bluuebunny/crossref_metadata_2025 huggingface dataset:
Solution of Linear Equations With Coefficients and Right-Hand Members in An Arithmetic Sequence
Authors: Gupta Murli M.
Published: January 2021

A general solution of a problem in linear algebra.
Hand-Held Calculators and Potential Redesign of the School Mathematics Curriculum
Authors: Pollak Henry O.
Published: January 2021

Rethinking the content and teaching of secondary mathematics in the calculator era.
Neutral and Non-Euclidean Geometry— A High School Course
Authors: Krauss Peter A. , Okolica Steven L.
Published: January 2021

Report of a promising classroom-tested alternative in high school geometry.
Problems, Problem Solving, and Strategy Games
Authors: Krulik Stephen
Published: January 2021

In problem solving you may not always reach your goal, but the search itself may prove to be more important.
The Mathematics of Genetics
Authors: Austin Joe Dan
Published: January 2021

Mendel's classic theory is extended to study “stable” populations and the extinction probabilities of such genetic diseases as cystic fibrosis.
Sharing Teaching Ideas
Authors: Johnson Joseph S.
Published: January 2021

Sharing Teaching Ideas offers practical tips on the teaching of topics related to the secondary school curriculum. We hope to include classroom-tested approaches that offer new slants on familiar subjects for the beginning and the experienced teacher. Please send an original and four copies of your ideas to the managing editor for review.
Activities: Calculator Crossword Puzzle
Authors: Goodhue Joseph F.
Published: January 2021

Materials: Eight-place pocket calculator (preferably with a memory).
Computer Classification of Triangles and Quadrilaterals—A Challenging Application
Authors: Dennis J. Richard
Published: January 2021

Are you looking for a nice way of classifying polygons? Here is one system for doing it.
The Egg Series: Using Simple Computer Models
Authors: Statz Joyce , Miller Leland
Published: January 2021

An egg-carton approach to dispelling the “black box” mysteries of computers.
New York Basic Competency Examinations
Authors: Paul Fredric
Published: January 2021

Beginning with the graduating class of June 1979. students in New York State will need to pass basic comptetency examinations in mathematics and reading to be eligible for a high school diploma.
Star Trek Logic
Authors: Lamb John
Published: January 2021

The logic of a fictional hero goes to the classroom.
More Mathemagic From a Triangle
Authors: House Peggy A.
Published: January 2021

As we rush through the business of computation and “getting the answer,” how often do we allow ourselves the luxury of simply playing with numbers? And how often do we encourage our students to play with numbers? The following excursion into magic triangles is the outcome of a recent “play period.”
Some Properties of the Calculator Square-Root Function
Authors: Dorn Carl , Councilman Samuel
Published: January 2021

Here's what you've been looking, for—a delightful exploration of a common calculator “trick” that is truly significant and open-ended.
NAEP Note: Problem Solving
Authors: Carpenter Thomas P. , Corbitt Mary Kay , Kepner Henry S. , Lindquist Mary Montgomery , Reys Robert E.
Published: January 2021

Mathematical knowledge or skills have little value if they cannot be applied to new or unfamiliar situations. For this reason, developing students’ ability to apply mathematical knowledge and skills to problem-solving situations is widely recognized as one of the major goals of mathematics instruction.
Geometric Transformations On A Microcomputer
Authors: Shilgalis Thomas W.
Published: January 2021

Computers in the geometry class? Not long ago the suggestion would have been dismissed as impractical, too costly, and not worth the elfort. The computational exercises in the usual geometry class are not sufficiently complicated to justify the use of a computer, and that objection remains valid today.
More on Subtraction Without Borrowing
Authors: Vance Irvin E.
Published: January 2021

In the March 1980 issue of the Mathe- matics Teacher, Bruce Colton presents a very nice algorithm in “Subtraction without Borrowing.”
Sharing Teaching Ideas: The Twelve Days Of Christmas And Pascal’S Triangle
Authors: Dugle Junis
Published: January 2021

This lesson was used with various algebra and geometry classes just before Christmas vacation. For the lesson. I had plenty of chalk on hand in bright colors, especially “tree green” and “ornament red, yellow, and blue." My Christmas “lecture” is just brimming with mathematics, and it keeps the students on pins and pine needles for an entire class period.
A Model for Helping Student Teachers
Authors: Campbell Patricia F. , Wheatley Grayson H.
Published: January 2021

In the sequence of courses that comprise a secondary school teacher's preparation program, the student teaching experience probably makes the most profound impression on the student. Within weeks, the student changes from a college student to a beginning teacher. The development of professional attitudes, skills, and responsibilities during that period occurs under the guidance of an experienced supervising teacher.
Writing in Mathematics Classes: A Valuable Tool for Learning
Authors: Johnson Marvin L.
Published: January 2021

American education has traditionally emphasized the three Rs—readin’, ‘rilin’, and ‘rithmetic—as the fulcrum on which the lever of learning turns in moving the rock of ignorance.
The Matrix Treatment of Certain Logic-Type Puzzles
Authors: Shoemaker Richard W.
Published: January 2021

There is a class of puzzle in which a list of statements is given and the solver is expected to determine correct associations or relationships from these clues. This type of puzzle is sometimes susceptible to a matrix or gridlike treatment where the relevant categories—such as first names, occupations, city of birth, and so on—w ill be labels for the rows or columns of one or more matrices.
The 10-Minute Mathematics Bulletin Board
Authors: Allinger Glenn D.
Published: January 2021

