bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeted Disruption of Bone Marrow Stromal Cell-Derived Gremlin1 Limits Multiple Myeloma Disease Progression In Vivo
Authors: Clark Kimberley C. , Hewett Duncan R. , Panagopoulos Vasilios , Plakhova Natalya , Opperman Khatora S. , Bradey Alanah L. , Mrozik Krzysztof M. , Vandyke Kate , Mukherjee Siddhartha , Davies Gareth C.G. , Worthley Daniel L. , Zannettino Andrew C.W.
Published: August 2020

In most instances, multiple myeloma (MM) plasma cells (PCs) are reliant on factors made by cells of the bone marrow (BM) stroma for their survival and growth. To date, the nature and cellular composition of the BM tumor microenvironment and the critical factors which drive tumor progression remain imprecisely defined. Our studies show that Gremlin1 (Grem1), a highly conserved protein, which is abundantly secreted by a subset of BM mesenchymal stromal cells, plays a critical role in MM disease development. Analysis of human and mouse BM stromal samples by quantitative PCR showed that GREM1/Grem1 expression was significantly higher in the MM tumor-bearing cohorts compared to healthy controls (p < 0.05, Mann–Whitney test). Additionally, BM-stromal cells cultured with 5TGM1 MM PC line expressed significantly higher levels of Grem1, compared to stromal cells alone (p < 0.01, t-test), suggesting that MM PCs promote increased Grem1 expression in stromal cells. Furthermore, the proliferation of 5TGM1 MM PCs was found to be significantly increased when co-cultured with Grem1-overexpressing stromal cells (p < 0.01, t-test). To examine the role of Grem1 in MM disease in vivo, we utilized the 5TGM1/KaLwRij mouse model of MM. Our studies showed that, compared to immunoglobulin G (IgG) control antibody-treated mice, mice treated with an anti-Grem1 neutralizing antibody had a decrease in MM tumor burden of up to 81.2% (p < 0.05, two-way ANOVA). The studies presented here demonstrate, for the first time, a novel positive feedback loop between MM PCs and BM stroma, and that inhibiting this vicious cycle with a neutralizing antibody can dramatically reduce tumor burden in a preclinical mouse model of MM.
N-Iodosuccinimide as a Precatalyst for Direct Cross-Coupling of Alcohols with C-Nucleophiles under Solvent-Free Reaction Conditions
Authors: Ajvazi Njomza , Stavber Stojan
Published: August 2020

C–C bond formation is one of the most important implements in synthetic organic chemistry. In pursuit of effective synthetic routes functioning under greener pathways to achieve direct C–C bond formation, we report N-iodosuccinimide (NIS) as the most effective precatalyst among the N-halosuccinimides (NXSs) for the direct cross-coupling of benzyl alcohols with C-nucleophiles under solvent-free reaction conditions (SFRC). The protocol is metal-free, and air- and water-tolerant, providing a large-scale synthesis with almost quantitative yields.
Estimating the Product Inhibition Constant from Enzyme Kinetic Equations Using the Direct Linear Plot Method in One-Stage Treatment
Authors: Valencia Pedro L. , Sepúlveda Bastián , Gajardo Diego , Astudillo-Castro Carolina
Published: August 2020

A direct linear plot was applied to estimate kinetic constants using the product’s competitive inhibition equation. The challenge consisted of estimating three kinetic constants, Vmax, Km, and Kp, using two independent variables, substrates, and product concentrations, in just one stage of mathematical treatment. The method consisted of combining three initial reaction rate data and avoiding the use of the same three product concentrations (otherwise, this would result in a mathematical indetermination). The direct linear plot method was highly superior to the least-squares method in terms of accuracy and robustness, even under the addition of error. The direct linear plot method is a reliable and robust method that can be applied to estimate Kp in inhibition studies in pharmaceutical and biotechnological areas.
Visible-Light Driven Photocatalytic Degradation of Pirimicarb by Pt-Doped AgInS2 Nanoparticles
Authors: Tsai Hweiyan , Shaya Janah , Tesana Siriluck , Golovko Vladimir B. , Wang Syuan-Yun , Liao Yi-Yen , Lu Chung-Shin , Chen Chiing-Chang
Published: August 2020

This study describes the synthesis and characterization of Pt-doped AgInS2 nanoparticles and reports their prospective application as visible-light catalysts for photodegradation of frequently used pirimicarb insecticides, which pose serious health and environmental concerns. The nanomaterials were characterized by XRD, SEM, TEM, XPS, photoluminescence (PL), and UV–vis diffuse reflectance spectra (DRS). The presented photocatalytic method for water treatment from pirimicarb has the advantages of using visible light source without any costly additive such as H2O2 needed in other employed methods. The Pt-doped AgInS2 exhibited higher photocatalytic activities for pirimicarb degradation than undoped AgInS2. The 1.0 wt% Pt/AgInS2 photocatalyst exhibited the highest photodegradation rate, showing enhancement of 56% in comparison to the pure AgInS2 photocatalyst. The photodegradation rate was found to increase with increasing the catalyst dosage until reaching the optimal dosage of 1.0 g L−1. The pirimicarb degradation was significantly more efficient under acidic conditions, and the rates drastically dropped upon increasing the pH. The photocatalytic mechanism of Pt/AgInS2 composites and the main active species involved in the process were investigated. The mechanism of pirimicarb degradation was proposed via two different pathways, N-dealkylation and decarbamoylation. Lastly, the photocatalysts demonstrated remarkable stability and were reusable in three successive catalytic tests without compromising catalytic activities. The Pt/AgInS2 photocatalyst also exhibited efficiency and feasibility in pirimicarb removal from environmental lake and river water samples.
Recent Advances in the Catalyst Design and Mass Transport Control for the Electrochemical Reduction of Carbon Dioxide to Formate
Authors: Alfath Muhammad , Lee Chan Woo
Published: August 2020

