bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth hormone receptor promotes breast cancer progression via the BRAF/MEK/ERK signaling pathway
Authors: Zhu Xiaojue , Li Yonghao , Xu Guoxin , Fu ChangQing
Published: February 2020

Growth hormone receptor (GHR), a member of the class I cytokine receptor family, plays key roles in cancer progression. Recently, GHR has been reported to be associated with breast cancer development, but the molecular mechanism of GHR in this malignancy is not fully understood. To investigate this issue, we stably inhibited GHR in breast cancer cell lines, which were observed to reduce cell proliferation, tumor growth and induction of apoptosis, and arrest the cell‐cycle arrest at the G1–S phase transition. In addition, GHR silencing suppressed the protein levels of B‐Raf proto‐oncogene, serine/threonine kinase (BRAF), Mitogen‐activated protein kinase kinase (MEK) and Extracellular regulated protein kinases (ERK). These findings suggest that GHR may mediate breast cell progression and apoptosis through control of the cell cycle via the BRAF/MEK/ERK signaling pathway.
Retracted: Mechanical Properties and Energy Absorption Capability of ARCH Lattice Structures Manufactured by Selective Laser Melting
Authors: Ding Ruochen , Yao Jun , Du Baorui , Zhao Lu , Guo Yumeng
Published: February 2020

Selective laser melting (SLM) is widely used in lattice structure manufacturing. ARCH lattice structure is named ARCH because the center line of ARCH strut is arched; compared with other structures, arch can afford bigger pressure. Herein, the ARCH lattice structures are analyzed by finite element analysis, and the stress distribution of the ARCH lattice structures is obtained. The quasistatic compression experiment is conducted on the ARCH lattice structure samples. The mechanical properties and energy absorption capability of ARCH lattice structures with different relative densities fabricated by SLM are experimentally researched. The results show that, compared with other lattice structures, ARCH lattice structures have superior mechanical properties and energy absorption capability. The relative density has a great influence on the mechanical properties and energy absorption capability of ARCH lattice structures. The Gibson–Ashby equation is also established to estimate the mechanical properties and energy absorption capability of the lattice structures with different relative densities.
Light‐Emitting Electrochemical Cells Based on Color‐Tunable Inorganic Colloidal Quantum Dots
Authors: Nannen Ekaterina , Frohleiks Julia , Gellner Sandra
Published: February 2020

Large‐area, ultrathin light‐emitting devices currently inspire architects and interior and automotive designers all over the world. Light‐emitting electrochemical cells (LECs) and quantum dot light‐emitting diodes (QD‐LEDs) belong to the most promising next‐generation device concepts for future flexible and large‐area lighting technologies. Both concepts incorporate solution‐based fabrication techniques, which makes them attractive for low cost applications based on, for example, roll‐to‐roll fabrication or inkjet printing. However, both concepts have unique benefits that justify their appeal. LECs comprise ionic species in the active layer, which leads to the omission of additional organic charge injection and transport layers and reactive cathode materials, thus LECs impress with their simple device architecture. QD‐LEDs impress with purity and opulence of available colors: colloidal quantum dots (QDs) are semiconducting nanocrystals that show high yield light emission, which can be easily tuned over the whole visible spectrum by material composition and size. Emerging technologies that unite the potential of both concepts (LEC and QD‐LED) are covered, either by extending a typical LEC architecture with additional QDs, or by replacing the entire organic LEC emitter with QDs or perovskite nanocrystals, still keeping the easy LEC setup featured by the incorporation of mobile ions.
Piezoelectric Nano‐Biomaterials for Biomedicine and Tissue Regeneration
Authors: Kapat Kausik , Shubhra Quazi T. H. , Zhou Miao , Leeuwenburgh Sander
Published: February 2020

Among various classes of biomaterials, the majority of non‐centrosymmetric crystalline materials exhibit piezoelectric properties, i.e., the accumulation of charge in response to applied mechanical stress or deformation. Due to the growing interest in nanomaterials, piezoelectric nano‐biomaterials have been widely investigated, leading to remarkable advancements throughout the last two decades. Piezoelectric properties, high surface energy, targeting properties, and intricate cell–material interactions render piezoelectric nanomaterials highly attractive for application in therapeutics as well as regenerative medicine. Herein, the major focus is to highlight the wide range of applications of piezoelectric nano‐biomaterials in drug delivery, theranostics, and tissue regeneration. After a brief introduction to piezoelectricity, an overview is provided on the major classes of piezoelectric biomaterials as well as a description of the origin of biopiezoelectricity in different tissues and macromolecules. Subsequently, relevant properties and postfabrication strategies of nanostructured piezoelectric biomaterials are discussed aiming to maximize piezoresponse. Finally, recent studies on nano‐ piezoceramics and piezopolymers are presented, with specific focus on barium titanate, zinc oxide, and polyvinylidene fluoride.
Rational Molecular Design of Benzoquinone‐Derived Cathode Materials for High‐Performance Lithium‐Ion Batteries
Authors: Yang Jixing , Xiong Peixun , Shi Yeqing , Sun Pengfei , Wang Zhuanping , Chen Zifeng , Xu Yunhua
Published: February 2020