Bulletin boards are the crabgrass of teaching, to paraphrase a philosophical statement by Charlie Brown. The vacant, brownish wall area generates guilt (I should do something about it), frustration (I don't have the time to cut and paste), embarrassment (faded illustrations pressed into service on parents’ night), and New Year's resolutions (this summer I'll put something together). Many pamphlets and monographs with superlative artwork only further depress experienced teachers.
Euler, the Master Calculator
Authors: Taylor Jerry D.
Published: January 2021

On the bicentennial of Leonard Euler's (pronounced oiler) death, we should review some of his contributions, both to get an idea of the debt we owe to Euler and to get a feeling for the methods of this eighteenth-century mathematician. I shall present some problems and then suggest how Euler might have solved them.
Symbolic Computer Algebra: The Classroom Computer Takes a Quantum Jump
Authors: Kunkle Dan , Burch Charles I.
Published: January 2021

No one doubts that growth in computing technology has had a profound impact on our society, and certainly many interesting applications are now within the grasp of mathematics students at all levels.
Soundoff: New Federal Programs for Mathematics Education
Authors: Buccino Alphonse
Published: January 2021

Those of us who work in mathematics and science education have the sense that a national debate has been raging for some time about weaknesses in American education, especially in these subjects, and have been expecting some resolution of the debate by the federal government. The resolution appears to be at hand. This note reviews the major features of the debate and describes some of the new programs that have resulted.
Soundoff: Some Thoughts on Merit Pay
Authors: Cuoco Albert A.
Published: January 2021

The views expressed in the “Soundoff” editorials do not necessarily reflect the views of the Editorial Panel of the Mathematics Teacher or the National Council of Teachers of Mathematics. Readers are encouraged to react to these editorials by writing to the author with copies to the Mathematics Teacher for consideration in “Reader Reflections.” Please double-space all letters that are to be considered for publication. Editorials from readers are welcomed.
A Piagetian Approach to Transformation Geometry via Microworlds
Authors: Thompson Patrick W.
Published: January 2021

The project described in this article grew from a simple observation: many geometry students are unable to see anything in a diagram beyond a static presentation. They do not see the potential for “constructability,” nor do they see the possibility of augmenting the diagrams by auxiliary constructions.
Microcomputer-assisted mathematics: How to Solve the Diophantine Equation x2 + y2 = z3 With Only One Literal Symbol
Authors: Flusser Peter
Published: January 2021

Little is known of the life of the great mathematician Diophantus. We know that he lived in Alexandria, Egypt. His name was Greek, he wrote in Greek, and his heritage was mostly Greek, with perhaps some Persian influence. He may have been Egyptian.
Did Gauss Discover That, Too?
Authors: Francis Richard L.
Published: January 2021

A remarkable feature of the history of mathematics is the enormous interval that separates the posing of certain problems and their ultimate resolution. Also remarkable is the long chain of attempted solutions that spanned the many centuries. Examples of this phenomenon are the three famous problems of antiquity, which were resolved only in the modern era.
Large Integers with Small Numbers
Authors: Wallace Edward C. , Chance Joseph E.
Published: January 2021

One of the first applications of a microcomputer in the mathematics classroom is “number crunching,” This application can be of particular value with certain topics from number theory involving computations that are unreasonable using pencil and paper. We recently had occasion to discuss with students two ideas from number theory that seemed well suited to investigation with a computer. The first concerned a method for predicting the number of zeros at the end of N!. The second involved an algorithm that could be used to generate palindromic integers. Both topics came to involve computations with very large integers—so large that our microcomputers were not immediately capable of supplying a sufficient number of significant digits to allow a full exploration of the topics. Consequently, we found ourselves with an opportunity to use some mathematical skills to overcome an inherent limitation of the computers.
Where Is the Ball Going?
Authors: Ott Jack A. , Contento Anthony
Published: January 2021

This article presents a computer program that can be integrated into a lesson on inductive reasoning and suggests several ways to do so.
Making −x Meaningful
Authors: Johnson David R.
Published: January 2021

How do your algebra students read the symbol −x? Common responses are “negative x,” “minus x,” “the opposite of x,” or “the additive inverse of x.” The most common response is “negative x.” But are all these responses meaningful? Definitely not! In fact, the first two responses are very misleading, if not incorrect. In many classrooms, teachers are quite careful to name a real number less than zero (or to the left of zero on the real-number line) a negative number. Students quite easily grasp the meaning of the phrase negative number. But suddenly we bring out the expression − x and read it “negative x”! Trouble begins. Students immediately assume that this symbol stands for a number less than zero simply because its verbal name contains the word negative.
Get the Message? Cryptographs, Mathematics, and Computers
Authors: Reagan James
Published: January 2021

Most students realize that functions can be constructed to describe various physical phenomena, but it is not clear when inverses of functions are needed. One appropriate application of functions and their inverses is the coding and decoding of messages and information exchanged among people. Computers can be especially helpful in this process.
An Illustration of Limits
Authors: Johnson Jerry A.
Published: January 2021

Suppose you have two pairs of socks, one red and one blue. You are very sleepy while dressing for school and simply select two socks at random from the four in the drawer. What is the probability that your two socks match?
“O quanto é preciosa ao Compositor a Instrução Literária”: o projeto criativo em Arte explicada do contraponto de André da Silva Gomes (1752-1844)
Authors:   Universidade do Estado do Amazonas, Páscoa Marcio Leonel Farias Reis
Published: January 2021

