bluuebunny/crossref_metadata_2025_split huggingface dataset:
Terahertz Radiation Transport in Photonic Glasses
Authors: Gentilini Silvia , Missori Mauro , Ghofraniha Neda , Conti Claudio 
Published: July 2020

AbstractMultiple scattering of electromagnetic (EM) waves arises in disordered media with a refractive index varying on the scale of the wavelength. The diffusion approximation is a powerful tool to treat multiple scattering as a photon random walk, neglecting resonant phenomena. However, as the light intensity varies on a scale much smaller than the transport mean free path, resonances may occur in media formed by finite‐size scatterers and break the diffusion approximation. The energy and phase velocity are very useful tools to reveal the onset of the resonant transport regime. In this paper the study of the propagation of terahertz (THz) waves through 3D random media by employing terahertz time‐domain spectroscopy (THz‐TDS) is addressed. Specifically, measurements of the electric field transmitted by samples of different thicknesses made of 1 mm diameter silica spheres dispersed in a paraffin matrix at different filling fractions are reported. This investigation has provided an accurate measurement of the EM field phase and, hence, information on the radiation propagation velocity that has enabled the first observation of a photonic glass at the THz range.
Topologically Protected and Highly Localized Surface Waves in Gyro‐Electromagnetic Metamaterials
Authors: Han Ning , Liu Jianlong , Gao Yang , Zhou Keya , Liu Shutian 
Published: July 2020

AbstractTopological insulators are internally insulating but allow topologically protected surface waves at the boundary. In this work, the photonic analogue of topologically protected surface states in gyro‐electromagnetic metamaterials are discovered. It is analytically and numerically demonstrated that the surface waves appear not only in the k‐space common gap regions between the bulk states of the metamaterials and the vacuum state, but even can exist in an infinitely extended k‐space. Such surface waves have extremely large wave vectors along the propagation direction with high field localization on the surface. It is believed that the high field localization of surface waves could improve the compactness of photonic devices and facilitate the integration of photonic circuits.
An application of factor analysis in wet particle systems: Rolling friction and cohesive liquid controlling performances
Authors: Tang Tianqi , Wang Tianyu , Ren Anxing , Zhao Yunhua , He Yurong 
Published: July 2020

AbstractFluidized beds are widely used in many chemical engineering industrials, and flow behaviors of multiphase flow have always been the focus of research. This paper presented how rolling friction and cohesive liquid affected wet particle flow behaviors by experiments, simulation, and data analyses. Experiments were conducted for applying a suitable range of rolling friction coefficient. A discrete element method, well validated by comparing experimental data, was developed and demonstrated that μr = 0.125 was a good choice for particles applied in this work. Data from numerical results were well analyzed by factor analysis, where explained interaction effect of two factors on fluidized beds. Factor analyses reflected that dominating factor and interaction effect on flow behaviors vary instead of single control factor in different regions. These findings have clearly showed importance and effect of microscopic parameter collision characteristics on the hydrodynamic behaviors in fluidized beds. Thus, rolling friction constitutes should be carefully considered to ensure that theoretical results are accurate.
Pervaporation separation of levulinic acid aqueous solution by ZSM‐5/PDMS composite membrane
Authors: Zhang Zongqi , Wu Yuanfeng , Gao Lijing , Xiao Guomin 
Published: July 2020

AbstractThis work aims at investigating the special application of ZSM‐5/polydimethylsiloxane (PDMS) membrane being used for pervaporation separation of levulinic acid aqueous solutions. The effects of temperature, downstream pressure, feed concentration, and raw material ratio on the separation performance are investigated by self‐made flat‐sheet films. When the flow rate of feed pump remained at 0.4 ml/min (10 wt% levulinic acid), a levulinic acid permeation flux of 334.13 g/(m2h) and a separation factor of 2.382 at 75°C are observed over the composite membrane doped with 10 wt% ZSM‐5. In addition, the acid resistance is enhanced after the PDMS membranes are doped with ZSM‐5. Besides, the functionalized process also makes the membranes increase in its hydrophobicity. The results demonstrate that the ZSM‐5/PDMS‐based membranes show profound prospects for separating levulinic acid aqueous solution.
1,2,3‐Triazole‐linked 5‐benzylidene (thio)barbiturates as novel tyrosinase inhibitors and free‐radical scavengers
Authors: Ranjbar Sara , Shahvaran Parisa‐sadat , Edraki Najmeh , Khoshneviszadeh Mahsima , Darroudi Mahdieh , Sarrafi Yaghoub , Hamzehloueian Mahshid , Khoshneviszadeh Mehdi 
Published: July 2020

