. After one year of hydration the other two cells were dismantled and the final physical state of the bentonite was analysed in terms of water content and dry density. It was checked that the spatial layout and hence, the effect of gravity, would only be to some extent noticeable if water vapour is involved, i.e. in those phases or processes in which water vapour movement is relevant (namely heating). In the liquid phase the effect of gravity on the water intake and water content and dry density distribution was not noticeable any more.
High Capacity Tensiometers: performance and behaviours
Authors: Mendes Joao , Jamali Armin , Najdi Abdallah , Encalada David , Bruno Agostino W. , Prat Pere C. , Buzzi Olivier , Gallipoli Domenico , Ledesma Alberto , Toll David
Published: April 2023

High capacity tensiometers (HCT) allow the direct measurement of soil matric suction, and their major limitation is the occurrence of cavitation. In this paper HCT designs using different ceramic filters with varied air entry values (AEV), varied reservoir sizes, and different pressure transducers are assessed as to determine the impact that each component may have in the HCT performance. Moreover, the effectiveness of first saturation and resaturation processes is discussed in relation to the time required to prepare/recover HCTs. The results obtained with the different designs show that the measuring range is directly linked to the AEV of the ceramic filter and that the choice of materials used for the various components may affect the reliability of measurements in field installations if the thermal performance is not accounted for in the calibration procedure. The use of a 1hr high vacuum pre-stage followed by overnight water pressurisation at pressures equal or above the AEV of the ceramic filter was found to be the quickest process to fully saturate an HCT for the first time. While resaturation time for an HCT can be reduced to as little as a few minutes if the HCT is resaturated immediately after cavitation has occurred.
Hygro-thermal coupling in earth building materials
Authors: Lalicata Leonardo Maria , Bruno Agostino Walter , Gallipoli Domenico
Published: April 2023

Raw earth is emerging as a viable building material with lower carbon emissions than conventional concrete and fired bricks. Raw earth is as an excellent passive hygro-thermal regulator, which improves occupants’ comfort while reducing the need for active heating/cooling installations. The coupled hygro-thermal response of earth materials is investigated by exploiting the principles of the thermodynamics of porous media and unsaturated soil mechanics. The degree of coupling between temperature and relative humidity (or water content) depends on the adopted simplifying assumptions. Some of these assumptions are valid for traditional building materials but may not be applicable to raw earth characterised by relatively high levels of liquid/gas permeability. The validity of current approaches is here assessed with reference to earth building via a simple one-dimensional transfer model, which simulates the behaviour of an unbounded earth wall subjected to time-dependent boundary conditions on the two faces. For typical values of water and vapour permeability, the complexity of the governing equations can be greatly reduced by neglecting variations of vapour mass and the dependency of suction on temperature without significantly reducing accuracy. Results are also strongly influenced by both initial state and water retention properties of the earth material.
Probability Distribution of Soil Suction of Engineered Turf Cover and Compacted Clay Cover
Authors: Alam Md Jobair Bin , Aggarwal Maalvika
Published: April 2023

It is unlikely to predict the distribution of soil suction in the field deterministically. It is well established that there are various sources of uncertainty in the measurement of matric suction, and the suction measurements in the field are even more critical because of the heterogeneities in the field conditions. Hence it becomes necessary to probabilistically characterize the suction in the field for enhanced reliability. The objective of this study was to conduct a probabilistic analysis of measured soil suction of two different test landfill covers, compacted clay cover (CC) and engineered turf cover (ETC), under similar meteorological events. The size of the two test landfill covers was 3 m × 3 m (10 ft. × 10 ft.) and 1.2 m (4ft.) in depth. The covers were constructed by excavating the existing subgrade, placing 6-mil plastic sheets, and backfilling the excavated soil, followed by layered compaction. Then the covers were instrumented identically with soil water potential sensors up to specified depths. One of the covers acted as the CC, and the other cover was ETC. In ETC, engineered turf was laid over the compacted soil. The engineered turf consisted of a structured LLDPE geomembrane overlain by synthetic turf (polyethylene fibers tufted through a double layer of woven polypropylene geotextiles). The sensors were connected to an automated data logging system and the collected data were probabilistically analyzed using the R program. There were significant inconsistencies in the descriptive statistical parameters of the measured soil suction at both covers under the same climatic conditions. Soil suction measured in the field ranged between almost 12 to 44 kPa in ETC, while it was in the range of almost 1 to 2020 kPa in the CC. The histogram and quantile-quantile (Q-Q) plot showed the data to be non-normally distributed in the field. A heavy-tailed leptokurtic (Kurtosis=13) distribution of suction was observed in the ETC with substantial outliers. In contrast, the suction distribution in CC was observed skewed to the right containing a thinner tail indicating an almost platykurtic distribution. The distribution of suction in the field under engineered turf was observed to be reasonably consistent with time compared to bare soil under the same meteorological events. The results obtained from this study revealed the engineered turf system to be an effective barrier to inducing changes in soil suction against climatic events.
Dynamic modes of the phase number converter based on lc circuits with a common magnetic circuit
Authors: Bazarov Laziz , Bedritsky Ivan , Toshpulatova Durdona , Jurayeva Kamila , Nazirova Zamira
Published: April 2023

