bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeting PirAvp and PirBvp Toxins of Vibrio parahaemolyticus with Oilseed Peptides: An In Silico Approach
Authors: Ong Joe-Hui , Wong Wey-Lim , Wong Fai-Chu , Chai Tsun-Thai
Published: October 2021

Acute hepatopancreatic necrosis disease (AHPND), caused by PirAvp- and PirBvp-releasing Vibrio parahaemolyticus strains, has resulted in massive mortality in shrimp aquaculture. Excessive use of antibiotics for AHPND management has led to antibiotic resistance, highlighting the urgency to search for alternatives. Using an in silico approach, we aimed to discover PirAvp/PirBvp-binding peptides from oilseed meals as alternatives to antibiotics. To search for peptides that remain intact in the shrimp digestive tract, and therefore would be available for toxin binding, we focused on peptides released from tryptic hydrolysis of 37 major proteins from seeds of hemp, pumpkin, rape, sesame, and sunflower. This yielded 809 peptides. Further screening led to 24 peptides predicted as being non-toxic to shrimp, fish, and humans, with thermal stability and low water solubility. Molecular docking on the 24 peptides revealed six dual-target peptides capable of binding to key regions responsible for complex formation on both PirAvp and PirBvp. The peptides (ISYVVQGMGISGR, LTFVVHGHALMGK, QSLGVPPQLGNACNLDNLDVLQPTETIK, ISTINSQTLPILSQLR, PQFLVGASSILR, and VQVVNHMGQK) are 1139–2977 Da in mass and 10–28 residues in length. Such peptides are potential candidates for the future development of peptide-based anti-AHPND agents which potentially mitigate V. parahaemolyticus pathogenesis by intercepting PirAvp/PirBvp complex formation.
Investigating the Effect of an Oxytetracycline Treatment on the Gut Microbiome and Antimicrobial Resistance Gene Dynamics in Nile Tilapia (Oreochromis niloticus)
Authors: Payne Christopher J. , Turnbull James F. , MacKenzie Simon , Crumlish Margaret
Published: October 2021

Antibiotics play a vital role in aquaculture where they are commonly used to treat bacterial diseases. However, the impact of antibiotic treatment on the gut microbiome and the development of antimicrobial resistance in Nile tilapia (Oreochromis niloticus) over time remains to be fully understood. In this study, fish were fed a single treatment of oxytetracycline (100 mg/kg/day) for eight days, followed by a 14-day withdrawal period. Changes in the distal gut microbiome were measured using 16S rRNA sequencing. In addition, the abundance of antimicrobial resistance genes was quantified using real-time qPCR methods. Overall, the gut microbiome community diversity and structure of Nile tilapia was resilient to oxytetracycline treatment. However, antibiotic treatment was associated with an enrichment in Plesiomonas, accompanied by a decline in other bacteria taxa. Oxytetracycline treatment increased the proportion of tetA in the distal gut of fish and tank biofilms of the treated group. Furthermore, the abundance of tetA along with other tetracycline resistance genes was strongly correlated with a number of microbiome members, including Plesiomonas. The findings from this study demonstrate that antibiotic treatment can exert selective pressures on the gut microbiome of fish in favour of resistant populations, which may have long-term impacts on fish health.
Analysis of Lipophilic Antioxidants in the Leaves of Kaempferia parviflora Wall. Ex Baker Using LC–MRM–MS and GC–FID/MS
Authors: Song Kihwan , Saini Ramesh Kumar , Keum Young-Soo , Sivanesan Iyyakkannu
Published: October 2021

Lipophilic metabolites such as carotenoids, fatty acids, vitamin K1, phytosterols, and tocopherols are important antioxidants that are used in the cosmetics, foods, and nutraceutical industries. Recently, there has been a growing demand for the use of byproducts (wastes) as a potential source of industrially important compounds. The leaves of Kaempferia parviflora (black ginger) (KP-BG) are major byproducts of KP-BG cultivation and have been reported to contain several bioactive metabolites; however, the composition of lipophilic metabolites in KP-BG leaves has not been examined. In this study, the lipophilic antioxidant profile was analyzed in the leaves of KP-BG plants grown in vitro and ex vitro. Lipophilic compounds, namely carotenoids (80.40–93.84 µg/g fresh weight (FW)), tocopherols (42.23–46.22 µg/g FW), phytosterols (37.69–44.40 µg/g FW), and vitamin K1 (7.25–7.31 µg/g FW), were quantified using LC–MRM–MS. The fatty acid profile of the KP-BG leaves was identified using GC–FID/MS. The content of individual lipophilic compounds varied among the KP-BG leaves. Ex vitro KP-BG leaves had high levels of lutein (44.38 µg/g FW), α-carotene (14.79 µg/g FW), neoxanthin (12.30 µg/g FW), β-carotene (11.33 µg/g FW), violaxanthin (11.03 µg/g FW), α-tocopherol (39.70 µg/g FW), α-linolenic acid (43.12%), palmitic acid (23.78%), oleic acid (12.28%), palmitoleic acid (3.64%), total carotenoids (93.84 µg/g FW), and tocopherols (46.22 µg/g FW) compared with in vitro KP-BG leaves. These results indicate that ex-vitro-grown KP-BG leaves could be used as a valuable natural source for extracting important lipophilic antioxidants.
Co(II) Complex of Quercetin–Spectral, Anti-/Pro-Oxidant and Cytotoxic Activity in HaCaT Cell Lines
Authors: Kalinowska Monika , Lewandowska Hanna , Pruszyński Marek , Świderski Grzegorz , Gołębiewska Ewelina , Gryko Kamila , Braun Julia , Borkowska Monika , Konieczna Magda , Lewandowski Włodzimierz
Published: October 2021