p‐Benzoquinone (BQ) is a promising cathode material for lithium‐ion batteries (LIBs) due to its high theoretical specific capacity and voltage. However, it suffers from a serious dissolution problem in organic electrolytes, leading to poor electrochemical performance. Herein, two BQ‐derived molecules with a near‐plane structure and relative large skeleton: 1,4‐bis(p‐benzoquinonyl)benzene (BBQB) and 1,3,5‐tris(p‐benzoquinonyl)benzene (TBQB) are designed and synthesized. They show greatly decreased solubility as a result of strong intermolecular interactions. As cathode materials for LIBs, they exhibit high carbonyl utilizations of 100% with high initial capacities of 367 and 397 mAh g−1, respectively. Especially, BBQB with better planarity presents remarkably improved cyclability, retaining a high capacity of 306 mAh g−1 after 100 cycles. The cycling stability of BBQB surpasses all reported BQ‐derived small molecules and most polymers. This work provides a new molecular structure design strategy to suppress the dissolution of organic electrode materials for achieving high performance rechargeable batteries.
Tailored Amphiphilic Molecular Mitigators for Stable Perovskite Solar Cells with 23.5% Efficiency
Authors: Zhu Hongwei , Liu Yuhang , Eickemeyer Felix T. , Pan Linfeng , Ren Dan , Ruiz‐Preciado Marco A. , Carlsen Brian , Yang Bowen , Dong Xiaofei , Wang Zaiwei , Liu Hongli , Wang Shirong , Zakeeruddin Shaik M. , Hagfeldt Anders , Dar M. Ibrahim , Li Xianggao , Grätzel Michael
Published: February 2020

Passivation of interfacial defects serves as an effective means to realize highly efficient and stable perovskite solar cells (PSCs). However, most molecular modulators currently used to mitigate such defects form poorly conductive aggregates at the perovskite interface with the charge collection layer, impeding the extraction of photogenerated charge carriers. Here, a judiciously engineered passivator, 4‐tert‐butyl‐benzylammonium iodide (tBBAI), is introduced, whose bulky tert‐butyl groups prevent the unwanted aggregation by steric repulsion. It is found that simple surface treatment with tBBAI significantly accelerates the charge extraction from the perovskite into the spiro‐OMeTAD hole‐transporter, while retarding the nonradiative charge carrier recombination. This boosts the power conversion efficiency (PCE) of the PSC from ≈20% to 23.5% reducing the hysteresis to barely detectable levels. Importantly, the tBBAI treatment raises the fill factor from 0.75 to the very high value of 0.82, which concurs with a decrease in the ideality factor from 1.72 to 1.34, confirming the suppression of radiation‐less carrier recombination. The tert‐butyl group also provides a hydrophobic umbrella protecting the perovskite film from attack by ambient moisture. As a result, the PSCs show excellent operational stability retaining over 95% of their initial PCE after 500 h full‐sun illumination under maximum‐power‐point tracking under continuous simulated solar irradiation.
Engineering Multimetallic Aerogels for pH‐Universal HER and ORR Electrocatalysis
Authors: Du Ran , Jin Wei , Hübner René , Zhou Lin , Hu Yue , Eychmüller Alexander
Published: February 2020

The advent of noble metal aerogels (NMAs), that feature the high catalytic activity of noble metals and unique structural attributes of aerogels, has stimulated research on a new class of outstanding electrocatalysts. However, limited by the available compositions, the explored electrocatalytic reactions on NMAs are highly restricted and certain important electrochemical processes have not been investigated. Here, an effective gelation approach is demonstrated by using a strong salting‐out agent (i.e., NH4F), thereby expanding the composition of NMAs to various multimetallic systems and providing a platform to investigate composition‐dependent electrocatalytic performance of NMAs. Combining structural features of aerogels and optimized chemical compositions, the Au–Pt and Au–Rh aerogel catalysts manifest remarkable pH‐universal (pH = 0–14) performance surpassing commercial Pt/C and many other nanoparticle (NP)‐based catalysts in the electrocatalytic oxygen reduction reaction, hydrogen evolution reaction, and water splitting, displaying enormous potential for the electrochemical hydrogen production, fuel cells, etc.
A clinical evaluation and tissue fiber burden analysis of a lifetime resident of Libby, Montana with adenocarcinoma of the lung
Authors: Dodson Ronald F. , Black Brad , Poye Lee W. , Bruce James R. , McNew Tracy
Published: February 2020

Introduction

Vermiculite mining operations near Libby, Montana were active from the 1920s to 1990. Rail facilities for shipment of the mined material as well as some vermiculite processing activities were ongoing within the community of Libby. A fibrous component within the mined material has been associated with asbestos‐related diseases in vermiculite miners and in the local citizens of the community.

Clinical History/Methods

We present a clinical case history and tissue fiber burden analysis of an individual with a multifocal adenocarcinoma of the lung who was a lifelong resident of Libby and whose history of exposure was as a member of the general population there.

Results/Discussion

To our knowledge this is the first time tissue from a member of the general population of Libby, Montana has been evaluated and shown to contain an appreciable presence of “Libby amphibole” fibers.
Further delineation of METTL23‐associated intellectual disability
Authors: Almannai Mohammed , Obaid Osama , Faqeih Eissa , Alasmari Ali , Samman Manar M. , Pinz Hailey , Braddock Stephen R. , Alkuraya Fowzan S.
Published: February 2020