A crescente produção de trabalhos acadêmicos, inclusive no Brasil, inspirados na teoria das schematae de Gjerdingen, em paralelo com a discussão no âmbito da teoria das tópicas musicais, a partir das ideias de Ratner, vem estimulando a busca de significados resultantes da interação entre aspectos sintáticos e semânticos da obra musical, especialmente aquela desenvolvida entre os séculos XVIII e XIX. Tais trabalhos, reunidos a partir da junção da musicologia com vários outros campos de estudo, na música ou fora dela, reacendem o debate sobre o uso da Retórica e da Poética como orientação dos projetos composicionais dos autores daquele período. Neste sentido, o presente artigo discute as estratégias criativas de André da Silva Gomes (1752-1844) à luz da sua Arte explicada do Contraponto.
Textos, canções e sons no Brasil pós-1964: o Grupo de Teatro Opinião em cena
Authors:   Universidade do Estado de Santa Catarina (UDESC), Florianópolis, SC., Paranhos Kátia Rodrigues
Published: January 2021

Este texto aborda a importância histórica do Grupo de Teatro Opinião (1965-1980) e dos seus espetáculos como expressão política de resistência à ditadura militar no Brasil. Na esteira disso, focalizo de que forma a utilização do discurso musical afeta o espectador não só por meio dos parâmetros sonoros, mas igualmente pela sua capacidade de sugerir imagens e de inventar espaços e lugares ao criar figurações cênico-dramáticas. Enfatizo, como características fundamentais desse teatro musicado, a mistura de tradições culturais e a produção/criação artística dos atores/cantores. Daí a pertinência da discussão sobre o contraponto entre as linguagens musicais e plásticas na composição da polifonia intrínseca ao espetáculo teatral.
Entrevista com Hercules Gomes
Authors:   Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP, Marques André Repizo
Published: January 2021

Entrevista com o pianista brasileiro Hercules Gomes. A presente entrevista contribuiu imensamente para a pesquisa acadêmica de mestrado (concluída dia 26 de junho de 2017) do entrevistador, que tem por propósito investigar a diversidade de interpretações da obra de Ernesto Nazareth, cuja performance tem sido realizada tanto por pianistas eruditos como por rodas de choro.
Drawing Subcubic 1-Planar Graphs with Few Bends, Few Slopes, and Large Angles
Authors: Kindermann Philipp , Montecchiani Fabrizio , Schlipf Lena , Schulz André
Published: January 2021

We show that the $1$-planar slope number of $3$-connected cubic $1$-planar graphs is at most four when edges are drawn as polygonal curves with at most one bend each, that is, any such graph admits a drawing with at most one bend per edge and such that the number of distinct slopes used by the edge segments is at most four.
This bound is obtained by drawings whose angular and crossing resolution is at least $\pi/4$.
On the other hand, if the embedding is fixed, then there is a $3$-connected cubic $1$-planar graph
that needs three slopes when drawn with at most one bend per edge.
We also show that two slopes always suffice for $1$-planar drawings of subcubic $1$-planar graphs with at most two bends per edge. This bound is obtained with angular resolution $\pi/2$ and the drawing has crossing resolution $\pi/2$ (i.e., it is a RAC drawing). Finally, we prove lower bounds for the slope number of straight-line $1$-planar drawings in terms of
number of vertices and maximum degree.
Two Results on Layered Pathwidth and Linear Layouts
Authors: Dujmović Vida , Morin Pat , Yelle Céline
Published: January 2021

Layered pathwidth is a new graph parameter studied by Bannister et al. (2015). In this paper we present two new results relating layered pathwidth to two types of linear layouts. Our first result shows that, for any graph $G$, the stack number of $G$ is at most four times the layered pathwidth of $G$. Our second result shows that any graph $G$ with track number at most three has layered pathwidth at most four. The first result complements a result of Dujmović and Frati (2018) relating layered treewidth and stack number. The second result solves an open problem posed by Bannister et al. (2015).
Transformation of the Peasant Family Life Cycle in the Middle Urals in Demographical Transition Circumstances
Authors: Mazur Liudmila Nikolaevna , Brodskaya Larisa Igorevna
Published: January 2021

The article examines the transformation of the life cycle of a peasant family in Russia in the 20th century in demographical transition circumstances aggravated by multiple demographical catastrophes. The information basis of the study is databases formed during the analysis of budget surveys of peasant farms in the Middle Urals in 1928/1929 and 1963. Supplemented by information from other sources (materials from the population censuses of 1926, 1939 and 1959), these data allowed the authors to compare the family structure of the rural population of the Urals in the 1920s and the 1960s (the initial and the final stage of the demographical transition) and characterize its dynamics (the life cycle). Whereas in a traditional society the life cycle of a peasant family was largely determined by the dynamics of the peasant economy development, the urbanized society witnesses two standards of the family (two-parent/single parent one) with the corresponding types of the life cycle: the nuclear family (the reference version) and the incomplete family (the reduced version). The consequences of the Soviet modernization contributed to the transformation of fragmented forms of the family into a typical variant of the family landscape not only in urban but also in rural areas. Modeling and analysis of the peasant family life cycle at the micro level made it possible to identify the mechanisms of the peasant family adaptation to external and internal challenges that are characteristic of different stages of the demographic transition.
Effect of interface modification on performances of organic-inorganic hybrid perovskite solar cells
Authors: Ji Chao , Liang Chun-Jun , You Fang-Tian , He Zhi-Qun ,   Key Laboratory of Luminescence and Optical Information, Ministry of Education, School of Science, Beijing Jiaotong University, Beijing 100044, China
Published: January 2021

