bluuebunny/crossref_metadata_2025 huggingface dataset:
Using Calculators to Stimulate Conjectures and Algebraic Proofs
Authors: Olson Melfried
Published: January 2021

Much has been written about the uses of calculators and the resulting impact on computational skills, but the calculator can also be used in problems where determining patterns and making conjectures are stressed. In these activities, the calculator can enable students to test more difficult cases that would have been fruitless, if not impossible, without the calculator.
Competency Identification and Assessment in Mathematics Teacher Education: Some Issues
Authors: Farrell Margaret A.
Published: January 2021

Some good suggestions on how a competency-based teacher-education program might focus on nontrivial tasks and measure them in ways that are not merely based on checklists.
Improving Student Attitudes Through A Mathematics Miniconference
Authors: Gordon Jeffry , Gordon Berchie
Published: January 2021

The National Council of Teachers of Mathematics and its affiliated organizations expend considerable effort organizing and conducting professional conferences. These programs generally contain a variety of activities designed for classroom teachers. If you have ever been to one, you have no doubt felt the enthusiasm of the speaker and maybe you went away from the conference all “fired up” and eager to go back and teach. Many of your colleagues have often felt the same way. This generated enthusiasm is often a major strength of the conference.
Try a Complement
Authors: Archer J. Andrew
Published: January 2021

A chance for some unusual drill has more generality than expected.
A Summer Course with the TI 57 Programmable Calculator
Authors: Maor Eli
Published: January 2021

Let me wish that the calculating machine, in view of its great importance, may become known in wider circles than is now the case. Above all. every teacher of mathematics should become familiar with it. and it ought to be possible to have it demonstrated in secondary instruction.
To Read Or Not to Read, That is the Question!
Authors: Krulik Stephen
Published: January 2021

Use these ideas to help your students sharpen their ability to read mathematics.
Nick's First Theorem
Authors: Lieske Phillip F. , Faillace Nicholas J.
Published: January 2021

A human interest account of a discovery of a mathematical formula.
Posing and Solving Verbal Problems
Authors: Bell Frederick H.
Published: January 2021

Anyone who has taught the textbook sections on verbal problems in an algebra course knows that students have trouble solving these problems. Consequently, there is a tendency to change solving verbal problems into doing exercises by giving students algorithms for each of the standard types of problems in textbooks. Since textbook verbal problems are difficult for students and atypical of real-world applications of mathematics, why do teachers bother with them?
Applications: Light My Fire
Authors: Knill George , Fawceti George
Published: January 2021

Everyone knows that wood bums at a very high temperature. This burning is a chemical process that combines oxygen and carbon. The process occurs at very low temperatures as well as at very high ones. At high temperatures the process is spectacular-fire. At low temperatures (room temperature) you won’t even notice it, although it is still going on. Wood is always burning.
Is Your Mind In A Rut?
Authors: Allinger Glenn D.
Published: January 2021

Fill in the blank, please. “Baseball, hot dogs, apple pie, and ____” A red light, as a traffic signal, means____ The number of distinct triangles pictured in figure 1 is ____.
A Generalization Of The Fibonacci Formulae
Authors: Kelly Lucille A.
Published: January 2021

Students are surprised by the magic within the Fibonacci numbers, and they find that with some experimentation they can discover some of this magic. The following generalization arose from a discussion in a liberal arts mathematics class that had been learning about patterns in sets of numbers such as the counting numbers, even numbers, odd numbers, and the square and triangular numbers and finally forming recursive sequences by creating recursive formulae.
Determinants, Diagonals, And Discovery
Authors: Murty Vedula N. , Swetz Frank J.
Published: January 2021

Determinants are frequently taught in advanced algebra classes and survey courses in college mathematics as a tool for solving systems of simultaneous linear equations.
I Can See Clearly Now” (Another Look At Norman Windows)
Authors: Gibson Edwin C. , Gibson Jane B.
Published: January 2021

… Small lights of those who meditate at midnight And lights directed through the coloured panes of windows… —T. S. Eliot Choruses from "The Rock"
All Triangles For Which sin⁡Aa Is a Constant
Authors: Siegel Steven L.
Published: January 2021

Solving the following problem, suggested by the law of sines, provides several exciting and satisfying moments of insight:

What is the equivalence class of triangles for which (sin A)/a is a constant i
Activities: The Rhombus Construction Company
Authors: Troccolo Joseph A.
Published: January 2021

This section is designed to provide mathematical activities suitable for reproduction in worksheet and transparency form for classroom use. This material may be photoreproduced by classroom teachers for use in their own classes without requesting permission from the National Council of Teachers of Mathematics. Laboratory experiences, discovery activities, and model constructions drawn from the topics of seventh, eighth, and ninth grades are most welcome for review.
Nearly Isosceles Pythagorean Triples
Authors: Ryden Robert
Published: January 2021