Phase multipliers are used in electronic equipment devices when it is not possible to connect to a power source with the required number of phases. Phase multipliers, which are used in single-phase circuits for powering three-phase consumers, have received the greatest application. From the point of view of circuitry, the simplest are multipliers of the number of phases based on nonlinear LC circuits, which have high reliability and relatively small dimensions when powering devices of low and medium power. However, phase multipliers based on LC circuits made on a common magnetic core have degraded dynamic characteristics due to the presence of magnetic bonds between phase-shifting circuits.
A device for detecting current asymmetry in a three-phase alternating current system
Authors: Sattarov Khurshid , Safarov Abdurauf , Kamolov Azamat , Egamberdiev Mannon , Raxmanova Gulnora
Published: April 2023

The article discusses the issues of identifying the asymmetry of currents in a three-phase alternating current system. The design of a current converter designed to detect the unevenness of the current load in parallel branches of the current lines of various power equipment is proposed. It is shown that a positive effect is achieved by making the magnetic circuit four-rod and the introduction of rectangular cutouts with modulating and output windings on two central rods of the magnetic circuit and it is possible to determine the unevenness of the current load of three parallel branches before (in three-phase AC circuits) or after rectifier-converter installations (in DC circuits), therefore, the functionality of the device for detecting current asymmetry is expanded.
Modification of dispersed systems and its effect of the internal corrosion of hydrotransports
Authors: Chorshanbiev Umar , Ibadullaev Ahmadjon , Toshpulatova Durdona , Babaev Askar , Kakharov Baxadir
Published: April 2023

Studies The impact of the modification of dispersed systems of kinematic and dynamic parameters of hydraulic windows, as well as wear in pressure pipes, taking into account the variability of the mechanical composition and the number of hydraulic windows. It is recommended for the modifying additives of the GosIpol resin for dispersed systems and its movements in the cylindrical pipes. The current model that takes into account the concentration of turbidity in the stream and the structural composition of dispersed systems, developed methods of calculation in the process of hydrotransport of modified dispersed systems. The method of calculating the rate of internal corrosion of hydrotransports, specific pressure losses for fluid and solid flow and the effect of variability of the mechanical composition of particles and concentration of turbidity to the flow rate and power of the modified dispersion system is justified, the dependence of the hydraulic friction coefficient from the flow movement mode, taking into account the variability of the solid flow concentration in modified dispersed systems of hydrotransport.
Mathematical modelling of regulatory mechanisms of cell groups functioning at norm and at unregulated cell division
Authors: Saidalieva M. , Hidirova M.B. , Yakubova G. , Yusupova Z.Dj.
Published: April 2023

This paper presents a method for modeling organs and tissues based on the equations of the functional unit of organs and tissues (FUOT) and mathematical models for the main cellular functions: division, growth, differentiation, performance of specific functions, aging, apoptosis and natural death. The elements of FUOT are cells. The analysis shows that there are short circuits of regulation, which in specific realizations of cell development correspond to stable or partially stable cellular structures. This can occur as a normal phenomenon in the form of an adaptive response to stressful influences, and as an abnormal pathological condition. Such partial FUOT can be called minifuot. The study of the proliferative minifuot equations show the presence of a nonzero stable equilibrium position, and a stable limit cycle in the first quadrant. The results of these studies can be useful in studying the mechanisms of cell groups functioning at norm and at unregulated cell division.
Cooling air in contact with natural sources of cold
Authors: Isakhodjayev Kh. , Sohibov A. , Abduvalieva D. , Borotov J. , Bobonov D.
Published: April 2023

