bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification and Characterization of Quorum-Quenching Activity of N-Acylhomoserine Lactonase from Coagulase-Negative Staphylococci
Authors: Morohoshi Tomohiro , Kamimura Yaoki , Someya Nobutaka
Published: August 2020

N-Acylhomoserine lactones (AHLs) are used as quorum-sensing signals in Gram-negative bacteria. Many genes encoding AHL-degrading enzymes have been cloned and characterized in various microorganisms. Coagulase-negative staphylococci (CNS) are present on the skin of animals and are considered low-virulent species. The AHL-lactonase gene homologue, ahlS, was present in the genomes of the CNS strains Staphylococcus carnosus, Staphylococcus haemolyticus, Staphylococcus saprophyticus, and Staphylococcus sciuri. We cloned the candidate ahlS homologue from six CNS strains into the pBBR1MCS5 vector. AhlS from the CNS strains showed a higher degrading activity against AHLs with short acyl chains compared to those with long acyl chains. AhlS from S. sciuri was expressed and purified as a maltose-binding protein (MBP) fusion. Pseudomonas aeruginosa is an opportunistic pathogen that regulates several virulence factors such as elastase and pyocyanin by quorum-sensing systems. When MBP-AhlS was added to the culture of P. aeruginosa PAO1, pyocyanin production and elastase activity were substantially reduced compared to those in untreated PAO1. These results demonstrate that the AHL-degrading activity of AhlS from the CNS strains can inhibit quorum sensing in P. aeruginosa PAO1.
Eukarion-134 Attenuates Endoplasmic Reticulum Stress-Induced Mitochondrial Dysfunction in Human Skeletal Muscle Cells
Authors: Thoma Anastasia , Lyon Max , Al-Shanti Nasser , Nye Gareth A. , Cooper Robert G. , Lightfoot Adam P.
Published: August 2020

Maladaptive endoplasmic reticulum (ER) stress is associated with modified reactive oxygen species (ROS) generation and mitochondrial abnormalities; and is postulated as a potential mechanism involved in muscle weakness in myositis, an acquired autoimmune neuromuscular disease. This study investigates the impact of ROS generation in an in vitro model of ER stress in skeletal muscle, using the ER stress inducer tunicamycin (24 h) in the presence or absence of a superoxide dismutase/catalase mimetic Eukarion (EUK)-134. Tunicamycin induced maladaptive ER stress, which was mitigated by EUK-134 at the transcriptional level. ER stress promoted mitochondrial dysfunction, described by substantial loss of mitochondrial membrane potential, as well as a reduction in respiratory control ratio, reserve capacity, phosphorylating respiration, and coupling efficiency, which was ameliorated by EUK-134. Tunicamycin induced ROS-mediated biogenesis and fusion of mitochondria, which, however, had high propensity of fragmentation, accompanied by upregulated mRNA levels of fission-related markers. Increased cellular ROS generation was observed under ER stress that was prevented by EUK-134, even though no changes in mitochondrial superoxide were noticeable. These findings suggest that targeting ROS generation using EUK-134 can amend aspects of ER stress-induced changes in mitochondrial dynamics and function, and therefore, in instances of chronic ER stress, such as in myositis, quenching ROS generation may be a promising therapy for muscle weakness and dysfunction.
Reduction of Nitrite in Meat Products through the Application of Various Plant-Based Ingredients
Authors: Ferysiuk Karolina , Wójciak Karolina M.
Published: August 2020

Nitrite is the most commonly applied curing agent in the meat industry, and is known to affect human health. Nitrites impart a better flavor, taste and aroma; preserve the red-pinkish color of the meat; and prevent the risk of bacterial contamination of the cured meat, especially from Clostridium botulinum. Unfortunately, recent research has demonstrated some negative effects of this technique. Certain N-nitroso compounds have been shown to stimulate gastric cancer; therefore, most of the research groups are studying the effects of nitrates and nitrites. In this review, we discuss the various food sources of nitrites and nitrates and their current legal requirements for use in meat products. We also discuss the possible changes that might come up in the regulations, the concerns associated with nitrates and nitrites in meat products, and the use of plant-based nitrite and nitrate substitutes. All these topics will be considered with respect to ensuring a high level of microbiological protection, oxidative stability and acceptable sensory quality (color, taste and smell) in meat products.
Local Phase-Amplitude Joint Correction for Free Surface Velocity of Hopkinson Pressure Bar
Authors: Yang Jun , He Junhua , Zhang Dezhi , Xu Haibin , Shi Guokai , Zhang Min , Liu Wenxiang , Zhang Yang
Published: August 2020

