bluuebunny/crossref_metadata_2025 huggingface dataset:
Extrinsic Absorption Pathways in Vanadium‐Doped SiC Measured Using a Total Internal Reflection Geometry
Authors: Kramer Noah J. , Voss Lars F. , Conway Adam M. , Grivickas Paulius V. , Bora Mihail , Hall David L. , Caruso Anthony N.
Published: August 2020

Vanadium‐doped SiC is under study for high‐power photoconductive switches and is receiving increased attention as a potential material system for quantum computing, as the V can act as a quantum emitter at telecom wavelengths. Knowledge of the defect‐mediated electronic transition pathways from sub‐bandgap illumination in this material with low absorption and multi‐photon and multi‐path transition probability is important in optimizing quantum efficiency. Herein, the optical transitions of vanadium‐doped SiC for two polytypes as a function of dopant concentration using a total internal reflection (TIR) geometry are examined. Normalized quantum efficiency is reported and correlated with both dopant concentrations (V, N, B, and Al) measured by secondary ion mass spectroscopy (SIMS) and absorption measurements. Although both polytypes respond well to 532 nm light, efficiency at longer wavelengths does not correlate 1:1 with absorption coefficient and strongly depends on the polytype and net background co‐dopant concentration. This has important implications for efficient excitation of both carriers for optoelectronics and for the use of V as a quantum emitter.
Effect of Nitrogen Doping on Threshold Voltage in Amorphous Ga2Te3 for Application of Selector Devices
Authors: Lee Dayoon , Kim Taeho , Kim Jaeyeon , Sohn Hyunchul
Published: August 2020

The implementation of ultrahigh‐density cross‐point array structures has received considerable interest as emerging storage devices, and threshold switching devices are regarded to be promising as to the suppression of leakage current in cross‐point array structures. Threshold switching devices need to modulate the threshold voltage (Vth) depending on the various memory elements to achieve proper selector device in cross‐point array structures. However, only limited methods are available for controlling Vth. Therefore, the nitrogen (N) doping effects on trap states, density of localized states, and Vth of the amorphous Ga2Te3 (a‐Ga2Te3) selector devices are investigated herein. Furthermore, the electrical conduction behavior is fitted using a trap‐controlled space charge limited conduction mechanism with two transition voltages, i.e., the space charge limited voltage (VSCL) and trap‐filled limited voltage (VTFL). The optical bandgap energy and optical Urbach energy are affected by the N doping in a‐Ga2Te3. In addition, N doping in a‐Ga2Te3 increases the density of localized states. These effects increase both the transition voltages (VSCL and VTFL). Thus, doping a‐Ga2Te3 with N reduces Vth when the trap states are changed. Furthermore, N‐doped a‐Ga2Te3 selector devices exhibit highly reliable switching up to 109 cycles.
Enhanced reliability analysis method for multistate systems with epistemic uncertainty based on evidential network
Authors: Zhang Zhe , Chen Ziwei , Jiang Chao
Published: August 2020

Evidential network is considered to have superiority in conducting reliability analysis for complex engineering systems with epistemic uncertainty. However, existing methods tend to result in combinational explosion when multistate systems are involved in the reliability analysis, which means the reliability analysis cost increases exponentially with the number of components and that of functioning states. Therefore, an enhanced reliability analysis method is proposed in this paper for reliability analysis and performance evaluation of multistate systems with epistemic uncertainty, through which the combination explosion can be significantly alleviated. Firstly, the functioning states of each component are sequenced according to utility functions. Secondly, the basic belief assignment (BBA) of each component is reassigned in terms of commonality function, through which the BBA defined in the power set space is represented by two extreme BBA distributions defined in the frame of discernment. Thirdly, the reliability intervals of the system states are calculated through evidential network, and the system performance level is computed. Two multistate system numerical examples are investigated to demonstrate the effectiveness and efficiency of the proposed method.
A new exponentially weighted moving average chart with an adaptive control scheme for high yield processes—An application in injection molding process
Authors: Abubakar Sani Salihu , Khoo Michael B.C. , Saha Sajal , Lee Ming Ha
Published: August 2020

Analytical formulae for computing the average time to signal (ATS) value for the exponentially weighted moving average (EWMA) cumulative count of conforming (CCC) chart using the Markov chain procedure are derived, as the performance of this chart is currently studied using simulation in the literature. Additionally, the variable sampling interval (VSI) EWMA CCC chart for monitoring the cumulative counts of items inspected until a nonconforming item is obtained in a high yield process and is developed to increase the sensitivity of the basic EWMA CCC chart. By using the Markov chain procedure, optimal parameters of the VSI EWMA CCC chart in minimizing the ATS value are obtained and provided to facilitate the chart's implementation in practice. It is found that the VSI EWMA CCC chart shows an impressive improvement over the basic CCC, VSI CCC, and EWMA CCC charts. An example using real data from an injection molding process producing micro‐prism array of an optical element is given to demonstrate the implementation of the VSI EWMA CCC chart in practice. The originality of this manuscript lies in the derivation of new Markov chain‐based analytical formulae for computing the ATS of the EWMA CCC chart and the incorporation of the VSI technique into the EWMA CCC chart to boost the out‐of‐control detection speed of the latter.
Process‐capability‐qualified adjustable multiple‐dependent‐state sampling plan for a long‐term supplier–buyer relationship
Authors: Wang To‐Cheng , Wu Chien‐Wei , Hsu Bi‐Min , Shu Ming‐Hung
Published: August 2020