Issues of microclimate mitigation in Uzbekistan during the summer period require urgent resolution. It should be noted that currently there are very few research, as well as practical recommendations related to the formation of a favorable microclimatic environment in cities with a hot climate. The simplest and most economical way of cooling, in dry and hot climates, is the evaporative cooling of a dry air stream. One of the possible ways to increase the efficiency of the system is the use of night evaporative cooling of water, followed by its accumulation for daytime cooling in heat-insulated batteries. The conducted experiments testify that rather simple and cheap natural sources of cold can be used along with machine cold sources for air conditioning of residential buildings in Uzbekistan.
Study of optimal temperature during adsorption cleaning of transformer oil under conditions of long-term operation
Authors: Yusupov D.T. , Rakhmatova M. , Tashmatova Sh.
Published: April 2023

The article presents the results of an experimental study of the optimal temperature of a transformer under conditions of long-term operation during adsorption cleaning. The study was conducted on five types of samples of used transformer oil with a long service life.Cleaning of each sample of used transformer oil was carried out at temperature ranges of 20 - 80 °C. Silica gel and zeolite were used for adsorption purification. The conducted experimental studies and analysis of the obtained data showed that the optimum temperature for heating the used oil in the process of adsorption purification is 80°C. Regression equations have been obtained that make it possible to determine the dependence of the oil breakdown voltage on the oil temperature after cleaning with adsorbents. These equations will allow you to predict the expected outcomes without having to perform experimental tests.
Magnetic fluid method for sealing liquid media
Authors: Bolotov Alexander , Burdo Georgy
Published: April 2023

Magnetic fluid seals for sealing gas environments are widely used in various industries due to their undeniable advantages. However, such seals are not capable of reliable sealing of liquid media with different polarities. The paper analyses physicochemical processes that lead to destructing magnetic fluid in a seal under the influence of a liquid medium in contact with it. There are results of experimental studies on sealing using magnetic seals of non-magnetic fluids with different polarity. The authors studied the tightness of a magnetic fluid seal capacity in contact with weakly polar liquids: MVP instrument oil, vaseline oil, and water as a highly polar liquid. For sealing water, the authors chose magnetic fluids with liquid siloxanes as the basis; they are immiscible with water and hydrophobic. Weakly polar liquids were sealed using magnetic fluid with a dispersion medium of triethanolamine, which is almost insoluble in hydrocarbon liquids and has a high dielectric permittivity and surface tension comparable in magnitude. It is established that magnetic fluid based on triethanolamine reliably seals the experimental bearing from penetrating of weakly polar liquids at an overpressure of 10 kPa and below. To seal polar liquid media, it seems promising to use oleophobic magnetic fluids based on PES-5, containing a large amount of filler in the form of ferrite particles. A magnetic fluid should have the smallest possible contact area with the sealed fluid and maintain a laminar flow regime.
Experimental studies of noise and vibration during milling of cast iron parts
Authors: Beskopylny Alexey , Chukarin Alexander , Meskhi Besarion , Dzhedirov Dmitrii
Published: April 2023

Machining processes of cast iron parts are accompanied by significant noise and vibration. Exceeding the standard values of vibration and noise adversely affects the health of the operator and reduces the quality of the final product. The article deals with the scientific problem associated with the study of the causes of increased vibrations and noise during the milling of cast iron products. It has been experimentally shown that the existing ones create increased sound pressure in the range from 250 to 8000 Hz, while the sound pressure level reaches 80-92 dBa, which is 15-20 dBa higher than the maximum allowable. In the higher frequency part of the spectrum, the decrease in the intensity of sound radiation is from 4 to 7 dB per octave. The data obtained are the initial information for the calculation of noise reduction systems, based on compliance with sanitary standards. To simplify engineering calculations, vibrational energy loss coefficients for cast iron solid and hollow products are given.
Features of interaction of carbon primary nanoscale materials with hydrocarbon plasticizers for quality management of polymer modified binders
Authors: Obukhova Svetlana , Korolev Evgenii
Published: April 2023

In present time building materials science is increasingly considering the basic properties of substances, the parameters of phenomena and processes involved in the formation of materials on a nanoscale scale. Carbon nanomaterials due to their structural and energy characteristics, unique mechanical, thermal and optical properties are of increased interest not only as an object of scientific research. But also as an object of technology that provides control of the structure formation of the composite and giving it a level of quality. Phenomena and processes related to the behavior of multilayer carbon nanotubes in hydrocarbon media are considered. Based on the Traxler coefficient a forecast of the type of plasticizer with maximum compatibility with carbon multilayer tubes was carried out. The relationship between the molecular weight of hydrocarbon plasticizers and the concentration of carbon primary nanomaterials in the studied systems on the dispersing ability and stabilizing effect of the medium has been established. The features of the interaction of carbon nanotubes with hydrocarbon plasticizers and their effect on the properties of polymer modified binders were shown.
Physiopathologie et traitements de l’hypertension artérielle pulmonaire
Authors: Perros Frédéric , Jutant Étienne-Marie , Savale Laurent , Dorfmüller Peter , Humbert Marc , Montani David
Published: April 2023