As one of the most dazzling star materials in recent years, perovskite has attracted extensive attention due to its unique photoelectric properties. Since the first report on 3.8% power conversion efficiency of perovskite solar cells (PSCs) was published in 2009, its efficiency has increased to 25.2% in a short period of 10 years, almost comparable to the efficiency of commercial polysilicon cells. However, due to its simple preparation process, it is easy to introduce a large number of defects in the film formation process. The defects accelerate the recombination of carriers and thus hindering the carrier transport channel, which is unfavorable for the preparation of high efficiency perovskite solar cells. Moreover, the existence of defects will affect the stability of PSCs, accelerate the degradation of materials, thereby hindering its further commercial development. Therefore, it is very important to understand the mechanism of defects and effectively suppress the generation of defects for the fabrication of high performance devices. As an effective passivation strategy, the interface modification has been widely used. In this paper, the locations of defects in different structures of devices and their effects on device performance are discussed. Based on the carrier transport layer passivation strategy and perovskite interface modification strategy, the mechanism of the passivation defects at the transport layer/perovskite interface is analyzed. The great advantages of passivation strategy and the classification of appropriate passivation materials are pointed out. It is hoped that this paper can provide useful guidance for developing the perovskite solar cells with high repeatability, high efficiency and long-term stability.
Reversine, a selective MPS1 inhibitor, induced autophagic cell death via diminished glucose uptake and ATP production in cholangiocarcinoma cells
Authors: Prajumwongs Piya , Waenphimai Orawan , Vaeteewoottacharn Kulthida , Wongkham Sopit , Sawanyawisuth Kanlayanee
Published: January 2021

Reversine is a selective inhibitor of mitotic kinase monopolar spindle 1 (MPS1) and has been reported as an anticancer agent in various cancers. The effects of reversine on bile duct cancer, cholangiocarcinoma (CCA), a lethal cancer in Northeastern Thailand, were investigated. This study reports that reversine inhibited cell proliferation of CCA cell lines in dose- and time-dependent manners but had less inhibitory effect on an immortalized cholangiocyte cell line. Reversine also triggered apoptotic cell death by decreasing anti-apoptotic proteins, Bcl-XL and Mcl-1, increasing Bax pro-apoptotic protein and activating caspase-3 activity. Moreover, reversine induced autophagic cell death by increasing LC3-II and Beclin 1 while decreasing p62. Reversine activated autophagy via the AKT signaling pathway. Additionally, this study demonstrated for the first time that reversine could diminish the expression of Hypoxia-Inducible Factor 1- alpha (HIF-1α) and glucose transporter 1 (GLUT1), resulting in a reduction of glucose uptake and energy production in CCA cell lines. These findings suggest that reversine could be a good candidate as an alternative or supplementary drug for CCA treatment.
Differential relieving effects of shikonin and its derivatives on inflammation and mucosal barrier damage caused by ulcerative colitis
Authors: Han Hongwei , Sun Wenxue , Feng Lu , Wen Zhongling , Yang Minkai , Ma Yingying , Fu Jiangyan , Ma Xiaopeng , Xu Xinhong , Wang Zhaoyue , Yin Tongming , Wang Xiao-Ming , Lu Gui-Hua , Qi Jin-Liang , Lin Hongyan , Yang Yonghua
Published: January 2021

Background

Ulcerative colitis (UC) is one of the most challenging human diseases. Natural shikonin (SK) and its derivatives (with have higher accumulation) isolated from the root of Lithospermum erythrorhizon have numerous beneficial effects, such as wound healing and anti-inflammatory activities. Some researchers have reported that hydroxynaphthoquinone mixture (HM) and SK attenuate the acute UC induced by dextran sulfate sodium (DSS). However, no existing study has systemically investigated the effectiveness of SK and other hydroxynaphthoquinone natural derivative monomers on UC.

Methods

In this study, mice were treated with SK and its derivatives (25 mg/kg) and mesalazine (200 mg/kg) after DSS administration daily for one week. Disease progression was monitored daily by observing the changes in clinical signs and body weight.

Results

Intragastric administration natural single naphthoquinone attenuated the malignant symptoms induced by DSS. SK or its derivatives remarkably suppressed the serum levels of pro-inflammatory cytokines while increasing the inflammatory cytokine interleukin (IL)-10 . Additionally, both SK and alkanin restrained the activities of cyclooxygenase-2 (COX-2), myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) in serum and colonic tissues. SK and its derivatives inhibited the activation of nucleotide binding oligomerization domain-like receptors (NLRP3) inflammasome and NF-κB signaling pathway, thereby relieving the DSS-induced disruption of epithelial tight junction (TJ) in colonic tissues.