In this study a cobalt(II) complex of quercetin was synthetized in the solid state with the general formula Co(C15H9O7)2∙2H2O. The FT-IR, elemental analysis, and UV/Vis methods were used to study the composition of the complex in a solid state and in a water solution. The anti-/pro-oxidant activity of quercetin and the Co(II) complex was studied by means of spectrophotometric DPPH (2,2-diphenyl-1-picrylhydrazyl), FRAP (ferric reducing antioxidant activity) and Trolox oxidation assays. The cytotoxicity of quercetin and Co(II)-quercetin complex in HaCat cell lines was then established.
Time-Dependent Damage Estimation of a High-Rise Steel Building Equipped with Buckling-Restrained Brace under a Series of Earthquakes and Winds
Authors: Naqi Ahmad , Roy Tathagata , Saito Taiki
Published: October 2021

This study investigates the cumulative damage of a 20-story high-rise steel building equipped with buckling-restrained braces (BRB) under the likely occurrence of earthquake and wind events in the design life of the building. The objective of this research is to introduce a method for evaluating the cumulative damage of BRBs under multi-hazard events that are expected to occur during the service life of a high-rise building in order to achieve a safer building. A methodology is proposed using a Poisson point process to estimate the timeline of earthquake and wind events, wherein the events are assumed to be independent in nature. The 20-story high-rise steel building with BRBs is designed according to the Japanese standard and analyzed using the finite element approach, considering nonlinearities in the structural elements and BRBs. The building is analyzed consecutively using the timeline of earthquakes and winds, and the results are compared with those under individual earthquakes and winds. In addition to the responses of the frame such as the floor displacement and acceleration, the damage of BRBs in terms of the damage index, the energy absorption, the plastic strain energy, and the maximum and cumulative ductility factor are evaluated. It is observed that the BRB’s fatigue life under multi-hazard scenarios is a multi-criteria issue that requires more precise investigation. Moreover, the overall building’s performance and BRB’s cumulative damage induced by the sequence of events in the design life of the building is significantly larger than that under an individual event.
Solving the Dynamic Weapon Target Assignment Problem by an Improved Multiobjective Particle Swarm Optimization Algorithm
Authors: Kong Lingren , Wang Jianzhong , Zhao Peng
Published: October 2021

Dynamic weapon target assignment (DWTA) is an effective method to solve the multi-stage battlefield fire optimization problem, which can reflect the actual combat scenario better than static weapon target assignment (SWTA). In this paper, a meaningful and effective DWTA model is established, which contains two practical and conflicting objectives, namely, maximizing combat benefits and minimizing weapon costs. Moreover, the model contains limited resource constraints, feasibility constraints and fire transfer constraints. The existence of multi-objective and multi-constraint makes DWTA more complicated. To solve this problem, an improved multiobjective particle swarm optimization algorithm (IMOPSO) is proposed in this paper. Various learning strategies are adopted for the dominated and non-dominated solutions of the algorithm, so that the algorithm can learn and evolve in a targeted manner. In order to solve the problem that the algorithm is easy to fall into local optimum, this paper proposes a search strategy based on simulated binary crossover (SBX) and polynomial mutation (PM), which enables elitist information to be shared among external archive and enhances the exploratory capabilities of IMOPSO. In addition, a dynamic archive maintenance strategy is applied to improve the diversity of non-dominated solutions. Finally, this algorithm is compared with three state-of-the-art multiobjective optimization algorithms, including solving benchmark functions and DWTA model in this article. Experimental results show that IMOPSO has better convergence and distribution than the other three multiobjective optimization algorithms. IMOPSO has obvious advantages in solving multiobjective DWTA problems.
Surface Properties of Silica–MWCNTs/PDMS Composite Coatings Deposited on Plasma Activated Glass Supports
Authors: Chodkowski Michał , Sulym Iryna Ya. , Terpiłowski Konrad , Sternik Dariusz
Published: October 2021

In this paper, we focus on fabrication and physicochemical properties investigations of silica–multiwalled carbon nanotubes/poly(dimethylsiloxane) composite coatings deposited on the glass supports activated by cold plasma. Air or argon was used as the carrier gas in the plasma process. Multiwalled carbon nanotubes were modified with poly(dimethylsiloxane) in order to impart their hydrophobicity. The silica–multiwalled carbon nanotubes/poly(dimethylsiloxane) nanocomposite was synthesized using the sol–gel technique with acid-assisted tetraethyl orthosilicate hydrolysis. The stability and the zeta potential of the obtained suspension were evaluated. Then, the product was dried and used as a filler in another sol–gel process, which led to the coating application via the dip-coating method. The substrates were exposed to the hexamethyldisilazane vapors in order to improve their hydrophobicity. The obtained surfaces were characterized by the wettability measurements and surface free energy determination as well as optical profilometry, scanning electron microscopy, and transmittance measurements. In addition, the thermal analyses of the carbon nanotubes as well as coatings were made. It was found that rough and hydrophobic coatings were obtained with a high transmittance in the visible range. They are characterized by the water contact angle larger than 90 degrees and the transmission at the level of 95%. The X-ray diffraction studies as well as scanning electron microscopy images confirmed the chemical and structural compositions of the coatings. They are thermally stable at the temperature up to 250 °C. Moreover, the thermal analysis showed that the obtained composite material has greater thermal resistance than the pure nanotubes.
Online Active Set-Based Longitudinal and Lateral Model Predictive Tracking Control of Electric Autonomous Driving
Authors: Fan Wenhui , He Hongwen , Lu Bing
Published: October 2021