Closing the carbon cycle by the electrochemical reduction of CO2 to formic acid and other high-value chemicals is a promising strategy to mitigate rapid climate change. The main barriers to commercializing a CO2 reduction reaction (CO2RR) system for formate production are the chemical inertness, low aqueous solubility, and slow mass transport characteristics of CO2, along with the low selectivity and high overpotential observed in formate production via CO2 reduction. To address those problems, we first explain the possible reaction mechanisms of CO2RRs to formate, and then we present and discuss several strategies to overcome the barriers to commercialization. The electronic structure of the catalyst can be tuned to favor a specific intermediate by adjusting the catalyst composition and tailoring the facets, edges, and corners of the catalyst to better expose the active sites, which has primarily led to increased catalytic activity and selectivity. Controlling the local pH, employing a high-pressure reactor, and using systems with three-phase boundaries can tune the mass transport properties of reactants at the catalyst surface. The reported electrocatalytic performances are summarized afterward to provide insight into which strategies have critical effects on the production of formate.
Vanadium(V) Complex-Catalyzed One-Pot Synthesis of Phenanthridines via a Pictet-Spengler-Dehydrogenative Aromatization Sequence
Authors: Sako Makoto , Losa Romain , Takiishi Tomohiro , Vo-Thanh Giang , Takizawa Shinobu , Sasai Hiroaki
Published: August 2020

Phenanthridine and its derivatives are important structural motifs that exist in natural products, biologically active compounds, and functional materials. Here, we report a mild, one-pot synthesis of 6-arylphenanthridine derivatives by a sequential cascade Pictet-Spengler-dehydrogenative aromatization reaction mediated by oxovanadium(V) complexes under aerobic conditions. The reaction of 2-(3,5-dimethoxyphenyl)aniline with a range of commercially available aryl aldehydes provided the desired phenanthridine derivatives in up to 96% yield. The ability of vanadium(V) complexes to function as efficient redox and Lewis acid catalysts enables the sequential reaction to occur under mild conditions.
The Influence of Residual Sodium on the Catalytic Oxidation of Propane and Toluene over Co3O4 Catalysts
Authors: Chai Guangtao , Zhang Weidong , Guo Yanglong , Valverde Jose Luis , Giroir-Fendler Anne
Published: August 2020

A series of Co3O4 catalysts with different contents of residual sodium were prepared using a precipitation method with sodium carbonate as a precipitant and tested for the catalytic oxidation of 1000 ppm propane and toluene at a weight hourly space velocity of 40,000 mL g−1 h−1, respectively. Several techniques were used to characterize the physicochemical properties of the catalysts. Results showed that residual sodium could be partially inserted into the Co3O4 spinel lattice, inducing distortions and helping to increase the specific surface area of the Co3O4 catalysts. Meanwhile, it could negatively affect the reducibility and the oxygen mobility of the catalysts. Moreover, residual sodium had a significant influence on the catalytic activity of propane and toluene oxidation over the synthesized Co3O4 catalysts. The catalyst derived from the precursor washed three times presented the best activity for the catalytic oxidation of propane. The origin was traced to its better reducibility and higher oxygen mobility, which were responsible for the formation of active oxygen species. On the other hand, the catalyst obtained from the precursor washed two times exhibited better performance in toluene oxidation, benefitting from its more defective structure and larger specific surface area. Furthermore, the most active catalysts maintained constant performance in cycling and long-term stability tests of propane and toluene oxidation, being potentially applicable for practical applications.
Probing the Surface Acidity of Supported Aluminum Bromide Catalysts
Authors: Abedin Md Ashraful , Kanitkar Swarom , Kumar Nitin , Wang Zi , Ding Kunlun , Hutchings Graham , Spivey James J.
Published: August 2020

Solid acid catalysis is an important class of reactions. The principal advantages of solid acid catalysts as compared to their corresponding fluid acids include minimal waste and ease of product separation. One type of these catalysts is based on aluminum bromide (Al2Br6), which is a stronger Lewis acid than Al2Cl6. In this report, Al2Br6 is grafted on commercial mesoporous silica (CMS), SBA-15 and silica gel to create a solid catalyst similar to the silica-supported Al2Cl6 superacid. These supported Al2Br6 catalysts were characterized by NH3-Temperature Programmed Desorption (TPD), pyridine Diffuse Reflectance for Infrared Fourier Transform Spectroscopy (DRIFTS) and Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR). Formation of acid sites was confirmed and quantified with NH3-TPD. Both Lewis and Brønsted sites were observed with DRIFTS using pyridine as a probe molecule. In addition, thermal stability of acid sites was also studied using DRIFTS. 27Al MAS NMR analysis showed tetrahedral, pentahedral and octahedral co-ordination of Al, confirming that Al2Br6 reacted with –OH groups on silica surface. Performance of these catalysts was evaluated using acid-catalyzed 1-butene isomerization. Conversion above 80% was observed at 200 °C, corresponding to thermodynamic equilibrium.
Cyclopamine and Rapamycin Synergistically Inhibit mTOR Signalling in Mouse Hepatocytes, Revealing an Interaction of Hedgehog and mTor Signalling in the Liver
Authors: Spormann Luise , Rennert Christiane , Kolbe Erik , Ott Fritzi , Lossius Carolin , Lehmann Robert , Gebhardt Rolf , Berg Thomas , Matz-Soja Madlen
Published: August 2020