METTL23 belongs to a family of methyltransferase like proteins (METTL) that transfer methyl group to various substrates. Recently, pathogenic homozygous variants in METTL23 were identified in patients from three families who presented with intellectual disability (ID) and variable dysmorphic features. In this report, we present unpublished phenotypic data from the original family as well as six new subjects from four families who also presented with mild to moderate ID and dysmorphic features, and were found to harbor four previously unpublished homozygous or compound heterozygous variants in METTL23. Our report further supports the role of this gene in autosomal recessive ID and emphasizes the mild but consistent facial features.
Insights into Charge Transfer at an Atomically Precise Nanocluster/Semiconductor Interface
Authors: Wang Yu , Liu Xiao‐He , Wang Qiankun , Quick Martin , Kovalenko Sergey A. , Chen Qing‐Yun , Koch Norbert , Pinna Nicola
Published: February 2020

The deposition of an atomically precise nanocluster, for example, Ag44(SR)30, onto a large‐band‐gap semiconductor such as TiO2 allows a clear interface to be obtained to study charge transfer at the interface. Changing the light source from visible light to simulated sunlight led to a three orders of magnitude enhancement in the photocatalytic H2 generation, with the H2 production rate reaching 7.4 mmol h−1 gcatalyst−1. This is five times higher than that of TiO2 modified with Ag nanoparticles and even comparable to that of TiO2 modified with Pt nanoparticles under similar conditions. Energy band alignment and transient absorption spectroscopy reveal that the role of the metal clusters is different from that of both organometallic complexes and plasmonic nanoparticles: A type II heterojunction charge‐transfer route is achieved under UV/Vis irradiation, with the cluster serving as a small‐band‐gap semiconductor. This results in the clusters acting as co‐catalysts rather than merely photosensitizers.
Reaktionsmechanismen Lithium‐reicher Schicht‐Kathodenmaterialien für Hochenergie‐Lithium‐Ionenbatterien
Authors: Zhao Shuoqing , Yan Kang , Zhang Jinqiang , Sun Bing , Wang Guoxiu
Published: February 2020

Lithium‐reiche Schicht‐Kathodenmaterialien finden wegen ihrer hohen theoretischen spezifischen Kapazität (320–350 mA h g−1) großes Interesse. Schlechte Zyklenstabilität und träge Reaktionskinetik behindern aber ihre Anwendung. Nachdem sich die Wissenschaft lange von diesem Thema abgewendet hat, dürften nun wegen der starken Abhängigkeit von Hochenergie‐Li‐Ionenbatterien Forschung und Entwicklung im Bereich geschichteter Li‐reicher Kathodenmaterialien wieder stark zunehmen. In diesem Kurzaufsatz berichten wir über den Stand des Wissens zu Strukturanalyse und Reaktionsmechanismen speziell von Mangan‐basierten geschichteten Li‐reichen Kathodenmaterialen. Wir fassen dabei die Kationen‐Redoxreaktionen der Übergangsmetallionen und die Anionen‐Redoxreaktionen von Sauerstoffspezies detailliert zusammen. Abschließend diskutieren wir Möglichkeiten und Herausforderungen bei der zukünftigen Erforschung und Entwicklung Li‐reicher Kathodenmaterialien.
All‐polyethylene compositions based on ultrahigh molecular weight polyethylene: Synthesis and properties
Authors: Ushakova Tatiana M. , Starchak Elena E. , Gostev Sergey S. , Grinev Vitaly G. , Krasheninnikov Vadim G. , Gorenberg Arcady Ya. , Novokshonova Lyudmila A.
Published: February 2020

Reactor polymer compositions (RPC) of ultrahigh molecular weight polyethylene (UHMWPE) with Mw = 1,000 kg/mol and low molecular weight high density polyethylene (LMWPE) with Mw = 160 kg/mol were synthesized in a two‐stage ethylene polymerization with a rac‐Me2Si(Ind)2ZrCl2/methylaluminoxane catalyst. The conditions of the stages that ensure the formation of UHMWPE and LMWPE fractions with the desired molecular weight and properties were selected based on the study of one‐stage ethylene polymerization over this catalyst in a wide temperature range. The order of fraction synthesis in RPC preparation was changed. Two series of compositions UHMWPE/LMWPE and LMWPE/UHMWPE with UHMWPE content from 20 to 90 wt% were obtained. The SEM method was used to study the morphology of the nascent polymer particles. It was shown that RPC physical and mechanical properties depend not only on the UHMWPE content, but also on the morphology of the particles of reactor powders, which is determined by the order of polymer fraction synthesis. Materials of LMWPE/UHMWPE series have higher tensile properties compared to UHMWPE/LMWPE of the same composition. The LMWPE/UHMWPE compositions containing ≤50 wt% of UHMWPE flow even at a load of 10.5 kg.
Scalable Formation of Heterogeneous Agents considering Unknown Disturbances
Authors: Djamari Djati Wibowo
Published: February 2020

The problem considered in this work is formation control of linear heterogeneous Multi‐Agent Systems (MASs) where the size of the formation is scalable via a scaling factor determined by a leader agent. Agents are communicating through a leader‐follower time‐varying network and they are subjected to an unknown disturbances. Past works on scalable formation are limited to the case of homogeneous agents under fixed communication network and without considering disturbances. The control law in this work is based on the internal model principle and the
control theory. A dynamic compensator is designed based on the regular
output feedback problem and its output is used as the feedback signal in the main control input. Meanwhile, the main control input is designed based on the internal model principle. It is shown that the effect of the disturbance to the agent's output is minimized and the tracking error satisfies
performance. The effectiveness of the proposed method is shown by numerical examples.
Dye Adsorption on Plate‐like Nanocrystalline Bi2WO6 Synthesized by Microwave Hydrothermal Methods
Authors: Kim Young‐Jin , Nam Chunghee
Published: February 2020