Acceptance sampling plan is widely used for the inspections of incoming or outgoing products to provide the producer and the consumer a general benchmark for lot sentencing. To reduce the inspection cost, the multiple‐dependent‐state (MDS) plan that takes account of the preceding lots' quality history into the current lot disposition has been proposed. However, recent studies overlook the fact that the MDS plan's performance needed to reach target compliance decreases with an increase in the number of preceding lots considered. This unawareness makes the MDS plan fall into a conflictive situation. To overcome the drawback of the MDS plan, in this paper, we introduce a modified MDS plan to accommodate an adjustable mechanism, called adjustable MDS (AMDS) sampling plans. The presented AMDS plans are designed on the basis of the advanced process capability index, which is cognizant of both the process yield and the process loss. This established process‐capability‐qualified AMDS plan efficiently solves the conflictive situation of the MDS plan when encompassing more preceding lots in the lot‐disposition decision. Notably, its efficacy has been shown on high improvements in terms of the required sample size for the inspection, the discriminatory power, and the average run length for lot sentencing.
Quantum chemical study on the sensing properties of Pt‐decorated BC3 nanotube toward metronidazole drug
Authors: Ma Tianxiao , Jin Chao , Aslanzadeh Saeed Amir
Published: August 2020

Despite the important role of metronidazole (MNO) in treating giardiasis and amoebiasis, its intake may cause mutagenic‐, genotoxic‐, and carcinogenic‐type side reactions, so proper sensors are essential for MNO detection. In this work, we studied, using the density functional theory (DFT) approach, MNO adsorption on a pristine and Pt‐decorated BC3 nanotube (Pt@BCN) in order to assess their potential as drug‐sensing material. We showed that the pristine tube weakly adsorbed the MNO drug and cannot detect it. Next, we examined the most stable complexes for Pt decoration on the BNC, finding a more favorable binding energy (BE) for a Pt‐η6 with B2C4 hexagon. Several complexes were considered for MNO adsorption on the Pt@BCN. In the most stable complex, the MNO interacts with the Pt atom through the NO2 group with a BE of −1.51 eV. The sensing response of BCN dramatically increased from 5.7 up to 415.2 by the Pt decoration. A short recovery time of 1.54 seconds was reached for the MNO desorption from the Pt@BCN surface. The water solvent reduces the BE of both MNO and sensing response of the Pt@BCN to −1.36 eV and 303.9, respectively. Our study proposes that a Pt@BCN could act as a promising sensor for MNO drug detection purposes.
Cooperative effects between triel and halogen bonds in complexes of pyridine derivatives: An opposite effect of the nitrogen oxidation on triel and halogen bonds
Authors: Wang Ruijng , Xiao Bo , Li Wenzuo , Li Qingzhong
Published: August 2020

Ab initio calculations are performed for binary complexes of TrR3···4‐PyX/4‐OPyX and 4‐PyX/4‐OPyX···N‐base (Tr = B, Al; R = H, Cl, Br, I; X = Cl, Br, I; N‐base = HCN, NHCH2, NH3). The halogen bond (XB) is weak but becomes stronger in the HCN(sp) < NH3(sp3) < NHCH2(sp2) pattern. Nitrogen oxidation can enhance the XB a little. The triel bond (TrB) is very strong, with interaction energy ranging from −35 to −58 kcal/mol. The TrB is weaker for the heavier halogen atom in the AlR3complex, while no such dependence is found in the BR3complex. The oxygen atom of 4‐OPyX engages in a weaker TrB than the nitrogen atom of 4‐PyX, inconsistent with the negative molecular electrostatic potentials (MEPs) on both atoms. Both TrB and XB are strengthened in TrR3···4‐PyX/4‐PyOX···N‐base. The binding distance of the stronger TrB is shortened to less than that of the weaker XB, which is in contrast to that in BF3···NCH···NCH, where the stronger TrB has a larger shortening in the binding distance. The cooperativity is explained by MEP and charge transfer.
Can doping of transition metal oxide cathode materials increase achievable voltages with multivalent metals?
Authors: Koch Daniel , Manzhos Sergei
Published: August 2020

The use of substitutional p‐doping as a means to enhance the insertion energies of multivalent metals in transition metal oxides, and therefore the resulting voltages in an electrochemical cell, due to band structure modulation is investigated using first principles calculations. The investigations reveal the formation of n‐hole polarons (with n > 1) in the form of oxygen dimers in p‐doped charge‐transfer insulating transition metal oxides, caused by localized p holes on oxide ions in agreement with previous findings. It is found that the oxygen dimer formation has an adverse effect on adsorption energetics compared to the single‐hole case without dimerization. On the other hand, strained systems or Mott insulators with qualitatively different valence band composition do not exhibit oxygen dimerization with multihole doping. The results demonstrate the advantages and limitations of transition metal oxide electrode p‐doping and show a path to possible strategies to overcome detrimental effects.
Pseudoaneurysm after total arch replacement mimicking malignant lymphadenopathy
Authors: Chiba Yosuke , Yamasaki Kei , Ikegami Hiroaki , Yatera Kazuhiro
Published: August 2020

Key message

Pseudoaneurysm should be considered in the differential diagnosis when the computed tomography (CT) findings show a mediastinal mass in patients with a history of cardiovascular surgery even if such surgery occurred over two decades previously.
Comparing the accuracy of the da Vinci Xi and da Vinci Si for image guidance and automation
Authors: Ferguson James M. , Pitt Bryn , Kuntz Alan , Granna Josephine , Kavoussi Nicholas L. , Nimmagadda Naren , Barth Eric J. , Herrell Stanley Duke , Webster Robert J.
Published: August 2020

Background

Current laparoscopic surgical robots are teleoperated, which requires high fidelity differential motions but does not require absolute accuracy. Emerging applications, including image guidance and automation, require absolute accuracy. The absolute accuracy of the da Vinci Xi robot has not yet been characterized or compared to the Si system, which is now being phased out. This study compares the accuracy of the two.