With the high school mathematics curriculum as full as it is, why should we busy teachers take class time away from the syllabus to investigate patterns of no discernible practical value? My answer is that students should be made aware that there is more to mathematics than learning how to solve an endless variety of problems. There is a beauty in its patterns, and especially for those who may not pursue mathematics beyond high school, these patterns may be the only mathematics they will remember. Recently in my geometry class we discovered a pattern in Pythagorean triples that, in addition to being interesting in itself, can be used at various levels to illustrate inductive reasoning, proof by mathematical induction, and other algebraic proofs. It can also generate several different computer programs.
Apportionment Examples: An Application of Decimal Ordering
Authors: Litwiller Bonnie H. , Duncan David R.
Published: January 2021

In the January 1982 Mathematics Teacher, Sullivan described several methods of apportioning seats in the United States House of Representatives. He made a strong case for the Hamilton method of apportioning House seats to the states as compared to the currently used equal proportions method.
Round Robin Schedules
Authors: Iannone Michael A.
Published: January 2021

As a tennis enthusiast. I was asked to create a schedule that insured that each team in a league would play one match against every other team in the league. Such a schedule is generally referred to as a round robin schedule and is frequently used in a variety of competitions. After beginning the task using a random approach, which proved unproductive, I researched the problem and found that such schedules are a simple application of congruence (Ore 1967) and lend themselves nicely to a computer solution.
There is Something Odd About Cubics
Authors: Smith Betsy Darken
Published: January 2021

Which of the graphs in figure I do you think are graphs of cubic functions?
Characteristics and Special Needs of the Gifted Student in Mathematics
Authors: Heid M. Kathleen
Published: January 2021

A cautious return to public concern for the education of gifted and talented youth has been evident in recent years. Although the latter half of the seventies produced an increase in funding, personnel, statutes, and policies concerned with the education of the gifted and talented, financial support of programs still falls considerably short of meeting the needs of these young people (Mitchell and Erickson 1978, p. 15).
An Account of a Mathematician's Education
Authors: Fefferman Charles
Published: January 2021

As a child, I read everything I could find on “children's science”—dinosaurs, how rockets work, and so forth. I became dissatisfied with laymen's explanations and tried at age eight or nine to read a physics textbook. I couldn't understand a word, because it assumed a mathematical background. When I asked my parents for help, my father understood the problem and began to teach me basic mathematics.
Gregory Interpolation: A Trick for Problem Solvers from Out of the Past
Authors: Long Calvin T.
Published: January 2021

How to solve it—that's the question! And a very important question it is for today's teachers and students of mathematics. But problem solving has always been at the very heart of mathematics, and the successful student cannot have too many tricks up his or her sleeve to accomplish the task. Suppose you were confronted with any of the following three problems; how would you proceed?
SoundOFF: We Have A Choice
Authors: Maier Gene
Published: January 2021

The next dozen years can be the best of times or the worst of times for mathematics educators, depending on how we react to the revolution. I'm talking about the revolution that has already eradicated the slide rule, doomed trig tables, and to borrow a phrase from a president of the Mathematical Association of America, will leave paper-and-pencil long division “as dead as a dodo bird.” The world of mathematical computations will be revolutionized by electronic calculators and computers.
SoundOFF: Separate Computer Science from Mathematics
Authors: Rising Gerald R.
Published: January 2021

My text for this brief sermon is a comment made to me at luncheon several weeks ago by Heinrich Martins, director of the SUNY Buffalo computer center. “Several major research universities,” he said, “have found that their ratio of computer usage has moved to two to one, humanities to science.”
Applications: On Population and Resources
Authors: Schwartzman Steven
Published: January 2021

During the last few years many reports and articles have appeared on the starvation and overpopulation that is occurring in some parts of the world. How accurately have these subjects been represented, and how well does your intuition coincide with the facts? Before reading any further, take a few minutes to answer the preliminary questions in table 1.
Counting Using License Plates and Phone Numbers: A Familiar Experience
Authors: Landauer Edwin G.
Published: January 2021

Almost every introductory statistics course includes a section on probability that employs several counting rules. Students find the section one of the most difficult because it involves more mathematics than others. The use of examples involving familiar items, such as dice and cards, would seem to make the topic easier. It is surprising, however, to find that a high percentage of the students are not familiar with a standard deck of cards. Also, only a limited number of examples that involve dice are possible.
Why Are We Learning This?
Authors: Bedford Crayton W.
Published: January 2021

Why are we learning this?” Because this question has few answers, it has frustrated secondary school mathematics teachers for years. We are dissatisfied with vague references to future courses and former scientists, and we beg the question by invoking school requirements. Yet we continue to teach complex fractions and trigonometric formulas, believing our work important for our students. For those who become engineers and scientists the importance of such work is clear, but what about business persons, lawyers, secretaries, and teachers? How do we serve them?
The College Entrance Examination Board and Mathematics Education
Authors: Jones Chancey O. , Valentine John A.
Published: January 2021