In the liver, energy homeostasis is mainly regulated by mechanistic target of rapamycin (mTOR) signalling, which influences relevant metabolic pathways, including lipid metabolism. However, the Hedgehog (Hh) pathway is one of the newly identified drivers of hepatic lipid metabolism. Although the link between mTOR and Hh signalling was previously demonstrated in cancer development and progression, knowledge of their molecular crosstalk in healthy liver is lacking. To close this information gap, we used a transgenic mouse model, which allows hepatocyte-specific deletion of the Hh pathway, and in vitro studies to reveal interactions between Hh and mTOR signalling. The study was conducted in male and female mice to investigate sexual differences in the crosstalk of these signalling pathways. Our results reveal that the conditional Hh knockout reduces mitochondrial adenosine triphosphate (ATP) production in primary hepatocytes from female mice and inhibits autophagy in hepatocytes from both sexes. Furthermore, in vitro studies show a synergistic effect of cyclopamine and rapamycin on the inhibition of mTor signalling and oxidative respiration in primary hepatocytes from male and female C57BL/6N mice. Overall, our results demonstrate that the impairment of Hh signalling influences mTOR signalling and therefore represses oxidative phosphorylation and autophagy.
Repeated Application of Autologous Bone Marrow-Derived Lineage-Negative Stem/Progenitor Cells—Focus on Immunological Pathways in Patients with ALS
Authors: Baumert Bartłomiej , Sobuś Anna , Gołąb-Janowska Monika , Paczkowska Edyta , Łuczkowska Karolina , Rogińska Dorota , Zawiślak Alicja , Milczarek Sławomir , Osękowska Bogumiła , Pawlukowska Wioletta , Meller Agnieszka , Machowska-Sempruch Karolina , Wełnicka Agnieszka , Safranow Krzysztof , Nowacki Przemysław , Machaliński Bogusław
Published: August 2020

Therapeutic interventions in amyotrophic lateral sclerosis (ALS) are still far from satisfying. Immune modulating procedures raise hopes for slowing the disease progression. Stem cell therapies are believed to possess the ability to regulate innate and adaptive immune response and inflammation processes. Hence, three intrathecal administrations of autologous bone marrow-derived lineage-negative (Lin–) cells were performed every six weeks in 40 sporadic ALS patients. The concentrations of inflammatory-related proteins and expression profiles of selected miRNA in the cerebrospinal fluid (CSF) and plasma at different timepoints post-transplantation were quantified by multiplex Luminex and qRT-PCR. The global gene expression in nucleated blood cells was assessed using the gene microarray technique. According to the ALS Functional Rating Scale (FRSr), the study population was divided into responders (group I, n = 17) and non-responders (group II, n = 23). A thorough analysis of the pro-inflammatory expression profiles, regulated miRNA pathways, and global gene expression profiles at the RNA level revealed the local and systemic effects of Lin– cell therapy on the immune system of patients with ALS. The autologous application of Lin– cells in CSF modulates immune processes and might prevent the progression of neurodegeneration. However, further in-depth studies are necessary to confirm the findings, and prolonged intervention is needed to maintain therapeutic effects.
Necroptosis in Immuno-Oncology and Cancer Immunotherapy
Authors: Sprooten Jenny , De Wijngaert Pieter , Vanmeerbeek Isaure , Martin Shaun , Vangheluwe Peter , Schlenner Susan , Krysko Dmitri V. , Parys Jan B. , Bultynck Geert , Vandenabeele Peter , Garg Abhishek D.
Published: August 2020

Immune-checkpoint blockers (ICBs) have revolutionized oncology and firmly established the subfield of immuno-oncology. Despite this renaissance, a subset of cancer patients remain unresponsive to ICBs due to widespread immuno-resistance. To “break” cancer cell-driven immuno-resistance, researchers have long floated the idea of therapeutically facilitating the immunogenicity of cancer cells by disrupting tumor-associated immuno-tolerance via conventional anticancer therapies. It is well appreciated that anticancer therapies causing immunogenic or inflammatory cell death are best positioned to productively activate anticancer immunity. A large proportion of studies have emphasized the importance of immunogenic apoptosis (i.e., immunogenic cell death or ICD); yet, it has also emerged that necroptosis, a programmed necrotic cell death pathway, can also be immunogenic. Emergence of a proficient immune profile for necroptosis has important implications for cancer because resistance to apoptosis is one of the major hallmarks of tumors. Putative immunogenic or inflammatory characteristics driven by necroptosis can be of great impact in immuno-oncology. However, as is typical for a highly complex and multi-factorial disease like cancer, a clear cause versus consensus relationship on the immunobiology of necroptosis in cancer cells has been tough to establish. In this review, we discuss the various aspects of necroptosis immunobiology with specific focus on immuno-oncology and cancer immunotherapy.
Cardiomyocyte Transplantation after Myocardial Infarction Alters the Immune Response in the Heart
Authors: Vasudevan Praveen , Wolfien Markus , Lemcke Heiko , Lang Cajetan Immanuel , Skorska Anna , Gaebel Ralf , Koczan Dirk , Lindner Tobias , Engelmann Robby , Vollmar Brigitte , Krause Bernd Joachim , Wolkenhauer Olaf , Lang Hermann , Steinhoff Gustav , David Robert
Published: August 2020