The adsorption characteristics of the methylene blue (MB) dye on Bi2WO6 nanopowder, which was synthesized by the microwave‐assisted hydrothermal method, were studied. The structural and morphological properties of the Bi2WO6 sample were examined by scanning electron microscopy, transmission electron microscopy, and powder X‐ray diffraction. The change in the dye concentration with respect to the time of adsorption on the as‐prepared Bi2WO6 nanomaterial was measured by UV–visible spectrophotometry according to Beer–Lambert's law. The maximum adsorption capacity was determined by monitoring the change in the adsorption amount of MB in acidic or basic conditions (various pH). The Bi2WO6 nanomaterial showed excellent reusable properties after annealing at 300°C, which was performed to remove the adsorbed MB for recycling.
Indospicine combined with arginine deprivation triggers cancer cell death via caspase‐dependent apoptosis
Authors: Shuvayeva Galyna Y. , Bobak Yaroslav P. , Vovk Olena I. , Kunz‐Schughart Leoni A. , Fletcher Mary T. , Stasyk Oleh V.
Published: February 2020

Arginine‐deprivation therapy is a rapidly developing metabolic anticancer approach. To overcome the resistance of some cancer cells to this monotherapy, rationally designed combination modalities are needed. In this report, we evaluated for the first time indospicine, an arginine analogue ofIndigoferaplant genus origin, as potential enhancer compound for the metabolic therapy that utilizes recombinant human arginase I. We demonstrate that indospicine at low micromolar concentrations is selectively toxic for human colorectal cancer cells only in the absence of arginine. In arginine‐deprived cancer cells indospicine deregulates some prosurvival pathways (PI3K‐Akt and MAPK) and activates mammalian target of rapamycin, exacerbates endoplasmic reticulum stress and triggers caspase‐dependent apoptosis, which is reversed by the exposure to translation inhibitors. Simultaneously, indospicine is not degraded by recombinant human arginase I and does not inhibit this arginine‐degrading enzyme at its effective dose. The obtained results emphasize the potential of arginine structural analogues as efficient components for combinatorial metabolic targeting of malignant cells.
Balloon expandable covered stents for aortic injury: It's a thing
Authors: Parekh Dhaval R. , Krajcer Zvonimir
Published: February 2020

Key Points

The balloon expandable Cheatham Platinum (CP) covered stent can be successfully implanted in some older children with hemodynamically stable traumatic aortic injury.

The CP stents can be delivered via smaller sheaths and reexpanded over time as needed.

There were no reported complications, albeit in this small cohort of patients with hemodynamically stable traumatic aortic injury.

Continued advances in balloon expandable covered stent technology are needed to improve delivery profile, fixation and sealing zones, radial strength, and flexibility.
Impella ventricular assist device: A “valvular bypass” to support high‐risk percutaneous coronary intervention or complicated transcatheter aortic valve replacement
Authors: Tarantini Giuseppe , Nai Fovino Luca
Published: February 2020

Key Points

Severe aortic stenosis is usually considered a contraindication to the implantation of Impella ventricular assist device.

In the setting of pre‐transcatheter aortic valve replacement (TAVR), high‐risk percutaneous coronary intervention, Impella stabilizes hemodynamics by reducing left ventricular end‐diastolic pressure and increasing cardiac output and coronary perfusion.

The implantation of Impella was feasible for the treatment of cardiogenic shock occurring during TAVR. Nevertheless, 30‐day mortality remained as high as 40%.
Mechanical circulatory support in high‐risk percutaneous coronary intervention: IIb or not IIb?
Authors: Ayyoub Alaa , Levy Michael S.
Published: February 2020

Key Points

The use of percutaneous ventricular assist device (PVAD)‐assisted high‐risk percutaneous coronary intervention (HRPCI) is increasingly common.

When used in select patients, PVAD‐assisted HRPCI is a safe and effective alternative to intra‐aortic balloon pump.

Further high‐quality study is needed on this important subject.
An In‐Depth Mechanistic Study of Ru‐Catalysed Aqueous Methanol Dehydrogenation and Prospects for Future Catalyst Design
Authors: Govindarajan Nitish , Sinha Vivek , Trincado Monica , Grützmacher Hansjörg , Meijer Evert Jan , de Bruin Bas
Published: February 2020

Herein we provide mechanistic insights into the dehydrogenation of aqueous methanol catalysed by the [Ru(trop2dae)] complex (which is in‐situ generated from [Ru(trop2dad)], trop2dad=1,4‐bis(5H‐dibenzo[a,d]cyclohepten‐5‐yl)‐1,4‐diazabuta‐1,3‐diene), established by density functional theory based molecular dynamics (DFT‐MD) and static DFT calculations incorporating explicit solvent molecules. The aqueous solvent proved to participate actively in various stages of the catalytic cycle including the catalyst activation process, and the key reaction steps involving C−H activation and hydrogen production. The aqueous solvent forms an integral part of the reactive system for the C−H activation steps in the [Ru(trop2dae)] system, with strong hydrogen bond interactions with the anionic oxygen (RO−, R=CH3, CH2OH, HCO) and hydride moieties formed along the reaction pathway. In contrast to the [Ru(trop2dad)] catalyst, C−H activation and hydrogen production does not proceed via a metal‐ligand cooperative pathway for the [Ru(trop2dae)] system. The pKa of the coordinated amine donors in these complexes provides a rationale for the divergent reactivity, and the obtained mechanistic information provides new guidelines for the rational design of active and additive free catalytic systems for aqueous methanol dehydrogenation.
The postnatal development of MT, V1, LGN, pulvinar and SC in prosimian galagos (Otolemur garnettii)
Authors: Turner Emily C. , Gabi Mariana , Liao Chia‐Chi , Kaas Jon H.
Published: February 2020