The Hopkinson pressure bar is widely used to measure the reflected pressure of blast waves over a short distance. However, dispersion effects will occur when the elastic stress waves propagate in the pressure bar due to lateral inertia, and there will be errors between the signals obtained from the sensors and the actual loading. For the free surface velocity measured in our system, we developed a local phase-amplitude joint correction method to convert the measured velocity into the average reflected pressure of a shock wave at the impact end of the bar, considering factors such as propagation modes of the elastic wave, the frequency components’ time of arrival, velocity variation over the bar axis, and the stress–velocity relationship. Firstly, the Pochhammer–Chree frequency equation is calculated numerically, and the first to fourth orders of phase velocity, group velocity, normalized frequency, and propagation time curves of elastic wave propagation in 35CrMnSiA steel are obtained. Secondly, the phase and amplitude correction formulas for calculating average reflected pressure from center velocity are derived based on the propagation mode of the axial elastic wave in the pressure bar by analyzing the time-frequency combined spectrum obtained by short-time Fourier transform. Thirdly, a local phase-amplitude joint correction algorithm based on propagation mode is proposed in detail. The experimental tests and data analyses are carried out for eight sets of pressure bar. The results show that this method can identify the propagation mode of elastic waves in the bar intuitively and clearly. The first three orders of propagation modes are stimulated in the bar 04, while only the first order of propagation is stimulated in the other eight bars. The local phase-amplitude joint correction algorithm can avoid correcting the component of the non-axial elastic wave. The rising edge of the average stress curve on the impact surface of bar 01 and bar 04 is corrected from 4.13 μs and 4.09 μs to 2.70 μs, respectively.
Ferrite-Loaded Spidron Fractal Loop VHF Antenna for UAV Applications
Authors: Park Won Bin , Park Young-Mi , Hwang Keum Cheol
Published: August 2020

In this letter, an electrically small Spidron fractal loop antenna operating in the VHF band is proposed. The ferrite material, which consists of a nickel-zinc combination, is loaded into inside of the loop antenna to increase the gain of the antenna in the low frequency band. To minimize the magnetic loss of the ferrite in the high frequency band, the amount and configuration of the ferrite are optimized using a genetic algorithm. Through this optimization step, the amount of the ferrite is decreased to 37.5% and the gain of the antenna in the high frequency band is improved. The size of the proposed antenna is 0.0242 × 0.0242 × 0.0051 λL3 at the lowest operating frequency. The proposed antenna was fabricated to verify the performance, and the simulated and measured results are in good agreement. The measured peak gains varied from −31.6 to −1.9 dBi within the measured frequency band. To examine the performance of the proposed antenna mounted on an unmanned aerial vehicle model (UAV), the antenna on a UAV was also simulated and the results were discussed. The simulated realized peak gains of the antenna on the UAV and on flat ground are similar.
Numerical 3D Modeling: Microwave Plasma Torch at Intermediate Pressure
Authors: Shen Qinghao , Huang Run , Xu Zili , Hua Wei
Published: August 2020

This study represents a self-consistent three-dimensional (3D) fluid plasma model coupled with Maxwell equations at an intermediate pressure between 1000 and 5000 Pa. The model was established using the finite element method to analyze the effects of time–space characteristics, which is the variation of plasma parameters with time and the 3D spatial distribution of plasma parameters in the plasma torch at various times. The numerical modeling was demonstrated in three different stages, where the growth of electron density is associated with time. From the distribution characteristics of molecular ions, it can be concluded that they are distributed mainly at the port of the quartz tube of the torch, which is larger than the center of the tube. The density ratio of molecular ion to electron is decreased because of the reduction of pressure and distance, which has been calculated from the port to the center of the quartz tube. The analysis of microwave plasma parameters indicated that intermediate pressure is useful for modeling and plasma source designing, especially for carbon dioxide conversion.
Investigation of Size Effects Due to Different Cooling Rates of As-Quenched Martensite Microstructures in a Low-Alloy Steel
Authors: Graf Marius , Kuntz Matthias , Autenrieth Hermann , Müller Ralf
Published: August 2020

Martensite transformation is a complex mechanism in materials that is classically initiated by a suitable heat treatment. This heat treatment process can be optimized based on a better understanding of the physical mechanisms on the length scale of several prior austenite grains. It is therefore appropriate to consider individual process steps of heat treatment in isolation. The aim of this study is to characterize the microstructural size changes caused by a variation of the cooling rate applied during the quenching process. For this purpose, individual martensitic microstructures from different heat treatments are analyzed using the electron backscatter diffraction (EBSD) method. With special orientation relationships between the parent austenite and martensite, the structure of the prior austenite grains and the close packet plane packets can then be reconstructed. The influence of the heat treatments on these characteristics as well as on the martensite blocks is thus quantified. No significant influence of the quenching rate on the sizes of martensite blocks and packets could be found.
Phytoremediation of TSS, NH3-N and COD from Sewage Wastewater by Lemna minor L., Salvinia minima, Ipomea aquatica and Centella asiatica
Authors: Abdul Aziz Nur Izzah Hamna , Mohd Hanafiah Marlia , Halim Nasrun Hisyam , Fidri Putri Amylin Sofea
Published: August 2020

The rapid growth of industries has resulted in wastewater generation containing different organic and chemical substances channeled into the water body. This causes the arising of water pollution issues in many regions. The phytoremediation method was introduced in the process of treating water pollution as it is low cost and environmentally friendly. Lemna minor, Salvinia minima, Ipomoea aquatica and Centella asiatica were chosen in this study because they have tolerance to various pollution conditions and are able to remove organic pollutants and heavy metals. The objectives of this study were to determine the water quality before and after treatment, to determine the rate of reduction in total suspended solids (TSS), ammoniacal nitrogen (NH3-N), and chemical oxygen demand (COD) in sewage water through the phytoremediation method and to assess the effectiveness of the plants in the phytoremediation of sewage wastewater. It was found that, Lemna minor, Salvinia minima, Ipomoea aquatica and Centella asiatica were able to reduce TSS by 50.8%, 77.6%, 85.6% and 67.6%, respectively; NH3-N by 80.4%, 89.9, 97.3% and 79.1%, respectively; and COD by 75%, 82%, 44.8% and 36.46%, respectively. In this study, it was found that sewage wastewater treatment using Ipomoea aquatica was more efficient in reducing NH3-N and Salvinia minima was more efficient in reducing TSS and COD values.
Measuring Gait-Event-Related Brain Potentials (gERPs) during Instructed and Spontaneous Treadmill Walking: Technical Solutions and Automated Classification through Artificial Neural Networks
Authors: Herbert Cornelia , Munz Michael
Published: August 2020