AbstractIn this study, benzyl‐1,2,3‐triazole‐linked 5‐benzylidene (thio)barbiturate derivatives 7a–d and 8a–h were designed as potential tyrosinase inhibitors and free‐radical scavengers. The twelve derivatives were synthesized via the [3+2] cycloaddition reaction of the corresponding benzyl azide as a dipole and the corresponding alkyne as a dipolarophile in the presence of copper(I) species, generated in situ from copper(II)/ascorbate. The thiobarbiturate derivative 8h and the barbiturate derivative 8b bearing 4‐fluoro and 4‐bromo groups on the benzyl–triazole moiety were found to be the most potent tyrosinase inhibitors with IC50 values of 24.6 ± 0.9 and 26.8 ± 0.8 μM, respectively. Almost all the compounds showed a good radical scavenging activity with EC50 values in the range of 29.9–324.9 μM. Derivatives 7a, 8f, and 8h were the most potent free‐radical scavengers with EC50 values of 29.9 ± 0.8, 36.8 ± 0.9, and 39.2 ± 1.1 μM, respectively. The kinetic analysis revealed that compound 8h was a mixed‐type tyrosinase inhibitor. The molecular docking analysis indicated that 8b and 8h were well accommodated in the active site of the tyrosinase enzyme and possessed the most negative binding energy values of −8.55 and −8.81 kcal/mol, respectively. Moreover, it was found that the two residues, Asn81 and Glu322, played a significant role in forming stable enzyme–inhibitor complexes.
Versuche zum Querkrafttragverhalten bei gleichzeitiger Zugnormalkraft
Authors: Adam Viviane , Claßen Martin , Hegger Josef 
Published: July 2020

AbstractQuerkraftbeanspruchte Stahlbetonplatten können unter bestimmten Umständen durch zusätzliche Zugnormalspannungen belastet sein. Beispiele dafür sind Platten unter Zwangbeanspruchung, Stahlbetonfahrbahnplatten von Verbundbogenbrücken oder Silowände. Der Ansatz zur Berücksichtigung von Normalspannungen im aktuellen Bemessungskonzept für Querkraft ohne Querkraftbewehrung nach Eurocode 2 (EC2) wurde über Versuche an vorgespannten Einfeldträgern kalibriert. Da der Einfluss von Zugnormalkräften durch den Bemessungsansatz nur näherungsweise erfasst wird, wurden am Institut für Massivbau der RWTH Aachen Versuche an Plattenstreifen unter Querkraft‐ und gleichzeitiger Zugnormalkraftbeanspruchung durchgeführt. Neben Einfeldträgern wurden auch Plattenstreifen mit Durchlaufwirkung getestet, um den Einfluss praxisnaher statischer Systeme zu untersuchen. Durch den Momentenwechsel im Mehrfeldsystem entsteht ein Bereich ohne Biegebeanspruchung, der das Schubfeld in zwei Abschnitte unterteilt (Feld‐ und Stützmomentenbereich). Da sich beim Biegeschubversagen der maßgebende Schubriss in der Regel aus einem Biegeriss entwickelt, wird das Tragverhalten zum einen durch das statische System beeinflusst und zum anderen durch die kombinierte Normalkraft‐ und Biegebeanspruchung. Abweichend vom linearen Ansatz der Normalspannung im EC2 wurde in den eigenen experimentellen Untersuchungen sowie bei Versuchen aus der Literatur mit steigender Zugbeanspruchung ein degressiver Einfluss der Zugnormalspannung auf die Querkrafttragfähigkeit festgestellt.
Overexpression of ER Protein Processing and Apoptosis Regulator Genes in Human Embryonic Kidney 293 Cells Improves Gene Therapy Vectors Production
Authors: Formas‐Oliveira Ana S. , Basílio João S. , Rodrigues Ana F. , Coroadinha Ana S. 
Published: July 2020