We investigated the influence of syngeneic cardiomyocyte transplantation after myocardial infarction (MI) on the immune response and cardiac function. Methods and Results: We show for the first time that the immune response is altered as a result of syngeneic neonatal cardiomyocyte transplantation after MI leading to improved cardiac pump function as observed by magnetic resonance imaging in C57BL/6J mice. Interestingly, there was no improvement in the capillary density as well as infarct area as observed by CD31 and Sirius Red staining, respectively. Flow cytometric analysis revealed a significantly different response of monocyte-derived macrophages and regulatory T cells after cell transplantation. Interestingly, the inhibition of monocyte infiltration accompanied by cardiomyocyte transplantation diminished the positive effect of cell transplantation alone. The number of CD68+ macrophages in the remote area of the heart observed after four weeks was also different between the groups. Transcriptome analysis showed several changes in the gene expression involving circadian regulation, mitochondrial metabolism and immune responses after cardiomyocyte transplantation. Conclusion: Our work shows that cardiomyocyte transplantation alters the immune response after myocardial infarction with the recruited monocytes playing a role in the beneficial effect of cell transplantation. It also paves the way for further optimization of the efficacy of cardiomyocyte transplantation and their successful translation in the clinic.
Overexpression of Extradomain-B Fibronectin is Associated with Invasion of Breast Cancer Cells
Authors: Vaidya Amita , Wang Helen , Qian Victoria , Gilmore Hannah , Lu Zheng-Rong
Published: August 2020

Breast tumor heterogeneity is a major impediment to oncotherapy. Cancer cells undergo rapid clonal evolution, thereby acquiring significant growth and invasive advantages. The absence of specific markers of these high-risk populations precludes efficient therapeutic and diagnostic management of the disease. Given the critical function of tumor microenvironment in the oncogenic circuitry, we sought to determine the expression profile of the extracellular matrix oncoprotein, extradomain-B fibronectin (EDB-FN) in invasive breast cancer. Analyses of TCGA/GTEx databases and immunostaining of clinical samples found a significant overexpression of EDB-FN in breast tumors, which correlated with poor overall survival. Significant upregulation of EDB-FN was observed in invasive cell populations generated from relatively less invasive MCF7 and MDA-MB-468 cells by long-term TGF-β treatment and acquired chemoresistance. Treatment of the invasive cell populations with an AKT inhibitor (MK2206-HCl) reduced their invasive potential, with a concomitant decrease in their EDB-FN expression, partly through the phosphoAKT-SRp55 pathway. EDB-FN downregulation, with direct RNAi of EDB-FN or indirectly through RNAi of SRp55, also resulted in reduced motility of the invasive cell populations, validating the correlation between EDB-FN expression and invasion of breast cancer cells. These data establish EDB-FN as a promising molecular marker for non-invasive therapeutic surveillance of aggressive breast cancer.
Influence of the Emulsifier System on Breakup and Coalescence of Oil Droplets during Atomization of Oil-In-Water Emulsions
Authors: Taboada Martha , Leister Nico , Karbstein Heike , Gaukel Volker
Published: August 2020

Spray drying of whey protein-based emulsions is a common task in food engineering. Lipophilic, low molecular weight emulsifiers including lecithin, citrem, and mono- and diglycerides, are commonly added to the formulations, as they are expected to improve the processing and shelf life stability of the products. During the atomization step of spray drying, the emulsions are subjected to high stresses, which can lead to breakup and subsequent coalescence of the oil droplets. The extent of these phenomena is expected to be greatly influenced by the emulsifiers in the system. The focus of this study was therefore set on the changes in the oil droplet size of whey protein-based emulsions during atomization, as affected by the addition of low molecular weight emulsifiers. Atomization experiments were performed with emulsions stabilized either with whey protein isolate (WPI), or with combinations of WPI and lecithin, WPI and citrem, and WPI and mono- and diglycerides. The addition of lecithin promoted oil droplet breakup during atomization and improved droplet stabilization against coalescence. The addition of citrem and of mono- and diglycerides did not affect oil droplet breakup, but greatly promoted coalescence of the oil droplets. In order to elucidate the underlying mechanisms, measurements of interfacial tensions and coalescence times in single droplets experiments were performed and correlated to the atomization experiments. The results on oil droplet breakup were in good accordance with the observed differences in the interfacial tension measurements. The results on oil droplet coalescence correlated only to a limited extent with the results of coalescence times of single droplet experiments.
Using Discrete Multiphysics Modelling to Assess the Effect of Calcification on Hemodynamic and Mechanical Deformation of Aortic Valve
Authors: Mohammed Adamu Musa , Ariane Mostapha , Alexiadis Alessio
Published: August 2020

This study proposes a 3D particle-based (discrete) multiphysics approach for modelling calcification in the aortic valve. Different stages of calcification (from mild to severe) were simulated, and their effects on the cardiac output were assessed. The cardiac flow rate decreases with the level of calcification. In particular, there is a critical level of calcification below which the flow rate decreases dramatically. Mechanical stress on the membrane is also calculated. The results show that, as calcification progresses, spots of high mechanical stress appear. Firstly, they concentrate in the regions connecting two leaflets; when severe calcification is reached, then they extend to the area at the basis of the valve.
A Comprehensive Review of Bioactive Glass Coatings: State of the Art, Challenges and Future Perspectives
Authors: Sergi Rachele , Bellucci Devis , Cannillo Valeria
Published: August 2020