L’hypertension artérielle pulmonaire (HTAP) est une maladie rare affectant principalement le lit vasculaire pulmonaire pré-capillaire. Certaines formes de la maladie présentent néanmoins une atteinte veinulaire/capillaire. Il s’agit d’un remodelage obstructif des artérioles pulmonaires couplé à une raréfaction vasculaire, augmentant la post-charge ventriculaire1 droite et conduisant à une insuffisance cardiaque droite. La physiopathologie de l’HTAP est complexe. Les traitements spécifiques actuels ciblent la dysfonction endothéliale, avec une action essentiellement vasodilatatrice. Des traitements innovants prometteurs ciblant le remodelage vasculaire pulmonaire sont en cours de développement.
A perspective of authenticity degree on the protection of traditional dwellings in ethnic community: The case of the Ma house in Songzhou ancient city
Authors: Tang Zirong
Published: April 2023

As a provincial level historic city, Songpan County in Sichuan Province has a history of more than two thousand years. Locating in the border of three provinces, Songpan was inhabited by multiple ethnic groups. The leading culture here has experienced the baptism and influence of various ethnic cultures such as the Diqiang culture, Mongolian culture, and Tubo culture, and it was not until the Tang Dynasty that the harmonious scene of the coexistence of various ethnic cultures began to be dominated by the Central Plains culture. This research took the Ma house in Songzhou ancient city in Songpan County as the object, which is a representative of local Hui people’s traditional dwellings with a history of three hundred years. Many factors have led to unsystematic protection and renovation to it, and the traces of time was superimposed on it. Therefore, starting from the authenticity degrees of historic building, this paper identified and analysed the timeliness value and spatial value of the Ma house by combining the full information cycle of historic building, which provided a new method and more rational view for the research of historic dwellings.
Analysis of the Persuasion Effect of Micro-Shaping Advertisements based on the Theoretical Framework of Planned Behavior
Authors: He Yang
Published: April 2023

In terms of communication performance, micro-shape advertisements often rely on a variety of advertising persuasion techniques to influence the visual performance of advertisements. Based on this phenomenon, this survey uses a questionnaire to survey the respondents and summarizes the persuasion effect of micro-shape advertisements based on data analysis. This survey found that different factors such as gender, place of origin, and monthly income all affect the persuasion effect of the respondents’ micro-shape advertisements. Therefore, communicators should fully consider the needs of the audience, develop appropriate communication strategies, and comprehensively improve the communication effect of micro-shape advertisements.
Teaching reform of Analog Electronic Technology Experiment Course under the Background of Artificial Intelligence
Authors: Lan Hui , Wang Shunxi
Published: April 2023

This paper briefly describes the implementation of the “multi-level” experimental teaching mode of “combination of hardware and software” and “combination of online and offline” in the experimental course of Analog Electronic Technology, and carries out the experimental teaching reform by combining the problem-oriented teaching mode. It has proved that the reconstructed experimental teaching system has effectively stimulated students’ interest in learning, and the teaching effect has been significantly improved.
Studies on Global Remote Interpreting: A PRISMA Systematic Review
Authors: Feng Cheng
Published: April 2023

This paper conducted a systematic review of remote interpreting based on PRISMA model. The paper is unfolded with introduction of remote interpreting (RI), which tells its history and future development as well as the methodology, which describes the detailed process of identification, screening and including of altogether 36 articles from core journals using PRISMA. Data was collected from research cases over the period 1996-2022. The finding parts show that current studies of remote interpreting is varied in different areas including health care, education, legal settings, technology, and political settings, whose aims and results are all distinguishing and prominent. In conclusion, it can be seen that remote interpreting, a seemingly new technology, has already experienced its infancy and established its foundation in different fields in our society. However, the study also indicates some limitation found in the current studies – for example, the lack of ethical care of interpreters, the adaptability for interpreters into this burgeoning technology, and a better integration of both humans and technology which are not studied in detail yet. Moreover, the review itself also shows some limitation, due to the fact it’s based on the articles from core journals only, to some degree making it less representative.
Research of the Spring Festival Report Overseas in Chinese Mainstream Media: Taking the CGTN as an Example
Authors: Liu Ziyu , Yang Jiazhen , Shi Fangfei
Published: April 2023