AbstractGammaretroviral and lentiviral vectors (γ‐RV and LV) are among the most used vectors in gene therapy. Currently, human embryonic kidney (HEK) 293 cells, the manufacture platform of choice for these vectors, provide low transducing particle yields, challenging their therapeutic applications and commercialization. This work studies metabolic pathways, focusing on endoplasmic reticulum (ER) protein processing and anti‐apoptotic mechanisms, influencing vector productivity in HEK 293 cell substrates. To that end, four candidate genes—protein disulfide isomerase family A member 2 gene, heat shock protein family A (Hsp70) member 5 gene, X‐box binding protein 1 gene (ER protein processing), and B‐cell lymphoma 2 protein gene (anti‐apoptotic)—are individually stably expressed in the cells. How their overexpression level influence vector yields is analyzed by establishing cell populations with incremental genomic copies of each. γ‐RV volumetric productivity increases up to 97% when overexpressing ER protein processing genes. LV volumetric production increases 53% when overexpressing the anti‐apoptotic gene. Improvements are associated with higher cell specific productivities and dependent on gene overexpression level, highlighting the importance of fine‐tuning gene expression. Overall, this work discloses gene engineering targets enabling efficient gene therapy product manufacture showing that ER protein processing and anti‐apoptotic pathways are pivotal to producer cell performance.
The contagion effect of environmental violations: The case of Dieselgate in Germany
Authors: Bouzzine Yassin Denis , Lueg Rainer 
Published: July 2020

AbstractWe examine how environmental violations affect the stock returns of the violating firm and how these financial implications then spread to industry peers. Volkswagen's diesel emissions scandal (Dieselgate) and the German automotive industry serve as a seminal case for the examination. Research often limits examinations of corporate environmental scandals to the primary event announcement. Yet the Dieselgate scandal exhibits a processual character that requires the examination of multiple events over time. We identify 10 Dieselgate events and employ event study methodology to detect abnormal stock reactions. Based on agency and signaling theory, the results indicate that Dieselgate has harmed the stock returns of Volkswagen and its industry peers substantially. Surprisingly, Volkswagen suffered financial damage only upon the initial event of Dieselgate. Subsequent events had significant effects only on industry peers. These findings contribute comprehensively to the research of environmental misconduct and provide valuable implications for practitioners.
Role of the oral microbiota in cancer evolution and progression
Authors: Sun Jiwei , Tang Qingming , Yu Shaoling , Xie Mengru , Xie Yanling , Chen Guangjin , Chen Lili 
Published: July 2020

AbstractBacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial roles in the health status of individuals. Epidemiological studies related to molecular pathology have revealed that there is a close relationship between oral microbiota and tumor occurrence. Oral microbiota has attracted considerable attention for its role in in‐situ or distant tumor progression. Anaerobic oral bacteria with potential pathogenic abilities, especially Fusobacterium nucleatum and Porphyromonas gingivalis, are well studied and have close relationships with various types of carcinomas. Some aerobic bacteria such as Parvimonas are also linked to tumorigenesis. Moreover, human papillomavirus, oral fungi, and parasites are closely associated with oropharyngeal carcinoma. Microbial dysbiosis, colonization, and translocation of oral microbiota are necessary for implementation of carcinogenic functions. Various underlying mechanisms of oral microbiota‐induced carcinogenesis have been reported including excessive inflammatory reaction, immunosuppression of host, promotion of malignant transformation, antiapoptotic activity, and secretion of carcinogens. In this review, we have systemically described the impact of oral microbial abnormalities on carcinogenesis and the future directions in this field for bringing in new ideas for effective prevention of tumors.
Mesenchymal stem cells derived‐exosomes as a new therapeutic strategy for acute soft tissue injury
Authors: Yang Hongchang , Zhou Jing , Pan Hongyao , Wei Wei , Gao Run , Zhou Qiang 
Published: July 2020

AbstractThe study aimed to investigate the role of exosomes derived from rat bone marrow mesenchymal stem cells (rBMSCs) in acute soft tissue injury and its related mechanisms. Exosomes were isolated from rBMSCs and characterized by Nanosight NS300 particle size analyser (NTA), transmission electron microscopy (TEM), and western blot. Twenty four rats were randomly divided into four groups (n = 6): control group, strike group, rBMSCs group, and rBMSCs‐exo group. Haematoxylin‐eosin (HE) staining was used to observe the morphology. Real‐time quantification PCR (RT‐qPCR) and western blot were used to analyse the expression ofIL‐1A,IL‐12A,COL11A1,COL4A4, andWnt4. NTA, TEM and western blot results showed that exosomes isolated from rBMSCs were cup‐shaped morphology with a size of about 100 nm. HE staining showed that there was severe soft tissue inflammation in strike group, and the symptoms were alleviated after rBMSCs and rBMSCs‐exo treatment. RT‐qPCR and western blot indicated that in the strike group, the expression levels ofIL‐1AandIL‐12Awere significantly increased, and their expressions were decreased markedly by exosomes treatment. In addition, after treatment, the expression levels ofCOL11A1andWnt4were up‐regulated, while the expression ofCOL4A4was down‐regulated. Exosomes isolated from rBMSCs could improve acute soft tissue injury, and may be used as a new therapeutic strategy acute soft tissue injury.Significance of the studyAcute soft tissue injury is a common clinical exercise injury, which has a significant impact on people's health and work ability. Exosomes have been attracting increasing attention as a media of cell‐to‐cell communication. This study showed that exosomes isolated from rBMSCs could improve acute soft tissue injury by inhibiting inflammatory response, regulating the levels ofCOL11A1andCOL4A4, and up‐regulating the expression ofWnt4. These will provide a new therapy strategy of acute soft tissue injury, and improve our understanding of the occurrence and development in acute soft tissue injury.
N‐Aryl Amides as Chemical Exchange Saturation Transfer Magnetic Resonance Imaging Contrast Agents
Authors: Cai Xuekang , Zhang Jia , Lu Jiaqi , Yi Long , Han Zheng , Zhang Shuixing , Yang Xing , Liu Guanshu 
Published: July 2020