Conclusions

Our findings shed more lights on the pharmacological efficacy of SK and its derivatives in UC against inflammation and mucosal barrier damage.
High efficient separation of olefin from fluid catalytic cracking naphtha: Separation mechanism and universal simulation method
Authors: Zhang Yuhao , Zhao Liang , Chen Feng , Wang Yongtao , Gao Jinsen , Cao Liyuan , Wang Hui , Xu Chunming
Published: January 2021

The fluid catalytic cracking (FCC) naphtha critical component‐oriented separation process is an efficient method to produce ultra‐low‐sulfur (<10 μg/g) gasoline with minimal loss of octane number (<1 RON). However, the product quality is highly dependent on the structure of the components of FCC naphtha. Aromatics and thiophene sulfides without a methyl side chain favor the separation of olefin. The major impulse of olefin separation is the solvent‐induced dipole of aromatics or thiophene sulfides, leading to a “Plane‐to‐Plane” combination between the solvent and aromatics or thiophene sulfides, accompanied by a steric hindrance due to their side chains. This condition resulted in 2–3 times greater θ of benzene and thiophene compared with that of toluene and 3‐methylthiophene. In addition, an improved non‐random two‐liquid model was proposed based on the above results, and a simulation method for FCC naphtha solvent extraction process was established. The calculation results accorded well with industry data.
Candidate pharmacological treatments for substance use disorder and suicide identified by gene co‐expression network‐based drug repositioning
Authors: Cabrera‐Mendoza Brenda , Martínez‐Magaña José Jaime , Monroy‐Jaramillo Nancy , Genis‐Mendoza Alma Delia , Fresno Cristóbal , Fries Gabriel Rodrigo , Walss‐Bass Consuelo , López Armenta Mauro , García‐Dolores Fernando , Díaz‐Otañez Carlos Enrique , Flores Gonzalo , Vázquez‐Roque Rubén Antonio , Nicolini Humberto
Published: January 2021

Patients with substance use disorders (SUD) are at high risk to die by suicide. So far, the neurobiology of the suicide‐SUD association has not been elucidated. This study aimed to identify potential pharmacological targets among hub genes from brain gene co‐expression networks of individuals with SUD in a suicidal and non‐suicidal context. Post‐mortem samples from the prefrontal cortex of 79 individuals were analyzed. Individuals were classified into the following groups: suicides with SUD (n = 28), suicides without SUD (n = 23), nonsuicides with SUD (n = 9), nonsuicides without SUD (n = 19). Gene expression profiles were evaluated with the Illumina HumanHT‐12 v4 array. Co‐expression networks were constructed in WGCNA using the differentially expressed genes found in the comparisons: (a) suicides with and without SUD and (b) nonsuicides with and without SUD. Hub genes were selected for drug‐gene interaction testing in the DGIdb database. Among drugs interacting with hub genes in suicides we found MAOA inhibitors and dextromethorphan. In the nonsuicide individuals, we found interactions with eglumegad and antipsychotics (olanzapine, clozapine, loxapine). Modafinil was found to interact with genes in both suicides and nonsuicides. These drugs represent possible candidate treatments for patients with SUD with and without suicidal behavior and their study in each context is encouraged.
New Pd‐phosphorus ylide complexes based on FC60 as heterogeneous nano‐catalyst for H/D exchange reaction
Authors: Yousefi Abed , Sabounchei Seyyed Javad , Hashemi Ali
Published: January 2021

In this account, new Pd(0) complexes of phosphorus ylides based on fullerene C60 (FC60) were synthesized and utilized as the first fullerene‐based heterogeneous nano‐catalysts for H/D exchange reaction. Four new palladacyclopropa‐[60]fullerene complexes 1–4, [(η2‐C60)Pd(Y1–4)2] (Y1 = PPh3CHC(O)C6H4‐p‐NO2, Y2 = PPh3CHC(O)C6H4‐p‐CH3, Y3 = (p‐tolyl)3P‐CHC(O)C6H4‐p‐NO2, and Y4 = (p‐tolyl)3P‐CHC(O)C6H4‐p‐CH3), were prepared through dissolving the related α‐keto stabilized phosphorus ylide in toluene solution in the presence of FC60 and Pd (dba)2 (dba = dibenzylideneacetone). All of the complexes were characterized using Nuclear magnetic resonance (NMR) (1H, 13C, and 31P), Infrared spectroscopy (IR), Ultraviolet‐visible spectroscopy (UV‐visible), fluorescence, Electrospray Ionisation Mass Spectrometry (ESI‐MS), and Energy‐dispersive X‐ray spectroscopy (EDX) spectroscopies, and scanning electron microscopy (SEM) and TEM techniques. The data proved that FC60 and two ylides were coordinated to Pd(0) center through two hexagons and two ylidic carbon atoms, respectively. An evaluation was also performed to compare the catalytic activity of synthesized Pd complex 1 and a conventional heterogeneous catalyst, 10% Pd on carbon, in H/D exchange reaction. The results indicate that the process of H/D exchange reaction in aromatic rings of benzoic acid derivatives progressed more efficiently by Pd complex 1.
Deep Eutectic Solvent‐Induced Polyacrylonitrile‐Derived Hierarchical Porous Carbon for Zinc‐Ion Hybrid Supercapacitors
Authors: Chen Chaojie , Li Zhiwei , Xu Yinghong , Liao Haojie , Wu Langyuan , Dou Hui , Zhang Xiaogang
Published: January 2021