Considerable evidence supports the premise that the visual system of primates develops hierarchically, with primary visual cortex developing structurally and functionally first, thereby influencing the subsequent development of higher cortical areas. An apparent exception is the higher order middle temporal visual area (MT), which appears to be histologically distinct near the time of birth in marmosets. Here we used a number of histological and immunohistological markers to evaluate the maturation of cortical and subcortical components of the visual system in galagos ranging from newborns to adults. Galagos are representative of the large strepsirrhine branch of primate evolution, and studies of these primates help identify brain features that are broadly similar across primate taxa. The histological results support the view that MT is functional at or near the time of birth, as is primary visual cortex. Likewise, the superior colliculus, dorsal lateral geniculate nucleus, and the posterior nucleus of the pulvinar are well‐developed by birth. Thus, these subcortical structures likely provide visual information directly or indirectly to cortex in newborn galagos. We conclude that MT resembles a primary sensory area by developing early, and that the early development of MT may influence the subsequent development of dorsal stream visual areas.
Complexes H2CO:PXH2and HCO2H : PXH2for X=NC, F, Cl, CN, OH, CCH, CH3, and H: Pnicogen Bonds and Hydrogen Bonds
Authors: Del Bene Janet E. , Alkorta Ibon , Elguero José
Published: February 2020

Ab initio MP2/aug’‐cc‐pVTZ calculations have been carried out to investigate H2CO : PXH2pnicogen‐bonded complexes and HCO2H : PXH2complexes that are stabilized by pnicogen bonds and hydrogen bonds, with X=NC, F, Cl, CN, OH, CCH, CH3, and H. The binding energies of these complexes exhibit a second‐order dependence on the O−P distance. DFT‐SAPT binding energies correlate linearly with MP2 binding energies. The HCO2H : PXH2complexes are stabilized by both a pnicogen bond and a hydrogen bond, resulting in greater binding energies for the HCO2H : PXH2complexes compared to H2CO : PXH2. Neither the O−P distance across the pnicogen bond nor the O−P distance across the hydrogen bond correlates with the binding energies of these complexes. The nonlinearity of the hydrogen bonds suggests that they are relatively weak bonds, except for complexes in which the substituent X is either CH3or H. The pnicogen bond is the more important stabilizing interaction in the HCO2H : PXH2complexes except when the substituent X is a more electropositive group. EOM‐CCSD spin‐spin coupling constants1pJ(O−P) across pnicogen bonds in H2CO:PXH2and HCO2H : PXH2complexes increase as the O−P distance decreases, and exhibit a second order dependence on that distance. There is no correlation between2hJ(O−P) and the O−P distance across the hydrogen bond in the HCO2H : PXH2complexes.2hJ(O−P) coupling constants for complexes with X=CH3and H have much greater absolute values than anticipated from their O−P distances.
Improvement of the input performance of a three‐phase‐single‐phase matrix converter based on space vector modulation
Authors: Xu Yuxiang , Wang Peiliang , Cai Zhiduan , Jiang Yongfeng
Published: February 2020

A 6‐switch three‐phase to single‐phase matrix converter (3‐1MC) with independent neutral line is directly coupled to the input side through bidirectional switches, and the output ripple power produces low‐frequency harmonics in the input side that are difficult to filter out. In this paper, the expressions of the frequencies and contents of the low‐frequency harmonics are derived based on the principle of input‐output instantaneous power conservation. Then, a 3‐1MC topology with decoupling unit is studied and the working principle and process of improving the input performance are analyzed. Second, based on the relationship between the output side and the decoupling side modulation function, the influence of the introduction of the decoupling unit on the maximum voltage transfer ratio of 3‐1MC is studied. The relationship between the voltage transfer ratio and parameters such as decoupling unit and output frequency is derived in detail. It is proved that maximum voltage transfer ratio of the topology is a nonlinear function related to system parameters. Then, the operating principle and modulation method of 3‐1MC are discussed. A double‐side current closed‐loop control strategy based on space vector modulation under power decoupling conditions is proposed. Finally, an experimental platform is built to verify that the 3‐1MC with decoupling unit can suppress the low‐frequency harmonics in the input current at different output frequencies and effectively improve the performance of the input side. The results show that the 3‐1MC with the decoupling unit is beneficial for use in single‐phase applications.
Experimental observation of intermittent route to chaos in magnetized filamentary discharge plasma due to the cylindrical plasma bubble
Authors: Megalingam Mariammal , Sangem Anurag , Sarma Bornali
Published: February 2020

We delineate an experimental observation of the effect of the magnetic field along with mesh grid biasing in the presence of a cylindrical plasma bubble in a filamentary discharge magnetised plasma system. The cylindrical mesh grid of 80% optical transparency has been negatively biased and introduced in the plasma for creating a plasma bubble. Plasma floating potential fluctuations have been taken outside (LP1) and inside (LP2) of the plasma bubble. It has been noticed that as the external magnetic field is increased the oscillation pattern shows intermittent route to chaos as the system evolved from regular type of relaxation oscillations (of larger amplitude) to an irregular type of oscillations (of smaller amplitude) We have used recurrence quantification analysis (RQA) to the observed intermittency to chaos in the plasma. The main measures of RQA are laminarity (LAM) and determinism (DET). The laminarity measure can be associated with the average time between the chaotic burst in the intermittency. It has also been observed that the DET depends on the control parameter and decreases exponentially, features like a dip in skewness and a hump in the kurtosis with the variation of control parameter have been noticed, which are the strong evidence of intermittent behaviour of the system. Further, a numerical model has been developed to the observed experimental analysis of the intermittent route to chaos.
Ecological drivers of African swine fever virus persistence in wild boar populations: Insight for control
Authors: Pepin Kim M. , Golnar Andrew J. , Abdo Zaid , Podgórski Tomasz
Published: February 2020