Autonomous driving is a breakthrough technology in the automobile and transportation fields. The characteristics of planned trajectories and tracking accuracy affect the development of autonomous driving technology. To improve the measurement accuracy of the vehicle state and realise the online application of predictive control algorithm, an online active set-based longitudinal and lateral model predictive tracking control method of autonomous driving is proposed for electric vehicles. Integrated with the vehicle inertial measurement unit (IMU) and global positioning system (GPS) information, a vehicle state estimator is designed based on an extended Kalman filter. Based on the 3-degree-of-freedom vehicle dynamics model and the curvilinear road coordinate system, the longitudinal and lateral errors dimensionality reduction is carried out. A fast-rolling optimisation algorithm for longitudinal and lateral tracking control of autonomous vehicles is designed and implemented based on convex optimisation, online active set theory and QP solver. Finally, the performance of the proposed tracking control method is verified in the reconstructed curve road scene based on real GPS data. The hardware-in-the-loop simulation results show that the proposed MPC controller has apparent advantages compared with the PID-based controller.
Shaking Table Tests to Validate Inelastic Seismic Analysis Method Applicable to Nuclear Metal Components
Authors: Koo Gyeong-Hoi , Ahn Sang-Won , Hwang Jong-Keun , Kim Jong-Sung
Published: October 2021

The main purpose of this study is to perform shaking table tests to validate the inelastic seismic analysis method applicable to pressure-retaining metal components in nuclear power plants (NPPs). To do this, the test mockup was designed and fabricated to be able to describe the hot leg surge line nozzle with a piping system, which is known to be one of the seismically fragile components in nuclear steam supply systems (NSSS). The used input motions are the displacement time histories corresponding to the design floor response spectrum at an elevation of 136 ft in the in-structure building in NPPs. Two earthquake levels are used in this study. One is the design-basis safe shutdown earthquake level (SSE, PGA = 0.3 g) and the other is the beyond-design-basis earthquake level (BDBE, PGA = 0.6 g), which is linearly scaled from the SSE level. To measure the inelastic strain responses, five strain gauges were attached at the expected critical locations in the target nozzle, and three accelerometers were installed at the shaking table and piping system to measure the dynamic responses. From the results of the shaking table tests, it was found that the plastic strain response at the target nozzle and the acceleration response at the piping system were not amplified by as much as two times the input earthquake level because the plastic behavior in the piping system significantly contributed to energy dissipation during the seismic events. To simulate the test results, elastoplastic seismic analyses with the well-known Chaboche kinematic hardening model and the Voce isotropic hardening model for Type 316 stainless steel were carried out, and the results of the principal strain and the acceleration responses were compared with the test results. From the comparison, it was found that the inelastic seismic analysis method can give very reasonable results when the earthquake level is large enough to invoke plastic behavior in nuclear metal components.
A Robot-Assisted Large-Scale Inspection of Wind Turbine Blades in Manufacturing Using an Autonomous Mobile Manipulator
Authors: Engemann Heiko , Cönen Patrick , Dawar Harshal , Du Shengzhi , Kallweit Stephan
Published: October 2021

Wind energy represents the dominant share of renewable energies. The rotor blades of a wind turbine are typically made from composite material, which withstands high forces during rotation. The huge dimensions of the rotor blades complicate the inspection processes in manufacturing. The automation of inspection processes has a great potential to increase the overall productivity and to create a consistent reliable database for each individual rotor blade. The focus of this paper is set on the process of rotor blade inspection automation by utilizing an autonomous mobile manipulator. The main innovations include a novel path planning strategy for zone-based navigation, which enables an intuitive right-hand or left-hand driving behavior in a shared human–robot workspace. In addition, we introduce a new method for surface orthogonal motion planning in connection with large-scale structures. An overall execution strategy controls the navigation and manipulation processes of the long-running inspection task. The implemented concepts are evaluated in simulation and applied in a real-use case including the tip of a rotor blade form.
Research on Computational Method of Supersonic Inlet/Isolator Internal Flow
Authors: Liu Zhuoran , Wang Caizheng , Zhang Ke , Zhao Zhuo , Xie Zhifeng
Published: October 2021

In this research, a CFD solver is developed for solving the 2D/3D compressible flow problem: the finite volume method based on multi-block structural grids is used to solve the compressible Reynolds averaged Navier–Stokes equations (RANS). Included in the methodology are multiple high-order reconstruction schemes, such as the 3rd-order MUSCL (Monotone Upstreamcentered Schemes for Conservation Laws), 5th-order WENO (Weight Essentially Non-Oscillatory), and 5th-order MP (Monotonicity-Preserving) schemes. Of the variety of turbulence models that are embedded, this solver is mainly based on the shear stress transport model (SST), which is compatible with OpenMP/MPI parallel algorithms. This research uses the CFD solver to conduct steady-state flow simulation for a two-dimensional supersonic inlet/isolator, incorporating these high-precision reconstruction schemes to accurately capture the shock wave/expansion wave interaction and shock wave/turbulent boundary layer interaction (SWTBLI), among other effects. By comparing the 2D/3D computation results of the same inlet configuration, it is found that the 3D effects of the side wall cannot be ignored due to the existing strong lateral flow near the corner. To obtain a more refined turbulence simulation, the commercial software ANSYS Fluent 18.0 is used to carry out the detached eddy simulation (DES) and the large eddy simulation (LES) of the same supersonic inlet, so as to reveal the flow details near the separation area and boundary layers.
Influence of Structural Stiffness and Loss Factor on Railroad Vehicle Comfort
Authors: Pintado Publio , Ramiro Carmen , Palomares Eduardo , Morales Angel L. , Nieto Antonio J. , Chicharro Jose M.
Published: October 2021