In the context of intercultural communication, as a traditional Chinese festival. The Spring Festival (also called Chinese New Year)has caused widespread dissemination overseas. The article takes Chinese mainstream media CGTN’s Chinese New Year related reports released on Youtube platform as research samples, and takes the period of Chinese New Year of the Rabbit in 2023 as the time period for the study. Starting from the video content released by CGTN, the article explores the Chinese image and Chinese symbols shaped by it. And with the support of Frame Theory, the study analyzes the reporting framework from two levels of textual content and value orientation, and further to explore the communication dilemma of Chinese image in the intercultural communication context.
Self-Complementary Dimer of Zinc(II) Porphyrins through Coordination with Oxygen Ligands
Authors: Ke Yuanzhen , Liu Zhichang , Luh Tien-Yau , Wang Hsian-Wen
Published: April 2023

Oxygen ligands have been shown to play a critical role in the formation and organization of metalloporphyrin assemblies and natural chlorosomes. In this work, mutually complementary head-to-tail dimers of zinc(II) porphyrins were synthesized through the coordination of zinc with the imide group and 7-oxanorbornene oxygen ligands. UV/Vis absorption and emission, 1H NMR as well as FT-IR analyses were used to determine the structure. The dimerization association constant K has been determined to be 5.6 M–1 and 29 M–1, respectively, by the dilution experiment.
Negative Pressure Pulmonary Edema after Bilateral Nasal Packing following Transsphenoidal Pituitary Surgery for Nonfunctioning Pituitary Tumor
Authors: Singh Apoorva , Mahajan Shalvi , Aghi Shweta , Kumar Sanjay
Published: April 2023

Negative pressure pulmonary edema (NPPE) is a well-known, albeit infrequent complication caused by upper airway obstruction. It may be seen after extubation following general anesthesia due to excessive negative intrathoracic pressure exerted against an obstructed upper airway. This leads to fluid extravasation from the pulmonary capillaries into the alveolar spaces and lung parenchyma. We report a case of NPPE after endoscopic transsphenoidal resection of the nonfunctional pituitary tumor, which occurred secondary to bilateral nasal packing. Reintubation and positive pressure ventilation were used to manage the patient, who was later extubated after the resolution of features of NPPE.
Dental Professionals' Awareness on Updated Guidelines for Basic Life Support in COVID-19 Patients
Authors: Abhilasha Kumari , Jayanthi D. , Vivekananda Lalith
Published: April 2023

Background Members of dental fraternity have a duty of care to provide safe services to the patients. The satisfactory performance in a medical emergency in dental practice has wide-range implications. But, in the current scenario, the challenge is to ensure that patients with or without coronavirus disease 2019 (COVID-19), who undergo any medical emergency, get the best possible chance of survival without compromising the safety of rescuers, who will be needed to take care for future patients.

Aim This article assesses the awareness and knowledge on interim guidelines for Basic Life Support in adults with suspected or confirmed COVID-19 among various dental health care professionals.

Materials and Methods An online questionnaire-based survey was conducted; framed in Google Forms and sent to various dental health care professionals through WhatsApp, email, and other means. Results were then analyzed and are presented in the form of frequency and percentage.

Results In the study, 224 responders were included comprising undergraduates, postgraduates, and dental practitioners. Dismally, none of them had complete knowledge on the interim guidance for Basic Life Support for suspected or confirmed COVID-19 patients.

Conclusion The study suggests that updated interim guidelines were unknown to maximum percentage of dental professionals which implies that there is need to keep ourselves up-to-date to provide safe services.
Effects of storage time and hydrogen peroxide on the formation of soy globulin 15S in 11S dilute solutions investigated by analytical ultracentrifugation
Authors: Shi Hehang , Ye Xiaodong
Published: April 2023