AbstractChemical exchange saturation transfer (CEST) MRI has recently emerged as a versatile molecular imaging approach in which diamagnetic compounds can be utilized to generate an MRI signal. To expand the scope of CEST MRI applications, herein, we systematically investigated the CEST properties of N‐aryl amides with different N‐aromatic substitution, revealing their chemical shifts (4.6–5.8 ppm) and exchange rates (up to thousands s−1) are favorable to be used as CEST agents as compared to alkyl amides. As the first proof‐of‐concept study, we used CEST MRI to detect the enzymatic metabolism of the drug acebutolol directly by its intrinsic CEST signal without any chemical labeling. Our study implies that N‐aryl amides may enable the label‐free CEST MRI detection of the metabolism of many N‐aryl amide‐containing drugs and a variety of enzymes that act on N‐aryl amides, greatly expanding the scope of CEST MR molecular imaging.
What is Best Strategy for Water Soluble Fluorescence Dyes?—A Case Study Using Long Fluorescence Lifetime DAOTA Dyes**
Authors: Bisballe Niels , Laursen Bo W. 
Published: July 2020

AbstractThe lipophilic nature of organic dyes complicates their effectiveness in aqueous solutions. In this work we investigate three different strategies for achieving water‐solubility of the diazaoxatriangulenium (DAOTA+) chromophore: hydrophilic counter ions, aromatic sulfonation of the chromophore, and attachment of charged side chains. The long fluorescence lifetime (FLT, τf=20 ns) of DAOTA+ makes it a sensitive probe to analyze solvation and aggregation effects. Direct sulfonation of the chromophore was found to increase solubility drastically, but at the cost of greatly reduced quantum yields (QYs) due to enhanced non‐radiative deactivation processes. The introduction of either cationic (4) or zwitterionic side chains (5), however, brings the FLT (τf=18 ns) and QY (ϕf=0.56) of the dye to the same level as the parent chromophore in acetonitrile. Time‐resolved fluorescence spectroscopy also reveals a high resistance to aggregation and non‐specific binding in a high loading of bovine serum albumin (BSA). The results clearly show that addition of charged flexible side chains is preferable to direct sulfonation of the chromophore core.
Immediate histologic correlation in women with atypical squamous cells of undetermined significance cytology and positive high‐risk HPV: A retrospective review of 6000 cases in a large academic women's hospital
Authors: Zhang Huina , Pradhan Dinesh , Wang Tiannan , Ashman Dayne , Matsko Jonee , Zhao Chengquan 
Published: July 2020

BackgroundPrevious studies of the histologic correlation in women who have atypical squamous cells of undetermined significance cytology (ASC‐US) and are positive for high‐risk human papillomavirus (hrHPV+) have predominantly utilized the Hybrid Capture 2 (HC2) test, whereas the use of other US Food and Drug Administration (FDA)‐approved methods is relatively limited.MethodsCases of ASC‐US/hrHPV+ that were tested using HC2, Cervista, or Aptima were retrieved, and the immediate histologic correlations were analyzed.ResultsOverall, 53.9% (n = 3238) of women with ASC‐US/hrHPV+ had immediate histologic correlation. The detection rates for grade 1 cervical intraepithelial neoplasia (CIN1) were similar among the 3 methods (37.1%‐41.8%), while the overall detection rates for grade 2 CIN or higher (CIN2+) were much lower (5.1%‐9.0%). CIN2+ detection rates were similar among different age groups for HC2 testing, whereas for Cervista and Aptima testing, detection rates were highest in the youngest group (age <25 years) and decreased with age. Statistical analyses revealed that the CIN2+ detection rate was significantly higher in younger women who were tested with Cervista.ConclusionThese hrHPV testing methods revealed low CIN2+ detection rates in women with ASC‐US/hrHPV+ but demonstrated different patterns when using age‐stratified analyses. The high rate of CIN2+ detection in women aged <25 years by the Cervista and Aptima testing platforms, but not the HC2 platform, suggest that continual investigation of FDA‐approved clinical hrHPV testing—especially large‐scale, long‐term, prospective studies—is needed to evaluate the best options for management of ASC‐US/hrHPV+ in this age group.
Hybrid Nanotube Assembly and Hierarchical ZSM‐23 Zeolite Synthesized with Cationic Polymer and Enhanced Performance in n‐Heptane Hydroisomerization
Authors: Tontisirin Supak , Ernst Stefan , Wilhelm Christian 
Published: July 2020