This paper presents a new formulation for analyzing a beam on elastic supports traveling on irregular profiles. The model is a first approximation of a passenger railway vehicle car body. The main difference with previous works is the use of a complex modulus to represent structural damping rather than relying on equivalent viscous terms. The formulation groups rigid body modes with flexible modes and proposes a matrix form that is easy to interpret and solve in the frequency domain. Comfort indexes are readily obtained from weighted response spectral densities. The model is used to assess the influence of structural damping and stiffness on comfort. It will be shown that the evolution of comfort with stiffness is non-monotonic and, therefore, comfort does not always improve as stiffness increases.
Webcam Eye Tracking for Monitoring Visual Attention in Hypothetical Online Shopping Tasks
Authors: Schröter Iris , Grillo Nico Rolf , Limpak Margarethe Kristine , Mestiri Bilel , Osthold Benedikt , Sebti Fourat , Mergenthaler Marcus
Published: October 2021

Online retailers are challenged to present their products in an appropriate way to attract customers’ attention. To test the impact of product presentation features on customers’ visual attention, webcam eye tracking might be an alternative to infrared eye tracking, especially in situations where face-to-face contact is difficult. The aim of this study was to examine whether webcam eye tracking is suitable for investigating the influence of certain exogenous factors on customers’ visual attention when visiting online clothing shops. For this purpose, screenshots of two websites of two well-known online clothing retailers were used as stimuli. Linear regression analyses were conducted to determine the influence of the spatial position and the presence of a human model on the percentage of participants visiting a product depiction. The results show that products presented by human models and located in the upper middle area of a website were visited by more participants. From this, we were able to derive recommendations for optimising product presentation in online clothing shops. Our results fit well with those of other studies on visual attention conducted with infrared eye tracking, suggesting that webcam eye tracking could be an alternative to infrared eye tracking, at least for similar research questions.
Modelling Spray Pressure Effects on Droplet Size Distribution from Agricultural Nozzles
Authors: Cerruto Emanuele , Manetto Giuseppe , Papa Rita , Longo Domenico
Published: October 2021

For spray applications, drop size is the most important feature as it affects all aspects of a phytosanitary treatment: biological efficacy, environmental pollution, and operator safety. In turn, drop size distribution depends on nozzle type, liquid properties, and working pressure. In this research, three nozzles were studied under ordinary working conditions and the effect of pressure on drop size distribution was assessed. The nozzles under test, all from Albuz (France), were an orange hollow cone nozzle ATR 80 (European color code), an air induction flat spray nozzle AVI 11003, and an air induction hollow cone nozzle TVI 8002. The ATR 80 and the TVI 8002 nozzles were tested at four pressure values: 0.3, 0.5, 1.0, and 1.5 MPa; the AVI 11003 nozzle was tested at 0.3 and 0.5 MPa. The drop size measurement technique was based on the liquid immersion method by using a custom-made test bench; spray quality parameters were computed by means of suitable functions written in R language. Results showed that an increase in working pressure caused an increase in drop pulverization regardless of the type of nozzle, and drop pulverization was higher for the turbulence nozzle than for the two air induction nozzles. Based on skewness and kurtosis values, the theoretical gamma distribution was the most adapt to fit the experimental data. The scale parameter showed a decreasing trend with the increase in the pressure, a clear index of higher drop pulverization.
Ternion: An Autonomous Model for Fake News Detection
Authors: Islam Noman , Shaikh Asadullah , Qaiser Asma , Asiri Yousef , Almakdi Sultan , Sulaiman Adel , Moazzam Verdah , Babar Syeda Aiman
Published: October 2021

In recent years, the consumption of social media content to keep up with global news and to verify its authenticity has become a considerable challenge. Social media enables us to easily access news anywhere, anytime, but it also gives rise to the spread of fake news, thereby delivering false information. This also has a negative impact on society. Therefore, it is necessary to determine whether or not news spreading over social media is real. This will allow for confusion among social media users to be avoided, and it is important in ensuring positive social development. This paper proposes a novel solution by detecting the authenticity of news through natural language processing techniques. Specifically, this paper proposes a novel scheme comprising three steps, namely, stance detection, author credibility verification, and machine learning-based classification, to verify the authenticity of news. In the last stage of the proposed pipeline, several machine learning techniques are applied, such as decision trees, random forest, logistic regression, and support vector machine (SVM) algorithms. For this study, the fake news dataset was taken from Kaggle. The experimental results show an accuracy of 93.15%, precision of 92.65%, recall of 95.71%, and F1-score of 94.15% for the support vector machine algorithm. The SVM is better than the second best classifier, i.e., logistic regression, by 6.82%.
Spatial-Temporal Characteristics of Agricultural Greenhouse Gases Emissions of the Main Stream Area of the Yellow River Basin in Gansu, China
Authors: Pu Lili , Chen Xingpeng , Lu Chengpeng , Jiang Li , Ma Binbin , Yang Xuedi
Published: October 2021