Bioactive glasses are promising biomaterials for bone and tissue repair and reconstruction, as they were shown to bond to both hard and soft tissues stimulating cells towards a path of regeneration and self-repair. Unfortunately, due to their relatively poor mechanical properties, such as brittleness, low bending strength and fracture toughness, their applications are limited to non-load-bearing implants. However, bioactive glasses can be successfully applied as coatings on the surface of metallic implants to combine the appropriate mechanical properties of metal alloys to bioactivity and biocompatibility of bioactive glasses. In this review, several available coating techniques to coat metal alloys using bioactive glasses are described, with a special focus on thermal spraying, which nowadays is the most used to deposit coatings on metallic implants.
Forecasting Economic Recession through Share Price in the Logistics Industry with Artificial Intelligence (AI)
Authors: Tang YM , Chau Ka-Yin , Li Wenqiang , Wan TW
Published: August 2020

Time series forecasting technology and related applications for stock price forecasting are gradually receiving attention. These approaches can be a great help in making decisions based on historical information to predict possible future situations. This research aims at establishing forecasting models with deep learning technology for share price prediction in the logistics industry. The historical share price data of five logistics companies in Hong Kong were collected and trained with various time series forecasting algorithms. Based on the Mean Absolute Percentage Error (MAPE) results, we adopted Long Short-Term Memory (LSTM) as the methodology to further predict share price. The proposed LSTM model was trained with different hyperparameters and validated by the Root Mean Square Error (RMSE). In this study, we found various optimal parameters for the proposed LSTM model for six different logistics stocks in Hong Kong, and the best RMSE result was 0.43%. Finally, we can forecast economic recessions through the prediction of the stocks, using the LSTM model.
Suppression of the s-Wave Order Parameter Near the Surface of the Infinite-Layer Electron-Doped Cuprate Superconductor Sr0.9La0.1CuO2
Authors: Khasanov Rustem , Shengelaya Alexander , Brütsch Roland , Keller Hugo
Published: August 2020

The temperature dependencies of the in-plane (λab) and out-of-plane (λc) components of the magnetic field penetration depth were investigated near the surface and in the bulk of the electron-doped superconductor Sr0.9La0.1CuO2 by means of magnetization measurements. The measured λab(T) and λc(T) were analyzed in terms of a two-gap model with mixed s+d-wave symmetry of the order parameter. λab(T) is well described by an almost pure anisotropic d-wave symmetry component (≃96%), mainly reflecting the surface properties of the sample. In contrast, λc(T) exhibits a mixed s+d-wave order parameter with a substantial s-wave component of more than 50%. The comparison of λab−2(T) measured near the surface with that determined in the bulk by means of the muon-spin rotation/relaxation technique demonstrates that the suppression of the s-wave component of the order parameter near the surface is associated with a reduction of the superfluid density by more than a factor of two.
A Combined Crystallographic and Computational Study on Dexketoprofen Trometamol Dihydrate Salt
Authors: Rossi Patrizia , Paoli Paola , Milazzo Stella , Chelazzi Laura , Giovannoni Maria Paola , Guerrini Gabriella , Ienco Andrea , Valleri Maurizio , Conti Luca
Published: August 2020

Dexketoprofen trometamol is the tromethamine salt of dexketoprofen [(2S)-2-(3-benzoylphenyl)propanoic acid-2-amino-2-(hydroxymethyl)propane-1,3-diol], a nonsteroidal anti-inflammatory drug (NSAID) used for the treatment of moderate- to strong-intensity acute pain. The crystal structure of the hitherto sole known hydrate phase of dexketoprofen trometamol (DK-T_2H2O), as determined by single-crystal X-ray diffraction, is presented. The water molecules are arranged in dimers included in isolated sites and sandwiched between piles of trometamol cations. The molecular and crystal structures of DK-T_2H2O are analyzed and compared to those of the parent anhydrous crystal form DK-T_A. In both the crystal structures, all the potential H-bond donors and acceptor of the dexketoprofen and trometamol ions are engaged, and both the species crystallize in the P21 space group. However, during the DK-T_A➔DK-T_2H2O hydration process, the unique symmetry axis is not conserved, i.e., the ions are arranged in a different way with respect to the screw axis, even if the two crystal structures maintain structural blocks of DK anions and T cations. Quantum mechanical solid-state calculations provide some hints for the possible intermediate structure during the crystalline–crystalline hydration/dehydration process.
Application of Artificial Neural Networks in Crystal Growth of Electronic and Opto-Electronic Materials
Authors: Dropka Natasha , Holena Martin
Published: August 2020

In this review, we summarize the results concerning the application of artificial neural networks (ANNs) in the crystal growth of electronic and opto-electronic materials. The main reason for using ANNs is to detect the patterns and relationships in non-linear static and dynamic data sets which are common in crystal growth processes, all in a real time. The fast forecasting is particularly important for the process control, since common numerical simulations are slow and in situ measurements of key process parameters are not feasible. This important machine learning approach thus makes it possible to determine optimized parameters for high-quality up-scaled crystals in real time.
The Electronic Properties of Extended Defects in SrTiO3—A Case Study of a Real Bicrystal Boundary
Authors: Rodenbücher Christian , Wrana Dominik , Gensch Thomas , Krok Franciszek , Korte Carsten , Szot Krzysztof
Published: August 2020