Hierarchical porous carbon that possesses large surface area and high porosity has become an important electrode material for supercapacitors. However, some unavoidable issues like complex approach and environmental pollution involved in traditional chemical activation restrict the sustainable development of carbons. Herein, a green, low‐cost, and safe urea‐zinc chloride deep eutectic solvent (DES) is proposed to prepare polyacrylonitrile derived three‐dimensional carbon nanosphere (D‐PC). Specially, the D‐PC efficiently accelerates electrolyte ions migration and enhances charge storage due to its interconnected ionic pathways and large accessible active surfaces. When employing the D‐PC as positive electrode of zinc‐ion hybrid supercapacitors, a high specific capacitance of 261.5 F g−1 at 0.2 A g−1 along with a cycling stability of 91.3 % after 10000 cycles at 5 A g−1. Meanwhile, such device holds the maximum energy/power density of 93.9 Wh kg−1/16.7 kW kg−1 at 0.2 A g−1/20 A g−1, respectively. Thanks to the unique physicochemical properties of as‐obtained D‐PC, an ultrahigh areal capacitance of 2.2 F cm−2 also can be achieved at a mass loading of 23 mg cm−2. The satisfying structure and performance highlight the potential of DESs in the design of functional carbons.
The influence of catalyst flow rate and superficial gas velocity on the modified two‐phase model for propylene polymerization in a gas‐phase fluidized bed reactor
Authors: Atan Mohd Farid , Hussain Mohd Azlan , Shamiri Ahmad
Published: January 2021

Olefin polymerization, especially of propylene in gas‐phase fluidized bed reactors, is increasingly prevalent because of its ability to handle the continuous process, among other advantages. The challenge for modelling this process is solving the high nonlinearity phenomena in such a system. This research studies the influence of catalyst flow rate and superficial gas velocity on the modified two‐phase model. The catalyst flow rates were set at 1 × 10−4, 2 × 10−4, and 3 × 10−4 kg/s, while the superficial flow rates were set at 0.35, 0.5, and 0.65 m/s. Production rate, reactor temperature, and heat‐loss flow rate were found to be proportional to catalyst flow rate and inversely proportional to superficial gas velocity. Heat loss through the fluidized bed wall had an influence only on the reactor temperature. Finally, predicted reactor temperatures corresponded closely to the pilot plant data, with deviations smaller than 0.5%.
A novel FCNs‐ConvLSTM network for video salient object detection
Authors: Huang Hai , Liu Chang , Tian Lei , Mu Junsheng , Jing Xiaojun
Published: January 2021

A video saliency detection model is proposed based on deep learning, which improves the existing fully convolutional network (FCN)‐based model by introducing a convolutional long short‐term memory (ConvLSTM) module. The ConvLSTM splits the input into two flows with two layers in each one. The two flows have different dilation rates that make them have different receptive fields, which enables the proposed model to perform better in depicting the contour of objects. The ConvLSTM module receive frames in order as input rather than unordered frames that FCN modules do, so the proposed model can learn both spatial and temporal information of video data. Considering the lack of manually labeled annotations in the dataset, augmentation technologies are used in training the model to expand the dataset, such as performing mirror transformation, introducing Gaussian noise and abandoning every other frame to simulate fast movement situation. The proposed FCNs‐ConvLSTM model is trained and evaluated on extensively used dataset, and the results demonstrate that it performs better on recall rate (0.52 to 0.64) with a similar level on precision rate (0.72) when threshold is 125 and it also gets an increase on maximum F‐measure (0.66 to 0.70), which indicates that the proposed model has better capacity in detecting moving object.
Step‐ahead spot price densities using daily synchronously reported prices and wind forecasts
Authors: Solibakke Per B.
Published: January 2021

This paper uses non‐linear methodologies to follow the synchronously reported relationship between the Nordic/Baltic electric daily spot auction prices and geographical relevant wind forecasts in MWh from early 2013 to 2020. It is a well‐known market (auctions) microstructure fact that the daily wind forecasts are information available to the market before the daily auction bid deadline at 11 a.m. The main objective is therefore to establish conditional and marginal step ahead spot price density forecast using a stochastic representation of the lagged, synchronously reported and stationary spot price and wind forecast movements. Using an upward expansion path applying the Schwarz (Bayesian information criterion [BIC]) criterion and a battery of residual test statistics, an optimal maximum likelihood process density is suggested. The optimal specification reports a significant negative covariance between the daily price and wind forecast movements. Conditional on bivariate lags from theSNPinformation and using the known market information for wind forecast movements att1, the paper establishes one‐step‐ahead bivariate and marginal day‐ahead spot price movement densities. The result shows that wind forecasts significantly influence the synchronously reported spot price densities (means and volatilities). The paper reports day‐ahead bivariate and marginal densities for spot price movements conditional on several very plausible price and wind forecast movements. The paper suggests day‐ahead spot price predictions from conditional and synchronously reported wind forecasts movements. The information should increase market participants spot market insight and consequently make spot price predictions more accurate and the confidence interval considerably narrower.
Nicorandil mitigates folic acid‐induced nephrotoxicity in mice: Role of iNOS and eNOS
Authors: Ezzat Dalia M. , Soliman Asmaa M. , El‐Kashef Dalia H.
Published: January 2021