In 2021, The People’s Republic of China proposed goals for peaking carbon dioxide emissions before 2030 and carbon neutrality before 2060, in the 15 counties (districts) of the Main Stream Area of the Yellow River Basin in Gansu that plays an important role in ecological protection and green development. Next the CO2 equivalents were converted according to the IPCC2 standard, the total agricultural GHG emissions was calculated, the relationship with the agricultural output value was analyzed, and the discretization of the space was analyzed by the coefficient of variation and standard deviation. Firstly, the total agricultural GHG emissions in 15 counties (districts) of the Main Stream Area of the Yellow River Basin increased 55.54% in 2000–2019, and 2.35% annually, roughly divided into three stages: the rapid growth period (2000–2008), the slow decline period (2009–2014) and the rapid decline period (2015–2019). The economic efficiency is significantly improved, with an average annual decline of 6.49%, roughly divided into three stages: the slow-descent stage (2000–2004), the period of slow-growth stage (2005–2008) and the period of fast-decline (2009–2019). Secondly, based on the characteristics of the total GHG emissions, Maqu County has the largest GHG emissions increase, from 26.8842 kt in 2000 to 38.9603 kt, in 2019, an increase of 44.92%, while the smallest GHG emissions, in Anning District, decreased 87.33% from 111 t in 2000 to 14.1 t in 2019; In the rate of increase in the total GHG emissions, Dongxiang County had the largest rate of increase from 2000 to 2019, an increase of 160.28% and an average annual increase of 4.90%. The smallest rate of decrease in GHG emissions was seen in Chengguan District, where they decreased 92.11% from 2000 to 2019, an average annual decrease of 11.93%. The characteristics of agricultural GHG emissions intensity is a significant declining trending and agricultural production efficiency has been significantly improved. Finally, to provide a basis for the formulation of differentiated agricultural energy conservation and emissions reduction policies, reduce agricultural GHG emissions intensity and reduce the use efficiency of resources by formulating differentiated emission targets, tasks and incentive measures.
Spatial and Temporal Distributions of Air Pollutants in Nanchang, Southeast China during 2017–2020
Authors: Wang Xiaoman , Liu Min , Luo Li , Chen Xi , Zhang Yongyun , Zhang Haoran , Yang Shudi , Li Yuxiao
Published: October 2021

In response to COVID-19 in December 2019, China imposed a strict lockdown for the following two months, which led to an unprecedented reduction in industrial activities and transportation. However, haze pollution was still recorded in many Chinese cities during the lockdown period. To explore temporal and spatial variations in urban haze pollution, concentrations of air pollutants (PM2.5, PM10, SO2, CO, NO, NO2, and O3) from April 2017 to March 2020 were observed at 23 monitoring stations throughout Nanchang City (including one industrial site, sixteen urban central sites, two mountain sites, and four suburban sites). Overall, the highest concentrations of PM2.5, PM10, and SO2 were observed at industrial sites and the highest CO and NOx (NO and NO2) concentrations were recorded at urban sites. The air pollutants at mountain sites all showed the lowest concentrations, which indicated that anthropogenic activities are largely responsible for air pollutants. Concentrations of PM2.5, PM10, CO, NO, and NO2 showed similar season trends, that is, the highest levels in winter and lowest concentrations in summer, but an opposite season pattern for O3. Except for a sharply dropping pattern from January to May 2018, there were no seasonal patterns for SO2 concentration in all the observed sites. Daily PM2.5, PM10, CO, NOx, and SO2 concentrations showed a peak during the morning commute, which indicated the influences of anthropogenic activities on PM2.5, PM10, CO, NOx, and SO2. PM2.5, PM10, NOx, and CO concentrations at industrial, urban, and suburban sites were higher during nighttime than during daytime, but they showed the opposite pattern at mountain sites. In addition, PM2.5, PM10, CO, and NOx concentrations were lower during the lockdown period (D2) than those before the lockdown (B1). After the lockdown was lifted (A3), PM2.5, PM10, CO, and NOx concentrations showed a slowly increasing trend. However, O3 concentrations continuously increased from B1 to A3.
Aerosol Properties within and above the Planetary Boundary Layer across the Korean Peninsula during December 2016
Authors: Jung Eunsil , Seo Seongkyu , Chang Ki-Ho , Yum Seong-Soo , Heo Bok-Haeng
Published: October 2021

During December 2016, airborne aerosol measurements were taken at multiple heights across the Korean Peninsula to examine the vertical properties of aerosols. This study showed that aerosols above the planetary boundary layer (PBL) show similar concentrations and particle size distributions (PSDs), regardless of the relative locations in Korea. On the other hand, aerosols within the PBL differ depending on the geographical location, origin and path of the air mass. The concentrations are the highest in Seoul, followed by Gangneung, East Sea and the Yellow Sea. The known east–west aerosol gradient did not appear and the reasons are discussed in this paper. The study further shows that the aerosols of upwind regions affect the aerosols above the PBL, whereas aerosols in the PBL are affected by local sources and atmospheric conditions in addition to aerosols of upwind areas.
Warburg Effect, Glutamine, Succinate, Alanine, When Oxygen Matters
Authors: Bouillaud Frédéric , Hammad Noureddine , Schwartz Laurent
Published: October 2021