The participation by secondary school and college teachers of computer science in the development of an Advanced Placement computer science course description and examination is a good example of the interaction between the world of the College Board and the world of mathematics. A long series of such interactions has occurred since the College Board was founded at the turn of the century; a look back at how the board was created and how it has evolved can help to explain the relationship between board activities and mathematics education today.
Microcomputer-assisted discoveries: Mean, Standard Deviation, and Stopping the Stars
Authors: Kimberling Clark
Published: January 2021

When students first meet the concepts of the mean and standard deviation of a set of numbers, they are told that the numbers are called data and that the two ways of measuring the data, called the mean (or average) and the standard deviation, are of great importance in the study of statistics and probability.
Microcomputer-assisted mathematics: Circles and Star Polygons
Authors: Kimberling Clark
Published: January 2021

Circles appear in almost every mathematics course, and so it is no surprise that graphics programs about circles can provide “something for everyone.” Two such programs are offered in this article, along with a discussion of their use by students in grades 6–12. Students who work with these programs can gain a familiarity with the xy-plane, the radii and centers of circles, and ellipses. More advanced students can learn much about parametric equations and the use of random numbers to produce random shapes.
Sharing teaching ideas
Authors: Brown Susan A. , Olson Steven , Faulkner J. Earl
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. See the masthead page for details on submitting manuscripts for review.
Microcomputer-assisted mathematics: Graph Many Functions, Part 1
Authors: Kimberling Clark
Published: January 2021

High-resolution graphics provides an excellent way for precalculus and calculus students to discover the properties of functions by graphing them.
Sharing teaching ideas
Authors: Drysdale Ron , Ross Joan , Billik Melvin
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. See the masthead page for details on submitting manuscripts for review.
Microcomputer-assisted mathematics: Graph Many Functions, Part 3
Authors: Kimberling Clark
Published: January 2021

This is the final portion of an article about ways students can use an Applesoft BASIC program, “Graph Many Functions.” The program is printed in the previous issue of the Mathematics Teacher. It is also available on disk; see the References at the end of the article.
Mathematical Induction and Pascal's Problem of the Points
Authors: Coughlin Mary , Kerwin Carolyn
Published: January 2021

Mathematical methods and theories often have their beginnings in pure speculation or in a significant human problem that requires a solution. Pascal's interest in the science of probability arose from a problem that may not have been significant but was all too human: how to divide the stakes in an interrupted game of chance if the players are of equal skill (Smith 1929, 546).
Sharing teaching ideas
Authors: Folio Catherine , Zucker Andrew A. , Lay Steven R.
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. See the masthead page for details on submitting manuscripts for review.
Logic for Algebra: New Logic for Old Geometry
Authors: Retzer Kenneth A.
Published: January 2021

Tradition is easy to justify, whereas innovation requires a carefully prepared rationale. When we are content with what we traditionally do in the mathematics curriculum, almost any traditional justification seems substantial.
British Eyes on American Mathematics
Authors: Lingard David , Johnson Sylvia , O'brien Thomas C.
Published: January 2021

During the summer of 1984, the Teachers’ Center Project of Southern Illinois University at Edwardsville (SIUE) sponsored three-week-long courses for teachers.
Microcomputer-Assisted Mathematics: Exploring Number Theory with a Microcomputer
Authors: Fischer Frederic
Published: January 2021

It is clear that the computer can take much of the drudgery out of many mathematical analyses. Problems involving large sets of data requiring sorting, ordering, and laborious calculations readily come to mind. The computer is designed to handle such problems quickly and accurately.
Soundoff: Master Teacher Certification
Authors: Willoughby Stephen S.
Published: January 2021

A documented shortage of certified teachers of mathematics exists in the United States today. Although the shortage of numbers is easily documented, the quality of our teachers is a far more serious issue. Several states have such low standards that a person can be newly certified to teach mathematics courses that are more advanced than any that the person has ever taken. In response to the shortage, some states and local school districts have lowered or ignored standards and encouraged people with insufficient preparation in pedagogy and content to teach mathematics.
Logo and the Closed-Path Theorem
Authors: Olson Alton T.
Published: January 2021

Mathematics teachers and educators are in agreement that additional geometric experiences are necessary if we are going to improve students' general level of knowledge in geometry. Though we usually think of geometric experiences taking place in the real world, that isn't necessarily a requirement. We can simulate geometric microworlds very well by using a microcomputer and appropriate software. This article describes a program written in Apple Logo that can be used to explore a number of such microworlds.
Geometric Constructions Using Hinged Mirrors
Authors: Robertson Jack M.
Published: January 2021

The debate over what geometry to teach has raged without resolution or respite for years, with nearly any position having its proponents and detractors. However, in all these exchanges I have yet to hear the suggestion that the teaching of geometric constructions be replaced by something better, for a number of possible reasons. Most of the constructions we teach are actually quite useful. They give the secondary school student, starved for a Piagetian concrete-operational experience, something tangible. The constructions offer an opportunity for problem solving if properly presented. Probably most significant, however, is the simple fact that they are inherently interesting, as an extensive literature on the problems attests.
Chomp—an Introduction to Definitions, Conjectures, and Theorems
Authors: Keeley Robert J.
Published: January 2021

