bluuebunny/crossref_metadata_2025 huggingface dataset:
An Outline Picture of a Growing and Rotating Planck Universe with Emerging Dark Foam
Authors: Seshavatharam U. V. S. , Lakshminarayana S.
Published: June 2020

With reference to Planck scale, Mach’s relation, increasing support for large scale cosmic anisotropy and preferred directions and by introducing two new parameters Gamma and Beta, right from the beginning of Planck scale, we make an attempt to estimate ordinary matter density ratio, dark matter density ratio, mass, radius, temperature, age and expansion velocity (from and about the bay universe in all directions). We would like suggest that, from the beginning of Planck scale, 1) Dark matter can be considered as a kind of cosmic foam responsible for formation of galaxies.  2) Cosmic angular velocity is directly proportional to squared cosmic temperature. 3) Cosmic expansion velocity increases with decreasing total matter density ratio. 4) There is no need to consider dark energy for understanding cosmic acceleration.
A Play with Four Virtual Gravitational Constants Associated with the Four Basic Interactions
Authors: Seshavatharam U. V. S. , Lakshminarayana S.
Published: June 2020

When heavenly bodies are made up of tiny atoms, it is imperative to find the correlations that might exist among ‘atoms’ and ‘heavenly body’ as a whole. In this context, by considering three virtual gravitational constants assumed to be associated with the three atomic interactions i.e. (electromagnetic, strong and weak interactions) and by considering four basic semi empirical (reference) relations pertaining to the four gravitational constants, a bold attempt is made to estimate the Newtonian gravitational constant (GN). Its fitted and recommended values are 6.679855x10-(11) m3/kg/sec2 and 6.67408x10-(11) m3/kg/sec2 respectively and error is -0.08653%. As current unification paradigm is failing in estimating (GN) from atomic and nuclear physical constants, our work can be recommended for further study.
Open String under the Modified Born-Infeld Field
Authors: Kim Aeran
Published: June 2020

In this article we consider the two end-points of the string to be attached to D-brane with the different Born-Infeld field strength F and calculate the total momenta for the special case.
A 19-Years Period (2000-2018) Dataset of Annual and Monthly Spatial Distribution of Rainfall and Average Air Temperature in a Temperate Region for Climate Change Studies
Authors: Pellegrini Marco
Published: June 2020

Aims: Temperature changes in the air, land and ocean together with the hydrological cycle and changing precipitation patterns are some of the topics assessed by scientist all over the world in order to study the signals of a changing climate. As the impacts of climate change are expected to be noticed both at global and local scale, a dataset of real-world precipitation and average air temperature at regional scale spanning a period of 19 years is provided and described in the present paper.

Study Design: Starting from cumulative precipitation and average air temperature data, a set of annual and monthly spatially distributed maps have been generated in order to provide the scientific community with regional-scale data related to a temperate climate area.

Place and Duration of Study: Marche Region, East-Central Italy, between January 2000 and December 2018.

Methodology: We used in-situ rainfall and air temperature data provided by Marche Region (Italy) Security and Civil Protection Department in the framework of the regional meteorological and hydrological monitoring network (SIRMIP). SIRMIP network is composed of a mechanical and a telemetric sensing system. SIRMIP network consists of, among others, 230 rain gauges and 137 thermometers.

Rainfall and air temperature data have been interpolated on a 1 km-resolution regular grid using Inverse Distance Weighting (IDW) spatial interpolation. Temperature data were further processed through a linear regression using elevation from a high-resolution digital terrain model (DTM).

Results: The generated dataset described in this paper consists of 228 monthly- and 19 annual-spatially distributed maps of rainfall and air temperature.
Effect of Deformation on the Mechanical Properties of Sn-5wt%Sb Alloy
Authors: Khoreem Sadiq H. , Meftah Abdo M. , Alnahari T. T.
Published: June 2020

Sn–5wt%Sb is one of the materials considered for replacing Pb-bearing alloys in electronic packaging. The mechanical response of Sn–5wt% Sb solder alloy has been tested under different strain rates and three deformation temperatures. The behavior of true strain–time of Sn–5wt% Sb solder alloy has been investigated over strain rates of and deformation temperatures of 313, 333, and 353 K. Three-load creep tests were carried out at each temperature for of the wire samples to alloys. The deformation behavior and grain growth mechanism were investigated by strain-time curve analysis and microstructure observations. The results obtained show that the general characteristics of strain-time curve and microstructure of Sn-5wt% Sb alloy sensitively depend on the deformation temperature and strain rate. New free grains have been nucleated in microstructures in the process of dynamic recrystallization. These grains grow during deformation, forming coarser structure and elongation. The dynamic recrystallization and grain growth increase with increasing deformation temperature and decreasing strain rate. From the steady state creep rate the stress exponent is described in terms of the heat treatment temperatures. The stress exponent (n) were determined to clarify the deformation mechanism. Based on the n values, it is suggested that the rate controlling creep-deformation mechanism is dislocation climb. This study revealed that the solder alloy Sn–5wt%Sb have potential to give a good combination of higher creep resistance and rupture time.
Self Potential (SP) and Resistivity Methods of Discriminating Lithologies in a Landslide Areas of Ohafia Town, Nigeria
Authors: N. Nwankwo Cyril , Emujakporue Godwin O.
Published: June 2020