This study investigates the impact of extended defects such as dislocations on the electronic properties of SrTiO3 by using a 36.8° bicrystal as a model system. In order to evaluate the hypothesis that dislocations can serve as preferential reduction sites, which has been proposed in the literature on the basis of ab initio simulations, as well as on experiments employing local-conductivity atomic force microscopy (LC-AFM), detailed investigations of the bicrystal boundary are conducted. In addition to LC-AFM, fluorescence lifetime imaging microscopy (FLIM) is applied herein as a complementary method for mapping the local electronic properties on the microscale. Both techniques confirm that the electronic structure and electronic transport in dislocation-rich regions significantly differ from those of undistorted SrTiO3. Upon thermal reduction, a further confinement of conductivity to the bicrystal boundary region was found, indicating that extended defects can indeed be regarded as the origin of filament formation. This leads to the evolution of inhomogeneous properties of defective SrTiO3 on the nano- and microscales.
Halide Ion Embraces in Tris(2,2′-bipyridine)metal Complexes
Authors: Constable Edwin , Housecroft Catherine
Published: August 2020

An analysis of the [M(bpy)3]n+ (bpy = 2,2′-bipyridine) complexes with halide counterions in the Cambridge Structural Database reveals a common structural motif in two thirds of the compounds. This interaction involves the formation of 12 short C–H…X contacts between halide ions lying within sheets of the cations and H-3 and H-3′ of six [M(bpy)3]n+ complex cations. A second motif, also involving 12 short contacts, but with H-6 and H-5, is identified between halide ions lying between sheets of the [M(bpy)3]n+ cations.
An Environmental Data Collection for COVID-19 Pandemic Research
Authors: Liu Qian , Liu Wei , Sha Dexuan , Kumar Shubham , Chang Emily , Arora Vishakh , Lan Hai , Li Yun , Wang Zifu , Zhang Yadong , Zhang Zhiran , Harris Jackson T. , Chinala Srikar , Yang Chaowei
Published: August 2020

The COVID-19 viral disease surfaced at the end of 2019 and quickly spread across the globe. To rapidly respond to this pandemic and offer data support for various communities (e.g., decision-makers in health departments and governments, researchers in academia, public citizens), the National Science Foundation (NSF) spatiotemporal innovation center constructed a spatiotemporal platform with various task forces including international researchers and implementation strategies. Compared to similar platforms that only offer viral and health data, this platform views virus-related environmental data collection (EDC) an important component for the geospatial analysis of the pandemic. The EDC contains environmental factors either proven or with potential to influence the spread of COVID-19 and virulence or influence the impact of the pandemic on human health (e.g., temperature, humidity, precipitation, air quality index and pollutants, nighttime light (NTL)). In this platform/framework, environmental data are processed and organized across multiple spatiotemporal scales for a variety of applications (e.g., global mapping of daily temperature, humidity, precipitation, correlation of the pandemic to the mean values of climate and weather factors by city). This paper introduces the raw input data, construction and metadata of reprocessed data, and data storage, as well as the sharing and quality control methodologies of the COVID-19 related environmental data collection.
Defining Domestic Environmental Experience for Occupants’ Mental Health and Wellbeing
Authors: Chowdhury Sajal , Noguchi Masa , Doloi Hemanta
Published: August 2020

This study was stipulated by today’s limited living conditions of middle income households in Bangladesh who have economic constraints that contribute to hindering improvement of their existing domestic settings that may affect occupants’ mental health and wellbeing. The design of domestic living environments tend to influence occupants’ emotions, feelings and moods. Thus, domestic environmental experiences need to be examined and incorporated into architectural design decisions. To understand the notion of such experiences, this study reviewed literatures concerning the related domains extensively. This study found the significant impact of domestic environments on human perceptions. Each design of domestic settings affects occupants’ emotional responses positively or negatively. Through this study, the term domestic environmental experience was defined as users’ experiences of cognitive perceptions and physical responses to their domestic built environment. In addition, it led to proposing the composition of domestic environmental experiences that need to be correlated with architectural design solutions. Nonetheless, this study did not examine the correlation where the emerging notion of Environmental Experience Design (EXD) may serve as the mediator. Accordingly, this new horizon of EXD research needs to be explored further with the aim to improve domestic built environments in Bangladesh which were the original driver of this research.
Ultrasound Features of a Uterine Perivascular Epithelioid Cell Tumor (PEComa): Case Report and Literature Review
Authors: Giannella Luca , Delli Carpini Giovanni , Montik Nina , Verdecchia Valeria , Puccio Francesca , Di Giuseppe Jacopo , Tsiroglou Dimitrios , Goteri Gaia , Ciavattini Andrea
Published: August 2020