Methods

We measure robot tip positions and encoder values assessing accuracy with and without robot calibration.

Results

The Si is accurate if the setup joints are not moved but loses accuracy otherwise. The Xi is always accurate.

Conclusion

The Xi can achieve submillimetric average error. Calibration improves accuracy, but excellent baseline accuracy of the Xi means that calibration may not be needed for some applications. Importantly, the external tracking systems needed to account for setup joint error in the Si are no longer required with the Xi.
The association between dengue viremia kinetics and dengue severity: A systemic review and meta‐analysis
Authors: Morsy Sara , Hashan Mohammad Rashidul , Hieu Truong Hong , Mohammed Abdelrahman Tarek , Elawady Sameh Samir , Ghosh Prithwish , Elgendy Manal A. , Le Huu‐Hoai , Hamad Walid Mohamed Attiah , Iqtadar Somia , Dumre Shyam Prakash , Hirayama Kenji , Huy Nguyen Tien
Published: August 2020

In this study, we aim to assess the association of dengue viremia with dengue severity. The study protocol was developed and registered in PROSPERO (CRD42016039864). We searched nine databases to find potential papers. Studies meeting the inclusion criteria were included. We, based our analysis on three outcomes which are disease severity, dengue serotype and disease infection type. Thirty studies with 3316 patients were included. Our analysis revealed that viremia is significantly higher in dengue hemorrhagic fever patients than dengue fever in days 5 to 6. Regarding the serotype of dengue, the maximum viremia titre of serotype 1 was significantly higher than serotype 3 and the viremia in dengue serotype 2 was significantly higher than serotype 4 in days 2 to 4. However, comparison of the daily viremia level between the primary and secondary dengue infection revealed that secondary infection was significantly higher than the primary infection on seventh day and on the eighth day. Viremia is strongly associated with disease severity and type of infection which gave viremia a high indicative power to be used as a clinical predictor. Dengue serotype is also associated with viral load with higher viremia in DENV‐2/1.
Comparative analysis of the genome structure and organization of the Middle East respiratory syndrome coronavirus (MERS‐CoV) 2012 to 2019 revealing evidence for virus strain barcoding, zoonotic transmission, and selection pressure
Authors: Ba Abduallah Mohamed M. , Hemida Maged Gomaa
Published: August 2020

The Middle East respiratory syndrome coronavirus (MERS‐CoV) emerged in late 2012 in Saudi Arabia. For this study, we conducted a large‐scale comparative genome study of MERS‐CoV from both human and dromedary camels from 2012 to 2019 to map any genetic changes that emerged in the past 8 years. We downloaded 1309 submissions, including 308 full‐length genome sequences of MERS‐CoV available in GenBank from 2012 to 2019. We used bioinformatics tools to describe the genome structure and organization of the virus and to map the most important motifs within various regions/genes throughout the genome over the past 8 years. We also monitored variations/mutations among these sequences since its emergence. Our phylogenetic analyses suggest that the cluster within African camels is derived by S gene. We identified some prominent motifs within the ORF1ab, S gene and ORF‐5, which may be used for barcoding the African camel lineages of MERS‐CoV. Furthermore, we mapped some sequence patterns that support the zoonotic origin of the virus from dromedary camels. Other sequences identified selection pressures, particularly within the N gene and the 5′ UTR. Further studies are required for careful monitoring of the MERS‐CoV genome to identify any potential significant mutations in the future.
Vitamin D and Covid‐19: From potential therapeutic effects to unanswered questions
Authors: Teymoori‐Rad Majid , Marashi Sayed Mahdi
Published: August 2020

Evidence suggests that vitamin D supplementation could potentially be effective either in treatment or prevention of coronavirus disease 2019 (Covid‐19). Indeed, several studies and trials have begun to investigate the impact of vitamin D supplementation on patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. In this review, we focus on the potential mechanisms of vitamin D in the pathogenesis of Covid‐19. We consider whether deficiency of vitamin D may be one of the underlying biological factors that could explain the excess mortality seen among non‐Caucasians. We also raise several important questions which need to be addressed to provide a clear picture of the extent to which vitamin D supplementation may benefit patients with Covid‐19, particularly those with underlying risk factors.
Stability analysis of positive switched impulsive systems with delay on time scales
Authors: Lu Xiaodong , Li Haitao , Wang Chuankui , Zhang Xianfu
Published: August 2020

In this paper, stability analysis of positive switched impulsive systems with delay on time scales is investigated. Firstly, a necessary and sufficient condition is provided for positivity of the considered systems. Secondly, by respectively considering the situations that the switching behavior and the impulsive phenomenon happen simultaneously and asynchronously, the uniformly asymptotical stability problems are addressed. Then, based on the linear copositive Lyapunov‐Krasovskii functional technique, two less conservative stability criteria are proposed. It are shown that these two criteria allow the time‐scale derivative of related Lyapunov functionals to be non‐negative at some intervals. Moreover, these two criteria are effective for not only continuous cases and discrete cases, but also some other positive switched impulsive systems on general uniform or hybrid time domains. Finally, a non‐continuous and non‐discrete example is given to illustrate the effectiveness of the theoretic results.
Consider technology that helps promote social distancing
Authors: Hope Joan
Published: August 2020