The investigation of the neural correlates of human gait, as measured by means of non-invasive electroencephalography (EEG), is of central importance for the understanding of human gait and for novel developments in gait rehabilitation. Particularly, gait-event-related brain potentials (gERPs) may provide information about the functional role of cortical brain regions in human gait control. The purpose of this paper is to explore possible experimental and technical solutions for time-sensitive analysis of human gait ERPs during spontaneous and instructed treadmill walking. A solution (hardware/software) for synchronous recording of gait and EEG data was developed, tested and piloted. The solution consists of a custom-made USB synchronization interface, a time-synchronization module, and a data-merging module, allowing the temporal synchronization of recording devices, time-sensitive extraction of gait markers for the analysis of gERPs, and the training of artificial neural networks. In the present manuscript, the hardware and software components were tested with the following devices: A treadmill with an integrated pressure plate for gait analysis (zebris FDM-T) and an Acticap non-wireless 32-channel EEG system (Brain Products GmbH). The usability and validity of the developed solution was investigated in a pilot study (n = 3 healthy participants, n = 3 females, mean age = 22.75 years). The recorded continuous EEG data were segmented into epochs according to the detected gait markers for the analysis of gERPs. Finally, the EEG epochs were used to train a deep learning artificial neural network as classifier of gait phases. The results obtained in this pilot study, although preliminary, support the feasibility of the solution for the application of gait-related EEG analysis.
Relationships between Surface Properties and Snow Adhesion and Its Shedding Mechanisms
Authors: Heil Jamie , Mohammadian Behrouz , Sarayloo Mehdi , Bruns Kevin , Sojoudi Hossein
Published: August 2020

Understanding the mechanisms of snow adhesion to surfaces and its subsequent shedding provides means to search for active and passive methods to mitigate the issues caused by snow accumulation on surfaces. Here, a novel setup is presented to measure the adhesion strength of snow to various surfaces without altering its properties (i.e., liquid water content (LWC) and/or density) during the measurements and to study snow shedding mechanisms. In this setup, a sensor is utilized to ensure constant temperature and liquid water content of snow on test substrates, unlike inclined or centrifugal snow adhesion testing. A snow gun consisting of an internal mixing chamber and ball valves for adjusting air and water flow is designed to form snow with controlled LWC inside a walk-in freezing room with controlled temperatures. We report that snow adheres to surfaces strongly when the LWC is around 20%. We also show that on smooth (i.e., RMS roughness of less than 7.17 μm) and very rough (i.e., RMS roughness of greater than 308.33 μm) surfaces, snow experiences minimal contact with the surface, resulting in low adhesion strength of snow. At the intermediate surface roughness (i.e., RMS of 50 μm with a surface temperature of 0 °C, the contact area between the snow and the surface increases, leading to increased adhesion strength of snow to the substrate. It is also found that an increase in the polar surface energy significantly increases the adhesion strength of wet snow while adhesion strength decreases with an increase in dispersive surface energy. Finally, we show that during shedding, snow experiences complete sliding, compression, or a combination of the two behaviors depending on surface temperature and LWC of the snow. The results of this study suggest pathways for designing surfaces that might reduce snow adhesion strength and facilitate its shedding.
Bonding Behaviors of GFRP/Steel Bonded Joints after Wet–Dry Cyclic and Hygrothermal Curing
Authors: Liu Jie , Guo Tong , Hebdon Matthew H. , Liu Zhongxiang , Wang Libin
Published: August 2020

This paper presents the outcomes of a research program that tested and examined the behaviors of glass fiber-reinforced polymer (GFRP) bonded steel double-strap joints after being cured in a variety of harsh curing conditions. Nineteen specimens were manufactured, cured in an air environment (the reference specimen), treated with different wet–dry cyclic curing or hygrothermal pretreatment, and then tested under quasi-static loading. Based on the experimental studies, mixed failure modes, rather than the cohesive failure of the adhesive, were found in the harsh environmental cured specimens. Additionally, an approximately linear relationship of load–displacement curves was observed for all the GFRP/steel bonded specimens from which the tensile capacities and stiffness were discussed. By analyzing the strain development of the bonded specimens during quasi-static tensile testing, the fracture mechanism analysis focused on the threshold value of the strain curves for different cured specimens. Finally, based on the studies of interfacial fracture energy, Gf, the effects of harsh environmental curing were assessed. The results showed that the failure modes, joint tensile capacities, stiffness, and interfacial fracture energy Gf were highly dependent on the curing conditions, and a significant degradation of bonding performance could be introduced by the investigated harsh environments.
Shaking Table Substructure Testing Based on Three-Variable Control Method with Velocity Positive Feedback
Authors: Xu Guoshan , Wang Zhen , Bao Yintong , Yang Ge , Wu Bin
Published: August 2020