Two soy protein 11S fractions with different surface sulfhydryl contents were prepared. Utilizing analytical ultracentrifugation, the effects of storage time and hydrogen peroxide at different concentrations (0.5—100 mmol/L) on the two 11S fractions were investigated. Results show that after removing 2-mercaptoethanol (2-ME) by size exclusion chromatography, the 11S fraction with high surface sulfhydryl content (2.0 mol sulfhydryl/mol 11S) progressively formed 15S and 21S in dilute solutions during storage at 4 °C for 82 days. While, the 11S fraction with low surface sulfhydryl content (0.2 mol sulfhydryl/mol 11S) was stable under the same condition. Moreover, after treating the 11S with high surface sulfhydryl content with 1 mmol/L H2O2, the weight percentage of 15S reached the maximum value of 20%. The 15S induced by air and H2O2 could be totally converted to 11S with the addition of 10 mmol/L 2-ME, which could be attributed to that the disulfide bond linking two 11S molecules is on the surface of the 15S and easily accessible to the reducing agent 2-ME. This study helps us to deeply understand the formation mechanism of 15S and the stability of 11S.
Valuing improvements in the ecological integrity of local and regional waters using the biological condition gradient
Authors: Vossler Christian A. , Dolph Christine L. , Finlay Jacques C. , Keiser David A. , Kling Catherine L. , Phaneuf Daniel J.
Published: April 2023

Scientific knowledge related to quantifying the monetized benefits for landscape-wide water quality improvements does not meet current regulatory and benefit–cost analysis needs in the United States. In this study we addressed this knowledge gap by incorporating the Biological Condition Gradient (BCG) as a water quality metric into a stated preference survey capable of estimating the total economic value (use and nonuse) for aquatic ecosystem improvements. The BCG is grounded in ecological principles and generalizable and transferable across space. Moreover, as the BCG translates available data on biological condition into a score on a 6-point scale, it provides a simple metric that can be readily communicated to the public. We applied our BCG-based survey instrument to households across the Upper Mississippi, Ohio, and Tennessee river basins and report values for a range of potential improvements that vary by location, spatial scale, and the scope of the water quality change. We found that people are willing to pay twice as much for an improvement policy that targets their home watershed (defined as a four-digit hydrologic unit) versus a more distant one. We also found that extending the spatial scale of a local policy beyond the home watershed does not generate additional benefits to the household. Finally, our results suggest that nonuse sources of value (e.g., bequest value, intrinsic aesthetic value) are an important component of overall benefits.
Estimating biotic integrity to capture existence value of freshwater ecosystems
Authors: Hill Ryan A. , Moore Chris C. , Doyle Jessie M. , Leibowitz Scott G. , Ringold Paul L. , Rashleigh Brenda
Published: April 2023

The US Environmental Protection Agency (EPA) uses a water quality index (WQI) to estimate benefits of proposed Clean Water Act regulations. The WQI is relevant to human use value, such as recreation, but may not fully capture aspects of nonuse value, such as existence value. Here, we identify an index of biological integrity to supplement the WQI in a forthcoming national stated preference survey that seeks to capture existence value of streams and lakes more accurately within the conterminous United States (CONUS). We used literature and focus group research to evaluate aquatic indices regularly reported by the EPA’s National Aquatic Resource Surveys. We chose an index that quantifies loss in biodiversity as the observed-to-expected (O/E) ratio of taxonomic composition because focus group participants easily understood its meaning and the environmental changes that would result in incremental improvements. However, available datasets of this index do not provide the spatial coverage to account for how conditions near survey respondents affect their willingness to pay for its improvement. Therefore, we modeled and interpolated the values of this index from sampled sites to 1.1 million stream segments and 297,071 lakes across the CONUS to provide the required coverage. The models explained 13 to 36% of the variation in O/E scores and demonstrate how modeling can provide data at the required density for benefits estimation. We close by discussing future work to improve performance of the models and to link biological condition with water quality and habitat models that will allow us to forecast changes resulting from regulatory options.
Structures of Vac8-containing protein complexes reveal the underlying mechanism by which Vac8 regulates multiple cellular processes
Authors: Kim Hyejin , Park Jihyeon , Kim Hyunwoo , Ko Naho , Park Jumi , Jang Eunhong , Yoon So Young , Diaz Joyce Anne R. , Lee Changwook , Jun Youngsoo
Published: April 2023