Environmental sources of infection can play a primary role in shaping epidemiological dynamics; however, the relative impact of environmental transmission on host‐pathogen systems is rarely estimated. We developed and fit a spatially explicit model of African swine fever virus (ASFV) in wild boar to estimate what proportion of carcass‐based transmission is contributing to the low‐level persistence of ASFV in Eastern European wild boar. Our model was developed based on ecological insight and data from field studies of ASFV and wild boar in Eastern Poland. We predicted that carcass‐based transmission would play a substantial role in persistence, especially in low‐density host populations where contact rates are low. By fitting the model to outbreak data using approximate Bayesian computation, we inferred that between 53% and 66% of transmission events were carcass‐based that is, transmitted through contact of a live host with a contaminated carcass. Model fitting and sensitivity analyses showed that the frequency of carcass‐based transmission increased with decreasing host density, suggesting that management policies should emphasize the removal of carcasses and consider how reductions in host densities may drive carcass‐based transmission. Sensitivity analyses also demonstrated that carcass‐based transmission is necessary for the autonomous persistence of ASFV under realistic parameters. Autonomous persistence through direct transmission alone required high host densities; otherwise re‐introduction of virus periodically was required for persistence when direct transmission probabilities were moderately high. We quantify the relative role of different persistence mechanisms for a low‐prevalence disease using readily collected ecological data and viral surveillance data. Understanding how the frequency of different transmission mechanisms vary across host densities can help identify optimal management strategies across changing ecological conditions.
Redox‐Switchable Transfer Hydrogenations with P‐Chiral Dendritic Ferrocenyl Phosphine Complexes
Authors: Popp John , Caminade Anne‐Marie , Hey‐Hawkins Evamarie
Published: February 2020

Attaining absolute control over a catalytic process and, therewith, exploiting its full potential pleases scientists in their ambitious and ongoing endeavor to perform catalysis like Nature does. In this regard, redox‐switchable catalysis certainly holds great potential, constantly gaining importance in modern catalysis research. Herein, we report the application of P‐stereogenic dendritic ferrocenyl phosphines in the ruthenium‐catalyzed redox‐switchable transfer hydrogenation of a ketone yielding an enantioenriched alcohol. By adding a chemical oxidant or reductant, the catalytic activity of the complexes was reversibly switched off and back on again over the course of the hydrogen transfer reaction. This has been rationalized mainly in terms of a distinct electronic communication between the redox‐active group and the catalytic center. The highly functionalized dendritic catalysts presented here might impact the way prospective homogeneous catalysts will be designed.
Influence of process parameters on the energy requirements and dried sliced tomato quality
Authors: Nwakuba Nnaemeka R. , Chukwuezie Osita C. , Asonye Gladys U. , Asoegwu Sabbas N.
Published: February 2020

This study presents the effects of process parameters on the energy demand for drying and quality indices of dried tomato slices. The experiment was designed and analyzed with the Box‐Behnken method of Design Expert and conducted for drying 1800 g batch of a local variety of tomatoes with a solar‐electric dryer. The study examined the impact of varying process parameters: air temperature (50°C, 60°C, and 70°C), sample thicknesses (10, 15, and 20 mm), and air velocities (1.0, 1.5, and 2.0 ms−1) on the total and specific energy requirements, drying time, lycopene content, ascorbic acid, nonenzymatic browning index, brightness, and ratio of redness to yellowness of dried tomato samples, with emphasis on process optimization and drying time. The prediction of the optimal process condition is obtained using the desirability index technique. The results obtained show that the total and specific energy requirements for a batch of tomato varied from 7.82 to 125.48 kJ h and 6.70 to 179.83 kJ h g−1. The results of the analysis of variance (ANOVA) indicate that all the studied process parameters were significant with P > .05; with the maximum (40.21%) and minimum (19.82%) percent energy contribution by air temperature and air velocity, respectively. The energy of activation varies between 20.26 and 39.35 kJ mol−1. At the optimum process conditions of 57.28°C, 14.08 mm, and 1.3 ms−1, the specific energy requirements, lycopene content, ascorbic acid content, nonenzymatic browning index, brightness, redness to yellowness ratio, and drying duration are obtained as 103.313 ± 2.35 kW h kg−1, 58.7 ± 2.19 mg/100 mg dry matter, 2.9 ± 0.26 mg/g, 0.51 ± 0.033 absorbance unit, 60.074 ± 1.44, 0.77 ± 0.021, and 61.88 ± 8.93 minutes, respectively. The results of the study are of immense benefit to the food drying industry, as it provides food industries with improved drying parameters for enhancing dried tomato quality, as well as increasing dryer energy efficiency and cost‐effectiveness. Sugestions on prospects for further studies were given.
Investigation on jet grouting support strategy for controlling time‐dependent deformation in the roadway
Authors: Sun Yuantian , Li Guichen , Zhang Junfei
Published: February 2020