To improve the experimental accuracy and stability of shaking table substructure testing (STST), an explicit central difference method (CDM) and a three-variable control method (TVCM) with velocity positive feedback (VPF) are proposed in this study. First, the explicit CDM is presented for obtaining an improved control accuracy of the boundary conditions between the numerical and experimental substructures of STST. Compared with the traditional CDM, the proposed method can provide explicit control targets for displacement, velocity, and acceleration. Furthermore, a TVCM-VPF is proposed to improve the control stability and accuracy for loading the explicit control targets of displacement, velocity, and acceleration. The effectiveness of the proposed methods is validated by experiments on a three-story frame structure with a tuned liquid damper loaded on an old shaking table originally designed with the traditional displacement control mode. The experimental results show that the proposed explicit CDM works well, and the response rate and control accuracy of the shaking table are significantly improved with the contribution of the TVCM-VPF compared with those of the traditional proportional integral derivative (PID) controller. This indicates the advantage of the proposed TVCM-VPF over the traditional PID for STST. A comparison between the traditional shaking table test and STST shows that when the latter is based on the TVCM-VPF, it exhibits an excellent performance in terms of the stability and accuracy of displacement and an acceptable performance in terms of the acceleration accuracy.
Facile Synthesis of Highly Conductive Vanadium-Doped NiO Film for Transparent Conductive Oxide
Authors: Kotta Ashique , Seo Hyung Kee
Published: August 2020

Metal-oxide-based electrodes play a crucial role in various transparent conductive oxide (TCO) applications. Among the p-type materials, nickel oxide is a promising electrically conductive material due to its good stability, large bandgap, and deep valence band. Here, we display pristine and 3 at.%V-doped NiO synthesized by the solvothermal decomposition method. The properties of both the pristine and 3 at.%V:NiO nanoparticles were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD), Raman spectroscopy, ultraviolet–visible spectroscopy (UV–vis), and X-ray photoelectron spectroscopy (XPS). The film properties were characterized by atomic force microscopy (AFM) and a source meter. Our results suggest that incorporation of vanadium into the NiO lattice significantly improves both electrical conductivity and hole extraction. Also, 3 at.%V:NiO exhibits a lower crystalline size when compared to pristine nickel oxide, which maintains the reduction of surface roughness. These results indicate that vanadium is an excellent dopant for NiO.
Internal Force Analysis of Buried-boring Piles in the Yuanzishan Landslide
Authors: Wang Hao , Lv Zhiying , Zhang Jianwei , Yue Jianwei , Qin Hongyu , Hung Chaoying
Published: August 2020

The Yuanzishan landslide is an unstable slope in Langzhong County, located in northeast Sichuan province, China. The Guangyuan-Nanchong expressway passes through the front edge of the unstable slope, and subgrade excavation has resulted in slope deformation, which threatens the safety of the highway construction. Emergency landslide control requires reduction of the slope disturbance. This study aims to investigate the use of buried-boring piles as a potential method for emergency landslide control. A simplified calculation method was used for the design of the buried-boring piles, according to the limit equilibrium of the soil and the elastic foundation coefficient method. The measured internal force changes of the pile were compared, in order to determine the distribution coefficients of the driving force. A relationship between the driving force of the shared pile ratio and the buried depth ratios was then established. Furthermore, a variety of factors affecting the internal forces of the buried-boring pile and the lateral reaction of the soil were also studied. The results revealed that (1) there was a quadratic relationship between the driving force of the pile-shared ratio and the sliding depth ratios; (2) the maximum bending moment of the pile increased with an increase in the sliding depth ratio of the pile, following a power law relationship; (3) increasing the buried depth of the pile head reduced the influence of the pile diameter on the maximum internal forces; (4) increasing the pile diameter decreased the maximum lateral reaction of the soil. The buried-boring piles can be used in similarly unstable regions for emergency control of deforming slopes.
Demand Analysis of Lubricating Oil in Spur Gear Pairs
Authors: Jia Fuchun , Lei Yulong , Fu Yao , Wang Binyu , Hu Jianlong
Published: August 2020

Theoretical calculation and numerical simulation are used to investigate the lubricating oil demand of spur gears. In accordance with the function of lubricating oil during the meshing process, oil demand is regarded as the superposition of oil for lubrication and cooling. Oil for lubrication is calculated in accordance with meshing and elastohydrodynamic lubrication (EHL) theories. Oil for cooling is obtained from friction heat. The influence of different meshing positions on lubricating oil demand is analysed, and the effects of modulus, tooth number, transmission ratio, input speed and input torque on lubricating oil demand is investigated using a control variate method. Simulation results indicated that oil for lubrication and oil for cooling have two maxima each during a meshing circle. The influences of different gear parameters and working conditions on lubricating oil demand are compared. The results showed that the oil volume for lubrication increases and oil volume for cooling decreases as the modulus, tooth number and transmission ratio of the gear increase, the oil volume for lubrication and oil volume for cooling increases as the input speed and input torque increase.
A Novel Negative Stiffness Amplification System Based Isolation Method for the Vibration Control of Underground Structures
Authors: Chen Qingjun , Wang Yanchao , Zhao Zhipeng
Published: August 2020