This research presents the application of geophysical self-potential (SP) and resistivity methods in evaluating subsurface phenomenon in Ohafia Area. Two communities were covered with three profile lines of 200 m spread occupied in each location. The data were acquired using ABEM SAS 300C Terrameter and later processed with EarthImager 1D inversion modelling software. Self-Potential values ranged from -107.8 to 112.3 mV in Amaekpu and -100 to 150 mV in Elu area. Positive SP values indicated lithologies with low permeability while negative SP values showed permeable lithologies. Six geologic layers were inferred for Amaekpu area while seven layers were inferred from Elu area. Layer 1, 3 and 5 are low permeable lithologies while Layer 2, 4 and 6 are permeable intervals in Amaekpu. In Elu, Layers 1, 3, 5 and 7 are having low permeability while Layers 2, 4 and 5 are highly permeable lithologies. Lithologic intervals inferred from inverted resistivity data which include sands, sandstones and gravels conformed with regions having negative SP values. Similarly, depth intervals identified as topsoil, siltstones and clay conformed with positive SP values.
Assessment of Radiation Exposure Level from Some Scrap Metal Dumpsites in Nasarawa State, Nigeria
Authors: Kerinja S. S. , Ibrahim U. , Yusuf S. D. , Idris M. M. , Mundi A. A.
Published: June 2020

In this study, the radiation exposure rate emanating from the scrap metals dumpsite was assessed using an Interceptor Spectroscopic personal radiation detector (SPRD). Sixteen (16) scrap metal dumpsites were selected at random across four Local Government Areas (Nasarawa, Lafia, Akwanga, and Keffi) of Nasarawa State, Nigeria. The gamma activity level in µrem/hr on three (3) randomly selected points on each of the scrap metal dumpsites was determined. A reading was taken on point 100 m away from each of the scrap metal dumpsite. Results show that the highest annual effective dose equivalent was observed in Akwanga (AKW4) scrap metal dumpsite with an annual effective dose equivalent of 0.2167 mSv/yr. The scrap metal dumpsite with the lowest annual effective dose equivalent was observed in Lafia (LAF3) and (LAF4) with an annual effective dose equivalent of 0.0613 mSv/yr. The excess lifetime cancer risk of 0.7585 × 10-3 was the highest value recorded in AKW4, while the lowest value was found to be 0.2146 × 10-3 in LAF3 and LAF4. The control radiation exposure level, 100 m from scrap metal dumpsites, shows the value of gamma activity level and annual effective dose equivalent obtained is ranged between 13 µrem/hr and 0.1594 mSv/yr respectively on location KEF1 to 3 µrem/hr and 0.0368 mSv/yr on locations LAF2 and LAF3 respectively. The annual effective dose equivalent values obtained were below the ICRP dose limit of 1 mSv/yr, indicating that, the environments around these scrap metal dumpsites are safe. The excess lifetime cancer risk value (ELCR) obtained in some locations is higher than the world average value of 0.29 × 10-3. Therefore, we recommend that scavengers, workers at the scrap dumpsites are to minimise the period of their stay within the dumpsites, and also the residential homes are to maintain a distance of 500 meters around the scrap metal dumpsites so as to minimise the risk of developing any health problem relating to cancer in future.
On the Magnetic Field Spectrum and Its Fluctuations in a Primeval Cold Plasma in Thermal Equilibrium
Authors: Caruso Francisco , Oguri Vitor , Silveira Felipe
Published: June 2020

This work reassesses previous results and generalizes the expression for the low-frequency spectrum of magnetic fields fluctuations in a thermal plasma, that was previously obtained within the framework of the fluctuation-dissipation theorem. The new approach presented here is able to avoid any approximation yielding a unique expression that covers both the low- and high-frequency spectrum, without the need of procedures to smooth the junction between the two limit frequency regions formerly used. Also, the simultaneous dependence of this intensity on the plasma and on the collisional frequencies is discussed. Finally, the total emitted plasma energy is compared to the Stefan-Boltzmann law of a pure black-body.
A Database of Ionic Transport Characteristics for Over 29 000 Inorganic Compounds
Authors: Zhang Liwen , He Bing , Zhao Qian , Zou Zheyi , Chi Shuting , Mi Penghui , Ye Anjiang , Li Yajie , Wang Da , Avdeev Maxim , Adams Stefan , Shi Siqi
Published: June 2020

Transport characteristics of ionic conductors play a key role in the performance of electrochemical devices such as solid‐state batteries, solid‐oxide fuel cells, and sensors. Despite the significance of the transport characteristics, they have been experimentally measured only for a very small fraction of all inorganic compounds, which limits the technological progress. To address this deficiency, a database containing crystal structure information, ion migration channel connectivity information, and 3D channel maps for over 29 000 inorganic compounds is presented. The database currently contains ionic transport characteristics for all potential cation and anion conductors, including Li+, Na+, K+, Ag+, Cu(2)+, Mg2+, Zn2+, Ca2+, Al3+, F−, and O2−, and this number is growing steadily. The methods used to characterize materials in the database are a combination of structure geometric analysis based on Voronoi decomposition and bond valence site energy (BVSE) calculations, which yield interstitial sites, transport channels, and BVSE activation energy. The computational details are illustrated on several typical compounds. This database is created to accelerate the screening of fast ionic conductors and to accumulate descriptors for machine learning, providing a foundation for large‐scale research on ion migration in inorganic materials.
Micro‐ and Nanostructured Lead Halide Perovskites: From Materials to Integrations and Devices
Authors: Wang Kaiyang , Xing Guichuan , Song Qinghai , Xiao Shumin
Published: June 2020