Vac8, a yeast vacuolar protein with armadillo repeats, mediates various cellular processes by changing its binding partners; however, the mechanism by which Vac8 differentially regulates these processes remains poorly understood. Vac8 interacts with Nvj1 to form the nuclear–vacuole junction (NVJ) and with Atg13 to mediate cytoplasm-to-vacuole targeting (Cvt), a selective autophagy-like pathway that delivers cytoplasmic aminopeptidase I directly to the vacuole. In addition, Vac8 associates with Myo2, a yeast class V myosin, through its interaction with Vac17 for vacuolar inheritance from the mother cell to the emerging daughter cell during cell divisions. Here, we determined the X-ray crystal structure of the Vac8–Vac17 complex and found that its interaction interfaces are bipartite, unlike those of the Vac8–Nvj1 and Vac8–Atg13 complexes. When the key amino acids present in the interface between Vac8 and Vac17 were mutated, vacuole inheritance was severely impaired in vivo. Furthermore, binding of Vac17 to Vac8 prevented dimerization of Vac8, which is required for its interactions with Nvj1 and Atg13, by clamping the H1 helix to the ARM1 domain of Vac8 and thereby preventing exposure of the binding interface for Vac8 dimerization. Consistently, the binding affinity of Vac17-bound Vac8 for Nvj1 or Atg13 was markedly lower than that of free Vac8. Likewise, free Vac17 had no affinity for the Vac8–Nvj1 and Vac8–Atg13 complexes. These results provide insights into how vacuole inheritance and other Vac8-mediated processes, such as NVJ formation and Cvt, occur independently of one another.
Group augmentation underlies the evolution of complex sociality in the face of environmental instability
Authors: Shah Shailee S. , Rubenstein Dustin R.
Published: April 2023

Although kin selection is assumed to underlie the evolution of sociality, many vertebrates—including nearly half of all cooperatively breeding birds—form groups that also include unrelated individuals. Theory predicts that despite reducing kin structure, immigration of unrelated individuals into groups can provide direct, group augmentation benefits, particularly when offspring recruitment is insufficient for group persistence. Using population dynamic modeling and analysis of long-term data, we provide clear empirical evidence of group augmentation benefits favoring the evolution and maintenance of complex societies with low kin structure and multiple reproductives. We show that in the superb starling (
Lamprotornis superbus
)—a plural cooperative breeder that forms large groups with multiple breeding pairs, and related and unrelated nonbreeders of both sexes—offspring recruitment alone cannot prevent group extinction, especially in smaller groups. Further, smaller groups, which stand to benefit more from immigration, exhibit lower reproductive skew for immigrants, suggesting that reproductive opportunities as joining incentives lead to plural breeding. Yet, despite a greater likelihood of becoming a breeder in smaller groups, immigrants are more likely to join larger groups where they experience increased survivorship and greater reproductive success as breeders. Moreover, immigrants form additional breeding pairs, increasing future offspring recruitment into the group and guarding against complete reproductive failure in the face of environmental instability and high nest predation. Thus, plural breeding likely evolves because the benefits of group augmentation by immigrants generate a positive feedback loop that maintains societies with low and mixed kinship, large group sizes, and multiple reproductives.
Ago2 and a miRNA reduce Topoisomerase 1 for enhancing DNA cleavage in antibody diversification by activation-induced cytidine deaminase
Authors: Kobayashi Maki , Wakaguri Hiroyuki , Shimizu Masakazu , Higasa Koichiro , Matsuda Fumihiko , Honjo Tasuku
Published: April 2023

Activation-induced cytidine deaminase (AID) is the essential enzyme for imprinting immunological memory through class switch recombination (CSR) and somatic hypermutation (SHM) of the immunoglobulin (Ig) gene. AID-dependent reduction of Topoisomerase 1 (Top1) promotes DNA cleavage that occurs upon Ig gene diversification, whereas the mechanism behind AID-induced Top1 reduction remains unclear. Here, we clarified the contribution of the microRNA-Ago2 complex in AID-dependent Top1 decrease. Ago2 binds to Top1 3′UTR with two regions of AID-dependent Ago2-binding sites (5′- and 3′dABs). Top1 3′UTR knockout (3′UTRKO) in B lymphoma cells leads to decreases in DNA break efficiency in the IgH gene accompanied by a reduction in CSR and SHM frequencies. Furthermore, AID-dependent Top1 protein reduction and Ago2-binding to Top1 mRNA are down-regulated in 3′UTRKO cells. Top1 mRNA in the highly translated fractions of the sucrose gradient is decreased in an AID-dependent and Top1 3′UTR–mediated manner, resulting in a decrease in Top1 protein synthesis. Both AID and Ago2 localize in the mRNA-binding protein fractions and they interact with each other. Furthermore, we found some candidate miRNAs which possibly bind to 5′- and 3′dAB in Top1 mRNA. Among them, miR-92a-3p knockdown induces the phenotypes of 3′UTRKO cells to wild-type cells whereas it does not impact on 3′UTRKO cells. Taken together, the Ago2-miR-92a-3p complex will be recruited to Top1 3′UTR in an AID-dependent manner and posttranscriptionally reduces Top1 protein synthesis. These consequences cause the increase in a non-B-DNA structure, enhance DNA cleavage by Top1 in the Ig gene and contribute to immunological memory formation.
Synthetically non-Hermitian nonlinear wave-like behavior in a topological mechanical metamaterial
Authors: Xiu Haning , Frankel Ian , Liu Harry , Qian Kai , Sarkar Siddhartha , MacNider Brianna , Chen Zi , Boechler Nicholas , Mao Xiaoming
Published: April 2023