The efficiency of coal mining is seriously affected by roadway stability, as large time‐dependent deformation of roadway frequently occurs and needs to be maintained several times during its service life. Such rheological deformation was common in soft coal mass at Huaibei coalfield in China. To address this issue, in this study, the time‐dependent deformation of the soft coal roadway was analyzed and a new Jet Grouting (JG) technique was presented for controlling deformation. The time‐dependent deformation of the soft coal roadway was numerically simulated and validated. Based on the field test results and the verified model, a JG support model was established to examine its effect on roadway deformation. The JG support system can reduce the horizontal and vertical displacement of the roadway effectively and constrain the time‐dependent deformation of coal mass. The deformation rate and stabilization time of roadway decreased significantly by comparison with conventional support. This work presented a promising JG support scheme for controlling the time‐dependent deformation in the roadway in deep underground mine, which can greatly promote the JG design and application.
Safety assessment of glutaminase from Aspergillus niger
Authors: Vo Trung Duc , Sulaiman Christina , Tafazoli Shahrzad , Lynch Barry , Roberts Ashley , Chikamatsu Go
Published: February 2020

Glutaminase (glutamine aminohydrolase EC 3.5.1.2) is used in the production of food ingredients rich in l‐glutamic acid that are added to finished foods for the purpose of enhancing or improving the savory flavor profile of food. The glutaminase enzyme preparation evaluated in these studies, designated as Sumizyme GT hereafter, is obtained by fermentation of Aspergillus niger strain GT147. The safety of Sumizyme GT was evaluated in a series of standard toxicological studies, including a 90‐day oral toxicity study in rats, an in vitro bacterial reverse mutation assay, an in vitro mammalian chromosome aberration test, and an in vivo alkaline Comet assay. Sumizyme GT was not mutagenic or genotoxic, and administration of the enzyme by gavage at doses up to 2,570 mg total organic solids (TOS)/kg body weight (bw) per day for 90 days was without any systemic toxicity. The no‐observed‐adverse‐effect level was concluded to be 2,570 mg TOS/kg bw per day, the highest dose tested. Considering that A. niger has an established history of safe use in the food industry and its safety in the production of food ingredients and food enzymes is well documented, the results of these studies provide further support of the safety of glutaminase from A. niger when used in food production.
Optimization in continuous phase‐transition extraction of crude flavonoids from finger citron fruit and evaluation on their antiaging activities
Authors: Chen Haiqiang , Wang Jing , Liu Xiaojuan , Zhou Aimei , Xiao Jie , Huang Kaixin , Chen Hanmin , Cao Yong
Published: February 2020

The development of antiaging functional products is a hot topic in the field of functional foods. However, the efficient extraction of functional ingredients is the limiting step for the functional food industry. Continuous phase‐transition extraction (CPE) is a new extraction technique that combines the advantages of Soxhlet extraction and supercritical extraction, which may have a distinct advantage over traditional methods in the extraction of flavonoids. In our study, the Box–Behnken design combined with response surface methodology was used to optimize CPE of crude flavonoids from finger citron fruit. The antiaging activities of finger citron crude flavonoids (FCCF) were evaluated by Caenorhabditis elegans (C. elegans) model. The optimal extraction conditions for CPE were as follows: ethanol concentration 85%, temperature 90°C, time 120 min, and pressure 0.2 MPa. Compared with the heat reflux extraction, the extraction rate and content of FCCF extracted by CPE increased by 24.28% and 33.22% (p < .05), respectively. FCCF extended the lifespan of C. elegans by 14.94% without causing adverse effects on their reproduction and locomotion ability. A further analysis suggested that FCCF prolonged the lifespan of nematodes under normal and oxidative stress by increasing the activity of major enzymes in endogenous antioxidant defense system and reducing the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA). The results confirmed the effectiveness of CPE in extracting crude flavonoids from finger citron fruit, and the extracted FCCF exhibited strong antiaging activities.
Determination of the creep behavior of potato tubers during storage period by means of uniaxial and triaxial creep tests
Authors: Shahgholi Gholamhossein , Latifi Meysam , Imani Behrooz , Farrokhi Niusha
Published: February 2020

The analysis of static forces is essential in the storage of agricultural products because these forces are applied in fruits, vegetables, or grains that can lead to their permanent deformation. This mechanical damage increases the product waste. Given that the potato tuber is surrounded by other tubers in the storage, then every tuber is pressurized from all sides or so‐called triaxial stress. To measure the deformation of the specimens, a device was developed to conduct uniaxial and triaxial creep tests on the viscoelastic agricultural products (e.g., potatoes). Accordingly, the creep experiments were performed on potato samples for 5, 30, 60, 120, 240, 360, 420, and 480 min under the constant load of 72.5 N at 3 and 11 replications via uniaxial and triaxial tests, respectively. The results showed that in the creep test, the loading time was significant on the deformation of the specimens at the 0.05 level of probability. Triaxial test showed that the tuber deformation and strain of top layer were more than the middle and bottom layers. The results showed that the deformation of tubers under uniaxial test was more than triaxial one.
A new Carboniferous–Permian intra‐oceanic subduction system in the North Tianshan (NW China): Implications for multiple accretionary tectonics of the southern Altaids
Authors: Bai Xueyin , Chen Yichao , Song Dongfang , Xiao Wenjiao , Windley Brian F. , Ao Songjian , Li Liang , Xiang Dunfeng
Published: February 2020