AbstractNovel nanotube assembly and hierarchical ZSM‐23 zeolite can be fabricated by using the low‐cost and commercial cationic polymer of polydiallyldimethylammonium chloride (polyDDA) in the synthesis gel. In this facile synthesis, the polyDDA plays roles as the growth inhibitor for nanosized crystals and the secondary porogen. This unique crystal structure shows tubular nanocrystals assembling to form agglomerates. This hierarchical structure combines intercrystalline mesopore and narrow macropore to the micropore of ZSM‐23. Double advantages of nanocrystal and hierarchical structure contribute to higher pore mouths and enhanced diffusion of the reaction molecules. The hierarchical form also benefits for simple crystal recovery of nanozeolite by filtration. The n‐heptane hydroisomerization shows the derived Pt/H‐ZSM‐23 outperforms the conventional Pt/H‐ZSM‐23 with higher isomer yield at higher conversion and less cracked product yield. This could be attributed to higher pore mouths and efficient mass transport because of the shorter diffusion path length by the smaller crystal and hierarchical structure supplementing pore‐to‐pore connection of the molecular transport.
Unequal‐interval based loosely coupled control method for auto‐scaling heterogeneous cloud resources for web applications
Authors: Cai Zhicheng , Liu Duan , Lu Yifei , Buyya Rajkumar 
Published: July 2020

SummaryMost existing quality of service (QoS) control algorithms of Web applications take into account Web Server or database connections which can be released immediately. However, many applications are deployed on virtual machines (VMs) or even Spot VMs elastically rented from public Clouds. To save costs, interval‐priced VMs are not released until the ends of rented intervals. Such delays of control effects make existing methods rent or release excess VMs leading to overcontrol. Fluctuated prices make Spot VMs unreliable due to unexpected termination which makes fault‐tolerant strategies crucial. In this article, an unequal‐interval‐based loosely coupled control method is proposed to improve the quality of service (QoS) control ability of fault‐tolerant strategies. A queuing model with arrival‐rate‐adjustment coefficient is used to predict required capacity as a feedforward controller. Another two‐threshold and queuing‐model‐based method is applied to update the coefficient as a loosely coupled feedback controller. Meanwhile, unequal‐interval controller collaborating method is proposed to avoid overcontrol and react quickly to workload changes. Our approach is evaluated on both a simulation platform and a real Kubernetes Cluster. Experimental results illustrate that our approach decreases the percentage of waiting times larger than service level agreements with similar or lower rental costs compared with existing algorithms.
Generation of Complete Multi−Cell Type Lung Organoids From Human Embryonic and Patient‐Specific Induced Pluripotent Stem Cells for Infectious Disease Modeling and Therapeutics Validation
Authors: Leibel Sandra L. , McVicar Rachael N. , Winquist Alicia M. , Niles Walter D. , Snyder Evan Y. 
Published: July 2020

AbstractThe normal development of the pulmonary system is critical to transitioning from placental‐dependent fetal life to alveolar‐dependent newborn life. Human lung development and disease have been difficult to study due to the lack of an in vitro model system containing cells from the large airways and distal alveolus. This article describes a system that allows human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) to differentiate and form three‐dimensional (3D) structures that emulate the development, cytoarchitecture, and function of the lung (“organoids”), containing epithelial and mesenchymal cell populations, and including the production of surfactant and presence of ciliated cells. The organoids can also be invested with mesoderm derivatives, differentiated from the same human pluripotent stem cells, such as alveolar macrophages and vasculature. Such lung organoids may be used to study the impact of environmental modifiers and perturbagens (toxins, microbial or viral pathogens, alterations in microbiome) or the efficacy and safety of drugs, biologics, and gene transfer. © 2020 Wiley Periodicals LLC.Basic Protocol: hESC/hiPSC dissection, definitive endoderm formation, and lung progenitor cell induction