In the past decade, lead halide perovskites have been intensively explored due to their promising future in photovoltaics. Owing to their remarkable material properties such as solution processability, nice defect tolerance, broad bandgap tunability, high quantum yields, large refractive index, and strong nonlinear effects, this family of materials has also shown advantages in many other optoelectronic devices including microlasers, photodetectors, waveguides, and metasurfaces. Very recently, the stability of perovskite devices has been improved with the optimization of synthesis methods and device architectures. It is widely accepted that it is the time to integrate all the perovskite devices into a real system. However, for integrated photonic circuits, the shapes and distributions of chemically synthesized perovskites are quite random and not suitable for integration. Consequently, controlled synthesis and the top‐down fabrication process are highly desirable to break the barriers. Herein, the developments of patterning and integration techniques for halide perovskites, as well as the structure/function relationships, are systematically reviewed. The recent progress in the study of optical responses originating from nanostructured perovskites is also presented. Lastly, the challenges and perspective for nanostructured‐perovskite devices are discussed.
C3‐Thioester/‐Ester Substituted Linear Dienones: A Pluripotent Molecular Platform for Diversification via Cascade Pericyclic Reactions
Authors: Bankura Abhijit , Naskar Sandip , Roy Chowdhury Sabyasachi , Maity Rajib , Mishra Sabyashachi , Das Indrajit
Published: June 2020

Substituted oxabicyclo derivatives bearing two quaternary carbon centers and five contiguous stereocenters have been synthesized from C3‐thioester/‐ester substituted dienones, a simple and linear pluripotent molecular platform. The conversion proceeds from neat reactants, possibly via a thermally‐driven pericyclic cascade manifold involving sequential (E)‐s‐trans to (E)‐s‐cis isomerization, oxa‐6π‐electrocyclization, and intermolecular, regioselective [4π+2π] cycloaddition. The proposed mechanism has been substantiated by intermediate trapping experiments and DFT studies. Such dienones have also been exploited to effect stereoselective cross Diels‐Alder cycloadditions with olefins and sequential Diels‐Alder/retro‐Diels‐Alder reactions with activated alkynes. The reaction is greatly influenced by the substituent effect exerted by the C3‐thioester/‐ester group.

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Photocatalyst‐Free Visible‐Light Enabled Synthesis of Substituted Pyrroles from α‐Keto Vinyl Azides
Authors: Borra Satheesh , Borkotoky Lodsna , Newar Uma Devi , Das Babulal , Maurya Ram Awatar
Published: June 2020

An efficient photocatalyst‐free visible light enabled synthesis of substituted pyrroles from α‐keto vinyl azides (readily prepared via Knoevenagel condensation of phenacyl azides with 2‐oxo‐2H‐chromene‐3‐carbaldehydes) was developed. The reaction proceeds through a denitrogenative photodecomposition of α‐keto vinyl azides, 1,3‐amino group migration, and coupling of intermediates with secondary amines.

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Coronavirus in Continuous Flux: From SARS‐CoV to SARS‐CoV‐2
Authors: Dong Yetian , Dai Tong , Liu Jun , Zhang Long , Zhou Fangfang
Published: June 2020

The world is currently experiencing a global pandemic caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), which causes severe respiratory disease similar to SARS. Previous studies have suggested that SARS‐CoV‐2 shares 79% and 96% sequence identity to SARS‐CoV and to bat coronavirus RaTG13, respectively, at the whole‐genome level. Furthermore, a series of studies have shown that SARS‐CoV‐2 induces clusters of severe respiratory illnesses (i.e., pneumonia, acute lung injury, acute respiratory distress syndrome) resembling SARS‐CoV. Moreover, the pathological syndrome may, in part, be caused by cytokine storms and dysregulated immune responses. Thus, in this work the recent literature surrounding the biology, clinical manifestations, and immunology of SARS‐CoV‐2 is summarized, with the aim of aiding prevention, diagnosis, and treatment for SARS‐CoV‐2 infection.
Enabling Deformable and Stretchable Batteries
Authors: Mackanic David G. , Kao Michael , Bao Zhenan
Published: June 2020

Deformable energy storage devices are needed to power next‐generation wearable electronics that interface intimately with human skin. Currently, deformable energy storage devices demonstrate poor performance compared to their rigid lithium‐ion counterparts, forcing wearable manufacturers to design their devices around bulky battery compartments. However, technological advances to create deformable batteries at the component and device level have yielded continuous improvement in stretchable batteries over the last five years. In this Essay, the major strategies at the component and device level that have been successfully employed to create stretchable batteries are reviewed. The outstanding challenges facing deformable energy storage are also discussed, namely, energy density, packaging, delamination, device integration, and manufacturing. This Essay will give researchers who are interested in contributing to the development of deformable batteries a cursory understanding of the most successful strategies to date, and provide insights into the most important directions to pursue in the future.
Telecommunications infrastructure in Australia
Authors: Madsen Andrew , de Percy Michael
Published: June 2020

This paper considers Australia’s approach to telecommunications infrastructure from the perspectives of the policy official and the public administration scholar. From the official’s perspective, the approach has been successful in stimulating private sector investment in many markets. This has been achieved by promoting open competition and where necessary establishing a government business enterprise as a transitional measure to build and operate a next‐generation National Broadband Network (NBN) to provide high‐speed fixed‐line broadband to all Australian premises by 2020. From the academic perspective, however, the approach reveals the shifting balances between political objectives and market challenges. This paper consists of three main parts. The first is an introduction by a former senior public servant turned public administration scholar. The second is from a policy official and provides an overview of the Australian telecommunications market, starting with some historical context, the deregulation in the 1990s and the privatisation of the former government‐owned telecommunications incumbent, Telstra. The third is from a public administration scholar and provides a short complementary critique of Australia’s communications policy. The paper discusses, from different perspectives, the policy settings that have been adopted to support infrastructure competition and investment in the Australian telecommunications market, including the development of the NBN.
Self‐Assembly of Perovskite CsPbBr3 Quantum Dots Driven by a Photo‐Induced Alkynyl Homocoupling Reaction
Authors: Li Hongbo , Liu Xiangdong , Ying Qifei , Wang Chao , Jia Wei , Xing Xing , Yin Lisha , Lu Zhenda , Zhang Kun , Pan Yue , Shi Zhan , Huang Ling , Jia Dianzeng
Published: June 2020