The North Tianshan in NW China is a key to understanding the accretionary history of the southern Altaids. However, the tectonic setting of the North Tianshan in the Carboniferous‐Permian is debatable, and its amalgamation history is ambiguous. We report new data on the field relations, geochronology and geochemistry of Carboniferous–Jurassic volcanic rocks and sedimentary rocks from the Shichang area in order to constrain the late Palaeozoic–Early Mesozoic tectonic evolution of the North Tianshan. New LA‐ICP‐MS zircon U–Pb dates demonstrate that the Carboniferous–Permian stratigraphy is a tectonic imbrication of Carboniferous–Permian rocks and Carboniferous volcanic rocks were emplaced in Permian volcano‐sedimentary rocks. The 311 ± 2 Ma volcanic rocks are calc‐alkaline, enriched in Light Rare Earth Elements and large‐ion lithophile elements, depleted in high‐field‐strength elements, and have low initial87Sr/86Sr ratios with positiveεNd(t)(+0.3 to +8.6)values. The geochemical‐isotopic data suggest the volcanic rocks were generated in an intra‐oceanic island arc. The turbidite samples 18SC02 (~267 Ma to ~349 Ma) and 18SC09 (~299 Ma to ~369 Ma) have a relatively narrow age range with no Devonian or Precambrian peaks. Our detrital zircon data suggest the presence of a so far unrecognized intra‐oceanic arc, which was isolated from the main Yili‐Central Tianshan and Mosuowan arcs in the Shichang area of the North Tianshan during the Late Carboniferous to Permian. The compiled detrital zircon data from Carboniferous to Jurassic indicates that the North Tianshan intra‐oceanic arc was probably amalgamated with the Mosuowan arc by the Early Triassic, and then accreted to the Yili‐Central Tianshan arc by the Middle‐Late Triassic, as revealed by the changes of zircon provenance of Carboniferous, Permian, Triassic and Jurassic sedimentary rocks. All integrated data suggest that the southern Altaids most likely formed by processes of multiple subduction–accretion and convergence similar to that in the ongoing southwest Pacific.
DNA methylation: A mechanism for sustained alteration of KIR4.1 expression following central nervous system insult
Authors: Boni Jessica L. , Kahanovitch Uri , Nwaobi Sinifunanya E. , Floyd Candace L. , Olsen Michelle L.
Published: February 2020

Kir4.1, a glial‐specific inwardly rectifying potassium channel, is implicated in astrocytic maintenance of K+ homeostasis. Underscoring the role of Kir4.1 in central nervous system (CNS) functioning, genetic mutations in KCNJ10, the gene which encodes Kir4.1, causes seizures, ataxia and developmental disability in humans. Kir4.1 protein and mRNA loss are consistently observed in CNS injury and neurological diseases linked to hyperexcitability and neuronal dysfunction, leading to the notion that Kir4.1 represents an attractive therapeutic target. Despite this, little is understood regarding the mechanisms that underpin this downregulation. Previous work by our lab revealed that DNA hypomethylation of the Kcnj10 gene functions to regulate mRNA levels during astrocyte maturation whereas hypermethylation in vitro led to decreased promoter activity. In the present study, we utilized two vastly different injury models with known acute and chronic loss of Kir4.1 protein and mRNA to evaluate the methylation status of Kcnj10 as a candidate molecular mechanism for reduced transcription and subsequent protein loss. Examining whole hippocampal tissue and isolated astrocytes, in a lithium‐pilocarpine model of epilepsy, we consistently identified hypermethylation of CpG island two, which resides in the large intronic region spanning the Kcnj10 gene. Strikingly similar results were observed using the second injury paradigm, a fifth cervical (C5) vertebral hemi‐contusion model of spinal cord injury. Our previous work indicates the same gene region is significantly hypomethylated when transcription increases during astrocyte maturation. Our results suggest that DNA methylation can bidirectionally modulate Kcnj10 transcription and may represent a targetable molecular mechanism for the restoring astroglial Kir4.1 expression following CNS insult.
Precision (Mis)Education
Authors: Matthews Lucas J.
Published: February 2020

In August of 2018, the results of the largest genomic investigation in human history were published. Scanning the DNA of over one million participants, a genome‐wide association study was conducted to identify genetic variants associated with the number of years of education a person has completed. This measure, called “educational attainment,” is often treated as a proxy for intelligence and cognitive ability. The study raises a host of hard philosophical questions about study design and strength of evidence. It also sets the basis for something far more controversial. Using a new genomic method that generates “polygenic scores,” researchers are now able to use the results of the study to predict a person's educational potential from a blood or saliva sample. Going a step further, some researchers have begun to promote “precision education,” which would tailor students’ school plans to their genetic profiles. The idea of precision education provokes concerns about stigma and self‐fulfilling prophecies.
Pediatric Drug Labeling and Imperfect Information
Authors: Wilfond Benjamin S.
Published: February 2020

I first became aware of bioethics in the spring of 1980. I had spent a thirty‐six‐hour shift shadowing a medical resident, and I was struck that many of the resident's decisions had ethical dimensions. The next day, I came across the Hastings Center Report, and I realized I wanted to explore ethical issues I found implicit in clinical care, even though I still wanted to become a pediatrician. In September 2019, when I attended my first meeting of the U.S. Food and Drug Administration's Pediatric Advisory Committee, as a pediatric pulmonologist, I had the same sense of awe and curiosity that I had forty years ago. What had appeared initially as somewhat technical decisions about the regulation of drug labeling was suffused with ethical questions. The committee was asked to discuss possible changes to the labeling of two previously approved drugs.