How can campuses reopen safely in the fall? That's a big question officials at many institutions are trying to answer. One key is to enable and encourage social distancing on campus. Officials at Apogee and Degree Analytics have partnered to create a solution that enables campus officials to track where people are gathering. Heat map displays show how many people are in an area.
Global view came easy for this well‐traveled leader
Authors: Enos Gary
Published: August 2020

Costas Solomou credits his upbringing and educational background for nurturing a lifelong appreciation of the global perspective. A first‐generation college student whose parents emigrated from Cyprus when he was a child, Solomou has long seen the value of a university campus as a global melting pot. He has served since 2019 as Vice President of Enrollment Management at the State University of New York at Geneseo, relocating from his most recent position as Dean of Admissions at George Washington University.
Assessing the efficacy of group model building workshops in an applied setting through purposive text analysis
Authors: Valcourt Nicholas , Walters Jeffrey , Javernick‐Will Amy , Linden Karl
Published: August 2020

Group model building (GMB) approaches have been shown to improve participants' understanding of complexity by shifting and aligning individuals' mental models of the interconnections within complex systems. However, reviews of GMB literature have identified knowledge gaps for assessing the efficacy of GMB activities. To address these gaps, these studies recommend assessing multiple cases, shifting from controlled to applied settings, and reporting on objective measures. We address each of these items by comparing the outputs of multiple community‐based GMB workshops to participants' mental models elicited through pre‐workshop interviews. Using purposive text analysis, we developed causal loop diagrams for comparison to a group workshop model. Through a quantitative analysis, we find that individuals convened in GMB workshops have greater alignment on factors, causal links, and feedback. We believe these contributions can help other GMB practitioners better assess the efficacy of their activities with more rigor and detail.

© 2020 System Dynamics Society
Encapsulation of Sulfur into N‐Doped Porous Carbon Cages by a Facile, Template‐Free Method for Stable Lithium‐Sulfur Cathode
Authors: Zeng Shuaibo , Arumugam Gowri Manohari , Liu Xianhu , Yang Yuzhao , Li Xin , Zhong Hai , Guo Fei , Mai Yaohua
Published: August 2020

Lithium‐sulfur (Li‐S) batteries with a high energy density and long lifespan are considered as promising candidates for next‐generation electrochemical energy‐storage devices. However, the sluggish redox kinetics of electrochemistry and high solubility of polysulfide during cycling render insufficient sulfur utilization and poor cycling stability. Herein, a facile, template‐free procedure based on controlled pyrolysis of polydopamine vesicles is described to prepare N‐doped porous carbon cages (NHSC) as a new sulfur host, which significantly improves both the sulfur utilization and cycling stability. As NHSC shows a high pore volume, continuous electron and ion transport paths, and good catalytic activity, encapsulation of S nanoparticles into NHSC endows the resulting S@NHSC electrode with a good energy storage capacity and exceptionally high electrochemical stability. Consequently, a Li‐S cell with the S@NHSC as the cathode achieves a high initial capacity of 1280.7 mAh g−1, and cycling stability over 500 cycles with the capacity decay as low as 0.0373% per cycle.
Zeolite Nanosheets Stabilize Catalyst Particles to Promote the Growth of Thermodynamically Unfavorable, Small‐Diameter Carbon Nanotubes
Authors: Carpena‐Núñez Jennifer , Rao Rahul , Kim Donghun , Bets Ksenia V. , Zakharov Dmitri N. , Boscoboinik J. Anibal , Stach Eric A. , Yakobson Boris I. , Tsapatsis Michael , Stacchiola Dario , Maruyama Benji
Published: August 2020

A challenge in the synthesis of single‐wall carbon nanotubes (SWCNTs) is the lack of control over the formation and evolution of catalyst nanoparticles and the lack of control over their size or chirality. Here, zeolite MFI nanosheets (MFI‐Ns) are used to keep cobalt (Co) nanoparticles stable during prolonged annealing conditions. Environmental transmission electron microscopy (ETEM) shows that the MFI‐Ns can influence the size and shape of nanoparticles via particle/support registry, which leads to the preferential docking of nanoparticles to four or fewer pores and to the regulation of the SWCNT synthesis products. The resulting SWCNT population exhibits a narrow diameter distribution and SWCNTs of nearly all chiral angles, including sub‐nm zigzag (ZZ) and near‐ZZ tubes. Theoretical simulations reveal that the growth of these unfavorable tubes from unsupported catalysts leads to the rapid encapsulation of catalyst nanoparticles bearing them; their presence in the growth products suggests that the MFI‐Ns prevent nanoparticle encapsulation and prologue ZZ and near‐ZZ SWCNT growth. These results thus present a path forward for controlling nanoparticle formation and evolution, for achieving size‐ and shape‐selectivity at high temperature, and for controlling SWCNT synthesis.
Nanoparticles in the Biological Context: Surface Morphology and Protein Corona Formation
Authors: Richtering Walter , Alberg Irina , Zentel Rudolf
Published: August 2020