Herein, we report the facile growth of three‐dimensional CsPbBr3 perovskite supercrystals (PSCs) self‐assembled from individual CsPbBr3 perovskite quantum dots (PQDs). By varying the carbon chain length of a surface‐bound ligand molecule, 1‐alkynyl acid, different morphologies of PSCs were obtained accompanied by an over 1000‐fold photoluminescence improvement compared with that of PQDs. Systematic analyses have shown, for the first time, that under UV irradiation, CsBr, the byproduct formed during PQDs synthesis, could effectively catalyze the homocoupling reaction between two alkynyl groups, which further worked as a driving force to push forward the self‐assembly of PQDs.
Tailoring A Poly(ether sulfone) Bipolar Membrane: Osmotic‐Energy Generator with High Power Density
Authors: Sun Yue , Dong Tiandu , Lu Chunxin , Xin Weiwen , Yang Linsen , Liu Pei , Qian Yongchao , Zhao Yuanyuan , Kong Xiang‐Yu , Wen Liping , Jiang Lei
Published: June 2020

Osmotic energy, obtained through different concentrations of salt solutions, is recognized as a form of a sustainable energy source. In the past years, membranes derived from asymmetric aromatic compounds have attracted attention because of their low cost and high performance in osmotic energy conversion. The membrane formation process, charging state, functional groups, membrane thickness, and the ion‐exchange capacity of the membrane could affect the power generation performance. Among asymmetric membranes, a bipolar membrane could largely promote the ion transport. Here, two polymers with the same poly(ether sulfone) main chain but opposite charges were synthesized to prepare bipolar membranes by a nonsolvent‐induced phase separation (NIPS) and spin‐coating (SC) method. The maximum power density of the bipolar membrane reaches about 6.2 W m−2 under a 50‐fold salinity gradient, and this result can serve as a reference for the design of bipolar membranes for osmotic energy conversion systems.
Spectral and molecular docking studies of nucleic acids/protein binding interactions of a novel organometallic palladium (II) complex containing bioactive PTA ligands: Its synthesis, anticancer effects and encapsulation in albumin nanoparticles
Authors: Lighvan Zohreh Mehri , Khonakdar Hossein Ali , Heydari Abolfazl , Rafiee Mina , Jahromi Maryam Dehdashti , Derakhshani Ali , Momtazi‐Borojeni Amir Abbas
Published: June 2020

The organometallic palladium complex with nitrogen‐containing heterocycles is a potent antitumor agent. Coordination of phosphorus ligands to organometallic complexes increases their hydrophilicity, promotes ligand−DNA interactions and damage level to cancer cells, and blocks division in target cells. In this study, a phosphaadamantane palladium complex ([Pd{(C,N)‐ (C12H8NH2)} (PTA) Cl], PTA = 1,3,5‐Triaza‐7‐phosphaadamantane) (2) was synthesized via the reaction of biologically active PTA with binuclear palladacycles [Pd2{(C,N)‐(C12H8NH2)}2(μ‐Cl)2] (1). In vitro studies of the complex with DNA (calf‐thymus) explored by UV–Vis, emission titration, circular dichroism and helix melting methods showed that the complex interacts with DNA via an intercalative mechanism. Furthermore, competitive binding studies using warfarin, digoxin and ibuprofen site markers containing definite binding sites revealed the binding of the complex to site I on bovine serum albumin. The in vitro release mechanism of the palladium complex exhibited a biphasic pattern characterized by an initial burst release followed by a slower sustained release. Ultimately, in vitro evaluation of cytotoxicity and cell death showed that the complexes were able to decrease the viability of human cancer cell lines (MCF‐7 and Jurkat) in a dose‐dependent manner, but lower decreases were observed in the viability of normal fibroblast cells ASF‐4 at the dosages evaluated. Finally, the order of in vitro anticancer activities was found to be consistent with the DNA‐binding affinities.
Silica‐filled NR compounds prepared by dry and wet masterbatches with different mixing times
Authors: Ryu Changseok , Yang Jae‐Kyoung , Park Wonhyeong , Kim Sun Jung , Kim Do Il , Seo Gon
Published: June 2020

Silica‐filled NR compounds are prepared by mixing rubber with organic‐networked silica and additives such as curatives, processing and coupling agents, and stabilizer in a dried state (dry‐mixed NR, DNR) and mixing a silica‐NR wet masterbatch prepared in liquid phase with the additives (wet‐mixed NR, WNR). The effects of mixing method and time of DNR and WNR compounds on their cure, process, tensile, and dynamic properties are investigated. The mixing of DNR crushes silica aggregates to smaller ones, but also forms occasionally large ones, while the mixing of WNR produces small aggregates without forming larger ones because silica aggregates are already covered with rubber. The high silica dispersion, suppressed silica aggregation, low Payne effect, and low‐loss modulus of the WNR compounds prepared by mixing for a sufficient time result in their low viscosity, high scorch safety, and low rolling resistance without sacrificing other rubber properties.
Cortical and medullary morphology of the tibia
Authors: Taylor Carolyn E. , Henninger Heath B. , Bachus Kent N.
Published: June 2020