Cellular bioenergetics requires an intense ATP turnover that is increased further by hypermetabolic states caused by cancer growth or inflammation. Both are associated with metabolic alterations and, notably, enhancement of the Warburg effect (also known as aerobic glycolysis) of poor efficiency with regard to glucose consumption when compared to mitochondrial respiration. Therefore, beside this efficiency issue, other properties of these two pathways should be considered to explain this paradox: (1) biosynthesis, for this only indirect effect should be considered, since lactate release competes with biosynthetic pathways in the use of glucose; (2) ATP production, although inefficient, glycolysis shows other advantages when compared to mitochondrial respiration and lactate release may therefore reflect that the glycolytic flux is higher than required to feed mitochondria with pyruvate and glycolytic NADH; (3) Oxygen supply becomes critical under hypermetabolic conditions, and the ATP/O2 ratio quantifies the efficiency of oxygen use to regenerate ATP, although aerobic metabolism remains intense the participation of anaerobic metabolisms (lactic fermentation or succinate generation) could greatly increase ATP/O2 ratio; (4) time and space constraints would explain that anaerobic metabolism is required while the general metabolism appears oxidative; and (5) active repression of respiration by glycolytic intermediates, which could ensure optimization of glucose and oxygen use.
Characterizations of Hamster Retina as a Model for Studies of Retinal Cholesterol Homeostasis
Authors: El-Darzi Nicole , Mast Natalia , Dailey Brian , Denker John , Li Yong , Vance Joseph , Pikuleva Irina A.
Published: October 2021

Cholesterol homeostasis in the retina, a sensory organ in the back of the eye, has been studied in mice but not hamsters, despite the latter being more similar to humans than mice with respect to their whole-body cholesterol maintenance. The goal of this study was to begin to assess hamster retina and conduct initial interspecies comparisons. First, young (3-month old) and mature (6-month old) Syrian (golden) hamsters were compared with 3- and 6-month old mice for ocular biometrics and retinal appearance on optical coherence tomography and fluorescein angiography. Of the 30 evaluated hamsters, seven had retinal structural abnormalities and all had increased permeability of retinal blood vessels. However, hamsters did not carry the mutations causing retinal degenerations 1 and 8, had normal blood glucose levels, and only slightly elevated hemoglobin A1c content. Cholesterol and six other sterols were quantified in hamster retina and compared with sterol profiles in mouse and human retina. These comparisons suggested that cholesterol turnover is much higher in younger than mature hamster retina, and that mature hamster and human retinas share similarities in the ratios of cholesterol metabolites to cholesterol. This study supports further investigations of cholesterol maintenance in hamster retina.
DNA Double-Strand Breaks Induced in Human Cells by Twelve Metallic Species: Quantitative Inter-Comparisons and Influence of the ATM Protein
Authors: Viau Muriel , Sonzogni Laurène , Ferlazzo Mélanie L. , Berthel Elise , Pereira Sandrine , Bodgi Larry , Granzotto Adeline , Devic Clément , Fervers Béatrice , Charlet Laurent , Foray Nicolas
Published: October 2021

Despite a considerable amount of data, the molecular and cellular bases of the toxicity due to metal exposure remain unknown. Recent mechanistic models from radiobiology have emerged, pointing out that the radiation-induced nucleo-shuttling of the ATM protein (RIANS) initiates the recognition and the repair of DNA double-strand breaks (DSB) and the final response to genotoxic stress. In order to document the role of ATM-dependent DSB repair and signalling after metal exposure, we applied twelve different metal species representing nine elements (Al, Cu, Zn Ni, Pd, Cd, Pb, Cr, and Fe) to human skin, mammary, and brain cells. Our findings suggest that metals may directly or indirectly induce DSB at a rate that depends on the metal properties and concentration, and tissue type. At specific metal concentration ranges, the nucleo-shuttling of ATM can be delayed which impairs DSB recognition and repair and contributes to toxicity and carcinogenicity. Interestingly, as observed after low doses of ionizing radiation, some phenomena equivalent to the biological response observed at high metal concentrations may occur at lower concentrations. A general mechanistic model of the biological response to metal exposure based on the nucleo-shuttling of ATM is proposed to describe the metal-induced stress response and to define quantitative endpoints for toxicity and carcinogenicity.
Confounders in Identification and Analysis of Inflammatory Biomarkers in Cardiovascular Diseases
Authors: Ain Qurrat Ul , Sarfraz Mehak , Prasesti Gayuk Kalih , Dewi Triwedya Indra , Kurniati Neng Fisheri
Published: October 2021

Proinflammatory biomarkers have been increasingly used in epidemiologic and intervention studies over the past decades to evaluate and identify an association of systemic inflammation with cardiovascular diseases. Although there is a strong correlation between the elevated level of inflammatory biomarkers and the pathology of various cardiovascular diseases, the mechanisms of the underlying cause are unclear. Identification of pro-inflammatory biomarkers such as cytokines, chemokines, acute phase proteins, and other soluble immune factors can help in the early diagnosis of disease. The presence of certain confounding factors such as variations in age, sex, socio-economic status, body mass index, medication and other substance use, and medical illness, as well as inconsistencies in methodological practices such as sample collection, assaying, and data cleaning and transformation, may contribute to variations in results. The purpose of the review is to identify and summarize the effect of demographic factors, epidemiological factors, medication use, and analytical and pre-analytical factors with a panel of inflammatory biomarkers CRP, IL-1b, IL-6, TNFa, and the soluble TNF receptors on the concentration of these inflammatory biomarkers in serum.
Fission Yeast TORC2 Signaling Pathway Ensures Cell Proliferation under Glucose-Limited, Nitrogen-Replete Conditions
Authors: Toyoda Yusuke , Saitoh Shigeaki
Published: October 2021