The concept of mathematics as an organized system of carefully defined ideas and logical extensions is a difficult one for students to grasp. The game of Chomp provides an opportunity to explore this concept by building a system while playing a game and giving students a chance to look at some open questions.
Mathematics and Meteorology
Authors: Wood Eric F.
Published: January 2021

One of the ironies of teaching mathematics is that real-life problems, although interesting, are often too difficult to consider in a secondary school classroom. Consequently the problems that are used in texts are often somewhat contrived. While working at the local weather office, I came upon several applications of trigonometry that are both interesting and instructive for high school students. The problems require that some background knowledge be presented to the students, but often they will have at least heard about the ideas from the nightly weather forecasts on television. These ideas make an interesting discussion for both teacher and student.
Two Problems That Illustrate the Techniques of Computer Simulation
Authors: Chance Joseph E. , Brazier Pearl W.
Published: January 2021

Most introductory courses in computing include a discussion or illustration of the technique of simulation (Gear 1978, 55-59; Pohl and Shaw 1981. 235-362). Problems involving simulation illustrate the enormous computational abilities of even a microcomputer and, more important, allow the student to observe a new facet of mathematical thinking. A traditional mathematics curriculum prepares the student to use deductive reasoning in problem solving, with little stress on inductive methods of solution. The reason generally given for such neglect is that it is impossible to consider an “adequate number” of cases for an inductive solution. Such reasoning must be reevaluated when one considers the possibilities available to the computer user.
Abordagem Transformacional para Variação Musical
Authors:   UFRJ, Almada Carlos de Lemos
Published: January 2021

This article is associated with a broad research addressing musical variation, whose main objective is the systematization of the analysis through the elaboration of an original analytical model. A new version of this model proposes a formal approach based on principles of the transformational theory. The present article is focused in the notion of variation isolated from a contextual framework (that is, out of temporal perspectives), setting the basis for further explorations. .Some original concepts, like derivative work, derivative space, attributes, among others, provide means for measurement of similarity relations between referential and derived musical ideas, as well as graphic representation for these relationships.
Dynamics of settlement and population of Anabar district: spatial analysis using GIS technologies
Authors: Filippova Viktoriia Viktorovna
Published: January 2021

The subject of the study is the location and population of the Anabar ulus in dynamics. The purpose of the study is to study the dynamics of the number and settlement of the population of the area under consideration using GIS technologies. The author conducted a study based on archival, statistical and cartographic sources. Verification of the reconstruction of the settlement network was carried out during field research in Anabarsky ulus in September 2020. The results of the work are presented by thematic layers in the GIS developed by the author, reflecting the dynamics of settlement from 1926 to 2020. The attribute tables contain data on the population, information about the location of settlements. В  The novelty of the study consists in the reconstruction of the settlement of the population of the Anabar district from 1926-2020 on the basis of multi-time maps and census data. It is established that as a result of the policy of transferring the nomadic population to a sedentary lifestyle and the enlargement of farms carried out during the Soviet period, there was a decrease in the number of settlements, while an increase in the population of settlements is traced. The compiled maps demonstrate a decrease in the area of population settlement in the territory of the studied area. A number of research sources are being introduced into scientific circulation for the first time and are used in the analysis of the settlement and population of the studied area.
The Use of Schema Theory, Information-Processing Theory, and Sociocultural Theory in Teaching Culturally Unfamiliar Texts in Second/Foreign Language Classrooms
Authors: Karami Amirreza
Published: January 2021

This theoretical review is an overview of three important theories: schema theory, information-processing theory, and sociocultural theory. Second/foreign language teachers need to familiarize themselves with these theories if they want to teach culturally unfamiliar texts more successfully
in their language classrooms. Although each of these theories can be applied to different stages of reading instruction (pre-reading, while-reading, and post-reading), schema theory is more applicable to the pre-reading stage; sociocultural theory to the post-reading activities; and information-processing
theory to the while-reading stage if teachers choose to use text-relevant video segments. A new framework for reading instruction, as well as some implications and suggestions for language teachers and researchers, are discussed in detail.
Effect of nitrogen rates on the growth and grain yield of a leaf early‐senescent rice mutant
Authors: Xu Yunji , Li Ke , Zhu Kuanyu , Tian Yinfang , Yu Qing , Zhang Weiyang , Wang Zhiqin
Published: January 2021