Bone resorption caused by stress shielding and insufficient bone‐implant contact continues to be problematic for orthopedic endoprostheses that utilize osseointegration (OI) for skeletal fixation. Morphologic analyses have helped combat this issue by defining anatomic parameters to optimize endoprosthesis loading by maximizing bone‐implant contact. These studies have not typically included diaphyseal medullary morphology, as this region is not pertinent to total joint replacement. To the contrary, percutaneous OI endoprostheses for prosthetic limb attachment are placed in the diaphysis of the long bone. This study examined the cortical and medullary morphology of 116 fresh‐frozen human cadaveric tibia using computed tomography. Anatomic landmarks were selected and custom MATLAB scripts were used to analyze the cross‐sectional cortical and medullary morphology normalized to biomechanical length (BML). BML measured the distance between the tibial plateau and the tibial plafond. Properties such as cortical thickness, medullary diameter, and circularity of the medullary canal were quantified. We tested the influence of sex and laterality on morphology, and examined variations along the length of the bone. Results showed that while both sex and laterality impacted the location of anatomic landmarks, only sex influenced cross‐sectional morphology. Overall, morphology significantly affected shape along the length of the bone for all examined properties except medullary circularity. This analysis found that distal to 35% BML, the canal is conducive to a circular implant, with medullary diameter ranging from 13 to 32 mm between 20 and 80% BML. A large size range is necessary for sufficient implant contact in order to accommodate residual limb length after amputation.
Statistischer Maßstabseffekt und seine Bedeutung für die Zuverlässigkeit im Stahlbau
Authors: Li Zheng , Pasternak Hartmut
Published: June 2020

Mikroskopische Imperfektionen im Werkstoff führen dazu, dass die Werte mechanischer Eigenschaften von Bauteilen gewissen Auftretenswahrscheinlichkeiten unterliegen. Mit zunehmendem Volumen erhöht sich die Anzahl der mikroskopischen Defekte, was sich direkt in einer veränderten makroskopischen Festigkeit niederschlägt. Dieses Phänomen ist unter der Bezeichnung statistischer Maßstabseffekt bekannt. Eine solche Maßstabsabhängigkeit kann durch ein stochastisches Werkstoffmodell gut erfasst werden. In diesem Beitrag wurde das Bündel‐Kettenglied‐Modell, das auf einem stochastischen Werkstoffmodell nach Weibull‐ und Lognormalverteilung basiert, entwickelt und eine Möglichkeit zur Bestimmung des statistischen Maßstabseffekts durch numerische Verfahren angegeben. Um den statistischen Maßstabseffekt im Stahlbau zu demonstrieren, werden die Biegeversuche mit unterschiedlichen Probengrößen durchgeführt. Dieser Beitrag beschreibt – als erster von zwei Teilen – Forschungsergebnisse über den statistischen Maßstabseffekt und die entsprechende Zuverlässigkeit im Stahlbau.
Magnetic Precipitation: A New Platform for Protein Purification
Authors: Santos Raquel dos , Iria Inês , Manuel Ana M. , Leandro Ana P. , Madeira Catarina A. C. , Goncalves Joao , Carvalho Ana Luísa , Roque Ana Cecília A.
Published: June 2020

One of the trends in downstream processing comprises the use of “anything‐but‐chromatography” methods to overcome the current downfalls of standard packed‐bed chromatography. Precipitation and magnetic separation are two techniques already proven to accomplish protein purification from complex media, yet never used in synergy. With the aim to capture antibodies directly from crude extracts, a new approach combining precipitation and magnetic separation is developed and named as affinity magnetic precipitation. A precipitation screening, based on the Hofmeister series, and a commercial precipitation kit are tested with affinity magnetic particles to assess the best condition for antibody capture from human serum plasma and clarified cell supernatant. The best conditions are obtained when using PEG3350 as precipitant at 4 °C for 1 h, reaching 80% purity and 50% recovery of polyclonal antibodies from plasma, and 99% purity with 97% recovery yield of anti‐TNFα mAb from cell supernatants. These results show that the synergetic use of precipitation and magnetic separation can represent an alternative for the efficient capture of antibodies.
Mushroom DNA barcoding project: Sequencing a segment of the 28S rRNA gene
Authors: Horn Ivo R. , Verleg Peter A. , Ibrahim Nafiesa Z. , Soeleman Khadiedjah , van Kampen Floris , Ruesen Mia O. , Reulen Naïsha M. , Breij Henk , Bakker Roderick J. , Gravendeel Barbara
Published: June 2020

DNA barcoding is an important molecular methodology for species identification that was developed over the last two decades and it should be covered in the biology bachelor curriculum. Here, we present an example of DNA barcoding by sequencing a segment of the 28S nuclear ribosomal large subunit rRNA gene of wild mushrooms and framing the education in a project form for undergraduate students in biology. Students perform this project in 6–8 weeks, which also includes preparing a poster, writing a report and presenting a paper related to the work in a journal club format. First, fieldwork in the Netherlands was carried out, during which students collected mushrooms under supervision of a professional mycologist with the goal to (a) verify morphologically based identifications with a molecular method and (b) assess phylogenetic relationships of the different species collected. Next, DNA extractions and quantitation were performed, PCR amplification was done, and samples were sent out for Sanger sequencing. Students aligned and analyzed the sequences using BLAST and Geneious and subsequently created a phylogenetic tree. In case of collecting DNA barcodes of an earlier sequenced species, students could upload the data to a repository established for facilitation of future research projects. The method described is very robust, reagents and equipment are readily available, and costs are relatively low. In addition, the results can be compared to published fungal phylogenetic trees.
Developing a mobile application‐based particle image velocimetry tool for enhanced teaching and learning in fluid mechanics: A design‐based research approach
Authors: Minichiello Angela , Armijo David , Mukherjee Sarbajit , Caldwell Lori , Kulyukin Vladimir , Truscott Tadd , Elliott Jack , Bhouraskar Aditya
Published: June 2020