Topological mechanical metamaterials have enabled new ways to control stress and deformation propagation. Exemplified by Maxwell lattices, they have been studied extensively using a linearized formalism. Herein, we study a two-dimensional topological Maxwell lattice by exploring its large deformation quasi-static response using geometric numerical simulations and experiments. We observe spatial nonlinear wave-like phenomena such as harmonic generation, localized domain switching, amplification-enhanced frequency conversion, and solitary waves. We further map our linearized, homogenized system to a non-Hermitian, nonreciprocal, one-dimensional wave equation, revealing an equivalence between the deformation fields of two-dimensional topological Maxwell lattices and nonlinear dynamical phenomena in one-dimensional active systems. Our study opens a regime for topological mechanical metamaterials and expands their application potential in areas including adaptive and smart materials and mechanical logic, wherein concepts from nonlinear dynamics may be used to create intricate, tailored spatial deformation and stress fields greatly transcending conventional elasticity.
Hypoxia induces downregulation of the tumor-suppressive sST2 in colorectal cancer cells via the HIF–nuclear IL-33–GATA3 pathway
Authors: Akimoto Miho , Susa Takao , Okudaira Noriyuki , Koshikawa Nobuko , Hisaki Harumi , Iizuka Masayoshi , Okinaga Hiroko , Takenaga Keizo , Okazaki Tomoki , Tamamori-Adachi Mimi
Published: April 2023

As a decoy receptor, soluble ST2 (sST2) interferes with the function of the inflammatory cytokine interleukin (IL)-33. Decreased sST2 expression in colorectal cancer (CRC) cells promotes tumor growth via IL-33-mediated bioprocesses in the tumor microenvironment. In this study, we discovered that hypoxia reduced sST2 expression in CRC cells and explored the associated molecular mechanisms, including the expression of key regulators of ST2 gene transcription in hypoxic CRC cells. In addition, the effect of the recovery of sST2 expression in hypoxic tumor regions on malignant progression was investigated using mouse CRC cells engineered to express sST2 in response to hypoxia. Our results indicated that hypoxia-dependent increases in nuclear IL-33 interfered with the transactivation activity of GATA3 for ST2 gene transcription. Most importantly, hypoxia-responsive sST2 restoration in hypoxic tumor regions corrected the inflammatory microenvironment and suppressed tumor growth and lung metastasis. These results indicate that strategies targeting sST2 in hypoxic tumor regions could be effective for treating malignant CRC.
Catalytic-assembly of programmable atom equivalents
Authors: Yao Dongbao , Zhang Yunhan , Zhou Xiang , Sun Xiaoyun , Liu Xiaoyu , Zhou Junxiang , Jiang Wei , Hua Wenqiang , Liang Haojun
Published: April 2023

Escape from metastable states in self-assembly of colloids is an intractable problem. Unlike the commonly adopted approach of thermal annealing, the recently developed enthalpy-mediated strategy provided a different option to address this dilemma in a dynamically controllable manner at room temperature. However, it required a complex catalytic-assembly DNA strand-displacement circuitry to mediate interaction between multiple components. In this work, we present a simple but effective way to achieve catalytic-assembly of DNA-functionalized colloidal nanoparticles, i.e., programmable atom equivalents, in a far-from-equilibrium system. A removable molecule named “catassembler” that acts as a catalyst was employed to rectify imperfect linkages and help the system escape from metastability without affecting the assembled framework. Notably, catalytic efficiency of the catassembler can be effectively improved by changing the seesaw catassembler in toehold length design or numbers of the repeat units. Leveraging this tractable catalytic-assembly approach, different ordered architectures were easily produced by directly mixing all reactants, as in chemical reactions. By switching bonding identities, solid–solid phase transformations between different colloidal crystals were achieved. This work opens up an avenue for programming colloid assembly in a far-from-equilibrium system.