A recent paper demonstrated that the formation of a protein corona is not a general property of all types of nanosized objects. In fact, it varies between a massive aggregation of plasma proteins onto the nanoparticle down to traces (e.g., a few proteins per 10 nanoparticles), which can only be determined by mass spectrometry in comparison to appropriate negative controls and background subtraction. Here, differences between various types of nanosized objects are discussed in order to determine general structure–property‐relations from a physico‐chemical viewpoint. It is highlighted that “not all nanoparticles are alike” and shown that their internal morphology, especially the difference between a strongly hydrated/swollen shell versus a sharp “hard” surface and its accessibility, is most relevant for biomedical applications.
Combined Tumor Environment Triggered Self‐Assembling Peptide Nanofibers and Inducible Multivalent Ligand Display for Cancer Cell Targeting with Enhanced Sensitivity and Specificity
Authors: Chen Weike , Li Shuxin , Lang John C. , Chang Yan , Pan Zui , Kroll Peter , Sun Xiankai , Tang Liping , Dong He
Published: August 2020

Many new technologies, such as cancer microenvironment‐induced nanoparticle targeting and multivalent ligand approach for cell surface receptors, are developed for active targeting in cancer therapy. While the principle of each technology is well illustrated, most systems suffer from low targeting specificity and sensitivity. To fill the gap, this work demonstrates a successful attempt to combine both technologies to simultaneously improve cancer cell targeting sensitivity and specificity. Specifically, the main component is a targeting ligand conjugated self‐assembling monomer precursor (SAM‐P), which, at the tumor site, undergoes tumor‐triggered cleavage to release the active form of self‐assembling monomer capable of forming supramolecular nanostructures. Biophysical characterization confirms the chemical and physical transformation of SAM‐P from unimers or oligomers with low ligand valency to supramolecular assemblies with high ligand valency under a tumor‐mimicking reductive microenvironment. The in vitro fluorescence assay shows the importance of supramolecular morphology in mediating ligand–receptor interactions and targeting sensitivity. Enhanced targeting specificity and sensitivity can be achieved via tumor‐triggered supramolecular assembly and induces multivalent ligand presentation toward cell surface receptors, respectively. The results support this combined tumor microenvironment‐induced cell targeting and multivalent ligand display approach, and have great potential for use as cell‐specific molecular imaging and therapeutic agents with high sensitivity and specificity.
Fabrication of a Robust PEM Water Electrolyzer Based on Non‐Noble Metal Cathode Catalyst: [Mo3S13]2− Clusters Anchored to N‐Doped Carbon Nanotubes
Authors: Holzapfel Peter K. R. , Bühler Melanie , Escalera‐López Daniel , Bierling Markus , Speck Florian D. , Mayrhofer Karl J. J. , Cherevko Serhiy , Pham Chuyen V. , Thiele Simon
Published: August 2020

High investment costs and a dependence on noble metal catalysts currently obstruct the large‐scale implementation of proton exchange membrane water electrolyzers (PEMWEs) for converting fluctuating green electricity into chemical energy via water splitting. In this context, this work presents a high‐performing and stable non‐noble metal catalyst for the hydrogen evolution reaction (HER), consisting of [Mo3S13]2− clusters supported on nitrogen doped carbon nanotubes (NCNTs). Strikingly, a significant electrochemically induced activation of the Mo3S13‐NCNT catalyst at high current densities is observed in full cell configuration, enabling a remarkable current density of 4 A cm−2 at a cell voltage of 2.36 V. To the authors’ knowledge, this is the highest reported value to date for a PEMWE full cell using a non‐noble metal HER catalyst. Furthermore, only a minor degradation of 83 µV h−1 is observed during a stability test of 100 h constant current at 1 A cm−2, with a nearly unchanged polarization behavior after the current hold. Catalyst stability and activity are additionally analyzed via online dissolution measurements. X‐ray photoelectron spectroscopy examination of the catalyst before and after electrochemical application reveals a correlation between the electrochemical activation occurring via electrodissolution with changes in the molecular structure of the Mo3S13‐NCNT catalyst.
A Biomimetic Polymer Magnetic Nanocarrier Polarizing Tumor‐Associated Macrophages for Potentiating Immunotherapy
Authors: Liu Lingqiao , Wang Yi , Guo Xing , Zhao Jingya , Zhou Shaobing
Published: August 2020

The progress of antitumor immunotherapy is usually limited by tumor‐associated macrophages (TAMs) that account for the highest proportion of immunosuppressive cells in the tumor microenvironment, and the TAMs can also be reversed by modulating the M2‐like phenotype. Herein, a biomimetic polymer magnetic nanocarrier is developed with selectively targeting and polarizing TAMs for potentiating immunotherapy of breast cancer. This nanocarrier PLGA‐ION‐R837 @ M (PIR @ M) is achieved, first, by the fabrication of magnetic polymer nanoparticles (NPs) encapsulating Fe3O4 NPs and Toll‐like receptor 7 (TLR7) agonist imiquimod (R837) and, second, by the coating of the lipopolysaccharide (LPS)‐ treated macrophage membranes on the surface of the NPs for targeting TAMs. The intracellular uptake of the PIR @ M can greatly polarize TAMs from M2 to antitumor M1 phenotype with the synergy of Fe3O4 NPs and R837. The relevant mechanism of the polarization is deeply studied through analyzing the mRNA expression of the signaling pathways. Different from previous reports, the polarization is ascribed to the fact that Fe3O4 NPs mainly activate the IRF5 signaling pathway via iron ions instead of the reactive oxygen species‐induced NF‐κB signaling pathway. The anticancer effect can be effectively enhanced through potentiating immunotherapy by the polarization of the TAMs in the combination of Fe3O4 NPs and R837.
Tin Nanodots Derived From Sn2+/Graphene Quantum Dot Complex as Pillars into Graphene Blocks for Ultrafast and Ultrastable Sodium‐Ion Storage
Authors: Liu Zheng , Zhang Su , Qiu Zhipeng , Huangfu Chao , Wang Lin , Wei Tong , Fan Zhuangjun
Published: August 2020