Underground structures can be vulnerable during strong earthquakes, and seismic mitigation systems designed for these structures are instrumental in improving multiple aspects of seismic performance. To deal with this problem, a novel isolation system is proposed for underground structures, employing the incorporation of a negative-stiffness amplification system (NSAS) and an isolator. The proposed NSAS consists of the subconfiguration of a spring with positive stiffness in parallel with a dashpot, which is then in series with a negative-stiffness device. The mechanical model and physical realization of the NSAS are presented, based on which the energy-dissipation-enhancement mechanism of NSAS is detailed. On this basis, comprehensive parameter analyses were conducted between the NSAS isolation system and a conventional isolation system. Analysis results showed that the NSAS exhibited a significant energy-dissipation-enhancement effect, in which the series connection of the negative and positive stiffnesses amplified the dashpot’s deformation for enhanced energy-dissipation capacity and efficiency. Compared with a conventional isolator, the NSAS isolation system provided the underground structure with a multiperformance and multilevel mitigation effect, particularly yielding lower responses of displacement and shear forces at the same time. More vibration energy could be dissipated by NSAS, thereby alleviating the energy-dissipation burden of underground structures.
A Topical Category-Aware Neural Text Summarizer
Authors: Kim So-Eon , Kaibalina Nazira , Park Seong-Bae
Published: August 2020

The advent of the sequence-to-sequence model and the attention mechanism has increased the comprehension and readability of automatically generated summaries. However, most previous studies on text summarization have focused on generating or extracting sentences only from an original text, even though every text has a latent topic category. That is, even if a topic category helps improve the summarization quality, there have been no efforts to utilize such information in text summarization. Therefore, this paper proposes a novel topical category-aware neural text summarizer which is differentiated from legacy neural summarizers in that it reflects the topic category of an original text into generating a summary. The proposed summarizer adopts the class activation map (CAM) as topical influence of the words in the original text. Since the CAM excerpts the words relevant to a specific category from the text, it allows the attention mechanism to be influenced by the topic category. As a result, the proposed neural summarizer reflects the topical information of a text as well as the content information into a summary by combining the attention mechanism and CAM. The experiments on The New York Times Annotated Corpus show that the proposed model outperforms the legacy attention-based sequence-to-sequence model, which proves that it is effective at reflecting a topic category into automatic summarization.
Identifying Critical Clusters of Traffic-Loading Events in Recurrent Congested Conditions on a Long-Span Road Bridge
Authors: Micu E. Alexandra , OBrien Eugene J. , Malekjafarian Abdollah , McKinstray Ross , Angus Ewan , Lydon Myra , Catbas F. Necati
Published: August 2020

This paper examines the nature of traffic loading in recurrent congested traffic conditions on a long-span suspension bridge. Traffic flow and percentage of trucks are extracted from image data and a cluster analysis performed to classify the data into four clusters. One cluster (MTHF, medium truck percentage and high flow) is identified that incorporates almost 50% of the hours of traffic data scattered throughout the day. Site-specific load assessment confirms that this MTHF cluster is the most critical for the bridge considered, the Forth Road Bridge in Scotland. For non-recurrent congestion, another cluster (HTLF, high percentage of trucks and low flow) is shown to govern but this finding is highly site-specific, depending on the relative frequency of the different types of congestion. A comparison of the maximum hourly/daily MTHF load effect of the cable force for five notional bridges shows that a 100% increase in the bridge span generates an increase of about 65% in the characteristic load effect.
Building Geometry Simplification for Improving Mesh Quality of Numerical Analysis Model
Authors: Park Gwanyong , Kim Changmin , Lee Minhyung , Choi Changho
Published: August 2020

Numerical analysis, especially the finite volume method (FVM), is one of the primary approaches employed when evaluating a building environment. A complicated geometry can degrade the mesh quality, leading to numerical diffusions and errors. Thus, this study develops and evaluates an automatic building geometry simplification method based on integrating similar surfaces for the geometry of an indoor space. A regression model showed that the complexity of the simplified geometry and its similarity to the original geometry decreased linearly with the threshold of the method. The mesh quality was significantly improved by the simplification. In particular, the maximum skewness decreased exponentially with the threshold of the method. It is expected that the simplification method and regression model presented in this study can be used to quantitatively control the mesh quality.
Reconciling Chord Length Distributions and Area Distributions for Fields of Fractal Cumulus Clouds
Authors: Barron Nicholas R. , Ryan Shawn D. , Heus Thijs
Published: August 2020

While the total cover of broken cloud fields can in principle be obtained from one-dimensional measurements, the cloud size distribution normally differs between two-dimensional (area) and one-dimensional retrieval (chord length) methods. In this study, we use output from high-resolution Large Eddy Simulations to generate a transfer function between the two. We retrieve chord lengths and areas for many clouds, and plot the one as a function of the other, and vice versa. We find that the cloud area distribution conditional on the chord length behaves like a gamma distribution with well-behaved parameters, with a mean μ=1.1L and a shape parameter β=L−0.645. Using this information, we are able to generate a transfer function that can adjust the chord length distribution so that it comes much closer to the cloud area distribution. Our transfer function improves the error in predicting the mean cloud size, and is performs without strong biases for smaller sample sizes. However, we find that the method is still has difficulties in accurately predicting the frequency of occurrence of the largest cloud sizes.
Expanding the Limits of Computer-Assisted Sperm Analysis through the Development of Open Software
Authors: Yániz Jesús , Alquézar-Baeta Carlos , Yagüe-Martínez Jorge , Alastruey-Benedé Jesús , Palacín Inmaculada , Boryshpolets Sergii , Kholodnyy Vitaliy , Gadêlha Hermes , Pérez-Pe Rosaura
Published: August 2020