A robust and intuitive understanding of fluid mechanics—the applied science of fluid motion—is foundational within many engineering disciplines, including aerospace, chemical, civil, mechanical, naval, and ocean engineering. In‐depth knowledge of fluid mechanics is critical to safe and economical design of engineering applications employed globally everyday, such as automobiles, aircraft, and sea craft, and to meeting global 21st century engineering challenges, such as developing renewable energy sources, providing access to clean water, managing the environmental nitrogen cycle, and improving urban infrastructure. Despite the fundamental nature of fluid mechanics within the broader undergraduate engineering curriculum, students often characterize courses in fluid mechanics as mathematically onerous, conceptually difficult, and aesthetically uninteresting; anecdotally, undergraduates may choose to opt‐out of fluids engineering‐related careers based on their early experiences in fluids courses. Therefore, the continued development of new frameworks for engineering instruction in fluid mechanics is needed. Toward that end, this paper introduces mobile instructional particle image velocimetry (mI‐PIV), a low‐cost, open‐source, mobile application‐based educational tool under development for smartphones and tablets running Android. The mobile application provides learners with both technological capability and guided instruction that enables them to visualize and experiment with authentic flow fields in real time. The mI‐PIV tool is designed to generate interest in and intuition about fluid flow and to improve understanding of mathematical concepts as they relate to fluid mechanics by providing opportunities for fluids‐related active engagement and discovery in both formal and informal learning contexts.
Wound healing after excision of subcutaneous tumors treated with near‐infrared photoimmunotherapy
Authors: Rosenberg Adrian , Inagaki Fuyuki , Kato Takuya , Okada Ryuhei , Wakiyama Hiroaki , Furusawa Aki , Choyke Peter L. , Kobayashi Hisataka
Published: June 2020

Near‐infrared photoimmunotherapy (NIR‐PIT) is a novel cancer therapy that employs a combination of infrared light and tumor‐targeted monoclonal antibody‐photoabsorber conjugates to cause both direct tumor necrosis and immunogenic cell death. NIR‐PIT may have potential in the perioperative setting before surgery, and therefore it is important to know the effect of NIR‐PIT on wound healing. Fifty mice were implanted with subcutaneous xenografts of N87 human gastric cancer cells, and tumors were excised after reaching a predetermined size. After excision, 30 mice were split into three groups: Controls, NIR‐PIT 1 day prior to surgery and NIR‐PIT 3 days prior to surgery. The quantity of reactive oxygen species (ROS) in each wound was measured on Postoperative Days 2 and 4, and mice were monitored weekly for 4 weeks for evidence of local tumor recurrence as well as clinical evidence of wound healing complications (eg, dehiscence, infection). The remaining 20 mice (10 controls, 10 treated with NIR‐PIT 1 day prior to surgery) were sacrificed on either Postoperative Day 7 or 14, the skin around wounds were excised, and tensile strength was measured with a digital force gauge. There were no significant differences between treatment and control groups with respect to wound ROS levels, wound tensile strength, local tumor recurrence, or postoperative complication rates (P > .05). In conclusion, neoadjuvant (pre‐operative) NIR‐PIT shows no evidence of adverse wound healing effects, and it is likely a safe adjunctive treatment to surgery. Postoperative use of NIR‐PIT merits investigation.
Cationic RuII Cyclopentadienyl Complexes with Antifungal Activity against Several Candida Species
Authors: Golbaghi Golara , Groleau Marie‐Christine , López de los Santos Yossef , Doucet Nicolas , Déziel Eric , Castonguay Annie
Published: June 2020

Fungal infections, including those caused by antifungal‐resistant Candida, are a very challenging health problem worldwide. Whereas different ruthenium complexes were previously studied for their anti‐Candida potential, Ru‐cyclopentadienyl complexes were overlooked. Here, we report an antifungal activity assessment of three Ru‐cyclopentadienyl complexes with some insights into their potential mode of action. Among these complexes, only the cationic species [Ru‐ACN]+ and [Ru‐ATZ]+ displayed a significant antifungal activity against different Candida strains, notably against the ones that did not respond to one of the most currently used antifungal drugs fluconazole (FCZ). However, no apparent activity was observed for the neutral species, Ru−Cl, thus indicating the important role of the cationic backbone of these complexes in their biological activity. We suggest that reactive oxygen species (ROS) generation might be involved in the mechanism of action of these complexes as, unlike neutral Ru−Cl, [Ru‐ACN]+ and [Ru‐ATZ]+ could generate intracellular concentration‐dependent ROS. We also observed a correlation between the ruthenium cellular uptake, ROS generation and fungal growth inhibitory activity of the compounds. Furthermore, docking simulations showed that the CYP51 enzyme can form more energetically favorable complexes with [Ru‐ATZ]+ than fluconazole (FCZ); this suggests that CYP51 inhibition could also be considered as a potential mode of action.
Closure of long‐standing oroantral fistula: Surgical challenge in medically compromised patient—A case report
Authors: Ramanathan Arvind , Acharya Vishak
Published: June 2020