Tin (Sn) is considered to be an ideal candidate for the anode of sodium ion batteries. However, the design of Sn‐based electrodes with maintained long‐term stability still remains challenging due to their huge volume expansion (≈420%) and easy pulverization during cycling. Herein, a facile and versatile strategy for the synthesis of nitrogen‐doped graphene quantum dot (GQD) edge‐anchored Sn nanodots as the pillars into reduced graphene oxide blocks (NGQD/Sn‐NG) for ultrafast and ultrastable sodium‐ion storage is reported. Sn nanodots (2–5 nm) anchored at the edges of “octopus‐like” GQDs via covalent SnOC/SnNC bonds function as the pillars that ensure fast Na‐ion/electron transport across the graphene blocks. Moreover, the chemical and spatial (layered structure) confinements not only suppress Sn aggregation, but also function as physical barriers for buffering volume change upon sodiation/desodiation. Consequently, the NGQD/Sn‐NG with high structural stability exhibits excellent rate performance (555 mAh g−1 at 0.1 A g−1 and 198 mAh g−1 at 10 A g−1) and ultra‐long cycling stability (184 mAh g−1 remaining even after 2000 cycles at 5 A g−1). The confinement‐induced synthesis together with remarkable electrochemical performances should shed light on the practical application of highly attractive tin‐based anodes for next generation rechargeable sodium batteries.
Shear fatigue of prestressed I‐beams with shear reinforcement
Authors: Hillebrand Matthias , Teworte Frederik , Hegger Josef
Published: August 2020

In the last decades, increasing traffic loads have led to higher requirements on the bearing capacity of existing and also new bridges. In particular, many bridge structures built in the 1960s and 1970s often contain less web reinforcement than the nowadays required minimum web reinforcement. In this context, the shear resistance under cyclic loading is of special interest. For this reason, experimental tests were conducted on prestressed concrete beams with and without shear reinforcement at the Institute of Structural Concrete of RWTH Aachen University within the last years to investigate the shear fatigue strength. The specimens were able to resist more load cycles than predicted by the approaches implemented in the Eurocodes for bridges. Based on the test results, design models for shear under cyclic loading should be reviewed and improved, especially with regard to the assessment of existing structures. This paper describes the recent tests on 20 I‐shaped prestressed beams with web reinforcement.
Capitulum compartmentalization in Leucheria (Nassauvieae): Insights into the evolution of Asteraceae inflorescence
Authors: Katinas Liliana , Forte Noelia B.
Published: August 2020

An unusual feature occurs in the capitula of Leucheria (Nassauvieae, Asteraceae), some phyllaries of the involucre are twisted and/or rotated. The different spatial orientations of these phyllaries, called here paleaceous phyllaries, divide the capitulum into compartments enclosing florets and fruits. Because the internal morphology of the phyllaries could play a role in the compartmentalization, the anatomy of the phyllaries together with their different spatial arrangements was analyzed in the 49 species of Leucheria. We found differences between the abaxial and adaxial epidermis, bulliform‐like cells in the epidermis, and a callus at the base of the phyllaries. Cohesion, swelling, and turgor mechanisms in tissues are proposed to play a role in the positional changes of the phyllaries. The phyllaries bend, twist, rotate, and spread down and, excepting the latter, all are involved in capitula compartmentalization. The paleaceous phyllaries are already present in buds and continue during the whole plant life. Our results support previous phylogenetic hypotheses that suggest that Leucheria achieved a regular capitulum but maintained the remnants of an ancestor's pseudocephalium.
A merry host makes bolder guests: An analysis of cross‐border investment choices of Chinese firms
Authors: Soloveva Daria , Yamini Reza , Wei Jiuchang
Published: August 2020

This article explores the influence of a host country's conditions on foreign equity investment decisions made by China‐based firms using the assumptions of the institutional theory and transaction cost approach. We use multinomial logit regression to analyze a sample of 1,018 cross‐border investments by Chinese firms categorized into majority acquisitions, minority acquisitions, joint ventures (JVs), and venture capital. According to our findings, Chinese investors prefer to conduct foreign direct investment in the same industry. This, in turn, highlights their desire to gain market influence and learn or obtain strategic knowledge and resources. Furthermore, taxation is proved to encourage the establishment of foreign JVs. The interaction between the host country's tax levels and majority acquisitions in the same industry reveals the concern of Chinese investors with after‐tax returns and influence in the new market.
Bringing Bilingualism to the Center of Guided Reading Instruction
Authors: Ascenzi‐Moreno Laura , Quiñones Rebecca
Published: August 2020