Folic acid (FA)‐induced acute kidney injury (AKI) is a commonly used model in experimental animals for studying renal injury. This study aimed to investigate the probable protecting impact of nicorandil against FA‐induced renal dysfunction. A mouse model was executed by a single injection of FA (250 mg/kg). Nicorandil was orally administrated in two doses (50 and 100 mg/kg) for 10 days. Nicorandil repressed the progression of FA‐induced AKI as evidenced by the improvement of histopathological alterations and the substantial decrease of serum levels of creatinine, urea, blood urea nitrogen, malondialdehyde (MDA), and urinary protein levels. Moreover, nicorandil resulted in a profound reduction in oxidative stress as manifested by decreased MDA and increased reduced glutathione and superoxide dismutase in renal tissue. Notably, nicorandil suppressed FA‐induced inflammation; it reduced renal levels of nuclear factor‐κB, tumor necrosis factor‐α, and interleukin‐6. Furthermore, nicorandil decreased renal levels of nitric oxide, inducible nitric oxide synthase, and increased endothelial nitric oxide synthase. Lastly, nicorandil efficiently decreased expression of the proapoptotic protein (Bax) and caspase 3. Nicorandil confers dose‐dependent protection against FA‐induced AKI by alleviating oxidative stress, inflammation besides modulating nitric oxide synthase and reducing apoptosis.
Dynamics of Top‐Down Control and Motor Networks in Parkinson's Disease
Authors: Chen Li , Bedard Patrick , Hallett Mark , Horovitz Silvina G.
Published: January 2021

Background

Motor symptoms in Parkinson's disease (PD) patients might be related to high‐level task‐control deficits. We aimed at investigating the dynamics between sensorimotor network and top‐down control networks (frontal–parietal, cingulo‐opercular, and cerebellar) in PD and at determining the effects of levodopa on the dynamics of these networks.

Methods

We investigated dynamic functional connectivity (dFC), during resting state functional magnetic resonance imaging, between sensorimotor network and top‐down control networks in 36 PD patients (OFF medication, PD‐OFF) and 36 healthy volunteers. We further assessed the effect of medication on dFC in18 PD patients who were also scanned ON medication.

Results

The dFC analyses identified three discrete states: State I (35.68%) characterized by connections between the cerebellum and sensorimotor network, State II (34.17%) with connections between the sensorimotor and frontal–parietal network, and State III (30.15%) with connection between the sensorimotor and cingulo‐opercular network. PD patients have significantly fewer occurrences and overall spent less time (shorter dwell time) in State II compared to healthy controls. After levodopa intake, dwell time improved toward normal. The change in dwell time before and after taking levodopa was negatively related to the respective changes in Unified Parkinson's Disease Rating Scale, Part III. PD‐OFF showed significantly decreased connectivity between sensorimotor and control networks and increased connectivity within control networks. These changes were partially improved after levodopa intake.

Conclusions

Dopamine depletion in PD is associated with abnormalities in temporal and spatial properties between cognitive control and sensorimotor network, possibly contributing to clinical deficits. Levodopa partially restores the network function toward the values observed in healthy volunteers. © 2021 International Parkinson and Movement Disorder Society
Two tSNPs in BRIP1 are associated with breast cancer during TDT analysis
Authors: Li Xuefei , Li Zhuo , Yang Miao , Luo Yan , Hu Li , Xiao Zhi , Huang Aji , Huang Juan
Published: January 2021

Objectives

This study aimed to investigate and confirm the association between 15 single nucleotide polymorphisms of four susceptibility genes (NBS1, TP53, PTEN, and BRIP1) and the susceptibility of breast cancer.

Methods

The genome DNA was extracted from peripheral blood and tumor tissues from one hundred and seventeen core families. 15 SNPs were detected by PCR. The transmission disequilibrium test (TDT) and the Hardy–Weinberg equilibrium (HWE) are used to verify the association between these SNPs and breast cancer. Further correlation between SNPs and certain pathological features of the tumor, including tumor size, location of lymph nodes, pathologic classification, and the stage and subtype of breast cancer, are analyzed by the chi‐square test and logistic regression analysis.

Results

Based on TDTs, two SNPs of rs7220719 and rs11871753 in BRIP1 showed a significant association with breast cancer, while the other 13 selected SNPs did not. However, further statistical analysis demonstrated no obvious differentiation in the clinical characteristics of breast cancer between 37 patients with rs7220719 and 80 patients with wild types. Similar results were also found for rs11871753.

Conclusions

The data provided the evidence for the association between two SNPs of BRIP1 and breast cancer, but did not affect certain clinical phenotypes.
Fast T1 measurement of cortical bone using 3D UTE actual flip angle imaging and single‐TR acquisition (3D UTE‐AFI‐STR)
Authors: Wei Zhao , Jang Hyungseok , Bydder Graeme M. , Yang Wenhui , Ma Ya‐Jun
Published: January 2021

Purpose

To describe a new method for accurate T1 measurement of cortical bone that fits the data sets of both 3D UTE actual flip angle imaging (UTE‐AFI) and UTE with a single TR (UTE‐STR) simultaneously (UTE‐AFI‐STR).

Theory and Methods

To make both the constant values and longitudinal mapping functions in the signal equations for UTE‐AFI and UTE‐STR identical, the same RF pulses and flip angles were used. Therefore, there were three unknowns in the three equations. This was sufficient to fit the data. Numerical simulation as well as ex vivo and in vivo cortical bone studies were performed to validate the T1 measurement accuracy with the UTE‐AFI‐STR method. The original UTE‐AFI variable TR (VTR) (ie, combined UTE‐AFI and UTE with VTR) and simultaneous fitting (sf) of UTE‐AFI and UTE‐VTR (sf‐UTE‐AFI‐VTR) methods were performed for comparison.