Computer assisted sperm analysis (CASA) systems can reduce errors occurring in manual analysis. However, commercial CASA systems are frequently not applicable at the forefront of challenging research endeavors. The development of open source software may offer important solutions for researchers working in related areas. Here, we present an example of this, with the development of three new modules for the OpenCASA software (hosted at Github). The first is the Chemotactic Sperm Accumulation Module, a powerful tool for studying sperm chemotactic behavior, analyzing the sperm accumulation in the direct vicinity of the stimuli. This module was validated by comparing fish sperm accumulation, with or without the influence of an attractant. The analysis clearly indicated cell accumulation in the treatment group, while the distribution of sperm was random in the control group. The second is the Sperm Functionality Module, based on the ability to recognize five sperm subpopulations according to their fluorescence patterns associated with the plasma membrane and acrosomal status. The last module is the Sperm Concentration Module, which expands the utilities of OpenCASA. These last two modules were validated, using bull sperm, by comparing them with visual counting by an observer. A high level of correlation was achieved in almost all the data, and a good agreement between both methods was obtained. With these newly developed modules, OpenCASA is consolidated as a powerful free and open-source tool that allows different aspects of sperm quality to be evaluated, with many potential applications for researchers.
Long QT Syndrome Type 2: Emerging Strategies for Correcting Class 2 KCNH2 (hERG) Mutations and Identifying New Patients
Authors: Ono Makoto , Burgess Don E. , Schroder Elizabeth A. , Elayi Claude S. , Anderson Corey L. , January Craig T. , Sun Bin , Immadisetty Kalyan , Kekenes-Huskey Peter M. , Delisle Brian P.
Published: August 2020

Significant advances in our understanding of the molecular mechanisms that cause congenital long QT syndrome (LQTS) have been made. A wide variety of experimental approaches, including heterologous expression of mutant ion channel proteins and the use of inducible pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from LQTS patients offer insights into etiology and new therapeutic strategies. This review briefly discusses the major molecular mechanisms underlying LQTS type 2 (LQT2), which is caused by loss-of-function (LOF) mutations in the KCNH2 gene (also known as the human ether-à-go-go-related gene or hERG). Almost half of suspected LQT2-causing mutations are missense mutations, and functional studies suggest that about 90% of these mutations disrupt the intracellular transport, or trafficking, of the KCNH2-encoded Kv11.1 channel protein to the cell surface membrane. In this review, we discuss emerging strategies that improve the trafficking and functional expression of trafficking-deficient LQT2 Kv11.1 channel proteins to the cell surface membrane and how new insights into the structure of the Kv11.1 channel protein will lead to computational approaches that identify which KCNH2 missense variants confer a high-risk for LQT2.
Functionalizable Antifouling Coatings as Tunable Platforms for the Stress-Driven Manipulation of Living Cell Machinery
Authors: Víšová Ivana , Smolková Barbora , Uzhytchak Mariia , Vrabcová Markéta , Chafai Djamel Eddine , Houska Milan , Pastucha Matěj , Skládal Petr , Farka Zdeněk , Dejneka Alexandr , Vaisocherová-Lísalová Hana
Published: August 2020

Cells are continuously sensing their microenvironment and subsequently respond to different physicochemical cues by the activation or inhibition of different signaling pathways. To study a very complex cellular response, it is necessary to diminish background environmental influences and highlight the particular event. However, surface-driven nonspecific interactions of the abundant biomolecules from the environment influence the targeted cell response significantly. Yes-associated protein (YAP) translocation may serve as a marker of human hepatocellular carcinoma (Huh7) cell responses to the extracellular matrix and surface-mediated stresses. Here, we propose a platform of tunable functionable antifouling poly(carboxybetain) (pCB)-based brushes to achieve a molecularly clean background for studying arginine, glycine, and aspartic acid (RGD)-induced YAP-connected mechanotransduction. Using two different sets of RGD-functionalized zwitterionic antifouling coatings with varying compositions of the antifouling layer, a clear correlation of YAP distribution with RGD functionalization concentrations was observed. On the other hand, commonly used surface passivation by the oligo(ethylene glycol)-based self-assembled monolayer (SAM) shows no potential to induce dependency of the YAP distribution on RGD concentrations. The results indicate that the antifouling background is a crucial component of surface-based cellular response studies, and pCB-based zwitterionic antifouling brush architectures may serve as a potential next-generation easily functionable surface platform for the monitoring and quantification of cellular processes.
Phospholipid Arachidonic Acid Remodeling During Phagocytosis in Mouse Peritoneal Macrophages
Authors: Gil-de-Gómez Luis , Monge Patricia , Rodríguez Juan P. , Astudillo Alma M. , Balboa María A. , Balsinde Jesús
Published: August 2020