A systematic treatment plan of controlling chronic sinusitis, optimizing systemic health, and appropriate selection of surgical technique are essential requirements for successful closure of oroantral fistula.
Hepar Lobatum carcinomatosum: A rare cause of portal hypertension
Authors: Mathis Guillaume , Felli Emanuele , Mutter Didier , Pessaux Patrick
Published: June 2020

Hepar lobatum carcinomatosum is a rare form of major hepatic dysmorphia secondary to metastatic breast cancer. This condition seems to be related to the obstruction of portal vessels by tumor cells responsible of possible secondary portal hypertension without underlying cirrhosis.
Acute interstitial nephritis with only three doses of pantoprazole
Authors: Samal Subhankar , Singhania Namrata , Bansal Saurabh , Singhania Girish
Published: June 2020

Several antibiotics, proton pump inhibitors, and nonsteroidal anti‐inflammatory drugs can cause acute interstitial nephritis. This is not dose‐dependent, and recurrence can occur with a second exposure of the same drug. Stopping the culprit is critical for successful management.
Engineering Bifunctional Host Materials of Sulfur and Lithium‐Metal Based on Nitrogen‐Enriched Polyacrylonitrile for Li–S Batteries
Authors: Dai Zudian , Wang Mei , Zhang Yin , Wang Boya , Luo Hang , Zhang Xuemei , Wang Qian , Zhang Yun , Wu Hao
Published: June 2020

Lithium–sulfur batteries (LSBs) still suffer from the shuttle effect on the cathode and the lithium dendrite on the anode. Herein, polyacrylonitrile (PAN) is developed into a bifunctional host material to simultaneously address the challenges faced on both the sulfur cathode and lithium anode in LSBs. For the sulfur cathode, PAN is bonded with sulfur to produce sulfurized PAN (SPAN) to avoid the shuttle effect. The SPAN is accommodated into a conductive 3D CNTs‐wrapped carbon foam to prepare a self‐supporting cathode, which improves the electronic and ionic conductivity, and buffers the volume expansion. Thereby, it delivers reversible capacity, superb rate capability, and outstanding cycling stability. For the Li‐metal anode, PAN aerogel is carbonized to give macroporous N‐doped cross‐linked carbon nanofiber that behaves as a lithiophilic host to regulate Li plating and suppress the growth of Li dendrite. Combining the improvements for both the cathode and anode realizes a remarkable long‐term cyclability (765 mAh g−1 after 300 cycles) in a full cell. It provides new opportunity to propel the practical application of advanced LSBs.
Boron Effect on Sugar‐Based Organogelators
Authors: Ludwig Andreas D. , Saint‐Jalmes Arnaud , Mériadec Cristelle , Artzner Franck , Tasseau Olivier , Berrée Fabienne , Lemiègre Loïc
Published: June 2020

The reaction of several alkylglucosides with phenyl boronic acid permitted easy access to a series of alkylglucoside phenyl boronate derivatives. This type of compound has structures similar to those of known benzylidene glucoside organogelators except for the presence of a boronate function in place of the acetal one. Low to very low concentrations of these amphiphilic molecules produced gelation of several organic solvents. The rheological properties of the corresponding soft materials characterized them as elastic solids. They were further characterized by SEM to obtain more information on their morphologies and by SAXS to determine the type of self‐assembly involved within the gels. The sensitivity of the boronate function towards hydrolysis was also investigated. We demonstrated that a small amount of water (5 % v/v) was sufficient to disrupt the organogels leading to the original alkylglucoside and phenyl boronic acid; an important difference with the stable benzylidene‐based organogelators. Such water‐sensitive boronated organogelators could be suitable substances for the preparation of smart soft material for topical drug delivery.
Female Faculty: Why So Few and Why Care?
Authors: Kamerlin Shina Caroline Lynn , Wittung‐Stafshede Pernilla
Published: June 2020

Despite slow ongoing progress in increasing the representation of women in academia, women remain significantly under‐represented at senior levels, in particular in the natural sciences and engineering. Not infrequently, this is downplayed by bringing forth arguments such as inherent biological differences between genders, that current policies are adequate to address the issue, or by deflecting this as being “not my problem” among other examples. In this piece we present scientific evidence that counters these claims, as well as a best‐practice example, Genie, from Chalmers University of Technology, where one of the authors is currently employed. We also highlight particular challenges caused by the current COVID‐19 pandemic. Finally, we conclude by proposing some possible solutions to the situation and emphasize that we need to all do our part, to ensure that the next generation of academics experience a more diverse, inclusive, and equitable working environment.
Chelating Group Enabled Palladium‐Catalyzed Regiodivergent Carbonylative Synthesis of 2,3‐Dihydroquinolin‐4(1H)‐ones
Authors: Ying Jun , Wang Jian‐Shu , Yao Lingyun , Lu Wangyang , Wu Xiao‐Feng
Published: June 2020