Educators consider guided reading one of the most powerful instructional tools in a reading teacher’s arsenal. Yet, when it comes to emergent bilinguals in both monolingual English and bilingual settings, guided reading is implemented monolingually, or in one language at a time. As the field of reading instruction has moved toward a more asset‐based take on students’ bilingualism, integrating a bilingual approach to guided reading is necessary. The authors offer educators a lens to understand how emergent bilinguals’ resources and bilingualism can be incorporated into guided reading, along with concrete examples that can assist teachers in enacting these practices in their classrooms.
COVID‐19 during pregnancy: non‐reassuring fetal heart rate, placental pathology and coagulopathy
Authors: Mongula J. E. , Frenken M. W. E. , van Lijnschoten G. , Arents N. L. A. , de Wit‐Zuurendonk L. D. , Schimmel‐de Kok A. P. A. , van Runnard Heimel P. J. , Porath M. M. , Goossens S. M. T. A.
Published: August 2020

We report a case of a pregnant woman with COVID‐19 who developed coagulopathy in the absence of severe clinical symptoms. A polymerase chain reaction test of a vaginal swab was positive for SARS‐CoV‐2 RNA, suggesting a possibility of perinatal transmission. Cesarean delivery was performed because of a non‐reassuring fetal heart rate; the placenta showed increased perivillous fibrin deposition and intervillositis. Moreover, placental infection with SARS‐CoV‐2 was demonstrated by placental immunostaining. The findings suggest a possible relationship between placental fibrin deposition and chronic and acute intervillositis, non‐reassuring fetal heart rate and coagulopathy in pregnant women with COVID‐19. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Vakuumkomponenten aus Aluminium für UHV und XHV
Authors: Bergner Ute , Biethahn Maximilian , Worsch Christian , Flämmich Michael , Bergner Klaus
Published: August 2020

Die mechanische Festigkeit von 6000er Al‐Legierungen ist ausreichend, um stabile CF‐Schneidkanten herzustellen. Wichtig ist dabei, dass im Verarbeitungsprozess und in der Anwendung die Materialhöchsttemperaturen zum Erhalt der notwendigen mechanischen Festigkeit nicht überschritten werden. In Messreihen zur Schneidkantengeometrie konnte die Eignung dieser Aluminiumlegierungen für den Einsatz im UHV und XHV nachgewiesen werden. Darüber hinaus erklärt der Beitrag, wie reproduzierbare Prozessbedingungen beim Schweißen die Fertigung vaku‐umdichter Schweißnähte mit sauberer Wurzelbildung sicherstellen, wobei spezielle Schweißparametern sicherstellen, dass beim Schweißprozess im Schneidkantenbereich die kritischen Temperaturen nicht überschritten werden.

Vergleichsmessungen an Aluminium‐ und Edelstahlkammern zeigen, dass mit Aluminium als Werkstoff in kürzerer Zeit und – aufgrund niedrigerer Ausheiztemperaturen – mit geringerem Energieaufwand UHV‐Bedingungen erreicht werden.
Perspectives on liquid biopsy for label‐free detection of “circulating tumor cells” through intelligent lab‐on‐chips
Authors: Miccio Lisa , Cimmino Flora , Kurelac Ivana , Villone Massimiliano M. , Bianco Vittorio , Memmolo Pasquale , Merola Francesco , Mugnano Martina , Capasso Mario , Iolascon Achille , Maffettone Pier Luca , Ferraro Pietro
Published: August 2020

Circulating tumor cells (CTCs) are rare tumor cells released from primary, metastatic, or recurrent tumors in the peripheral blood of cancer patients. CTCs isolation from peripheral blood and their molecular characterization represent a new marker in cancer screening, a diagnostic tool called “liquid biopsy” (LB). Compared to traditional tissue biopsy that is invasive and does not reveal tumor heterogeneity, LB is noninvasive and reflects in “real‐time” tumor dynamism and drug sensitivity. In the frame of LB, a new paradigm based on single‐cell and label‐free analysis based on morphological analysis is emerging. Here, we review the latest research developments in this emerging vision of LB. In particular, we survey and discuss recent improvements in microfluidics, imaging label‐free diagnosis and cell classification by artificial intelligence and how to combine them to realize an intelligent platform based on lab‐on‐chip technology. This prospect appears to open up promising and intriguing new scenarios for cancer management through single‐cell analysis that will revolutionize the future of early cancer diagnosis and therapeutic choice with disruptive impact on the society.
Black phosphorus: Versatile two‐dimensional materials in cancer therapies
Authors: Ding Jie , Qu Guangbo , Chu Paul K. , Yu Xue‐Feng
Published: August 2020

Black phosphorus (BP) constitutes a new class of two‐dimensional materials with multiple biomedical functionalities and applications. Possessed with outstanding advantages of large surface area, intrinsic photoacoustic properties, excellent biocompatibility, and selective toxicity to tumor cells, BP is becoming an ideal candidate in multifunctional cancer theranostics including photothermal therapy, photodynamic therapy, drug delivery, and bioactive phosphotherapy. This minireview summarizes recent progress pertaining to theranostic applications of BP nanosheets and black phosphorus quantum dots and discusses the prospects in advanced theranostics.
Traumatic reticuloperitonitis combined with embolic pneumonia and hepatitis as unusual symptoms of foreign body syndrome in a Holstein bull
Authors: de Souza Verônica L. , Pinto Arthur M. S. V. , Queiroz Cintia R. R. , de Castro Márcio B. , Borges José R. J. , Soto‐Blanco Benito , Câmara Antônio C. L.
Published: August 2020