Nitrogen plays a vital role in regulating leaf senescence and yield formation in rice (Oryza sativa L.). However, little information is known about the effects of N rates on the growth and grain yield of rice plants with leaf early senescence. This study used a leaf early‐senescent rice mutant (osled) and its wild type (WT) (93‐11) and investigated how N rates of 0 kg ha–1 (0N), 240 kg ha–1 (240N), and 360 kg ha–1 (360N) influenced the main agronomic and physiological performance of the mutant osled. The results showed that 240N and 360N treatments increased grain yield of the osled plants by 201.5–222.9% and 266.4–287.9% as compared with 0N treatment, respectively, with the 360N treatment maintaining a similar agronomic nitrogen use efficiency (ANUE) as 240N. Leaf activity of the osled plants was enhanced with N supply levels showing increased leaf area, chlorophyll content, N content, and activities of N‐related enzymes and photosynthetic rate, and lowered malondialdehyde content. In contrast to 0N, the two N treatments significantly increased plant height, aboveground biomass, tiller number and percentage of productive tillers of both rice genotypes. Compared with 240N, the 360N treatment particularly increased grain weight and percentage of filled grains for the osled plants through improving leaf activity, root activity, and grain activity. These results verify that N treatment regulates leaf senescence and reduces yield loss of the osled plants, and simultaneously implied that the osled plants more positively respond to high N supply.
Diallel analysis for resistance to northern leaf blight in popcorn under contrasting nitrogen availability
Authors: Kurosawa Railan do Nascimento Ferreira , Amaral Junior Antônio Teixeira do , Vivas Marcelo , de Almeida Rafael Nunes , Vivas Janieli Maganha Silva , de Lima Valter Jário , da Silveira Silvaldo Felipe
Published: January 2021

Nitrogen‐use efficient and leaf‐disease resistant corn (Zea mays L.) cultivars are important to reduce costs and increase sustainability in farming. Studies have shown that non‐additive genes may enhance nutrient‐use efficiency and disease resistance in corn crops. This work aimed to analyze the responses of popcorn hybrids to northern leaf blight (NLB) under contrasting nitrogen availability. We evaluated NLB incidence and severity in 28 diallel hybrids and their parental lines. Competition trials were set in a randomized block design and arranged in a 6 × 6 lattice. The trials were conducted in four environments: two sites and two nitrogen availability conditions per site (ideal [IN] and low [LN]). The area under the progress curve of NLB incidence and severity was estimated for each genotype. To reduce the disease in multiple environments, general combining ability (GCA) of parentals is more important than specific combining ability (SCA) of hybrid combinations. The interactions between SCA and environment were significant for the disease resistance. Therefore, the best combinations should be identified for each environment so that NLB resistance could be enhanced. Low nitrogen availability enhanced the ability of parents to reduce NLB incidence and severity. Hybrid development is an efficient strategy to attain genetic gains in NLB resistance in multiple environments, regardless of N availability. The exploitation of additive gene effects may assist plant breeders in obtaining promising parents for the development of resistant hybrids in multiple locations.
Optimal planning of artificial lift operations in a shale gas multiwell pad
Authors: Achkar Victoria G. , Cafaro Vanina G. , Méndez Carlos A. , Cafaro Diego C.
Published: January 2021

Lifting operations play a key role to sustain shale gas wells productivity. Artificial Lift Systems (ALS) involve a wide range of techniques aimed at deliquifying wells. Although these operations are relatively mature for vertical wells in conventional reservoirs, enhancing productivity from shale gas wells has become a new frontier for unconventional production. The main contribution of this work is the development of the first Mixed Integer Linear Programming (MILP) formulation determining the integrated planning of several ALS in a multiwell pad. The model simultaneously manages ALS selection, investment and operational decisions, hedging against rapid decline curves in different wells. We introduce very detailed piecewise functions accounting for the ALS installation and removal times. The performance of the MILP is evaluated by solving five illustrative case studies.
Impact of defects on the decomposition of chemical warfare agent simulants in Zr‐based metal organic frameworks
Authors: Vo Minh Nguyen , Ruffley Jonathan P. , Johnson J. Karl
Published: January 2021

Metal organic frameworks (MOFs) containing zirconium secondary building units (SBUs) in UiO‐67 and related MOFs, are highly active for neutralizing both the chemical warfare agents and simulants, such as dimethyl methylphosphonate (DMMP). However, two recent publications gave conflicting reports of DMMP reaction with UiO‐67 under ultra high vacuum (UHV) conditions, with one reporting chemisorption and reaction (Wang et al., J Phys Chem C, 2017, 121, 11261–11272) and the other reporting only physisorption and reversible desorption (Ruffley et al., J Phys Chem C, 2019, 123, 19748–19758) from very similar temperature programmed desorption experiments. We show that the discrepancy between these experiments may be explained by different levels of missing linker defects in the UiO‐67 samples. We present density functional theory calculations showing that SBU sites having two‐adjacent missing linkers exhibit reaction barriers that are about 30 kJ/mol lower than SBU sites having a single missing linker. We also show that topology of the undercoordinated sites plays an important role in the reaction barrier under UHV conditions.
A validated model for prediction of survival to 6 months in patients with trisomy 13 and 18
Authors: Kosiv Katherine A. , Long Jin , Lee Henry C. , Collins R. Thomas
Published: January 2021