Results

The numerical simulation study showed that the UTE‐AFI‐STR method provided accurate value of T1 when the SNR of the UTE‐STR image was higher than 40. The ex vivo study showed that the UTE‐AFI‐STR method measured the T1 of cortical bone accurately, with difference ratios ranging from −5.0% to 0.4%. The in vivo study showed a mean T1 of 246 ms with the UTE‐AFI‐STR method, and mean difference ratios of 2.4% and 5.0%, respectively, compared with the other two methods.

Conclusion

The 3D UTE‐AFI‐STR method provides accurate mapping of the T1 of cortical bone with improved time efficiency compared with the UTE‐AFI‐VTR/sf‐UTE‐AFI‐VTR methods.
Pass‐Through effect of monetary policy tools on economic growth in Nigeria
Authors: Sule Abubakar
Published: January 2021

This study seeks to examine the pass‐through effect of monetary policy tools on economic growth in Nigeria using quarterly time series data from Q12008 to Q42018. The study employed Augmented Dickey Fuller's unit root test, lag selection criteria, and impulse response function under Toda‐Yamamoto approach to examine the pass‐through effect of monetary policy tools on economic growth. The summary of the results is that, the dynamism in monetary policy tools through money supply remains inconsistent and the changes (either increase/decrease) in these elements could dampen down availability of credit to core private sectors thus hampering growth and development. This study therefore recommends; that monetary authority takes proactive measures to ensure sound and robust commercial banks that can facilitates substantial funds to core private sector to boost productivity of the economy. This can be achieve through close monitoring of banks and ensuring full implementations of indirect monetary policy tools.
Topological embeddings into random 2‐complexes
Authors: Farber Michael , Nowik Tahl
Published: January 2021

We consider 2‐dimensional random simplicial complexes Y in the multiparameter model. We establish the multiparameter threshold for the property that every 2‐dimensional simplicial complex S admits a topological embedding into Y asymptotically almost surely. Namely, if in the procedure of the multiparameter model on n vertices, each i‐dimensional simplex is taken with probability pi = pi(n), then the threshold is . Our claim in one direction is in fact slightly stronger, namely, we show that if is sufficiently larger than then every S has a fixed subdivision S′ which admits a simplicial embedding into Y asymptotically almost surely. In the other direction we show that if is sufficiently smaller than , then asymptotically almost surely, the torus does not admit a topological embedding into Y.
An efficient load balancing using seven stone game optimization in cloud computing
Authors: Karthikeyan Periyasami
Published: January 2021

Cloud computing offers massive processing power to cloud client to solve the scientific, financial forecasting, and weather forecasting applications. The process of distributing to the load to the different cloud service providers is a complex problem. Cloud service providers have different types of virtual machines with different computing power types in multi‐layered architectures. Various optimization works have been proposed to tackle the load balancing problem in cloud service providers. Improving performance in load balancing is a cumbersome task. Seven stone game optimization (SSGO) is designed based on the south Indian seven stone game workflow. The proposed method's foremost ambition is to reduce makespan time and maximize cloud service providers' utilization. The proposed method was simulated, and results demonstrate that minimizes the makespan time and maximizes the resource utilization than the particle swarm optimization (PSO), genetic algorithm (GA), simulated annealing (SA), and Tabu search (TS). The experimental results show that the SSGO provides 4% more resource utilization than PSO, 5% more than GA, and 7% more than SA and 10% more than TS.
Juvenile Chinook Salmon Survival, Travel Time, and Floodplain Use Relative to Riverine Channels in the Sacramento–San Joaquin River Delta
Authors: Pope Adam C. , Perry Russell W. , Harvey Brett N. , Hance Dalton J. , Hansel Hal C.
Published: January 2021

Floodplains provide multiple benefits to both resident and migratory fish species, including juvenile Chinook Salmon Oncorhynchus tshawytscha, but direct comparisons of survival during migration through a floodplain versus riverine routes are scarce. The Yolo Bypass is a broad floodplain of the Sacramento River that floods in about 30% of years in response to large, uncontrolled runoff events. We analyzed data from an acoustic telemetry study conducted in winter 2016 to estimate the proportion of tagged juvenile Chinook Salmon entrained from the Sacramento River into the Yolo Bypass and their spatial distribution within the Yolo Bypass. In addition, we compared survival and travel time of Chinook Salmon that migrated through the Yolo Bypass to those migrating via alternative non‐floodplain migration routes at varying stages of a flood event that activated the Yolo Bypass. We found that entrainment into the Yolo Bypass ranged from 1% to 80% among different release groups, with the highest entrainment coinciding with the peak of the March 2016 flooding event. Survival for Chinook Salmon migrating through the Yolo Bypass was similar to survival of those migrating through main‐stem migration routes. At the relatively high flows necessary to enable flooding of the Yolo Bypass, survival estimates varied little among release groups and migration routes. Furthermore, mean daily survival rates for Chinook Salmon migrating through the flooded Yolo Bypass were comparable to those of fish migrating through the other non‐floodplain routes. Median travel times remained relatively constant during various stages of flooding in the Yolo Bypass. This research should help managers to better understand the potential costs and benefits to floodplain restoration and routing of migrating Chinook Salmon into off‐channel habitat.