Background: Perivascular epithelioid cell tumors (PEComas) are rare mesenchymal tumors. One of the most frequent localizations of PEComas is the female genitourinary tract, and the uterus is the most involved site after the kidney. Correct preoperative diagnosis is rarely achieved due to the presence of nonspecific imaging features. We report a case of a uterine PEComa with particular reference to ultrasound’s role in characterizing this rare occurrence. Case presentation: a 45-year-old White woman came to our observation for cyclic abdominopelvic pain and chronic constipation. The pre-surgical ultrasound examination showed a heterogeneous tumor that was 4 cm in size, localized on the right anterolateral uterine wall. The mass had well-delimited borders and a central hypoechoic portion. The use of color Doppler showed a rich, irregular vasculature in the center with low impedance. The preoperative diagnostic hypothesis was of a smooth muscle tumor of uncertain malignant potential. After careful counseling, a surgical approach was decided upon, including a total laparoscopic hysterectomy with bilateral salpingectomy. The histological and phenotypical features were consistent with a uterine PEComa. At the last follow-up, two years after surgery, the patient is alive and well. Conclusions: Uterine PEComa is a rare occurrence that should be included in the differential diagnosis of uterine wall tumors. It can appear as a small uterine mass with heterogeneous echogenicity and a rich vascular pattern during an ultrasound evaluation. This diagnostic suspicion may assist in better surgical planning.
Active Carbon Modified by Rhenium Species as a Perspective Supercapacitor Electrode
Authors: Ciszewski Mateusz , Koszorek Andrzej , Hawełek Łukasz , Osadnik Małgorzata , Szleper Katarzyna , Drzazga Michał
Published: August 2020

We have reported the synthesis of a new kind of composite combining a rhenium precursor and active carbon. Similarly to other refractory metals, rhenium exhibits several oxidation states that makes it an ideal candidate for redox-type energy storage materials. A simple impregnation of pretreated active carbon with ammonium perrhenate allowed to produce an electrode material with an enhanced specific capacitance. There was not any observed detrimental effect of metal species on the cycle life of the electrode. A small increase in charge transfer resistance was counter-balanced by the improved impedance in the whole examined range.
Precise Positioning of Autonomous Vehicles Combining UWB Ranging Estimations with On-Board Sensors
Authors: San Martín Javier , Cortés Ainhoa , Zamora-Cadenas Leticia , Svensson Bo Joel
Published: August 2020

In this paper, we analyze the performance of a positioning system based on the fusion of Ultra-Wideband (UWB) ranging estimates together with odometry and inertial data from the vehicle. For carrying out this data fusion, an Extended Kalman Filter (EKF) has been used. Furthermore, a post-processing algorithm has been designed to remove the Non Line-Of-Sight (NLOS) UWB ranging estimates to further improve the accuracy of the proposed solution. This solution has been tested using both a simulated environment and a real environment. This research work is in the scope of the PRoPART European Project. The different real tests have been performed on the AstaZero proving ground using a Radio Control car (RC car) developed by RISE (Research Institutes of Sweden) as testing platform. Thus, a real time positioning solution has been achieved complying with the accuracy requirements for the PRoPART use case.
Research on Harmonic Torque Reduction Strategy for Integrated Electric Drive System in Pure Electric Vehicle
Authors: Hu Jianjun , Yang Ying , Jia Meixia , Guan Yongjie , Fu Chunyun , Liao Shuiping
Published: August 2020

In order to study the influence of harmonic torque on the performance of the integrated electric drive system (permanent magnet synchronous motor + reducer gear pair) in a pure electric vehicle (PEV), the electromechanical coupling dynamic model of a PEV was established by considering the dead-time effect and voltage drop effect of an inverter and the nonlinear characteristics of the transmission system. Based on the model, the dynamic characteristics of an integrated electric drive system (IEDS) are studied, and the interaction between the mechanical system and electrical system is analyzed. On this basis, a harmonic torque reduction strategy for an IEDS is proposed in this paper. The simulation results show that the proposed strategy can effectively reduce the harmonic torque of the motor and reduce the speed fluctuation and dynamic load of the system components, which can improve the stability of the IEDS and prolong the life of the mechanical components.
Effective PCB Decoupling Optimization by Combining an Iterative Genetic Algorithm and Machine Learning
Authors: Cecchetti Riccardo , de Paulis Francesco , Olivieri Carlo , Orlandi Antonio , Buecker Markus
Published: August 2020

An iterative optimization for decoupling capacitor placement on a power delivery network (PDN) is presented based on Genetic Algorithm (GA) and Artificial Neural Network (ANN). The ANN is first trained by an appropriate set of results obtained by a commercial simulator. Once the ANN is ready, it is used within an iterative GA process to place a minimum number of decoupling capacitors for minimizing the differences between the input impedance at one or more location, and the required target impedance. The combined GA–ANN process is shown to effectively provide results consistent with those obtained by a longer optimization based on commercial simulators. With the new approach the accuracy of the results remains at the same level, but the computational time is reduced by at least 30 times. Two test cases have been considered for validating the proposed approach, with the second one also being compared by experimental measurements.
Low-Noise Programmable Voltage Source
Authors: Achtenberg Krzysztof , Mikołajczyk Janusz , Ciofi Carmine , Scandurra Graziella , Bielecki Zbigniew
Published: August 2020

This paper presents the design and testing of a low-noise programmable voltage source. Such a piece of instrumentation is often required as part of the measurement setup needed to test electronic devices without introducing noise from the power supply (such as photodetectors, resistors or transistors). Although its construction is based on known configurations, here the discussion is focused on the characterization and the minimization of the output noise, especially at very low frequencies. The design relies on a digital-to-analog converter, proper lowpass filters, and a low-noise Junction Field-Effect Transistors (JFET) based voltage follower. Because of the very low level of output noise, in some cases we had to resort to cross-correlation in order to reduce the background noise of the amplifiers used for the characterization of the programmable source. Indeed, when two paralleled IF9030 JFETs are used in the voltage follower, the output noise can be as low as 3 nV/√Hz, 0.6 nV/√Hz and 0.4 nV/√Hz at 1 Hz, 10 Hz and 100 Hz, respectively. The output voltage drift was also characterized and a stability of ±25 µV over 3 h was obtained. In order to better appreciate the performance of the low-noise voltage source that we have designed, its noise performances were compared with those of a set-up based on one of the best low-noise solid-state voltage regulators available on the market. Actual measurements of the current noise in a type-II superlattice photodetector are reported in which the programmable source was used to provide the voltage bias to the device.
High Hydrogen Evolution Reaction (HER) and Hydrogen Oxidation Reaction (HOR) Activity RhxSy Catalyst Synthesized with Na2S for Hydrogen-Bromine Fuel Cell
Authors: Li Yuanchao , Nguyen Trung Van
Published: August 2020