Macrophages contain large amounts of arachidonic acid (AA), which distributes differentially across membrane phospholipids. This is largely due to the action of coenzyme A-independent transacylase (CoA-IT), which transfers the AA primarily from diacyl choline-containing phospholipids to ethanolamine-containing phospholipids. In this work we have comparatively analyzed glycerophospholipid changes leading to AA mobilization in mouse peritoneal macrophages responding to either zymosan or serum-opsonized zymosan (OpZ). These two phagocytic stimuli promote the cytosolic phospholipase A2-dependent mobilization of AA by activating distinct surface receptors. Application of mass spectrometry-based lipid profiling to identify changes in AA-containing phospholipids during macrophage exposure to both stimuli revealed significant decreases in the levels of all major choline phospholipid molecular species and a major phosphatidylinositol species. Importantly, while no changes in ethanolamine phospholipid species were detected on stimulation with zymosan, significant decreases in these species were observed when OpZ was used. Analyses of CoA-IT-mediated AA remodeling revealed that the process occurred faster in the zymosan-stimulated cells compared with OpZ-stimulated cells. Pharmacological inhibition of CoA-IT strongly blunted AA release in response to zymosan but had only a moderate effect on the OpZ-mediated response. These results suggest a hitherto undescribed receptor-dependent role for CoA-independent AA remodeling reactions in modulating the eicosanoid biosynthetic response of macrophages. Our data help define novel targets within the AA remodeling pathway with potential use to control lipid mediator formation
Neutrophil Extracellular Traps Impair Intestinal Barrier Function during Experimental Colitis
Authors: Lin Elliot Yi-Hsin , Lai Hsuan-Ju , Cheng Yuan-Kai , Leong Kai-Quan , Cheng Li-Chieh , Chou Yi-Chun , Peng Yu-Chun , Hsu Yi-Hsuan , Chiang Hao-Sen
Published: August 2020

Aberrant neutrophil extracellular trap (NET) formation and the loss of barrier integrity in inflamed intestinal tissues have long been associated with inflammatory bowel disease (IBD). However, whether NETs alter intestinal epithelium permeability during colitis remains elusive. Here, we demonstrated that NETs promote the breakdown in intestinal barrier function for the pathogenesis of intestinal inflammation in mouse models of colitis. NETs were abundant in the colon of mice with colitis experimentally induced by dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzene sulfonic acid (TNBS). Analysis of the intestinal barrier integrity revealed that NETs impaired gut permeability, enabling the initiation of luminal bacterial translocation and inflammation. Furthermore, NETs induced the apoptosis of epithelial cells and disrupted the integrity of tight junctions and adherens junctions. Intravenous administration of DNase I, an enzyme that dissolves the web-like DNA filaments of NETs, during colitis restored the mucosal barrier integrity which reduced the dissemination of luminal bacteria and attenuated intestinal inflammation in both DSS and TNBS models. We conclude that NETs serve a detrimental factor in the gut epithelial barrier function leading to the pathogenesis of mucosal inflammation during acute colitis.
Fast Detection of 2,4,6-Trinitrotoluene (TNT) at ppt Level by a Laser-Induced Immunofluorometric Biosensor
Authors: Paul Martin , Tscheuschner Georg , Herrmann Stefan , Weller Michael G.
Published: August 2020

The illegal use of explosives by terrorists and other criminals is an increasing issue in public spaces, such as airports, railway stations, highways, sports venues, theaters, and other large buildings. Security in these environments can be achieved by different means, including the installation of scanners and other analytical devices to detect ultra-small traces of explosives in a very short time-frame to be able to take action as early as possible to prevent the detonation of such devices. Unfortunately, an ideal explosive detection system still does not exist, which means that a compromise is needed in practice. Most detection devices lack the extreme analytical sensitivity, which is nevertheless necessary due to the low vapor pressure of nearly all explosives. In addition, the rate of false positives needs to be virtually zero, which is also very difficult to achieve. Here we present an immunosensor system based on kinetic competition, which is known to be very fast and may even overcome affinity limitation, which impairs the performance of many traditional competitive assays. This immunosensor consists of a monolithic glass column with a vast excess of immobilized hapten, which traps the fluorescently labeled antibody as long as no explosive is present. In the case of the explosive 2,4,6-trinitrotoluene (TNT), some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and chip-based mixing-devices and flow-cells. The system achieved limits of detection of 1 pM (1 ppt) of the fluorescent label and around 100 pM (20 ppt) of TNT. The total assay time is less than 8 min. A cross-reactivity test with 5000 pM solutions showed no signal by pentaerythritol tetranitrate (PETN), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). This immunosensor belongs to the most sensitive and fastest detectors for TNT with no significant cross-reactivity by non-related compounds. The consumption of the labeled antibody is surprisingly low: 1 mg of the reagent would be sufficient for more than one year of continuous biosensor operation.
Customer Value Types Predicting Consumer Behavior at Dutch Grocery Retailers
Authors: Janssens Kim , Lambrechts Wim , Keur Henriëtte , Semeijn Janjaap
Published: August 2020