Congenital heart disease is exceedingly prevalent in trisomy 13 and 18. Improved survival following congenital heart surgery has been reported, however, mortality remains significantly elevated. Utilizing inpatient data on trisomy 13 and 18 from the 2003–2016 Pediatric Health Information System database, a survival model was developed and validated using data from the California Perinatal Quality Care Collaborative and the California Office of Statewide Health Planning and Development. The study cohort included 1,761 infants with trisomy 13 and 18. Two models predicting survival to 6 months of age were developed and tested. The initial model performed excellently, with a c‐statistic of 0.87 and a c‐statistic of 0.76 in the validation cohort. After excluding procedures performed on the day of death, the revised model's c‐statistic was 0.76. Certain variables, including cardiac surgery, gastrostomy, parenteral nutrition, and mechanical ventilation, are predictive of survival to 6 months of age. This study presents a model, which potentially can inform decision‐making regarding congenital heart surgery.
SRD5A3‐CDG:3Dstructure modeling, clinical spectrum, andcomputer‐baseddysmorphic facial recognition
Authors: Ben Ayed Ikhlas , Ouarda Wael , Frikha Fakher , Kammoun Fatma , Souissi Amal , Ben Said Mariem , Bouzid Amal , Elloumi Ines , Hamdani Tarak M. , Gharbi Nourhene , Baklouti Nesrine , Guirat Manel , Mejdoub Fatma , Kharrat Najla , Boujelbene Imene , Abdelhedi Fatma , Belguith Neila , Keskes Leila , Gibriel Abdullah Ahmed , Kamoun Hassen , Triki Chahnez , Alimi Adel M. , Masmoudi Saber
Published: January 2021

Pathogenic variants in Steroid 5 alpha reductase type 3 (SRD5A3)cause rare inherited congenital disorder of glycosylation known as SRD5A3‐CDG (MIM#612379). To date, 43 affected individuals have been reported. Despite the development of various dysmorphic features in significant number of patients, facial recognition entity has not yet been established for SRD5A3‐CDG. Herein, we reported a novelSRD5A3missense pathogenic variant c.460 T > C p.(Ser154Pro). The 3D structural modeling of the SRD5A3 protein revealed additional transmembrane α‐helices and predicted that the p.(Ser154Pro) variant is located in a potential active site and is capable of reducing its catalytic efficiency. Based on phenotypes of our patients and all published SRD5A3‐CDG cases, we identified the most common clinical features as well as some recurrent dysmorphic features such as arched eyebrows, wide eyes, shallow nasal bridge, short nose, and large mouth. Based on facial digital 2D images, we successfully designed and validated a SRD5A3‐CDG computer based dysmorphic facial analysis, which achieved 92.5% accuracy. The current work integrates genotypic, 3D structural modeling and phenotypic characteristics of CDG‐SRD5A3 cases with the successful development of computer tool for accurate facial recognition of CDG‐SRD5A3 complex cases to assist in the diagnosis of this particular disorder globally.
Creation and filtering of a recurrent spectral library of CHO cell metabolites and media components
Authors: Telu Kelly H. , Marupaka Ramesh , Andriamaharavo Nirina R. , Simón‐Manso Yamil , Liang Yuxue , Mirokhin Yuri A. , Bukhari Tallat H. , Preston Renae J. , Kashi Lila , Kelman Zvi , Stein Stephen E.
Published: January 2021

This paper reports the first implementation of a new type of mass spectral library for the analysis of Chinese hamster ovary (CHO) cell metabolites that allows users to quickly identify most compounds in any complex metabolite sample. We also describe an annotation methodology developed to filter out artifacts and low‐quality spectra from recurrent unidentified spectra of metabolites. CHO cells are commonly used to produce biological therapeutics. Metabolic profiles of CHO cells and media can be used to monitor process variability and look for markers that discriminate between batches of product. We have created a comprehensive library of both identified and unidentified metabolites derived from CHO cells that can be used in conjunction with tandem mass spectrometry to identify metabolites. In addition, we present a workflow that can be used for assigning confidence to a NIST MS/MS Library search match based on prior probability of general utility. The goal of our work is to annotate and identify (when possible), all liquid chromatography‐mass spectrometry generated metabolite ions as well as create automatable library building and identification pipelines for use by others in the field.
The hoarder, the oniomaniac and the fashionista in me: A life histories perspective on self‐concept and consumption practices
Authors: Alevizou Panayiota , Henninger Claudia E. , Stokoe Jennifer , Cheng Ranis
Published: January 2021