Target of rapamycin (TOR) kinases form two distinct complexes, TORC1 and TORC2, which are evolutionarily conserved among eukaryotes. These complexes control intracellular biochemical processes in response to changes in extracellular nutrient conditions. Previous studies using the fission yeast, Schizosaccharomyces pombe, showed that the TORC2 signaling pathway, which is essential for cell proliferation under glucose-limited conditions, ensures cell-surface localization of a high-affinity hexose transporter, Ght5, by downregulating its endocytosis. The TORC2 signaling pathway retains Ght5 on the cell surface, depending on the presence of nitrogen sources in medium. Ght5 is transported to vacuoles upon nitrogen starvation. In this review, we discuss the molecular mechanisms underlying this regulation to cope with nutritional stress, a response which may be conserved from yeasts to mammals.
Extracellular Calcium Influx Pathways in Astrocyte Calcium Microdomain Physiology
Authors: Ahmadpour Noushin , Kantroo Meher , Stobart Jillian L.
Published: October 2021

Astrocytes are complex glial cells that play many essential roles in the brain, including the fine-tuning of synaptic activity and blood flow. These roles are linked to fluctuations in intracellular Ca2+ within astrocytes. Recent advances in imaging techniques have identified localized Ca2+ transients within the fine processes of the astrocytic structure, which we term microdomain Ca2+ events. These Ca2+ transients are very diverse and occur under different conditions, including in the presence or absence of surrounding circuit activity. This complexity suggests that different signalling mechanisms mediate microdomain events which may then encode specific astrocyte functions from the modulation of synapses up to brain circuits and behaviour. Several recent studies have shown that a subset of astrocyte microdomain Ca2+ events occur rapidly following local neuronal circuit activity. In this review, we consider the physiological relevance of microdomain astrocyte Ca2+ signalling within brain circuits and outline possible pathways of extracellular Ca2+ influx through ionotropic receptors and other Ca2+ ion channels, which may contribute to astrocyte microdomain events with potentially fast dynamics.
The Role of the C-Terminal Lysine of S100P in S100P-Induced Cell Migration and Metastasis
Authors: Ismail Thamir M. , Gross Stephane R. , Lancaster Tara , Rudland Philip S. , Barraclough Roger
Published: October 2021

S100P protein is a potent inducer of metastasis in a model system, and its presence in cancer cells of patients is strongly associated with their reduced survival times. A well-established Furth Wistar rat metastasis model system, methods for measuring cell migration, and specific inhibitors were used to study pathways of motility-driven metastasis. Cells expressing C-terminal mutant S100P proteins display markedly-reduced S100P-driven metastasis in vivo and cell migration in vitro. These cells fail to display the low focal adhesion numbers observed in cells expressing wild-type S100P, and the mutant S100P proteins exhibit reduced biochemical interaction with non-muscle myosin heavy chain isoform IIA in vitro. Extracellular inhibitors of the S100P-dependent plasminogen activation pathway reduce, but only in part, wild-type S100P-dependent cell migration; they are without effect on S100P-negative cells or cells expressing C-terminal mutant S100P proteins and have no effect on the numbers of focal adhesions. Recombinant wild-type S100P protein, added extracellularly to S100P-negative cells, stimulates cell migration, which is abolished by these inhibitors. The results identify at least two S100P-dependent pathways of migration, one cell surface and the other intracellularly-linked, and identify its C-terminal lysine as a target for inhibiting multiple migration-promoting activities of S100P protein and S100P-driven metastasis.
Protein Unfolding: Denaturant vs. Force
Authors: Kelly Colleen , Gage Matthew J.
Published: October 2021

While protein refolding has been studied for over 50 years since the pioneering work of Christian Anfinsen, there have been a limited number of studies correlating results between chemical, thermal, and mechanical unfolding. The limited knowledge of the relationship between these processes makes it challenging to compare results between studies if different refolding methods were applied. Our current work compares the energetic barriers and folding rates derived from chemical, thermal, and mechanical experiments using an immunoglobulin-like domain from the muscle protein titin as a model system. This domain, I83, has high solubility and low stability relative to other Ig domains in titin, though its stability can be modulated by calcium. Our experiments demonstrated that the free energy of refolding was equivalent with all three techniques, but the refolding rates exhibited differences, with mechanical refolding having slightly faster rates. This suggests that results from equilibrium-based measurements can be compared directly but care should be given comparing refolding kinetics derived from refolding experiments that used different unfolding methods.
Possible Role of Cytochrome P450 1B1 in the Mechanism of Gemcitabine Resistance in Pancreatic Cancer
Authors: Yada Erica , Kasajima Rika , Niida Atsushi , Imoto Seiya , Miyano Satoru , Miyagi Yohei , Sasada Tetsuro , Wada Satoshi
Published: October 2021