Traumatic reticuloperitonitis combined with embolic pneumonia and hepatitis is unusual signs of foreign body syndrome in cattle. A 4‐year‐old Holstein bull presented decreased appetite, dry cough, progressive weight loss, sternal recumbence and reluctance to stand and move. Laboratory tests revealed leucocytosis (18.4 × 103/μl) accompanied by neutrophilia (10.48 × 103/μl), and monocytosis (1.28 × 103/μl), hyperglobulinaemia (6.3 g/dl), hypoalbuminaemia (1.5 g/dl), hyperfibrinogenaemia (10 g/L) and severe increase in gamma‐glutamyl transferase activity (1,216 U/L). Reticular ultrasonographical examination showed a large amount of hyperechoic and hypoechoic content between the reticular serosa and the hepatic visceral surface. The main gross findings included fibrin deposition and adhesions between the reticulum, liver and diaphragm surfaces; a 4.0 mm in diameter transmural reticular perforation; a 12.0‐cm diameter and scarce small randomly abscesses in the liver's parenchyma. The lungs presented multifocal areas of suppurative embolic foci (pulmonary abscesses), interstitial emphysema and multifocal fibrin deposition on the pleural surface. Ancillary diagnostic tests, such as ultrasonography and laboratory test, associated with clinical evaluation, may increase the accuracy of the correct diagnosis and avoid wasting time and money on untreatable cases.
Coping strategies for individual and household‐level water insecurity: A systematic review
Authors: Venkataramanan Vidya , Collins Shalean M. , Clark Kathleen A. , Yeam Julia , Nowakowski Virginia G. , Young Sera L.
Published: August 2020

Household water insecurity is a complex socioecological challenge with a range of consequences for health and wellbeing. Understanding individual and household‐level coping strategies, i.e., responses or adaptations to manage water insecurity, can shape future research and development practice. We therefore (a) systematically describe the characteristics and contexts of 173 studies documenting coping strategies and (b) classify the types of strategies within four domains of water insecurity: access, use, quality, and reliability. Most studies were from Sub‐Saharan Africa or South Asia. In the domain of access, the most common coping strategies were building infrastructure, and storing, purchasing, and sharing water. For use, changing food consumption, agricultural practices, and hygiene were most frequently mentioned. For quality, water treatment was the most common strategy. To ensure water reliability, people most frequently reported changing routines or relocating their homes altogether. Our review provides a useful framework to understand coping strategies, but more research is needed to address three gaps in particular. First, we recommend more representative exploration of the range of coping strategies, particularly in middle‐ and high‐income countries. Second, the links between coping with water insecurity and a range of other nutritional, social, financial, and health outcomes need to be better understood to address overall household wellbeing. Third, we recommend the development of a metric to quantify individual and household‐level water insecurity‐related coping strategies. This line of inquiry can enable practitioners to design and implement context‐specific interventions that leverage preexisting strategies to improve experiences of water insecurity.

This article is categorized under:

Human Water > Water Governance

Engineering Water > Planning Water
CFD simulations and evaluation of applicability of a wall roughness model applied on a NACA 633‐418 airfoil
Authors: Kruse Emil Krog , Sørensen Niels , Bak Christian , Nielsen Mikkel Schou
Published: August 2020

The implementation of a model to simulate distributed surface roughness, which is the new k−ω extension by Knopp et al. into the DTU Wind Energy in‐house CFD Reynolds‐Average Naviar Stokes solver EllipSys, was validated against wind tunnel experiments conducted in the Laminar Wind Tunnel of the Institute of Aerodynamics and Gas Dynamics, University of Stuttgart. The effort was to predict the aerodynamic penalty of five cases of leading edge roughness applied to a NACA 633‐418. Three cases were sandpaper, and two cases were turbulators/zigzag tape. Simulation of the sandpaper cases showed some agreement in the tendencies of decreased lift and increased drag as a function of angle of attack. However, the magnitudes of the aerodynamic changes were predicted and underestimated the lift and overestimated the drag. Modeling the zigzag tape using the roughness model was not successful, because the influence from the model was too small. The simulated zigzag tape hardly deviated from the fully turbulent simulation, so when using the model in its current form, one should be aware of its limitations.
A nonlinear inverse model for airborne wind energy system analysis, control, and design optimization
Authors: Aull Mark , Cohen Kelly
Published: August 2020

This paper describes a nonlinear model inversion for performance analysis and system optimization for airborne wind energy (AWE) systems. Airborne wind energy systems are lighter and potentially lower in cost than comparable conventional wind turbines due to using a tether and bridle rather than blades and a tower which must support high bending and compressive loads. They are also easier to install due to using a tension anchor rather than a foundation. There are many AWE systems in various states of R&D, but no commercial AWE wind farms currently exist. Because AWE systems are novel and significantly more complex to design, analyze, and test than conventional wind turbines, better analysis tools are important for the technology to mature.

AWE system design involves many interdependent design trade‐offs, which are difficult to analyze with traditional tools; using simulations to iterate through parameters for design optimization is undesirable. A nonlinear model inversion based on appropriate simplifying assumptions is better suited to this task. The inverse model uses a trajectory input then calculates attitudes, forces, and control values required to follow that trajectory as well as power produced. Applicable constraints ensure that the trajectory is realizable. A validation is presented, using the output of the inverse model as a feed‐forward controller for a high fidelity simulation. The analysis shows good agreement with the simulation, despite simplifications such as a straight rigid tether, constant lift and drag coefficients, and a simplified rotor model.