Increased negative media attention has focused on the environmental impacts the fashion industry has on the natural environment, thereby calling for solutions, focused on clothing purchase, use and end‐of‐life treatment. This research explores the relationship between consumers and their clothing consumption (from purchase through to disposal), through the lens of life histories, and thus exploring what impacts on end‐of‐life clothes treatment. The novelty of this study lies within connecting fashion consumption practices with the self‐concept in the context of clothing consumption (pre‐ purchase through to disposal), from an individual's life history perspective. This qualitative enquiry utilised life histories, thereby conducting 20 in‐depth semi‐structured interviews that were analysed through a grounded approach. Findings indicate that fashion consumption is heavily influenced by an individual's “self”, in that those that have a positive perception of themselves have reduced shopping habits, whilst those with a negative perception increase them. Our results show that our participants go through various consumption practices (hoarder, oniomaniac, and “fashionista”) that co‐exist within them and are influenced by the individual's self. Our study calls for more intergenerational research exploring fashion consumption and disposal.
Non‐deceptive counterfeit purchase behavior of luxury fashion products
Authors: Singh Devinder Pal , Kastanakis Minas N. , Paul Justin , Felix Reto
Published: January 2021

The luxury fashion industry suffers substantial losses due to non‐deceptive counterfeit purchase behavior. This study extends prior research on such behavior by investigating the factors influencing non‐deceptive counterfeit purchase behavior of luxury fashion goods in India, a country that scores high on collectivism and low on indulgence in regard to Hofestede's cultural dimensions. Specifically, (a) based on the extant literature as well as by (b) adding a novel variable, we theorize and empirically test a model that proposes a more comprehensive attitudinal construct specifically reflective of attitude to counterfeits by incorporating integrity, materialism, risk seeking, price–quality interface, smart shopper self‐perception, and subjective norms as antecedents of attitude towards counterfeit luxury products. Importantly, the paper investigates the mediating role of this comprehensive attitudinal construct in the relationship between intentions to purchase counterfeit and antecedents. The results offer novel theoretical insights that could be also advantageously employed by practitioners to restrain non‐deceptive counterfeit behavior.
Making sense of K‐12 competency‐based education: A systematic literature review of implementation and outcomes research from 2000 to 2019
Authors: Evans Carla M. , Landl Erika , Thompson Jeri
Published: January 2021

Background

Competency‐based education (CBE) is a systems‐change approach intended to re‐shape traditional understandings of what, when, where, and how students learn and demonstrate academic knowledge and skills. Research on the factors that affect K‐12 CBE implementation and the efficacy of different approaches has not yet been meticulously reviewed.

Aims

The purpose of this literature review was to examine the research on K‐12 CBE for factors that affect implementation, student outcomes, and the relationship between implementation and student outcomes.

Methods

A systematic literature review was conducted that included 25 peer‐reviewed studies and unpublished reports from 2000 to 2019 related to K‐12 students.

Results

Facilitators and barriers that affect K‐12 CBE implementation were fairly consistent across studies. Factors perceived as barriers in some contexts were viewed as facilitators in others—it all depended on stage of implementation. Findings about the outcomes of CBE for K‐12 students reflected mixed results with respect to claims that CBE implementation supports (a) academic achievement and progress; (b) intrinsic motivation and engagement; and (c) other important academic outcomes.

Discussion

Undergirding all findings in this review is the difficulty of isolating the research on implementation and outcomes of K‐12 CBE approaches in some “pure form.” It may make more sense for the field to coalesce around a common continuum of practices in relation to the key elements of CBE from more traditional models to more competency‐based models. Also, assessment as a key feature of CB implementation was absent from most of the studies reviewed which is notable given that determining competence is fundamentally an assessment decision. Directions for future research are discussed.

Conclusion

For many, the promise of CBE and related practices is that student achievement will improve and minimize equity gaps. This systematic review serves to amplify what is known about CBE approaches and what still needs investigation.
Genetic diversity among Brazilian carioca common bean cultivars for nitrogen use efficiency
Authors: Zeffa Douglas Mariani , Moda‐Cirino Vânia , Delfini Jéssica , Medeiros Isabella Arruda , Koltun Alessandra , Nogueira Alison Fernando , Scapim Carlos Alberto , Gepts Paul , Gonçalves Leandro Simões Azeredo
Published: January 2021

The objective of this study was to determine the genetic diversity among Brazilian carioca common bean (Phaseolus vulgaris L.) cultivars for traits related to nitrogen use efficiency (NUsE). An additional objective was to identify potential parents and promising parental combinations to assist common bean breeding programs in the development of cultivars with improved NUsE. The experiments were carried out at the Experimental Stations of the Instituto de Desenvolvimento Rural do Paraná (IDR–Paraná) in Londrina and Ponta Grossa, Brazil, during the rainy season in 2017. Thirty‐nine common bean cultivars were evaluated under high (40 kg N ha−1) and low N (0 kg N ha−1) applied as top‐dressing. The cultivars were genotyped using the genotyping‐by‐sequencing (GBS) approach with restriction enzyme CviAII. A total of 23,823 single nucleotide polymorphism (SNP) markers were identified throughout the common bean genome. A wide genetic variability was observed for NUsE‐related traits under high and low N conditions. In addition, correlations were found between shoot dry biomass and NUsE, N uptake efficiency (NUpE), and N utilization efficiency (NUtE) under low N, indicating the possibility of indirect selection of these traits by the plant shoot dry biomass. Interestingly, the most low‐N‐tolerant cultivars were not necessarily the most responsive and/or NUsE, suggesting that different morphophysiological mechanisms control these traits. The cultivars that stood out positively in this study can be used as parents in breeding programs aimed at developing cultivars that are adapted to N limitation.
The stakeholder engagement in the European banks: Regulation versus governance. What changes after the NF directive?
Authors: Cosma Simona , Leopizzi Rossella , Pizzi Simone , Turco Mario
Published: January 2021