A RhxSy/C catalyst with high mass-specific electrochemical surface area (ECSA/mass), high hydrogen oxidation reaction (HOR)/hydrogen evolution reaction (HER) activity, and high Nafion® ionomer-affinity was synthesized and evaluated. A new sulfur source, Na2S instead of (NH4)2S2O3, was applied to prepare the rhodium sulfide precursor Rh2S3 that resulted in a RhxSy catalyst with higher HOR/HER catalytic activity after thermal treatment. The higher activity was attributed to the higher quantity formation of the more active phase Rh3S4, in addition to the other active Rh17S15 phase, in the RhxSy catalyst. Using this new sulfur source, carbon substrate functionalization, and the mass-transfer-controlled nanoparticle growth process, the average particle size of this catalyst was reduced from 13.5 nm to 3.2 nm, and its ECSA/mass was increased from 9.3 m2/g-Rh to 43.0 m2/g-Rh. Finally, by applying the Baeyer–Villiger and ester hydrolysis process to convert the Nafion® ionomer-unfriendly ketone group on the carbon support surface to the Nafion ionomer-friendly carboxylic group, which increases the Nafion® affinity of this catalyst, its use in the hydrogen electrode of an H2-Br2 fuel cell resulted in a performance that is 2.5× higher than that of the fuel cell with a commercial RhxSy catalyst.
Stocking Diagrams for Silvicultural Guideline in Korean Pines and Japanese Larch
Authors: Lee Daesung , Choi Jungkee
Published: August 2020

Appropriate management of stand density is necessary to avoid wasted growing space and overcrowding-induced self-thinning and therefore to optimize profitability. We developed a Gingrich-style stocking chart for Korean red pine (Pinus densiflora), Korean white pine (P. koraiensis), and Japanese larch (Larix kaempferi) in Korea. Datasets for even-aged stands were categorized into two censored datasets via relative density based on species-specific stand density indices to assign adequate plots for tree allometry. Censored plot data for maximum density on full stocking were used to develop A-level stocking based on mean individual tree area. In censored plot data for minimum density on full stocking, individual trees represented open-grown trees, and a crown competition factor of 100 was proposed as B-level stocking. Based on parameters estimated from allometry, stocking diagrams comprising quadratic mean diameter, number of trees, and basal area were correctly expressed. A-level stocking at the same quadratic mean diameter revealed that Korean white pine had the most trees and largest basal area, while Japanese larch had the fewest trees and smallest basal area. In contrast, B-level stocking disclosed that Japanese larch had the most trees and basal area, whereas Korean white pine had the fewest trees and smallest basal area. The stocking diagrams suggest that silvicultural treatments for these species should be species-specific.
Limited Effects of Long-Term Repeated Season and Interval of Prescribed Burning on Understory Vegetation Compositional Trajectories and Indicator Species in Ponderosa Pine Forests of Northeastern Oregon, USA
Authors: Zald Harold S. J. , Kerns Becky K. , Day Michelle A.
Published: August 2020

Fire exclusion has dramatically altered historically fire adapted forests across western North America. In response, forest managers reduce forest fuels with mechanical thinning and/or prescribed burning to alter fire behavior, with additional objectives of restoring forest composition, structure, and ecosystem processes. There has been extensive research on the effects of fuel reduction and restoration treatments on trees, fuels, regeneration, and fire behavior; but less is known about how these treatments influence understory vegetation, which contains the majority of vascular plant diversity in many dry conifer forests. Of particular interest is how understory vegetation may respond to the season and interval of prescribed burning. The season and interval of prescribed burning is often determined by operational constraints rather than historical fire regimes, potentially resulting in fire conditions and burn intervals to which native plants are poorly adapted. In this study, we examined how understory vegetation has responded to season and interval of prescribed burning in ponderosa pine (Pinus ponderosa) forests in the Blue Mountains of northeastern Oregon, USA. Using over a decade (2002–2015) of understory vegetation data collected in stands with different intervals (5 versus 15 year) and seasons (spring versus fall) of prescribed burning, we quantified how season and interval of prescribed burning has influenced understory vegetation compositional trajectories and indicator species over time. Season of prescribed burning resulted in different understory communities and distinct trajectories of understory composition over time, but interval of burning did not. Indicator species analysis suggests fall burning is facilitating early seral species, with native annual forbs displaying ephemeral responses to frequent burning, while invasive cheatgrass (Bromus tectorum) increased in abundance and frequency across all treatments over time. These findings indicate that understory vegetation in these ecosystems are sensitive to seasonality of burning, but the responses are subtle. Our findings suggest season and interval of prescribed burning used in this study do not result in large changes in understory vegetation community composition, a key consideration as land managers increase the pace and scale of prescribed fire in these forests.