Patient-derived xenograft models reportedly represent original tumor morphology and gene mutation profiles. In addition, patient-derived xenografts are expected to recapitulate the parental tumor drug responses. In this study, we analyzed the pathways involved in gemcitabine resistance using patient-derived xenograft models of pancreatic cancer. The patient-derived xenograft models were established using samples from patients with pancreatic cancer. The models were treated with gemcitabine to better understand the mechanism of resistance to this anti-cancer drug. We performed comparative gene analysis through the next-generation sequencing of tumor tissues from gemcitabine-treated or non-treated patient-derived xenograft mice and gene set enrichment analysis to analyze mRNA profiling data. Pathway analysis of gemcitabine-treated patient-derived xenografts disclosed the upregulation of multiple gene sets and identified several specific gene pathways that could potentially be related to gemcitabine resistance in pancreatic cancer. Further, we conducted an in vitro analysis to validate these results. The mRNA expression of cytochrome P450 1B1 and cytochrome P450 2A6 was upregulated in a concentration-dependent manner following gemcitabine treatment. Moreover, the sensitivity to gemcitabine increased, and viable cells were decreased by the cytochrome P450 1B1 inhibitor, indicating that the cytochrome P450 1B1 pathway may be related to gemcitabine resistance in pancreatic cancer.
Bilateral Adrenal Hyperplasia: Pathogenesis and Treatment
Authors: Chevalier Benjamin , Vantyghem Marie-Christine , Espiard Stéphanie
Published: October 2021

Bilateral adrenal hyperplasia is a rare cause of Cushing’s syndrome. Micronodular adrenal hyperplasia, including the primary pigmented micronodular adrenal dysplasia (PPNAD) and the isolated micronodular adrenal hyperplasia (iMAD), can be distinguished from the primary bilateral macronodular adrenal hyperplasia (PBMAH) according to the size of the nodules. They both lead to overt or subclinical CS. In the latter case, PPNAD is usually diagnosed after a systematic screening in patients presenting with Carney complex, while for PBMAH, the diagnosis is often incidental on imaging. Identification of causal genes and genetic counseling also help in the diagnoses. This review discusses the last decades’ findings on genetic and molecular causes of bilateral adrenal hyperplasia, including the several mechanisms altering the PKA pathway, the recent discovery of ARMC5, and the role of the adrenal paracrine regulation. Finally, the treatment of bilateral adrenal hyperplasia will be discussed, focusing on current data on unilateral adrenalectomy.
T-Cadherin and the Ratio of Its Ligands as Predictors of Carotid Atherosclerosis: A Pilot Study
Authors: Balatskiy Alexander , Teterina Marina , Pisaryuk Alexandra , Balabanenko Irina , Kadrev Alexey , Tishuk Anastasia , Balatskaya Maria , Samokhodskaya Larisa , Boytsov Sergey , Kalinina Natalia , Tkachuk Vsevolod
Published: October 2021

In the cardiovascular system, atherogenic low-density lipoproteins (LDL) and the protective hormone adiponectin bind to the same receptor, T-cadherin. In this study, we tested the hypothesis that the ratio of circulating LDL to high-molecular weight (HMW) adiponectin could predict the development of atherosclerosis. Using enzyme-linked immunosorbent assay, we measured the level of circulating HMW adiponectin in the blood of donors together with ultrasound measuring of intima-media thickness (IMT) of carotid arteries. Single-nucleotide polymorphisms in the T-cadherin gene were identified using polymerase chain reaction. We found that carotid artery IMT is inversely correlated with the level of HMW in male subjects. We also found that the G allele of rs12444338 SNP in the T-cadherin gene correlates with a lower level of circulating T-cadherin and thinner IMT and therefore could be considered as an atheroprotective genotype. Despite our data, we could not provide direct evidence for the initial study hypothesis. However, we did uncover an important correlation between circulating T-cadherin and thinner carotid IMT.
Rapid COVID-19 Molecular Diagnostic System Using Virus Enrichment Platform
Authors: Jang Yoon Ok , Lee Hyo Joo , Koo Bonhan , Cha Hye-Hee , Kwon Ji-Soo , Kim Ji Yeun , Kim Myoung Gyu , Kim Hyun Soo , Kim Sung-Han , Shin Yong
Published: October 2021

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV)-2, is rapidly spreading and severely straining the capacities of public health communities and systems around the world. Therefore, accurate, rapid, and robust diagnostic tests for COVID-19 are crucial to prevent further spread of the infection, alleviate the burden on healthcare and diagnostic facilities, and ensure timely therapeutic intervention. To date, several detection methods based on nucleic acid amplification have been developed for the rapid and accurate detection of SARS-CoV-2. Despite the myriad of advancements in the detection methods for SARS-CoV-2, rapid sample preparation methods for RNA extraction from viruses have rarely been explored. Here, we report a rapid COVID-19 molecular diagnostic system that combines a self-powered sample preparation assay and loop-mediated isothermal amplification (LAMP) based naked-eye detection method for the rapid and sensitive detection of SARS-CoV-2. The self-powered sample preparation assay with a hydrophilic polyvinylidene fluoride filter and dimethyl pimelimidate can be operated by hand, without the use of any sophisticated instrumentation, similar to the reverse transcription (RT)-LAMP-based lateral flow assay for the naked-eye detection of SARS-CoV-2. The COVID-19 molecular diagnostic system enriches the virus population, extracts and amplifies the target RNA, and detects SARS-CoV-2 within 60 min. We validated the accuracy of the system by using 23 clinical nasopharyngeal specimens. We envision that this proposed system will enable simple, facile, efficient, and inexpensive diagnosis of COVID-19 at home and the clinic as a pre-screening platform to reduce the burden on the medical staff in this pandemic era.