Previous studies show regulation and corporate governance play an important role in affecting CSR processes and outcomes. The stakeholder engagement (SE) process represents a good practice of Corporate Social Responsibility (CSR) and, at the same time, an aspect of substance over form, within the CSR policies. In spite of its relevance, SE represents a little explored field of research. The purpose of this paper is to investigate if the improvements in SE processes are actually driven by regulation rather than by some elements of corporate governance. The study examines the effect of the regulation and some board's characteristics on SE. Specifically, in 2017 the introduction of EU non‐financial information Directive (Directive 2014/95/EU) shifts the disclosure of non‐financial information from the voluntary to the mandatory realm: in this mandatory context, the quality of the SE process that is indirectly disclosed in non‐financial information, could improve. By using a content and statistical analysis, through performing 4 two‐way Analysis of Variance, the study reveals that the effects of the introduction of the Directive 2014/95/EU on the stakeholder engagement process have been limited and the improvements in SE before and after the introduction of the Directive link to the Board of Directors characteristics. These findings are interesting for academics, by enriching the academic debate on mandatory versus voluntary disclosure and the relationship between board attributes and sustainability, for policy makers, by providing suggestions to favour organisational change of the firms, and for managers, by identifying the desirable characteristics of the Board of Directors.
State‐of‐the‐Art: Applications and Industrialization of Lignin Micro/Nano Particles
Authors: Chen Kai , Wang Shiyu , Qi Yungeng , Guo Hong , Guo Yanzhu , Li Haiming
Published: January 2021

As a new product of high‐value utilization of lignin, lignin micro/nano particles (LMNPs) have attracted the attention of researchers due to their non‐toxicity, corrosion‐resistance, UV resistance, and other excellent characteristics and potential application value. This article outlined the main preparation methods of LMNPs at the current stage, summarized and compared them from three perspectives of preparation technology, final product state and product composition. Subsequently, based on the different focuses of the properties of LMNPs, their application research progress as fillers, UV blockers, drug delivery carriers, among others, were introduced. Then a concise analysis of the technical and economic assessment and life cycle assessment of LMNPs in the process of industrialization was made. Finally, the main problems at present and the future development directions were analyzed and prospected to provide references for the deep processing of forest resources and the development of bio‐based nanomaterials.
Pattern synthesis of timed antenna array with the exploitation and suppression of harmonic radiation
Authors: Chakraborty Avishek , Ram Gopi , Mandal Durbadal
Published: January 2021

The pattern synthesis of timed antenna array with the exploitation and suppression of harmonic radiation is proposed in this paper. Timed arrays are the time‐domain alternatives of conventional antenna arrays, where an additional control parameter “time” is used to generate the desired time‐averaged radiation pattern. This additional control also comes with the inherent hindrance of harmonic radiation, generally considered as an undesired effect of time modulation. In this work, this hindrance is overcome with different objectives considering the exploitation and suppression of harmonic radiation of timed arrays. To demonstrate the exploitation of harmonic radiation, a simultaneous sum and difference pattern with reduced sidelobe suitable for monopulse tracking radar systems is obtained at the fundamental and the first harmonic frequency by an optimal subarrayed pulse splitting and shifting approach. Two separate cases, considering uniform and optimized static excitations along with the proposed subarrayed pulse sequence, are presented for the exhaustive analysis of the simultaneous multibeam pattern. To address the suppression of harmonic radiation, the sidelobe level (SLL) at the fundamental frequency and the sideband levels (SBLs) of higher‐order harmonic frequencies are simultaneously reduced. In this regard, a unique pulse shifting approach for the edge elements of the array, along with an optimal set of static excitations, is proposed to enhance the efficiency of the antenna system by reducing SLL and SBLs at the same time. Two uniquely defined cost functions are chosen to address the above‐mentioned objectives by exploiting and suppressing the harmonic radiation of timed arrays, which further increases the adaptability and reconfigurability of the array. A set of 16‐element “time‐modulated” linear array (TMLA) is considered for optimization, and a wavelet mutation‐based differential evolution (DEWM) algorithm is employed to obtain the optimal solutions. Obtained numerical results are reported and also compared with previously published works to show the proposed approach's potentialities.