A new procedure on palladium‐catalyzed carbonylative cyclization of N‐(2‐pyridyl)sulfonyl (N‐SO2Py)‐2‐iodoanilines with terminal alkenes has been developed for the rapid construction of dihydroquinolin‐4(1H)‐one scaffolds. Enabled by the chelating group and using benzene‐1,3,5‐triyl triformate (TFBen) as the CO source, both aromatic and aliphatic alkenes were smoothly transformed into the corresponding 2,3‐dihydroquinolin‐4(1H)‐ones in good yields with excellent regioselectivities. Notably, the reaction of aromatic alkenes produces 2‐aryl‐2,3‐dihydroquinolin‐4(1H)‐ones, while 3‐alkyl‐2,3‐dihydroquinolin‐4(1H)‐ones were obtained when aliphatic alkenes were used. This protocol has been applied in the synthesis of antitumor agent A as well.
Genkwadane F—I, New Daphnane‐type Diterpenes from the Flower Buds of Daphne genkwa Sieb.et Zucc. Exhibit Anti‐tumor Activities via Inducing Apoptosis
Authors: Hou Xuewen , Chen Jingjie , Hou Xuefen , Gao Pinyi , Wang Jinlin , Song Shaojiang , Li Lingzhi
Published: June 2020

Summary of main observation and conclusion

Genkwadane F—I (1—4), four new diterpenes, along with four known ones (5—8), were isolated from the flower buds of D. genkwa. The structures including absolute configurations of 1—4 were determined based on the analysis of NMR and ECD calculations. All compounds were evaluated for their cytotoxicities against MCF‐7 and Hep3B cell lines, among which compounds 3 and 4 showed significant activities. Compound 4 exhibited the most potent activity with IC50 values of 1.33 μM against MCF‐7, and the IC50 values of compound 3 against MCF‐7 and Hep3B were 5.54 μM and 8.73 μM, respectively. Further studies by Hoechst 33258 staining and Annexin V/PI analysis demonstrated that compounds 3 and 4 could induce apoptosis to exhibit anti‐tumor activities.
A high efficacy and tunable white light‐emitting diode cluster with both color fidelity and nonvisual performances close to natural lights
Authors: Li Xinhao , Ding Ke , Zhong Ping , He Guoxing
Published: June 2020

A luminous efficacy model for a white light‐emitting diode (LED) cluster was developed, and five α‐opic efficacy ratios (γα,Vs) of intrinsically photosensitive retinal ganglion cells were adopted in order to quantify its nonvisual performance relative to natural light. A tunable C/A/R LED cluster, which consists of the cyan LEDs with green phosphor excited by a blue LED, the amber LEDs with green and orange phosphors excited by same blue chip, and the red LEDs, was proposed by maximizing the average luminous efficacy at correlated color temperatures (CCTs) of 2700 to 6500 K under the condition of color fidelity index (Rf) above 96 and five values of γα,V of 0.95 to 1.05. The real tunable C/A/R LED cluster with a Rf of 95 to 96, five values of γα,V of 0.97 to 1.01, and a luminous efficacy of 114 to 120 lm/W at a CCT of 2670 to 6456 K were demonstrated. Furthermore, five values of γα,V can be adjusted according to the distance from the Planckian or daylight locus on the CIE 1960 uv chromaticity diagram at different CCTs. Thus, the tunability of γα,V value of the C/A/R LED cluster at a specific CCT could be applied to different requirements for nonvisual performance.
Continued Fractions and Hankel Determinants from Hyperelliptic Curves
Authors: Hone Andrew N. W.
Published: June 2020

Following van der Poorten, we consider a family of nonlinear maps that are generated from the continued fraction expansion of a function on a hyperelliptic curve of genus g. Using the connection with the classical theory of J‐fractions and orthogonal polynomials, we show that in the simplest case g = 1 this provides a straightforward derivation of Hankel determinant formulae for the terms of a general Somos‐4 sequence, which were found in a particular form by Chang, Hu, and Xin. We extend these formulae to the higher genus case, and prove that generic Hankel determinants in genus 2 satisfy a Somos‐8 relation. Moreover, for all g we show that the iteration for the continued fraction expansion is equivalent to a discrete Lax pair with a natural Poisson structure, and the associated nonlinear map is a discrete integrable system. © 2020 the Authors. Communications on Pure and Applied Mathematics is published by Wiley Periodicals LLC.
Comparison of the Pharmacokinetics of a Fixed‐Dose Combination of Rosuvastatin/Metformin Sustained‐Release (10/1000 mg) and Separate Tablets in Healthy Male Subjects
Authors: Huh Ki Young , Kim Eunwoo , Lee Heechan , Jeon Inseung , Suh Hearan , Lee Jongsun , Lee Yunhee , Yu Kyung‐Sang , Lee SeungHwan
Published: June 2020

Fixed‐dose combination (FDC) drugs with various dose combinations for the treatment of type 2 diabetes mellitus and dyslipidemia are currently in demand. We compared the pharmacokinetic (PK) profiles of the rosuvastatin/metformin sustained‐release (10/1000 mg) FDC and separate tablets and evaluated the effect of food by randomized, open‐label, 3‐period, 6‐sequence crossover studies conducted in healthy male subjects. Subjects were randomly assigned to one of the following treatments: separate tablets of 10 mg rosuvastatin and 1000 mg metformin sustained release in the fed state and the FDC in the fasted and fed states. PK samples were collected up to 72 hours postdose for rosuvastatin, N‐desmethyl rosuvastatin, and metformin. The PK parameters were determined using a noncompartmental method, and the geometric mean ratio (GMR) and the 90% confidence interval (CI) of the treatments were calculated. A total of 35 subjects completed the study. The GMR and 90%CI of the peak concentration (Cmax) and area under the plasma concentration‐time curve from time zero to the last measurable concentration (AUClast) of the FDC and the separate tablets were within the bioequivalence criteria (0.8–1.25) for both rosuvastatin and metformin. The effect of food was statistically significant for both rosuvastatin and metformin but not expected to be of clinical significance.