The purpose of this paper is to profile three grocery retail formats (non-discounter, soft discounter, and hard discounter) in the Netherlands using Holbrook’s value types. These value types are linked to three consumer behavior outcomes, i.e., Satisfaction, Repurchase intention, and Word-of-Mouth. The impact of the retail formats is evaluated on the importance and performance of the value types, using a questionnaire for each of the retail formats. The relationship between the value types and outcomes is tested with partial least squares structural equation modeling (PLS-SEM). Aesthetics, Altruistic value, and Efficiency are positively linked to Satisfaction. In addition, Efficiency is the key driver for Repurchase intention and has a positive impact on Word-of-Mouth. A positive Word-of-Mouth is predicted by Social value and Service excellence. The three examined retail formats show a difference in Holbrook’s value types. Overall, the results of the non- and soft discounters differ from the hard discounters. Remarkably, and contrary to previous studies, the soft discounter’s scores are the highest meaning that consumers are most critical for this retail format. It seems that consumers expect the best of both worlds at soft discounters: low prices, interesting bargains, easy access, but also appealing store design, and excellent service.
Conditional Probability of Survival and Prognostic Factors in Long-Term Survivors of High-Grade Serous Ovarian Cancer
Authors: Fabbro Michel , Colombo Pierre-Emmanuel , Leaha Cristina Marinella , Rouanet Philippe , Carrère Sébastien , Quenet François , Gutowski Marian , Mourregot Anne , D’Hondt Véronique , Coupier Isabelle , Vendrell Julie , Vilquin Paul , Pujol Pascal , Solassol Jérôme , Mollevi Caroline
Published: August 2020

Objective: High-grade serous ovarian cancers (HGSOC) are heterogeneous, often diagnosed at an advanced stage, and associated with poor overall survival (OS, 39% at five years). There are few data about the prognostic factors of late relapses in HGSOC patients who survived ≥five years, long-term survivors (LTS). The aim of our study is to assess the probability of survival according to the already survived time from diagnosis. Methods: Data from HGSOC patients treated between 1995 and 2016 were retrospectively collected to estimate the conditional probability of survival (CPS), probability of surviving Y years after diagnosis when the patient had already survived X years, and to determine the LTS prognostic factors. The primary endpoint was OS. Results: 404 patients were included; 120 of them were LTS. Patients were aged 61 years (range: 20–89), WHO performance status 0–1 in 86.9% and 2 in 13.1%, and Fédération Internationale de Gynécologie et d’Obstétrique (FIGO) staging III and IV in 82.7% and 17.3% patients. Breast cancer (BRCA) status was available in 116 patients (33% mutated), including 58 LTS (36% mutated). No macroscopic residual disease was observed in 58.4% patients. First-line platinum-based chemotherapy plus paclitaxel was administered in 80.4% of patients (median: six cycles (range: 1–14)). After a 9 point 3-year follow-up, median OS was four years (95% CI: 3.6–4.5). The CPS at five years after surviving one year was 42.8% (95% CI: 35.3–48.3); it increased to 81.7% (95% CI: 75.5–87.8) after four survived years. Progression-free interval>18 months was the only LTS prognostic factor in the multivariable analysis (hazard ratio (HR) = 0.23; 95% CI: 0.13–0.40; p < 0.001). Conclusion: The CPS provided relevant and encouraging clinical information on the life expectancy of HGSOC patients who already survived a period of time after diagnosis. LTS prognostic factors are useful for clinicians and patients.
Therapeutic Zfra4-10 or WWOX7-21 Peptide Induces Complex Formation of WWOX with Selective Protein Targets in Organs that Leads to Cancer Suppression and Spleen Cytotoxic Memory Z Cell Activation In Vivo
Authors: Su Wan-Pei , Wang Wan-Jen , Chang Jean-Yun , Ho Pei-Chuan , Liu Tsung-Yun , Wen Kuang-Yu , Kuo Hsiang-Ling , Chen Yu-Jie , Huang Shenq-Shyang , Subhan Dudekula , Chen Yu-An , Lu Chen-Yu , Wu Chia-Yun , Lin Sing-Ru , Lee Ming-Hui , Chiang Ming-Fu , Sze Chun-I , Chang Nan-Shan
Published: August 2020

Synthetic Zfra4-10 and WWOX7-21 peptides strongly suppress cancer growth in vivo. Hypothetically, Zfra4-10 binds to the membrane Hyal-2 of spleen Z cells and activates the Hyal-2/WWOX/SMAD4 signaling for cytotoxic Z cell activation to kill cancer cells. Stimulation of membrane WWOX in the signaling complex by a WWOX epitope peptide, WWOX7-21, is likely to activate the signaling. Here, mice receiving Zfra4-10 or WWOX7-21 peptide alone exhibited an increased binding of endogenous tumor suppressor WWOX with ERK, C1qBP, NF-κB, Iba1, p21, CD133, JNK1, COX2, Oct4, and GFAP in the spleen, brain, and/or lung which led to cancer suppression. However, when in combination, Zfra4-10 and WWOX7-21 reduced the binding of WWOX with target proteins and allowed tumor growth in vivo. In addition to Zfra4-10 and WWOX7-21 peptides, stimulating the membrane Hyal-2/WWOX complex with Hyal-2 antibody and sonicated hyaluronan (HAson) induced Z cell activation for killing cancer cells in vivo and in vitro. Mechanistically, Zfra4-10 binds to membrane Hyal-2, induces dephosphorylation of WWOX at pY33 and pY61, and drives Z cell activation for the anticancer response. Thus, Zfra4-10 and WWOX7-21 peptides, HAson, and the Hyal-2 antibody are of therapeutic potential for cancer suppression.